Is the ApoE polymorphism associated with dilated cardiomyopathy?

Apolipoprotein E (ApoE) is 34 kDa protein involved in the modulation of cholesterol transport and homeostasis. Polymorphism of the ApoE gene has been implicated in many chronic cardiovascular and neuronal diseases. ApoE epsilon4 allele has been reported to be associated with increased risk of cardiovascular diseases such as myocardial infarction, hypertension, coronary heart disease, etc. Fifty patients with the end-stage dilated cardiomyopathy (DCM) and advanced congestive heart failure were examined in our study. For evaluation of ApoE polymorphism, novel approach of fast screening of ApoE gene polymorphism by combination of PCR and blotting (CVD StripAssay) was used. Individual genotypes were correlated with basic cardiologic clinical parameters. The reported frequency of this allele in Caucasian population is 14.7 %. Our results showed that in patients with DCM frequency of the ApoE epsilon4 allele is 40 %. Frequency of the genotype epsilon2/4 was 58 % and epsilon3/4 was 22 %. Comparison with control Caucasian groups monitored by others clearly revealed that frequency of epsilon4 alelle is increased in patients with advanced stages of DCM. This observation suggests association of ApoE polymorphism with severe form of DCM. Physiological consequences of this observation remain to be clarified.     

Is Acanthamoeba pathogenicity associated with intracellular bacteria?

In addition to the possible role of Acanthamoeba as an evolutionary precursor of pathogenicity in microbial pathogens, it has been suggested that intracellular bacteria or other microbial endosymbionts may also enhance the pathogenicity of Acanthamoeba. Using transmission electron microscopy, polymerase chain reaction and simple culturing, our findings did not reveal any apparent evidence of microbial presence intracellularly of a recently recovered clinical isolate of Acanthamoeba. Based on these findings, it is tempting to speculate that the virulence of Acanthamoeba may not be attributed to the pathogenicity of the endosymbiont alone.     

Is the shift in chronotype associated with an alteration in well-being?

The study aimed to test whether a shift in chronotype (determined by mid-sleep on free days) is associated with alterations in psychological well-being and sleep parameters. One hundred and seventeen undergraduates were tested in longitudinal study with four repeated measures. Measurements were taken during spring in three-week intervals and each measurement consisted of self-reported sleep parameters on work and free days (i.e. bedtime, sleep latency, wake time, sleep onset, mid-sleep time, social jetlag), satisfaction with life, and mood (energetic arousal, tense arousal, hedonic tone). Between-subjects analyses revealed earlier chronotypes, as compared to the later ones, showing lower tense arousal, higher energetic arousal and life satisfaction, earlier bedtime, sleep onset and offset on both work and free days, longer sleep duration and shorter sleep latency on workdays, and less social jetlag. Within-subjects analyses revealed increasing photoperiod associated with a shift toward earlier chronotype, decrease in social jetlag, and shortening sleep latency. The seasonal shift toward earlier chronotype was not associated with alterations in mood or life satisfaction, but it was associated with a shift toward earlier bedtimes and longer sleep duration on workdays, decrease in sleep latency, and social jetlag. Results from the within-subjects analyses were consistent with the results of between-subjects analyses regarding sleep–wake functioning, but inconsistent regarding psychological outcomes.     

Is replenishment of the readily releasable pool associated with vesicular movement?

At the excitatory synapse of rat hippocampus the short-term synaptic depression observed during long high-frequency stimulation is associated with slower replenishment of the readily-releasable pool. Given that the replenishment rate is also not [Ca⁺⁺]_o sensitive this puts into question a widely held notion that the vesicles—constrained by the cytoskeleton and rendered free from such constraints by Ca⁺⁺ entry that renders them more mobile—are important in the replenishment of the readily-releasable pool. This raises a question—Is vesicular replenishment of the readily releasable pool associated with significant movement? To answer this question we evaluated how okadaic acid and staurosporine (compounds known to affect vesicular mobility) influence the replenishment rate. We used patterned stimulation on the Schaffer collateral fiber pathway and recorded the excitatory post-synaptic currents (EPSCs) from rat CA1 neurons, in the absence and presence of these drugs. The parameters of a circuit model with two vesicular pools were estimated by minimizing the squared difference between the ESPC amplitudes and simulated model output. [Ca²⁺]_o did not influence the progressive decrease of the replenishment rate during long, high frequency stimulation. Okadaic acid did not significantly affect any parameters of the vesicular storage and release system, including the replenishment rate. Staurosporine reduced the replenishment coupling, but not the replenishment rate, and this is owing to the fact that it also reduces the ability of the readily releasable pool to contain quanta. Moreover, these compounds were ineffective in influencing how the replenishment rate decreases during long, high frequency stimulation. In conclusion at the excitatory synapses of rat hippocampus the replenishment of the readily releasable pool does not appear to be associated with a significant vesicular movement, and during long high frequency stimulation [Ca⁺⁺]_o does not influence the progressive decrease of vesicular replenishment.     

