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91.
Dystrophic epidermolysis bullosa is a rare blistering condition caused by mutations in the COL7A1 gene. Different clinical variants have been described, with dominant and recessive inheritance, but no consistent findings have been elucidated to establish a genotype–phenotype correlation. We present three unrelated patients with two identical pathogenic compound heterozygous mutations in the COL7A1 gene that developed different clinical forms of dystrophic epidermolysis bullosa—epidermolysis bullosa pruriginosa and mild recessive non‐Hallopeau–Siemens—raising the possibility of other genetic or environmental modifying factors responsible for the phenotype of the disease.  相似文献   
92.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
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The immunogenicity and protective efficacy of recombinant lumazine synthase from Brucella spp. (rBLS) administered with different adjuvants was evaluated in mice. Mice were immunized with rBLS in the absence or the presence of aluminum hydroxide gel (BLS-Al), monophosphoryl lipid A (BLS-MPA), or incomplete Freund's adjuvant (BLS-IFA). rBLS per se induced a vigorous immunoglobulin G (IgG) response, with high titers of IgG1 as well as IgG2. All the adjuvants increased this response; the BLS-IFA formulation was the most effective at inducing BLS-specific IgG antibodies. In addition, after in vitro stimulation with rBLS, spleen cells from BLS-IFA-, BLS-Al-, or BLS-MPA-immunized mice proliferated and produced interleukin-2 (IL-2), gamma interferon (IFN-gamma), IL-10, and IL-4, suggesting the induction of a mixed Th1-Th2 response. Immunization with rBLS protected mice against challenge with B. abortus 544. The levels of protection in the spleen were similar for all adjuvants, but only BLS-Al and BLS-IFA were effective in the liver. Our results indicate that BLS might be a useful candidate for the development of subunit vaccines against brucellosis, since it elicits antigen-specific cellular responses, with production of IFN-gamma and protection, independently of the adjuvant formulation used.  相似文献   
96.
Williams or Williams-Beuren syndrome (WBS) is a developmental disorder with multisystemic manifestations characterized by distinctive facial features, mental disability with unique cognitive and personality profiles, vascular stenoses, growth retardation, and occasional infantile hypercalcemia, caused by haploinsufficiency for genes deleted in chromosome band 7q11.23. However, with the exception of arterial stenoses caused by haploinsufficiency for the elastin gene (ELN), no specific implication of any other gene in the phenotype has been established. We present two patients with portal hypertension leading to splenomegaly and pancytopenia carrying the common 1.5 Mb WBS deletion. We propose this is an additional severe vascular complication of ELN deficiency and discuss the specific characteristics of the portal venous tract that could explain the impact of ELN deficiency in that venous territory. This complication is potentially lethal and should thus be considered in any patient with WBS and splenomegaly.  相似文献   
97.
To evaluate the prognostic significance of submicroscopic deletions of the ABL or BCR gene associated with t(9;22) in chronic myelogenous leukemia (CML), we investigated the incidence of an ABL or BCR deletion on derivative chromosome 9 using fluorescence in situ hybridization (FISH). FISH was performed using the LSI BCR/ABL dual-fusion translocation probe on bone marrow cells of 86 patients with CML. Of 86 patients, ABL deletion was detected in 13 (15.1%) patients and BCR deletion in 8 patients (9.3%). Patients with ABL deletion showed shorter event-free survival time (EFS) than those without ABL deletion (P = 0.020). Patients with BCR deletion showed significantly short overall survival time (OS; P = 0.039). Patients with ABL and/or BCR deletion (14/86 patients, 16.3%) showed significantly short OS and EFS (median OS, 43.0 months; median EFS, 40.0 months), compared to the patients without any BCR or ABL gene deletions (median OS, 94.0 months; median EFS, 90.0 months; P = 0.041 for OS, P = 0.008 for EFS). All the patients with BCR deletion, except for one, had a concomitant ABL deletion, suggesting that BCR deletion occurs in conjunction with ABL deletion. In patients with ABL deletion only, BCR/ABL rearrangement with b2a2 mRNA type tended to be more frequent than in patients without any deletion of the two genes (P = 0.073). Deletion of any of the BCR or ABL genes on derivative chromosome 9 was associated with both short OS and EFS. We conclude that deletion of not only the ABL gene, but also of the BCR gene, is a poor prognostic marker that indicates rapid disease progression in CML.  相似文献   
98.
