The status of the morbidity and the main trends in the improvement of the epidemiological surveillance of sexually transmitted infections in the city of Moscow

The present situation in sexually transmitted diseases (STD) is regarded as unfavorable. Differing tendencies in morbidity levels for various nosological forms have been established. The continuing growth of syphilis morbidity among children is considered to be specially alarming, and an increase in the number of cases of congenital syphilis is noted. The reasons of the growth of STD morbidity have not only medical, but mainly socio-economical, psychological, ethical and moral character. The main trends in the improvement of epidemiological surveillance on STD have been determined.     

An examination of factors influencing black fertility decline in the Mississippi Delta, 1880-1930

Although the fertility decline in the black population in the Mississippi Delta between the late 1870's and early 1930's closely paralleled that of the national black population, it rose much more dramatically in the 1940's and 1950's to almost 1880 levels. Given the especially rural and oppressed conditions of blacks there, the initial decline seems puzzling. Low fertility rates in the 1930's reflected a large proportion of childless females. Investigations of changing contraceptive usage and mate exposure suggest both were minor components at most. Several physiological impairments were investigated including dietary deficiences, malaria, tuberculosis, and sexually transmitted diseases (STD). Evidence suggests STD played the major role, facilitated by nutritional and other health problems. Models relying heavily on those developed by McFalls and McFalls (1984) suggest 50-80 percent of the decline could have been due to the spread of STD. Age-specific birth rates for different periods and post-World-War-II fertility increases seem consistent with this finding.     

An examination of factors influencing black fertility decline in the Mississippi Delta, 1880–1930

Abstract

Although the fertility decline in the black population in the Mississippi Delta between the late 1870's and early 1930's closely paralleled that of the national black population, it rose much more dramatically in the 1940's and 1950's to almost 1880 levels. Given the especially rural and oppressed conditions of blacks there, the initial decline seems puzzling. Low fertility rates in the 1930's reflected a large proportion of childless females. Investigations of changing contraceptive usage and mate exposure suggest both were minor components at most. Several physiological impairments were investigated including dietary deficiences, malaria, tuberculosis, and sexually transmitted diseases (STD). Evidence suggests STD played the major role, facilitated by nutritional and other health problems. Models relying heavily on those developed by McFalls and McFalls (1984) suggest 50–80 percent of the decline could have been due to the spread of STD. Age‐specific birth rates for different periods and post‐World‐War‐II fertility increases seem consistent with this finding.     

N-type inactivation of the potassium channel KcsA by the Shaker B "ball" peptide: mapping the inactivating peptide-binding epitope

The effects of the inactivating peptide from the eukaryotic Shaker BK(+) channel (the ShB peptide) on the prokaryotic KcsA channel have been studied using patch clamp methods. The data show that the peptide induces rapid, N-type inactivation in KcsA through a process that includes functional uncoupling of channel gating. We have also employed saturation transfer difference (STD) NMR methods to map the molecular interactions between the inactivating peptide and its channel target. The results indicate that binding of the ShB peptide to KcsA involves the ortho and meta protons of Tyr(8), which exhibit the strongest STD effects; the C4H in the imidazole ring of His(16); the methyl protons of Val(4), Leu(7), and Leu(10) and the side chain amine protons of one, if not both, the Lys(18) and Lys(19) residues. When a noninactivating ShB-L7E mutant is used in the studies, binding to KcsA is still observed but involves different amino acids. Thus, the strongest STD effects are now seen on the methyl protons of Val(4) and Leu(10), whereas His(16) seems similarly affected as before. Conversely, STD effects on Tyr(8) are strongly diminished, and those on Lys(18) and/or Lys(19) are abolished. Additionally, Fourier transform infrared spectroscopy of KcsA in presence of (13)C-labeled peptide derivatives suggests that the ShB peptide, but not the ShB-L7E mutant, adopts a beta-hairpin structure when bound to the KcsA channel. Indeed, docking such a beta-hairpin structure into an open pore model for K(+) channels to simulate the inactivating peptide/channel complex predicts interactions well in agreement with the experimental observations.     

