Our objective was to analyse the cost effectiveness of computed tomography (CT) screening for lung cancer in terms of the cost per long-term survivor, which has not been evaluated to date.Estimations were computed based on data from the Surveillance, Epidemiology, and End Results registries covering years 1999–2003. The design framework of our model allowed for the incorporation of multiple values taken from the epidemiological and clinical literature to be utilised for cost inputs, scope of patients screened, diagnostic staging, and survival percentages applied separately to two cohorts: age 40–79 and 60–79 years. This enabled the analysis of over 1400 scenarios, each containing a unique set of input values, for which the estimated cost per 5-year survivor (CP5YS) was compared between the symptom-detected and proactive screening approaches.Estimated CP5YS were higher for the symptom-detected approach in all 729 scenarios analysed for the cohort ages 60–79 years, ranging from approximately $5800 to $116 700 increased cost per 5-year survivor (CP5YS). For the cohort ages 40–79 years, 75% of the 729 scenarios analysed showed increased CP5YS for the symptom-detected approach ranging from $5700 to $110 000 increased CP5YS. Total costs and total 5-year survivors were higher for the proactive screening method for all scenarios analysed across both cohorts with increases ranging from 50–256% and 98–309%, respectively.The predicted increase in long-term survival with CT screening and the potential for better utilisation of health-care dollars in terms of CP5YS, particularly when screening patients over the age of 60 years, are critically important considerations in directing effective future lung cancer management strategy. Lung cancer is the leading cause of cancer deaths nationwide. An estimated 162 000 people would have died of lung cancer in the United States in 2006 . CurrentBecause lung cancer is seldom symptomatic in early stage and treatment in advanced stage has very low survival , currentResults from the International Early Lung Cancer Action Project (I-ELCAP) demonstrating striking improvement in early stage detection of lung cancer by low-radiation-dose computed tomography (CT) screening . KnudsenMany investigations of cancer treatment cost-effectiveness utilise quality-adjusted life year (QALY) as the primary metric to measure the results of interventions that provide some improvement in quality and/or duration of life, but only for limited periods of time. For example, a cancer treatment that results in improvement in duration of survival by 3 months at cost of $25 000 would result in a cost per year or QALY of approximately $100 000, as it requires four patients, each experiencing a 3-month improvement in survival to add up to a year of life gained. Although this metric has the advantage of wide utilisation, in a certain sense, it is a misleading figure, as in this example no single patient would actually survive 1 year. Preventive screening measures, where the positive impact on health outcomes may not be measurable for many years, may be difficult to quantify using QALYs . ArguablWe constructed a mathematical model based on multivariate analysis of empirical data to estimate the ratio of screening, diagnosis, and treatment costs per 5-year non-small-cell lung cancer (NSCLC) survivor for two different lung cancer management strategies, STID and EDCTS. These estimations were computed in 2005 USD based on the most recent 5 years of data available, extending from 1999 to 2003, within the 13 Surveillance, Epidemiology, and End Results (SEER) data registries . With reThe design framework of our model allowed for the incorporation of multiple values taken from the epidemiological and clinical literature to be utilised for cost inputs, scope of patients screened, diagnostic staging, and survival percentages. This methodology enabled the analysis of over 700 scenarios for each of the two cohorts , each containing a unique set of input values. For each of these scenarios, the estimated CP5YS was compared between the STID and EDCTS approaches. By analysing a broad range of parameter values, we were able to evaluate the sensitivity of selected variables by using a range of favourable and unfavourable estimates. In addition, this study design also enabled the evaluation of completely separate parameter estimates and calculations from different sources of published data. Our model assumes that the capital equipment and resources necessary for both management strategies are already in place.Population screened. The initial I-ELCAP screening study published in 1999 screened at-risk persons aged 60 years or older  . To evalWe then estimated the percent of this population that would be unfit for surgery by using SEER data to determine the percent of stage I tumours diagnosed in patients aged 40–79 and 60–79, respectively for each cohort, in whom surgery was not recommended or was contraindicated . This resulted in an estimate of 14.7% for the cohort ages 40–79 years who are excluded from screening because they would not be fit for surgery and 17.0% for the cohort ages 60–79 years. It is important to emphasise that some individuals who would not be the candidates for standard surgical procedures might still receive potentially curative treatment with minimally invasive surgical approaches, radiation therapy, radiofrequency ablation, or other methods.Using steps (1), (2), and (3) described above, we quantified an estimate of the total population that would be eligible for screening in each cohort in accordance with I-ELCAP inclusion criteria, with an upper and lower bound estimate for the percent of the population with a 10 pack-year history of smoking . StatistThe choice of different inclusion criteria  would result in changes in number of individuals screened, costs, and results.vs annual repeat screens  following up with an annual repeat screen  than in annual repeat screening. In addition, the percent of cases where malignancy was found was also different for baseline screens t screen .The procedures carried out as part of the baseline and annual repeat screens were based on I-ELCAP protocol, revision dated 20 October 2006 . The I-EFor the cohort ages 60–79 years, the number of malignant tumours identified by screening in the baseline and annual repeat screens was derived by multiplying the percent of malignant tumours identified in the I-ELCAP studies published in 1999 and 2001 that screened patients aged 60 years and over . For theFor the EDCTS approach, our model incorporated three different screening procedure cost estimates for multidetector CT (MDCT) scans and fine-needle aspiration biopsies (FNAB), and two cost estimates for positron emission tomography (PET) scans taken from the clinical literature . The first set of estimates for CT and FNAB were based on the actual costs incurred by I-ELCAP volunteers, as recorded by the New York-Presbyterian Hospital's financial system cost database . The firTumour quantity and distribution by stage for the STID method was based on SEER data from 1999 to 2003, using lung and bronchus NSCLC that were invasive, microscopically confirmed, and the patient's first primary cancer. SEER tumours of unknown stage were allocated to stages based on the distribution percentages of the staged SEER tumours.The quantity of tumours for the EDCTS method was comprised of two components: (1) screen-detected malignant tumours (quantification described above); and (2) non-screen-detected tumours (‘symptomatic tumours’). For the first year of screening implementation it was assumed that the number of symptomatic tumours would include all SEER reported tumours for that year. For subsequent years, symptomatic tumours were calculated by multiplying the percent of the population that did not comply with screening recommendations (based on estimates described for ‘Population Screened’ above) to the SEER tumour population. For example, if the SEER data identified 1000 tumours in a given year, and an estimated 60% of the population did not comply with screening recommendations, then it was assumed that 600 (=1000 × 60%) symptomatic tumours would be recorded in that year in addition to screen-detected tumours. Components (1) and (2) were added together to determine the total EDCTS tumours identified each year.The stage of EDCTS tumours was determined as follows: (1) Symptomatic tumours, as described above, maintain the SEER stage distribution, with the same treatment for tumours of unknown stage as described above for the STID method. (2) Three estimations were used to determine the number of remaining screen-detected malignant tumours allocated to each stage. The first estimation was based on I-ELCAP data .For this parameter, we included separate estimates and calculations from different sources of published data on the cost of diagnosis and treatment for lung cancer by stage. These sources included data based on Medicare payments for lung cancer patients in nine SEER registries .For the EDCTS approach, total costs were comprised of screening cost and the cost of treatment by stage. However, calculations for the cost of treatment by stage included diagnosis and staging procedures that are also covered in the screening protocol. To avoid double-counting these expenditures, the screening costs for patients diagnosed with malignant lung cancer were removed from the total costs, as these costs are already included in the cost of treatment by stage. As such, the resulting total costs for the EDCTS approach includes the sum total of screening costs for patients not diagnosed with malignant cancer  and the cost of treatment by stage (including diagnostic costs) for the entire tumour population, including screen-detected and non-screen-detected tumours. Total costs for the STID approach were limited to the cost of treatment by stage with screening costs assumed to be zero.Survival rates were applied to the population of tumours by stage to determine the estimated number of associated 5-year survivors. The same survival rates were used for both the STID and EDCTS calculations. Three different sets of survival rate estimates were included in our analysis. The first set of estimates was based on published data on over 5300 lung cancer cases compiled from The University of Texas MD Anderson Cancer Center and the classification research database from the Reference Center for Anatomic and Pathologic Classification of Lung Cancer  . For the6) total scenarios for each cohort analysed . The CP5YS ratio was determined by first calculating the estimated number of NSCLC tumours distributed by stage for the 5-year period for both the STID and EDCTS approaches. The cost of diagnosis and treatment by stage were applied to these tumour populations, with screening cost also added to the EDCTS costs. The estimated percent of 5-year survivors for each stage was also applied to the tumour populations. The ratio of total CP5YS was then calculated see .Note that the total survivors and total cost figures reported in this analysis refer only to the subset of the US population studied and are not extrapolated to represent nationwide estimates.Across all 729 scenarios analysed for the cohort ages 40–79 years, the total CP5YS ranged from $157 300 to $293 800 for the STID method, and from $105 100 to $288 100 for the EDCTS method. The costs per 5-year survivor were higher for the STID approach in 75% of the scenarios analysed, ranging from approximately $5700 to $110 000 increased CP5YS under the STID method for those scenarios  See the.The EDCTS method resulted in a 27–66% increase in the number of tumours identified when compared with the STID method .Scenario code BDHJOQ was associated with the lowest CP5YS of approximately $105 100 per 5-year survivor for the EDCTS method and $157 300 for the STID method. Scenario code CEIKNP was associated with the highest CP5YS of approximately $288 100 per 5-year survivor for the EDCTS method and $293 800 for the STID method.The scenario most favourable towards the EDCTS method in terms of the comparative decrease in costs per 5-year survivor was scenario code BDHJNR, in which the EDCTS CP5YS was approximately $110 000 less than the STID ratio for that same scenario (305% more EDCTS 5-year survivors in that scenario). The scenario least favourable towards the EDCTS method in terms of the comparative increase in costs per 5-year survivor was scenario code BDIKOR, in which the EDCTS CP5YS was approximately $53 400 more than the STID ratio for that same scenario (248% more EDCTS 5-year survivors in that scenario).Across all 729 scenarios analysed for the cohort ages 60–79 years, the total CP5YS ranged from $149 400 to $282 100 for the STID method, and from $86 400 to $233 300 for the EDCTS method. The costs per 5-year survivor were higher for the STID approach in all scenarios analysed, ranging from approximately $5800 to $116 700 increased CP5YS under the STID method for those scenarios  See the.The EDCTS method resulted in a 24–60% increase in the