To assess microleakage in conservative class V cavities prepared withaluminum-oxide air abrasion or turbine and restored with self-etching oretch-and-rinse adhesive systems.Forty premolars were randomly assigned to 4 groups  and class V cavities were prepared on the buccal surfaces.Conditioning approaches were: groups I/III - 37% phosphoric acid; groups II/IV-self-priming etchant (Tyrian-SPe). Cavities were restored with One StepPlus/Filtek Z250. After finishing, specimens were thermocycled, immersed in 50%silver nitrate, and serially sectioned. Microleakage at the occlusal and cervicalinterfaces was measured in mm and calculated by a software. Data were subjected toANOVA and Tukey’s test (α=0.05).Forty premolars were randomly assigned to 4 groups  and class V cavities were prepared on the buccal surfaces.Conditioning approaches were: groups I/III - 37% phosphoric acid; groups II/IV-self-priming etchant (Tyrian-SPe). Cavities were restored with One StepPlus/Filtek Z250. After finishing, specimens were thermocycled, immersed in 50%silver nitrate, and serially sectioned. Microleakage at the occlusal and cervicalinterfaces was measured in mm and calculated by a software. Data were subjected toANOVA and Tukey’s test (α=0.05).Marginal seal of cavities prepared with aluminum-oxide air abrasion was differentfrom that of conventionally prepared cavities, and the etch-and-rinse systempromoted higher marginal seal at both enamel and dentin margins. Aluminum oxideair abrasion is one of the methods used for the preparation of conservative cavitydesigns. Air-abrasive technique using a high-speed stream of purified aluminum oxideparticles delivered by air pressure for removal of tooth structure was reintroducedwiththe intention to eliminate pressure, heat, noise and vibration associated with rotaryinstruments, and to reduce pain, allowing preparation with less need for localanesthesia20.The concept of cavity preparation has been modified and/or replaced by more conservativepreparations due to the use of new techniques and restorative materials that preservesound tooth structure by minimizing the necessity to enlarge the cavitypreparation23.Contemporary restorative techniques are based on the adhesive properties of resin-basedmaterials. The basic mechanism of bonding to enamel and dentin is an exchange processinvolving replacement of minerals removed from the hard tissue by resin monomers thatupon setting become micro-mechanically interlocked in the created porosities23. However, these systems produce a deep demineralized area,without the certainty of complete infiltration of monomers into the exposed collagenfiber mesh, thus affecting the longevity of adhesion12.Following an etch-and-rinse approach, the tooth is first etched and rinsed off. Thisconditioning step treats enamel and dentin with inorganic acid (mostly 30-40% phosphoricacid), promoting the increase of the permeability and the demineralization of enamel aswell as dentin 19. This techniqueavoids the formation of extensive demineralized areas, which may not be fullyimpregnated by monomers24. Accordingto the literature, the incorporation of smear layer to the adhesive interface can resultin a more defective adhesion area12.Self-etching adhesives use non-rinse acidic monomers that simultaneously condition andprime dentin, eliminating the acid-conditioning step and reducing the techniquesensitivity7. The behavior of restorative materials in cavitiesprepared with aluminum oxide air abrasion has been extensively investigated25, and, in general, differences have notbeen observed between the restorations of cavities prepared with air abrasion or turbinefollowed by acid conditioning25. The restorations that did not receiveacid conditioning after preparation with air abrasion presented increase inmicroleakage8. In addition,better marginal seal has also been observed in enamel margins of cavities prepared withair abrasion21.The most cited reasons for failure of adhesive restorations placed with earlieradhesives are loss of retention and marginal adaptation8 reporting theeffectiveness of self-etching adhesive systems in the sealing ability of cavitiesprepared with air abrasion. Thus, the present study evaluated in vitrothe degree of microleakage in conservative cavities prepared with air abrasion andrestored using a self etching adhesive system. The hypothesis of this study was thatconservative class V cavities prepared with air abrasion and restored with aself-etching primer have less marginal microleakage.Despite the advances in restorative dentistry, there is only a limited number ofstudiesThe research protocol was approved by the Research ethics Committee of RibeirãoPreto Dental School, University of São Paulo (process # 2003.1.312.58.9).Forty sound human premolars, extracted within a 6-month period and stored in 0.9% salinesolution at 4°C, were examined to confirm the absence of defects in enamel and dentin,and selected for the study. Teeth were carefully cleaned with a hand scaler andwater-pumice slurry in prophylaxis rubber cups, and randomly assigned to 4 groups(n=10), according to the cavity preparation method and conditioning approach. Theexperimental groups were as follows: Group I: Air abrasion + Phosphoric acid; Group II:Air abrasion + Self-priming etchant; Group III: Turbine + Phosphoric acid; Group IV:Turbine + Self-priming etchant.Forty non-carious class V cavities were prepared on buccal surfaces with the occlusalmargin located in enamel and cervical margin in dentin/cementum. The cavity outline waspreviously traced on surfaces with a OHP marker pen, to define a uniform size . The depth of the cavity wasapproximately 1.5 mm, as measured with a premarked periodontal probe.Following the pre-defined dimensions The airabraded cavities were prepared with theair-abrasive system Mach 4.1  with aluminum oxideparticles of 27.5 mm under 60 psi pressure with an intensity of 4 g/min at continuousmode, delivered by a 0.011-inch nozzle opening, with a 90° angle with the tooth surface.The application distance was standardized using a custom designed apparatus consistingof a moving holder that positioned the handpiece in such a way that the aluminum oxideparticle stream was delivered at a constant distance of 2 mm from the delimited surfaceof the specimen. The specimens were fixed with wax at a semi-adjustable base. Theoperator manipulated the apparatus' screws in such way that the semiadjustable base withthe specimen was moved in right-to-left and forward-to-back directions, thereby allowingthe stream to provide a more accurate application of the entire delimited site. Afterthe stream application, the specimen was removed and the cavity was rinsed for 30 s, andthen gently dried with oil-free compressed air.For cavities prepared with turbine, a #330 carbide bur was used  at a high-speed handpiece  under water spray.Cavity finishing was done with the same bur at a low-speed handpiece. The enamelcavosurface angle was beveled with a #1195-diamond bur.After cavity preparation, the enamel/dentin surfaces were conditioned according to theexperimental group. Specifications of the materials employed for surface treatment areshown in 2 output . Thecavities were restored with a hybrid light-activated composite resin , inserted in three increments (maximum thickness of 2 mm). The first twoincrements were applied obliquely against the occlusal and the gingival walls,respectively. The final increment was inserted following tooth contouring. eachincrement was light-cured for 40 s with the same visible light-curing unit.Following this, One-Step Plus adhesive system  was applSpecimens were stored for 24 h in distilled water at 37°C and then the restorations werepolished with Super-Snap disks  in a decreasing abrasiveorder. All cavity preparations, restorations and finishing procedures were performed bythe same operator.The specimens were subjected to a thermocycling regimen of 500 cycles between 5°C and55°C waterbaths. Dwell time was 1 min, with a 3-s transfer time between baths. Inpreparation for the dye penetration test, the teeth were dried superficially, had theapices sealed off with epoxy resin and the entire tooth received two coats of nailvarnish, except for a 2-mm window around restoration margins. As the nail varnish dried,the teeth were immersed in distilled water for 2 h, and then immersed in a 50% aqueoussilver nitrate solution for 8 h, kept in a light-proof container. Next, the teeth wererinsed thoroughly in tap water and the nail varnish was entirely removed with a sharpinstrument.The specimens were embedded in chemically activated acrylic resin  and sectioned longitudinally in a mesiodistal directionwith a water-cooled diamond saw, in a sectioning machine . Then, they were embedded again in acrylic resin blocks andsectioned in a buccolingual direction, providing two to three 1.0-mm-thick sections foreach tooth. Then, the sections were exposed to the light of a photoflood lamp for 20 min to reveal the silver nitrate, which, exposed to light, acquires a darkcolor, allowing the visualization of the tracer-penetrated areas. The sections wereinitially thinned in a polishing machine (Struers A/S) with 180- to 600-grit siliconcarbide paper, and then manually smoothed with 1000- to 1200-grit SiC paper to obtain aflat surface and a final thickness of approximately 0.25 mm.The cuts were identified and carefully fixed on microscopic slides, and the margins wereanalyzed separately; each margin was viewed under a x5 magnification optical microscope connectedto a digital camera . The images obtained were transmitted to a personal computer and, afterdigitization, they were analyzed by Axion Vision 3.1 software (Carl Zeiss Vision GmbH),which performs a standardized assessment of the tracer’s extent along thetooth-composite-interface and allows a quantitative measurement in millimeters. The dyepenetration depth along the cavity wall of each cut was measured. Microleakage at each interface was obtained by calculating theratio  of the tracer penetration along the tooth-restoration interfaceand the total length of the enamel and/ or dentin interface. Tracer penetration atenamel and dentin interfaces was calculated separately for each section, and then themean for each tooth was determined.Data were analyzed statistically by three-way ANOVA followed by Tukey’s test forpair-wise multiple comparisons at a 0.05 significance level.The