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41.
42.
The aim of the present study was to measure zinc (Zn) and iron (Fe) concentration in human semen and superoxide dismutase (SOD) activity in seminal plasma and correlate the results with sperm quality. Semen samples were obtained from men (N = 168) undergoing routine infertility evaluation. The study design included two groups based on the ejaculate parameters. Group I (n = 39) consisted of males with normal ejaculate (normozoospermia), and group II (n = 129) consisted of males with pathological spermiogram. Seminal Zn and Fe were measured in 162 samples (group I, n = 38; group II, n = 124) and SOD activity in 149 samples (group I, n = 37; group II, n = 112). Correlations were found between SOD activity and Fe and Zn concentration, and between Fe and Zn concentration. SOD activity was negatively associated with volume of semen and positively associated with rapid progressive motility, nonprogressive motility, and concentration. Negative correlation was stated between Fe concentration and normal morphology. Mean SOD activity in seminal plasma of semen from men of group I was higher than in seminal plasma of semen from men of group II. Fe concentration was higher in teratozoospermic males than in males with normal morphology of spermatozoa in group II. Our results suggest that Fe may influence spermatozoa morphology.  相似文献   
43.
F165(1) and the pyelonephritis-associated pili (Pap) are two members of the type P family of adhesive factors that play a key role in the establishment of disease caused by extraintestinal Escherichia coli (ExPEC) strains. They are both under the control of an epigenetic and reversible switch that defines the number of fimbriated (ON) and afimbriated (OFF) cells within a clonal population. Our present study demonstrates that the high level of ON cells found during F165(1) phase variation is due to altered stability of the DNA complex formed by the leucine-responsive regulatory protein (Lrp) at its repressor binding sites 1-3; after each cell cycle, complex formation is also modulated by the local regulator FooI (homologue to PapI) which promotes the transit of Lrp towards its activator binding sites 4-6. Furthermore, we identified two nucleotides (T490, G508) surrounding the Lrp binding site 1 that are critical to maintaining a high OFF to ON switch rate during F165(1) phase variation, as well as switching Pap fimbriae towards the OFF state.  相似文献   
44.
Three novel meroterpenoids, insuetolides A-C (1-3) and four drimane sesquiterpenes, the new (E)-6-(4'-hydroxy-2'-butenoyl)-strobilactone A (4) and the known 2α, 9α, 11-trihydroxy-6-oxodrim-7-ene (5), strobilactone A (6) and (E,E)-6-(6',7'-dihydroxy-2',4'-octadienoyl)-strobilactone A (7), were isolated from the EtOAc extract of the culture medium of the marine-derived fungus Aspergillus insuetus (OY-207), which was isolated from the Mediterranean sponge Psammocinia sp. The structures of the compounds were determined by spectroscopic methods. Insuetolides A-C reveal a new carbon skeleton derived from the cyclization of farnesyl and 3, 5-dimethylorsellinic acid. Compounds 1, 6, and 7 exhibited anti-fungal activity towards Neurospora crassa with MIC values of 140, 242, and 162 μM, respectively; and compounds 3, 4, and 7 exhibited mild cytotoxicity towards MOLT-4 human leukemia cells.  相似文献   
45.

Background

Neointima forming after stent implantation consists of vascular smooth muscle cells (VSMCs) in 90%. Growth factors TGF-β1, PDGFB, EGF, bFGF and VEGF-A play an important role in VSMC proliferation and migration to the tunica intima after arterial wall injury. The aim of this paper was an analysis of functional polymorphisms in genes encoding TGF-β1, PDGFB, EGF, bFGF and VEGF-A in relation to in-stent restenosis (ISR).

Materials and Methods

265 patients with a stable coronary artery disease (SCAD) hospitalized in our center in the years 2007–2011 were included in the study. All patients underwent stent implantation at admission to the hospital and had another coronary angiography performed due to recurrence of the ailments or a positive result of the test assessing the coronary flow reserve. Angiographically significant ISR was defined as stenosis >50% in the stented coronary artery segment. The patients were divided into two groups–with angiographically significant ISR (n = 53) and without significant ISR (n = 212). Additionally, the assessment of late lumen loss (LLL) in vessel was performed. EGF rs4444903 polymorphism was genotyped using the PCR-RFLP method whilst rs1800470 (TGFB1), rs2285094 (PDGFB) rs308395 (bFGF) and rs699947 (VEGF-A) were determined using the TaqMan method.

Results

Angiographically significant ISR was significantly less frequently observed in the group of patients with the A/A genotype of rs1800470 polymorphism (TGFB1) versus patients with A/G and G/G genotypes. In the multivariable analysis, LLL was significantly lower in patients with the A/A genotype of rs1800470 (TGFB1) versus those with the A/G and G/G genotypes and higher in patients with the A/A genotype of the VEGF-A polymorphism versus the A/C and C/C genotypes. The C/C genotype of rs2285094 (PDGFB) was associated with greater LLL compared to C/T heterozygotes and T/T homozygotes.

