Analysis of cyclic nucleotide binding (CNB) domains shows that they have evolved to sense a wide variety of second messenger signals; a mechanism for allosteric regulation by CNB domains is proposed. The cyclic nucleotide binding (CNB) domain regulates signaling pathways in both eukaryotes and prokaryotes. In this study, we analyze the evolutionary information embedded in genomic sequences to explore the diversity of signaling through the CNB domain and also how the CNB domain elicits a cellular response upon binding to cAMP.Identification and classification of CNB domains in Global Ocean Sampling and other protein sequences reveals that they typically are fused to a wide variety of functional domains. CNB domains have undergone major sequence variation during evolution. In particular, the sequence motif that anchors the cAMP phosphate (termed the PBC motif) is strikingly different in some families. This variation may contribute to ligand specificity inasmuch as members of the prokaryotic cooA family, for example, harbor a CNB domain that contains a non-canonical PBC motif and that binds a heme ligand in the cAMP binding pocket. Statistical comparison of the functional constraints imposed on the canonical and non-canonical PBC containing sequences reveals that a key arginine, which coordinates with the cAMP phosphate, has co-evolved with a glycine in a distal β2-β3 loop that allosterically couples cAMP binding to distal regulatory sites.Our analysis suggests that CNB domains have evolved as a scaffold to sense a wide variety of second messenger signals. Based on sequence, structural and biochemical data, we propose a mechanism for allosteric regulation by CNB domains. The cyclic nucleotide binding (CNB) domain is a conserved signaling module that has evolved to respond to second messenger signals such as cAMP and cGMP ,2. The CCNB domains also occur in prokaryotes. The first characterized family containing a CNB domain in prokaryotes is the CAP (catabolite gene activator protein) family of transcriptional regulators  that conCrystal structures of CNB domains from both eukaryotes and prokaryotes have been determined and their structural comparison reveals a conserved mode of cAMP recognition  and reguAn emerging theme in CNB domain signaling is the allosteric control of CNB domain functions. In the PKA regulatory subunit, for instance, cAMP binding to the beta subdomain causes conformational changes in the distal alpha subdomain, thereby releasing its inhibitory interactions with the catalytic subunit . This prIn the following sections, we first describe the identification and classification of CNB domains to illustrate the diversity of this protein family, and later show how a comparative analysis of CNB domain sequences has provided insights into the evolution of allostery.Cyclic nucleotide binding domains in the National Center for Biotechnology Information's non-redundant amino acid database (NR) and Global Ocean Sampling (GOS) ,20 data Archaeoglobus fulgidus. CNB domains in eukaryotes can be broadly classified into five major categories: the kinase domain associated PKA and PKG families; the guaninine nucleotide exchange factor (Epac's); transmembrane domain containing HCN and Na channels; HCN type channels in protozoans; and CNB domains in metazoans and plants that are fused to functional domains such as PAS domains, PP2C like phosphatases and phospholipases  that contain a DNA binding domain covalently linked to the CNB domain; and a distinct class of DNA binding domain containing proteins  that are activated by second messenger signals such as NO, oxygen and heme . In addilac operon [Most of the GOS sequences, as expected, are prokaryotic in origin since they belong to families that are exclusively prokaryotic Table . In partc operon . In addic operon , is alsoThermotoga maritime has been determined as part of the structural genomics initiative [Until now, the primary function of CNB domains in prokaryotes was believed to be in the transcriptional regulation of genes. However, our analysis suggests that other cellular processes, such as ATP production, protein phosphorylation and NADH production, may also involve CNB domain functions Table . Of partitiative . The occOther novel domains in prokaryotes that are fused to CNB domains include the HisKs that are involved in bacterial two component signaling, and the AAA class of ATPases , which coordinates with the phosphate group of cAMP  from those that bind to other ligands? In order to address this question we used the CHAIN  program, which quantifies the differences between two functionally divergent groups of sequences using statistical methods . Using tThe key residues that distinguish the canonical PBC containing protein families from the ones that diverge from this motif are shown in Figure Recent NMR studies on the PKA regulatory subunit had suggested a key role for the β2-β3 loop in coupling cAMP signals to distal regulatory sites . SpecifiA global analysis of CNB domain containing sequences in the public and GOS data has provided novel insights into the evolution of CNB domain structure and function. Two evolutionary events appear to have contributed to CNB domain functional divergence, domain recombination and sequence variation. The sequence diversity observed within the PBC suggests that the CNB domain has evolved as a scaffold for not only binding cAMP, but also a wide variety of other ligands, many of which are yet to be characterized. Statistical comparison of the evolutionary constraints acting on the canonical PBC motif containing CNB domains with the non-canonical ones reveals that the residues in the PBC region have co-evolved with residues in the β2-β3 loop. Examining these constraints in light of structural and biochemical data provides a model of allosteric regulation, which is likely conserved in all cAMP binding modules. The results described in this study have implications for protein engineering and for the design of allosteric inhibitors.CNB domains in GOS and NR data were identified using a combination of psi-blast  and GibbCNB domains identified from NR  were multiply aligned using the CHAIN analysis program . The aliBecause CNB domains in the GOS data displayed significant sequence similarity to known CNB domains, they were assigned to one of the 30 families by running them against 30 family specific blast profiles. The taxonomic assignment for the GOS sequences was likewise done based on their similarity to known NR sequences . ExaminaIn order to visually examine the evolutionary relationship between the identified sequences, we first constructed a phylogentic tree of all the 7,696 CNB sequences. The resulting tree, however, was very complex and hard to interpret. Therefore, we decided to take an alternative approach where we depicted each family by a consensus sequence. The 30 consensus sequences, corresponding to each of the 30 families, were generated from multiple alignments of individual families. The neighbor joining algorithm as implemented in the Molecular Evolutionary Genetics and Analysis (MEGA) program  was usedThe evolutionary constraints imposed on CNB sequences were measured using the CHAIN program . In brieThe sequence identifiers for the sequences used in alignments Figures CAP/CRP, catabolite activator protein; CBS, cystathionine beta synthase; CNB, cyclic nucleotide binding; GOS, Global Ocean Sampling; HisK, histidine kinase; HTH, helix-turn-helix; NR, National Center for Biotechnology Information's non-redundant amino acid database; PBC, phosphate binding cassette; PK, protein kinase.NK and SST conceived and designed the experiments. NK, JW performed the experiments. NK and SST analyzed the data. AFN, SY, GA and JCV contributed reagents/materials/analysis tools. NK and SST wrote the paper.