means of dye penetration and standard deviations at both interfaces for eachexperimental group are shown in Three-way ANOVA revealed statistically significant differences (p<0.05) for themargin types and conditioning approaches (p<0.05), and that the margin in enamel andtotal-etching system had significantly lower microleakage.Analyzing the interaction of factors, the etch and-rinse system showed statisticallysignificant difference (p<0.05) between enamel and dentin/ cement margins in theair-abraded cavities, but not in the bur-prepared cavities. Groups II (air abrasion +Tyrian SPe) and IV (turbine + Tyrian SPe) showed higher microleakage degrees on bothmargins and different significantly from groups I and III.9. In addition to these factors, thepermanence of aluminum oxide particles on the abraded surface can also influence thepenetration of the adhesive. A scanning electronic microscopy study22 revealed that the morphology of theadhesive interfaces of the lateral walls of airabraded cavities was similar to theobtained with bur-prepared. However, the adhesive interfaces of the pulpal walls weremore irregular in the air abrasion preparations. Several studies25 have found a decrease in marginal sealin cavities prepared with air abrasion, mainly when 27-µm-diameter particles wereused6. Another important aspectto be observed in the present study is that the absence of finishing in cavitiesprepared with air abrasion probably no interferes in the adaptation of the restorativematerial. Corona, et al.4 (2001)verified that air abrasion preparation do not promote a well define contour in cavitymargins and walls that can adversely influence in the marginal seal of therestorations.The findings of this work showed that air abrasion technique for cavity preparationsprovided different seal at the margins of composite resin restorations compared theturbine. This fact may be due to the macro and microscopic irregularities in the abradedsurface, which may have influenced in the mechanical interlocking. Moreover, theroughened surface resulting from air abrasion preparation limits the penetration of theadhesive agent when this modified surface is not etched with acid26 which report better behavior of enamel surface as foradhesive resistance as for marginal microleakage.In the present work, differences were observed between enamel and dentin/cementummargins, only for phosphoric acid. This could be ascribed to morphological andstructural differences of the substrates, as well as their distinct composition. Suchresults corroborate the findings of the literature5. In spite of the care with regard to this factor, Class Vrestorations present a relatively small factor C that results in less stress in theadhesive interface, creating less gaps and subsequent less microleakage14.Another important aspect that must be taken into account is the polymerization shrinkageof the resinous restorative material. Despite conservative preparations and theincremental composite insertion technique, as performed in this study, thereby reducingthe amount of material and the polymerization shrinkage, it was not possible thecompletely seal both cavity margins. It is known that the resultant stress ofpolymerization shrinkage of composite resin can generate tensions between therestorative material and tooth substrate, which, consequently, can generate gaps in theadhesive interface. This stress depends on some factors, such as the cavityconfiguration (factor C), and can reach around 10 to 15 MPa3. At dentin, this acid completely removes the smear layer,demineralizing the peri- and intertubular dentin, widening dentinal tubule openings andincreasing the permeability of this substrate17.In the overall and independent analysis of the studied factors, the surface treatmentwith the etchand-rinse system provided better marginal seal than the self-etchingsystem. This fact may be explained by the surface morphological pattern created afterphosphoric acid application. At enamel, this acid promotes a demineralization, whichproduces an intra- and interprismatic dissolution that results in irregularities,through which the adhesive agent can flow and form a micromechanical interaction due tothe formation of resinous tags after its polymerization9 (2004),tooth surface treatment with self-etching agents does not remove the smear layersignificantly, since it is not carried through the washing of the surface, remainingsome regions without treatment13. Inaddition, selfetching systems consist of weak acids The reactive components in theprimers of these systems consist of phosphates derived from hydrophilicmonomers10 that are able totreat and penetrate simultaneously in the enamel surface, but not in a homogeneousway9.According to Hannig, et al.18. Indentin, it is known that a conditioning agent with low pH, as phosphoric acid, providesmore demineralization1.In this study, for both preparation methods, enamel margins showed higher microleakagevalues when the self-etching system was applied. A feasible explanation for suchbehavior is the lower capacity of these systems to etch as 35% or 37% phosphoric acid,due to the relatively higher pH of these selfetching agents (1.5 - 3.0) as compared tophosphoric acid (pH 0.02 – 0.42)15.At dentin/cementum margins, this study disclosed that the conventional preparation withturbine, associate to the etch-and-rinse system, still could not be replaced by airabrasion preparation. The particle stream acts indiscriminately in the organic andinorganic portions of the substrate, leading to surface roughness and tubuleobliteration, and consequently absence of resinous tags, compromising the adhesive layerand the marginal sealThe findings of this study revealed a distinct behavior of the adhesive systems, andshowed that the aluminum oxide air abrasion did not influence significantly the marginalseal of conservative class V restorations, with improved results in enamel after acidetching. It is important to emphasize that, clinically, no matter its length, thepresence of significant leakage is the problem. Also, the intrinsic aspects related toadhesive systems, such as the pretreatment technique required, composition and mechanismof adhesion, may decisively influence their effectiveness in sealing cavity margins andpreventing marginal microleakage.Comparison with the literature is difficult due to the lack of studies assessing thefactors studied in this work. Thus, further studies are necessary to investigate theproperties of restorative materials as well as other aspects of cavity preparation andtooth conditioning.Based on the results obtained in this study, it may be concluded that: conditioning ofenamel and dentin with phosphoric acid provided better marginal seal than theself-etching approach; marginal seal of class V cavities prepared with air abrasion wasdifferent from that of conventional turbine preparation; there was higher marginal sealof enamel margins than dentin/cementum margins for groups I and III.


Vancomycin-resistant enterococci (VRE) are among the most common antimicrobial-resistant pathogens causing nosocomial infections. Although antibiotic use has been identified as a risk factor for VRE, it remains unclear which antimicrobial agents particularly facilitate VRE selection. Here, we assessed whether use of specific antimicrobial agents is independently associated with healthcare-associated (HA) VRE rates in a university hospital setting in Berlin, Germany.We conducted the study between January 2014 and December 2015 at the Charité-university hospital of Berlin, Germany. From the hospital pharmacy, we extracted data for all antibacterials for systemic use -classification J01) and calculated ward specific antibiotic consumption in defined daily doses (DDDs) per 100 patient-days (PD). We used the microbiology laboratory database to identify all patients with isolation of invasive or non-invasive VRE and calculated HA-VRE incidence as nosocomial VRE-cases per 100 patients and HA-VRE incidence density as nosocomial VRE-cases per 1000 PD. We defined VRE isolates as hospital-acquired if they were identified three days or later after hospital admission and otherwise as community-acquired (CA-VRE). We performed univariable and multivariable regression analyses to estimate the association of the frequency of HA-VRE per month with antibiotic use and other parameters such as length of stay, type of ward or presence of at least one CA-VRE on ward. In a second analysis, we considered only patients with VRE infections.We included data from 204,054 patients with 948,380 PD from 61 wards. Overall, 1430 VRE-cases were identified of which 409 (28.6%) were considered hospital-acquired (HA). We found that carbapenem use in the current month and prior-month use of glycopeptides increased the risk for HA-VRE by 1% per 1 DDD/100 PD and 3% per 1 DDD/100 PD, respectively. However, when only VRE from clinical samples were considered, only glycopeptide use showed a statistically significant association. In both models, detection of at least one patient with CA-VRE on a ward in the current month significantly increased the risk of HA-VRE, thereby indicating nosocomial spread of VRE.Our findings suggest that the risk of HA-VRE is associated with specific antimicrobial agents. Prudent use of these antimicrobial agents might reduce nosocomial VRE rates. That appearance of at least one CA-VRE case on the ward increased the risk of HA-VRE detection highlights the importance of strict hand hygiene practices to interrupt person-to-person transmission of VRE. Vancomycin-resistant enterococci (VRE) are emerging worldwide and are among the most common antimicrobial-resistant pathogens causing nosocomial infections –4. SinceSo far, several risk factors for VRE colonization or infection have been identified, such as long periods of hospitalization, immunosuppression, serious comorbid conditions, close proximity to patients infected or colonized with VRE as well as antibiotic use , 8–12. ATherefore, the primary objective of the study was to investigate whether use of specific antimicrobial agents is independently associated with nosocomial VRE rates in a university hospital setting in Berlin, Germany. Secondary objective was to identify other risk factors that are associated with nosocomial VRE rates.This study was conducted at the Charité-university hospital of Berlin, between January 2014 and December 2015. The