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141.
AC Lidral PA Romitti AM Basart T Doetschman NJ Leysens S Daack-Hirsch EV Semina LR Johnson J Machida A Burds TJ Parnell JL Rubenstein JC Murray 《Canadian Metallurgical Quarterly》1998,63(2):557-568
Nonsyndromic cleft lip with or without cleft palate (CL/P) and nonsyndromic cleft palate only (CPO) are common congenital anomalies with significant medical, psychological, social, and economic ramifications. Both CL/P and CPO are examples of complex genetic traits. There exists sufficient evidence to hypothesize that disease loci for CL/P and CPO can be identified by a candidate-gene linkage-disequilibrium (LD) strategy. Candidate genes for clefting, including TGFA, BCL3, DLX2, MSX1, and TGFB3, were screened for LD with either CL/P or CPO in a predominantly Caucasian population, with both case-control- and nuclear-family-based approaches. Previously reported LD for TGFA with both CL/P and CPO could not be confirmed, except in CL/P patients with a positive family history. Also, in contrast to previous studies, no LD was found between BCL3 and either CL/P or CPO. Significant LD was found between CL/P and both MSX1 and TGFB3 and between CPO and MSX1, suggesting that these genes are involved in the pathogenesis of clefting. In addition, a mutation search in the genes DLX2, MSX1, and TGFB3 was performed in 69 CPO patients and in a subset of the CL/P patients. No common mutations were found in the coding regions of these genes; however, several rare variants of MSX1 and TGFB3 were found that may alter the latters' normal function. These results form the basis for future research, including (a) mutation searches in the MSX1 and TGFB3 genes in Caucasian CL/P patients and (b) extension of the search for MSX1 mutations in CPO patients to the noncoding regions. 相似文献
142.
1. Real time, in vivo microvoltammetric studies were performed, using miniature carbon-based sensors, to concurrently detect norepinephrine (NE) release and serotonin (5-HT) release, in 2 separate electrochemical signals, within CA1 region of hippocampus in the freely moving and behaving, male, Sprague Dawley laboratory rat. 2. Concurrently, four parameters of open-field behavior, i.e. Ambulations, Rearing, Fine Movements and Central Ambulatory behavior (a measure of anxiety reduction behavior), were assayed by infrared photobeam detection. 3. Time course studies showed that the mechanism of action of the triazolobenzodiazepine (TBZD), adinazolam, (Deracyn) is dramatically different from that of the classical benzodiazepine (BZD), diazepam (Valium, i.e., adinazolam increased, whereas diazepam decreased, 5-HT release within CA1 region of hippocampus in the freely moving and behaving rat. 4. Adinazolam initially increased NE release and then decreased NE release in CA1 region of hippocampus in the freely moving and behaving rat whereas diazepam only decreased the electrochemical signal for NE; the decrease in NE produced by adinazolam was greater than the decrease in NE release produced by diazepam. 5. The Behavioral Activity Patterns, derived from same animal controls, simultaneously with detection of in vivo microvoltammetric signals for NE release and 5-HT release, showed that the BZD, diazepam, exhibited more potent sedative properties than did the TBZD adinazolam. 6. Hippocampal 5-HT and NE release effects of the TBZD, adinazolam, concomitant with behavioral effects lends explanation to the dual anxiolytic/antidepressant properties of the TBZDs. 相似文献
143.
Genotoxic stress triggers signalling pathways that either mediate cell killing or protection of affected cells. While induction of p53 is observed for most of the genotoxins, activation of MAPK/SAPK cascades is not a general response. The role of MAPK/SAPK activation on cell fate, seems to be dependent, in some systems, on the balanced response among both cascades. We have here examined the effect of cis and trans-DDP on the activation of ERK and JNK activities. While no significant induction of ERK was observed with the compounds, both of them are able to strongly activate JNK. Trans-DDP response is rapid and transient while the cis-DDP one is slow and persistent. In contrast with the observed nuclear translocation of JNK in response to U.V. light, none of the platinum compounds induces translocation, on the contrary, activation of JNK occurs in both the nuclear and cytoplasmic compartments. Inhibition of tyrosine phosphatases by orthovanadate pretreatment prolongs the time of JNK induction in response to both platinum compounds. The positive modulation of JNK activation correlates with an increase in toxicity that, for cis-DDP corresponds to a tenfold decrease in the IC50. A strong increase in MKP-1 levels was observed only in response to trans-DDP suggesting the involvement of this activity in the downregulation of JNK activity in response to this compound. Altogether the results suggest that the prolonged activation of JNK in response to cis-DDP contributes to cell death induction. 相似文献
144.
