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31.
In this article, we describe a novel autosomal recessive ichthyosis with hypotrichosis syndrome, characterized by congenital ichthyosis associated with abnormal hair. Using homozygosity mapping, we mapped the disease locus to 11q24.3-q25. We screened the ST14 gene, which encodes matriptase, since transplantation of skin from matriptase(-/-)-knockout mice onto adult athymic nude mice has been shown elsewhere to result in an ichthyosislike phenotype associated with almost complete absence of erupted pelage hairs. Mutation analysis revealed a missense mutation, G827R, in the highly conserved peptidase S1-S6 domain. Marked skin hyperkeratosis due to impaired degradation of the stratum corneum corneodesmosomes was observed in the affected individuals, which suggests that matriptase plays a significant role in epidermal desquamation.  相似文献   
32.
Gliomas are characterized by increased infiltration into the surrounding normal brain tissue. We recently reported that RTVP-1 is highly expressed in gliomas and plays a role in the migration of these cells, however the regulation of RTVP-1 expression in these cells is not yet described. In this study we examined the role of PKC in the regulation of RTVP-1 expression and found that PMA and overexpression of PKCα and PKCε increased the expression of RTVP-1, whereas PKCδ exerted an opposite effect. Using the MatInspector software, we identified a SRF binding site on the RTVP-1 promoter. Chromatin immunoprecipitation (ChIP) assay revealed that SRF binds to the RTVP-1 promoter in U87 cells, and that this binding was significantly increased in response to serum addition. Moreover, silencing of SRF blocked the induction of RTVP-1 expression in response to serum. We found that overexpression of PKCα and PKCε increased the activity of the RTVP-1 promoter and the binding of SRF to the promoter. In contrast, overexpression of PKCδ blocked the increase in RTVP-1 expression in response to serum and the inhibitory effect of PKCδ was abrogated in cells expressing a SRFT160A mutant. SRF regulated the migration of glioma cells and its effect was partially mediated by RTVP-1. We conclude that RTVP-1 is a PKC-regulated gene and that this regulation is at least partly mediated by SRF. Moreover, RTVP-1 plays a role in the effect of SRF on glioma cell migration.  相似文献   
33.
AIM:To study the immunophenotype of hematopoietic progenitor cells from cord blood (CB) grafts (n = 39) in comparison with adult apheresis grafts (AG, n = 229) and pre-apheresis peripheral blood (PAPB) samples (n = 908) using flow cytometry analysis.METHODS: First, we performed a qualitative analysis of CD34+ cell sub-populations in both CB and PAPB grafts using the standardized ISHAGE protocol and a wide panel of 20 monoclonal antibodies. Next, we stud-ied some parameters, such as the age of mothers and the weight of newborns, which can influence the qual-ity and the quantity of CD34+ cells from CB. RESULTS: We found that the percentage of apoptotic cells was high in CB in comparison to PAPB (PAPB: 4.6% ± 2.6% vs CB: 53.4% ± 5.2%, P < 0.001). In CB, the weight of newborn and the age of the mother have the influence on CD34+ cells. The follow-up of Ag CD133in the ISHAGE double platform protocol in association with CD45, CD34 and the 7’AAD shows an equal rate between the two cell populations CD133+CD45+CD34+ high and CD34+CD45+ high with a higher percentage. So, is the inclusion of Ac CD133 necessary in the pres-ent panel included in the ISHAGE methodflLast part, we showed a signif icant presence of interferon γ in CB in comparison to PAPB, the annexin showing the high number of apoptotic cells in CB. CONCLUSION: This study demonstrates that many different obstetric factors must be taken into account when processing and cryo-banking umbilical CB units for transplantation.  相似文献   
34.
Constrictive remodeling after arterial injury is related to collagen accumulation. Cross-linking has been shown to induce a scar process in cutaneous wound healing and is increased after arterial injury. We therefore evaluated the effect of cross-linking inhibition on qualitative and quantitative changes in collagen, elastin, and arterial remodeling after balloon injury in the atherosclerotic rabbit model. Atherosclerotic-like lesions were induced in femoral arteries of 28 New Zealand White rabbits by a combination of air desiccation and a high-cholesterol diet. After 1 mo, balloon angioplasty was performed in both femoral arteries. Fourteen rabbits were fed beta-aminopropionitrile (beta-APN, 100 mg/kg) and compared with 14 untreated animals. The remodeling index, i.e., the ratio of external elastic lamina at the lesion site to external elastic lamina at the reference site, was determined 4 wk after angioplasty for both groups. Pyridinoline was significantly decreased in arteries from beta-APN-treated animals compared with controls, confirming inhibition of collagen cross-linking: 0.30 (SD 0.03) and 0.52 (SD 0.02) mmol/mol hydroxyproline, respectively (P = 0.002). Scanning and transmission electron microscopy showed a profound disorganization of collagen fibers in arteries from beta-APN-treated animals. The remodeling index was significantly higher in beta-APN-treated than in control animals [1.1 (SD 0.3) vs. 0.8 (SD 0.3), P = 0.03], indicating favorable remodeling. Restenosis decreased by 33% in beta-APN-treated animals: 32% (SD 16) vs. 48% (SD 24) (P = 0.02). Neointimal collagen density was significantly lower in beta-APN-treated animals than in controls: 23.0% (SD 3.8) vs. 29.4% (SD 4.0) (P = 0.004). These findings suggest that collagen and elastin cross-linking plays a role in the healing process via constrictive remodeling and restenosis after balloon injury in the atherosclerotic rabbit model.  相似文献   
35.