Charité is a tertiary care center with more than 3000 beds and more than 140,000 inpatient cases per year.E.) faecium- or E. faecalis-isolates from intensive care units (ICUs) and surgical, medical and hemato-oncological wards. In case of screening samples, selective chromogenic medium  and VITEK 2 system (bioMérieux) were used, while clinical samples were processed following standard procedures dependent on specimen type. Results were interpreted according to European Committee on Antimicrobial Susceptibility Testing definitions . A molecular characterization of the VRE isolates was not performed.From the microbiology laboratory database of Charité we prospectively identified patients with vancomycin-resistant Enterococcus  if they were identified three days or later after hospital admission and otherwise as community-acquired (CA-VRE). In patients with multiple VRE isolates during the same hospital stay, only the first identified isolate was considered. We included isolates irrespective whether they were obtained for infection control surveillance or recovered from clinical specimen and irrespective whether they were associated with colonization or infection.At the Charité, a targeted risk adjusted screening policy is implemented: in patients in whom a VRE has been isolated within the previous three years, a rectal swab is obtained at admission. However, during the study period eight (non-ICU) wards performed an intensified admission screening that involved all patients irrespective of underlying risk factors. In this ecologic study, we did not collect data on compliance with the screening policy or compliance with hand hygiene or cleaning procedures on the respective wards.Antimicrobial agents were classified according to the anatomical therapeutic chemical (ATC) system (34). From the pharmacy of Charité, ward specific data on antibiotic consumption were converted into defined daily doses (DDDs) and reported as DDD/100 patient-days (PD) at monthly intervals. We collected data for all antibacterials for systemic use (ATC-code J01). Data on antifungal or antiviral medication were not considered.For this ecologic study, we analyzed aggregated and anonymous data that were collected by the hospital in accordance with the German “Protection against Infection Act”, §23. Therefore, ethical approval and informed consent were not required and institutional review boards were not consulted.We calculated median and interquartile range (IQR) for the total study period (24 months) for the following variables: number of patients, patient-days (PD), average length of stay (LOS), number of beds per ward, bed occupancy rate, month of VRE-detection, HA-VRE rates and antibiotic use. HA-VRE incidence was calculated as nosocomial VRE-cases per 100 patients and HA-VRE incidence density as nosocomial VRE-cases per 1000 PD. We reported data for all wards as well as stratified by type of ward . Differences in baseline characteristics between different types of wards were compared by using the Kruskal-Wallis test. Univariable and multivariable regression using generalized linear models was performed to estimate the association of the frequency of HA-VRE per month with different antimicrobial groups in the current month and the month before the current month and further confounding parameters such as length of stay (LOS), bed occupancy (patient days/bed places on ward available), type of ward and at least one patient with community-acquired VRE on ward in the current month. In addition, we added a variable that took the different screening policies  into account. Since observations within a ward are not statistically independent due to the diagnostic and management policies , adjusted incidence rate ratios (IRR) with 95% confidence intervals (CI) were estimated. They were based on generalized estimating equation (GEE) models which account for this clustering effect by using an exchangeable correlation structure (35).p < 0.2 in the univariable regression model were included in a full model and then non-significant parameters were excluded stepwise. The selection criterion was the smallest Chi-square value and p ≥ 0.05 in the type III score statistic. The quasi-likelihood information criterion (QIC) as a modification of the Akaike information criterion (AIC) was used as goodness-of-fit measure in the GEE model. We calculated two models. The first model considered all identified HA-VRE isolates  the second model considered only clinical specimen. Antimicrobial agents that are relevant for the treatment of VRE, such as daptomycin, linezolid and tigecyclin were excluded from the analysis. Additionally, spearman correlation coefficients were calculated between the antibiotic use and the incidence density of HA-VRE for the entire study period (24 months). P-values less than 0.05 were considered significant. All analyses were performed using SPSS  and SAS 9.4 .We used negative-binomial distribution instead of Poisson distribution because the variance exceeds the mean and overdispersion was observed. The Lagrange multiplier test was used to test whether the negative binomial model significantly differs from the Poisson model. The log number of patient days during each month was used as an offset in the model. All parameter with From 61 wards  we included data from 204,054 patients with 948,380 patient-days. Median length of stay was 4.7 days  and was statistically significant higher in ICUs and hemato-oncological wards as compared to surgical wards  were considered hospital-acquired. Of those, 238 (58.2%) HA-VRE were identified in 2015. The median HA-VRE incidence and HA-VRE incidence density in all 61 wards was 0.11  and 0.24 (0.07–0.54), respectively  DDD/100 PD. Antibiotic use ranged from 64.1 DDD/100 PD on medical wards to 163.2 DDD/100 PD on ICUs , glycopeptide use  and use of third-generation cephalosporines  showed a strong correlation with HA-VRE incidence density , see Table p < 0.01). In addition, type of hospital ward , detection of at least one patient with CA-VRE in the current month, an intensified screening policy and the year 2015 were independently associated with higher VRE rates.The first multivariable regression model  indicated that carbapenem use in the current month independently increased the risk for HA-VRE by 1% per 1 DDD/100 patient-days (incidence rate ratio (IRR), 1.01; 95% confidence interval (CI) 1.00–1.02, The second multivariable regression model considering only VRE from clinical specimen showed that glycopeptide use in the previous month  were the only antimicrobial agent that was statistically significant associated with HA-VRE (see Table In both multivariable models, size of ward, length of stay and bed occupancy rate were no independent risk factors for HA-VRE in the final models.Antibiotic use is one of the most important risk factors for VRE occurrence within the hospital setting . AlthougIt is unclear, why among antimicrobial groups only glycopeptides but not carbapenems were associated in both models with HA-VRE rates. A possible explanation is that glycopeptide use constitutes only a first step in the selection process of VRE: Although glycopeptide exposure does not promote emergence of VRE through genetic mutations in individual patients, it might facilitate selection of intestinal VRE , 13. In In fact, Donskey et al. showed that in patients colonized with VRE exposure to antimicrobial agents with activity against Gram-negative bacteria or with anti-anaerobic activity leads to a rapid increase of intestinal VRE density, whereas discontinuation of these antibiotics decreased VRE density . Since fIt is also unclear, why carbapenem use in the current but not in the prior month was associated with HA-VRE-rates when screening and clinical specimen were considered. However, given the available evidence it seems unlikely that a single antimicrobial agent is responsible for the multifactorial process of VRE selection. It is rather an interaction of different antimicrobial agents with the competing intestinal microbiota and might differ from individual to individual .Regarding antibiotics, the use of broad-spectrum antibiotics such as glycopeptides and carbapenems was 3 to 13-fold higher on ICUs as compared to medical or surgical wards. Although interpreting these results without individual patient data is challenging, this rates might indicate inappropriate use of these antibiotics on ICUs. Antibiotic stewardship could limit unnecessary or inappropriate use of antibiotics, thereby improving the quality of antibiotic use in hospitals .In addition to glycopeptides and carbapenems, we found that hospitalization on an ICU as well as detection of CA-VRE increased the risk of HA-VRE acquisition. These results are in line with other studies that found that hospitalization on ICUs or severe underlying comorbidities and immunosuppression are risk factors for VRE colonization or infection , 12, 25.The fact that HA-VRE cases increased from 2014 to 2015 might indicate an epidemiological trend that has been already observed in other studies , 29, 30;Our study has several limitations. First, we used an ecological study design, which can give valuable insights in understanding the association between antibiotic use and VRE selection; however, causality cannot be proven. Second, we analyzed aggregated data on ward level and had no data on individual patients. Therefore, controlling for important confounders, such as duration of antibiotic therapy, history of antibiotic exposure or severity of underlying illness was not possible. Since it has been shown that group-level and individual-patient-level analyses might yield different results when the association between antibiotic exposure and resistance is assessed , our resIn conclusion, we found a positive correlation between prior-month use of glycopeptides and current use of carbapenems and the incidence of HA-VRE on ward level when invasive and non-invasive VRE were considered. In addition, detection of at least one patient with CA-VRE in the current month significantly increased the risk of nosocomial acquisition of VRE, thereby indicating the risk of person-to-person transmission of VRE. To this end, a multifaceted approach to lower HA-VRE rates is required including prudent use of antimicrobial agents as well as implementation of and strict compliance to infection control measures to prevent VRE transmission.