number of tumours identified when compared with the STID method .Scenario code BDHJOQ was associated with the lowest CP5YS of approximately $86 400 per 5-year survivor for the EDCTS method and $149 400 for the STID method. Scenario code CEIJNP was associated with the highest CP5YS of approximately $233 300 per 5-year survivor for the EDCTS method and $282 000 for the STID method.The scenario most favourable towards the EDCTS method in terms of the comparative decrease in costs per 5-year survivor was scenario code BDHJNR, in which the EDCTS CP5YS was approximately $116 700 less than the STID ratio for that same scenario (269% more EDCTS 5-year survivors in that scenario). The scenario least favourable towards the EDCTS method in terms of the comparative decrease in costs per 5-year survivor was scenario code CEIKOQ, in which the EDCTS CP5YS was approximately $5800 less than the STID ratio for that same scenario (98% more EDCTS 5-year survivors in that scenario).The advisability of population screening for lung cancer is currently a topic of active debate. Because of the potential high cost of lung cancer screening programmes, cost-effectiveness questions are an important component to be evaluated. This article attempts to inform the debate by a multivariable analysis model. We incorporated a range of optimistic and pessimistic input variables taken from literature sources on both sides of this debate. In addition, this analysis presents an important method for evaluating a lung cancer-screening programme in contrast to analyses using QALYs, which can be misleading in terms of the efficacy of treatment regimens, particularly when there is little chance of long-term survival, as in the treatment of stage IIIB and IV NSCLC with chemotherapy. Owing to the frequent use of the QALY metric in the literature, we have provided for the reader a cost-per-year of life calculation for all 729 scenarios in the Appendix Table A3 and Table A4 to allow a rough comparison to other studies evaluating cost-effectiveness on a per-year basis. It should be emphasised, however, that the data in Table A3 and Table A4 is calculated assuming that these lung cancer survivors live only 5 years. It is therefore a conservative estimate and overstates the cost-per-year of life, as many lung cancer survivors detected by screening will live longer than 5 years  ‘sis bias , no empiAnother form of overdiagnosis could exist in instances where comorbid disease would kill the patient before symptoms of lung cancer were experienced. This form of overdiagnosis bias can be reasonably assumed to be rendered largely irrelevant in medical environments, where patients are managed with good, sensible clinical judgment by physicians adept in identifying comorbid disease and reasonably accurately estimating the anticipated survival of their patients. Furthermore, in this study we have carefully taken into account the percentage of patients eligible for screening who have serious comorbid disease and excluded them from our analysis . We have been conservative in this approach by additionally excluding patients aged 80 years and above from screening, although many 80-year-olds are perfectly capable of undergoing minimally invasive surgical resection of lung cancers or being treated with radiationtherapy.Finally, overdiagnosis could result if spontaneous remission of a preclinical cancer were to occur. Case reports of this phenomenon are extremely rare  ‘ tumours . CancersLead-time bias’: screening-detected patients are accorded extended survival times solely because cancer was detected earlier owing to screening, although death occurred at the same time as would have happened without screening ((3) ‘creening  are baseAlthough some emphasise that the risks and complications of lung cancer screening may be considerable  are substantially higher than direct costs . As survOur analytical model offers an innovative tool that provides data estimates that contribute insights into the continuing debate on the wisdom and advisability of implementing state and/or nationwide CT screening programmes. The predicted increase in long-term survival with CT screening and the potential for better utilisation of health-care dollars in terms of CP5YS, particularly when screening patients over the age of 60 years, are critically important considerations in directing effective future lung cancer management strategy.


Paroxysmal atrial fibrillation (PAF) is defined as recurrent AF terminating spontaneously within 7 days. This definition allows the consideration of any AF occurrence lasting < 7 days as paroxysmal, irrespective of the frequency and duration of episodes. The aim of this study was to investigate symptomatic AF burden (AFB) defined as total duration of symptomatic AF episodes within 3 months prior to abalation, for prediction of outcome after pulmonary vein isolation (PVI).A total of 320 consecutive patients with symptomatic AF  were enrolled. AFB in patients with PAF was defined as time spent in AF within 3 months prior to PVI. After the AFB cut-off point was optimized at 500 h, patients with PAF were categorized into 2 groups: Group 1 - patients with AFB< 500 h (n=192), Group 2 - patients with AFB≥ 500 h (n=52). Patients with persistent AF  comprised control group (Group 3). PVI was performed either with irrigated tip catheter (n=215) or using cryoballoon (n=105). The endpoint of study was first documented recurrence of AF >30 sec.Symptomatic AFB was found to be appropriate for prediction of outcome after PVI. The freedom from AF within 2 years was observed in 69%, 31%, and 43% patients in Group 1, 2 and 3, respectively .Low AFB < 500 h /3 months was associated with better outcome after PVI. Patients with PAF and high AFB should be treated as patients with PersAF.  Pulmonary vein isolation (PVI) has been shown to be effective for treatment of paroxysmal atrial fibrillation (PAF) -3. HowevA recently published Expert Consensus Statement has recognized the significance of symptomatic status at enrollment for outcome after PVI . The ass A total of 320 consecutive patients with symptomatic AF refractory to beta-blockers and to ≥ 1 antiarrhythmic drug including class I agents, sotalol, and amiodarone, were enrolled into the study. The baseline characteristics of patients are shown in  Three months prior to the procedure, patients with PAF were asked to keep a diary of their symptoms. AFB was calculated as total duration of AF episodes recorded in the diary as described in our previous study .  We decIn 108 patients, 422 PVs were isolated using a 3.5 mm irrigated tip-catheter . The cut-off temperature of generator was 42” C and energy delivery was limited to a maximum of 35 W. Successful ablation was defined as a complete disappearance of the fragmented signals during mapping with a decapolar Lasso catheter  at the PV antrum. If there were residual signals recorded after ablation, the site was paced to determine whether the far field signals were present. In other 107 patients treated with radiofrequency, mapping was performed using high density mapper (MESH. Bard inc. USA). We started an ipsilateral isolation of both sides. The complete loss of PV and antral atrial signals under the mapping electrodes was defined as complete antral PVI.In the remaining 105 patients, 420 PVs were isolated using a 23 mm or 28 mm cryo balloon. If necessary, the residual gap was closed using the large tip catheter FreezorMax™. Mapping was performed by either a suitable Lasso catheter or a 3-D mapping system (NavX™). The balloons were advanced into the antrum. The balloon was inflated and the degree of occlusion was tested by contrast injection under fluoroscopic control. Ablations at a single site were repeated with guide wire positions in different branches of the PV to obtain better tissue contact in different parts of the antrum. If complete isolation with one balloon size could not be achieved, another balloon size and/or a larger tip were used to complete the PVI. The baseline data of patients according to ablation technique are shown in the In 244 patients considered according to the definition of HRS/EHRA/ECAS as having PAF only PVI was performed.  In remaining 76 patients with persistent AF, irrespective of the energy used for PVI, additional linear lesions such as a roof line and the mitral isthmus line were also performed using a radiofrequency catheter.Left atrial short and long diameters ; LALD-apical measurement) were assessed in the apical four-chamber projection [12] .All patients were seen in our outpatient clinic 3 months after catheter ablation and every 3 months thereafter for 2 years and additionally in the case of symptomatic recurrence of AF. A 7-day Holter ECG was performed at each follow-up visit. After discharge, patients treated with antiarrhythmic drugs prior to ablation, received the same antiarrhythmic drug therapy during the first 3 months. If sinus rhythm was maintained, antiarrhythmic therapy was terminated three months after PVI. Beta-blockers were continued in patients with hypertension or coronary artery disease. The endpoint of the study was the first documented AF recurrence > 30 s. The first three months after ablation were considered as a blanking period.This study was designed as a validation cohort study. Our aim was to test whether the AFB calculated based on patients' symptoms and left atrial diameters may be used for prediction of outcome and if yes to define and validate cut-off values for both parameters that would allow discriminating between patients with high and low risk of AF recurrence after ablation. To solve this issue ROC curve analysis should be performed .In the case of absence of the gold standard or if independent data set is not available, the parameters of interests should be analyzed by randomization of study patients in two groups - one to derive the model and the other to validate it . We randOut of 122 patients with PAF randomized to training set 45 (36.9 %) reached endpoint. The test did not reveal an effect of the applied energy source on the outcome . The areAs in the training set the effect of the ablation energy could not be revealed . The are2=26.11, p< .001), and Group 3 (n=76) . Of note, no significant difference between Group 2 and Group 3 was found .Out of 320 enrolled patients, 182 (57 %) were free of documented AF recurrence during 2-year follow-up. Kaplan-Meier survival analysis has shown that dichotomized AF burden was strongly associated with outcome . The logIn univariate analysis, AFB ≥ 500 hours, LALD ≥ 60 mm, and the presence of coronary artery disease were associated with the recurrence of AF . In multThe detailed data on outcome according to the energy source used is given in the The subgroup analysis showed significant differences in outcome between Group 1 and other AF groups in patients with LALD< 60 mm. . In contIn 27 patients (8.4 %) left atrial tachycardia (LAT) was observed during follow-up. In 19 of them (70 %) LAT was transient and in 8 patients (30 %) additional ablation was needed.The main finding of this study is that symptomatic AF burden can be used for prediction of outcome patients with PAF. The quantitative evaluation of symptomatic AFB based on the patient diary prior to procedure allowed discrimination between patients in low or high risk groups and may be useful for the choice of the appropriate ablation strategy. We found that symptomatic AFB before ablation had significantly better outcome, whereas no difference was found between patients with PAF and AFB ≥ 500 hours within the last 3 months prior to PVI and patients with persistent AF. Poor outcome after PVI in patients with persistent AF and in up to 40% patients with PAF was observed in several previous studies -6. On thImportant is the fact that patients with low AFB have better outcome irrespective of the ablation strategy. For example, these patients may be considered for PVI with the cryoballoon. This ablation technique has been shown to be effective for the majority of patients with PAF and free from such severe complications as esophageal fistula and PV stenosis as well . ConsequThe association between the left atrial size and high recurrence rates after ablation was described in several previous studies -8,18. AlOur results suggest that patients with PAF and very high AFB must be considered as being in progression to persistent AF and accordingly treated. The patients with low AFB and non-dilated left atrium have a high probability to be in sinus rhythm after single PVI. The following limitations of the study should be acknowledged. We could not identify all episodes of AF, particularly asymptomatic, because no monitoring was performed before ablation. We instead relied on patient self-reports. Furthermore, we only assessed symptomatic burden during a limited period of 3 months before ablation. If an implantable loop-recorder was used, it would be possible to include potential asymptomatic AF burden into analysis. The last limitation we have to mention is  follow up time of 2 years.


