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41.
Changes in immunological system are one of dysfunctions reported in schizophrenia. Some changes based on an imbalance between Th1 and Th2 cytokines results from cytokine gene polymorphisms. Interleukin-4 gene (IL4) is considered as a potential candidate gene in schizophrenia association studies. The aim of the current case-control study was to examine whether the -590C/T (rs2243250) and -33C/T (rs2070874) IL4 gene polymorphisms are implicated in paranoid schizophrenia development in the Polish population. Genotyping of polymorphisms was performed by using PCR-RFLP technique. The genotypes and alleles distribution of both SNPs were analysed in patients (n = 182) and healthy individuals constituted the control group (n = 215). The connection between some clinical variables and studied polymorphisms has been examined as well. We did not revealed any association between the -590C/T and -33C/T polymorphisms and paranoid schizophrenia. In case of both SNPs the homozygous TT genotype was extremely rare. Both polymorphic sites of the IL4 gene were found to be in a very strong linkage disequilibrium. However we did not identify a haplotype predispose to paranoid schizophrenia. No associations were also observed between the clinical course and psychopathology of the disease and the genotypes of both analysed polymorphisms. Our results suggest that the polymorphisms -590C/T in IL4 gene promoter region and -33C/T in the 5'-UTR are not involved in the pathophysiology of paranoid schizophrenia in Polish residents.  相似文献   
42.
Experiments on semen collection and preservation were undertaken by Wroc?aw University of Environmental and Life Sciences and Forestry Wis?a, Poland to assist in the protection of the capercaillie (Tetrao urogallus L.) and to create an ex situ in vitro cryobank. Semen was collected from 11 captive-bred males, using dorsoabdominal massage. Ejaculates once obtained were diluted 3-fold at room temperature with EK diluent and then a number of them were stored at 4 °C for 18, 24, and 48 hours, while the remaining ejaculates were equilibrated with 6% dimethylacetamide and frozen by pipetting, drop-by-drop directly onto a liquid nitrogen surface. Frozen pellets were thawed at 60 °C in a water bath after 4 to 28 mo of storage. In total, 103 individually collected ejaculates (54 stored as liquid and 49 frozen in liquid nitrogen) were of appropriate value for further processing. The volume of ejaculates varied from 30 to 240 μL; spermatozoa concentration from 70 × 106 mL−1 to 1950 × 106 mL−1. The total amount of live spermatozoa in the fresh semen varied from 85.3% to 99.0%, of which from 41.1% to 85.3% were morphologically normal. Among morphologically abnormal forms, bulb-head (5.6% to 36.0%) and midpiece deformations (1.3% to 16.6%) were the most frequent. Dilution and semen storage up to 24 h at 4 °C did not affect the semen quality, as far as motility and sperm morphology are concerned. A significant (P < 0.05) decrease in total live (94.9 vs. 91.7%) and live normal cells (66.4 vs. 56.7%) was observed after 48 h. About 30% to 40% of spermatozoa remained motile. Cryopreservation significantly decreased (P < 0.05) the total number of live and live normal spermatozoa however, in relation to the fresh semen, their average content was 44.1% and 37.4%, respectively. Significant (P < 0.05) individual differences were observed in the quality of the fresh, liquid stored and the frozen-thawed semen assessed in terms of spermatozoa motility and morphology. After a single insemination with thawed semen containing 9.7 million live normal cells, 80% fertility and 100% hatchability were achieved. The obtained results indicate for the first time that there is the potential to use liquid stored and cryopreserved capercaillie semen to support conservation measures for the maintenance of genetic diversity, as well as to increase the number of reintroduced progeny of this endangered grouse species.  相似文献   
43.