Is there a mucosal immune system associated with the mammalian oviduct?

The oviduct is a key component of the reproductive system where essential states such as spermatozoa capacitation, fertilization and early embryo development take place. Recently, an additional role for the entire female reproductive tract has emerged with important implications for our understanding and management of reproductive health, namely, its role in mounting local immune responses against microbial pathogens. Most of the evidence about mucosal immune responses in the female reproductive tract is related to the vagina, with less information available for the uterus. The less known segment in this regard is the oviduct, which prompted us to review and summarize the current state of knowledge on the immune system at the level of the mammalian oviduct. A comprehensive search was conducted in Medline and--for the last two years--also in Current Contents. Result demonstrate that the mammalian oviduct is endowed with many of the elements that characterize a mucosal immune system. However, there are gaps in our knowledge that, in addition to important interspecies differences, make it essential to explore further some fundamental questions regarding this system.     

Is interleukin-18 associated with polycystic ovary syndrome?

Background  

Recent research show that polycystic ovary syndrome (PCOS) may have an association with low-grade chronic inflammation, IL-18 is considered as a strong risk marker of inflammation.     

Is dynamic thiol/disulfide homeostasis associated with the prognosis of myelodysplastic syndrome?

BackgroundThis study planned to investigate the relationship of dynamic thiol/disulfide homeostasis with the prognosis of myelodysplastic syndrome (MDS).Methods80 patients who had been diagnosed with MDS between 2012 and 2017 and who were older than 18 were included in the study together with 80 healthy control subjects. The MDS diagnosis was confirmed using bone marrow aspiration-biopsy immunostaining. Dynamic thiol/disulfide homeostasis and ischemia-modified albumin (IMA) levels were examined.ResultsThe average IMA (0.71±0.08 vs. 0.67±0.09; p=0.002), median disulfide (18.0 vs. 11.6; p<0.001), median disulfide/native thiol (6 vs. 3; p<0.001), and median disulfide/total thiol (5.4 vs. 2.9; p<0.001) were found higher in the MDS patients compared to control group, and the median hemoglobin, median white blood cell count, median neutrophil count, median lymphocyte count, average native thiol (290.7±48.5 vs. 371.5±103.8; p<0.001), average total thiol (328.2±48.9 vs. 393±105.5; p<0.001), and average native thiol/total thiol (%) (88.3±4.3 vs. 94.2±2.1; p<0.001) were found to below. Risk factors such as collagen tissue disease (HR:9.17; p=0.005), MDS-EB-1 (HR:10.14; p=0.032), MDS-EB-2 (HR:18.2; p=0.043), and disulfide/native thiol (HR:1.17; p=0.023) were found as the independent predictors anticipating progression to acute myeloid leukemia. In the Cox regression model, risk factors such as age (HR:1.05; p=0.002), MDS-EB-1 (HR:12.58; p<0.001), MDS-EB-2 (HR:5.75; p=0.033), disulfide/native thiol (HR:1.14; p=0.040), and hemoglobin (HR:0.64; p=0.007) were found as predictors anticipating for mortality.ConclusionsWe can argue that dynamic thiol/disulfide homeostasis could have significant effects on both the etiopathogenesis and the survival of patients with MDS, and it could be included in new prognostic scoring systems.     

Is herpes simplex virus associated with peptic ulcer disease?

