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101.
Osteopathia striata congenita with cranial sclerosis (OSCS) is a skeletal dysplasia caused by germline deletions of or truncating point mutations in the X‐linked gene WTX (FAM123B, AMER1). Females present with longitudinal striations of sclerotic bone along the long axis of long bones and cranial sclerosis, with a high prevalence of cleft palate and hearing loss. Intellectual disability or neurodevelopmental delay is not observed in females with point mutations in WTX leading to OSCS. One female has been described with a deletion spanning multiple neighbouring genes suggesting that deletion of some neighbouring loci may result in abnormal neurodevelopment. In this cohort of 13 females with OSCS resulting from deletions of WTX, a relationship is observed where deletion of ARHGEF9 and/or MTMR8 in conjunction with WTX results in an additional neurodevelopmental phenotype whereas deletion of ASB12 along with WTX is associated with a good neurodevelopmental prognosis.  相似文献   
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We tested the hypothesis that chronic graft-versus-host disease (GVHD) is due to inadequate thymic function by examining pretransplant serum levels of facteur thymique serique (FTS). Four of five patients with no detectable FTS activity developed chronic GVHD, while one of four with some FTS activity did. Further patient numbers are needed to confirm or reject this hypothesis. We further postulated that chronic GVHD, whatever its cause, involves thymic epithelium as a target organ. When tested 11 mo or more posttransplant, patients with chronic GVHD had lower absolute FTS levels (p less than 0.02) and lower age-corrected levels (p = 0.05) than patients without chronic GHVD. Low values in chronic GVHD were associated with the disease itself and not its therapy. These findings show that thymic epithelial secretory function is impaired in chronic GVHD, and this may in part be responsible for the immunodeficiency characteristic of these patients.  相似文献   
104.
Dominantly acting mutations of the fibroblast growth factor (FGF) receptor 2 (FGFR2) gene have been implicated in various craniosynostosis syndromes. Apert syndrome, characterized in addition by syndactyly of the limbs, involves specific mutations at two adjacent residues, Ser252Trp and Pro253Arg, predicted to lie in the linker region between IgII and IgIII of the FGFR2 ligand-binding domain. We have analysed the interaction of FGF ligands with wild-type and Apert- type mutant FGFR2 ectodomains in solution. Wild-type and Apert-type receptors form a complex with FGF ligands with a stoichiometry of 2:2 (ligand:receptor). The kinetics and specificity of ligand binding to wild-type and Apert mutant receptors have been analysed using surface plasmon resonance techniques. This reveals that Apert mutations, compared with wild-type, exhibit a selective decrease in the dissociation kinetics of FGF2, but not of other FGF ligands examined. In contrast, the substitution Ser252Leu in FGFR2, previously observed in several asymptomatic individuals, exhibited wild-type kinetics. These findings indicate that Apert syndrome arises as a result of increased affinity of mutant receptors for specific FGF ligands which leads to activation of signalling under conditions where availability of ligand is limiting.   相似文献   
105.
Low-dose antiprogestin administration has been proposed as a new contraceptive modality to interference with endometrial receptivity without disturbing ovarian function. The effects of 1 mg/day mifepristone for 150 days on the menstrual cycle were assessed in 21 surgically sterilized women. The aim was to study each woman for one control cycle and during months 1, 3 and 5 of treatment. Ovulation, endometrial thickness, serum oestradiol and progesterone, urinary luteinizing hormone, endometrial morphology and cervical mucus were assessed. Luteal phase progesterone concentrations were observed in 36 of the 60 treated months assessed and less frequently as treatment progressed. The bleeding pattern was regular in most biphasic cycles, while prolonged interbleeding intervals or no bleeding were associated with monophasic cycles. Altered endometrial morphology was found in all cases irrespective of the occurrence of luteal activity. Increased endometrial thickness and dilated glands were observed in 25 and 34% respectively of the monophasic cycles. Mifepristone, 1 mg/day, interferes with endometrial development while allowing the occurrence of biphasic ovarian cycles and regular bleeding. However, it also prevents ovarian cyclicity in a high proportion of treated months, and this is associated with increased endometrial growth in some women, which may be of concern.   相似文献   
106.