CA Porr DS Kronfeld LA Lawrence RS Pleasant PA Harris 《Canadian Metallurgical Quarterly》1998,76(7):1875-1879
Diet and exercise are two management factors that affect bone density and strength. We proposed that bone density and calcium status would be affected by deconditioning for 12 wk and by dietary Ca concentration. Eleven highly conditioned Arabian horses were taken out of training and placed in stalls for 12 wk. Horses were walked on a mechanical walker in two 30-min sessions, 7 d/wk. Diets were designated CC (.36% Ca) and HC (.62% Ca). Data were collected every 21 d. Serum or plasma were analyzed for total and ionized Ca, parathyroid hormone, osteocalcin, hydroxyproline, electrolytes, and blood gases. Bone mineral content (BMC) of the left third metacarpal bone was estimated by radiographic photometry using an aluminum step wedge, which was exposed in each radiograph, as a reference standard for an image analysis system. During deconditioning, BMC decreased by approximately 1.1 g/2 cm, or .45% per week. This decrease was unaffected by dietary Ca. Serum Ca concentration increased with deconditioning. The results suggest that dietary Ca at twice the currently recommended level did not prevent the loss of BMC in response to deconditioning. Loss of BMC during 12 wk of stall confinement may weaken bones, increasing the risk of skeletal injuries when training is resumed. 相似文献
145.
OBJECTIVE: To describe the clinical and serologic findings of 50 antiphospholipid antibody (APA)-positive patients within a retrospective study. METHODS: Measurement of visual acuity, slit-lamp biomicroscopy, tonometry, fundus examination and perimetry. Laboratory tests were performed for detection of APA against thromboplastin and cardiolipin. Antinuclear antibodies (ANA), antibodies to dsDNA, antithyroidal and antiparietal antibodies were also tested. RESULTS: A combination of both transient and permanent visual disturbances was noticed in more than half of the patients. Transient visual disturbances included transient blurred vision, partial defects of the visual fields and amaurosis fugax. The most frequent permanent abnormalities were optic atrophy in 20 patients, due to AION in 9 cases, and disturbances of the choroidal circulation in 17 patients. Fourty-six patients had positive levels of thromboplastin APA; cardiolipin APA were found to be increased in 36 patients. CONCLUSIONS: We did not find a clear correlation between APA activity or the immunoglobulin classes in the individual and the severity of the ocular disease. The benefit from a therapy with the antiplatelet agent acetylsalicylic acid was evident in a reduction of the patients' transient visual disturbances and, in most cases, no further progression of permanent visual field defects was observed. 相似文献
146.
OBJECTIVES: To investigate articular cartilage collagen network, thickness of birefringent cartilage zones, and glycosaminoglycan concentration in macroscopically normal looking knee joint cartilage of young beagles subjected to experimental slowly progressive osteoarthritis (OA). METHODS: OA was induced by a tibial 30 degree valgus osteotomy in 15 female beagles at the age of 3 months. Fifteen sisters were controls. Cartilage specimens were collected seven (Group 1) and 18 months (Group 2) postoperatively. Collagen induced optical path difference and cartilage zone thickness measurements were determined from histological sections of articular cartilage with smooth and intact surface by computer assisted quantitative polarised light microscopy. Volume density of cartilage collagen fibrils was determined by image analysis from transmission electron micrographs and content of glycosaminoglycans by quantitative digital densitometry from histological sections. RESULTS: In the superficial zone of the lateral tibial and femoral cartilage, the collagen induced optical path difference (birefringence) decreased by 19 to 71% (p < 0.05) seven months postoperatively. This suggests that severe superficial collagen fibril network deterioration took place, as 18 months postoperatively, macroscopic and microscopic OA was present in many cartilage areas. Thickness of the uncalcified cartilage increased while the superficial zone became thinner in the same sites. In operated dogs, glycosaminoglycan content first increased (Group 1) in the lateral tibial condyle and then decreased (Group 2) (p < 0.05). CONCLUSION: In this OA model, derangement of the superficial zone collagen network was the probable reason for birefringence reduction. This change occurred well before macroscopic OA. 相似文献
147.