From 2003 through 2005, the 2 agencies agreed to conduct an intervention program using Salud para su Corazón with promotores de salud  in high-risk Hispanic communities served by community health centers (CHCs) in the border region to reduce risk factors and improve health behaviors.In 2002, the National Heart, Lung, and Blood Institute partnered with the Health Resources and Services Administration's .Changes in heart-healthy behaviors were observed, as they have been in previous promotores de salud into clinical practices is a promising strategy for culturally competent and effective service delivery. Promotores de salud build coalitions and partnerships in the community. The Salud para su Corazón-HRSA initiative was successful in helping to develop an infrastructure to support a promotores de salud workforce in the US-Mexico border region.Results suggest that integrating  Since 1990, cardiovascular disease (CVD) has been the leading cause of death among the US Hispanic population . The ext's) Bureau of Primary Health Care and Office of Rural Health Policy to address cardiovascular health in the US-Mexico border region. The NHLBI-HRSA interagency relationship resulted in an agreement from 2003 through 2005 to conduct an intervention using the cardiovascular health promotion program Salud para su Corazón  with promotores de salud  in 4 high-risk Hispanic communities in the border region  partnered with the Health Resources and Services Administration's  to describe the lessons learned during implementation and evaluation of Salud para su Corazón in all 4 health care settings.The purpose of this article is 3-fold: 1) to describe the strategies used by the NHLBI-HRSA partnership with 4 HRSA-funded CHCs to implement cardiovascular health promotion and disease prevention activities in their respective communities; 2) to describe the effects of Salud para su Corazón program because of their location in the US-Mexico border region, the array of settings for primary health care and intervention that they presented, and the high CVD death rates of the communities they served  increase CVD knowledge and heart-healthy practices; 2) increase participation in physical activity; 3) decrease blood pressure, cholesterol levels, blood glucose levels, and body mass index (BMI); 4) increase awareness and knowledge through community-based health promotion activities; and 5) increase involvement and support for munities .promotores, medical providers, certified diabetes educators, medical support staff, administrators, and the board of directors. The training for Salud para su Corazón is integrated into the medical providers' referral system after the patient is referred to the promotores.GCHC uses several components within the center to integrate self-management interventions into the center's medical practice. Center components include patients, promotores model at GCHC can be summarized as follows: 1) community outreach by promotores facilitates patient appointments with the medical staff (physician visit) facilitates patient appointments with the medical staff (physician visit), and appointments are scheduled; 2) an assessment plan is developed by the medical staff; 3) medical staff initiate educational directives ; 4) a treatment plan is developed that includes laboratory assessment, medication, care plan, and referral to the promotores program; 5) the promotores program includes group classes  and individual support; and 6) follow-up is provided by both medical and promotores staff as needed.The clinical directives for implementing the Salud para su Corazón-HRSA initiative adopted several approaches to community participation and capacity building. It established collaboration among select staff from NHLBI and HRSA and researchers from the University of Texas School of Public Health, El Paso Regional Campus, to provide consultation, mentorship, and guidance to CHC staff, promotores, and other personnel involved with project activities at the community level. This team delivered Salud para su Corazón resources and materials to all 4 CHCs to support delivery of community education. For example, it conducted monthly calls for the duration of the project with key staff and lead promotores from each CHC to review progress and to provide an opportunity to discuss any aspect of the projects.The promotores training activities, following protocols similar to those previously implemented in other Salud para su Corazón programs  because of their similar timing of assessments and similar integration of clinical and community outreach activities that used t test to evaluate differences from baseline to 6 months  and from baseline to 12 months  for CSV and GCHC. Repeated-measures 1-way analyses of variance were used to evaluate matched sample comparisons between baseline and 2 follow-up points (3 and 6 months after the intervention) for NCHS.We used a 2-sample paired We found statistically significant decreases from baseline to 6 months after the intervention for 3 clinical outcomes: diastolic blood pressure, LDL cholesterol level, and HbA1c . Only LDWe also noted improvements in behavioral and clinical data from NCHS. Significant improvements in heart-healthy behaviors were observed for the 3 subscales of My Family Habits. Participants increased the frequency of reporting their consumption of healthy amounts of salt and sodium, cholesterol, and fat, and engaging in behaviors related to healthy eating for adequate weight. We also observed significant changes in waist circumference and weight. Waist size decreased from 37.4 inches at baseline to 36.1 inches at 3 months after the intervention and 36.14 inches at 6 months after the intervention. After 3 months of follow-up, study participants' weight had also decreased and was maintained after 6 months of follow-up. The proportion of study participants who reported engaging in physical activity after 3 months of follow-up showed a significant increase from baseline; the change observed at 3 months of follow-up was maintained after 6 months of follow-up.Salud para su Corazón-HRSA initiative achieved positive changes in heart-healthy behaviors and improved the CVD risk profile among most study participants. It also succeeded at capacity building and infrastructure development.The Salud para su Corazón studies, lending credibility to the efficacy of the promotores program in a clinical setting  open and frequent communication; 2) wide organizational acceptance of promotores; 3) regular staff meetings (in which promotores participate) to assess progress and identify issues; 4) extensive training of promotores; 5) thorough documentation; 6) management support; 7) provider involvement including training, recruitment, support, and participation; and 8) regular assessment of patient satisfaction and feedback. Finally, the GCHC has identified several benefits of its promotores program. The benefits to the provider include more efficient use of time, reinforcement of the treatment plan, assessment of social needs and concerns, extension of physician services, identification of health advocate and additional clinic and service referrals, and improved patient control of diabetes. Benefits to the patient include more time dedicated to education, increased awareness of the need to adhere to treatment plans, individualized care, improved access to care, specific needs met by appropriate referrals, and improved health outcomes.Several key components of success of this clinical Salud para su Corazón-HRSA initiative was not able to implement a more sophisticated study design. This limitation is faced by many community-based organizations, including CHCs, because of the great need to provide direct community outreach and clinical services to their clients. Additionally, CHCs did not collect sociodemographic and other pertinent information that may confound intervention effects because of resource limitations . As a result, less emphasis and priority were given to research and to adequate collection of data to support the CHCs' Salud para su Corazón-HRSA programs.The study has limitations related to research design and to methods of data collection and evaluation. The Challenges still exist in implementing standardized research protocols. Data collection tools were difficult to standardize. We were unable to consolidate the development of a complete database that could match each participant with all data points needed for all variables of interest . As a consequence of this limitation, the evaluation is constrained by the difficulty in conducting analyses of confounding factors. Therefore, these results should be interpreted with caution. Expertise in evaluation and statistical analyses needs to be an intricate part of the infrastructure being developed for CHCs as community outreach activities are integrated with clinical encounters. The implementation of electronic records appears to be a promising strategy.promotores are working in conjunction with the medical system to combat heart disease and address CVD risk factors among Hispanic populations living in the US-Mexico border region  and infusing a well-developed, science-based approach is a major challenge in these types of health promotion and disease prevention initiatives. Community-based participatory research is a promising approach that needs to be strengthened with CHCs when r region .Salud para su Corazón-HRSA initiative to enhance the capacity of CHCs and their providers to ensure that the promotores model can be sustained in their community settings.We offer recommendations based on the experience of the Include support groups. Complement the Salud para su Corazón training with informal support groups. The benefits of support groups are to help participants maintain healthy behaviors and to facilitate follow-up with participants.Provide a clinical measures graph. Use the clinical measures to help motivate participants. Provide a graph of the key measures to give participants a visual image of their progress.Develop a referral, follow-up, and documentation system. Produce an effective system that is consistent with self-management clinical practice. Include referral, follow-up, feedback, and documentation practices to standardize and track participant and program information.Extend the evaluation timeline. Measures taken at baseline and 6 and 12 months after the intervention are crucial to documenting a program's success. Projects should be given at least 1 year to evaluate their outcomes.Provide evaluation training. Evaluation training is needed for program coordinators and promotores. Without critical evaluation skills, the programs are unable to adequately assess their respective programs and provide justification for additional funding.