Conclusions

The polymorphisms rs1800470, rs2285094 and rs6999447 of the TGFB1, PDGFB and VEGF-A genes, respectively, are associated with LLL in patients with SCAD treated by PCI with a metal stent implantation.  相似文献   
46.
European wolf (Canis lupus) populations have suffered extensive decline and range contraction due to anthropogenic culling. In Bulgaria, although wolves are still recovering from a severe demographic bottleneck in the 1970s, hunting is allowed with few constraints. A recent increase in hunting pressure has raised concerns regarding long-term viability. We thus carried out a comprehensive conservation genetic analysis using microsatellite and mtDNA markers. Our results showed high heterozygosity levels (0.654, SE 0.031) and weak genetic bottleneck signals, suggesting good recovery since the 1970s decline. However, we found high levels of inbreeding (F IS  = 0.113, SE 0.019) and a N e/N ratio lower than expected for an undisturbed wolf population (0.11, 95 % CI 0.08–0.29). We also found evidence for hybridisation and introgression from feral dogs (C. familiaris) in 10 out of 92 wolves (9.8 %). Our results also suggest admixture between wolves and local populations of golden jackals (C. aureus), but less extensive as compared with the admixture with dogs. We detected local population structure that may be explained by fragmentation patterns during the 1970s decline and differences in local ecological characteristics, with more extensive sampling needed to assess further population substructure. We conclude that high levels of inbreeding and hybridisation with other canid species, which likely result from unregulated hunting, may compromise long-term viability of this population despite its current high genetic diversity. The existence of population subdivision warrants an assessment of whether separate management units are needed for different subpopulations. Our study highlights conservation threats for populations with growing numbers but subject to unregulated hunting.  相似文献   
47.
PurposeTo determine using swept-source optical coherence tomography (SS-OCT) whether there are differences in the location of the anterior lamina cribrosa insertion (ALI) in primary open-angle glaucoma (POAG) patients and healthy subjects.MethodsFifty three eyes from 53 patients with POAG, and 53 eyes from 53 age-matched healthy subjects were included prospectively in Seoul National University Bundang Hospital. Twelve radial line B-scans centered on the optic disc in every half-clock-hour meridian were acquired using SS-OCT. The ALI position was assessed by measuring two parameters: (1) ALI distance (ALID)—the distance from the anterior scleral canal opening (ASCO) to the ALI; and (2) marginal anterior lamina cribrosa surface depth (mALCSD)—the perpendicular distance from the ASCO plane to the anterior lamina cribrosa surface. These parameters were compared between the two groups for each meridian.ResultsBoth ALID (256±54 vs. 209±37 µm, mean ± SD, p<0.001) and mALCSD (232±63 vs. 187±40 µm, p<0.001) were significantly greater in the POAG group than in the normal group. The largest difference was observed at the 6.5 o′clock and 11.5 o′clock meridians for both ALID and mALCSD. Multiple regression analysis revealed a negative correlation between age and both ALID and mALCSD in the control group, and a negative correlation between mean deviation of the visual field test and both ALID and mALCSD in the POAG group.ConclusionsThe ALI was displaced posteriorly in eyes with POAG compared to those of healthy controls. This finding suggests that the posteriorly located lamina cribrosa insertion is an important component of glaucomatous optic nerve excavation.  相似文献   
48.
Increased male prevalence has been repeatedly reported in several neurodevelopmental disorders (NDs), leading to the concept of a “female protective model.” We investigated the molecular basis of this sex-based difference in liability and demonstrated an excess of deleterious autosomal copy-number variants (CNVs) in females compared to males (odds ratio [OR] = 1.46, p = 8 × 10−10) in a cohort of 15,585 probands ascertained for NDs. In an independent autism spectrum disorder (ASD) cohort of 762 families, we found a 3-fold increase in deleterious autosomal CNVs (p = 7 × 10−4) and an excess of private deleterious single-nucleotide variants (SNVs) in female compared to male probands (OR = 1.34, p = 0.03). We also showed that the deleteriousness of autosomal SNVs was significantly higher in female probands (p = 0.0006). A similar bias was observed in parents of probands ascertained for NDs. Deleterious CNVs (>400 kb) were maternally inherited more often (up to 64%, p = 10−15) than small CNVs < 400 kb (OR = 1.45, p = 0.0003). In the ASD cohort, increased maternal transmission was also observed for deleterious CNVs and SNVs. Although ASD females showed higher mutational burden and lower cognition, the excess mutational burden remained, even after adjustment for those cognitive differences. These results strongly suggest that females have an increased etiological burden unlinked to rare deleterious variants on the X chromosome. Carefully phenotyped and genotyped cohorts will be required for identifying the symptoms, which show gender-specific liability to mutational burden.  相似文献   
49.
Three new fossils of saprotrophic fungi are presented and described from Baltic amber, dated to Eocene epoch (Paleogene, upper to mid-Eocene). All belong to Ascomycota and are represented by hyphae as well as asexual reproduction structures allowing to assign them to present genera, respectively Periconia, Penicillium and Scopulariopsis. These material provide both the first and the oldest known fossil record of the mentioned taxa, making these data valuable for the knowledge about the evolutionary history of the Ascomycota.  相似文献   
50.
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