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161.
Chromosome 17 markers and von Recklinghausen neurofibromatosis: A genetic linkage study in a British population 总被引:4,自引:0,他引:4
Meena Upadhyaya Mansoor Sarfarazi Susan M. Huson Karen Stephens Wendy Broadhead Peter S. Harper 《Genomics》1987,1(4):358-360
A genetic linkage study of the RFLPs identified by nine DNA probes localized to the pericentromeric region and long arm of chromosome 17 has been undertaken in 16 families with von Recklinghausen neurofibromatosis (NF1). Close linkage has been shown with the markers CRI-L946 (D17S36), CRI-L581 (D17S37), p17H8 (D17Z1), and pA10-41 (D17S71). The ERBA1 and COL1A1 loci may also be closely linked, but the data are limited. The results for HOX2 and NGFR suggest only loose linkage with the NF1 gene, while no linkage was found between NF1 and the growth hormone locus. No suggestion of nonallelic heterogeneity of NF1 was found in this study. 相似文献
162.
Determination of the in vivo redox status of cysteine, cysteinylglycine, homocysteine, and glutathione in human plasma. 总被引:5,自引:0,他引:5
An assay that measures the reduced, oxidized, and protein-bound forms of cysteine, cysteinylglycine, homocysteine, and glutathione in human plasma is described. Oxidized and protein-bound thiols are converted to their reduced counterparts by the use of NaBH4, and, following derivatization with monobromobimane (mBrB), the thiol-bimane adducts are quantified by reversed-phase ion-pair liquid chromatography and fluorescence detection. The presence of 50 microM dithioerythritol provides linearity of the standard curves at very low thiol concentrations. Selective determination of the oxidized forms was accomplished by blocking free sulfhydryl groups with N-ethylmaleimide (NEM) and excess NEM is inactivated by the subsequent addition of NaBH4. The reduced forms of the thiols in plasma were trapped with minimal oxidation by derivatizing blood samples at the time of collection. This was attained by drawing blood directly into tubes containing isotonic solutions of mBrB or NEM. The assay is sufficiently sensitive (less than 2 pmol) to detect the various forms of the four thiol compounds in human plasma. The analytical recovery of cysteine, cysteinylglycine, homocysteine, and glutathione was close to 100%, and the within-day precision corresponded to a coefficient of variation of 7, 8, 6, and 7%, respectively. The assay has been used to determine the various forms of the four thiol compounds in human plasma. 相似文献
163.
Recombination Among Begomoviruses on Malvaceous Plants Leads to the Evolution of Okra Enation Leaf Curl Virus in Pakistan 下载免费PDF全文
Saad Serfraz Imran Amin Khalid P. Akhtar Shahid Mansoor 《Journal of Phytopathology》2015,163(9):764-776
Whitefly transmitted begomoviruses (family Geminiviridae) are the major reason for significant yield losses of dicotyledonous crops in tropics and subtropics. Okra (Abelmoschus esculentus) is one of the important vegetable crops, and leaf curl disease caused by geminiviruses is the most important limiting factor for its production in Pakistan. Here, we report a new species of okra‐infecting begomovirus in south‐eastern region of Pakistan and the name Okra enation leaf curl virus (OELCuV) complex is proposed. This okra enation leaf curl disease complex (OELCuD) in Pakistan is found to be associated with Ageratum conyzoides symptomless alphasatellite (AConSLA). All efforts to clone the betasatellite were unsuccessful. Comprehensive sequence analyses suggest that intermalvaceous recombination between okra and cotton‐infecting begomoviruses resulted in the evolution of the new species. Surprisingly, Bhendi yellow vein mosaic virus (BYVMV) which has not been reported previously from Pakistan is the major parent while Cotton leaf curl Multan virus (CLCuMV) acts as a distant parent of the virus. Comparative recombination analysis also reveals that okra‐infecting begomoviruses from south and north‐western India is causing OELCuD in the Pakistan by recombining with CLCuMV at the Rep (1964–1513 nts). Recombination is common among geminiviruses and recombining of BYVMV and CLCuMV resulted in a new species: OELCuV. To the best of our knowledge, this evolution of a new species of okra‐infecting begomovirus is the first report of intermalvaceous recombination where Rep acts as the target region. 相似文献
164.