The evolution of risky behaviour in the presence of a sexually transmitted disease

Sexually transmitted diseases (STDs) are widespread in nature, often sterilizing their hosts or causing other pathogenic effects. Despite this, there is a widespread occurrence of behaviours that are likely to increase the risk to an individual of contracting an STD. Here, we examine the evolution of behaviours such as promiscuity or mate choice that increase the risk of contracting an STD, but also provide a fitness benefit. As might be expected, the balance between risk and fitness benefit defines the optimal strategy, but this relationship is not straightforward. In particular, we often predict the coexistence of highly risky and highly risk-averse individuals. Surprisingly, very safe strategists that only suffer a small cost will tend to coexist with highly risky strategists rather than outcompete them as might have been expected. Rather than selecting for monogamy or for reduced mate choice, therefore, the presence of an STD may often lead to variability in either promiscuity or mate choice.     

Selective detection of abrupt input changes by integration of spike-frequency adaptation and synaptic depression in a computational network model.

Short-term synaptic depression (STD) and spike-frequency adaptation (SFA) are two basic physiological cortical mechanisms for reducing the system's excitability under repetitive stimulation. The computational implications of each one of these mechanisms on information processing have been studied in detail, but not so the dynamics arising from their combination in a realistic biological scenario. We show here, both experimentally with intracellular recordings from cortical slices of the ferret and computationally using a biologically realistic model of a feedforward cortical network, that STD combined with presynaptic SFA results in the resensitization of cortical synaptic efficacies in the course of sustained stimulation. This fundamental effect is then shown in the computational model to have important implications for the network response to time-varying inputs. The main findings are: (1) the addition of SFA to the model endowed with STD improves the network sensitivity to the degree of synchrony in the incoming inputs; (2) presynaptic SFA, whether slow or fast, combined with STD results in postsynaptic neurons responding briskly to abrupt changes in the presynaptic input current and ignoring sustained stimulation, much more effectively than either SFA or STD alone; (3) for slow presynaptic SFA postsynaptic responses to strong inputs decrease inversely to the input, whereas for weak input current to presynaptic neurons transient postsynaptic responses are strongly facilitated, thus enhancing the system's sensitivity for subtle changes in weak presynaptic inputs. Taken together, these results suggest that in systems designed to respond to temporal aspects of the input, SFA and STD might constitute two necessary, linked elements whose simultaneous interplay is important for the performance of the system.     

Structure and genetic complexity of the genomes of herpesvirus defective-interfering particles associated with oncogenic transformation and persistent infection.

The complexity and structural organization of defective-interfering (DI) particle DNA of equine herpesvirus type 1 (EHV-1) have been elucidated by using restriction enzyme and Southern blot hybridization analyses. DI particles were generated by serial high-multiplicity passage of EHV-1 in L-M cells, and total viral DNA was extracted from virus purified from supernatants of these serial passages. EHV-1 DI particle DNA was quantitatively separated from standard (STD) DNA by several cycles of CsCl isopycnic banding in a vertical rotor. Restriction endonuclease digestion profiles of pure DI DNA were completely different from the mapped patterns observed for EHV-1 STD DNA. Digestion of pure defective DNA with restriction enzymes (Bg/II, EcoRI, and XbaI), for which there are few or no cleavage sites within the S (short) region of the EHV-1 STD genome, yielded high-molecular-weight supermolar DNA bands, suggesting that a large subgenomic repeat unit was present in defective DNA. DNA blot hybridization analysis with the Bg/II supermolar fragment of defective DNA, intact DI particle genomic DNA, and EHV-1 STD DNA restriction enzyme fragments as 32P-labeled probes indicated that the EHV-1 DI particle genome originates predominately from the STD DNA S region (0.77 to 1.00 map units) and to a lesser extent from the left terminus of the unique long (UL) region (0.00 to 0.05 map units). None of the EHV-1 DNA sequences associated to date with EHV-1 oncogenesis (0.32 to 0.38 map units; O'Callaghan et al. in B. Roizman [ed.], Herpesviruses, in press; Robinson et al., Cell 32:204-219, 1983, and Proc. Natl. Acad. Sci., U.S.A., 78:6684-6688, 1981) were detected in the DI particle DNA. The importance of these data with regard to DNA replication of DI particles and the role of DI particles in one model system of EHV-1 oncogenic transformation are discussed.     