Rheum palmatum (Da-Huang). The usage of CM might be an effective complementary method to prevent uterine cervix from progressing to CC after cervical dysplasia has occurred.The Pap test diagnosed cervical dysplasia, which could recover to normal or progress to cervical cancer (CC), is an early stage of cell abnormality before CC. This case-control study analyzed the differences in the risk to develop CC between Chinese medicine (CM) users and nonusers among women who had ever been diagnosed as having cervical dysplasia. A total of 750 CC patients with a cervical dysplasia history were collected between 1998 and 2011 from National Health Insurance Research Database, and controls were women with cervical dysplasia history but did not develop CC. Adjusted odds ratio (aOR) for developing CC was assessed using multivariable logistic regression after adjusting for age, urbanization of residence, and occupation. The proportion of using CM among CC patients was lower than that among CC nonpatients, with an aOR of 0.8. By analyzing the relationship between CC development and the frequency of CM usage, the trend test revealed a significant decreasing trend for developing CC among high-frequency CM users. Moreover, the most frequently used single herb high-frequency was Cervical cancer (CC) is a prevailing cancer in women, with about 528,000 annual cases and 266,000 deaths per year worldwide . The incThe Pap test diagnosed early stage dysplastic cervix, including atypical squamous cells of undetermined significance, low-grade squamous intraepithelial lesion, atypical squamous cells, and high-grade squamous intraepithelial lesion, could either recover to normal or progress to CC. Reported rate of spontaneous regression among cervical dysplasia ranges from 33% to 60%, and the rate of progression to invasive CC ranges from 1% to 12%. Therefore, instead of treatment, close follow-up with repeated Pap tests every three months and colposcopy biopsy are usually suggested for cervical dysplasia . When thChinese medicine (CM) is commonly used as a complementary medicine in the treatment of cancer and has been reported to reduce side effects and reinforce the efficacy of conventional treatment , 10, as As the most important complementary medicine in Taiwan, since 1995 CM have been covered by the National Health Insurance (NHI), which is a health insurance system established by the government . The datThis case-control study used the National Health Insurance Research Database (NHIRD) released by the Bureau of National Health Insurance. Almost all Taiwanese population joins this NHI program, with a coverage ratio of over 99%. NHIRD contained outpatient and inpatient medical claims of each insurant from 1997 to 2011. By reason of the Personal Information Protection Act, the NHIRD was a second-hand database with identity number deidentified. Diseases were defined according to the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) in NHIRD. We collected CC patients (ICD-9-CM 180) with a cervical dysplasia history (ICD-9-CM 622.1) from 1998 to 2011. Patients with CC development within three years after the cervical dysplasia diagnosis were excluded. The index date was defined as the date of CC diagnosis. Approximately twofold randomly selected controls from women with cervical dysplasia but without CC development were frequency-matched with CC patients on age stratum , the year of cervical dysplasia diagnosis, and the year of index date . Patientp value of less than 0.05 was defined to be statistical significant. Chi-square test was used to examine the differences in categorical variables  between CC patients and controls, and the t-test was used to examine the differences in continuous variables. Odds ratio (OR) and 95% confidence intervals (CIs) of CC were assessed using multivariable logistic regression model after adjusting for age, urbanization, and occupation. The association between the development of CC and the frequency of CM usage was estimated by dividing CM users into high-frequency group and low-frequency group. Patients received CM for more than 30 days per year were defined as high-frequency users and the others were defined as low-frequency users. The trend test and multivariable logistic regression model were used to test the association between the frequency of CM usage and CC development.All analyses were performed using SAS software version 9.4 . A two-tailed A total of 750 CC patients and 1498 CC nonpatients who had been diagnosed as cervical dysplasia were extracted from the NHIRD, with the mean age of 56.2 ± 13.2 years . There wCompared to CC nonpatients, there was a lower proportion of CM users among CC patients (19.9% versus 24.0%), with an aOR of 0.80 (95% CI = 0.64–0.99) after controlling for age, urbanization of residence, and occupation . Stratifp = 0.03), compared to CC nonpatients , dominating 2.20% of the total CM single prescription, with a mean daily dose of 0.51 g and a mean yearly prescription of 67.6 days. The second commonly prescribed herb was Salvia miltiorrhiza (Dan-Shen), dominating 1.96% of total CM single prescriptions, with a mean dose of 1.1 g per day and 43.98 days per year. The third most frequently prescribed single was Corydalis yanhusuo (Yan-Hu-Suo), dominating 1.89% of the total CM single prescriptions, with a mean dose of 1.12 g per day and 34.6 days per year. The most commonly prescribed formula was Jia-wei-xiao-yao-san, occupying 4.03% of the total CM formula prescriptions, with a mean dosage of 4.21 g per day and 67.64 days per year. The second frequently prescribed formula was Chuan-qiong-cha-tiao-san, dominating 2.50% of the total CM formula prescriptions, with an average dose of 3.92 g per day and 44.72 days per year. The third frequently prescribed formula was Ge-gen-tang, accounting for 1.74% of the total CM formula prescriptions, with a mean daily dose about 4.12 g per day and 32.35 days per year.The top ten most frequently prescribed CM singles and formulas for CM high-frequency users are listed in It is well known that herbal medicine, including CM, plays an important role in the treatment of cancer. Herbs used in CM have been shown to help in the immune function enhancement and survival rate improvement in cancer patients , 19. In Among cervical dysplasia patients, there were no differences in age and urbanization of residence between who developed CC later and who did not develop CC. Otherwise, there were less proportions of white collar workers, while there were more proportions of blue collar workers and homemakers in patients who developed CC. A higher CC screening participation has been reported among women with qualified occupation than among women who never worked . This imThe logistic regression model revealed that, after being diagnosed with cervical dysplasia, patients who consequently developed CC used less CM than who did not develop CC, with an aOR of 0.8. In most of the stratified subgroups, the aORs for using CM in CC patients ranged from 0.71 to 0.81 compared to CC nonpatients. However, there was no statistical significance in using CM between CC patients and nonpatients in almost all subgroups except in the subgroup aged between 50 and 59. We speculated that the inability to reveal statistical significance was due to the small case number of each subgroup after stratification. On the whole CC patients were less likely to use CM than CC nonpatients after cervical dysplasia had been diagnosed. The result implied that CM might play a role in the prevention of CC from cervical dysplasia. Moreover, the trend test showed that CC patients had a smaller aOR for using CM high-frequently than for using CM low-frequently, implying that the prevention effect might be dose-dependent. As for preventing cancer by CM, a previous population-based study reported that CM might prevent tamoxifen-caused endometrial cancer in breast cancer patients. In that study, among breast cancer patients who take tamoxifen, CM users were less likely to develop endometrial cancer than CM nonusers, with a hazard ratio of 0.61. . Since t Rheum palmatum (Da-Huang) was the most highly used one. Rheum palmatum (Da-Huang), which is used to clear heat and resolve toxin by TCM practitioners, has been shown to possess anti-inflammatory and anticancer ability [ Rheum palmatum (Da-Huang), emodin, was found to inhibit the growth of CC cells by inducing apoptosis through the intrinsic mitochondrial and extrinsic death receptor pathway [ Salvia miltiorrhiza (Dan-Shen), which is used to improve the stasis status, a common condition existing in cancer pathogenesis according the theory of traditional CM [ Salvia miltiorrhiza (Dan-Shen) has also been found to possess anti-inflammatory and anticancer activities in several cancer cell lines, not only via inducing apoptosis of cancer cell but also via inhibiting the estrogen receptor signal pathway, indicating it might influence the stimulation of estrogen on CC cells [ Corydalis yanhusuo (Yan-Hu-Suo), which is also used traditionally to remove stasis and has been found to be with an antiproliferative effect in cancer cells through the combined actions of its two main compounds, named tetrahydropalmatine and berberine [ Scutellaria baicalensis (Huang-Qin), from which baicalein is isolated and has been reported to have the function of suspending the cell cycle and inhibiting the proliferation of SiHa and HeLa cervical cancer cells [ Zizyphi spinosi semen (Suan-Zao-Ren), which is widely used for the treatment of insomnia. Its active compound, Sanjoinine A, has been shown to increase sleep rate and sleep time [ Zizyphi spinosi semen (Suan-Zao-Ren) might help in the prevention of cancer through its sedative effect.Among the top ten CM single herbs used by the high-frequency CM users, ability . Moreove pathway . The secional CM , 24. SalCC cells . The thierberine . The fouer cells . The fifeep time . It has eep time ; therefo Ligusticum chuanxiong (Chuan-qiong). With its antioxidative function, Ligusticum chuanxiong (Chuan-qiong) possesses anticancer effects through the induction of apoptosis and inhibition of DNA damage [ Puerariae radix (Ge-gen). The main component of Puerariae radix (Ge-gen), puerarin, has been reported to decrease the activities of tumor by inhibiting tumor growth [ Zizyphi spinosi semen (Suan-Zao-Ren), which was the fifth frequently prescribed single herb in this study. Therefore, Suan-zao-ren-tang and Tian-wang-bu-xin-dan might prevent cancer via a similar mechanism to Zizyphi spinosi semen (Suan-Zao-Ren). By analyzing the top five CM singles and formulas used by high-frequency CM users, we hypothesized that besides herbs that are pharmacologically proved to possess anticancer activities, herbs that are used to treat mental symptoms are also important in the prevention of cervical cancer. This hypothesis could be supported by the theory that unstable mental status could cause immune dysfunction [The top one CM formula used by CM users in the present study was Jia-wei-xiao-yao-san, which has been reported to improve the survival in a variety of cancer patients . MoreoveA damage . The thir growth  and indur growth . The foufunction . Moreovefunction . We specThe basic limitation of the present study was the retrospective design, which could only reveal a correlative association between CC and CM usage, but it cannot show a causal relationship between these two variables. The second limitation is that the NHI database is a collection of insurance reimbursement data, instead of being designed for research. Therefore, there might be incorrect data and missing data in the database. Third, the database only records medical prescription, instead of real medicine taking, so there may be biases in counting dosage. Fourth, since the national insurance system did not pay other forms of complementary medicine, such as Ayurveda, hypnosis, aroma, and homeopathy, we could not adjust for variables of other types of complementary medicine. And fifth, although models in this study have been adjusted for age, urbanization, and occupation, these confounding factors might still affect the efficacy of CM. Besides, confounding factors mentioned in the second, third, and fourth limitations could not been put into model for adjusting; therefore, there might be bias in this study. On the other hand, the advantage of this study design is that a large number of subjects containing the whole population were recruited at the same time. The present study provided evidence for the fact that the use of CM negatively correlated with CC development and found possible CM candidates which might be beneficial to cervical dysplasia patients.In conclusion, this case-control retrospective study showed that, after the dysplasia had been diagnosed, patients might have less opportunity to progress to CC if they take CM. Moreover, high-frequency CM users gained even lower risk of CC than low-frequency users. This study suggested that the usage of CM might be a complementary method to prevent the development of CC from cervical dysplasia.