Saima Siddiqi Jia Nee Foo Anthony Vu Saad Azim David L. Silver Atika Mansoor Stacey Kiat Hong Tay Sumiya Abbasi Asraf Hussain Hashmi Jamal Janjua Sumbal Khalid E. Shyong Tai Gene W. Yeo Chiea Chuen Khor 《PloS one》2014,9(12)
The diagnosis of childhood neurological disorders remains challenging given the overlapping clinical presentation across subgroups and heterogeneous presentation within subgroups. To determine the underlying genetic cause of a severe neurological disorder in a large consanguineous Pakistani family presenting with severe scoliosis, anarthria and progressive neuromuscular degeneration, we performed genome-wide homozygosity mapping accompanied by whole-exome sequencing in two affected first cousins and their unaffected parents to find the causative mutation. We identified a novel homozygous splice-site mutation (c.3512+1G>A) in the ALS2 gene () encoding alsin that segregated with the disease in this family. Homozygous loss-of-function mutations in ALS2 are known to cause juvenile-onset amyotrophic lateral sclerosis (ALS), one of the many neurological conditions having overlapping symptoms with many neurological phenotypes. RT-PCR validation revealed that the mutation resulted in exon-skipping as well as the use of an alternative donor splice, both of which are predicted to cause loss-of-function of the resulting proteins. By examining 216 known neurological disease genes in our exome sequencing data, we also identified 9 other rare nonsynonymous mutations in these genes, some of which lie in highly conserved regions. Sequencing of a single proband might have led to mis-identification of some of these as the causative variant. Our findings established a firm diagnosis of juvenile ALS in this family, thus demonstrating the use of whole exome sequencing combined with linkage analysis in families as a powerful tool for establishing a quick and precise genetic diagnosis of complex neurological phenotypes. NM_020919.3相似文献
165.
The discrete modeling formalism of René Thomas is a well known approach for the modeling and analysis of Biological Regulatory Networks (BRNs). This formalism uses a set of parameters which reflect the dynamics of the BRN under study. These parameters are initially unknown but may be deduced from the appropriately chosen observed dynamics of a BRN. The discrete model can be further enriched by using the model checking tool HyTech along with delay parameters. This paves the way to accurately analyse a BRN and to make predictions about critical trajectories which lead to a normal or diseased response. In this paper, we apply the formal discrete and hybrid (discrete and continuous) modeling approaches to characterize behavior of the BRN associated with MyD88-adapter-like (MAL)--a key protein involved with innate immune response to infections. In order to demonstrate the practical effectiveness of our current work, different trajectories and corresponding conditions that may lead to the development of cerebral malaria (CM) are identified. Our results suggest that the system converges towards hyperinflammation if Bruton's tyrosine kinase (BTK) remains constitutively active along with pre-existing high cytokine levels which may play an important role in CM pathogenesis. 相似文献
166.
Dharni S Alam M Kalani K Abdul-Khaliq Samad A Srivastava SK Patra DD 《Journal of microbiology and biotechnology》2012,22(5):674-683
A new strain, SD12, was isolated from tannery waste polluted soil and identified as Pseudomonas aeruginosa on the basis of phenotypic traits and by comparison of 16S rRNA sequences. This bacterium exhibited broad-spectrum antagonistic activity against phytopathogenic fungi. The strain produced phosphatases, cellulases, proteases, pectinases, and HCN and also retained its ability to produce hydroxamate-type siderophore. A bioactive metabolite was isolated from P. aeruginosa SD12 and was characterized as 1-hydroxyphenazine ((1-OH-PHZ) by nuclear magnetic resonance (NMR) spectral analysis. The strain was used as a biocontrol agent against root rot and wilt disease of pyrethrum caused by Rhizoctonia solani. The stain is also reported to increase the growth and biomass of Plantago ovata. The purified compound, 1-hydroxyphenazine, also showed broad-spectrum antagonistic activity towards a range of phytopathogenic fungi, which is the first report of its kind. 相似文献
167.
