Wilms' tumor 1-associating protein regulates the proliferation of vascular smooth muscle cells

Smooth muscle cells (SMCs) are called on to proliferate during vascular restructuring but must return to a nonproliferative state if remodeling is to appropriately terminate. To identify mediators of the reacquisition of replicative quiescence, we undertook gene expression screening in a uniquely plastic human SMC line. As proliferating SMCs shifted to a contractile and nonproliferative state, expression of TIMP-3, Axl, and KIAA0098 decreased whereas expression of complement C1s, cathepsin B, cellular repressor of E1A-activated genes increased. Wilms' tumor 1-associating protein (WTAP), a nuclear constituent of unknown function, was also upregulated as SMCs became nonproliferative. Furthermore, WTAP in the intima of injured arteries was substantially upregulated in the late stages of repair. Introduction of WTAP complementary DNA into human SMCs inhibited their proliferation, with a corresponding decrease in DNA synthesis and an increase in apoptosis. Knocking down endogenous WTAP increased SMC proliferation, because of increased DNA synthesis and G(1)/S phase transition, together with reduced apoptosis. WTAP was found to associate with the Wilms' tumor-1 protein in human SMCs and WTAP overexpression inhibited the binding of WT1 to an oligonucleotide containing a consensus WT1 binding site, whereas WTAP knockdown accentuated this interaction. Expression of the WT1 target genes, amphiregulin and Bcl-2, was suppressed in WTAP-overexpressing SMCs and increased in WTAP-deficient SMCs. Moreover, exogenous amphiregulin rescued the antiproliferative effect of WTAP. These findings identify WTAP as a novel regulator of the cell cycle and cell survival and implicate a WTAP-WT1 axis as a novel pathway for controlling vascular SMC phenotype.     

Analysis of the epidemiological factors influencing vulpine trichinellosis in ecologically different regions of Slovakia

INTRODUCTION: In the Slovak Republic, trichinellosis circulates almost exclusively in the sylvatic cycle, with main reservoir host red fox and wild boar and sporadic occurrence of human outbreaks. A detailed study was performed in five ecologically different regions of eastern Slovakia with more profound regard to eco-geographical and anthropogenic influences to natural fox habitat. MATERIAL AND METHODS: In total of 689 red foxes (Vulpes vulpes) hunted in selected regions in 2005/2006 was examined using artificial digestion method. Larvae obtained from infected samples were on the species level characterised using multiplex PCR analysis. RESULTS: The study revealed a total prevalence of 15.6%, with most frequent occurrence of infected foxes in the mountain of the Volovské Vrchy (25.2%) where both human habitation and fox population are very dense. High prevalence rates were found in the Kosická Kotlina Basin (19.6%) with urbanised landscape, concentrated human activities and low fox population and in national park of the High Tatras (15.8%) where the inhabitants and fox population are relatively low. In the remote localities of the Nízke Beskydy Highlands that represent ideal fox habitat free of any human impact, 14.2% of foxes harboured Trichinella larvae. The lowest occurrence of infected foxes (6.9%) was found in agrarian areas of the Vychodoslovenská Nizina Lowland, with relatively low inhabitants and fox population density. In all localities Trichinella britovi was the most important etiological agent of sylvatic trichinellosis.     

Lack of association between clopidogrel responsiveness tested using point-of-care assay and prognosis of patients with coronary artery disease

Dual antiplatelet therapy is important treatment modality across the spectrum of coronary artery disease manifestations. However, a significant number of patients do not have a completely effective response to clopidogrel. This study assessed the impact of response after clopidogrel with Verify Now device on prognosis on patients undergoing coronary interventions. Consecutive patients following percutaneous coronary intervention were prospectively enrolled. A loading dose of 600 mg of clopidogrel was administered before or during PCI. Blood samples were drawn within 24 h after clopidogrel administration. The effect of clopidogrel was measured using VerifyNow. All patients were evaluated at 6 months. The primary end-point was the combination of death, MI and stroke. 378 patients (69.3 % men and 30.7 % women) were enrolled. The mean age was 67.2 ± 12.8 years, BMI 28.9 ± 17.7, and 116 patients had diabetes (30.7 %). During the 6-months follow-up 30 patients (7.94 %) experienced a monitored end-point: 12 patients (3.17 %) had MI; five patients (1.32 %) strokes and 15 patients (3.97 %) died. The remaining 248 patients (71.26 %) were end-point free. Factors associated with a poor prognosis were: leukocytes (OR 1.7 [1.2–2.4], p < 0.01), creatinine (OR 1.4 [1.1–2.5], p < 0.05) and at a borderline level the presence of AA allele of gene CYP2C19*2 (OR 2.5 [0.99–4.1], p = 0.052). The results using VerifyNow were similar between both groups (Group End-point: 208.5 ± 85.5, group No end-point 203.1 ± 91.3) and failed to show any prognostic value (OR 1.00 [0.992–1.007], p = 0.9). The measurement of clopidogrel efficacy using VerifyNow had no prognostic value for our unselected cohort of patients after PCI.     