Mixed urogenital infection in men

High occurrence of sexually transmitted diseases (STD) caused by a combination of different infective agents was established. In 62.5% of cases such diseases took a course typical for mixed infections. Combinations of infective agents of STD were found to have several typical associations, e.g. Ureaplasma urealyticum and Mycoplasma hominis in combination with opportunistic microflora. The microbiocenosis of the reproductive tract was shown to form under the influence of a complex of endogenous (natural biological) and exogenous (sexual behavioral) factors leading, in each particular case, to the formation of stable associations.     

High dietary intake of medium-chain fatty acids during pregnancy in rats prevents later-life obesity in their offspring

We investigated the effects of dietary fatty acids of different chain lengths during pregnancy in the rat on the susceptibility of offspring to later-life obesity and the underlying mechanisms. Pregnant rats were fed three different diets: standard (STD), high medium-chain fatty acids (MCFA); and high long-chain fatty acids (LCFA). The male offspring were assigned to three groups: STD control, MCFA and LCFA according to the maternal diets and suckled by dams fed with STD during pregnancy and lactation. After weaning, the offspring were fed with STD from 3 to 8 weeks of age. At the age of 8 weeks, rats in three groups: high-fat diet (HFD) control, MCFA and LCFA were fed with HFD until 14 weeks of age in an attempt to induce obesity, and rats in the HFD control group were selected randomly from the STD control group. Body weight and body fat content were decreased in the MCFA group accompanied by down-regulated mRNA expression of fatty acid synthase and acetyl-coA carboxylase 1, and increased mRNA and protein expression of adenosine monophosphate (AMP)-activated protein kinase (AMPK), carnitine palmitoyltransferase 1 and uncoupling protein 3 compared with the corresponding controls at 3, 8 and 14 weeks of age. The results suggested that the MCFA diet during pregnancy prevented later-life obesity in the offspring when they were exposed to HFD in later life, which might be related to programming of the expression of genes involved in fatty acid metabolism.     

Implication of synaptotagmins 4 and 7 in activity-dependent somatodendritic dopamine release in the ventral midbrain

Dopamine (DA) neurons can release DA not just from axon terminals, but also from their somatodendritic (STD) compartment through a mechanism that is still incompletely understood. Using voltammetry in mouse mesencephalic brain slices, we find that STD DA release has low capacity and shows a calcium sensitivity that is comparable to that of axonal release. We find that the molecular mechanism of STD DA release differs from axonal release with regard to the implication of synaptotagmin (Syt) calcium sensors. While individual constitutive knockout of Syt4 or Syt7 is not sufficient to reduce STD DA release, the removal of both isoforms reduces this release by approximately 50%, leaving axonal release unimpaired. Our work unveils clear differences in the mechanisms of STD and axonal DA release.     

江西大岗山地区7-9月降水量的重建与分析

根据江西大岗山地区4个采样点的马尾松年轮样本,建立了本地区的综合年轮年表,分析了马尾松径向生长与气候因子变化的相关及响应关系,发现大岗山地区树木径向生长受生长季7—9月降水量影响较显著,呈负相关关系。在响应分析的基础上,首次重建了大岗山地区1892年以来7—9月的降水量,交叉检验表明重建序列是可靠的。重建结果表明,大岗山地区7—9月份降水变化在过去的117年中总体经历了3个偏干时期：1895—1902年,1908—1926年和1944—1985年,和3个偏湿阶段：1903—1907年,1927—1943年及1986—2008年。重建的降水量序列在1921年,1937年及1977年发生明显的方差突变,表明百年以来该地区降水量变化趋势存在阶段性变化。     

