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81.
Teppei Moriwaki Yujirou Yamamoto Takehiko Aida Tatsuya Funahashi Toshiyuki Shishido Masataka Asada Shamusul Haque Prodhan Atsushi Komamine Tsuyoshi Motohashi 《Plant biotechnology reports》2008,2(1):41-46
Salinity stress is a major limiting factor in cereal productivity. Many studies report improvements in salt tolerance using
model plants, such as Arabidopsis thaliana or standard varieties of rice, e.g., the japonica rice cultivar Nipponbare. However, there are few reports on the enhancement
of salt tolerance in local rice cultivars. In this work, we used the indica rice (Oryza sativa) cultivar BR5, which is a local cultivar in Bangladesh. To improve salt tolerance in BR5, we introduced the Escherichia coli catalase gene, katE. We integrated the katE gene into BR5 plants using an Agrobacterium tumefaciens-mediated method. The introduced katE gene was actively expressed in the transgenic BR5 rice plants, and catalase activity in T1 and T2 transgenic rice was approximately 150% higher than in nontransgenic plants. Under NaCl stress conditions, the transgenic
rice plants exhibited high tolerance compared with nontransgenic rice plants. T2 transgenic plants survived in a 200 mM NaCl solution for 2 weeks, whereas nontransgenic plants were scorched after 4 days
soaking in the same NaCl solution. Our results indicate that the katE gene can confer salt tolerance to BR5 rice plants. Enhancement of salt tolerance in a local rice cultivar, such as BR5, will
provide a powerful and useful tool for overcoming food shortage problems. 相似文献
82.
The mangrove forest of Bangladesh, the largest continuous mangrove forest of the world, is one of the most important coastal features of the country. The existence of the mangrove has increased the values of other coastal and marine resources such as the coastal and marine fisheries by increasing productivity and supporting a wide biological diversity. The artisanal fishery, which is highly influenced by mangroves, has been contributing 85–95% of the total coastal and marine catch of Bangladesh. The mangrove also supports offshore and deep sea fisheries by playing a significant role as nursery ground for many deep sea fishes and shrimps including the giant tiger shrimp (Penaeus monodon) which is the major species of the industrial bottom trawl fishery of Bangladesh. The mangrove also contributes significantly in shrimp farming which has been the most significant export-oriented industry since the 1970s. However, the mangrove fisheries have been under intensive pressure from deleterious fishing activities and deliberate aquaculture development by destructing mangrove habitats. The impacts of mangrove have been reflected in the contribution of artisanal fishery catch that has been in a continuous decline since the 1980s. Shrimp farming has been the most destructive contributor to mangrove destruction with a corresponding loss of biological resources particularly the wild shrimp fishery. This paper reviews different aspects of the mangrove fisheries of Bangladesh and discusses the impacts of different fisheries. The paper identifies the importance of reviewing, amending and/or replacing the traditional management approaches by the new management techniques such as habitat restoration and stock enhancement in the natural environment; the paper also identifies the need for research findings in formulating and implementing new management approaches. 相似文献
83.
Jean-Paul Cimma Josiane Arnaud Jos Labarere Olivier Guillard Frdrique Nugues Annie Marrauld Chantal Durand Jean-Marie Farvacque Serge Pierre Bottari Shahidul Haque 《Journal of trace elements in medicine and biology》2004,17(4):249-253
The putative role of aluminium intake in young Bangladeshi children (1.5 to 4 years of age) with calcium-deficient rickets was evaluated in a non randomised controlled eight month trial. The effects of aluminium or stain-less-steel cooking pots on bone metabolism were assessed by measuring blood calcium, phosphorus, alkaline phosphatase, parathyroid hormone, 1,25 dihydroxy vitamin D, aminoterminal propeptide of type 1 collagen (PINP), cross-linked carboxyterminal telopeptide of type 1 collagen (ICTP), aluminium and albumin, and by analysis of wrist radiographs. In both groups, blood alkaline phosphatase, 1,25 dihydroxy vitamin D and aluminium decreased significantly, while serum albumin increased (p < 0.01). These results suggest that the nutrition may well be of major importance, whereas the role of aluminium appears to be insignificant. 相似文献
84.
