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811.
Tung Hoang Thanh Suong Pham Thi Khai Hoang Dac Luan Vu Quoc Cuong Do Manh Hien Vu Thi Nam Nguyen Ba Ngan Ha Thi My Bien Le The Phong Truong Hoai Nhut Duong Tan 《In vitro cellular & developmental biology. Plant》2022,58(1):70-79
In Vitro Cellular & Developmental Biology - Plant - In this study, a new method for shoot regeneration via protocorm-like bodies (PLBs) is described. Shoot proliferation using stem elongation... 相似文献
812.
G.L. Adessi C. Goutte-Coussieu Tran Quang Nhuan D. Eichenberger M.F. Jayle 《Steroids》1978,32(3):295-306
Different cellular fractions of guinea-pig placenta were incubated in the presence of (7n-3H) testosterone. Microsomal aromatization of 3H-testosterone into estrone and estradiol-17β was demonstrated in the presence of NADPH. The predominance of estrone after incubation with 17β-hydroxylated precursors, (7n-3H) testosterone and (6,7-3H) estradiol-17β, indicate that there is a microsomal 17β-hydroxysterold dehydrogenase activity. In this report, cytosolic sulfurylation of estrogens is demonstrated. This latter activity represents a quite original characteristic of the placental metabolism of estrogens in guinea-pigs. In contrast with the human placenta where there is considerable sulfatase activity, the guinea-pig placenta can sulfurylate estrogens. 相似文献
813.
Anne D. Jungblut Frédéric Raymond Moïra B. Dion Sylvain Moineau Vani Mohit Guillaume Quang Nguyen Maxime Déraspe Élina Francovic-Fontaine Connie Lovejoy Alexander I. Culley Jacques Corbeil Warwick F. Vincent 《Environmental microbiology》2021,23(6):2955-2968
Nostoc (Nostocales, Cyanobacteria) has a global distribution in the Polar Regions. However, the genomic diversity of Nostoc is little known and there are no genomes available for polar Nostoc. Here we carried out the first genomic analysis of the Nostoc commune morphotype with a recent sample from the High Arctic and a herbarium specimen collected during the British Arctic Expedition (1875–76). Comparisons of the polar genomes with 26 present-day non-polar members of the Nostocales family highlighted that there are pronounced genetic variations among Nostoc strains and species. Osmoprotection and other stress genes were found in all Nostoc strains, but the two Arctic strains had markedly higher numbers of biosynthetic gene clusters for uncharacterised non-ribosomal peptide synthetases, suggesting a high diversity of secondary metabolites. Since viral–host interactions contribute to microbial diversity, we analysed the CRISPR-Cas systems in the Arctic and two temperate Nostoc species. There were a large number of unique repeat-spacer arrays in each genome, indicating diverse histories of viral attack. All Nostoc strains had a subtype I-D system, but the polar specimens also showed evidence of a subtype I-B system that has not been previously reported in cyanobacteria, suggesting diverse cyanobacteria–virus interactions in the Arctic. 相似文献
814.
Seo-Hee Kim Quang Luu Quoc Hae-Sim Park Yoo Seob Shin 《Journal of cellular and molecular medicine》2023,27(13):1900-1910
Endocrine disrupting chemicals have been known to contribute to the aggravation of inflammatory diseases including asthma. We aimed to investigate the effects of mono-n-butyl phthalate (MnBP) which is one of the representing phthalates, and its antagonist in an eosinophilic asthma mouse model. BALB/c mice were sensitized by intraperitoneal injection of ovalbumin (OVA) with alum and followed by three nebulized OVA challenges. MnBP was administered through drinking water administration throughout the study period, and its antagonist, apigenin, was orally treated for 14 days before OVA challenges. Mice were assessed for airway hyperresponsiveness (AHR), differential cell count and type 2 cytokines in bronchoalveolar lavage fluid were measured in vivo. The expression of the aryl hydrocarbon receptor was markedly increased when MnBP was administered. MnBP treatment increased AHR, airway inflammatory cells (including eosinophils), and type 2 cytokines following OVA challenge compared to vehicle-treated mice. However, apigenin treatment reduced all asthma features, such as AHR, airway inflammation, type 2 cytokines, and the expression of the aryl hydrocarbon receptor in MnBP-augmented eosinophilic asthma. Our study suggests that MnBP exposure may increase the risk of eosinophilic inflammation, and apigenin treatment may be a potential therapy for asthma exacerbated by endocrine-disrupting chemicals. 相似文献
815.
D Le Quoc K Le Quoc Y Gaudemer 《Comptes rendus des séances de la Société de biologie et de ses filiales》1977,171(4):935-941
Evidence for energy dependent variations of mitochondrial SH groups accessibility or reactivity was obtained using alkylating agents. These variations are thought to be consecutive to conformational changes affecting some proteins among them the phosphate carrier and the adenylic nucleotide translocator. 相似文献
816.