Hepatocellular carcinoma (HCC) is the leading cause of cancer mortality. Chemical and virus induction are two major risk factors, however, the potential molecular mechanisms of their differences remain elusive. In this study, to identify the similarities and differences between chemical and virus induced HCC models, we compared the gene expression profiles between DEN and HBx mice models, as well as the differences among tumor, para-tumor and normal tissues.We sequenced both gene and microRNA (miRNA) expression for HCC tumor tissues, para-tumor and normal liver tissues from DEN model mice (30-week-old) and downloaded the corresponding microarray expression data of HBx model from GEO database. Then differentially expressed genes (DEGs), miRNAs and transcription factors (TFs) were detected by R packages and performed functional enrichment analysis. To explore the gene regulatory network in HCC models, miRNA and TF regulatory networks were constructed by target prediction.For model comparison, although DEGs between tumor and normal tissues in DEN and HBx models only had a small part of overlapping, they shared common pathways including lipid metabolism, oxidation-reduction process and immune process. For tissue comparisons in each model, genes in oxidation-reduction process were down-regulated in tumor tissues and genes in inflammatory response showed the highest expression level in para-tumor tissues. Genes highly expressed in both tumor and para-tumor tissues in two models mainly participated in immune and inflammatory response. Genes expressed in HBx model were also involved in cell proliferation and cell migration etc. Network analysis revealed that several miRNAs such as miR-381-3p, miR-142a-3p, miR-214-3p and TFs such as Egr1, Atf3 and Klf4 were the core regulators in HCC.Through the comparative analyses, we found that para-tumor tissue is a highly inflammatory tissue while the tumor tissue is specific with both inflammatory and cancer signaling pathways. The DEN and HBx mice models have different gene expression pattern but shared pathways. This work will help to elucidate the molecular mechanisms underlying different HCC models.The online version of this article (doi: 10.1186/s12885-017-3860-x) contains supplementary material, which is available to authorized users. Hepatocellular carcinoma (HCC) accounts for 85 - 90% of liver malignancies and is the second cause of cancer death in the world . AlthougDiethylnitrosamine (DEN), a DNA alkylating agent, is widely used to induce liver cancer in rodent model with high success rate and similarity to human HCC . RecentlIn recent years, microRNAs (miRNAs) and transcription factors (TFs) have drawn extensive attention in cancer research. They play pivotal roles in proliferation, differentiation, invasion and metastasis of tumors. Many miRNAs were reported as important regulators in HCC. For example, miR-221 promotes human HCC development and its silencing contributes to suppressing tumor properties . MiR-214In this study, we applied bioinformatic approaches to analyze the high-throughput and microarray data of DEN and HBx HCC mice models. We aim to analyze the gene expression features and core regulatory factors in HCC from these two models, and reveal the similarities and differences between them as well as compare gene expression profiles in tumor, para-tumor and normal tissues in each model.All of the experimental mice were male and purchased from Hubei Research Center of Laboratory Animals  and in the C57 genetic background. To induce HCC in mice, we used DEN as the inductive agent. In this study, all mice were divided into two groups: DEN group and control group. In DEN group, mice were fed with basal diet every day and given DEN treatment at a dose of 165 mg per kg body weight in sesame oil through oral once a week for 10 weeks, then drug treatment were stopped and the mice were fed with diet only until 30 weeks. In control group, mice were fed with basal diet only until 30 weeks. In order to determine whether the liver tissues have suffered cancerous changes, histopathologic examinations were conducted via microscope .http://www.ncbi.nlm.nih.gov/geo/, GEO accession: GSE15251). This model used Hepatitis B virus X antigen (HBx) to induce HCC in transgenic male C57 mice. The microarray samples of tumor, para-tumor and normal tissues were from the 16-month-old mice and the experimental conditions were similar with our DEN model.The microarray expression data of HBx model were downloaded from Gene Expression Omnibus (GEO)  was used for mapping sequencing reads to mouse genome GRCm38, and StringTie (version: 1.2.2) was used to assemble the RNA-seq alignments into potential transcripts based on the reference sequences and calculate the abundance of transcripts . The expx(x) = P(X ≤ x), where the right-hand side represents the probability that the random variable X takes on a value less than or equal to x [https://david.ncifcrf.gov/tools.jsp) for GO (gene ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis. The top ranked enrichment results with high significant levels  were selected for discussion and presented by bubble plots using R package ‘ggplot2’. In the bubble plot, rich factor is calculated as the ratio of gene counts that mapped to a certain pathway and the total gene number of that pathway.The expression characteristics of two models were displayed by cumulative distribution function plot. The definition of cumulative distribution function is: Fual to x . And theTo reveal the gene expression difference between tumor and non-tumor tissues in two models, the pairwise comparisons of DEGs were carried out among tumor, para-tumor and normal tissue. Venn diagrams of DEGs were drawn and pathway enrichment in each model were implemented as described above.To further compare similarities and differences between two models, we firstly analyzed the similarities and differences between tumor tissue in DEN model and HBx model, and then focused on the para-tumor tissues of two models. The common pathways in two models were shown by bar charts, and the different pathways were exhibit by bubble plots. What’s more, heatmaps were used to recognize the gene expression patterns among three tissues.Networks were constructed using the differentially expressed data by reference to the collected validated data from several databases. For miRNA, we collected experimentally verified targets as described in our previous review paper . The datIn this study, a total of 20,901 genes were detected by high-throughput sequencing in DEN model, and 23,855 genes were identified in HBx model microarray data. To investigate the relationship between the increasing ratio of gene numbers and the gene expression level, the cumulative distributions of genes in two models are shown in Fig. To investigate the functions of the key genes in two models, the comparison of top 5% highly expressed genes of the corresponding tissues in two models were carried out Fig. . The twoTo compare the gene expression between tumor and non-tumor tissues in two models, the pairwise comparisons of DEGs were performed among tumor, para-tumor and normal tissues. The statistical results of up- and down-regulated genes in each model were shown in Fig. To further investigate gene expression differences among three tissues in two models, we recognized the gene expression patterns and found 6 clusters in each model Fig. . Genes wFrom the above results, we could summarize that the healthy liver tissue is mainly characterized with lipid biosynthetic and metabolic process and oxidation-reduction on account of maintenance the normal life activities, while the tumor tissue is characterized with immune, inflammatory response and cancer pathways. The immune effect and inflammatory response in para-tumor tissue are higher than normal tissue. What’s more, these responses also show a slight declined trend in tumor tissue when compared with para-tumor tissues. Therefore, we suggest that the para-tumor tissue should be regarded as inflammatory tissue rather than normal tissue.To disclose the similarities and differences of gene functions between two models, we further focused on tumor tissues and para-tumor tissues in two models. The DEGs of tumor vs normal tissue and para-tumor vs normal tissue were regarded as the specific genes of tumor tissue and para-tumor tissue, respectively. As a result, we found the DEN and HBx models only shared a small part of tumor specific genes Fig. . FurtherTo explore the miRNA expression and their regulation to genes in HCC, we sequenced the miRNA in the DEN model. We totally obtained 28 differentially and highly expressed miRNAs Fig.  from theTo recognize the molecular regulation mechanism in HCC, a miRNA-gene regulation network was constructed in DEN model. Firstly, we found out a total of 186 genes that show opposite expression tendency with miRNAs. Then regulatory relationships between the miRNAs and genes were screened out according to verified miRNA targets which collected from several databases. Finally 98 regulatory pairs were obtained and intergrated into a network containing 17 miRNAs and 50 genes with 98 edges Fig. . In thisFor the HBx model, although we have no corresponding miRNA data, we can identify the differnetially expressed TFs and explore the TF regulatory network. From the DEGs we obtained 15 highly expressed TFs Fig. . The regTo investigate the synergistic regulations on oncogenes and tumor suppressor genes (TSGs) of TFs, we collected the oncogenes and TSGs in HCC from previous publications , 37. We In this study, we investigated the highly expressed genes in both DEN and HBx mice models, and identified the DEGs through comparison among tumor, para-tumor and normal tissues. The gene expression profiles and function enrichment of different tissues demonstrate different characteristics and functional specificities of three tissues. Moreover, through comparison of two models, we found both similarities and differences exited in gene expression. Finally, we constructed miRNA and TF regulatory networks and identified several key regulators from the networks, as well as revealed some synergistic regulations in HCC models.Through comparison of tumor, para-tumor and normal tissues, we suggest that para-tumor liver tissues should be regarded as inflammatory tissue rather than normal tissue. But in the study of human solid carcinomas, due to the sampling limitations, researchers usually use comparison of tumor and adjacent non-tumor tissues of patients to illustrate the molecular mechanism of cancers. In fact, from our study, the maximal effects of immune responses and inflammatory responses were detected in para-tumor tissues rather than