Difficulties of motion-onset VEP interpretation in school-age children

Background

In adults, motion-onset visual evoked potentials (M-VEPs) with a dominant N2 peak represent a useful diagnostic tool. However, it is difficult to use this type of VEP in children because of the long maturation (up to 18 years) of M-VEPs, which is characterised by a gradual decrease in N2 peak latency and shape development. Moreover, in some children, M-VEPs are difficult to identify with standard stimuli.

Methods

We tested features of M-VEPs in 30 children (7–12 years) with the following set of standard stimuli used in our lab for examining adults (https://web.lfhk.cuni.cz/elf): low-contrast translation motion (TM) and expansion/contraction motion (ExCoM) in full field and in periphery (with central 20° masked). In 16 children, a high-contrast TM was also tested.

Results

With standard (low-contrast) stimuli, a common M-VEP to TM and to ExCoM was detected in 77 and 83 % of children, respectively. The M-VEPs to ExCoM in the periphery were detected in only 43 % of children. An abnormal dominant P1 peak was found in 9 % of VEPs to TM, 12 % of VEPs to full-field ExCoM and 14 % of VEPs to peripheral ExCoM. The M-VEPs to all low-contrast stimuli displayed large inter-individual latency variability (N2 peak latency differed for more than 100 ms). High contrast (more suitable for the non-mature magnocellular pathway) shortened M-VEP latencies and improved amplitudes.

Conclusions

Our findings show that the maturation of motion perception in children is inter-individually variable, which limits the diagnostic use of M-VEPs.     

Anti‐allergic Effect of Pleuran (β‐glucan from Pleurotus ostreatus) in Children with Recurrent Respiratory Tract Infections

Recurrent respiratory tract infections (RRTIs) present a very important problem in paediatric praxis. As true immunodeficiencies are rare, one of the most important factors assumed to contribute to increased respiratory morbidity is atopy. Several preparations of natural origin have been used for the prevention of RRTIs, and some of the most effective immunomodulators are biologically active polysaccharides – e.g. ß‐glucans. In our randomised, double‐blind, placebo‐controlled study, we investigated the prevalence of atopy in a group of children with RRTIs and the potential anti‐allergic effect of pleuran (ß‐glucan isolated from Pleurotus ostreatus) on basic laboratory markers of allergic inflammation. We confirmed that atopy may be an important factor contributing to the increased respiratory morbidity in children with RRTIs. The active treatment with pleuran resulted in a significant reduction of peripheral blood eosinophilia and stabilised the levels of total IgE in serum. This was more evident in atopic subjects. Pleuran showed a potential anti‐allergic effect. This previously non‐described effect could expand the application of this natural immunomodulator also as a complementary adjuvant therapy in allergic patients. Copyright © 2013 John Wiley & Sons, Ltd.     

The import and function of diatom and plant frataxins in the mitochondrion of Trypanosoma brucei

Frataxin is a conserved mitochondrial protein, almost universally present in prokaryotes and eukaryotes, where it is implicated in Fe-S cluster assembly and several other processes. Here we show that frataxins from the diatom Thalassiosira pseudonana and the plant Arabidopsis thaliana are efficiently targeted and processed in the mitochondrion of the evolutionary distant excavate kinetoplastid flagellate Trypanosoma brucei. Moreover, both heterologous frataxins are able to rescue a lethal deficiency for T. brucei frataxin.     

A common variation in the cannabinoid 1 receptor (CNR1) gene is associated with pre-eclampsia in the Central European population

Objective

Recently it has been proposed that tightly regulated levels of endogenous cannabinoids play a fundamental role in early placental development. The aim of this study was to investigate associations of three single-nucleotide polymorphisms (SNPs) in the cannabinoid 1 receptor (CNR1) gene (rs1049353, rs12720071 and rs806368) and their inferred haplotypes with pre-eclampsia, a severe pregnancy-associated condition characterized by abnormal development and remodeling of spiral decidual arteries.