Cognitive impairment is gaining recognition as sequelae of heart failure and the ICCU environment adds to their worsening symptoms.To determine cognitive dysfunctions in patients with heart disease admitted in intensive cardiac care unit (ICCU) and to compare it with patients admitted in general medical wards with heart disease.A total of 30 patients admitted to ICCU with heart disease were taken for the study and compared to patients with heart disease admitted in general medicine wards (except ICCU). The tools used were SMMSE  and BCRS . Statistical tests used were Student ‘t’ test and Chi-Square test.This study showed cognitive dysfunctions in the domains of orientation, attention and constructional ability as measured by SMMSE and cognitive dysfunction in the domain of concentration as measured by BCRS. Overall cognitive dysfunctions were present in the total score of both SMMSE and BCRS scale, which was statistically very highly significant.The results showed that the patients in ICCU had cognitive dysfunctions in the domains of orientation, attention, constructional ability and concentration. Overall cognitive dysfunctions were found in the total scores of SMMSE and BCRS, thus signifying a global cognitive deficit. Chronic heart failure and cognitive impairment are common problems in the elderly. Both are associated with increased mortality and disability. While these conditions may occur by chance in the same individual, there is increasing evidence that heart failure is independently associated with cognitive impairment.Cognitive impairment is a common and potentially reversible condition among patients with heart failure, particularly in the elderly. It is described to be associated with an almost five-fold increase in mortality in patients with chronic heart failure.Both these conditions are associated with increased morbidity, mortality, disability, decrease in quality of life and increased health care costs. Though these conditions may occur together in the same individual, there is increasing evidence that heart failure is independently associated with cognitive impairment. Results show that death occurred in 18% of those who had cognitive impairment with respect to 3% of those with normal cognition. Thus, cognitive impairment is proposed to be an independent prognostic marker in patients with heart failure. Hence simple cognitive screening test should be a part of the routine assessment.The mechanism of cognitive deficits in cardiac patients is unclear and it may be related to multiple infarcts, acute or chronic hypoxic damage secondary to arrhythmias, cardiac failure, or small vessel disease of the brain.Congestive cardiac failure is a frequent complication of most diseases of the heart and associated with impairment in several aspects of the quality of life of patients, including mood and cognitive performance. Patients with congestive cardiac failure display deficits in memory and other intellectual abilities, which may be the reason for poor follow-up rates and poor drug compliance.The mechanism of cognitive deficits in cardiac patients is unclear as it may be related to multiple infarcts/emboli, acute or chronic hypoxic damage secondary to arrhythmias, cardiac failure, hypo perfusion and small vessel disease of brain, but to identify the exact cause in these patients with heart failure is difficult to determine.Abnormalities of mental functions are common problems in congestive cardiac failure patients, which are more frequent and more serious as the heart failure progresses. Cardiac output and cerebral blood flow are preserved due to compensatory mechanism in mild heart failure but can be severely compromised in advanced heart failure. Drugs used to treat heart failure, especially digitalis, can produce a wide variety of mental aberrations including delirium.During hospitalization, up to 72% of the patients had mild to severe impairment in one or more cognitive areas, delayed recall being the most common deficit during hospitalization. Six months later, 29% of the patients continued to be impaired and all had deficits in delayed recall.The cognitive functions that were most often impaired in patients with chronic heart failure were short-term verbal memory, short term visual spatial memory, differed verbal memory, verbal learning and visual spatial logical ability. The high prevalence of short term verbal memory impairment has important implications in clinical practice since congestive cardiac patients should be actively involved in medical management of their disease. Memory deficits could compromise patient’s adherence to the treatment.Memory and attention deficits are the most frequently occurring cognitive impairment, followed by slowed motor response times and difficulties in problem solving. Prevalence rates range from 30 to 80%. Most patients have mild impairment, although as many as one fourth may have moderate to severe cognitive impairment. Cerebral infarction and cerebral hypo perfusion either alone or in combination might be the underlying pathophysiology.Micro embolization and cerebral hypo perfusion were implicated for neurocognitive dysfunction in chronic heart failure. Other causes of cognitive decline may include prior cardiac surgery, chronic hypertension; sleep disordered breathing, hyper homocysteinemia and dementia of ageing. The discovery of neurocognitive defects in heart failure must prompt a well constructed diagnostic evaluation to search for the underlying cause since this process might be at least partially reversible in many cases.Hemodynamic alterations due to heart failure and cognitive deteriorations are very frequently associated in aging, increasing morbidity and mortality risk. Psychosocial variables such as illiteracy, depression and particularly cognitive deterioration determine a significant increase of the risk to develop heart failure. Attention should be paid to encourage mild physical activity to provide emotional support to patients and also to assess their general cognitive abilities. Hence multidimensional approach is necessary to better characterize and treat elderly patients in particular those with congestive cardiac patient.Low-output states such as systemic hypotension and low Abnormal prevalence of cognitive dysfunction has been reported in middle aged patients with end stage heart failure. Increasing age and lower indices of left ventricular function were associated with worsening cognitive performance. However, the linkage between ageing, left ventricular systolic function, and cognitive performance remains elusive. CognitivArterial hypotension has been associated with increased risk of dementia in some large prospective studies; and cognitive impairment is common among elderly with left ventricular function. As early treatment of cardiac low-output states can reverse cognitive dysfunction, the routine management of heart failure should include systematic assessment of cognitive performance.In patients with heart failure, cognitive impairment may be intermittent or subtle in the early stages and thus not easily recognized. If so, routine screening is essential to ensure that cognitive impairment is detected and addressed as quickly as possible. In order to do so, practical, time-efficient, and sensitive measures are needed. Cognitive screening tools should be tested against a reference standard, such as a clinical neuropsychological battery, so that the sensitivity and specificity of simple measures for detecting cognitive impairment in patients with heart failure could be identified.Systematic neuropsychological testing of older patients with heart failure for early diagnosis of cognitive impairment might identify those who may most benefit from prompt echocardiographic evaluation and aggressive treatment of left ventricular dysfunction. Such a multidisciplinary approach to older patients with heart failure may play a key part in reducing the burden of so called "circulatory dementia" in advanced age, as the prevalence and incidence of heart failure are rapidly increasing, and substantial decreases in cognitive function have been associated in general populations with diagnosis of cardiovascular diseases.To determine cognitive dysfunctions in patients with heart disease admitted in ICCU and compare with patients admitted in general medical wards with heart disease.Subjects for the study were selected from the inpatient facility of Department of General Medicine, Father Muller’s Medical College, Mangalore (Karnataka).Thirty subjects diagnosed as having cardiac disease, admitted in ICCU, were chosen randomly. Initial contact was made in ICCU after three days of admission. An informed consent was obtained from those who were willing to participate in the study. Investigations; like Liver Function Tests (LFT) to rule out any liver disease, Renal Function Tests (RFT) to rule out any renal disease, Random Blood Sugar (RBS) for diabetic status, Serum Electrolytes, ECG and Cardiac Enzymes - CPK, CKMB; were done to rule out systemic disorders which may be causative of cognitive dysfunctions.Patient admitted in ICCU with heart diseasePatient admitted in general medical wards with heart diseaseAge: 18-64 yearsPatients who stayed for at least three daysPatients < 18yrs and >64 yearsHistory of substance use within one week prior to admission except tobacco and social use of alcoholAny psychiatric consultation in last one monthPatient with known history of any chronic organic mental illnessPatients with multiple chronic diseases causing cognitive impairment like neuro-degenerative disease, thyroid and adrenal disorders, renal disorders, cancers and strokePatients who were critically ill and who cannot participate in the study like patients on respiratory or ventilatory supportAfter screening, the patients who met the inclusion criteria were taken into the study for detailed assessment.Semi – Structured Proforma Standardized Mini-Mental State Examination (SMMSE)Brief Cognitive Rating Scale (BCRS)Type of Study: This is a cross sectional study.Results of the study observed are as shown in Table - A significant number (73.3%) of patients in this study were assessed on the third day of admission following which they were noticed to be having cognitive dysfunctions.et al.[The cognitive dysfunctions of the intensive cardiac care unit (ICCU) patients in the present study were comparable to those found at the time of hospitalization in a previous study, conducted by Sauve et al.However, et al. three moet al. as ours In this study, majority of the patients were diagnosed as having myocardial infarction (50%), unstable angina (33.3%) and congestive cardiac failure (10%). No other previous studies have mentioned the commonest medical diagnosis in their sample.et al.[et al.[et al,[et al.[et al.[et al.[et al.[On SMMSE cognitive domains like orientation and attention were statistically very highly significant and the domain of construction was statistically significant . The domet al.and Sauvel.[et al. The domal.[et al,Almeida el,[et al. and Bennl.[et al. but was l.[et al. which shl.[et al.The SMMSE scale did not show any statistical significance in the domains of registration, recall and language . This wa13et al.[Results of the BCRS scale showed a statistically very highly significant deficit in the domain of concentration . This waet al.et al,[37et al[et al[et al[Other domains assessed using BCRS scale such as recent memory, past memory, orientation and functioning and self-care were statistically not significant . This waet al, which shet al,379 and a,[37et al which shFinally, in the SMMSE scale and BCRS scale the overall total scores in cases showed results, which were statistically very highly significant Tables  and 5. T1519The results of socio-demographic variables showed that the mean age was 51.53 years, majority being males, married, residing in rural areas, educated up to primary school and earning less than Rs. 2,500/- per month.Occupational background showed that there were 26.7% farmers / coolies, 26.7% housewives and 20% non-agricultural laborers.SMMSE score showed deficits in the domain of orientation, attention and constructional ability.BCRS score showed deficits in the domain of concentration.Overall cognitive decline was observed on both SMMSE and BCRS scores.Signifies the presence of global cognitive deficit.This study was limited by the small sample sizeSubgroup analysis was not doneOther etiological factors of cognitive impairment like – age, severity of illness, medications, nutritional deficiencies, depression, infection and fluid shifts were not considered.This was a cross sectional study with a small sample size, but the study reveals that patients with heart failure in ICCU had more cognitive impairments than the patients in general medical wards. This is supported by the data from earlier studies. These cognitive states may be reversible if detected early, as is supported by the data.Future research needs to focus on:determining the types, frequency, and severity of impairments in cognitive functioning among a sample of heart failure patients,explicating the pathological mechanisms and the clinical factors that underlie the development of cognitive deficits,identifying the ways cognitive impairment influences quality of life, andfollow-up studies; studies assessing cognitive dysfunction at six months and one year follow-up may be helpful as they may be correlated with the severity of heart disease, presence of depression and permit the clinician to take decision in the treatment issues.