K Kitajima M Haque H Nakamura T Hirano H Utiyama 《Biochemical and biophysical research communications》2001,288(5):1182-1187
The human HL-60 acute leukemia cell line harbors double minutes (dmins) during early passages. During its continuous culture for a long term, a single marker chromosome with a homogeneously staining region (HSR) replaces the dmins. The both structures harbor amplified c-MYC sequences. Here we ask how the cellular phenotype is altered by the c-MYC integration into a HSR. Treatment with dimethyl sulfoxide induces granulocytic differentiation in the both types of cells. In contrast to HL-60/dmin cells, however, no apoptosis followed differentiation and the differentiation phenotype was reverted upon withdrawal of the drug in HL-60/HSR cells. Terminal differentiation and loss of DNase I hypersensitivity sites at c-MYC P2 promoter appeared to be unlinked in the both types of cells. By comparison with HL-60/dmin cells, we conclude that the integration into a HSR of an extrachromosomal gene(s) but not c-MYC likely leads to the loss of irreversibility of the differentiation phenotype. 相似文献
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88.
Environmentally induced epigenetic transgenerational inheritance of disease and phenotypic variation involves germline transmitted epimutations. The primary epimutations identified involve altered differential DNA methylation regions (DMRs). Different environmental toxicants have been shown to promote exposure (i.e., toxicant) specific signatures of germline epimutations. Analysis of genomic features associated with these epimutations identified low-density CpG regions (<3 CpG / 100bp) termed CpG deserts and a number of unique DNA sequence motifs. The rat genome was annotated for these and additional relevant features. The objective of the current study was to use a machine learning computational approach to predict all potential epimutations in the genome. A number of previously identified sperm epimutations were used as training sets. A novel machine learning approach using a sequential combination of Active Learning and Imbalance Class Learner analysis was developed. The transgenerational sperm epimutation analysis identified approximately 50K individual sites with a 1 kb mean size and 3,233 regions that had a minimum of three adjacent sites with a mean size of 3.5 kb. A select number of the most relevant genomic features were identified with the low density CpG deserts being a critical genomic feature of the features selected. A similar independent analysis with transgenerational somatic cell epimutation training sets identified a smaller number of 1,503 regions of genome-wide predicted sites and differences in genomic feature contributions. The predicted genome-wide germline (sperm) epimutations were found to be distinct from the predicted somatic cell epimutations. Validation of the genome-wide germline predicted sites used two recently identified transgenerational sperm epimutation signature sets from the pesticides dichlorodiphenyltrichloroethane (DDT) and methoxychlor (MXC) exposure lineage F3 generation. Analysis of this positive validation data set showed a 100% prediction accuracy for all the DDT-MXC sperm epimutations. Observations further elucidate the genomic features associated with transgenerational germline epimutations and identify a genome-wide set of potential epimutations that can be used to facilitate identification of epigenetic diagnostics for ancestral environmental exposures and disease susceptibility. 相似文献
89.
Measurements were made of the differences between sunflower and climbing hempweed leaves for development, fecundity and egg hatchability of Diacrisia casignetum Kollar. Developmental time and weight gains of sunflower-fed larvae were respectively longer and greater than those of hempweed-fed ones. The development time and weight gain, attributable to differences in host plants, were statistically heterogeneous (P<0.05-<0.10). Relative fecundity and egg hatchability of sunflower reared insects were greater than those of hempweed reared ones, and these were also statistically heterogeneous (P<0.1 and <0.05, respectively). Hempweed leaves contained relatively high titres of phenols and low ratios of proteins to phenols. Ovaries were heavier in insects reared on sunflower than on hempweed, whereas the level of phenols incorporated into the ovary was higher in insects fed on hempweed than those on sunflower. The differences in these parameters may be due to variations in nutritional quality of these hosts and incorporation of ingested phenolic materials to ovary and insect biomass.
Résumé L'étude a porté sur l'évaluation de l'influence des feuilles de tournesol (Helianthus annuus) et de Mikana cordata sur le développement, la fécondité et l'éclosion des oeufs de D. casignetum Kollaz. La durée de développement et le gain de poids sur tournesol étaient plus importants que sur M. cordata. La durée de développement était statistiquement hétérogène (P<0.05), ce qui peut être dû à des différences entre plantes. La fécondité et le taux d'éclosion chez les insectes élevés sur tournesol étaient plus élevés que ceux observés sur M. cordata, dont les résultats étaient aussi hétérogènes (P<0.1 et<0.05 respectivement). Les feuilles de M. cordata contenaient des taux relativement élevés de phénols et des rapports protéines sur phénols bas. Tout ceci suggère que les différences observées sont attribuables à des variations dans la qualité nutritive de ces hôtes et dans l'incorporation à la biomasse de l'insecte de matériaux phénologiques ingérés.相似文献
90.
Identification of staphylococcal epsilon hemolysin 总被引:2,自引:0,他引:2