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91.
Molybdenum cofactor (Moco)-deficiency is a lethal autosomal recessive disease, for which until now no effective therapy is available. The biochemical hallmark of this disorder is the inactivity of the Moco-dependent sulfite oxidase, which results in elevated sulfite and diminished sulfate levels throughout the organism. In humans, Moco-deficiency results in neurological damage, which is apparent in untreatable seizures and various brain dysmorphisms. We have recently described a murine model for Moco-deficiency, which reflects all enzyme and metabolite changes observed in the patients, and an efficient therapy using a biosynthetic precursor of Moco has been established in this animal model. We now analyzed these mice in detail and excluded morphological brain damage, while expression analysis with microarrays indicates a massive cell death program. This neuronal damage appears to be triggered by elevated sulfite levels and is ameliorated in affected embryos by maternal clearance.  相似文献   
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The activity of the homeobox gene Prox1 is necessary and sufficient for venous blood endothelial cells (BECs) to acquire a lymphatic endothelial cell (LEC) fate. We determined that the differentiated LEC phenotype is a plastic, reprogrammable condition that depends on constant Prox1 activity for its maintenance. We show that conditional down-regulation of Prox1 during embryonic, postnatal, or adult stages is sufficient to reprogram LECs into BECs. Consequently, the identity of the mutant lymphatic vessels is also partially reprogrammed as they acquire some features typical of the blood vasculature. siRNA-mediated down-regulation of Prox1 in LECs in culture demonstrates that reprogramming of LECs into BECs is a Prox1-dependent, cell-autonomous process. We propose that Prox1 acts as a binary switch that suppresses BEC identity and promotes and maintains LEC identity; switching off Prox1 activity is sufficient to initiate a reprogramming cascade leading to the dedifferentiation of LECs into BECs. Therefore, LECs are one of the few differentiated cell types that require constant expression of a certain gene to maintain their phenotypic identity.  相似文献   
95.
The gold standard for bone substitution is the autologous bone graft, but because of its limited supply and the associated morbidity, the search for synthetic alternatives is necessary. A new in situ setting tricalcium phosphate cement was implanted in a trepanation defect (9.4 mm diameter, 10 mm depth) in the distal femoral epiphysis of sheep. Empty cavities and autologous bone graft were used as controls. Histologic and histomorphometric examinations were carried out after 12 weeks. Nearly 90% of the implanted cement was resorbed and replaced by ingrown bone with close contact between surrounding bone, new bone, and remaining cement particles. The amount of bone in the defect area was significantly higher in defects filled with cement relative to defects filled with autologous bone graft (mean 27 vs. 21%, 95% confidence intervals 23 to 31 and 18 to 23, p = 0.026). In conclusion, this new in situ setting cement is bioactive, resorbable, and osteoconductive. It will be useful as an alternative to autologous bone graft to fill stable defects.  相似文献   
96.
We describe two unrelated patients with cytogenetically visible deletions of 21q22.2-q22.3 and mild phenotypes. Both patients presented minor dysmorphic features including thin marfanoid build, facial asymmetry, downward-slanting palpebral fissures, depressed nasal bridge, small nose with bulbous tip, and mild mental retardation (MR). FISH and molecular studies indicated common deleted areas but different breakpoints. In patient 1, the breakpoint was fine mapped to a 5.2 kb interval between exon 5 and exon 8 of the ETS2 gene. The subtelomeric FISH probe was absent on one homologue 21 indicating a terminal deletion spanning approximately 7.9 Mb in size. In patient 2, the proximal breakpoint was determined to be 300-700 kb distal to ETS2, and the distal breakpoint 2.5-0.3 Mb from the 21q telomere, indicating an interstitial deletion sized approximately 4.7-7.3 Mb. The 21q- syndrome is rare and typically associated with a severe phenotype, but different outcomes depending on the size and location of the deleted area have been reported. Our data show that monosomy 21q of the area distal to the ETS2 gene, representing the terminal 7.9 Mb of 21q, may result in mild phenotypes comprising facial anomalies, thin marfanoid build, and mild MR, with or without signs of holoprosencephaly.  相似文献   
97.