Dan Vanderpool Bui Quang Minh Robert Lanfear Daniel Hughes Shwetha Murali R. Alan Harris Muthuswamy Raveendran Donna M. Muzny Mark S. Hibbins Robert J. Williamson Richard A. Gibbs Kim C. Worley Jeffrey Rogers Matthew W. Hahn 《PLoS biology》2020,18(12)
Our understanding of the evolutionary history of primates is undergoing continual revision due to ongoing genome sequencing efforts. Bolstered by growing fossil evidence, these data have led to increased acceptance of once controversial hypotheses regarding phylogenetic relationships, hybridization and introgression, and the biogeographical history of primate groups. Among these findings is a pattern of recent introgression between species within all major primate groups examined to date, though little is known about introgression deeper in time. To address this and other phylogenetic questions, here, we present new reference genome assemblies for 3 Old World monkey (OWM) species: Colobus angolensis ssp. palliatus (the black and white colobus), Macaca nemestrina (southern pig-tailed macaque), and Mandrillus leucophaeus (the drill). We combine these data with 23 additional primate genomes to estimate both the species tree and individual gene trees using thousands of loci. While our species tree is largely consistent with previous phylogenetic hypotheses, the gene trees reveal high levels of genealogical discordance associated with multiple primate radiations. We use strongly asymmetric patterns of gene tree discordance around specific branches to identify multiple instances of introgression between ancestral primate lineages. In addition, we exploit recent fossil evidence to perform fossil-calibrated molecular dating analyses across the tree. Taken together, our genome-wide data help to resolve multiple contentious sets of relationships among primates, while also providing insight into the biological processes and technical artifacts that led to the disagreements in the first place.Combining three newly sequenced primate genomes with other published genomes, this study adapts a little-known method for detecting ancient introgression to genome-scale data, revealing multiple previously unknown examples of hybridization between primate species. 相似文献
817.
Quoc Ba Tran 《人类与生态风险评估》2020,26(6):1496-1511
AbstractCyanogenic glycosides (CGs) are commonly found in some edible plants and seeds. After ingestion, CGs can release toxic hydrogen cyanide (HCN) in humans. At present, unfortunately, there is no tool capable of predicting the cyanide concentration in human blood and organs following oral administration of CG-containing food. The aim of this study was to develop a physiologically based pharmacokinetic (PBPK) model of cyanide following the ingestion of CG-containing food in humans. To develop this model, pharmacokinetic data concerning cyanide concentration levels in humans exposed to potassium cyanide (KCN) and CG-containing foods (persipan paste, linseed, cassava, and bitter apricot kernels) were obtained from published data. This study created a model structure consisting of four organ compartments including the lungs, kidneys, liver, and slowly perfused tissues by employing Berkeley Madonna software to extract three unknown parameters including the maximum velocity of rhodanese, the absorption rate constant, and the bioavailability for oral administration of KCN and the four CG-containing foods (equivalent a 6.8?mg dose of cyanide). The model was then validated by comparing the simulated results for the concentration-time courses of cyanide levels in venous blood with data from two clinical studies covering the oral administration of KCN and linseed at three other doses. 相似文献
818.
Thi Thanh Thuy Hoang Loan Thi Cam Tu Nga Phi Le Quoc Phu Dao Phuong Hong Trinh 《Wetlands Ecology and Management》2012,20(5):399-408
Vietnamese coastal wetlands have traditionally been used for shrimp farming, but with the expansion of commercial shrimp farming and the associated clearance of mangroves, these valuable ecosystems have been rapidly degraded. The application of veterinary antibiotics in shrimp culture is one of the major threats to Vietnamese mangroves. These antibiotics are released into the environment through wastewater streams from shrimp ponds and cause environmental problems as well as the occurrence of antibiotic resistant bacteria. However, there is only a limited amount of information available on the occurrence and fate of antibiotics in Vietnamese mangroves. Ciprofloxacin and norfloxacin are two of most commonly fluoroquinolones used in shrimp culture. Laboratory experiments were therefore carried out using saline shrimp pond water to investigate the fate of both antibiotics in a coastal wetland ecosystem. Furthermore, two wetland plant species (Ceratophyllum demersum and Chrysopogon zizanioides), were used for studying phytoremediation of both antibiotics through a hydroponic experiment. Both ciprofloxacin and norfloxacin were photodegradable but at a slow rate, whereas the biodegradation seemed to be insignificant. If given at an initial concentration of 5 or 10?mg/L, a higher removal of antibiotics was achieved using C. demersum: 40?% for norfloxacin and 44?C39?% for ciprofloxacin, respectively. With C. zizanioides, ciprofloxacin and norfloxacin were reduced by 40?C38 and 36?C34?%, respectively. These results indicated that phytoremediation could be effective in the removal of both antibiotics. 相似文献
819.
820.
V. K. Nezdolii D. S. Pavlov Tran Thanh Lan Pham Hong Phuong Nguyen Quoc Khanh 《Journal of Ichthyology》2010,50(11):1002-1013
The first material is presented on downstream migration of fish juveniles in the Krasnaya River, one of the largest rivers
in South-East Asia. The spatial-temporal structure of distribution of downstream-migrating fish juveniles in the Krasnaya
River has traits usually characteristic of migration in rovers with turbid water. Concentration of fish was extremely variable
by the time of the day, river length, and depth. In length-wise distribution, there was a tendency to increasing concentration
of downstream migrants from the upper stretches to the downstream stretch. In the upper reaches, Perciformes prevailed, in
the middle part, Cypriniformes prevailed, and in the lower reaches of the river Clupeiformes prevailed. During 24 h, Clupeiformes
and Perciformes migrated more intensively at night and Cypriniformes migrated more in the daytime. By depth horizons, Clupeiformes
made downstream migration predominantly at the surface and Cypriniformes and Perciformes did at the bottom. These differences
may be caused by species differences in fish biology, local specific traits of stream hydraulics, anthropogenous factors,
etc. 相似文献