Mutations in the MESP2 gene cause spondylothoracic dysostosis/Jarcho-Levin syndrome

Spondylothoracic dysostosis (STD), also known as Jarcho-Levin syndrome (JLS), is an autosomal-recessive disorder characterized by abnormal vertebral segmentation and defects affecting spine formation, with complete bilateral fusion of the ribs at the costovertebral junction producing a "crab-like" configuration of the thorax. The shortened spine and trunk can severely affect respiratory function during early childhood. The condition is prevalent in the Puerto Rican population, although it is a panethnic disorder. By sequencing a set of candidate genes involved in mouse segmentation, we identified a recessive E103X nonsense mutation in the mesoderm posterior 2 homolog (MESP2) gene in a patient, of Puerto Rican origin and from the Boston area, who had been diagnosed with STD/JLS. We then analyzed 12 Puerto Rican families with STD probands for the MESP2 E103X mutation. Ten patients were homozygous for the E103X mutation, three patients were compound heterozygous for a second nonsense mutation, E230X, or a missense mutation, L125V, which affects a conserved leucine residue within the bHLH region. Thus, all affected probands harbored the E103X mutation. Our findings suggest a founder-effect mutation in the MESP2 gene as a major cause of the classical Puerto Rican form of STD/JLS.     

Aging effects on posture-related modulation of stretch reflex excitability in the ankle muscles in humans

The purpose of this study was to examine the effects of aging on posture-related changes of the stretch reflex excitability in the ankle extensor, soleus (SOL), and flexor, tibialis anterior (TA) muscles. Fourteen neurologically normal elderly (mean 68 ± 6 years) and 12 young (mean 27 ± 3 years) subjects participated. Under two postural conditions, upright standing (STD) and sitting (SIT), stretch reflex electromyographic (EMG) responses in the SOL/TA muscle were elicited by imposing rapid ankle dorsi-/plantar-flexion. Under the SIT condition, subjects were asked to keep the SOL background EMG level, which is identical to that under the STD condition. In the SOL muscle, both groups showed significant enhancement of the short-latency stretch reflex (SLR) response when the posture changed from SIT to STD. In the TA muscle, the young group showed significant enhancement of the middle- (MLR) and long-latency stretch reflex (LLR) when the posture changed from SIT to STD; no such modulation was observed in the elderly group. Since the TA stretch reflex responses under the STD condition were comparable in the young and elderly groups, the lack of posture-related modulation of the TA muscle in the elderly group might be explained by augmented stretch reflex excitability under the SIT condition. The present results suggest that the (1) SOL SLR responses are modulated both in the young and elderly subjects when the posture is changed from SIT to STD, (2) TA MLR and LLR responses are not modulated in the elderly subjects when the posture is changed from SIT to STD, while each response is same between the young and elderly in STD, and (3) the effect of aging on the posture-related stretch reflex differs in the SOL and TA muscles.     

Mating Competition,Promiscuity, and Life History Traits as Predictors of Sexually Transmitted Disease Risk in Primates

Competition among males influences the distribution of copulations and should therefore influence the spread of sexually transmitted diseases (STDs). We developed a model to investigate STDs in the mating and social systems found in primates, and we tested predictions using comparative methods. In the model, groups were distributed on a square lattice in which males or females disperse and males undergo characteristic dominance trajectories at maturity (challenge vs. queuing). We investigated the impact of mating rate, mating skew, migration rate of males or females, and group size on disease spread and prevalence. The model generated several predictions: 1) STD prevalence is higher in females than males; 2) STD risk increases with copulation rate; 3) high skew is negatively associated with STD risk; 4) STD risk is higher for all individuals when females disperse and 5) when mortality rates are lower; and 6) reproductive skew and later age of male dominance (queuing) produce more strongly female-biased STD prevalence. In comparative tests, we quantified STD risk as prevalence and richness of sexually transmitted organisms at the host species level. We found positive associations between host longevity and higher STD richness, and only (nonsignificant) weak trends for females to have higher STD prevalence. Mating skew showed a weakly positive association with STD richness, contrary to predictions of our model but consistent with predictions from a previous model. In some tests, we also found that female dispersal resulted in greater STD infection risk. Collectively, these results demonstrate that mating competition and demography influence patterns of STD infection, with mortality rates having the strongest effects in comparative tests.     

