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71.
A search for the presence of mariner-like elements in the Labeo rohita genome by polymerase chain reaction led to the amplification of a partial DNA sequence coding for a putative transmembrane domain of gonadotropin hormone receptor. The amplified DNA sequence shows a high degree of homology to the available turkey and human luteinizing and follicle stimulating hormone receptor coding sequences. This is the first report on cloning such sequences of piscine origin. 相似文献
72.
Pandian RP Kutala VK Liaugminas A Parinandi NL Kuppusamy P 《Molecular and cellular biochemistry》2005,278(1-2):119-127
Oxygen consumption rate (OCR) and generation of superoxide and nitric oxide (NO) in mouse aortic endothelial cells (MAECs)
treated with lipopolysaccharide (LPS) were studied. The OCR was determined in cell suspensions at 37 °C by electron paramagnetic
resonance (EPR) spectroscopy. LPS significantly altered the OCR in a dose and time-dependent fashion. The OCR was significantly
elevated immediately following the treatment of MAECs with LPS (5 and 10 μg/ml) and NADPH (100 μM) whereas the same was depressed
1 h after exposure to similar conditions of incubation. Under similar experimental conditions, superoxide generation was also
determined by EPR spectroscopy and cytochrome c reduction assays. A marginal increase in the superoxide production was observed when the cells were treated with LPS and
NADPH alone whereas the same was further enhanced significantly when the cells were treated with LPS and NADPH together. The
increase in oxygen consumption and superoxide production caused by LPS was inhibited by diphenyleneiodonium (DPI), suggesting
the involvement of NAD(P)H oxidase. A significant increase in the NO production by MAECs was noticed 1 h after treatment with
LPS and was inhibited by L-NAME, further suggesting the involvement of nitric oxide synthase (NOS). Thus, on a temporal scale,
LPS-induced alterations in oxygen consumption by MAECs may be under the control of dual regulation by NAD(P)H oxidase and
NOS. (Mol Cell Biochem 278: 119–127, 2005) 相似文献
73.
Proliferating cell nuclear antigen (PCNA) as a proliferative marker during embryonic and adult zebrafish hematopoiesis 总被引:4,自引:1,他引:3
Leung AY Leung JC Chan LY Ma ES Kwan TT Lai KN Meng A Liang R 《Histochemistry and cell biology》2005,124(2):105-111
We investigated the expression of proliferative cell nuclear antigen (PCNA) in zebrafish to delineate the proliferative hematopoietic
component during adult and embryonic hematopoiesis. Immunostaining for PCNA and enhanced green fluorescence protein (eGFP)
was performed in wild-type and fli1-eGFP (endothelial marker) and gata1-eGFP (erythroid cell marker) transgenic fish. Expression
of PCNA mRNA was examined in wild-type and chordin morphant embryos. In adult zebrafish kidney, the renal tubules are surrounded
by endothelial cells and it is separated into hematopoietic and excretory compartments. PCNA was expressed in hematopoietic
progenitor cells but not in mature neutrophils, eosinophils or erythroid cells. Some PCNA+ cells are scattered in the hematopoietic
compartment of the kidney while others are closely associated with renal tubular cells. PCNA was also expressed in spermatogonial
stem cells and intestine crypts, consistent with its role in cell proliferation and DNA synthesis. In embryos, PCNA is expressed
in the brain, spinal cord and intermediate cell mass (ICM) at 24 h-post fertilization. In chordin morphants, PCNA is significantly
upregulated in the expanded ICM. Therefore, PCNA can be used to mark cell proliferation in zebrafish hematopoietic tissues
and to identify a population of progenitor cells whose significance would have to be further investigated. 相似文献
74.