To test the hypothesis that herpes simplex virus type 1 (HSV-1) may be associated with peptic ulcer disease, we examined ulcerative lesions of the distal stomach and proximal duodenum for the presence of nucleic acids and antibodies specific for HSV-1. Utilizing in situ hybridization, immunocytochemistry, and polymerase chain reaction with sequencing, gastric or duodenal tissues from 4 of 22 patients (18%) with documented peptic ulcer disease demonstrated the presence of both specific HSV-1 nucleic acid sequences and proteins. HSV-1 was found restricted in clusters of cells near the margin of the ulcer but was absent at sites distal to the lesion. Several of such HSV-1-infected cells also contained cholecystokinin. These cholecystokinin-containing cells are of neuroendocrine origin and receive contact from the vagal nerve. Campylobacter pylori bacteria were not found in three of the four peptic ulcer tissues that harbored HSV-1. Further, none of the stomach or duodenal tissue samples from 33 patients undergoing clinical evaluation, but having no evidence of peptic ulcer disease, had HSV-1 materials. Thus, our data suggest that a subset of peptic ulcer disease may be associated with HSV-1 and raise the possibility that some peptic ulcers may be caused by this virus.     

Is circadian type associated with sleep duration in twins?

Sleep and Biological Rhythms - We used the community-based University of Washington Twin Registry to investigate the genetic association between circadian type and sleep duration. Habitual sleep...     

Is early osteoarthritis associated with differences in joint congruence?

Previous studies suggest that osteoarthritis (OA) is related to abnormal or excessive articular contact stress. The peak pressure resulting from an applied load is determined by many factors, among which is shape and relative position and orientation of the articulating surfaces or, referring to a more common nomenclature, joint congruence. It has been hypothesized that anatomical differences may be among the causes of OA. Individuals with less congruent joints would likely develop higher peak pressure and thus would be more exposed to the risk of OA onset. The aim of this work was to determine if the congruence of the first carpometacarpal (CMC) joint differs with the early onset of OA or with sex, as the female population has a higher incidence of OA. 59 without and 38 with early OA were CT-scanned with their dominant or arthritic hand in a neutral configuration. The proposed measure of joint congruence is both shape and size dependent. The correlation of joint congruence with pathology and sex was analyzed both before and after normalization for joint size. We found a significant correlation between joint congruence and sex due to the sex-related differences in size. The observed correlation disappeared after normalization. Although joint congruence increased with size, it did not correlate significantly with the onset of early OA. Differences in joint congruence in this population may not be a primary cause of OA onset or predisposition, at least for the CMC joint.     

Is facial width-to-height ratio reliably associated with social inferences?

Theoretical considerations and early empirical findings suggested facial width-to-height ratio (fWHR) may be relevant to person perception because it is associated with behavioral dispositions. More recent evidence failing to find fWHR-behavior links suggests that mismatch or byproduct hypotheses may be necessary to explain fWHR-based trait inferences; however, these explanations may not be needed because it is not clear that fWHR is reliably associated with trait inferences. To investigate the robustness of fWHR-inference links, we conducted secondary analyses of a cross-national dataset consisting of ratings by 11,481 participants across 11 world regions who judged 60 male and 60 female faces on one of 13 social traits (ns per trait range from 760 to 975). In preregistered analyses—and exploratory analyses of a subset of traits in the larger sample of 597 faces from which the 120 faces were drawn—we found mixed evidence for fWHR-based social judgments. In multilevel models, fWHR was not reliably linked to raters' judgments of male faces for any of the 13 trait-inferences but was negatively associated with ratings of female faces' dominance, trustworthiness, sociability, emotional stability, responsibility, confidence, attractiveness, and intelligence. In exploratory analyses of a subset of traits using the larger sample of faces, fWHR was associated positively with perceptions of meanness and aggressiveness in male but not female faces, negatively with attractiveness and dominance in female but not male faces, and negatively with trustworthiness in male but not female faces. We interpret these mixed findings to suggest that (1) fWHR-inference links are likely to be smaller and less reliable than expected from prior research; (2) fWHR may play a larger role in perceptions of female faces than would be predicted from the theory underpinning fWHR hypotheses; and (3) future research should more closely examine the extent to which robust fWHR-inferences reflect mismatch in the reliability of fWHR-behavior links between ancestral and modern environments versus byproducts of other person perception mechanisms.     

Is catalase activity one of the factors associated with maize resistance to Aspergillus flavus?