Air Pollution has been associated with significant adverse health effects leading to increased morbidity and mortality. Cumulative epidemiological and experimental data have shown that exposure to air pollutants lead to increased cardiovascular ischemic events and enhanced atherosclerosis. It appears that these associations are much stronger with the air particulate matter (PM) component and that in urban areas, the smaller particles could be more pathogenic, as a result of their greater propensity to induce systemic prooxidant and proinflammatory effects. Much is still unknown about the toxicology of ambient particulates as well as the pathogenic mechanisms responsible for the induction of adverse cardiovascular health effects. It is expected that better understanding of these effects will have large implications and may lead to the formulation and implementation of new regulatory policies. Indeed, we have found that ultrafine particles (<0.18 μm) enhance early atherosclerosis, partly due to their high content in redox cycling chemicals and their ability to synergize with known proatherogenic mediators in the promotion of tissue oxidative stress. These changes take place in parallel with increased evidence of phase 2 enzymes expression, via the electrophile-sensitive transcription factor, p45-NFE2 related transcription factor 2 (Nrf2). Exposure to ultrafine particles also results in alterations of the plasma HDL anti-inflammatory function that could be indicative of systemic proatherogenic effects. This article reviews the epidemiological, clinical and experimental animal evidence that support the association of particulate matter with atherogenesis. It also discusses the possible pathogenic mechanisms involved, the physicochemical variables that may be of importance in the greater toxicity exhibited by a small particle size, interaction with genes and other proatherogenic factors as well as important elements to consider in the design of future mechanistic studies.Extensive epidemiological evidence supports the association of air pollution with adverse health effects -3. It is It is possible that the true relative proatherogenic effects of UFP, compared to the larger 0.1-2.5 μm particles are bigger than can be inferred from our study. When normalized by mass, atherosclerotic lesion scores of UFP-exposed mice were 460% greater than scores exhibited by PM2.5-exposed mice, an extrapolation that is not entirely adequate given that both aerosols overlapped in size. On the other hand, the UFP aerosol contained 44% more particles than the number of sub-0.18 μm particles present in the PM2.5 aerosol which could explain the observed difference, provided that the sub-0.18 μm components accounted for all or most of the PM2.5-induced proatherogenic effects. Any of these extrapolations could enhance the approximately 25% difference in the proatherogenic potentials of UFP versus the larger 0.1-2.5 μm particles. An accurate estimate of the relative potency of UFP vs. 0.1-2.5 μm particles would require a different concentrator technology with selective exposures to UFP and 0.1-2.5 μm particles as well as the use of four parallel exposure groups where both particle mass and particle number concentrations were matched to quantify the relative importance of UFP.One limitation of the SCPC study is that the concentrator technology employed (VACES: Versatile Aerosol Concentration Enrichment System) generates overlapping CAPs aerosols. The fact that the sub-2.5 μm aerosol included UFP made straight comparison with the UFP aerosol difficult since particle mass in the former aerosol was mostly determined by the accumulation mode particles (0.1-2.5 μm). The more abundant UFP contributed to less than a fifth of the PMAn additional limitation of this study is that it only evaluated a single dose at only one time point, which impedes the assessment of threshold, latency of effects or potency. Furthermore, the particles collected in Los Angeles have not been compared to other locations in the world where unique aerosol compositions in each size range could have different outcomes. It will be important to conduct similar studies in different places where the effects of different particle compositions on atherosclerosis, not only size, can be assessed.A number of mechanisms have been proposed to explain the cardiovascular effects of ambient PM Figure , which h2.- production in macrophages, bronchial epithelial cells and lung microsomes incubated with the particles or their organic extracts [in vitro, interfere in the adjuvant effects of DEP in a murine allergen sensitization model [MAPK and NF-κB activities, which are functionally linked to the cytokine and chemokine production in vivo and in vitro [Diesel exhaust particles (DEP) have been used as a model pollutant and extensively studied in airway inflammation. We and others have shown that the pro-inflammatory effects of DEP and concentrated air particles (CAPs), that result in enhancement of allergic inflammation ,48, acutextracts ,52. Moreon model . We haveon model   and quinones, respectively, are most active in the induction of heme oxygenase 1 (HO-1), glutathione S-transferase (GST), and other phase II enzymes that correspond to the first tier of defense in macrophages Figure  and epitarticles . The samter gene . Exposur2,- when undergoing one-electron reductions by NADPH cytochrome P450 reductase to form semiquinones [2.5 or coarse PM at inducing oxidative stress as measured by the dithiothreitol (DTT) assay, extent of HO-1 induction, reduced glutathione to oxidized glutathione (GSH/GSSG) ratios and the ability to cause mitochondrial damage  ,83 in raresidues .How does PM inhalation in the lung lead to the systemic effects on the vasculature?. One possibility is that prooxidant PM deposited in the lungs lead to the release of proinflammatory cytokines Figure  into the10-exposed animals exhibited elevation of polymorphonuclear cells and circulating band cell counts 2 weeks after starting the exposures, with an increase in the size of the bone marrow mitotic pool as assessed by BrdU-labeling [-/- mice. However, a recent study of C57BL6 mice exposed to CAPs for 6 months did result in increased plasma concentrations of inflammatory biomarkers such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), E-selectin and intracellular adhesion molecule-1 (ICAM-1), indicative of systemic inflammatory effects [2.5 exposures also led to increased visceral adiposity and insulin resistance, suggesting a possible link between air pollutants and type 2 diabetes mellitus [-/- mice, Araujo et al showed that CAPs exposures led to the development of dysfunctional HDL with a decrease or loss of its anti-inflammatory properties as exhibited by PM2.5 and UFP-exposed mice, respectively [There is clear evidence that particle deposition can lead to systemic inflammatory events. Suwa et al reported that their PMlabeling . Althoug effects . In thatmellitus . Despiteectively . FurtherPM-mediated generation of dysfunctional HDL could boost and propagate systemic inflammatory effects or at least function as a marker of systemic inflammation. It is well established that plasma HDL cholesterol and apoA1 levels are inversely correlated with the risk for coronary artery disease -89. In aInterestingly, these proinflammatory effects occurred in the absence of significant pulmonary inflammation which raises the possibility that the lungs might not need to be an active player or mediator in the induction of systemic vascular inflammation. Alternatively, particles could be endocytosed by alveolar macrophages Figure , which c2.5 and UFP exposures led to increased hepatic oxidative stress [An alternative possibility is that particles deposited in the lungs get internalized into the cells  and their chemicals could get translocated into the systemic circulation allowing them to reach target tissues Figure . Whethere stress . In addie stress .It is clear that inhaled particles do get deposited in the lungs (step a), with the potential to exert prooxidative effects and activate molecular pathways in response (step b), even in the absence of obvious clinical inflammation (step c). Somehow, systemic vascular inflammation and prooxidative effects follow via a mechanism(s) still to be elucidated. In addition, oxidative stress and inflammation are strongly connected and either one can lead to the other. It is likely that the prooxidant potential of ambient particles determine their ability to activate pathways that lead to prooxidant and proinflammatory effects in the vasculature and promotion of atherosclerosis. However, in spite of this logical inference, it still remains unclear whether PM-induced prooxidant effects trigger or are the consequence of vascular inflammatory effects. Further research is required to elucidate these mechanisms and to prove whether particle-mediated proinflammatory effects are due indeed to its prooxidant potential.A number of factors other than particle size need to be considered to explain why UFP may be more atherogenic than PM 2.5 Table . This in3). Adverse health effects have been correlated linearly with various measures of exposure, without any clear threshold below which PM levels have been found to be consistently safe [2.5 mass, represent > 85-90% of the total PM2.5 particle number [2.5-exposed mice occurred in parallel with a 44% increase in the number of particles < 0.18 μm in spite of a 4-fold smaller PM mass [Exposure to PM has been traditionally assessed by measures of mass per space , one of the key prooxidative components generated in LDL particles. While both DEP and ox-PAPC have been shown to exert prooxidative effects in vascular cells ,59, the The identification of participant gene pathways would pave the way to study gene-environment interactions in the development of PM proatherogenic effects. For instance, it is conceivable that modulation in the expression levels of antioxidant genes as a result of gene polymorphisms could alter the magnitude of effects caused by PM. Indeed, polymorphic variants of the glutathione-S-transferase genes GSTP1 and GSTM1  or HO-1 -/- mice to both whole and particle-free gasoline exhausts results in the induction of aortic metalloproteinases (MMP)-2 and -9 after 7 weeks [Although most of the published data attributes the cardiovascular effects to the particulate matter components, these associations have been questioned on the basis of publication bias. While it is extremely unlikely that publication bias could explain the overall consistency, coherence and strength of those associations ,116, it  7 weeks  and as e 7 weeks . This su 7 weeks . While E 7 weeks  and indu 7 weeks . It is pWe have seen in recent years an enormous improvement in our understanding of the cardiovascular effects of air pollution. Human epidemiological studies together with experimental animal data discussed above support a causal association between air PM and atherosclerosis. Consequently, PM exposure is now considered a novel risk factor . Much woAlthough most of the epidemiological work has been focused on PM mass exposure parameters of the various size fractions, other physicochemical parameters such as chemical composition, particle number, surface area, surface-to-mass area need to be considered in future studies as discussed above. It may require us to develop new parameters or composite metrics that can combine all these various factors to best capture the overall PM-related cardiovascular toxicity. This may help to elucidate why exposure to PM, in strong association with CV events in the Northeast, Midwest and Southern U.S. regions, appears not be associated with excess risk in the Northwestern U.S. regions ,122.Animal data that supports the notion of UFP's greater proatherogenic potential and development of HDL dysfunction are based on one single study  and requWhile exposure to PM leads to both prooxidant and proinflammatory effects, there is a great degree of interconnection in between oxidative stress and vascular inflammation that makes it very difficult to determine whether the induction of vascular oxidative stress precedes or follows inflammation as discussed above. The use of antioxidants as well as transgenics or knockouts for critical antioxidant genes or transcription factors  or prooxidant genes (e.g. NADPH oxidase) may help to clarify this. Since the portal of entry may determine the pathogenic mechanism and the mode for transduction into systemic effects, it will be important to fully characterized the role of the lungs as a mediator and to assess alternative ports of entry such as the gastrointestinal tract by ingestion of particles or skin by contact.Exposure to PM likely leads to important gene-environment interactions that will need to be addressed in both human and animal studies to better define conditions of increased susceptibility. The use of gene profiling, analysis of gene expression by system biology approaches, genetically-engineered animals as well as mouse and human whole genome association approaches are needed to identify genes and/or pathways that either mediate the effects of air pollutants, are influenced by them or could be targeted for intervention in the future.Cumulative epidemiological data support the association of exposure to air pollution with cardiovascular morbidity and mortality, mostly in relation to its particulate matter components. Experimental animal work using hypercholesterolemic rabbits and apoE null mice shows that ambient PM exposure promotes atherosclerosis and that the smaller the particles, the greater the proatherogenic effects. Enhancement of atherosclerosis correlates with the induction of systemic prooxidant and proinflammatory effects although the mechanism for transduction of these effects is not clear. UFP particles may be more toxic based on their greater number, larger content of redox active compounds such as PAHs, greater surface-to-mass ratio and bioavailability of chemically active constituents. Much work is needed to better characterize the main toxic compounds, mechanism(s) of pathogenesis, types of genetic susceptibility that exposed individuals may exhibit, relevant gene-environment interactions in the induction of those effects and development of a biomarker of exposure, degree of damage or susceptibility.The authors declare that they have no competing interests.Both JAA and AEN participated in the conception, design, drafting and critical revision of the manuscript. Both authors read and approved the final manuscript.