There are two forms of diabetes insipidus, central (neurohypophyseal), and nephrogenic, caused by pathogenic variants in the AVP gene and the AVPR2 or AQP2 genes, respectively. We report on a four‐generation family, seven individuals had central diabetes insipidus (CDI) and the female index patient seen from age 16 to 26 years had (mild) nephrogenic diabetes insipidus. In her father with CDI, a known pathogenic heterozygous AVP variant c.232_234del p.(Glu78del) was identified, confirming the diagnosis of CDI in him and the other affected family members. In the proband, molecular analysis disclosed a novel heterozygous AVPR2 gene variant, c.962A > T p.(Asn321Ile) and an extremely skewed X‐inactivation, confirming X‐linked nephrogenic diabetes insipidus (XL‐NDI). Whole exome sequencing showed no further causative mutation. This is the first report on the co‐existence of CDI and NDI in one family. Our review of symptomatic female AVPR2 heterozygotes includes 23 families with at least one affected female (including this study). There were 21 different causative mutations. Mutation types in females did not differ from those in males. Both severe XL‐NDI and mild forms were reported in females. All six females with severe XL‐NDI had complete loss‐of‐function (null) mutations. The remaining 17 female probands had milder XL‐NDI caused by 14 missense variants and three null variants of the AVPR2 gene. X‐inactivation was studied in nine of these females; all showed extreme or slight skewing. The review underlines that XL‐NDI in female AVPR2 heterozygotes is always accompanied by skewed X‐inactivation, emphasizing a need for X‐inactivation studies in these females.  相似文献   
98.
Neuropeptides are the mediators of neurogenic inflammation. Some pain disorders, e.g. complex regional pain syndromes, are characterized by increased neurogenic inflammation and by exaggerated sudomotor function. The aim of this study was to explore whether neuropeptides have a peripheral effect on human sweating. We investigated the effects of different concentrations of calcitonin gene-related peptide (CGRP), vasoactive intestinal peptide (VIP) and substance P (SP) on acetylcholine-induced axon reflex sweating in healthy subjects (total n = 18). All substances were applied via dermal microdialysis. The experiments were done in a parallel setting: ACh alone and ACh combined with CGRP, VIP or SP in various concentrations were applied. Acetylcholine (10−2 m ) always elicited a sweating response, neuropeptides alone did not. However, CGRP significantly enhanced ACh-induced sweating ( P < 0.01). Post hoc tests revealed that CGRP in physiological concentrations of 10−7–10−9 m was most effective. VIP at any concentration had no significant effect on axon reflex sweating. The duration of the sweating response ( P < 0.01), but not the amount of sweat, was reduced by SP. ACh-induced skin blood flow was significantly increased by CGRP ( P < 0.01), but unaltered by VIP and SP. The results indicate that CGRP amplifies axon reflex sweating in human skin.  相似文献   
99.
The Community Placement Scale (CPS), an abbreviated form of the Community Competence Scale (Anderten, 1979) suitable for placement of deinstitutionalized mental patients in the community, was developed in a combined sample of 87 subjects placed in the community in California and Missouri. Although the Community Competence Scale has shown considerable promise as a placement instrument with the deinstitutionalized mentally ill, a briefer measure is needed in order to increase acceptance by both patients and professional staff. Other improvements sought were determining the acceptability of items to placement personnel nationwide, eliminating nondiscriminating items, and heightening internal consistency reliability of subscales. In a series of discriminant analyses, remaining subscales were used to predict community placement with minimal and maximal degrees of structure. From these analyses, a measure that consisted of 5 subscales and 41 items and required approximately 20 minutes to administer was selected. This short form has many similarities to and a few important differences from the previously published short form.  相似文献   
100.
Evidence for specific protein-protein interactions is increasingly available from both small- and large-scale studies, and can be viewed as a network. It has previously been noted that errors are frequent among large-scale studies, and that error frequency depends on the large-scale method used. Despite knowledge of the error-prone nature of interaction evidence, edges (connections) in this network are typically viewed as either present or absent. However, use of a probabilistic network that considers quantity and quality of supporting evidence should improve inference derived from protein networks. Here we demonstrate inference of membership in a partially known protein complex by using a probabilistic network model and an algorithm previously used to evaluate reliability in communication networks.  相似文献   
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