Study design

The case-control study comprised a total of 115 pre-eclamptic women and 145 healthy pregnant controls, all originating from the Central-European Czech population. Using PCR-based methods, we tested rs1049353, rs12720071 and rs806368 in the CNR1 gene and haplotypes were constructed.

Results

Statistically significant difference in genotype distributions of rs806368 (p_g < 10⁻³) was observed when comparing the cases and the controls; the cases presenting with significantly lower proportion of CC homozygotes. In multivariate modeling, the rs806368 served as a predictor for pre-eclampsia development (β = 0.15; p = 0.04). Haplotype analysis revealed presence of four common haplotypes; the CAA haplotype being less frequent in pre-eclamptic cases compared to the controls (p < 0.008). Analysis of regression models confirmed the independent prediction role of AAC haplotype for pre-eclampsia onset (β = −0.18; p = 0.03).

Conclusion

This is the first study focusing on the relationship between SNPs in the CNR1 gene and pre-eclampsia risk. Although limited by a relatively small sample size, the study indicates that rs806368 in the CNR1 gene may act as a susceptibility marker for pre-eclampsia in humans.     

Glutathione S-transferase and microsomal epoxide hydrolase gene polymorphisms and risk of chronic obstructive pulmonary disease in Slovak population

Aim

To determine the risk of chronic obstructive pulmonary disease (COPD) associated with polymorphisms in the glutathione S-transferase (GST) M1, GST T1, and microsomal epoxide hydrolase (EPHX1) genes in a cohort of Slovak population.

Methods

Two hundred and seventeen patients with the diagnosis of COPD and 160 control subjects were enrolled in the study. Blood samples were collected from all subjects and the DNA from peripheral blood lymphocytes was used for subsequent genotyping assays, using polymerase chain reaction and restriction fragment-length polymorphism methods.

Results

In an unadjusted model, an increased risk for COPD was observed in subjects with EPHX1 His113-His113 genotype (odds ratio [OR], 2.32; 95% confidence interval [CI], 1.20-4.69; P = 0.008), compared with the carriers of the Tyr113 allele. However, after the adjustments for age, sex, and smoking status, the risk was not significant (adjusted OR, 1.79; 95% CI, 0.91-3.53; P = 0.093). In a combined analysis of gene polymorphisms, the genotype combination EPHX1 His113-His113/GSTM1 null significantly increased the risk of COPD in both, unadjusted (OR, 5.08; 95% CI, 1.70-20.43; P = 0.001) and adjusted model (OR, 4.87; 95% CI, 1.57-15.13; P = 0.006).

