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61.
There is a difference in the susceptibility to inflammation between the umbilical vein (UV) and the umbilical arteries (UAs). This led us to hypothesize that there is an intrinsic difference in the pro-inflammatory response between UA and UV. Real-time quantitative RT-PCR and microarray analysis revealed higher expression of interleukin (IL)-1β and IL-8 mRNA in the UV and differential expression of 567 genes between the UA and UV associated with distinct biological processes, including the immune response. Differential expression of human leukocyte antigen (HLA)-DRA mRNA between the UA and UV was due to unexpected HLA-DR+ cells migrating via the umbilical vessels into Wharton's jelly, more frequently in the UV. A significant proportion of these cells co-expressed CD45 and type I pro-collagen, and acquired CD163 or α-smooth muscle actin immunoreactivity in Wharton's jelly. Migrating cells were also found in the chorionic and stem villous vessels. Furthermore, the extent of migration increased with progression of gestation, but diminished in intrauterine growth restriction (IUGR). The observations herein strongly suggest that circulating foetal fibrocytes, routing via umbilical and placental vessels, are a reservoir for key cellular subsets in the placenta. This study reports fibrocytes in the human umbilical cord and placenta for the first time, and a novel role for both circulating foetal cells and the umbilical vessels in placental development, which is deranged in IUGR.  相似文献   
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63.
The role of pelvic floor muscle contraction in the genesis of anal canal pressure is not clear. Recent studies have suggested that vaginal distension increases pelvic floor muscle contraction. We studied the effects of vaginal distension on anal canal pressure in 15 nullipara asymptomatic women. Anal pressure, rest, and squeeze were measured using station pull-through manometry techniques with no vaginal probe, a 10-mm vaginal probe, and a 25-mm vaginal probe in place. Rest and squeeze vaginal pressures were significantly higher when measured with the 25-mm probe compared with the 10-mm probe, suggesting that vaginal distension enhances pelvic floor contraction. In the presence of the 25-mm vaginal probe, rest and squeeze anal pressures in the proximal part of the anal canal were significantly higher compared with no vaginal probe or the 10-mm vaginal probe. On the other hand, distal anal pressures were not affected by any of the vaginal probes. Ultrasound imaging of the pelvic floor revealed that vaginal distension increased the anterior-posterior length of the puborectalis muscle. Atropine at 15 micro g/kg had no influence on the rest and squeeze anal pressures with or without vaginal distension. Our data suggest that pelvic floor contractions increase pressures in the proximal part of the anal canal, which is anatomically surrounded by the puborectalis muscle. We propose that pelvic floor contraction plays an important role in the fecal continence mechanism by increasing anal canal pressure.  相似文献   
64.
The NH2-terminal Jun kinases (JNKs) function in diverse roles through phosphorylation and activation of AP-1 components including ATF2 and c-Jun. However, the genes that mediate these processes are poorly understood. A model phenotype characterized by rapid activation of Jun kinase and enhanced DNA repair following cisplatin treatment was examined using chromatin immunoprecipitation with antibodies against ATF2 and c-Jun or their phosphorylated forms and hybridization to promoter arrays. Following genotoxic stress, we identified 269 genes whose promoters are bound upon phosphorylation of ATF2 and c-Jun. Binding did not occur following treatment with transplatin or the JNK inhibitor SP600125 or JNK-specific siRNA. Of 89 known DNA repair genes represented on the array, 23 are specifically activated by cisplatin treatment within 3-6 hr. Thus, the genotoxic stress response occurs at least partly via activation of ATF2 and c-Jun, leading to large-scale coordinate gene expression dominated by genes of DNA repair.  相似文献   
65.
Spermatozoa from sterile t6/tw32 and control fertile +/+, T/tw32, T/t6 mice were compared for their abilities to hydrolyse protein matrices and for their levels of acrosin activity. The data show that the immature and mature gametes from both the experimental and control males hydrolyse protein matrices. The quantitative acrosin assays show, however, that the mature gametes from the intercomplement males have significantly less total acrosin activity than any of the control groups of gametes. These findings suggest that this reduced acrosin activity is an additional phenotypic expression of the intercomplement genotype which results in male sterility.  相似文献   
66.
Differential response of stress fibers and myofibrils to gelsolin   总被引:6,自引:0,他引:6  
The actin-severing activity of human platelet gelsolin was analyzed on embryonic skeletal and cardiac myofibrils, and on stress fibers in non-muscle cells. These subcellular structures, although in all three cell types composed of contractile proteins arranged in sarcomeric units, were found to respond differently to gelsolin. The myofibrils in permeabilized myotubes or cardiac cells, as well as in living, microinjected muscle cells proved resistant to a wide concentration range of gelsolin. The same was found for the "mini-sarcomeres" which are seen in developing muscle cells. In contrast, stress fibers in microinjected fibroblasts or epithelial cells, as well as in permeabilized cells, were broken down rapidly by the platelet gelsolin. We conclude from these results that the mini-sarcomeres in embryonic myotubes and cardiac myocytes are not identical with stress fibers.  相似文献   
67.