Background  

Few studies of miners have been carried out in African countries; most are from South Africa, where the working conditions are assumed to be better than in the rest of Africa. Several studies have focused on respiratory disorders among miners, but development workers responsible for creating underground road ways have not been studied explicitly. This is the first study assessing the associations between exposure to dust and quartz and respiratory symptoms among coal mine workers in a manually operated coal mine in Tanzania, focusing on development workers, as they have the highest exposure to coal dust.  相似文献   
107.
X-linked severe combined immunodeficiency (XSCID) is characterized by absent or profoundly reduced numbers of T cells and normal numbers of B cells in the circulation. Affected patients have mutations of the interleukin-2 (IL-2) receptor gamma chain gene. Using Epstein-Barr virus-transformed B-lymphoblastoid cell lines (B-LCLs) established from two unrelated XSCID patients, we could show that neither expressed the IL-2 receptor gamma chain on the cell surface. A novel cytokine IL-15, which has biologic activities similar to those of IL-2, could bind to the XSCID B-LCLs in the absence of the gamma chain, although both the beta and gamma chains of the human IL-2 receptor were previously shown to be required for IL-15 binding by transfected COS cells. Furthermore, a significant reduction and delay of IL-15 internalization by B lymphoblasts from XSCID patients was observed when compared with that of normal control B-LCLs. These results show the existence of a novel IL-15-specific receptor component that contributes to IL-15 binding but is insufficient for IL-15 internalization in the absence of the IL-2 receptor gamma chain.  相似文献   
108.
Price  TH; Ochs  HD; Gershoni-Baruch  R; Harlan  JM; Etzioni  A 《Blood》1994,84(5):1635-1639
We investigated in vivo neutrophil and lymphocyte function in a patient who lacks Sialyl-Lewis-X, a ligand for the selectin family of leukocyte adhesion molecules (leukocyte adhesion deficiency II, LAD II). As assessed by skin chamber and skin window techniques, in vivo chemotaxis of neutrophils was markedly impaired (less than 6% of normal values). A marginal pool was present as determined by an increase in circulating neutrophils after epinephrine injection and calculated recovery of infused radiolabeled autologous neutrophils. Kinetic studies showed a reduced half-life of 3.2 hours (normal 7 hours) and markedly increased turnover rate (cells/kg/d) of approximately eight times the normal value. A normal antibody response to the T-cell-dependent antigen bacteriophage phi X174 showed that T/B-cell interaction is not affected in LAD II. These findings provide direct evidence that the selectin family and its ligands play an important role in neutrophil function.  相似文献   
109.
Cognitive dysfunction is central to Huntington's disease (HD) and undermines quality of life. Clinical trials are now targeting cognitive outcomes in HD; however, no cognitive battery has been optimized for HD clinical trials. We evaluated 16 cognitive tests in a 20‐site, five‐country, observational study designed to mimic aspects of a clinical trial (e.g., data collection managed by a contract research organization, repeated testing, prespecified statistical analyses). Fifty‐five early HD, 103 premanifest HD (pre‐HD), and 105 controls were tested at visit 1, visit 2 (1‐3 days later), and visit 3 (5‐7 weeks after visit 1). For inclusion in a recommended battery, tests were evaluated for sensitivity, practice effects, reliability, domain coverage, feasibility, and tolerability. Most tests differentiated controls from pre‐HD and early HD and showed excellent psychometric properties. We selected six tests to constitute the Huntington's Disease Cognitive Assessment Battery (HD‐CAB): Symbol Digit Modalities Test, Paced Tapping, One Touch Stockings of Cambridge (abbreviated), Emotion Recognition, Trail Making B, and the Hopkins Verbal Learning Test. These tests demonstrated sensitivity to disease status (Cohen's d effect sizes: early HD= ?1.38 to ?1.90 and pre‐HD= ?0.41 to ?0.78), and acceptable reliability (r's 0.73‐0.93). A composite score yielded large effect sizes (early HD = ?2.44 and pre‐HD = ?0.87) and high reliability (r = 0.95). HD‐CAB is the first cognitive battery designed specifically for use in late premanifest and early HD clinical trials. Adoption of the HD‐CAB will facilitate evaluation of treatments to improve cognition in HD. © 2014 International Parkinson and Movement Disorder Society  相似文献   
110.
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