Cardiovascular disease incidence rates have long been known to significantly differ between the two sexes. Estrogens alone fail to explain this phenomenon, bringing an increasing amount of attention to the role of androgens. Contrary to what was initially hypothesized, androgens seem to have an overall cardioprotective effect, especially in men. Recent studies and published data continue to support this notion displaying a consistent inverse correlation with atherosclerosis progression and cardiovascular disease both in regressive and prospective study models. Clinical studies have also revealed what seems to be a differential androgenic effect on various cardiovascular risk factors between men and women. Further insight indicates that in order to avoid confusion it may be also preferable to separately examine the effects of endogenous androgen levels from exogenous testosterone administration, as well as discern the differential results of low to normal and supraphysiological administration doses. This review summarizes old and recent data according to the above distinctions, in an attempt to further our understanding of the role of androgens in cardiovascular disease. Cardiovascular disease is characterized for displaying a significant difference in incidence rates between men and women. Even after adjusting for all major risk factors, men have a two-fold risk to die from coronary heart disease compared to women, a fact that remains consistent across various ethnic and social groups . It was Androgens, like most hormones, are partly difficult to study due to their physiological concentration variability. Their serum levels display a circadian and circannual variation . FurtherThe aim of this review is to summarize recent findings on the effects of androgens on most of the aforementioned components of cardiovascular disease and highlight points of interest that can help shed some light on the controversial findings regarding sex steroids and their effects on the human heart and vasculature.The most obvious starting point in the quest for examining the role of androgens on cardiovascular disease is looking for differences in androgen levels between healthy men and men that already have a history of heart disease. Based on the assumption that androgens have a deleterious effect on the male cardiovascular system, researchers from as early back as 1979 had tried to detect differences in testosterone levels in men that had recently presented with acute myocardial infarction. Surprisingly enough, it was soon noted that testosterone levels tended to be normal prior to infarction, decreased shortly afterwards and normalized approximately a year later .Later reviews of published data continue to mention that in almost half of the studies examined, men with a history of a coronary artery disease had a higher prevalence of hypoandrogenemia -18. It wThe possibility of a hitherto unknown protective androgen effect against acute cardiovascular events was initially met with enthusiasm, but a number of prospective cohort studies quickly dashed that hope since none of them could establish the predictive value of testosterone levels for myocardial infarction or stroke after adjusting for other relevant confounding factors ,17.et al, none of their 17 control patients that suffered from severe valvular disease, and were thus under heavy stress from a non-atherosclerotic heart condition, displayed similarly low levels of testosterone. If hypotestosteronemia could be attributed to stress, then one would at least expect testosterone levels to further decrease in more severe cases of coronary disease, which apparently is not the case. Hopefully future research will provide more insight into this small conundrum.The alternative option that low testosterone levels might be a consequence of stress was thus examined more closely. However, this theory could not explain the fact that testosterone levels remained low several months after the occurrence of a myocardial infarction. Furthermore, while one older study among 55 men claimed that testosterone and free testosterone inversely correlated with the degree of coronary disease after adjusting for age and BMI (body mass index) , a more Since looking into the level differences in men with an already existing positive history of heart disease could yield no conclusive conjecture, researchers shifted their focus to a more progressive approach of the effects of androgens in the cardiovascular system. Thus, a large number of clinical studies have attempted to investigate the possible effects of endogenous androgen levels on the progression of various atherosclerotic indices, aspiring to reveal their involvement in a more ongoing setting. Unlike in other aspects of androgen action in the vasculature, the resulting data here seem to be more consistent, attributing androgens with a clearly positive influence on atherosclerotic outcomes.Carotid artery intima-media thickness (IMT) estimated via carotid ultrasonography is one of the most popular markers used to investigate the progression of atherosclerosis. A number of studies focused on correlating carotid ultrasonography results with androgenic hormone measurements seem to have reached similar conclusions. In all cases, subjects located in the higher tertiles for testosterone levels corresponded with statistically significant lower IMT values compared to subjects in the lower testosterone quartiles. Interestingly enough, this finding persisted in both genders and was consistent in all patient groups, including both premenopausal and postmenopausal women, as well as young and old male adults  via transesophageal echocardiography (TEE) and validated its negative correlation with total serum testosterone [et al investigated mean hormonal levels in relation to aortic atherosclerosis using radiographic detection of calcified deposits in the abdominal aorta as an indicator of the presence of atherosclerotic lesions [While carotid IMT measurements are indeed very popular, a few studies have focused on atherosclerotic manifestations of the aorta instead. Demirbag osterone . Hak et  lesions . Among tet al focused on coronary angiogram results [et al, who investigated coronary artery disease in men that had not previously exhibited acute ischaemic manifestations and in whom testosterone and free testosterone levels were found to negatively correlate with the angiography findings after adjusting for age and body mass index (BMI) [Likewise, English  results , making ex (BMI) .The fact remains however that we have yet to determine which of the aforementioned hormonal measurements presents with the strongest or more consistent correlation to any of the above atherosclerotic markers. While all remained in agreement of the protective effect of androgens in the progression of atherosclerosis, each of the aforementioned studies indicated a different androgenic hormone measurement as significantly associated with its results. This may be attributed to the variability of each of the patient samples or the array of risk factors used to adjust these findings and the large divergence in study designs. It still remains though something that we should further clarify if we ever plan to use one of these measurements both for research and practical purposes.Although different in its nature from atherosclerotic progression per se, the regulation of endothelial function and vascular tone in general remain an important component of vascular physiology and predictor of cardiovascular disease. The mechanisms underlying the pathophysiology of impaired vascular tone regulation and thus the emergence of arterial hypertension are very complex and beyond the scope of this study. It is nevertheless important to attempt to summarize the more important androgen effects that have been recently reported.According to a longitudinal study among 206 men, testosterone levels measured 5–10 years prior proved to be an independent negative predictor factor for arterial stiffness after adjusting for other risk factors , an earlThe rapid onset of testosterone's acute vasodilatory action and the fact that it was not abolished by flutamide, an AR (androgen receptor) blocker , led to The same study however also reported that the added effect of AR-deficiency and low testosterone levels in Tfm mice led to impaired endothelial function and voltage-operated calcium channel (VOCC) activity. While this argues against the release of endothelium-derived products or the inhibition of VOCCs as the underlying mechanism for testosterone's acute vasodilatory action, it does have implications for the development of systemic arterial hypertension.In concordance