Migraine is a neurovascular disorder, and hence, any alteration in vascular endothelial function by either the endothelin system or the apolipoproteins may contribute to its pathophysiology. Thus, we investigated the role of EDNRA -231 G>A and APOE HhaI polymorphism for a possible association with migraine. Genotyping of 613 subjects consisting of 217 migraine subjects, 217 healthy controls (HC), and 179 subjects with tension-type headache was performed using the standard PCR-RFLP method. Data were analyzed by taking the Bonferroni-corrected p-values into account. We found significant difference in the frequency of EDNRA AA genotype between migraine subjects when compared with HC (p-value?=?0.005; OR?=?2.542; confidence interval [CI]?=?1.329-4.863). A similar trend was shown by female migraine subjects at genotype and allele levels. The association of EDNRA -231 G>A polymorphism with migraine fit a recessive model (migraine vs. HC, p-value?=?0.002; OR?=?1.917; CI?=?2.268-2.898). Female migraineurs without aura (MO) followed a similar trend. In the case of APOE HhaI polymorphism, E3E4 and E2E3 genotypes conferred risk when taken together in case of migraine versus HC (p-value?=?0.005; OR?=?2.715; CI?=?1.342-5.490) and migraine with aura (MA) versus HC (p-value?=?0.004; OR?=?3.422; CI?=?7.992). The risk was also seen after stratification on the basis of gender in female migraineurs (total migraine and MA). The interaction of EDNRA and APOE genotypes did not show further significance. The AA genotype and A allele of EDNRA -231 G>A polymorphism conferred risk for total migraine and MO. In APOE HhaI polymorphism, E3E4 and E2E3 conferred risk when taken together in total migraine and MA.  相似文献   
68.
Calmodulin (CaM) is the major component of calcium signaling pathways mediating the action of various effectors. Transient increases in the intracellular calcium level triggered by a variety of stimuli lead to the formation of Ca(2+)/CaM complexes, which interact with and activate target proteins. In the present study the role of Ca(2+)/CaM in the regulation of the ligand-dependent activation of the epidermal growth factor receptor (EGFR) has been examined in living cells. We show that addition of different cell permeable CaM antagonists to cultured cells or loading cells with a Ca(2+) chelator inhibited ligand-dependent EGFR auto(trans)phosphorylation. This occurred also in the presence of inhibitors of protein kinase C, CaM-dependent protein kinase II and calcineurin, which are known Ca(2+)- and/or Ca(2+)/CaM-dependent EGFR regulators, pointing to a direct effect of Ca(2+)/CaM on the receptor. Furthermore, we demonstrate that down-regulation of CaM in conditional CaM knock out cells stably transfected with the human EGFR decreased its ligand-dependent phosphorylation. Substitution of six basic amino acid residues within the CaM-binding domain (CaM-BD) of the EGFR by alanine resulted in a decreased phosphorylation of the receptor and of its downstream substrate phospholipase Cγ1. These results support the hypothesis that Ca(2+)/CaM regulates the EGFR activity by directly interacting with the CaM-BD of the receptor located at its cytosolic juxtamembrane region.  相似文献   
69.

Background  

Chlamydial Inclusion membrane proteins (Incs), are involved in biochemical interactions with host cells and infecting Chlamydiae. We have previously reported the role of two Chlamydia trachomatis (CT) Incs, namely IncB and IncC in generating host immunity in CT infected women. Emerging data shows involvement of Inc stimulated CD4 positive T cells in aiding host immunity in infected fertile and infertile women through the secretion of interferon gamma. However the lack of data on the intra-cytokine interplay to these Incs in infected cell milieu prompted us to investigate further.  相似文献   
70.
Selective inhibition of inducible nitric oxide synthases (iNOS) has been a challenging problem for researchers pursuing work in finding methods to treat inflammatory disorders, shock, etc. Though many inhibitors have been studied to date, all are associated with selectivity or potency problems. Additionally, most of the reported compounds have several similarities and fewer number of novel structures are being tried. There is an increasing need to design novel molecules for this target. In this work, de novo design using LUDI, combined with docking analysis using FlexX has been employed in an attempt to identify novel scaffolds. Benzene-1,2-diamines were identified which could mimic the interactions of the substrate analogs and other inhibitors. Comparative docking scores in each of the isoforms of nitric oxide synthase were employed to recognize hits for iNOS selectivity. Figure Figure shows the docked poses of the ligand M226 along with that of the reference GW274150. (FlexX analysis)  相似文献   
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