C. elegans is unknown outside of 2 highly divergent wild isolates and the canonical N2 Bristol strain.Copy number variation is an important component of genetic variation in higher eukaryotes. The extent of natural copy number variation in Caenorhabditis elegans. Deletions relative to the canonical N2 strain are more common in these isolates than duplications, and indels are enriched in multigene families on the autosome arms. Among the strains in our study, the Hawaiian and Madeiran strains (CB4856 and JU258) carry the largest number of deletions, followed by the Vancouver strain (KR314). Overall we detected 510 different deletions affecting 1136 genes, or over 5% of the genes in the canonical N2 genome. The indels we identified had a median length of 2.7 kb. Since many deletions are found in multiple isolates, deletion loci were used as markers to derive an unrooted tree to estimate genetic relatedness among the strains.We have used array comparative genomic hybridization (aCGH) to detect copy number variation in the genomes of 12 natural isolates of C. elegans, affecting over 5% of the genes in the genome. The deletions we have detected in natural isolates of C. elegans contribute significantly to the number of deletion alleles available to researchers. The relationships between strains are complex and different regions of the genome possess different genealogies due to recombination throughout the natural history of the species, which may not be apparent in studies utilizing smaller numbers of genetic markers.Copy number variation is extensive in  Caenorhabditis elegans [Copy number variation is an important component of genetic diversity in both  elegans  and huma elegans -4 and ha elegans , mental  elegans ,7, and s elegans . Genes i elegans ,2.C. elegans, CB4856 (Hawaii) and JU258 (Madeira) [C. elegans Gene Knockout Consortium we are interested in methods that can help us identify gene deletions more efficiently. Our previous results for CB4856 and JU258 were encouraging, so we examined additional natural isolates to measure the extent of copy number variation in the genomes of less divergent strains. It is important to realize that the C. elegans Gene Knockout Consortium can deprioritize genes affected by deletions in natural isolates in our attempt to generate novel deletions in all genes. As many of the deletions we identify in this study are members of multigene families (see Results and Discussion) the Knockout Consortium can focus on obtaining deletions in members of these families that do not vary among wild type strains.We have previously described extensive copy number variation relative to the Bristol N2 strain ,10 in thC. elegans reproduces primarily through selfing of hermaphrodites, males allow rare outcrossing in the wild at an estimated rate of 1-2% [We also recognized that a large number of indel loci spread throughout the genome might allow us to more thoroughly characterize the relationships among strains, which have been difficult to ascertain due to the limited number of markers used in previous studies. Although  of 1-2% -13. The  of 1-2%  to as hi of 1-2% . Previou of 1-2% ,16. More of 1-2% , indicat of 1-2% .C. elegans in addition to the 2 isolates from our previous work [In this study we have used aCGH to detect copy number variation in 10 natural isolates of ous work ,18. We uWe discovered 510 different deletions among 12 natural isolates, affecting over 5% of the genes in the canonical N2 genome. We found that recombination due to outcrossing in the natural history of the species has caused different portions of the genome to possess different genealogies, such that the relationships among strains are not well represented by a traditional bifurcating phylogenetic tree.alh-2, so that false amplification was ignored in all strains.We performed 10 new aCGH experiments utilizing our exon-centric whole genome microarray [2 fluorescence ratio of mutant:wild-type (log2 ratio) cutoff for amplifications from 1.0 to 0.9 or even 0.8 captured only a modest number of additional amplifications and did not affect the strong bias towards deletions in the strains (data not shown). The bias towards deletions is clearly evident in plots of log2 ratios on each chromosome  and 84 amplifications in the twelve natural isolates. Indel alleles were considered the same if they overlapped and both the leftmost and rightmost affected probes were within 3 probes of each other (see Methods - Strain relationships for details). Amplifications were less robustly detected than deletions due in part to the conservative criteria that we used (see Methods), but this alone does not account for the large preponderance of deletions in the strains. For example, relaxing the logP = 0.0395), but not if RW7000 was excluded from the analysis . With just 8 deletions and 2 amplifications, the mean length of indels in RW7000 (22.6 kb) is greater than in the other strains, due largely to an 86-kb deletion on chromosome IV and a 117-kb duplication on chromosome V. To our knowledge, RW7000 is the only strain in our study with a high Tc1 transposon count [P = 0.0000233), with larger indels on chromosomes V, IV and II. The mean size of indels on each chromosome ranged from 12.8 kb on chromosome V to just 1 kb on chromosome X. Furthermore, a Welch's two-sample t-test revealed a significant difference  between the mean indel lengths on the autosome arms  versus 2 ratio of 1.3) in CB4854, suggesting that copies of the amplified sequence are found elsewhere in the genome and not between the PCR primer sites as in N2.We performed PCR and gel electrophoresis to estimate the false positive and false negative rates of our aCGH indel predictions . This illustrates the power of aCGH experiments to distinguish among strains, since CB3191 had previously appeared identical to N2 based on nearly complete mtDNA sequencing [A single deletion was detected in CB3191 and subsequently confirmed by PCR and DNA sequencing. The deletion completely encompasses quencing . Still, quencing ). In effCB4856 and JU258 were the most divergent strains relative to N2, with more indels and more genes deleted than any of the other strains. KR314 was the most divergent among the other strains and had more deletions on chromosome II than any other strain, including CB4856 and JU258, but curiously had no deletions at all on the left half of chromosome V (V-L) where 18 deletions were present in CB4856 and 23 in JU258. The absence of deletions on V-L suggests the possibility that KR314 reacquired an N2-like V-L through recombination. Interestingly, RW7000 was the least divergent strain other than the N2-like CB3191. This result contrasts with an earlier study stating that RW7000 appeared to be more divergent than 6 of our strains based on the number of alleles in 31 chemoreceptor genes .P < 2.2 × 10-16 and P = 1.281 × 10-5, respectively), after adjusting for the different number of probes targeting each chromosome. As previously described for CB4856 and JU258 [C. elegans are strikingly more common on autosome arms than in the autosome centers or on the X chromosome. The autosome arms span just 38% of the probes on our Whole Genome microarray but include 83% of the indels that we identified (85% of the deletions and 64% of the amplifications).Figure Additional File Many of the indels we detected were found in multiple strains (see Methods - Indel identification). Figure IAS) = 0.072, P < 0.001, see [Table 001, see ) consist001, see ,13,28. IDifferent relationships are predicted by different regions of the genome due to the presence of recombination in the lineage, and this is reflected in the low bootstrap confidence at many of the nodes on the consensus tree. An example of a possible recombination event is indicated in Figure C. elegans [C. elegans F-box and serpentine receptor chemoreceptor families, as well as genes involved in ubiquitination and secreted proteins possibly involved in innate immunity [C. elegans since its common ancestor with Caenorhabditis briggsae [sra and srab families [Genes thought to be involved in sensory perception and innate immunity are enriched in indels in both  elegans  and huma elegans . These gimmunity . Chemorebriggsae , includifamilies , and appfamilies . Higher families  and the families ,32. Convfamilies .We chose to include pseudogenes in Additional File C. elegans [C. elegans genome [Drosophila melanogaster [C. elegans mating system, consisting mainly of selfing, coupled with recurring population bottlenecks due to a demography including frequent extinction and recolonization events [Ne) of C. elegans to a point where selection against deletions cannot overcome stochastic events and the force of genetic drift, which in turn leads to the fixation of more deletions than amplifications as a result of the mutational bias of NAHR. The worldwide Ne of C. elegans has been estimated between 200 and 44,000 [Ne of Drosophila [Ne . Only 5 CB4853 deletions not found in CB4858 were present in any other strains, including 2 deletions on the X chromosome that were found in MY2, and 3 deletions on II-R that were present in CB4854. Four of the 8 deletions found in CB4858, but not in CB4853, were present in JU263 . CB4858 and CB4854 did share deletions in the regions of some of the Haber et al. microsatellites but not in all cases. For instance, CB4858 shared a deletion with CB4853 and CB4856, that is not found in CB4854, which is just 6 kb away from the microsatellite allele shared by CB4858 and CB4854 on II-L. This highlights the importance of using a large number of loci spread throughout the genome when estimating strain relatedness.Different portions of the genome will possess different genealogies due to recombination. Trees are therefore inherently flawed in their generalized depiction of strain relationships when recombination has occurred between lineages, and should not be interpreted as phylogenies. Nevertheless, our results largely agree with other trees inferred from nuclear markers ,16. Straet al. [Another discrepancy between the relationships inferred in our study and those estimated by Haber et al.  involveset al. . JU263 wOverall, CB4856 did not appear particularly closely related to any of the other strains. CB4856 shared the most deletions with KR314, JU322, JU258, JU263 and MY2 , and slightly fewer with the remaining strains (but none with CB3191 and RW7000). However, specific regions of the CB4856 genome more closely resembled particular strains. For example, CB4856 and JU258 shared 5 deletions in common over a 10.6 Mb interval on chromosome V, but each shared only one deletion over the same interval with any other strain (MY2). CB4856, JU258  also share many CB4856 SNP alleles in this portion of the genome ,16. Our retr-1. The log2 ratios for these amplifications (particularly for MY2) indicated a roughly four-fold amplification, suggesting the presence of multiple copies of the retrotransposon.Remarkably, we found 6.7-kb deletions  and duplications (in KR314 and MY2) that affected exactly the same 117 probes on chromosome III. These indels target the retrotransposon Some deletions and amplifications were more common among the strains in our study than the allele observed in N2  in 2002. RW7000 was acquired from the lab of Robert Waterston in 1987 and was submitted by that lab to the CGC in 1991. All other strains were received directly from the CGC and grown for a minimal number of generations prior to DNA preparation. We selected the strains in an attempt to sample a range of the microsatellite diversity observed by Haber et al. , but alsC. elegans genome [2 ratios  were calculated and then normalized using the robust LOWESS regression [http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE19440.Probes on our whole genome microarray were initially selected from build WS139 of the gression  implemengression  with a sgression  and are 2 ratios for all probes