Phytochemical and biological investigation of the roots of the wild Daucus carota ssp. carota afforded three new and four known compounds, including four sesquiterpenes daucane esters (1-3 [new], and 4), one polyacetylene (5), one sesquiterpene coumarin (6), and sitosterol glucoside. The structures of the new compounds were determined by comprehensive NMR studies, including DEPT, COSY, NOESY, HMQC and HMBC analyses. Based on an agar diffusion assay, 1, 2 and 4-6 were screened and found to contain a range of low antibacterial activities against four gram positive (Staphylococcus aureus, Streptomyces scabies, Bacillus subtilus, Bacillus cereus) and two gram negative species (Pseudomonas aeruginosa, Escherichia coli) as well as antifungal against Fusarium oxysporum and Aspergillus niger using cup agar diffusion assay.  相似文献   
36.
Sfar S  Hassen E  Saad H  Mosbah F  Chouchane L 《Cytokine》2006,35(1-2):21-28
OBJECTIVES: Vascular endothelial growth factor (VEGF) is a potent stimulus of angiogenesis that has an important role in many human malignancies including prostate carcinoma (PCa). We evaluated the role of the functional VEGF polymorphisms as genetic markers for PCa susceptibility and prognosis. METHODS: The study included 101 patients with PCa and [corrected] 100 age-matched healthy men. The VEGF genotypes -1154G>A were identified by allele-specific polymerase chain reaction (AS-PCR) and the genotypes -634G>C and 936C>T were identified by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR). RESULTS: A negative association was found between VEGF -1154AA genotype and PCa risk (OR=0.27; P=0.009). Furthermore, the presence of the VEGF -1154A allele appeared to be associated with a decreased [corrected] risk of higher tumor grade (OR=0.37; P=0.01). A significant increased risk of prostate cancer was associated with the VEGF -634 (GC+CC) combined genotype (OR=1.95; P=0.02). The VEGF -634C allele was associated with the aggressive phenotype of prostate cancer as defined by the high histological grade (OR=3.48; P=0.007). The VEGF -1154A/-634G haplotype was negatively associated with PCa risk (OR=0.48; P=0.005) and high tumor grade compared to low grade (OR=0.37; P=0.02). CONCLUSIONS: Genetic variations in the VEGF may predict not only PCa risk but also tumor aggressiveness.  相似文献   
37.
38.
Wang W  Attia AS  Liu L  Rosche T  Wagner NJ  Hansen EJ 《Plasmid》2006,55(1):50-57
Efforts to perform genetic analysis in Moraxella catarrhalis have been hampered by the lack of a cloning vector. M. catarrhalis strain E22 was previously shown to contain plasmid pLQ510 which lacked a selectable antibiotic resistance marker. Several methods were used to eliminate unnecessary DNA from pLQ510. Then, a 1.2 kb spectinomycin resistance cartridge, a multiple cloning site, and the origin of replication from pACYC184 were cloned into this plasmid backbone to obtain the 7.2 kb plasmid pWW102B. This new plasmid could replicate in M. catarrhalis as well as in both Escherichia coli and Haemophilus influenzae. This shuttle vector was used to clone and express two different M. catarrhalis genes, respectively, encoding an adhesin and a protein involved in serum resistance. When these two plasmids were introduced into appropriate M. catarrhalis mutants, they complemented the phenotypic deficiency of each mutant. This is the first report of functional complementation in trans in this pathogen.  相似文献   
39.
Enteric viruses are shed in the feces and may be present in environmental waters. Their detection in wastewater, even at low concentration, is a major challenge. In this study, recoveries of Echovirus 7 (EV7), virions and RNA in wastewater, using virus concentration methods were determined to evaluate the detection of infectious viruses and the possibility of recovering viral genomes. Two virus concentration methods, PEG precipitation method and two-phase separation method, were applied to recovery experiments of EV7-virions from wastewater, in parallel with recovery experiments of EV7 RNA. The titration of EV7 virions was carried out by cell culture using human rhabdomyosarcoma tumor tissue and the EV7 RNA quantification was performed by real-time PCR. The mean recovery yields of EV7 virions using the PEG precipitation method and the two-phase separation method were 78.5?±?10.99 and 83.1?±?0.28?%, respectively. Besides, EV7 RNA recoveries obtained using the PEG precipitation method were four times higher than those using the two-phase separation method. According to our results, the two methods enable to concentrate both infectious viruses and viral genomes. Moreover, considering the protocol time and cost together with the ratio of the EV7 virion recovery to the EV7 RNA recovery, the two-phase separation method (83.1/2.71?%, or 30.6) seems to be more appropriate for selective concentration of viral virions than the PEG precipitation method (78.5/10.33?%, or 7.6).  相似文献   
40.
Sounds produced by male cichlids Metriaclima zebra during aggressive interactions were recorded to conduct a detailed analysis and to search for potential individual acoustic signatures. Fish from two different size groups (small and large individuals) were analysed. The two groups were significantly different for all acoustic variables considered; six of seven features demonstrated a significant interindividual variability and most of them were correlated with the size of the emitter. A cross-validated and permuted discriminant function analysis (pDFA) separated the two groups and correctly classified around 50% of the sounds to the correct individuals. Acoustic features that best distinguished among males were the instantaneous frequency of sounds and the modulation of pulse amplitude. These results suggest that acoustic signals could bear information about individual identity. The long-term stability of this signature is likely to be weak since the signature of a growing individual may change over time.  相似文献   
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