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101.
Steroidogenic factor‐1 (SF1), encoded by the NR5A1 gene, is a key regulator of steroidogenesis and reproductive development. NR5A1 mutations described in 46,XY patients with disorders of sex development (DSD) can be associated with a range of conditions of phenotypes; however, the genotype–phenotype correlation remains elusive in many cases. In the present study, we describe the impact of five NR5A1 variants (three novel: p.Arg39Cys, p.Ser32Asn, and p.Lys396Argfs*34; and two previously described: p.Cys65Tyr and p.Cys247*) on protein function, identified in seven patients with 46,XY DSD. In vitro functional analyses demonstrate that NR5A1 mutations impair protein functions and result in the DSD phenotype observed in our patients. Missense mutations in the DNA binding domain and the frameshift mutation p.Lys396Argfs*34 lead to both, markedly affected transactivation assays, and loss of DNA binding, whereas the mutation p.Cys247* retained partial transactivation capacity and the ability to bind a consensus SF1 responsive element. SF1 acts in a dose‐dependent manner and regulates a cascade of genes involved in the sex determination and steroidogenesis, but in most cases reported so far, still lead to a sufficient adrenal steroidogenesis and function, just like in our cases, in which heterozygous mutations are associated to 46,XY DSD with intact adrenal steroid biosynthesis.  相似文献   
102.
Alpha‐melanocyte stimulating hormone (α‐MSH) is a neuropeptide exhibiting anti‐inflammatory activity in experimental models of autoimmune diseases. However, no studies thus far have examined the effects of α‐MSH on systemic lupus erythematosus (SLE). This study aimed to determine the effects of an α‐MSH agonist in induced murine lupus. Here we employed female Balb/cAn mice in which lupus was induced by pristane. Groups of lupus animals were treated daily with the α‐MSH analogue [Nle4, DPhe7]‐α‐MSH (NDP–MSH) (1·25 mg/kg) injected intraperitoneally or saline for 180 days. Normal animals comprised the control group. Arthritis incidence, plasma immunoglobulin (Ig)G isotypes, anti‐nuclear antibodies (ANA) and plasma cytokines were evaluated. Renal function was assessed by proteinuria and histopathological lesion. Glomerular levels of IgG, α‐smooth muscle actin (α‐SMA), inducible nitric oxide synthase (iNOS), C3, CD3, melanocortin receptors (MCR)1, corticotrophin‐releasing factor (CRF) and α‐MSH was estimated by immunohistochemistry. When compared with normal controls, lupus animals exhibited increased arthritis, IgG levels, ANA, interleukin (IL)‐6, IL‐10, proteinuria and mesangial cell proliferation together with glomerular expression of α‐SMA and iNOS. Glomerular expression of MCR1 was reduced in lupus animals. NDP‐MSH treatment reduced arthritis scores by 70% and also diminished IgG1 and IgG2a levels and ANA incidence. In the glomerulus, NDP–MSH treatment reduced cellularity by 50% together with reducing IgG deposits, and expression levels of α‐SMA, iNOS and CRF were also all decreased. Taken together, our results suggest for the first time that α‐MSH treatment improves several parameters of SLE disease activity in mice, and indicate that this hormone is an interesting potential future treatment option.  相似文献   
103.
The cattle tick, Rhipicephalus (Boophilus) microplus, has caused serious harm to livestock raising in Brazil, considering the costs of controlling it, loss of revenue due to smaller production of milk and meat, and damage to leather, in addition to transmitting diseases. The use of medicinal plants is considered an alternative to the recurring resistance to chemicals. Due to the need for efficient alternatives with less environmental impact, this study aimed to develop contact formulations with essential oils from the Java citronella (Cymbopogon winterianus) and clove (Syzygium aromaticum) plants and to assess in vitro the effects in different stages of the tick cycle. In the present study, concentrations from 0.5–15.0 % of the essential oils incorporated in the formulations were used. The ticks from different geographical areas were treated with those formulations, and their effects on the production levels of eggs, on the larvae hatching, and their efficiency on ticks were assessed. The obtained results were compared with other commercial acaricidal products. After the 20th day of treatment, the formulations with citronella essential oil had 2.09–55.51 % efficiency, depending on the concentration of the oil incorporated. The efficiency of the treatment with formulations containing clove essential oil was higher, from 92.47–100 %. The results showed the acaricidal effects of the formulations tested when compared to commercial chemical products. In vivo studies should be performed in order to assess the efficiency of those formulations in the fields, aiming to use these products as an alternative for controlling cattle ticks.  相似文献   
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106.
This study describes intra-hospital survival rates of very-low-birth-weight infants, as well as factors present at birth associated with survival, during a period of 10 years. This is a Retrospective cohort study performed in a 3rd level nursery at Santa Joana Maternity Hospital, a fee-paying institution in Sao Paulo, Brazil. From January 1991 to December 2000, 963 live-born infants with a birth weight of 500-1499 g, without congenital anomalies, were followed until discharge. Survival was studied according with year of birth, and stratified by birth weight and gestational age. Factors present at birth associated with survival were analyzed by logistic regression. Patient characteristics were: birth weight 500-999 g (38%), gestational ages or=750 g, and gestational age >or=26 weeks.  相似文献   
107.
