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Elliott AM Evans JA 《Birth defects research. Part A, Clinical and molecular teratology》2008,82(6):425-434
BACKGROUND: Split hand foot malformation (SHFM) (cleft hand, central ray deficiency) is a highly variable malformation that shows genetic heterogeneity with at least five loci mapped to date. SHFM occurs as an isolated finding or in association with other anomalies, including congenital heart defects (CHDs). METHODS: In total 48 SHFM1, 52 SHFM3, 48 SHFM4, 21 SHFM5, and four chromosome 8 patients were evaluated. In addition, we performed a literature review to identify “unmapped” SHFM patients with CHD to evaluate the various etiologies of this combination of findings. The London Dysmorphology Database also served as a resource to identify syndromes with this combination of phenotypic findings. Only patients presenting with both SHFM and CHD were included in the analysis. Classification of CHD among mapped and unmapped SHFM patients was performed utilizing the revised Clark classification. A closer inspection of the types of CHD found in this patient group was performed in order to investigate possible pathogenetic mechanisms. RESULTS: CHDs were found in 10% of SHFM1 patients, 47% of SHFM5 patients, but were not reported in SHFM2, SHFM4 patients, or patients mapped to chromosome 8. Forty‐two syndromic cases and 15 cases of unrecognized syndromes were identified. CONCLUSIONS: The higher frequency of heart defects seen in SHFM1 and SHFM5 of the mapped patient group raises the question as to whether common mechanisms/genetic players are involved. Candidate genes for SHFM1 and SHFM5 include members of the DLX homeobox gene family. Birth Defects Research (Part A), 2008. © 2008 Wiley‐Liss, Inc. 相似文献
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The importance of plant hormones in clubroot infection has long been recognized. The morphological changes, such as cell division and cell elongation leading to gall formation are triggered in the early stages of infection. We analysed cell expansion by localizing Xyloglucan endoTransglucosylase/Hydrolase (XTH)-action and screened the endogenous concentrations of several classes of phytohormones by mass spectrometry in the early stages of Plasmodiophora brassicae infection in Chinese cabbage (Brassica rapa spp. pekinensis). Infected plants showed a general transient growth promotion early in infection. Furthermore a clear XTH action was visible in the epidermal layer of infected roots. Complex changes in the endogenous phytohormone profile were observed. Initially infection resulted in an increased total auxin pool. The auxin increase, together with an increased XTH action, results in wall loosening and consequently cell expansion. When the first secondary plasmodia are formed, thirteen days after infection (DAI), can be considered a switch point in phytohormone metabolism. Twenty-one DAI the plasmodia might act as a plant hormone sink resulting in a reduction in the active cytokinin pool and a lower indole-3-acetic acid content in the infected plants. 相似文献
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Summary. This review has focused on the evidence for the involvement of nitrative oxidation in certain neurodegenerative disorders (Parkinsons Disease, Alzheimers Disease, Amyotrophic Lateral Sclerosis), stroke, and inflammatory and autoimmune disorders (with particular attention devoted to multiple sclerosis).The relationship between protein peroxidation and pathological changes observed in the above disorders has been reported. Whereas many of the findings are from studies with animal models and autoptic specimens from human patients, few data are available from cerebrospinal fluid and blood samples of the patients at different times and disease stages.The participation of nitrative oxidation to the direct and indirect injury of neurons and other cells of the brain (i.e., oligodendrocytes, for multiple sclerosis) is clear; less evident is their relevance for the development and progression of these disorders.Further studies should be aimed to establish the clinical and prognostic value of peroxidative markers for the CNS diseases considered. This is fundamental for the development of therapeutic interventions antagonizing nitric oxide-related species damage. 相似文献
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Tian-lei Zhang Xin-guang Lan Ming-jie Wen Yong-qi Zhang Rui Wang 《Molecular simulation》2013,39(18):1544-1553
ABSTRACTIn this article, we report a theoretical investigation on the role of several catalysts in the isomerisation mechanisms of HON(O)NNO2 to ON(OH)NNO2 by theoretical method of CBS-QB3. The isomerisation reactions with catalyst X (X?=?H2O, (H2O)2, HCOOH and H2SO4) are multi-hydrogen atom transfer reactions. Compared to the isomerisation mechanisms and rate constant of HON(O)NNO2 to ON(OH)NNO2 without catalysts, incorporation of the catalyst X shows different positive catalytic effects on affecting the reaction processes, with the H2SO4-assisted reaction being the most favourable. Such different catalytic effects are mainly related to the size of the ring structure in X-assisted transition states and the different values of pKa and proton affinities for HCOOH and H2SO4. Besides, compared with the barrier height of the isomerisation process from HON(O)NNO2 to ON(OH)NNO2 with HN(NO2)2 and HON(O)NNO2, the barrier of H2SO4-assisted reaction is lower by 9.3 and 4.5?kcal?·mol?1, meanwhile, the rate constant of H2SO4 catalyzed is larger than water and water dimer–assisted by 3–5 and 2–3 orders of magnitude, respectively. So, H2SO4-assisted reaction is the most favourable. 相似文献