The objective of the present experiments was to produce the intergeneric hybrids of domesticated and wild goose via artificial insemination with fresh and frozen-thawed semen. The experiments were carried out during two successive goose reproductive seasons, on eight five-year-old Canada Goose (Branta canadensis L.) males used as semen donors and 16 two-year-old White Ko?uda geese designated to fertility tests. Pooled semen was collected twice a week by the dorso-abdominal massage. In freshly collected semen, ejaculate volume, color, consistency, degree of fecal or blood contamination, spermatozoa concentration, motility, and morphology were evaluated. Part of the semen collected in the first year of the experiment (Experiment 1) was used for geese insemination with fresh semen, while the remainder was frozen. In Experiment 2 all samples were subjected exclusively to freezing procedure. Geese were inseminated once a week with fresh semen in a dose of 80 μl or 160 μl, and twice a week with frozen-thawed semen in a dose of 80 μl (160 μl per wk) or 100 μl (200 μl per wk). Eggs were set weekly and incubated up to hatching.The volume of ejaculates varied from 0.100 to 0.470 ml; spermatozoa concentration from 140 to 310 million ml−1; progressive movement was observed in 40 to 60% of spermatozoa; the percentage of total live spermatozoa ranged from 69.3 to 92.0%, the highest percentage (34.0-68.3) was represented by live normal spermatozoa and those with bulb-head (13.3-41.0). Cryopreservation caused a decrease in percentage of motile cells to 30%; total live spermatozoa contribution by 27.2%p, including those live normal by 15.9%p (in relation to the fresh semen), bulb-head spermatozoa by 10.9%p, and increase (by 5.9%p) in number of spermatozoa with other deformations. Goose insemination 1×/week with fresh semen containing about 10.3 million live normal spermatozoa resulted in 66.7% of fertile eggs and with dose higher by 2.8 million spermatozoa (on average) the fertility increased by 20.9%p (up to 87.6% on average). Hatchability from set and fertile eggs was 55.9% and 83.9% vs. 66.3% and 75.6%, respectively. After twice a week insemination with frozen-thawed semen containing about 10.2 million live normal cells 58.2% eggs were fertile; hatchability from set eggs was 42.8% and from fertile eggs 71.7%, while insemination dose increase by 2.7 million spermatozoa per week caused a fertilization increase by 3.8%p (62.0% on average), this increase was not statistically significant, but hatchability from the fertile eggs (95.4%), was significantly (P < 0.05) higher.The use of AI with fresh semen in the creation of intergeneric hybrids of Canada goose males and White Ko?uda females allows a high level of egg fertility to be obtained. Furthermore, one limitation which is the short reproductive season of the Canada goose may be overcome by the use of cryopreserved semen.  相似文献   
44.
Oscypek is a traditional Polish scalded-smoked cheese, with a protected-designation-of-origin (PDO) status, manufactured from raw sheep's milk without starter cultures in the Tatra Mountains region of Poland. This study was undertaken in order to gain insight into the microbiota that develops and evolves during the manufacture and ripening stages of Oscypek. To this end, we made use of both culturing and the culture-independent methods of PCR followed by denaturing gradient gel electrophoresis (PCR-DGGE) and pyrosequencing of 16S rRNA gene amplicons. The culture-dependent technique and PCR-DGGE fingerprinting detected the predominant microorganisms in traditional Oscypek, whereas the next-generation sequencing technique (454 pyrosequencing) revealed greater bacterial diversity. Besides members of the most abundant bacterial genera in dairy products, e.g., Lactococcus, Lactobacillus, Leuconostoc, Streptococcus, and Enterococcus, identified by all three methods, other, subdominant bacteria belonging to the families Bifidobacteriaceae and Moraxellaceae (mostly Enhydrobacter), as well as various minor bacteria, were identified by pyrosequencing. The presence of bifidobacterial sequences in a cheese system is reported for the first time. In addition to bacteria, a great diversity of yeast species was demonstrated in Oscypek by the PCR-DGGE method. Culturing methods enabled the determination of a number of viable microorganisms from different microbial groups and their isolation for potential future applications in specific cheese starter cultures.  相似文献   
45.