Conclusion

Although none of the tested gene polymorphisms was significantly related to an increased risk of COPD alone, our results suggest that the homozygous exon 3 mutant variant of EPHX1 gene in the combination with GSTM1 null genotype is a significant predictor of increased susceptibility to COPD in the Slovak population. The findings of the present study emphasize the importance of detoxifying and antioxidant pathways in the pathogenesis of COPD.Chronic obstructive pulmonary disease (COPD) represents a major public health care problem worldwide due to its increasing prevalence, morbidity, and mortality (1). Generally, COPD is characterized by progressive and only partially reversible airflow limitation (2). Although cigarette smoking is the most important risk factor for COPD, only 20%-30% of chronic smokers develop severe impairment of lung function associated with COPD (3). Besides smoking, other environmental and genetic factors and gene-environment interactions influence the development of COPD (4).Severe α-1-antitrypsin deficiency is a well established genetic risk factor for COPD that has provided a basis for the protease-antiprotease hypothesis in the pathogenesis of COPD (5,6). Other candidate genes that might play a role in the development of COPD are involved in endogenous protease/antiprotease imbalance, inflammatory processes, metabolism of mutagens and carcinogens in tobacco smoke, and in mucocilliary clearance (7). Interindividual differences in the polymorphisms of enzymes metabolizing the xenobiotic substances and free radicals contained in the cigarette smoke may play a role in the individual susceptibility to the decrease in lung functions in smokers (8).Microsomal epoxide hydrolase (EPHX1) is generally considered to be a protective enzyme involved in the defense from oxidative damage (9,10). Two common polymorphic sites in the EPHX1 gene that influence the enzyme activity can be detected (11). An exon 3 thymine-to-cytosine mutation changes Tyr residue 113 to His, thus reducing the enzyme activity by about 50%. The second mutation, an adenine-to-guanine transition in exon 4 of the gene, changes His residue 139 to Arg and results in the production of EPHX1 with the activity increased by about 25% (11). The combination of these polymorphisms leads to a formation of several functional phenotypes of EPHX1. The slow metabolizing type of EPHX1 was associated with emphysema and COPD (9). In another study, an association of slow metabolizing EPHX1 phenotype with an accelerated deterioration of lung function in smokers was observed (12). In addition, several studies conducted in different populations have suggested that the EPHX1 genotype may influence individual susceptibility to COPD (9,13-15). Nevertheless, other investigators failed to confirm an association between the EPHX1 gene polymorphisms and COPD (16-18).Glutathione S-transferases (GST) play a role in the detoxification of carcinogenic compounds contained in cigarette smoke and in the antioxidant protection (19,20). Recently, the GSTM1 and the GSTT1 gene polymorphisms have been excessively studied with respect to their potential contribution to the risk of COPD (8,17,21,22). The deficiency in the activity of GSTM1 and GSTT1 enzymes is caused by the inherited homozygous absence of the GSTM1 or GSTT1 gene, respectively (ie, GSTM1 null or GSTT1 null genotype). Previously, the homozygous GSTM1 null genotype has been associated with lung cancer (23), emphysema (21), and reductions in the lung function in Caucasian smokers with non-small-cell lung cancer (22). However, another study conducted in Koreans found no differences in the frequencies of polymorphic genotypes of GSTM1 and GSTT1 genes between patients with COPD and healthy smokers (17).Since current data on the potential associations between an increased COPD risk and genes encoding the enzymes metabolizing xenobiotic substances are inconsistent, the aim of our study was to analyze the relation between COPD and gene polymorphisms of EPHX1, GSTM1, and GSTT1 genes in a sample of Slovak population.     

Social support as a predictor of perceived health status in patients with multiple sclerosis

OBJECTIVE: The main aim of this study was to investigate whether different levels of perceived social support are associated with different levels of perceived health status in multiple sclerosis (MS) patients. METHODS: Two hundred and seven MS patients (38.4+/-10.6 years, 66.2% female) completed the Short-Form-36 Health Survey (SF-36) as the measure for perceived health status, and the perceived social support scale (PSSS) as the measure for social support. Functional disability was assessed using Kurtzke's expanded disability status scale (EDSS). The contribution of EDSS and PSSS for explaining the variance in SF-36 was investigated with multiple linear regression analysis. RESULTS: Demographic variables and EDSS explained 44% of the variance of the physical health summary scale in the SF-36. Demographic variables, EDSS and PSSS from family and friends explained 24% of the variance in mental health summary scale in the SF-36. Results varied according to the multiple linear regression analyses of predictors of variance in the eight dimensions of the SF-36. CONCLUSION: PSSS from significant others was positively associated with general health dimension of perceived physical health status, while PSSS from family and friends was positively associated with perceived mental health status in MS patients. PRACTICE IMPLICATIONS: The results show the importance of supporting social ties and relationships between MS patients and others.     

Employment status and perceived health status in younger and older people with multiple sclerosis

This study explores how employment is associated with perceived physical and mental health status in people with multiple sclerosis (MS) adjusted for sociodemographic and clinical variables stratified by age. The sample consisted of 184 MS patients divided into a younger (<45 years) and an older (≥45 years) age group. Respondents underwent an interview, a neurological examination on disability [Expanded Disability Status Scale (EDSS)], and completed the Short Form-36 Health Survey. Of the respondents (mean age 40.5±6.2 years), 43.5% were employed. Significant differences between younger and older patients were found in employment, EDSS, disease duration, and five Short Form-36 Health Survey dimensions. Block-step multiple regression explained 32.4% of the variance in physical health and 14.5% in mental health in the younger group. Being employed was significantly related to good physical health, whereas EDSS diminished the effect of being employed on physical health. The most important variable for mental health was employment status in the younger group. For the older age group, 19.1% of the variance in physical health and 14.0% of the variance in mental health was explained by the studied variables. Male gender and a lower EDSS were significant explanatory variables of better physical health. Male gender significantly explained mental health in the older age group. In conclusion, employment status was an explanatory variable for physical health and mental health in the younger patients. EDSS played a significant role in physical health for all patients. A vocational rehabilitation program could prevent eventual nonemployment and improve health outcomes in older MS people.