tumor tissues or normal tissues. While the normal tissues were characterized with lipid mechanism and oxidation-reduction, and the tumor tissues enriched in cancer signal transduction, immune and inflammatory responses Figs.  and 3. TIn previous studies, both DEN- and HBx-induced mice liver cancer models have been used to investigate the pathogenesis of HCC, they have become the two major concerns in liver cancer research , 10, 13.TGFbeta signaling pathway and was found to prevent the formation of hepatocellular carcinomas and cholangiocarcinoma development [At the same time, we also identified differentially expressed miRNAs and TFs from the data, and constructed two major regulatory networks. From network analysis, miR-381-3p, miR-142a-3p, miR-214-3p and Egr1, Atf3, Klf4 were identified to be the most important regulators in HCC. These are important tumor suppressors which can be considered as diagnosis biomarkers and treatment targets. What’s more, the synergistic regulation analysis indicated that Cdkn1a is the most import target gene of multiple TFs in HCC Fig. . It can elopment . Taken tThrough gene expression and function analyses, we found that both DEN and HBx model shared common pathways including lipid metabolism, oxidation-reduction process, immune process and inflammatory responses. Through tissue comparison, we suggest that the para-tumor should be recognized as inflammatory tissue. Network analysis revealed that miRNAs such as miR-381-3p, miR-142a-3p, miR-214-3p and TFs such as Egr1, Atf3 and Klf4 are the hub regulators in HCC. These results will help to increase understanding of molecular mechanisms of HCC.Additional file 1: Figure S1.Figure S2. Different pathways in the same tissue in two models. a Tumor tissues. b Para-tumor tissues. The terms on vertical axis beginning with ‘DEN’ or ‘HBx’ represent the enrichment terms of genes in DEN model or HBx model. Figure S3. Quantification of the proteins of two genes, DROSHA and ADAR. (a) Pictures of immunohistochemistry results. (b) Gene expression levels (FPKM) and protein expression levels  of these two genes. Figure S4. The subnetworks of the TFs Egr1, Atf3 and Klf4. Gold diamond: TFs. Purple oval: genes. (DOCX 7118 kb)Histopathologic examinations of liver tissues under microscope. All the pictures were captured at magnification of 100×. The first two lines are tissue slices of control and DEN treatments at different time point in DEN model. The third line indicates that the Kupffer cells increased over time. Kupffer cell is a kind of specialized macrophage which plays a major anti-inflamination role in liver, its increasing can reflect the injury level of liver. In this study, the injury significantly increased as time goes on. The pictures in the last line show histological changes from control to para-tumor and tumor tissues of liver at the 30th week. Additional file 2:Gene enrichment analysis of top 5% highly expressed genes of tumor tissue in DEN model and HBx model. (XLSX 57 kb)


Stress is a common experience in today’s society. Smartphone ownership is widespread, and smartphones can be used to monitor health and well-being. Smartphone-based self-assessment of stress can be done in naturalistic settings and may potentially reflect real-time stress level.The objectives of this systematic review were to evaluate (1) the use of smartphones to measure self-assessed stress in healthy adult individuals, (2) the validity of smartphone-based self-assessed stress compared with validated stress scales, and (3) the association between smartphone-based self-assessed stress and smartphone generated objective data.A systematic review of the scientific literature was reported and conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. The scientific databases PubMed, PsycINFO, Embase, IEEE, and ACM were searched and supplemented by a hand search of reference lists. The databases were searched for original studies involving healthy individuals older than 18 years, measuring self-assessed stress using smartphones.r=.4; P<.05); and (3) in exploratory analyses, smartphone-based self-assessed stress was found to correlate with some of the reported smartphone generated objective data, including voice features and data on activity and phone usage.A total of 35 published articles comprising 1464 individuals were included for review. According to the objectives, (1) study designs were heterogeneous, and smartphone-based self-assessed stress was measured using various methods ; (2) the validity of smartphone-based self-assessed stress compared with validated stress scales was investigated in 3 studies, and of these, only 1 study found a moderate statistically significant positive correlation (Smartphones are being used to measure self-assessed stress in different contexts. The evidence of the validity of smartphone-based self-assessed stress is limited and should be investigated further. Smartphone generated objective data can potentially be used to monitor, predict, and reduce stress levels. Many people experience stress, in one form or another, throughout their lives. Stress can be defined as “a state, which is accompanied by physical, psychological or social complaints or dysfunctions and which results from individuals feeling unable to bridge a gap with the requirements or expectations placed on them” . OverallPeople suffering from chronic stress may be less likely to notice whether they are under high stress at a given time point. Using self-assessment of stress during a time period could potentially increase awareness of stressors and encourage behavioral changes.In 2015, there were 3.4 billion smartphone subscriptions in the world , and it Subjective self-assessed stress can be measured using smartphones via ecological momentary assessment (EMA). EMA is a collection of methods used to collect “assessments of subjects’ current or recent states, sampled repeatedly over time, in their natural environment” . AdvantaMany people carry their smartphones with them throughout the day and are used to interacting with it in many locations, in many situations, and at all times . Thus, sHowever, with no systematic review within this area, the extent to which smartphone-based self-assessed stress has been monitored and evaluated in healthy individuals is unknown. Furthermore, the validity of smartphone-based self-assessed stress compared with other validated stress scales has not been evaluated systematically. Thus, the objectives of this systematic review were to evaluate (1) the use of smartphones to measure self-assessed stress in healthy adult individuals, (2) the validity of smartphone-based self-assessed stress compared with validated stress scales, and (3) the association between smartphone-based self-assessed stress and smartphone generated objective data.This was the first systematic review of smartphone-based self-assessed stress in healthy adult individuals.This systematic review was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement . MethodsOriginal studies involving healthy individuals older than 18 years measuring self-assessed stress on a smartphone were eligible for review. The language of publication was restricted to English. Papers not meeting eligibility criteria or only describing the technical part of the self-assessment of stress were excluded from review. Where multiple articles were reported on the same study, the article presenting the largest and most detailed dataset was included for review. Only studies in which self-assessed stress was reported on smartphones were eligible for review.Published studies were identified by conducting a systematic literature search through the electronic databases PubMed, PsycINFO, Embase, IEEE, and ACM. The literature search was supplemented by a hand search of reference lists of retrieved articles. The literature search was conducted by 1 researcher (HP), without time restrictions, using the following keywords:  AND  and covered a period from 1980 to May 2016. The last literature search was conducted on May 4, 2016.A PRISMA flow diagram of the study selection process is presented in The literature search identified a total of 1517 articles from the 5 databases, and 11 additional studies were identified by hand search of reference lists. Removing duplicates left 1307 articles for further evaluation. Reviewing abstracts and titles resulted in the exclusion of a total of 1118 articles for not meeting eligibility criteria, the 2 main reasons for exclusion being not including human subjects and not involving stress. Thus, 189 full-text articles were evaluated for eligibility. Of these, 154 articles were excluded from the review for various reasons , with thOf the 35 studies, 17 were from the United States and the remainder were from Finland (n=3), Italy (n=4), Germany (n=2), Switzerland (n=2), the United Kingdom (n=3), Australia (n=1), Hong Kong (n=1), Portugal (n=1), and Sweden (n=1). The majority of studies were prospective observational studies -45,49-58Overall, the studies comprised a total of 1464 healthy adult participants, with sample sizes in individual studies varying from 1 to 198 participants. The mean age of the participants was available for 19 of the studies and ranged from 20.1-52.47 years -52,55,57The majority of the studies used Android-based smartphones (n=19), 3 used Windows-based smartphones ,34,41, 3Overall, the included studies used many different methods to measure smartphone-based self-assessed stress. The most common method (n=11) was using a Likert scale  ,54-56,58. In most of the studies, participants were asked to report their stress levels multiple times per day: from twice a day [The frequency of smartphone-based self-assessed stress reports varied ce a day ,49,50 toce a day . In 1 stce a day , whereasce a day ,41,46. Ice a day ,32,35,36Six studies investigated self-assessed stress in the context of the workplace ,38,42,58In 5 studies, validated stress scales in addition to smartphone-based self-assessed stress were reported. Four of these studies used the Perceived Stress Scale (PSS) ,50,53,59r=.562, P=.11) between smartphone-based self-assessed stress levels and PSS score [P=.64) between smartphone-based self-assessed stress and DSP score [r=.458, P=.003) and poststudy  [Three studies investigated the correlation between smartphone-based self-assessed stress and validated stress scales ,46,53. ASS score . Anotherr=.59, P value not specified) between smartphone-based self-assessed stress and voice-stress, whereas Ferdous et al reported a significant positive correlation between smartphone-based self-assessed stress and duration of verbal interaction for 17 of their 28 participants .A total of 13 studies collected smartphone generated