Efficacy of two newly synthesized cry1Ac and cry2Ab genes was checked in tobacco before their expression in cotton. Both genes were artificially synthesized and codon optimized with respect to cotton-preferred codon usage. These genes were cloned in a plant expression vector and then transformed into tobacco. Fifty-eight putative transgenic plants were recovered from the selected explants. Successful integration of both genes in plant genome was confirmed by PCR amplification. Expression of transgenes was confirmed by PCR amplification from total plant RNA. Detached leaf insect bioassays were conducted with Helicoverpa armigera and Spodoptera exigua larvae. About 12 % of the transgenic plants showed significantly high resistance to S. exigua. Significant mortality (62 %) of H. armigera was recorded within 24 h of bioassays. Both toxins showed synergistic effect in tobacco and broadened the spectrum of plant activity against insects. 相似文献
168.
Angara Sureshbabu Mansoor A Syed Chandra Sekhar Boddupalli Madhav V Dhodapkar Robert J Homer Parviz Minoo Vineet Bhandari 《Respiratory research》2015,16(1)
Background
Earlier studies have reported that transforming growth factor beta 1(TGFβ1) is a critical mediator of hyperoxia-induced acute lung injury (HALI) in developing lungs, leading to impaired alveolarization and a pulmonary phenotype of bronchopulmonary dysplasia (BPD). However, the mechanisms responsible for the TGFβ1-induced inflammatory signals that lead to cell death and abnormal alveolarization are poorly understood. We hypothesized that TGFβ1 signaling via TGFβR2 is necessary for the pathogenesis of the BPD pulmonary phenotype resulting from HALI.Methods
We utilized lung epithelial cell-specific TGFβ1 overexpressing transgenic and TGFβR2 null mutant mice to evaluate the effects on neonatal mortality as well as pulmonary inflammation and apoptosis in developing lungs. Lung morphometry was performed to determine the impaired alveolarization and multicolor flow cytometry studies were performed to detect inflammatory macrophages and monocytes in lungs. Apoptotic cell death was measured with TUNEL assay, immunohistochemistry and western blotting and protein expression of angiogenic mediators were also analyzed.Results
Our data reveals that increased TGFβ1 expression in newborn mice lungs leads to increased mortality, macrophage and immature monocyte infiltration, apoptotic cell death specifically in Type II alveolar epithelial cells (AECs), impaired alveolarization, and dysregulated angiogenic molecular markers.Conclusions
Our study has demonstrated the potential role of inhibition of TGFβ1 signaling via TGFβR2 for improved survival, reduced inflammation and apoptosis that may provide insights for the development of potential therapeutic strategies targeted against HALI and BPD. 相似文献169.
170.
In the last decades, extensive research on the effects of nano-TiO2 on plant systems and different microorganisms has confirmed its photocatalytic and antimicrobial activity. However, there is no report on its application in plant cell and tissue culture as well as its role in eliminating contaminating microorganisms in tissue culture. In this work, barley mature embryos were cultured in Murashige and Skoog medium with four concentrations (0, 10, 30, 60???g/ml) of TiO2 suspension in four repetitions. Quantitative and qualitative characteristics of calli were analyzed after each subculture. Data analysis for calli number in the first culture and callus size in all three cultures showed that the effect of treatment was significant at p?>?0.95. As a result, quantitative features such as callus color, shape, embryogenesis, etc. were completely similar in both control and TiO2 nanoparticle treatments; there is no doubt that TiO2 nanoparticles could dramatically increase callugenesis and the size of calli. As well, TiO2 nanoparticles are effective bactericides with an aseptic effect, causing no negative change in the quality of the callus. It is necessary to do more complementary works to identify mechanisms involved for the increased calli size and embryogenesis of explants in darkness. 相似文献