Nine new unrelated patients presenting vacuolating myelinopathy with subcortical cysts were identified and analyzed for variations in the MLC1 gene. We detected 12 mutations (p.Leu37fs, p.Met80Val, p.Leu83Phe, p.Pro92Ser, p.Ser93Leu, p.Ile108fs, p.Gly130Arg, p.Cys171fs, p.Glu202Lys, p.Ser269Tyr, p.Ala275Asn, and p.Leu310_311insLeu) of which nine were novel. In one patient we did not detect mutations. Using a heterologous system, three new missense variants (p.Glu202Lys, p.Ser269Tyr, and p.Ala275Asn) and a single leucine insertion (p.Leu310insLeu)--lying in a stretch of seven leucines--were functionally assayed by determining total protein levels and mutant protein expression at the plasma membrane. No correlation was observed between mutation, clinical features, and plasma membrane expression of mutant protein.  相似文献   
99.
In some species including rats, mice, gerbils, and rams, apparently normal males fail to copulate when repeatedly tested with receptive females. These animals are called "noncopulators (NC)," and the cause of this behavioral deficit is unknown. It has been shown that NC rats do not have hormonal alterations or deficits in the mechanisms that control penile function. The present study was designed to examine (Experiment 1) whether NC male rats prefer receptive females to sexually active males. In addition, the olfactory preference for bedding soiled from estrous or for anestrous bedding was investigated. These tests were performed in NC and copulating (C) male rats when the subjects were intact, gonadectomized (GDX), or GDX and treated with high doses of testosterone propionate (TP). Our results demonstrate that NC rats do not display sexual behavior even after high TP treatment. While C male rats have a clear preference for receptive females as opposed to a sexually active male, NC rats do not. In all hormonal conditions, the preference shown by NC rats for estrous bedding was significantly reduced in comparison to that seen in C rats. TP treatment in NC rats did not modify either partner or odor preference. In Experiment 2, we evaluated if NC rats are feminized and if it could be easier to induce feminine-like behavior by hormone treatment with estradiol benzoate (EB) or with EB plus progesterone (P) (EB+P). Odor preference for estrous or male bedding under these hormonal conditions was also compared. No differences between NC and C rats were found in feminine sexual behavior. In the olfactory test, we found that NC rats prefer odors from receptive females as opposed to male odors, but this preference is reduced compared to that of C rats. Males treated with EB or EB+P show no preference for female odors. These results demonstrate that treatment with EB or EB+P does not increase feminine sexual behavior in NC rats.  相似文献   
100.
Connective tissue growth factor (CCN2/CTGF) is a matricellular protein that is overexpressed in progressive human renal diseases, mainly in fibrotic areas. In vitro studies have demonstrated that CCN2 regulates the production of extracellular matrix (ECM) proteins and epithelial–mesenchymal transition (EMT), and could therefore contribute to renal fibrosis. CCN2 blockade ameliorates experimental renal damage, including diminution of ECM accumulation. We have reported that CCN2 and its C‐terminal degradation product CCN2(IV) bind to epidermal growth factor receptor (EGFR) to modulate renal inflammation. However, the receptor involved in CCN2 profibrotic actions has not been described so far. Using a murine model of systemic administration of CCN2(IV), we have unveiled a fibrotic response in the kidney that was diminished by EGFR blockade. Additionally, in conditional CCN2 knockout mice, renal fibrosis elicited by folic acid‐induced renal damage was prevented, and this was linked to inhibition of EGFR pathway activation. Our in vitro studies demonstrated a direct effect of CCN2 via the EGFR pathway on ECM production by fibroblasts and the induction of EMT in tubular epithelial cells. Our studies clearly show that the EGFR regulates CCN2 fibrotic signalling in the kidney, and suggest that EGFR pathway blockade could be a potential therapeutic option to block CCN2‐mediated profibrotic effects in renal diseases. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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