Somatodendritic dopamine release requires synaptotagmin 4 and 7 and the participation of voltage-gated calcium channels

Somatodendritic (STD) dopamine (DA) release is a key mechanism for the autoregulatory control of DA release in the brain. However, its molecular mechanism remains undetermined. We tested the hypothesis that differential expression of synaptotagmin (Syt) isoforms explains some of the differential properties of terminal and STD DA release. Down-regulation of the dendritically expressed Syt4 and Syt7 severely reduced STD DA release, whereas terminal release required Syt1. Moreover, we found that although mobilization of intracellular Ca(2+) stores is inefficient, Ca(2+) influx through N- and P/Q-type voltage-gated channels is critical to trigger STD DA release. Our findings provide an explanation for the differential Ca(2+) requirement of terminal and STD DA release. In addition, we propose that not all sources of intracellular Ca(2+) are equally efficient to trigger this release mechanism. Our findings have implications for a better understanding of a fundamental cell biological process mediating transcellular signaling in a system critical for diseases such as Parkinson disease.     

The Characteristics of Heterosexual STD Clinic Attendees Who Practice Oral Sex in Zhejiang Province,China

Background

The characteristics of heterosexual attendees who visit sexually transmitted disease (STD) clinics and practice oral sex have not been revealed in China. This information is important for the development of targeted STD prevention programmes for this population.

Study Design

A self-administered questionnaire survey with a cross-sectional design was administered to consecutive attendees at four STD clinics in Zhejiang Province, China, between October and December in 2007. Demographic, psychosocial, and behavioural factors associated with oral sex over a lifetime were identified using univariate and multivariate analyses.

Results

Of the 872 attendees, 6.9% engaged in oral sex over their lifetimes. Of the oral-sex group, 96.6% also engaged in vaginal sex. The correlates for oral sex over a lifetime as determined by the multivariate analysis were high income (odds ratio [OR] = 2.53, 95% confidence interval [CI] 1.39–4.59), high human immunodeficiency virus (HIV)-related knowledge (OR = 2.71, 95% CI 1.26–5.81), early sex initiation (OR = 2.42, 95% CI 1.37–4.27), multiple sexual partners (OR = 3.09, 95% CI 1.58–6.06), and sexually active in the previous 6 months (OR = 7.73, 95% CI 1.04–57.39).

Conclusions

Though the prevalence of oral sex is low, the heterosexual STD clinic attendees practicing oral sex was found to have higher risks associated with STD/HIV transmission than those not. Behavioural and medical interventions conducted by clinicians in Chinese STD clinics should take into account the characteristics and related risks of those who practice oral sex.     

Effects of genital tract inflammation on human immunodeficiency virus type 1 V3 populations in blood and semen