with this, another study discovered that congenital hypogonadal men displayed distinctly impaired vascular reactivity in resistance arteries, as opposed to conduit arteries, due to reduced endothelium-dependent (via reduced NO availability) and endothelium-independent vasodilation . What isIn addition to their effects on the progression of atherosclerosis in general, clinical studies have also attempted to separately investigate the relationship between androgens and some of the major risk factors that are often being adjusted for. These mostly include cross-sectional studies that attempt to correlate various hormone levels with a wide set of well established cardiovascular risk factors. To avoid any confusion, these should be differentiated from studies that investigate exogenous testosterone administration or special conditions which result in supraphysiological endogenous androgen levels, since it has been argued that the effects of androgens may vary in these cases.It is mostly agreed upon that androgens have a favorable effect on cardiovascular risk factors in men ,16. NeweUnfortunately, the same protective effect does not extend to the female population. Contrary to men, higher endogenous testosterone levels have been claimed to have an adverse effect on women's lipid profile . Indeed,An interesting observation at this point is the apparent effect of androgens on Lp(a) (lipoprotein a). Lp(a) is considered an independent risk factor for cardiovascular disease and is distinctly known for its strong genetic component. Admittedly, at least one study among women has failed to establish a relationship between endogenous testosterone concentrations and Lp(a) levels . We shouAndrogens are further related to another very significant cardiovascular risk factor: obesity. Morbid obesity in men has been associated with decreased androgen levels, while serum testosterone levels in general inversely correlate with visceral fat mass ,17,29,38Indeed, most if not all recent studies confirm that DHEA-S, free serum testosterone, total serum testosterone and FAI inversely correlate with not only BMI, but also waist-to hip ratio (WHR) and total body fat mass measurements in men ,13,22,34Such an obvious link between androgens and obesity however raises another interesting question. Could we perhaps attribute the relationship between androgens and other risk factors, such as serum lipid concentrations and insulin sensitivity, to their effects on body fat mass? It seems entirely logical that lower BMI and WHR measurements might conclude in a more favourable lipid profile, acting as a confounding factor . Howeveret al attempted to study the link between androgens and various cytokines among other things in elderly men, and managed to confirm a statistically significant inverse correlation between free serum testosterone levels and CRP (C-reactive protein), IL-6 (interleukin-6) and sICAM-1 (soluble intercellular adhesion molecule 1) [Finally, an interesting novel notion has recently turned scientific interest towards the investigation of the possible immunomodulating effects of testosterone . Yang etecule 1) . This, cWhen looking into the effects of androgens on cardiovascular disease, exogenous testosterone treatment should be examined separately from the effects of its endogenous counterpart in order to avoid confusion. The reason for this is that exogenous intervention seems to wield different results from the spontaneous fluctuation of endogenous androgen levels. As a result, despite the clearly cardioprotective actions of androgens in men, if not in women as well, the matter of testosterone supplementation is one that requires further research on its own.Another important point we need to stress is the necessity to differentiate between testosterone administration in low-normal and supraphysiological doses, as well as between hypogonadal and eugonadal men. For example, when examining the effects of testosterone administration on plasma lipids, it becomes apparent that supraphysiological doses of androgens lower HDL concentrations and mildly increase LDL and total serum cholesterol ,29,38. TBoth testosterone administration and anabolic steroid use seem to decrease PAI-1 and fibrinogen in men and women, attesting to androgens' anticoagulatory and fibrinolytic effects ,17,29,40It has already been mentioned that obesity has been associated with decreased testosterone levels, a relation that was initially attempted to be attributed to either increased peripheral aromatization to estrogens or decreased SHBG concentrations. Further attesting against these two theories is the observation that testosterone replacement in hypogonadal men can effectively reduce whole body fat mass in a dose-dependent manner ,16,29,38The matter of exogenous androgen administration in women can also prove fairly interesting. A 20-year observation study of testosterone administration among 293 female-to-male transsexuals reported no increase in cardiovascular deaths  even thoet al attempted to investigate an alternative option to outright testosterone treatment: the administration of anastrozole, an oral aromatase inhibitor. Anastrozole was able to normalize testosterone levels in hypogonadal men and reduce estradiol levels. Contrary to testosterone treatment however, no significant changes in either lipid profile or inflammation markers were detected, which was partly attributed to the mixed effects of increasing testosterone and reducing estradiol levels [Finally, it should also be mentioned that Dougherty l levels .After the initial disregard concerning their role in cardiovascular disease, androgens are now increasingly attracting scientific interest. A large array of data testifies in favor of a variety of cardioprotective androgen effects in men mostly, but in many cases in women as well. Different endogenous androgenic hormone measurements have been associated with the progression of atherosclerosis and an inverse correlation was almost always displayed in both men and women. On the other hand, total serum testosterone levels and the free androgen index seem to differentially associate with various risk factors in men and women, which mainly consist of various parameters of the lipid profile, arterial blood pressure, diabetes and obesity. Following the verified existence of interacting mechanisms at the molecular level, certain associations between androgens and circulating inflammatory markers have been established as well.In order to avoid confusion, exogenous testosterone treatment should be examined separately from the effects of endogenous androgen levels. The same applies for different levels of administration doses. Testosterone supplementation in low to normal levels in hypogonadal men has mostly been shown to benefit the subjects receiving it, although not to the degree perhaps one would expect from the many positive effects of its endogenous counterpart. Testosterone administration in supraphysiological doses however, along with anabolic steroid abuse, seems to adversely affect both the lipid profile and insulin sensitivity in men. Its effects in women have yet to be researched in depth, while an attempt to replace testosterone treatment with oral aromatase inhibitors failed to produce any significant results.In conclusion, it can be claimed beyond doubt that androgens play an active role in the appearance and progress of cardiovascular disease. As the debate on the role of estrogens continues, understanding the minutiae of the implication of androgens becomes increasingly important, while by attempting to further clarify the details of that implication we can also understand the mechanisms underlying cardiovascular manifestations in general.HRT: hormone replacement treatment; BMI: body mass index; IMT: intima-media thickness; TAIT: thoracic aorta intima thickness; TEE: transesophageal echocardiography; DHEA-S: dehydroepiandrosterone sulfate; FAI: free androgen index; HDL: high-density lipoprotein; DHEA: dehydroepiandrosterone; Lp(a): lipoprotein a; GnRH: gonadotrophin-releasing hormone; PAI-1: plasminogen activator inhibitor-1; SHBG: sex hormone-binding globulin; WHR: waist-to hip ratio; PCOS: polycystic ovaries syndrome; CRP: C-reactive protein; IL-6: interleukin-6; sICAM-1: soluble intercellular adhesion molecule 1; AR: androgen receptor; Tfm: testicular feminized; DHT: dihydrotestosterone.The authors declare that they have no competing interests.PM selected all reference material and drafted the initial manuscript. Consequently all authors contributed equally in the development of the article's viewpoints and its critical revisions. All authors read and approved the final manuscript.