The SRY gene (sex-determining region of the Y chromosome) initiates the process of male sex differentiation in mammalians. In humans mutations in the SRY gene have been reported to account for 10-15% of the XY sex reversal cases. We describe here two novel missense mutations in the SRY gene after the screening of 17 patients, including 3 siblings, with 46,XY gonadal dysgenesis and 4 true hermaphrodites. One of the mutations, an A to C transversion within the HMG box, causes the N65H substitution and it was found in a patient presenting 46,XY pure gonadal dysgenesis. The Escherichia coli expressed SRY(N65H) protein did not present DNA-binding activity in vitro. The other mutation, a G to T transversion, causes the R30I substitution. This mutation was found in affected and nonaffected members of a family, including the father, two siblings with partial gonadal dysgenesis, a phenotypic female with pure gonadal dysgenesis, and three nonaffected male siblings. The G to T base change was not found in the SRY sequence of 100 normal males screened by ASO-PCR. The R30I mutation is located upstream to the HMG box, within the (29)RRSSS(33) phosphorylation site. The E. coli expressed SRY(R30I) protein was poorly phosphorylated and consequently showed reduced DNA-binding capacity in vitro.  相似文献   
108.
An 18-year-old woman was evaluated because of primary amenorrhea and hypogonadism. Chromosome analysis from peripheral blood lymphocytes revealed a nonmosaic 46,X,+mar constitution. The marker was shown to be a rearranged Y chromosome consisting of an inverted duplication of the long arm: rea(Y)(qter-q11::q11-qter). Deletion mapping analysis with Y-specific STS showed that the marker lacked Yp and Y-centromeric (DYZ3) sequences, but it was positive for Yq sequences tested. Fluorescence in situ hybridization analysis with Y and X chromosome centromeric and pancentromeric probes showed no hybridization signals. The marker chromosome is present in 100% of the cells; therefore, it is mitotically stable despite the absence of DYZ3 centromeric sequence. Hybridization with CENP-A and CENP-C specific antibodies localized a neocentromere close to the breakpoint.  相似文献   
109.
Patients infected with HIV-1 develop a potent humoral immune response against the virus, but HIV-1 primary isolates are remarkably resistant to neutralizing antibodies. Considering that the envelope glycoprotein of HIV-1 (gp120/41) is heavily glycosylated, we investigated whether anti-carbohydrate antibodies could inhibit HIV-1 infection in vitro. We studied the neutralizing activity of three monoclonal antibodies (mAbs) raised to carbohydrates of Schistosoma mansoni, against seven primary isolates of HIV-1. Assays were performed infecting peripheral blood mononuclear cells from normal donors with viral isolates previously treated with mAbs. Viral strains used were tropic for the coreceptors CCR5, CXCR4, and dual-tropic ones. We found that the anti-glycan mAbs vigorously inhibited HIV-1 infection, regardless of the preferential coreceptor usage of the isolate, in a dose-response manner. Importantly, five isolates were resistant to neutralization by two HIV-1 antibody-positive human sera endowed with potent anti-HIV-1 inhibitory activity. Our findings suggest that carbohydrates of the HIV-1 viral envelope may be a target of an effective humoral immune response elicited by vaccination.The first two authors contributed equally to this work  相似文献   
110.
The DNA polymerase from Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV) was identified and sequenced, and its amino acid sequence was compared with other viral DNA polymerases to identify conserved regions and to reconstruct a phylogenetic tree. The sequence analysis of the AgMNPV DNA polymerase gene revealed the presence of a 2976 nucleotides open reading frame (ORF) encoding a polypeptide of 991 amino acid residues with a predicted molecular mass of 114.7 kDa. Among the baculovirus DNA polymerase genes identified to date, the AgMNPV DNA polymerase gene shared maximum amino acid sequence identity with the DNA polymerase gene of Choristoneura fumiferana nucleopolyhedrovirus defective strain (CfDEFNPV) (94%). The alignment of 140 virus sequences, 23 of them from baculovirus, showed that, of the 10 conserved regions identified, 5 are exclusive to baculoviruses (R1, R5, R9, R6 and R10), only 2 of them (R6 and R10) previously described as such in the literature. Our analysis, based on their positions in the AgMNPV DNA polymerase model, suggests that R9 and R10 could interact with DNA. Phylogenetic analysis of DNA polymerase sequences places the enzyme from AgMNPV within the cluster containing the polymerases of Group I Nucleopolyhedrovirus and suggests that the AgMNPV DNA polymerase is more closely related to that of CfDEFNPV than to those of other baculoviruses.  相似文献   
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