are drawn from a normal distribution and begins by considering each probe as an individual segment. The algorithm performs t-tests for all possible mergers of adjacent segments to estimate the probability that the log2 ratios were drawn from samples with the same mean. These P-values are stored in a heap, prioritizing all possible mergers. The data structure is an ordered doubly linked list. The program makes the most likely merger of adjacent segments according to these P-values, calculates the new mean log2 ratio of the segment resulting from the merger, calculates P-values for subsequent mergers of the new segment with its neighbours and updates the heap. This procedure is repeated until the P-value of the next most likely merger is less than a critical value supplied by the user . The program calculates a P-value for each remaining segment using a one-sample t-test. Segments are then labeled as candidate "amplifications" or "deletions" if their both their mean log2 ratios and P-values meet or exceed cutoff values supplied by the user. Segments that do not meet both of these criteria are labeled as "normal". If desired, the program can then merge all adjacent segments sharing the same label, recalculating the mean log2 ratios and P-values for the merged segments. The entire process takes just a few seconds for data sets of 380,000 probes like those used in this study.Indels were detected with a segmentation algorithm developed by S. Flibotte , brieflyP-value ≤ 0.01 were called deletions if the mean log2 ratio of probes in the segment was ≤ -2, and called amplifications with a mean log2 ratio ≥ 1. Most indels that we classified as deletions are probably truly deletions as opposed to insertions in the N2 lineage, since we used probes targeting coding sequences that contain no non-unique 20-mers and no more than 70% homology to other genome sequences. A novel N2 gene arising by duplication and subsequent sequence divergence in the N2 lineage would have to accumulate many coding sequence mutations in order to pass our probe selection filters. N2 genes arising from recent duplications are probably among the 2% of genes not represented on our microarrays. Nonetheless, we cannot completely rule out the possibility that some indels affecting novel N2 genes could have been misclassified as deletions in the natural isolates.Aberrant segments with a P-values were not corrected for multiple tests, but a Bonferroni correction would not exclude many indels since a large majority of them have P-values far below the cutoff . All indels affected 3 or more consecutive probes, with the exception of 10 deletions (~1% of the indels) that were detected by just 2 probes with very negative log2 ratios.2 ratios consistent with an indel and were manually split into multiple segments. After these adjustments, the mean log2 ratios and P-values were recalculated for all segments with one-sample t-tests using R to ensure that our cutoffs were still met. In most cases these adjustments further decreased the P-value of the indels.All aberrant segments were examined manually and some adjustments were made to fine-tune the selection of the leftmost and rightmost probes ("breakpoint probes") within the indels. Some segments were interrupted stretches of probes that did not give log2 ratios outside the normal range for unaffected probes [2 ratios begin to consistently appear again . 78% of these flanking probes were adjacent to their corresponding breakpoint probes, and 90% were within three probes of indels.Occasionally, probes flanking indels show unusual logd probes . This caIndel loci with minimum putative lengths of 250 - 2500 bp were chosen for validation to give PCR amplicons with convenient product sizes. PCR primers were designed to include sequences that aCGH suggested were not included in the indels, but it is possible that some indels may have extended into primer sequences (leading to failed PCR reactions). Loci on all six chromosomes were tested. For each indel locus we tested one or more natural isolates with putative indels within the PCR amplicon, one isolate with no apparent indel, and N2 DNA as a control. All reactions were run with annealing temperatures of 55°C and a 2-minute extension time, with no attempt to optimize PCR conditions. False negatives were considered to be any PCR product found in an isolate with no predicted indel that differed from the N2 band size, whether or not the band size was the same as that found in isolates with predicted indels.t-tests and ANOVA tests were done using R. For the chi-square tests, the expected number of indels on each chromosome was calculated based on the proportion of probes targeting that chromosome, which essentially corrects for differences in length and gene content among chromosomes. Indel lengths were measured from the middle of the left breakpoint probe to the middle of the right breakpoint probe. Indels found in more than one strain were counted multiple times.All remaining chi-square tests, Probe coordinates were obtained by remapping probe sequences to the most recent genome data freeze (WS190) using MegaBLAST, which utilizes a greedy algorithm  to alignet al. (2007) are due to the adjustments we made to the indel breakpoints and because the genes listed in the previous study were extracted from an older genome build (WS150).In order to generate the list of genes affected by indels in Additional File 2 ratios. The single case where we identified deletions and amplifications affecting the same probes could have been treated as a multi-state locus, but this was not done because we chose to exclude amplifications from this analysis.All deletion loci were treated as discrete presence-absence characters. Strains were considered to carry the same deletion allele if their respective deletions overlapped and both their left and right breakpoint probes were within 3 probes of each other, or in a small number of cases (where the breakpoint and flanking probes were more ambiguous) if the breakpoint probes in one strain fell within the region spanned by the flanking probes in another strain. Remarkably, most deletions found in multiple strains according to these criteria had exactly the same breakpoint probes, illustrating the reliability of the logUnrooted trees were inferred from the 510 deletion loci using Phylip 3.66 . The mosIAS) based on the original formulae given by [IAS is 0 at linkage equilibrium. The program tested significance with a Monte Carlo simulation, resampling loci without replacement over 1000 iterations, in order to scramble their order and generate a null distribution of IAS. The P-value is the probability, under the null hypothesis of linkage equilibrium, of IAS being greater than or equal to the value observed for our data set.We used LIAN 3.5  to calcugiven by ,59. IAS JSM, MLE and DGM designed the experiments. JSM performed all experiments and data analyses, prepared the figures and tables and wrote the manuscript. AL assisted in preparing Table S2. MLE provided advice and helped to culture some of the nematodes. SF provided advice and designed the microarray and segmentation algorithm. DGM provided advice and interpretation of data and helped to write the manuscript. All authors have read and approved the final manuscript.Table S1. Indel validations by PCR and gel electrophoresis.Click here for fileFigure S1. Indels in 12 natural isolates of C. elegans.Click here for fileTable S2. Genes affected by copy number variants in C. elegans.Click here for file


The theory of planned behaviour states that attitudinal variables (e.g. job satisfaction) only have an indirect effect on retention whereas intentions have a direct effect. This study uses secondary data from a longitudinal cohort of newly qualified nurses to test for the direct and indirect effects of job satisfaction  and intentions to nurse on working as a nurse during the 3 years after qualification.A national sample (England) of newly qualified (1997/98) nurses (n = 3669) were surveyed at 6 months, 18 months and 3 years. ANOVA and MANOVA were used for comparison of mean job satisfaction scores between groups; intentions to nurse ; working (or not working as a nurse) at each time-point. Indirect and direct effects were tested using structural equation and logistic regression models.Intentions expressed at 6 months to nurse at 18 months were associated with higher scores on pay and relationships, and intentions at 3 years were associated with higher scores on care, development, relationships, work-life interface, resources, pay respectively. Intentions expressed at 18 months to nurse at 3 years were associated with higher scores on development, relationships, education and work-life interface. Associations with actual nursing were fewer. Those working as a nurse had higher satisfaction scores for development (18 months) and relationships (3 years). Regression models found significant associations between the pay and staffing factors and intentions expressed at 6 months to nurse at 18 months, and between pay and intentions to nurse at 3 years. Many of the associations between intentions and working as a nurse were significant. Development was the only job satisfaction factor significantly associated with working as a nurse and just at 18 months.Results partially support the theory of planned behaviour. Intentions expressed by nurses are stronger predictors of working as a nurse than job satisfaction. Retention strategies should focus on identifying nurses showing early signs of departure with emphasis on developmental aspects, mentoring and support. Job satisfaction is a major feature of nursing turnover research  more so behavioural beliefs that influence attitudes towards behaviour, normative beliefs that constitute the underlying determinants of subjective norms, and control beliefs that provide the basis for perceptions of behavioural control.The theory of planned behaviour evolved from the consistent finding that attitudes were poor predictors of behaviour in many circumstances  and propet al. [Two major reviews of nurse turnover  and job et al.  review fTurnover behaviour often emerges as a multistage process that includes attitudinal, decisional and behavioural components . Job satJob satisfaction has been linked to thinking about quitting and intention to search for another job but not to actual turnover of hospital employees . Others This study uses secondary data from a nationally representative (England) longitudinal cohort of nurses who qualified from the diploma programme in 1997/1998 to test the hypotheses that job satisfaction has an indirect effect, mediated through intentions, and has a direct effect on whether a recently qualified nurse was nursing at 18 months and three years after qualification. The direct effects of intentions on actual nursing are also tested.The research design was correlational and longitudinal. Subjects were surveyed prospectively from qualification onwards and at three subsequent time-points .1. Self-reported job satisfaction predicts intentions expressed about working as a UK nurse.2. Self-reported job satisfaction at earlier time-points  predicts working as a UK nurse at 18 months and 3 years after qualification.3. Intentions expressed at earlier time-points predict working as a UK nurse at 18 months and 3 years.If only 1 and 3 are satisfied then self-reported job satisfaction only has an indirect effect on working as a UK nurse and therefore supports the theory of planned behaviour. If 1, 2 and 3 are satisfied then self-reported job satisfaction has both a direct and indirect (mediated through intentions) effect on working as a nurse and only partially supports the theory.Prior intentions predict intentions expressed at subsequent time-points.The study population consisted of all qualifiers from the adult, child and mental health branches of the diploma programme in England in 1997/98. A