Systemic sclerosis (SSc) is a chronic autoimmune disorder characterized by progressive fibrosis of the skin and visceral tissues as well as a noninflammatory vasculopathy. Vascular disease in systemic sclerosis is a major cause of morbidity and mortality among nonpregnant patients with SSc and is even a bigger concern in the pregnant SSc patient, as the underlying vasculopathy may prevent the required hemodynamic changes necessary to support a growing pregnancy. Vascular manifestations including scleroderma renal crisis and pulmonary arterial hypertension should be considered relative contraindications against pregnancy due to the high associations of both maternal and fetal morbidity and mortality. In contrast, Raynaud's phenomenon may actually improve somewhat during pregnancy. Women with SSc who are considering a pregnancy or discover they are pregnant require evaluation for the presence and extent of underlying vasculopathy. In the absence of significant visceral vasculopathy, most women with SSc can expect to have reasonable pregnancy outcomes. Systemic sclerosis (SSc) is a chronic autoimmune disorder characterized by progressive fibrosis of the skin and visceral tissues as well as a non-inflammatory vasculopathy manifesting as Raynaud's phenomenon, digital ulcerations, pulmonary arterial hypertension, and scleroderma renal crisis. Vascular disease in systemic sclerosis is a major cause of morbidity and mortality among non-pregnant patients with SSc. There are two main subsets of SSc: diffuse cutaneous disease is characterized by cutaneous fibrosis proximal to the forearms and is associated with higher incidence of scleroderma renal crisis and pulmonary fibrosis; limited cutaneous disease has more limited cutaneous involvement to the distal extremities and face and is associated with higher prevalence of digital ulcers and pulmonary arterial hypertension. Akin to many autoimmune diseases, SSc has a strong female predominance, with an approximate female- to male- ratio of 5 : 1 . SSc is In order to accommodate the enlarging uterus and growing fetus, a pregnant woman's body must make numerous physiologic hemodynamic changes. Many of these changes involve changes in blood volume, vascular resistance, cardiac output, and oxygen consumption. Most physiologic changes begin early in gestation and peak by the late second trimester of pregnancy. Although not definitive, it has been suggested that an initial fall in systemic vascular resistance leads to the other well-established vascular and hemodynamic changes of pregnancies . ActivatThe exact mechanisms underlying the hemodynamic changes during pregnancy remain to be completely understood. An increase in prostacyclin in both the fetoplacental tissues and maternal system plays a clear role in systemic vasodilation; however, additional mediators are required to explain the degree of reduction in vascular resistance . Nitric Physiologic hemodynamic changes are an integral part of human pregnancy. In some cases, changes in vascular blood flow and decreased vascular resistance may lead to improvement in manifestations of systemic sclerosis. In other cases, an intrinsic inability to adapt to the necessary hemodynamic changes in pregnancy, possibly due to underlying vasculopathy of systemic sclerosis, may contribute to adverse pregnancy outcomes including hypertensive disorders of pregnancy and intrauterine growth restriction.‒15% [Given the prominent vasculopathy associated with SSc, there is concern for an increased risk of adverse pregnancy outcomes associated with vascular compromise or inability to make appropriate hemodynamic adaptations to support a pregnancy. Indeed, early reports suggested very high rates of maternal death during pregnancy –11. It i‒15% , 14 are ‒15% . Preterm‒15% , 14, 16.‒15% , ranged ‒15% , 14, 16.‒15% . This stScleroderma renal crisis, characterized by malignant hypertension, proteinuria, acute renal failure, microangiopathic changes, and the pathognomonic “onion skin” appearance of renal arteries on pathology, is one of the most severe complications of SSc . AffectiUnfortunately, scleroderma renal crisis can be difficult to distinguish from preeclampsia (abrupt onset hypertension and proteinuria) in the pregnant SSc patient; both conditions carry a high risk of severe maternal and fetal complications if not treated aggressively. In situations where the woman has a history of renal crisis or is at high risk for developing renal crisis , an immediate trial of ACE inhibitors may be indicated. In cases of profound maternal or fetal distress, emergent delivery may be the most appropriate option followed by initiation of ACE inhibitor therapy. In this situation, the definitive therapy for preeclampsia has been completed (delivery), and ACE inhibitors can be instituted without concern of risk of fetotoxicity of antenatal ACE inhibitor exposure . Renal bPulmonary arterial hypertension (PAH) has been increasingly recognized as a major cause of morbidity and mortality in the SSc population. Estimates of PAH in the SSc population range from 7.85% to 26.7% , 25. In It is clear that women with PAH are at extremely high risk for severe hemodynamic complications during pregnancy as there is significantly less reserve in the pulmonary arterioles to reduce vascular resistance to accommodate the increased blood volume and cardiac output that occurs during pregnancy. Reports estimate a 36%–50% maternal death rate in women with PAH, with the most vulnerable period occurring with delivery and the first two weeks postpartum , 27. A mIf a woman with PAH discovers a pregnancy and wishes to continue with the pregnancy or if PAH is diagnosed during an established pregnancy, careful hemodynamic monitoring and comanagement with pulmonologists experienced with PAH is essential. Case reports have described successful use of epoprostenol and sildenafil during pregnancy , 30–32. Delivery is a period of extremely high risk in the woman with PAH. Acute hemodynamic changes including increase in cardiac output of 25%–50% during the second stage of labor through delivery with the return of blood volume from the uterus to the main circulation , 27. IncOf all vascular complications of SSc, Raynauds phenomenon and digital ulcers are most likely to improve during pregnancy. Raynauds phenomenon is characterized by vascular hyperreactivity and vasospasm. However, when digital vasculopathy becomes more fixed, as is often the case in SSc, chronic poor perfusion leads to digital ulceration. Raynauds phenomenon tends to improve during pregnancy, only to worsen postpartum . Less isGiven the diffuse vasculopathy present in patients with SSc, there are concerns that the same pathophysiologic changes may occur in the placental vasculature. The higher rates of prematurity and small for gestation age babies seen in SSc pregnancies may be a direct result of placental vascular insufficiency. Most studies did not examine placental tissue, thus not allowing for direct correlation between placental vascular abnormalities and adverse pregnancy outcomes. Histopathologic examination of placentas from a limited number of SSc pregnancies has been reported; all of which reported normal placenta weight for gestational age –36. In oHealthy pregnancies require extensive pulmonary, cardiovascular, and vascular changes to support the fetus during development. An inability to accommodate such changes due to preexisting pulmonary, cardiac, or vascular disease may lead to pregnancy complications and an inability to support the continuance of the pregnancy. Vasculopathy is a prominent feature of SSc in general and may play an important role in adverse pregnancy outcomes in women with preexisting disease. Women with SSc who are contemplating pregnancy or who discover an inadvertent pregnancy should undergo a thorough evaluation for systemic and organ-specific vasculopathy. Those with a history of scleroderma renal crisis or pulmonary arterial hypertension (or patients at high risk for developing these complications) are at the highest risk for maternal and fetal death and other highly morbid complications of pregnancy. Those with or at high risk for renal or pulmonary arterial vasculopathy should be strongly advised against becoming pregnant and to consider termination if a pregnancy occurs. If a woman wishes to continue with a pregnancy after appropriate counseling of risks, aggressive monitoring and co-management with experts in renal or pulmonary arterial disease is mandatory. Medications such as ACE inhibitors and prostaglandins, which can carry risks for congenital malformations or fetal toxicity, need to be considered as the benefits to both mother and fetus may outweigh known risks of antenatal exposure. Labor and delivery is a very vulnerable period in these cases, and patients may require extended observation in the hospital following delivery to watch for acute cardiovascular collapse in cases of PAH.However, if after thorough evaluation, a woman with SSc does not appear to have vasculopathy of the internal organs, pregnancy may be considered. Raynaud's phenomenon should not be considered a contraindication to pregnancy in the absence of renal disease or PAH. With careful monitoring by high-risk obstetrics, most women without advanced vasculopathy can expect to have reasonable perinatal outcomes although preterm delivery is common. Advances in neonatology have helped improve the short- and long-term outcomes of premature infants.Whenever possible, placentas and umbilical cords should be subject to histopathologic examination for evidence of decidual vasculopathy and stromal fibrosis. This will hopefully lead to better understanding of the role of placental vasculopathy in adverse pregnancy outcomes and may additionally provide histopathologic clues to systemic or organ- specific vasculopathy in SSc patients.


The development of selective PAF receptor antagonists may provide a novel approach to the treatment of human bronchial asthma. In preclinical animal models of human asthma, PAF receptor antagonists have been found to be efficacious in blocking antigen-induced changes in lung function. However, the majority of these models involve acute inflammatory events and transient changes in lung function and, therefore, their relevance to human asthma is questionable. In a recent study with a primate model of chronic airway inflammation and hyperresponsiveness, we have shown that treatment with a PAF receptor antagonist had no effect on reducing chronic inflammation and hyperresponsiveness. Similarly, recent studies in human asthmatics with PAF receptor antagonists have failed to show efficacy in blocking allergen-induced airway responses or to have any steroid sparing effects in patients with ongoing asthma. Thus, it seems that PAF may not be a key mediator which can be blocked and thereby provide therapy for bronchial asthma.