Spontaneous cleavage of the less abundant form of tobacco ringspot virus satellite RNA is readily reversible. Capitalizing on earlier observations by Feldstein and Bruening that small 'mini-monomer' RNAs derived from this molecule and containing little more than covalently attached ribozyme and substrate cleavage products are able to efficiently circularize, we have constructed a series of self-circularizing RNAs of precisely known size. Mixtures of linear and circular RNAs synthesized in vitro and containing 225-1132 nt could be completely resolved using a novel two-dimensional denaturing polyacrylamide gel electrophoresis system. Similar analyses of a complex mixture of coconut cadang-cadang viroid RNAs revealed the presence of relatively large amounts of a previously undescribed 'fast-slow' heterodimeric RNA species in infected palms. Only a single DNA template is required to prepare each pair of circular and linear RNA markers. 相似文献
148.
149.
Artificial insemination using cryopreserved semen is a common management tool of the contemporary livestock producer. However, cryopreservation is detrimental to sperm function and fertility, killing some 50% of the spermatozoa during the process. Prediction of cryopreservation damage from prefreeze samples remains elusive. Computer-automated sperm head morphometry was used in this study to determine the effects of cryopreservation on bovine sperm head morphometry. Semen was collected from 18 bulls and was divided. One portion was extended to 200 x 10(6) sperm/ml and a microscope slide was prepared, while the remaining portion was cryopreserved in a Triscitrate-yolk extender. After thawing, the cryopreserved samples were prepared on microscope slides. All slides were air dried and were stained with hematoxylin and rose bengal. The morphometric dimensions for length, width, width/length, area, and perimeter for a minimum of 200 sperm heads were analyzed from each slide by computer-aided sperm head morphometry analysis, and the mean measurements were recorded. Bull sperm heads were significantly (P < 0.01) smaller in cryopreserved spermatozoa than in the companion extended samples for length (8.56+/-0.07 vs. 8.63+/-0.08 microm), width (4.39+/-0.05 vs. 4.48+/-0.05 microm), area (28.42+/-0.07 vs. 29.14+/-0.08 microm), and perimeter (23.33+/-0.21 vs. 23.70+/-0.23 microm) for all bulls. Width/length was also different (0.513 vs. 0.519). In addition, differences (P < 0.05) were found within 14 of 18 bulls for at least four of the morphometric parameters. The percent change in measures after cryopreservation were correlated (P < or = 0.05) to the variability of the extended sample. Variations in sperm head measurements were lower (P < or = 0.05) in extended samples of the four bulls in which no changes occurred than in extended samples of the remaining 14 bulls. These data suggest that the variability in sperm head measurements of individual bulls, or ejaculates, may be an indicator of sperm cryosurvivability. 相似文献
150.
Three-dimensional gel culture systems represent conditions that mimic the differentiated state of mesenchymal cells in vivo. We examined gel contraction, cell growth, and phenotypic modulation of rabbit arterial SMC in three-dimensional gel culture. The gel contraction rate was dependent on the collagen type; that is, the contraction by freshly isolated SMC was faster and more pronounced in type I collagen than in type III collagen. In contrast, the phenotypic modulation of SMC was independent of collagen type. The major portion of cells in both type I and III collagens with growth factors underwent transition from a contractile (G0 phase) to a synthetic phenotype (G1B phase), but this transition was clearly delayed compared with that on collagens. The cells had hardly begun DNA synthesis in either collagen type and failed to proliferate even after 10 days of culture. These results indicate that collagen type is important in gel contraction by vascular SMC, while the organization of collagen fibrils (two-dimensional vs three-dimensional) is more critical in the phenotypic transition and proliferation of these cells. However, the more specific organization of extracellular matrix than the collagen gel culture system may be necessary to maintain the contractile phenotype of SMC. 相似文献