objective data ,42,48-53A study by Madan et al reported that communication diversity was reduced for participants who often assessed themselves as being stressed, and the authors interpreted this as a tendency to isolate . A studyTwo studies investigated the association between self-assessed stress and smartphone generated objective data in order to detect stress ,31. A stThis was the first systematic review on smartphone-based self-assessment of stress in healthy adult individuals. A total of 35 published articles involving a total of 1464 participants were included for review. Overall, the study designs were highly heterogeneous, using various methods of self-assessment in different contexts. Most of the studies were conducted in the United States or Western Europe. Android-based smartphones were most commonly used for measuring self-assessed stress, many participants borrowed smartphones during the studies, and often stress was reported multiple times per day.Regarding the validity of smartphone-based self-assessed stress levels, stress levels measured using validated stress scales were available in 5 studies, but only 3 of these studies investigated the correlation between smartphone-based self-assessed stress and validated stress scales. Among these 3 studies, only 1 study found a statistically significant positive correlation between self-assessed stress and a validated stress scale (PSS) . It shouSmartphone generated objective data were collected in 13 studies and 6 studies investigated the association between smartphone-based self-assessed stress and these objective data. Two studies found a positive correlation between self-assessed stress and verbal data, whereas another 2 studies found associations between self-assessed stress and communication diversity, activity levels, text messages, and screen on or off patterns. The last 2 studies found smartphone generated data to be a predictor (accuracy up to 72.28%) for detecting self-assessed stress. Overall, regarding smartphone generated objective data, the studies collected various smartphone generated data and the results seem exploratory, with a tendency to report statistically significant positive correlations with self-assessed stress only.A majority of the included studies collected objective data alongside the self-assessed data. Some of them used physiological measures collected from various worn sensors, but others only used objective data collected from sensors embedded within the smartphones. Seven studies collected all 3 kinds of stress measures. Collecting physiological measures such as heart rate requires participants to carry additional sensors (user burden), whereas smartphone generated objective data are collected from a smartphone that is most likely already being carried around. Smartphone generated objective data can usually be collected automatically, eliminating attrition due to monitoring. Objective smartphone data are behavioral data that can reflect behavior related to stress. Different people react differently to stress, and combined with self-assessed data on stress, smartphone generated objective data might be used for detecting stress. Early stress detection in healthy populations such as students and employees could help to prevent stress-related diseases. Thus, the use of smartphone generated objective data as a marker of stress in healthy individuals has been sparingly investigated and future well-designed studies investigating this would be interesting.Stress levels were assessed from self-reported data, both from smartphones and from validated scales. PSS was developed in 1983. It has 10 questions and is widely used within psychological and psychiatric sciences. It has shown good internal reliability  and is Registering self-assessed stress multiple times a day can be a tool to help people self-monitor stress levels. In this way, self-monitoring may play a role in helping people to manage stress. Self-monitoring brings awareness of stress levels and encourages behavioral change according to a situation . HoweverA study by Wang et al looked at stress in students over a whole semester and revealed how their self-assessed stress level increased as their workload increased, with the peak being during final examinations . FollowiMost studies measured self-assessed stress on Android-based smartphones, and many participants were provided with smartphones during the study period. Allowing participants to use their own smartphones to collect self-assessment of stress would be the least disruptive for participants, as they are already familiar with the device. Using one’s own smartphone would also be likely to more accurately reflect real life, especially in regards to the objective smartphone data. It is possible that participants did not, in all cases, own smartphones. It is also possible that the study smartphones were specially programmed for the study or that participants’ smartphones were different from the ones that were required for the study.Smartphones constitute a new and an exciting research tool within psychological well-being and health care. Nevertheless, the majority of the identified studies have been published in proceedings from technological conferences. In general, many of these studies focused primarily on the technical side of the smartphone system, and a number of these did not present data on population characteristics such as age ,53,54,58Limitations at a study level: Several concerns regarding the individual studies and outcomes limited the overall findings of this study. The included studies had highly heterogeneous designs and used various methods to measure smartphone-based self-assessed stress. In addition, in many cases studies did not include clear descriptions of the recruitment process. The studies included were at risk of selection bias, and at an individual study level, there was a lack of information on potential confounding factors such as age, gender, and educational level, which possibly could have affected self-assessed stress level. A large part of the studies included a relatively small sample of participants and reported unadjusted statistical analyses. Validated stress scales were only used in 5 studies out of the 35 studies included. More than half of the included studies did not investigate stress as their primary objective, and information was therefore limited: only 1 out of the 4 largest studies had stress as their primary objective. In general, studies focusing on stress had fewer participants (mean n=24.7) compared with the studies not focusing on stress (mean n=56.3). Self-assessed stress was investigated in selected groups, often recruited through convenience sampling at a university or a workplace. In many of the studies, participants were provided with a smartphone to use during the study period, and some participants received economic incentives to fill out the self-assessments of stress. The generalizability of these studies was therefore limited, but findings could be relevant for more narrow populations such as university students. Overall, methodological limitations related to study designs, self-assessments of stress, as well as statistical analyses of the included studies were observed. There is a need for studies investigating the use and validity of smartphone-based self-assessed stress in more general populations.Limitations at a review level: Some limitations to this review should be mentioned. Research using smartphones is expanding, and due to the intersectionality of this research , studies are being published in very diverse forms and places. Our review shows that many of these kinds of studies are being published in conference proceedings. Therefore, conducting a search strategy that is able to capture all relevant scientific articles is a challenge. The review process was restricting among healthy smartphone users and articles published in English, which might have reduced the global acceptance.Stress has become a major health problem in the Western world. Awareness of one’s own stress level is important, and smartphones are potentially a proper minimally intrusive tool for self-assessment of stress.Self-assessment of stress using smartphones in everyday life is a step toward stress awareness. Looking at self-reported stress levels in relation to other more objective data from smartphones, such as geolocation and physical activity, could help to further understanding of stress and stress-related behavior. However, well-designed studies using strict methodology investigating the validity of smartphone-based self-assessment of stress are warranted. Future studies should investigate how to validly measure subjective stress using smartphones, which by nature is accurate in time and place, in contrast to a self-reported scale on stress administered once a day or less frequently. They should also collect information on and address possible confounding factors in the statistical analyses. In addition, and of even more paramount importance, they should investigate in a randomized controlled trial whether the use of smartphone to monitor stress—subjectively or objectively assessed—per se has a beneficial or detrimental effect on stress level.This review included only studies with healthy adult participants. Smartphones can and are also being used to measure self-assessed stress in various patient populations, especially within the mental health field, where stress is a risk factor. However, addressing this aspect was beyond the scope of this review.This systematic review identified 35 studies using smartphones to measure self-assessed stress in healthy adults. The studies were from different countries and used different self-assessment methods in varying contexts, such as in the workplace, in relation to smoking cessation, and on university campuses. Android-based smartphones were most commonly being used, and the validity of smartphone-based self-assessed stress compared with validated stress scales was limited by low statistical power of the individual studies and small number of studies reporting on validated scales. Some smartphone generated objective data, including voice, activity, and general usage data, were associated with self-assessed stress measured on smartphones. Smartphone generated objective data could represent a potential tool for predicting stress levels. There is a need for further studies investigating the validity of smartphone-based self-assessed stress and smartphone generated objective measures of stress using validated stress scales, and studies investigating the beneficial or detrimental effects of smartphone-based monitoring stress, both subjectively and objectively, on stress levels per se.