One of the major lipid peroxidation products trans-4-hydroxy-2-nonenal (HNE), forms cyclic propano- or ethenoadducts bearing six- or seven-carbon atom side chains to G > C ? A > T. To specify the role of SOS DNA polymerases in HNE-induced mutations, we tested survival and mutation spectra in the lacZα gene of M13mp18 phage, whose DNA was treated in vitro with HNE, and which was grown in uvrA? Escherichia coli strains, carrying one, two or all three SOS DNA polymerases. When Pol IV was the only DNA SOS polymerase in the bacterial host, survival of HNE-treated M13 DNA was similar to, but mutation frequency was lower than in the strain containing all SOS DNA polymerases. When only Pol II or Pol V were present in host bacteria, phage survival decreased dramatically. Simultaneously, mutation frequency was substantially increased, but exclusively in the strain carrying only Pol V, suggesting that induction of mutations by HNE is mainly dependent on Pol V. To determine the role of Pol II and Pol IV in HNE induced mutagenesis, Pol II or Pol IV were expressed together with Pol V. This resulted in decrease of mutation frequency, suggesting that both enzymes can compete with Pol V, and bypass HNE-DNA adducts in an error-free manner. However, HNE-DNA adducts were easily bypassed by Pol IV and only infrequently by Pol II.Mutation spectrum established for strains expressing only Pol V, showed that in uvrA? bacteria the frequency of base substitutions and recombination increased in relation to NER proficient strains, particularly mutations at adenine sites. Among base substitutions A:T  C:G, A:T  G:C, G:C  A:T and G:C  T:A prevailed.The results suggest that Pol V can infrequently bypass HNE-DNA adducts inducing mutations at G, C and A sites, while bypass by Pol IV and Pol II is error-free, but for Pol II infrequent.  相似文献   
46.
ABSTRACT: BACKGROUND: Diabetes (DM) deteriorates the prognosis in patients with coronary heart disease. However, the prognostic value of different glucose abnormalities (GA) other than DM in subjects with acute myocardial infarction (AMI) treated invasively remains unclear. AIMS: To assess the incidence and impact of GA on clinical outcomes in AMI patients treated with percutaneous coronary intervention (PCI). METHODS: A single-center, prospective registry encompassed 2733 consecutive AMI subjects treated with PCI. In all in-hospital survivors (n = 2527, 92.5 %) without the history of DM diagnosed before or during index hospitalization standard oral glucose tolerance test (OGTT) was performed during stable condition before hospital discharge and interpreted according to WHO criteria. The mean follow-up period was 37.5 months. RESULTS: The incidence of GA was as follows: impaired fasting glycaemia - IFG (n = 376, 15 %); impaired glucose tolerance - IGT (n = 560, 22 %); DM (n = 425, 17 %); new onset DM (n = 384, 15 %); and normal glucose tolerance NGT (n = 782, 31 %). During the long-term follow-up, death rate events for previously known DM, new onset DM and IGT were significantly more frequent than those for IFG and NGT (12.3; 9.6 and 9.4 vs. 5.6 and 6.4 %, respectively, P < 0.05). The strongest and common independent predictors of death in GA patients were glomerular filtration rate < 60 ml/min/1,73 m^2 (HR 2.0 and 2.8) and left ventricle ejection fraction < 35 % (HR 2.5 and 1.8, all P < 0.05) respectively. CONCLUSIONS: Glucose abnormalities are very common in AMI patients. DM, new onset DM and IGT increase remote mortality. Impaired glucose tolerance bears similar long-term prognosis as diabetes.  相似文献   
47.
Pemphigus vulgaris (PV) is an autoimmune epidermal blistering disease caused by autoantibodies directed against the desmosomal cadherin desmoglein-3 (Dsg3). Significant advances in our understanding of pemphigus pathomechanisms have been derived from the generation of pathogenic monoclonal Dsg3 antibodies. However, conflicting models for pemphigus pathogenicity have arisen from studies using either polyclonal PV patient IgG or monoclonal Dsg3 antibodies. In the present study, the pathogenic mechanisms of polyclonal PV IgG and monoclonal Dsg3 antibodies were directly compared. Polyclonal PV IgG cause extensive clustering and endocytosis of keratinocyte cell surface Dsg3, whereas pathogenic mouse monoclonal antibodies compromise cell-cell adhesion strength without causing these alterations in Dsg3 trafficking. Furthermore, tyrosine kinase or p38 MAPK inhibition prevents loss of keratinocyte adhesion in response to polyclonal PV IgG. In contrast, disruption of adhesion by pathogenic monoclonal antibodies is not prevented by these inhibitors either in vitro or in human skin explants. Our results reveal that the pathogenic activity of polyclonal PV IgG can be attributed to p38 MAPK-dependent clustering and endocytosis of Dsg3, whereas pathogenic monoclonal Dsg3 antibodies can function independently of this pathway. These findings have important implications for understanding pemphigus pathophysiology, and for the design of pemphigus model systems and therapeutic interventions.  相似文献   
48.