full census was taken for the child branch because of its smaller size  and becA postal questionnaire was used for data collection. A number of strategies were adopted to maintain response rates. Nurses who attended face-to-face recruitment sessions prior to qualification provided contact addresses  which allowed regular contact. Questionnaires were sent twice to the main address if no response to the first mail-out, and on a third occasion to the alternative address. If no response after the three mailings nurses were traced via the United Kingdom Central Council (UKCC) for Nursing, Midwifery and Health Visiting (now the Nursing and Midwifery Council) and a questionnaire was sent on our behalf by the UKCC.A job satisfaction question was developed for the study, as part of a larger questionnaire, and psychometrically tested on the adult, child, learning disability and mental health branches. The leaThe items that loaded under each factor were consistent across the three remaining branches and time  and factors had good internal reliability . Internal reliability was lowest for work-life interface (0.57–0.66) and highest for education (0.88–0.92). The job satisfaction question also contained two items related to pay and grade. The latter was not asked at 6 months because most nurses were still in D grade posts. Consequently the remaining item on pay was excluded from the psychometric testing because it would result in a single factor however because pay is so important it has been included in the modeling.Until December 2004 newly qualified nurses in the UK were typically appointed to a D Grade post and after a minimum of 6 months post-registration experience would be able to apply for an E grade post. At this grade nurses were often encouraged to gain valuable management experience and/or receive further training in a specialty (e.g. accident and emergency). An increased managerial role was expected of those appointed to F grade posts and these nurses were sometimes left in charge of a ward or other setting. In December 2004 these grades were superseded in the UK by Agenda for Change pay bands .Respondents were asked for example "how likely is it that you will be working in nursing or health care in the UK 18 months from now?" and could respond very likely, quite likely, unlikely, very unlikely or unable to say at this stage. A decision was taken to reduce this categorization into two groups: likely  and unlikely/uncertain .A career chart was used to determine whether or not a respondent was working in a nursing post or as an agency or bank nurse at a particular time-point. On the chart the respondent would provide information on all nursing jobs, other health care jobs, agency/bank work, maternity leave, full-time courses, unemployment, working abroad etc . Each liBasic statistics  were computed to show whether relationships existed between job satisfaction, intentions and working in nursing at 18 months and 3 years. Tetrachoric rather than Pearson correlation coefficients were used to measure association between binary variables . A factor analysis was conducted in SPSS version 15 on job satisfaction data at 6 and 18 months using principal component analysis with varimax rotation and Kaiser normalization to ascertain whether the eight factors  loaded on one or more second-order or higher level factors. In both cases two factors were identified.Analysis of Variance (ANOVA) and Multivariate Analysis of Variance (MANOVA) were used to test for statistical difference in first-order job satisfaction factors between two independent groups (see Key variables above). Single dependent variables were analyzed using ANOVA and multiple dependent variables that loaded under the same factor were analyzed using MANOVA. These two tests provide useful preliminary information before fitting the statistical models described below. High correlation was found between intentions variables that were asked at the same time-point. The tetrachoric correlations between intentions expressed at qualification  ranged from 0.820 (95% CI 0.767 to 0.873) to 0.964 (95% CI 0.946 to 0.982), and the correlation between intentions expressed at 6 months looking ahead to 18 months and 3 years was 0.878 (95% CI 0.841 to 0.915). Due to high correlations, and to avoid collinearity, a decision was taken to include just those intentions variables where the time-point in the future matched with the dependent variable. For example in the model of nursing at 3 years we included intentions at qualification looking ahead to 3 years but not to 6 and 18 months. Similarly we included intentions at 6 months looking ahead to 3 years but not to 18 months. Tetrachoric correlations between successive pairs of working in nursing variables were not as strong and ranged from 0.609 (95% CI 0.519 to 0.699) between qualification and 6 months to 0.073 (95% CI 0 to 0.200) between qualification and 3 years. These variables were therefore retained in all models where they were antecedent to the dependent variable of interest. Therefore in the model for nursing at 3 years we include variables for working in nursing at qualification, 6 months and 18 months.The research hypotheses were tested using structural equation modeling (SEM) and logistic regression. SEM estimates regression coefficients between latent (unobserved) and observed variables that minimize the difference between the covariance structure of the observed data and the predicted model. Logistic regression models predict the occurrence of a binary event using a number of independent variables. SEM was used when job satisfaction was represented by two second order constructs and logistic regression when individual first-order job satisfaction factors were used as independent variables in the model. Each model included seven moderator variables: branch , age, gender, partner, children (living at home), ethnicity  and highest educational qualification , not sufficient for degree entry, Access course or DC test, Other).2 statistic in the logistic regression model.The literature on SEMs is extensive -18 but lThere were an insufficient numbers of respondents for a robust analysis of each branch separately using the methods described above so respondents from all three branches were amalgamated into one dataset. Branch was included as an independent variable in the statistical models and was a significant predictor in just one model where working as a nurse at 18 months was the dependent variable. In that model adult and child branch nurses were less likely to be nursing at 18 months than mental health nurses.Job satisfaction trends were found to vary across branch and time for this sample . The levThis study pre-dated the requirement of MREC approval, guidance was followed from staff of the university from which students were recruited as to the internal procedures required for ethical approval. At no time were participants or Colleges identified. The only addresses held on local databases were those provided by the participant.The data support the secondary hypothesis that prior intentions predict intentions expressed at subsequent time-points. Most nurses  who at qualification said they were intending nurse in the UK at 18 months expressed the same intention at 6 months whereas 66% (73) changed their intentions from unlikely or uncertain  to likely (at 6 months). The corresponding figures looking a head to 3 years were 91% (1783) and 65% (167) respectively. Intentions expressed at qualification and 18 months , and 6 months and 18 months  about working in UK nursing at 3 years produced similar findings. All these associations were statistically significant (Fisher's Exact Test p < .001).Before testing hypotheses involving job satisfaction a decision was taken to second order factor analyse the instrument scores since we could not assume that these factors were the manifestation of a single underlying latent variable. Factor analysis of the 6-month data identified two second-order factors. Client care (rotated loading 0.73), Staffing (0.68), Work-Life Interface (0.56), Resources (0.65) and Pay (0.73) loaded on second-order factor 1(SF1) (variance explained (VE) 30%) and Development (0.79), Relationships (0.81) and Education (0.73) on second-order factor 2 (SF2) (VE 28%). Analysis of the 18-month data identified the same two factors, SF1 (VE 31%): Client care (0.75), Staffing (0.74), Work-Life Interface (0.59), Resources (0.60) and Pay (0.71) and SF2 (VE 26%): Development (0.78), Relationships (0.76) and Education (0.76). In both cases  the Kaiser-Meyer-Olkin measure of sampling adequacy was good , Bartlett's Test of Sphericity was statistically significant (p < .001) and loadings were similar.5,2116 = 2.361, p = .038 SF2: F3,2143 = 2.682, p = .045).A two-group comparison (unlikely/uncertain vs. likely) of mean job satisfaction scores for intentions to nurse at 18 months as expressed at 6 months was used initially to test the primary hypothesis 1 that job satisfaction and intentions to work as a nurse were associated. Mean scores differed significantly on two first-order factors: Pay  and Relationships  and differences approached statistical significance (p < .10) on another three: Development , Work-Life Interface  and Resources  and were similar for the remaining three factors: Client care , Staffing  and Education . First-order factors loading under each second-order factor also differed significantly between intention groups in the MANOVA . At 18 months mean scores differed significantly on four factors: Development , Relationships , Education  and Work-Life Interface , approached significance on another one: pay  and were similar for the remaining three: Client care , Staffing  and Resources  and differed significantly in the two MANOVAs .Differences were more striking for intentions to nurse at 3 years. At 6 months mean scores differed significantly on six factors: Care , Development , Relationship , Work-Life Interface , Resources  and Pay  and were similar for the other two: Staffing  and Education . First-order factors loading under each second-order factors differed significantly between intention groups .A comparison of mean job satisfaction scores between those who were not working as a nurse and those who were working as a nurse at 18 months was used initially to test the primary hypothesis 2 that job satisfaction was associated with working as a nurse. Mean scores differed significantly on one first-order factor only: Development  and mean scores were similar for all other first order factors: Client care , Staffing , Relationships , Education , Work-Life Interface , Resources , Pay . Only those factors loading onto SF2 differed significantly between intention groups .Only one difference emerged for working as a nurse at 3 years for Relationships . All other first order factors did not differ significantly: Client care , Staffing , Development , Education , Work-Life Interface , Resources  and Pay . Intention groups did not differ significantly in either of the MANOVAs (SF1: FAll three intentions to work as a nurse variables were associated with working as a nurse at 18 months (Fisher's Exact test p < .001) and all six intentions variables were associated with working as a nurse at 3 years (Fisher's Exact Test p < .001)Table  and therIntentions accurately predict working as a nurse in the future for those who state very likely or likely (87–92%) but was less effective at predicting those not working as a nurse in the future amongst those who stated very unlikely, unlikely or unable to say at this stage (26 – 39%).The final stage of analysis focuses on the modelling of intentions and working as a nurse. The relationships between intentions expressed at earlier time-points and current intentions were all statistically significant Table  and therWhether a respondent was working as a nurse or not was also significantly associated with intentions