Schistosoma infection intensity and prevalence within endemic communities, including exposure-related factors such as local environment and behaviour, and factors relating to susceptibility to infection such as immunology and genetics. While animal studies performed in the laboratory can be tightly controlled, human populations are highly heterogeneous, varying according to demographic characteristics, genetic background and exposure to infection. The heterogeneous nature of human water contact behaviour in particular makes it difficult to distinguish between a lack of cercarial exposure and reduced susceptibility to infection as the cause for low levels of infection in the field.Numerous factors may influence Schistosoma mansoni infection in a rural Ugandan fishing community receiving treatment as part of a multi-disciplinary longitudinal reinfection study. More specifically, we examine the influence that age, sex and ethnic background have on susceptibility to reinfection after anti-helminth drug treatment, but use individual estimates of cercarial exposure and multivariable methods in an attempt to remove noise created by environmental and behavioural heterogeneities. We then investigate whether schistosome-specific IgE immune responses could account for any remaining variations in susceptibility to reinfection. Our findings suggest that observed ethnic- and sex-related variations in S. mansoni reinfection were due to variations in cercarial exposure, as opposed to biological differences in susceptibility to infection. Age-related differences in reinfection were not explained by exposure, however, and appeared linked to the balance of IgE and IgG4 to the tegumental antigen SmTAL1 (formerly Sm22.6), which itself was significantly related to resistance to reinfection.In this study we investigate risk factors for This study highlights the benefit of taking a multidisciplinary approach in complex field settings; it allows the ecology of a population to be understood and thus more robust conclusions to be made. Schistosoma mansoni reinfection could be explained by differences in exposure, age-related differences appeared linked to the balance of specific IgE and IgG4 antibodies, themselves related to resistance to reinfection. Our study highlights the benefits of a multidisciplinary approach in complex field settings: it improves our understanding of a population's ecology and therefore the biology of disease.Human schistosomiasis is a chronic parasitic disease affecting around 200 million people worldwide. Infection occurs when cercariae penetrate the skin during water contact. Although there is effective treatment for schistosomiasis, individuals remain susceptible to reinfection after treatment; some individuals, however, appear more susceptible to reinfection than others. The highly heterogeneous nature of human water contact behaviour makes it difficult to identify whether low levels of reinfection are caused by immunity or a simple lack of cercarial exposure; this complicates the characterisation of risk factors for infection and immune correlates of protection. Here, we take a multidisciplinary approach using individual estimates of cercarial exposure and multivariable analysis to allow for environmental and behavioural heterogeneities. We examine the influence of demographic factors and antibody responses on susceptibility to reinfection. While observed ethnic- and sex-related variations in  Schistosoma spp. Despite numerous control efforts, the estimated worldwide prevalence of schistosomiasis has not changed over the past 50 years Unfortunately, the heterogeneous nature of human water contact behaviour, and therefore cercarial exposure (the infectious stage of the parasite), impedes our ability to distinguish between immunity and simply a lack of cercarial exposure as the root cause for low levels of infection. For example, the characteristic age-infection curves observed in schistosomiasis-endemic communities, whereby infection intensities peak in early adolescence and decline thereafter, is believed to be evidence that acquired immunity to infection can develop. In support of this, IgE antibody levels to worm antigens, which have been linked to resistance to reinfection Schistosoma that infect man Numerous studies have also documented differences in schistosomiasis infection prevalence or intensity between males and females living in the same community, with males frequently having heavier infections than females . Starting in July 1998, study members were treated twice, two weeks apart, with 40 mg/kg body weight of praziquantel. Parasitological surveys were conducted in May 1998, prior to treatment, and 5 weeks, 12 months, 18 months and 22 months after the second treatment. Since water contact was only followed for 11 months following treatment, we limited our analysis to reinfection at 12 months. 5 week stool samples were used to detect treatment failure or non-compliance. Pre- and post- treatment stool samples were collected on three consecutive days, and for each stool sample, two 50 mg Kato-Katz Systematic water contact observations conducted on the whole community between mid November 1998 and early September 1999 at 19 different sites were used to estimate study participants' water contact duration. Full details of these observations are given elsewhere iX is the exposure score for the thi individual, observed in times, with the thj contact lasting jidur minutes. jiSite, jihr and jideg are the respective site, time of day and degree of immersion weightings for the thj contact. Full details of these weightings are given in jisite), which described the snail infection intensities and the relative abundance of Biomphalaria stanleyi vs. B. sudanica at each site, the former of which appears to be a more susceptible host and have a greater capacity as an intermediate host jihr) reflected the diurnal rhythms of cercarial shedding and were constructed using a bell-curve function Where Spearman-Brown split-half coefficients , but less likely in the Bagungu [OR = 0.54 ] and also varied with age, peaking in the 10–12 year olds and declining with age thereafter. As for before treatment, reinfection peaked earlier in the Alur than the Bagungu , P<0.0001] and borderline significantly lower amongst males compared with females ; however, significant interactions were found between ethnic group and sex (P<0.0001), suggesting that associations between sex and reinfection differed in the two ethnic groups. Reinfection was borderline significantly associated with age .To assess whether the observed demographic variations in reinfection could be due to differences in susceptibility to infection, further analyses used multivariable models to investigate whether differences in reinfection could be explained by differences in water contact behaviour or cercarial exposure . In an aP = 0.07), suggesting that any differences in the effect of age on reinfection observed in the two ethnic groups were due to differences in duration of water contact. After adjusting for duration of water contact  P = 0.54, males vs. females], but ethnicity remained significantly associated with reinfection  and the different influence of sex observed in the Alur and Bagungu ethnic groups also remained significant .This ethnic group-age group interaction was lost once duration of water contact was allowed for in analysis .When estimated cercarial exposure was included in the logistic regression model for reinfection the different effects of both age and sex observed in the two ethnic groups when exposure was not allowed for were no longer significant  (results not shown). Age remained significantly associated with reinfection after adjusting for SWA -IgE and -IgG4, and SEA –IgE and –IgG4 (P≤0.03).Schistosoma infection are often limited by their lack of data on individual-level cercarial exposure  and therefore are unlikely to have been important in transmission. Issues such as these may be resolved with the advancement of global positioning system (GPS) technology There are some limitations to consider when interpreting the results from this study. Firstly, although deemed the gold standard for measuring water contact behaviour The qualitative data collected subsequent to the water contact observations also suggest that behaviour in Booma may have altered since the observations were made: there is evidence that the Bagungu in particular have made a concerted effort to change their behaviour in order to avoid infection. Therefore, because water contact behaviour was only measured for the first 11 months following treatment, we decided to limit our analysis to reinfection observed during the first 12 months after treatment, so as not to bias results. Whilst limiting our analysis to the first 12 months of reinfection meant that we had to restrict analyses to a binary response (reinfected vs. not reinfected) due to the low levels of reinfection seen in our study population, it did have the advantage of being less subject to noise; immune responses measured 7 weeks after treatment are likely to be more closely related to reinfection at 12 months than at 18 and 22 months.et al. noted that the level of the lake surrounding Booma is increasing, which seems to be influencing the population dynamics of the Biomphalaria species inhabiting the Lake and therefore possibly S. mansoni transmission Reinfection was low in Booma, particularly given the high intensities and prevalence of infection seen before treatment. One explanation is a reduction in transmission as a result of treatment, as has been observed elsewhere SchistosomaIn the univariable analysis, sex was significantly associated with reinfection, with males having a greater likelihood of reinfection than females. Greater prevalence or intensities of infection amongst males have been documented elsewhere for all three of the major species of Similar to reports made by Kabatereine and colleagues Schistosoma infection can develop; the fact that variations in exposure were able to explain sex- and ethnicity- related differences in reinfection in our study strengthens this conclusion.Age-infection profiles in this study were typical of schistosomiasis-endemic communities: infection was greatest in children and comparably lower amongst adults. There has been some debate as to the relative importance of exposure vs. susceptibility to infection in explaining the characteristic age-infection curves observed in endemic communities 4. This is in agreement with other studies that have indicated that whilst a strong IgE response to adult worm antigens may protect against schistosome infection, a strong IgG4 response directed against adult worm antigens may actually increase susceptibility to infection 4 is known to modulate the effects of IgE by attenuating the ability of IgE to mediate certain effector mechanisms, both in allergy4 balance and age; therefore it is not clear whether changes in the balance of these antibodies with age are due to prolonged exposure to antigen, possibly following worm deathSchistosoma spp. infections.Evidence from our study suggests that reductions in infection with age may be linked to changes in the balance of TAL1-IgE and TAL1-IgGa priori confounder in immuno-epidemiological studies, ethnic background is rarely considered, which could have strong implications for study outcomes; we therefore recommend that ethnic background is included as an a priori confounder in all immuno-epidemiological studies. Our study also corroborates previous evidence that the reductions in schistosome infection intensity observed amongst adults in endemic communities are due to acquired immunity to infection; evidence suggests that this could be linked to changes in the balance of IgE and IgG4 to tegumental antigens. These findings highlight the benefit of employing multidisciplinary methodologies to capture and adjust for patterns of exposure in population-based studies where confounders are a major limitation; this will enable firmer conclusions to be drawn regarding the biology of disease, even in complex settings such as ours.In summary, this study took a multidisciplinary approach, drawing on malacological, ecological and behavioural data in order to capture the ecology of our study population. Using previously constructed individual-level exposure scores and multivariable methods, we were able to remove noise introduced due to variations in exposure and thus able to identify potentially immune individuals. We found that exposure to infection varied dramatically depending on both ethnic background and sex, which created strong ethnic- and gender-related differences in infection. While sex is routinely considered an Checklist S1STROBE Checklist(0.03 MB XLS)Click here for additional data file.Tables S1Comparison tables of the analysis with and without 5 week egg-positive individuals.(0.18 MB DOC)Click here for additional data file.