The objective of this study was to investigate the protein and mRNA expression of vascular endothelial growth factor (VEGF), VEGFR-1 (fms-like tyrosine kinase, Flt-1) and VEGFR-2 (fetal liver kinase-1/kinase insert domain-containing receptor, Flk-1/KDR) in the endometrium during the estrous cycle and early pregnancy in pigs. The VEGF-receptor system was localized in epithelial and stromal cells, blood vessels, and myometrium. Western blot analysis showed higher levels of VEGF protein during the periovulatory and periimplantation periods (P < 0.001, and P < 0.05, respectively). Constant expression of VEGF mRNA during the cycle and significant upregulation on Days 22-25 of gestation (vs. Days 9-17; P < 0.001) was observed. Stable levels of VEGFR-1 mRNA and protein were detected in the endometrium of cyclic animals. However, higher VEGFR-1 protein expression was found on Days 16-17 of the estrous cycle (P < 0.01) and Days 13-15 of gestation (P < 0.05). Protein expression of VEGFR-2 was elevated on Days 2-4 of the estrous cycle (P < 0.001), but mRNA levels were constant during the cycle. In pregnancy, VEGFR-2 protein expression started to increase after Day 15 (vs. Days 9-12; P < 0.05), but induction of VEGFR-2 mRNA expression occurred earlier on Days 13-15. It appears from the present study that the VEGF-receptor system is regulated in a temporal and spatial manner during the estrous cycle and early pregnancy in pigs. The results suggest that VEGF-A family members are probably involved in appropriate preparation of endometrium for implantation and in vascular events during implantation in pigs.  相似文献   
49.
Lysophosphatidic acid (LPA) stimulates cells by activation of five G-protein-coupled receptors, termed LPA 1-5. The LPA 1 receptor is the most widely expressed and is a major regulator of cell migration. In this study, we show that phorbol ester (PMA)-induced internalization of the LPA(1) receptor requires clathrin AP-2 complexes, protein kinase C, and a distal dileucine motif (amino acids 352 and 353) in the cytoplasmic tail but not beta-arrestin. Agonist-dependent internalization of LPA 1, however, requires a cluster of serine residues (amino acids 341-347) located proximal to the dileucine motif, beta-arrestin, and to a lesser extent clathrin AP-2. The serine cluster of LPA 1 is required for beta-arrestin2-GFP translocation to the plasma membrane and signal desensitization. In contrast, the dileucine motif (IL) is required for both basal and PMA-induced internalization. Evidence for the beta-arrestin independence of PMA-induced internalization of LPA 1 comes from the observations that beta-arrestin2-GFP is not recruited to the plasma membrane upon PMA treatment and that LPA 1 is readily internalized in beta-arrestin1/2 knock-out mouse embryonic fibroblasts. These results indicate that distinct molecular mechanisms regulate agonist-dependent and PMA-dependent internalization of the LPA 1 receptor.  相似文献   
50.
Pemphigus vulgaris (PV) is a life-threatening autoimmune disease characterized by oral mucosal erosions and epidermal blistering. The autoantibodies generated target the desmosomal cadherin desmoglein-3 (Dsg3). Previous studies demonstrate that upon PV IgG binding, Dsg3 is internalized and enters an endo-lysosomal pathway where it is degraded. To define the endocytic machinery involved in PV IgG-induced Dsg3 internalization, human keratinocytes were incubated with PV IgG, and various tools were used to perturb distinct endocytic pathways. The PV IgG.Dsg3 complex failed to colocalize with clathrin, and inhibitors of clathrin- and dynamin-dependent pathways had little or no effect on Dsg3 internalization. In contrast, cholesterol binding agents such as filipin and nystatin and the tyrosine kinase inhibitor genistein dramatically inhibited Dsg3 internalization. Furthermore, the Dsg3 cytoplasmic tail specified sensitivity to these inhibitors. Moreover, inhibition of Dsg3 endocytosis with genistein prevented disruption of desmosomes and loss of adhesion in the presence of PV IgG. Altogether, these results suggest that PV IgG-induced Dsg3 internalization is mediated through a clathrin- and dynamin-independent pathway and that Dsg3 endocytosis is tightly coupled to the pathogenic activity of PV IgG.  相似文献   
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