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In the present study, we aimed to develop a polyacrylamide gel that could be used instead of bovine cervical mucus in the cervical mucus penetration test (CMPT) to obtain coherent and replicable results in bulls. The frozen semen samples of six Holstein bulls, which were divided into two fertility groups as low and high according to their non-return rate (NRR), were used. In this study, the modified CMPT (mCMPT) was carried out within 0.25 mL transparent plastic straws with an inner diameter 1.7 mm. The penetration ability of spermatozoa to bovine cervical mucus and to polyacrylamide gels swollen with two different solutions [NaCl (G1) and PBS (G2)] was compared. For the penetration test, the straws filled with cervical mucus and both gels were dipped into thawed semen samples and incubated at 37 degrees C for 15 min. After the incubation, straws were frozen in liquid nitrogen vapour and stored at -20 degrees C. On the evaluation day, the frozen straws were cut at 1.5-1.75 cm (penetration distance range=PDR1), 3.25-3.5 cm (PDR2) and 5.0-5.25 cm (PDR3), beginning from open-end of the straws. The separated frozen parts were then immediately transferred onto special counting slides by pushing with a mandrel and left to thaw. Thawed samples were covered with cover glass and penetrated spermatozoa in these parts were counted. The relation between the results and fertility of bulls was determined. In the tests performed using mucus, the number of spermatozoa determined in the high fertility group was found to be higher at PDR3 (p<0.0001) compared to the low fertility group, while in G1 spermatozoa number was significantly higher at PDR1 and PDR3 (p<0.0001). However, in G2 medium, no significant difference was observed between either of the fertility groups with respect to spermatozoa number determined at all distance ranges. In the study, we have determined that the gel swollen with NaCl produces better results and this gel can be used instead of bovine cervical mucus for the CMPT. Therefore, we have concluded that the penetration test performed by polyacrylamide gel swollen with NaCl can be a suitable technique for estimation of the potential fertility of bull spermatozoa. 相似文献
75.
Shi X Ma YQ Tu Y Chen K Wu S Fukuda K Qin J Plow EF Wu C 《The Journal of biological chemistry》2007,282(28):20455-20466
Integrin-mediated cell-matrix adhesion plays an important role in control of cell behavior. We report here that MIG-2, a widely expressed focal adhesion protein, interacts with beta1 and beta3 integrin cytoplasmic domains. Integrin binding is mediated by a single site within the MIG-2 FERM domain. Functionally, the MIG-2/integrin interaction recruits MIG-2 to focal adhesions. Furthermore, using alphaIIbbeta3 integrin-expressing Chinese hamster ovary cells, a well described model system for integrin activation, we show that MIG-2 promotes integrin activation and enhances cell-extracellular matrix adhesion. Although MIG-2 is expressed in many cell types, it is deficient in certain colon cancer cells. Expression of MIG-2, but not of an integrin binding-defective MIG-2 mutant, in MIG-2-null colon cancer cells strengthened cell-matrix adhesion, promoted focal adhesion formation, and reduced cell motility. These results suggest that the MIG-2/integrin interaction is an important element in the cellular control of integrin-mediated cell-matrix adhesion and that loss of this interaction likely contributes to high motility of colon cancer cells. 相似文献
76.