We report the latest innovations in their management, in particular the results of three trials concerning the use of the mammalian target of rapamycin (mTOR) inhibitor, everolimus, in non-functional NETs of lung/ gastrointestinal (GI) origin, the first randomised trial of radiolabelled  This is particularly important for patients with lung carcinoids, as there is currently no approved treatment for such patients.The trial included 302 patients in which the patients were randomised (2:1) to everolimus (10 mg/d) or placebo and were stratified by tumour origin, World Health Organization performance status and prior SSA treatment. There was a statistically significant 52% reduction in the relative risk of progression or death in favour of everolimus, with a clinically relevant 7.1-month prolongation of progression-free survival (PFS) compared with those who had taken placebo. In addition, everolimus was well tolerated and its established safety profile confirmed.Previous studies have demonstrated the efficacy of everolimus, an inhibitor of mammalian target of rapamycin (mTOR) 15 Over the past 15 years, PRRT with the radiolabelled somatostatin receptor agonists, such as 90Y-DOTATOC, 177Lu-DOTATATE and 177Lu-DOTATOC, have been successfully used to target metastatic and inoperable NETs.16 Now, Strosberg and colleagues have presented data from the NETTER-1 trial,17 a phase III multicentre, stratified, open, randomised, controlled trial evaluating the efficacy of 177Lu-DOTA0-Tyr3-Octreotate  in patients with inoperable, somatostatin receptor-positive mid-gut NETs progressing on LAR (20–30 mg every 3–4 weeks). The trial recruited 230 patients from 35 sites in eight European countries and 15 centres in the US, with grade 1–2 mid-gut NETs. Patients were randomised to receive either four administrations of Lutathera (7.4 GBq every 8 weeks) plus their octreotide LAR or ‘high-dose’ octreotide LAR (60 mg every 4 weeks). PFS was evaluated via Response Evaluation Criteria In Solid Tumors (RECIST) criteria every 12 weeks. The median PFS was not reached for Lutathera (in more than 25 months of treatment) but was 8.4 months for the high-dose octreotide LAR group (p<0.0001), with the number of disease progressions/deaths 23 in the Lutathera group and 67 in the Octreotide LAR group. The estimated PFS in the Lutathera arm was 40 months. This phase III trial showed a statistically significant increase in PFS in patients with advanced mid-gut NETs treated with Lutathera providing a valid therapeutic option with minimal adverse events.Over many years, peptide receptor radionuclide therapy (PRRT) using radiolabelled octreotide has been extensively used for the treatment of progressive NETs, and while individual results have been encouraging, there has been no formal assessment of such therapy. For most NETs, molecular-targeted radiation therapy involves the systemic administration of a radiolabelled peptide designed to target somatostatin receptors on tumour cells with high affinity and specificity.18 In current practice, patients with CS are generally treated with long-acting SSAs which have an inhibitory effect on tumour secretion of serotonin and other neuropeptides into the systemic circulation. Many patients respond to SSAs initially, but some are refractory, while in others the response may be lost over time. In 2014 Kulke and coworkers published the results of a preliminary study to assess the safety of an orally active 5-HT synthesis inhibitor, telotristat etiprate (TE), compared with placebo in 23 patients with CS-related diarrhoea inadequately controlled by octreotide.19 TE acts by inhibiting tryptophan hydroxylase, the rate-limiting enzyme in the conversion of tryptophan to serotonin in NETs. Their preliminary results showed a proof-of-concept supporting the clinical benefit of TE across several endpoints, including decreased frequency of bowel movements (BM), decreased urinary 5-hydroxyindoleacetic acid (5-HIAA) levels and patient-reported relief of symptoms.19 A prospective, exploratory, dose-escalating 12-week, open-label, multicentre study of TE on 15 patients with metastatic, well-differentiated, NETs and CS showed improvement in CS with a 74% reduction in urinary 5-HIAA and a 43.5 % reduction in BM.20Finally, a significant problem in patients with mid-gut carcinoids is the carcinoid syndrome (CS) of principally diarrhoea and flushing. The symptoms of CS have been attributed, in part, to elevated levels of 5-hydroxytryptamine (5-HT) (serotonin) secreted by the tumour.21 a pivotal phase III global clinical trial evaluating the efficacy of TE in treating patients with CS inadequately controlled by SSA therapy. This trial included 135 patients with metastatic NETs and inadequately controlled CS (≥4 daily BMs on SSA therapy) who were randomly assigned to receive TE (250 or 500 mg) or placebo while continuing SSA over a 12-week double-blind period. The primary objective was met, with at least a 30 % reduction in BM frequency for ≥50 % of the time on study in 20 %, 44 % and 42 % on placebo, TE 250 mg three times daily (tid) and TE 500 mg tid, respectively (p≤0.040 for both TE doses versus placebo). Secondary objectives including changes in urinary 5-HIAA, cutaneous flushing episodes and abdominal pain were met for both dosage regimes, but reductions in flushing and abdominal pain were not statistically significant. Thus, TE appears to be a new approach to the treatment of the CS, which is generally safe and well tolerated, and represents a promising new class of therapy for patients who have metastatic NETs with CS not controlled by SSAs.At the ECC meeting, Kulke and colleagues presented the results of TELESTAR,Lutathera will soon become commercially available. However, the sequencing of such treatments, and the costs of their administration, remain problematic matters. Finally, it will be very useful to have TE added to our armamentarium of agents for CS-associated symptoms; while its therapeutic efficacy is perhaps not as major as one might have anticipated, the possible effects on avoiding or minimising mesenteric fibrosis and cardiac valvular dysfunction remains an exciting possible innovation.22How do these new studies alter our approach to patients with NETs? It would seem that everolimus can retard the progression of all NETs regardless of their origin or functional status, although the tumours are generally stabilised rather than shrunk, and it is unclear as to when this therapy should be initiated and how robust is its long-term efficacy. For PRRT, we have long considered this may be of value: it is now reassuring to see this confirmed in a formal study, and it is hoped that CLARINET – Study of Lanreotide Autogel in Non-functioning Entero-pancreatic Endocrine TumoursNETTER-1 – A Study Comparing Treatment With 177Lu-DOTA0-Tyr3-Octreotate to Octreotide LAR in Patients With Inoperable, Progressive, Somatostatin Receptor Positive Midgut Carcinoid TumoursPROMID – Placebo Controlled, Double Blind, Prospective, Randomized Study on the Effect of Octreotide LAR in the Control of Tumor Growth in Patients with Metastatic Neuroendocrine Midgut TumorsRADIANT-2 – Everolimus and Octreotide in Patients With Advanced Carcinoid TumorRADIANT-3 – Efficacy and Safety of Everolimus (RAD001) Compared to Placebo in Patients With Advanced Pancreatic Neuroendocrine TumorsRADIANT-4 – Everolimus Plus Best Supportive Care vs Placebo Plus Best Supportive Care in the Treatment of Patients With Advanced Neuroendocrine Tumors (GI or Lung Origin)TELESTAR – Telotristat Etiprate for Somatostatin Analogue Not Adequately Controlled Carcinoid Syndrome