MicroRNAs (miRNAs) are ∼22-nt regulatory RNAs expressed by all multicellular eukaryotes Because miRNAs are potent regulators of gene expression that are both small and non-antigenic, they would seem ideal tools to alter the cellular environment in ways that favor virus replication. While numerous virally encoded miRNAs have, in fact, been described for members of the herpesvirus family, few other viral miRNAs have been identified . In geneAlthough the reason for this pattern of viral miRNA expression remains unknown, one can speculate that viruses that replicate in the cytoplasm  might lack miRNAs because they never encounter the nuclear enzyme Drosha. On the other hand, nuclear RNA viruses  may avoid encoding miRNAs because excision of a genomically encoded pre-miRNA would induce the cleavage and degradation of the viral RNA genome. Finally, one can speculate that viruses that establish long-term, latent infections  would derive more benefit from the use of non-antigenic miRNAs to inhibit cellular antiviral responses than would viruses that have short lytic replication cycles.Only a small number of mRNA targets of viral miRNAs have been defined, so a complete answer to this question is currently not possible. However, the emerging picture Although it is therefore widely believed that viral miRNAs play an important role in the replication and pathogenesis of the viruses that encode them, little evidence in support of this hypothesis currently exists. Indeed, a mutant polyomavirus lacking the only polyomavirus-encoded miRNA replicated indistinguishably from wild-type in infected mice If viral miRNAs do play an important role in viral replication and pathogenesis, then they should be under purifying selection. Indeed, comparison of the genomic sequences of diverse KSHV isolates reveals that the miRNAs encoded by KSHV are, in general, highly conserved, although isolates bearing mutations that block production of individual KSHV miRNAs have been described ORF71 gene in both virus species In contrast, a comparison between distinct but related herpesvirus species reveals far less evidence of miRNA sequence conservation, although the genomic localization of virally encoded miRNAs is often conserved. In the case of HSV-1, which encodes eight known viral miRNAs, and the related but distinct HSV-2, which encodes at least six miRNAs, four miRNAs are partially conserved in terms of sequence, and fully conserved in terms of genomic localization Viral infection represents a cataclysmic event in the life of a cell that generally results in dramatic changes in cellular mRNA expression. These may include the induction of cellular factors that have the potential to resist or promote viral replication. As cellular miRNAs are also transcribed by Pol II, it is expected that viral infection would also affect their pattern of expression. The question then is whether these changes are evolutionarily selected to favor or inhibit virus replication. At present, there is no evidence indicating that viruses modify the cellular environment to selectively favor the processing and expression of viral miRNAs, although viral miRNAs may be expressed at such high levels that they have the potential to competitively inhibit cellular miRNA function.While it has been proposed that HIV-1 infection induces the expression of specific cellular miRNAs While viruses may therefore enhance cellular miRNA expression, the more commonly observed effect is inhibition At least one clear-cut example of a cellular miRNA that facilitates virus replication is known, i.e., activation of HCV replication by the liver-specific miRNA miR-122 An interesting and largely unresolved aspect of the replication cycle of RNA viruses is that their RNA genome must serve several essential yet mutually exclusive roles. Thus, the HCV genome is not only the mRNA that encodes all the viral proteins but also the substrate for the viral RNA-dependent RNA polymerase and the genomic RNA that is packaged into progeny virions. It is interesting to speculate that cellular miRNAs could play a role in retargeting viral RNAs away from translation and towards one of the latter two fates. Of note, RISC is believed to direct bound mRNAs into cytoplasmic processing bodies (P bodies), where they may be translationally repressed and/or degraded, yet emerging evidence suggests that P bodies can also function as sites of viral RNA synthesis


Serotonin transporter clustering is an important feature for regulation of this transporter activity. We used immunocytochemistry to analyze alterations in serotonin transporter clustering in blood lymphocytes of reeler mice. Serotonin transporter immunolabelling is observed mostly as a patchy staining in lymphocytes membranes. Comparison of the number and size of serotonin transporter clusters in wild-type mice, heterozygous reeler mice, and homozygous reeler mice showed an increase in the number and size of clusters in heterozygous reeler mice, but only an increase in clusters size in homozygous reeler mice. Reelin is down-regulated in the brain of schizophrenia, autism, and mood disorders, and is also expressed in blood plasma. There is the possibility therefore that alterations in serotonin transporter clustering in blood lymphocytes associated with a decrease in reelin expression may be operative in some cardiovascular or immune system alterations showing comorbidity with these mental disorders. Protein clustering into specific membrane domains is known to be of importance for membrane proteins functional regulation: the clustering of neurotransmitter receptors into postsynaptic active sites, the formation of the immunological synapse, the partitioning of membrane proteins into lipid raft domains, and the clustering of membrane proteins to be internalized are good examples of that.The serotonin transporter (SERT) belongs to the SLC6 family of sodium- and chloride-dependent integral membrane proteins, and is the primary responsible for the recapture of released serotonin from the extracellular space , 2. The Reelin is a large extracellular matrix protein abundant in brain tissue whose levels are down-regulated in several psychiatric disorders –15. ReelThe primary actions of reelin in the nervous systems are regulating neural migration and synaptogenesis in cortical areas during brain development , and later in stabilizing synaptic contacts onto dendritic spines in the adult brain thereby regulating synaptic plasticity see –21). The. The21])While reelin actions in the nervous system are well studied, there is not so much knowledge about the possible actions of reelin in blood plasma, although it is known that reelin plasma is mostly secreted by hepatocytes , and is Reln−/−) show no detectable levels of reelin in plasma, while the happloinssuficient heterozygous reeler mice (Reln+/−) express reelin plasma levels about one half of those in wild-type (Reln+/+) littermates )+/− mice . At the n et al. . Reln+/− and Reln−/− mice. In fact, it is possible that reelin may be involved in regulating the clustering of multiple membrane proteins, including some neurotransmitter receptors and transporters. Although brain serotonin levels appear to be unaltered in Reln+/− mice, both Reln+/+ and Reln+/− mice show an increase in brain serotonin levels upon early maternal separation of the pups [Reln−/− mice there are important alterations in serotonergic innervations in the neocortex [Reelin has been shown to induce the expression and clustering of some transmembrane proteins in synaptosomes , inducesthe pups . In addieocortex . Therefoeocortex –14. Reeleocortex . Intereseocortex –38, a dieocortex , 40. TakThe results of the present report also invite to consider the actions of plasma reelin actions in SERT clustering in lymphocytes as a possible factor of importance in understanding the comorbidities between some immune and/or vascular systems alterations and these mental disorders.