Ju DH Choi MK Ahn JH Kim MH Cho JC Kim T Kim T Seong CN Ka JO 《Journal of microbiology and biotechnology》2007,17(2):253-261
Molecular and cultivation techniques were used to characterize the bacterial communities of biobead reactor biofilms in a sewage treatment plant to which an Aerated Up-Flow Biobead process was applied. With this biobead process, the monthly average values of various chemical parameters in the effluent were generally kept under the regulation limits of the effluent quality of the sewage treatment plant during the operation period. Most probable number (MPN) analysis revealed that the population of denitrifying bacteria was abundant in the biobead #1 reactor, denitrifying and nitrifying bacteria coexisted in the biobead #2 reactor, and nitrifying bacteria prevailed over denitrifying bacteria in the biobead #3 reactor. The results of the MPN test suggested that the biobead #2 reactor was a transition zone leading to acclimated nitrifying biofilms in the biobead #3 reactor. Phylogenetic analysis of 16S rDNA sequences cloned from biofilms showed that the biobead #1 reactor, which received a high organic loading rate, had much diverse microorganisms, whereas the biobead #2 and #3 reactors were dominated by the members of Proteobacteria. DGGE analysis with the ammonia monooxygenase (amoA) gene supported the observation from the MPN test that the biofilms of September were fully developed and specialized for nitrification in the biobead reactor #3. All of the DNA sequences of the amoA DGGE bands were very similar to the sequence of the amoA gene of Nitrosomonas species, the presence of which is typical in the biological aerated filters. The results of this study showed that organic and inorganic nutrients were efficiently removed by both denitrifying microbial populations in the anaerobic tank and heterotrophic and nitrifying bacterial biofilms well-formed in the three functional biobead reactors in the Aerated Up-Flow Biobead process. 相似文献
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Susceptibility to tuberculosis (TB) may be affected by host genetic factors. Elevated levels of transforming growth factor-beta 1 (TGF-β1) were found in plasma of patients with active TB compared with those of healthy contacts. To investigate the association of TGF-β1 gene polymorphisms (C-509T and T869C) and plasma levels with the risk of TB in Hong Kong Chinese adults, a case-control study was carried out on 174 active TB patients and 174 healthy controls matched for age, gender and smoking. Blood samples from 180 blood donors served as another control group. Genotyping was carried out on genomic DNA using polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Plasma TGF-β1 was measured by commercially available ELISA kit. We found no differences in the distribution of genotypes or alleles of TGF-β1 gene polymorphisms at C-509T and T869C between patients and either group of healthy controls. Patients with TB had elevated plasma TGF-β1 levels compared with healthy controls irrespective of their genotypes (p < 0.001). In conclusion, TGF-β1 gene polymorphism at C-509T and T869C is not associated with TB susceptibility in Hong Kong Chinese adults, but elevated plasma TGF-β1 levels suggests that this cytokine may play a role in the pathogenesis of tuberculosis. 相似文献
79.
Infectious antigens may be triggers for the exacerbation of systemic lupus erythematosus. The underlying mechanism causing
acceleration and exacerbation of lupus nephritis (LN) is largely unknown. Bacterial lipopolysaccharide (LPS) is capable of
inducing an accelerated model of LN in NZB/W mice, featuring diffuse proliferation of glomerular resident cells. We hypothesized
that mesangial cells (MCs) from LN subjects are more responsive to LPS than normal subjects. Cultured primary NZB/W and DBA/W
(nonautoimmune disease-prone strain with MHC class II molecules identical to those of NZB/W) MCs were used. Monocyte chemoattractant
protein-1 (MCP-1) and osteopontin (OPN) expressions either in the baseline (normal culture) condition or in the presence of
LPS were evaluated by real-time PCR, ELISA, or western blot analysis. NF-κB was detected by ELISA, electrophoresis mobility-shift
assay, and immunofluorescence. First, either in the baseline condition or in the presence of LPS, NZB/W MCs produced significantly
higher levels of MCP-1 and OPN than the DBA/W MC controls. Second, NZB/W MCs expressed significantly higher levels of Toll-like
receptor 4, myeloid differentiation factor 88, and NF-κB than the DBA/W MC controls, both receiving exactly the same LPS treatment.
In conclusion, NZB/W MCs are significantly more sensitive than their normal control DBA/W MCs in producing both MCP-1 and
OPN. With LPS treatment, the significantly elevated levels of both chemokines produced by NZB/W MCs are more likely due to
a significantly greater activation of the Toll-like receptor 4-myeloid differentiation factor 88-associated NF-κB pathway.
The observed abnormal molecular events provide an intrarenal pathogenic pathway involved in an accelerated type of LN, which
is potentially infection triggered. 相似文献
80.
We report a 21-year-old patient with a de novo mosaic, analphoid ring of chromosome 15q22.2-->q24.1. The clinical features of this patient are mild and include tall stature, obesity, striae distensae in the hypogastrium, malocclusion and bilateral gynecomastia with scarce glandular tissue. M-FISH and FISH using a chromosome 15 painting probe indicated that the ring is of chromosome 15 origin. Further CGH analysis and FISH with the PML locus-specific probe demonstrated that the extra material derived from the medial part of the long arm of chromosome 15, including two bands, q22 and q23. Additionally, FISH with BAC probes specific for 15q allowed for a localization of the breakpoints at 15q22.2 and 15q24.1, distal to clones RP11-30M4 and RP11-500O23 respectively. We discuss the relationship between the patient's genotype and phenotype comparing it to reported cases of trisomy of medial 15q. 相似文献