expressed at earlier time-points and therefore supports primary hypothesis 3.The evidence supporting an association between job satisfaction and intentions is conflicting (primary hypothesis 1). At 6 months looking ahead to 18 months neither of the second-order factors was associated with intentions in the SEM whereas the logistic regression found significant associations for Staffing and Pay. The global effect of Care, Staffing, Work-Life Interface, Resources and Pay however falls short of statistical significance (p = .059). An odds ratio (OR) less than one for the Staffing was an unexpected finding. Tolerance, defined as the amount of variation not explained by the other seven job satisfaction factors, ranged from 0.57 to 0.79 amongst the job satisfaction factors therefore the finding for Staffing cannot be attributed just to collinearity and, as was shown previously, satisfaction with staffing was marginally lower for those who were likely to nurse at 18 months than those who were unlikely or unable to say at this stage when asked at qualification (3.28 vs. 3.33).Greater consistency emerges between the SEM and logistic regression models when nurses were asked to look ahead to the 3-year time-point. The association between SF1 and intentions at 3 years for the 6-month data was significant (OR 1.56 95% CI 1.02 – 2.48) in the model that did not include prior intentions and working as a nurse at 6 months and was close to statistical significance in the full model (Table SF2 had a stronger association than SF1 with intentions at 3-years in the model for the 18-month time point. SF2 was significantly associated with intentions in the model that excluded prior intentions and working as a nurse at 18 months (OR 1.76 95%CI 1.12 – 2.76) and close to significance in the full model (Table SEM is able to include more respondents in the model because each first-order job satisfaction factor is treated as a dependent variable and is modelled under the missing at random assumption (MAR) whereas in the logistic regression model these factors are treated as independent variables. The number of nurses can be increased in the logistic regression analysis by the simultaneous regression of the intentions and working as a nurse variables on their antecedents (where appropriate) and the baseline moderators. Using this approach it is possible to increase all the analysis samples from 2045 to 2238/2039 and 1553 to 1820. The findings for job satisfaction in these models remain largely unaltered.Intentions to nurse at 18 months, as expressed at both qualification and 6 months were both positively associated with working as a nurse at 18 months Table  and therSecond order factors were not associated with nursing at 18 months whereas the global test of first order factors loading on SF2 on nursing at 18 months was statistically significant (p = .023) and can be attributed to the positive association with Development and negative association with Relationships. These two first-order factors appear to have a counterbalancing effect on working as a nurse at 18 months. There is some evidence for supporting primary hypothesis 2 but it is not strong. All intentions except those expressed at 18 months looking ahead to 3 years were not significantly associated with working as a nurse at 3 years so the evidence is conflicting in regard to primary hypothesis 3 although one would expect this latter variable to have the strongest effect because of the shorter time lapse. Neither the second order nor the first order job satisfaction factors were associated with working as a nurse at 3 years and therefore there is little support for primary hypothesis 2. Not surprisingly working as a nurse at 6 months and 18 months were both significantly associated with working as a nurse at 3 years. Increasing the number of nurses contributing to the logistic regression analysis under the assumption of MAR by simultaneously modelling the independent variables did not change the overall findings.A finding that was consistent across all models was the increasing strength of relationships the nearer the expressed intentions were to the time-point of interest. Only one moderator variable – ethnicity – had a significant association in the majority of models (4 out of 5). Those who were white British or Black, Asian and Chinese were more likely to intend to work as a nurse in the UK in the future than those from other ethnic groups  however nurses who were Black, Asian and Chinese or white Irish were less likely to be working as a nurse at 3 years. Nurses with a spouse or partner at qualification were less likely to be working as a nurse at 18 months than those without, a finding that was not replicated at 3 years.We complete the analysis by fitting each of the five models shown in Tables The findings from this study support the view that intentions are a better predictor of turnover than job satisfaction as shown elsewhere  althoughemotional support from immediate line-manager, would sometimes  load on the development factor rather than the relationships factor.The data partially support an association between job satisfaction and nursing turnover at 18 months but not at 3 years. The latent variable or second-order factor represented by Development, Relationships and Education had a positive but non-significant association with nursing at 18 months whereas the global effect of these three first-order factors in the logistic regression was significant. Most of this can be attributed to the comparatively strong positive association between turnover and Development and confirms what was previously found by Shields and Ward  that tra Research on job satisfaction and turnover has been contradictory. Some have found that job satisfaction only has an indirect effect on turnover  often beJob dissatisfaction has been identified as a major predictor of intent to leave  and in tSatisfaction with staffing at 6 months was negatively, rather than positively associated with intention to quit at 18 months in this study. Why this particular finding arose in this study is difficult to ascertain. An extensive body of work from the US shows strong associations between dissatisfaction and increasing patient load . Nurses By 18 months development and education have become more important and pay less so. The findings for the SEM and logistic regression models were generally supportive of each other. There may be a connection here with the emergence of development in the intentions model at 18 months (looking ahead to 3 years) and the model for working as a nurse at 18 months.Ajzen  suggestsEthnicity was the only distal variable that was consistently associated with intentions and turnover. Black, Asian and Chinese indicated they were as likely as other groups to nurse in the future however a higher proportion were no longer working as nurses at 3 years. An analysis of NHS nursing staff survey data collected in 1994  also fouIn summary we found strong relationships between intentions and turnover, evidence of a relationship between development and turnover in one model and evidence of relationships between a small number of first-order job satisfaction factors and future intentions with pay being the only factor to emerge on more than one occasion. These findings are in tune with those arising from a meta-analysis of job satisfaction and turnover of nurses conducted by Irvine and Evans  althoughA framework analogous to the theory of planned behaviour was followed. The secondary nature of the analysis limited us to certain variables. We were therefore not able to include variables for subject norms and perceived behavioural control. Future longitudinal work of nurse's early career would therefore benefit from the inclusion of these two salient beliefs.The data analysed are longitudinal and suffer from attrition. The data were modelled under the assumption of MAR by including moderator variables in the model known to be associated with attrition . However it is possible that the non-response mechanism was non-ignorable therefore some biases remain. We chose to use an instrument that was specifically developed for nurses in early career. Other instruments may have produced different findings. Some studies  have fouThe aim of this research was to test whether job satisfaction had a direct effect on both intentions and working as a nurse and whether intentions predicted working as a nurse in the future. There was limited evidence for a job satisfaction effect on intentions and working as a nurse. Pay was the only factor, apart from staffing on one occasion, to have a direct effect on intentions. There was partial evidence of a direct effect of job satisfaction on working as a nurse via development that was transitory. Lack of development in early career may well lead to a loss of newly qualified nurses. It has been found that newly qualified nurses reach a low point at around six months ,40-42 anThis work was undertaken by the National Nursing Research Unit, which receives funding from the Department of Health (DH). The views expressed in this publication are those of the authors and not necessarily those of the DH.TM participated in study design, was involved in data processing, carried out the analysis, drafted the manuscript and the interpreted the findings. SR made a major contribution to the conception of the study, the design, data collection and interpretation. PG provided intellectual and theoretical input for the paper and interpretation of the findings. All authors were involved in revising the manuscript and have read and approved to final version.


One needs to think outside of the box, as one of us  learned from many years as a mathematician, and a biophysicist.+ cells is essential.In this short Review, the need to focus on producing high levels of neutralizing antibodies (NAbs) to incoming and conformationally altered virus after it has bound to CD4Increasing the number of gp120 molecules on the surface of L-2 particles, could allow for an enhanced number of NAbs.+ T cell responses in recent vaccine trials has not worked perhaps because it may have allowed HIV to enter into remote sanctuaries. Our approach focuses on increasing NAbs, before high levels of CD8+ T cells are produced.The attempt at increasing CD8 It has now become a frequent ritual to read of the newest clinical trial failure and yet the same paradigm goes on . Most reDespite this set-back, trials are starting this Fall using a similar strategy. What is wrong is that vaccinology is not only a science but an art and one needs to take a step back from using the same failed approaches.We propose that one needs to think differently by presenting defective HIV particles L-2) which contain 7 to 10-fold more gp120 spikes on their surface in a prime (plasmid pL2)-boost  building multi-clade Env expressing particles. The new constructs would include Clades C, AE and circulating recombinant forms (CRFs) from China and Africa ,10 Envs Simultaneously an intranasal spray is to be administered in order to protect CD4 T-cells in the GALT. The rapid targeting of HIV to the gut mucosa has been well demonstrated in monkeys and recent results show it is only necessary but not sufficient for disease .The properties of L-2 particles are depicted in Table In the model proposed we are thinking about HIV vaccination in a different way. It is important to elicit neutralizing antibodies , protectSeveral years ago, Drs. Ikuta and Goto discovered a sub-line of HIV-infected cells producing protease deficient defective particles that they called L-2  and Fig . Figure After many years we learned from monkey studies performed by the New England Primate and Harvard groups that mutated SIV will eventually revert back to wild type. However, L-2 particles have 8 mutational differences from HIV  declare that they have no competing interests.RBL drafted MSS. QZ performed experiments related to MSS.