We have examined cell-free viral populations in the blood plasma and seminal plasma compartments of men infected with subtype C human immunodeficiency virus type 1 (HIV-1) using the V3-specific heteroduplex tracking assay (V3-HTA). We studied two cohorts of subjects who had visited either a sexually transmitted disease (STD) clinic for genital tract inflammation in the form of urethritis (n = 43) or a dermatology clinic (controls, n = 14) in Malawi. We have previously shown that the presence of urethritis is associated with an eightfold increase in virus load in the seminal plasma compartment (M. S. Cohen et al., Lancet 349:1868-1873, 1997). The purpose of this study was to determine whether genital tract inflammation and its treatment caused genetic instability in cell-free HIV-1 populations. In a cross-sectional analysis at study entry, three-fourths of the STD and control subjects had multiple V3 populations in their blood while 60% of the STD subjects and 79% of the control subjects had multiple V3 populations in their semen. Overall, one-fourth of all of the subjects showed discordance between results with blood and semen specimens when samples were compared for the presence and absence of subpopulations. When differences in the relative levels of abundance of bands were also taken into account, two-fifths of all of the subjects showed discordance between the compartments. Among the subset of subjects in whom multiple virus populations could be detected, half showed discordance between the compartments. There were no differences between STD and control cohorts for these comparisons of the compartments in this cross-sectional analysis at study entry. Longitudinal analysis of the viral populations from two separate clinic visits over 1 to 4 weeks showed that the complexity of each V3 population as measured by Shannon entropy was different in blood and semen at the two time points, indicating that the blood and semen constitute different compartments for HIV-1. The seminal plasma compartment was more dynamic than the blood plasma compartment for the STD subjects who were treated for urethritis, with changes being noted in the presence or absence of V3-HTA bands in the semen of 29% of these subjects but in the blood of only 9% of these subjects. However, the changes were generally small. Overall, our results suggest that 40% of male subjects show discordance between seminal and blood viral populations and that the complexity of each V3 population was different between the two compartments. Both of these results point to the partial independence of the seminal compartment as a viral niche within the body.     

Design of a "microbicide" for prevention of sexually transmitted diseases using "inactive" pharmaceutical excipients.

The human immunodeficiency virus (HIV-1) pandemic has been driven primarily by the sexual transmission of the virus, and facilitated by prior infections with other sexually transmitted disease (STD) pathogens. Although treatment of these STDs has been proposed as a means to decrease the rate of HIV-1 sexual transmission, preventive measures effective against both HIV-1 and other STD pathogens are expected to have a larger impact. These measures include topically applied mechanical and chemical (i.e. microbicidal) barriers. Microbicides of preference should have a broad specificity against diverse STD pathogens and a well established safety record, considering their repeated use over decades. Here, we report that cellulose acetate phthalate (CAP), an "inactive" pharmaceutical excipient, commonly used in the production of enteric tablets and capsules: (1) has antiviral activity against HIV-1 and several herpesviruses (HSV); and (2) when appropriately formulated, in micronized form, inactivates HIV-1, HSV-1, HSV-2, cytomegalovirus, Neisseria gonorrhoeae, Trichomonas vaginalis, Haemophilus ducreyi and Chlamydia trachomatis but does not affect Lactobacilli, components of the natural vaginal flora contributing to resistance against STDs. Thus, the CAP formulations meet the criteria for preferred microbicides and warrant further evaluation in vivo in humans.     

Daily short-period gravitation can prevent functional and structural changes in arteries of simulated microgravity rats.

This study was designed to clarify whether simulated microgravity-induced differential adaptational changes in cerebral and hindlimb arteries could be prevented by daily short-period restoration of the normal distribution of transmural pressure across arterial vasculature by either dorsoventral or footward gravitational loading. Tail suspension (Sus) for 28 days was used to simulate cardiovascular deconditioning due to microgravity. Daily standing (STD) for 1, 2, or 4 h, or +45 degrees head-up tilt (HUT) for 2 or 4 h was used to provide short-period dorsoventral or footward gravitational loading as countermeasure. Functional studies showed that Sus alone induced an enhancement and depression in vasoconstrictor responsiveness of basilar and femoral arterial rings, respectively, as previously reported. These differential functional alterations can be prevented by either of the two kinds of daily gravitational loading treatments. Surprisingly, daily STD for as short as 1 h was sufficient to prevent the differential functional changes that might occur due to Sus alone. In morphological studies, the effectiveness of daily 4-h HUT or 1-h STD in preventing the differential remodeling changes in the structure of basilar and anterior tibial arteries induced by Sus alone was examined by histomorphometry. The results showed that both the hypertrophic and atrophic changes that might occur, respectively, in cerebral and hindlimb arteries due to Sus alone were prevented not only by daily HUT for 4 h but also by daily STD even for 1 h. These data indicate that daily gravitational loading by STD for as short as 1 h is sufficient to prevent differential adaptational changes in function and structure of vessels in different anatomic regions induced by a medium-term simulated microgravity.