Plant responses to biotic and abiotic stresses are usually accompanied by the release of reactive oxygen species including hydrogen peroxide. Hydrogen peroxide plays a direct role in defense and is involved in many signal transduction pathways that lead to the proliferation of other defenses. Because catalase helps to maintain reactive oxygen homeostasis during biotic and abiotic stress, its activity was measured in various cob tissues during maize ear development. Catalase activity was determined in immature and mature embryos, pericarp, and rachis tissues of maize lines that are resistant and susceptible to Aspergillus flavus infection. The effect of fungal inoculation on catalase activity was also measured. Over two years of field experimentation, a correlation was observed between resistance and the level of catalase-specific activity in immature embryos, which was significantly higher in resistant lines (P < 0.0001). Furthermore, catalase activity in the resistant lines was significantly higher in immature embryos from inoculated ears (P = 0.0199). No correlation was observed between resistance and catalase activity in other ear tissues. Levels of hydrogen peroxide, the catalase substrate, and salicylic acid in the embryo were also determined. The resistant lines showed lower levels of H2O2 (P < 0.0001) and higher levels of salicylic acid (P < 0.0001) as compared with the susceptible lines. Catalase 3 was sequenced from the aflatoxin-resistant (Mp313E) and susceptible (SC212m) inbreds. The predicted amino acid sequence indicated that there was a 20-aa deletion in the resistant inbred that might affect enzymatic activity. Unlike many plant-pathogen interactions, it appears that lowering H2O2 levels helps to prevent A. flavus infection and subsequent aflatoxin accumulation.     

Is the United States Still Dominant in the Global Pharmaceutical Innovation Network?

The dramatic growth of research and development activities in the pharmaceutical sector in emerging economies raises the question of whether the United States still keeps its dominant role in the global pharmaceutical innovation landscape. This paper focuses on investigating the role of the United States in global pharmaceutical innovation, and differs from previous studies by shifting attention to a network analytic perspective to track the global distribution of pharmaceutical inventions. Our sample is composed of key patents covering all new drugs approved by the Food and Drug Administration between 1996 and 2010. The results show that the United States still dominates in the global pharmaceutical innovation network, especially when it comes to essential core inventions. However, the United States shows a slightly decreasing prominence in the networks of either total new drugs or New Molecular Entity (NME) drugs in the time period 2006–2010 as compared to previous time periods, revealed by subtle traces of network centralities.     

Is mating of copepods associated with increased risk of predation?

In laboratory experiments, we tested whether the cyclopoid copepodCyclops vicinus is more vulnerable to predation by juvenile(young-of-the-year) roach (Rutilus rutilus) and/or larvae ofthe phantom midge Chaoborus flavicans during mating than individualadult copepods of the same species. We also tested whether C.vicinusavoided mating, displayed shorter mating times and/or loweractivity when a predator (Chaoborus) was present, or when exposedto water in which predators (Chaoborus) were previously held.Fish ate the same quantity of pairs in copulation and individualegg-bearing females but significantly fewer females withouteggs. Chaoborus ate similar quantities of pairs and femalesbut fewer males. Pairs in copulation and egg-bearing femaleswere detected earlier by fish than individual non-ovigerousfemales or males, and pairs in copulation were captured mosteasily by fish. Cyclops vicinus mated less often when Chaoboruslarvae were present than in water in which Chaoborus was previouslyheld, or in pure tap water. However, predator presence or exposureto predator-treated water had no effect on (i.e. did not reduce)mating duration. Activity of C.vicinus pairs during copulationwas significantly lower when a predator was present, or in predator-treatedwater, than in pure tap water, and activity of pairs decreasedwith increasing activity of the predator. Although our experimentswere carried out under artificial conditions which cannot betransferred to the complex conditions in the field, they suggestthat mating in copepods is dangerous and that copepods haveevolved particular strategies to reduce the risk of predationduring mating.     

Is sociality associated with high longevity in North American birds?

Sociality, as a life-history trait, should be associated with high longevity because complex sociality is characterized by reproductive suppression, delayed breeding, increased care and survival, and some of these traits select for high longevity. We studied the relationship between cooperative parental care (a proxy of complex sociality) and relative maximum lifespan in 257 North American bird species. After controlling for variation in maximum lifespan explained by body mass, sampling effort, latitude, mortality rate, migration distance and age at first reproduction, we found no significant effect of cooperative care on longevity in analyses of species-specific data or phylogenetically independent standardized linear contrasts. Thus, sociality itself is not associated with high longevity. Rather, longevity is correlated with increased body size, survival rate and age of first reproduction.