In the past few years, emergent disease episodes have increased; nearly all have involved zoonotic or species-jumping infectious agents. Because there is no way to predict when or where the next important new zoonotic pathogen will emerge or what its ultimate importance might be, investigation at the first sign of emergence of a new zoonotic disease is particularly important. Such investigation may be described in terms of a discovery-to-control continuum: from recognition of a new disease in a new setting to complex phases involving the hard science disciplines pertaining to discovery, the epidemiologic sciences pertaining to risk assessment, and activities pertaining to risk management. Today, many activities involving zoonotic disease control are at risk because of a failed investigative infrastructure or financial base. Because zoonotic diseases are distinct, their prevention and control will require unique strategies, based more on fundamental research than on traditional approaches. Such strategies require that we rebuild a cadre of career-committed professionals with a holistic appreciation of several medical and biologic sciences.


Simon Capewell and Hilary Graham review different population strategies for preventing cardiovascular disease and conclude that screening and treating high-risk individuals may be ineffective and widen social inequalities. The primary prevention of cardiovascular disease (CVD) is dependent on the effective reduction of the major risk factors for CVD, particularly tobacco control and a healthier diet.The high-risk approach to prevent CVD typically involves population screening. Those exceeding a risk threshold are then given lifestyle advice and/or tablets to reduce blood cholesterol and blood pressure.Evidence suggests this high-risk approach typically widens socioeconomic inequalities. Such inequalities have been reported in screening, healthy diet advice, smoking cessation, statin and anti-hypertensive prescribing, and adherence.The alternative approach is population-wide CVD prevention. For example, legislating for smoke-free public spaces, banning dietary transfats, or halving daily dietary salt intake. Such strategies are generally effective and cost-saving; there is also increasing evidence that they can reduce health inequalities.We conclude that screening and treating high-risk individuals represents a relatively ineffective CVD prevention approach that typically widens social inequalities.Several high-income countries, including the United Kingdom, are tackling “health inequalities” The primary prevention of cardiovascular disease (CVD) is dependent on the effective reduction of the major risk factors, particularly by reducing tobacco use and adopting a healthier diet Assessing the potential effect of risk factor reductions on socioeconomic inequalities in health is crucial. McLaren et al. usefully distinguish between “agentic” prevention strategies  and “structural” strategies  inequalities. This simple arithmetic was spelt out by Diederichsen and colleagues There is increasing evidence to support health equity strategies that take a whole-population approach to CVD risk factors. This includes simply considering arithmetical principles. More recent support came from Kivimaki et al., who quantified the 15-year benefits of decreasing risk factors uniformly across a male population  Smoking rates and exposure to environmental tobacco smoke are higher in poorer groups in Scotland, which is consistent with other high-income countries Strong regulatory policies, particularly those including increases in cigarette price, are also associated with declines in tobacco use of a similar magnitude across socioeconomic groups Social differences are observed in diet, as in smoking. Thus, low-income families consume more saturated fat and fewer fruits and vegetables than more affluent families Of course, the population approach is unlikely to totally abolish inequalities since many of the drivers of disadvantage lie even further upstream. For instance, structural interventions in the Ontario Smoke Free Strategy included smoking bans in enclosed public places and enclosed work places, laws on tobacco sales to minors, and restrictions on the display of tobacco products in retail outlets. Overall smoking rates in the province fell. However, 40% of aboriginal women and men are still smoking, as are 34% of adults with less than a secondary school education compared to 11% who had a bachelor's degree or higher The population approach has a strong ethical base. It is in step with the “stewardship” model of public health that places obligations on governments to enable conditions in which everyone can lead a healthy life However, population-based structural approaches to reduce inequalities might be difficult to achieve. Such approaches ideally require concerted cross-sectoral efforts such as universal access to healthy food, reductions in work place stress, and access to safe environments for physical activity for all In the UK, the high-risk approach for preventing CVD is typified by the health checks programme Putting Prevention First, implemented in England This is a controversial area. Manuel et al. recently “revisited” Rose Likewise, Zulman et al. recently preferred a high-intensity treatment intervention in the US adult population Furthermore, critics of the high-risk cardiovascular risk screening approach suggest that this strategy might have low effectiveness, leave substantial residual risk, and achieve a small population impact at high cost; as well as result in the medicalisation of previously healthy individuals. Furthermore, it does not address the root causes of the problem There is increasing evidence that inequalities in risk factors can widen when effects are mediated through individual-level changes in knowledge, motivation, and behaviour  —the availability of good medical care tends to vary inversely with the need for it in the population served “Agentic” interventions, which require mobilisation of an individual's resources, whether material or psychological, generally favour those with more resources, thus tending to increase social inequalities Inequalities have also been reported in the screening and detection of cancer as well as CVD. For instance, women who choose to attend the National Health Service (NHS) Breast Screening Programme come more from affluent areas In the US, Frohlich's analysis likewise suggested that even when individual-based interventions are widely applied , they may increase disparities Likewise, inequalities in anti-hypertensive therapy have been reported. A recent study suggested that social and ethnic disparities in the detection and management of hypertension have persisted in the UK despite major investment in quality improvement initiatives, including pay for performance For smoking cessation, greater use and higher quit rates of cessation services by more advantaged individuals are a real concern With respect to dietary advice, US policies traditionally favour individual approaches over public health strategies. There, Kanjilal and colleagues recently reported bigger declines in CVD risk factors in more affluent groups In England, a high-risk approach to CVD prevention that specifically prioritises disadvantaged groups and localities is being actively promoted. The National Institute for Health and Clinical Excellence recently published public health guidelines advising specific approaches for identifying and supporting people most at risk of dying prematurely Might a coordinated approach that integrates population-based and high-risk approaches be more effective? The Norsjo Community Intervention Program in Sweden is an example of a model that combines population health and health sector interventions. The program created a local health promotion collaboration between healthcare providers, grocery stores, schools, and municipal authorities. Primary care physicians contacted patients for systematic risk factor screening and counselling aimed at CVD risk reduction. Community interventions included changes in food labelling to make it easier to adhere to dietary recommendations. The predicted CVD mortality risk was reduced by 36% in the intervention area compared to 1% in a control community. Socioeconomically less privileged groups benefited more from the program Socioeconomically disadvantaged populations are susceptible to under-diagnosis of hypertension, diabetes, and hypercholesterolemia and also to suboptimal care for interventions to reduce risk. Risk factor modification through tailored interventions in high-risk groups might therefore produce considerable benefits; however, evaluation is urgently required.Given the ubiquity of social and health inequalities, we should not be surprised if interventions to reduce CVD have differential effects, with advantaged groups deriving greater benefit than poorer groups. We have suggested that the potential for such unequal effects is greater for high-risk approaches, where change is contingent on action by individual patients and healthcare providers, compared with whole population approaches, where change is societal and instituted collectively by agencies with statutory responsibility for public health.Operating mainly outside the health service, the population approach offers governments the opportunity to act directly on population exposure to risk factors. It thus addresses the major drivers of health and health inequalities In conclusion, there is evidence that CVD prevention strategies for screening and treating high-risk individuals may represent a relatively ineffective approach that typically widens social inequalities. In contrast, policy interventions to limit risk-factor exposure across populations appear cheaper and more effective; they could also contribute to levelling health across socioeconomic groups. The two approaches are complementary, and Rose's advocacy of a dual strategy may prove prophetic