Cloning, sequencing and expression of cDNA encoding growth hormone from Indian catfish (Heteropneustes fossilis) 总被引:2,自引:0,他引:2
A tissue-specific cDNA library was constructed using polyA+ RNA from pituitary glands of the Indian catfishHeteropneustes fossilis (Bloch) and a cDNA clone encoding growth hormone (GH) was isolated. Using polymerase chain reaction (PCR) primers representing
the conserved regions of fish GH sequences the 3′ region of catfish GH cDNA (540 bp) was cloned by random amplification of
cDNA ends and the clone was used as a probe to isolate recombinant phages carrying the full-length cDNA sequence. The full-length
cDNA clone is 1132 bp in length, coding for an open reading frame (ORF) of 603 bp; the reading frame encodes a putative polypeptide
of 200 amino acids including the signal sequence of 22 amino acids. The 5′ and 3′ untranslated regions of the cDNA are 58
bp and 456 bp long, respectively. The predicted amino acid sequence ofH. fossils GH shared 98% homology with other catfishes. Mature GH protein was efficiently expressed in bacterial and zebrafish systems
using appropriate expression vectors. The successful expression of the cloned GH cDNA of catfish confirms the functional viability
of the clone. 相似文献
75.
T. J. Pandian 《Helgoland Marine Research》1980,33(1-4):415-421
Dam-building across naturally flowing rivers tends to decrease discharge of surplus water into the sea, reduce nutrient concentration
in estuaries and coastal waters, and diminish plankton blooms as well as fish landings. Depletion of nutrients and organic
matter along with reduced mud and silt deposition affect benthic life on the continental shelf. Reduced mud and silt deposition
leads to coastal retreat. Dams, especially those constructed for hydro-electric purposes, hinder migration of fishes and decapods.
Discharge from dams can create barriers at high or low flows, cause delays, disrupt normal behavioural routine and change
the travel speed of migratory animals. Where all spawners of a given population are frequently kept away from the breeding
site, the population faces extinction. 相似文献
76.
Over the past few years, secure and privacy-preserving user authentication scheme has become an integral part of the applications of the healthcare systems. Recently, Wen has designed an improved user authentication system over the Lee et al.’s scheme for integrated electronic patient record (EPR) information system, which has been analyzed in this study. We have found that Wen’s scheme still has the following inefficiencies: (1) the correctness of identity and password are not verified during the login and password change phases; (2) it is vulnerable to impersonation attack and privileged-insider attack; (3) it is designed without the revocation of lost/stolen smart card; (4) the explicit key confirmation and the no key control properties are absent, and (5) user cannot update his/her password without the help of server and secure channel. Then we aimed to propose an enhanced two-factor user authentication system based on the intractable assumption of the quadratic residue problem (QRP) in the multiplicative group. Our scheme bears more securities and functionalities than other schemes found in the literature. 相似文献
77.
78.
Background
Bacterial community composition in the marine environment differs from one geographical location to another. Reports that delineate the bacterial diversity of different marine samples from geographically similar location are limited. The present study aims to understand whether the bacterial community compositions from different marine samples harbour similar bacterial diversity since these are geographically related to each other.Methods and Principal Findings
In the present study, 16S rRNA deep sequencing analysis targeting V3 region was performed using Illumina bar coded sequencing. A total of 22.44 million paired end reads were obtained from the metagenomic DNA of Marine sediment, Rhizosphere sediment, Seawater and the epibacterial DNA of Seaweed and Seagrass. Diversity index analysis revealed that Marine sediment has the highest bacterial diversity and the least bacterial diversity was observed in Rhizosphere sediment. Proteobacteria, Actinobacteria and Bacteroidetes were the dominant taxa present in all the marine samples. Nearly 62–71% of rare species were identified in all the samples and most of these rare species were unique to a particular sample. Further taxonomic assignment at the phylum and genus level revealed that the bacterial community compositions differ among the samples.Conclusion
This is the first report that supports the fact that, bacterial community composition is specific for specific samples irrespective of its similar geographical location. Existence of specific bacterial community for each sample may drive overall difference in bacterial structural composition of each sample. Further studies like whole metagenomic sequencing will throw more insights to the key stone players and its interconnecting metabolic pathways. In addition, this is one of the very few reports that depicts the unexplored bacterial diversity of marine samples (Marine sediment, Rhizosphere sediment, Seawater) and the host associated marine samples (Seaweed and Seagrass) at higher depths from uncharacterised coastal region of Palk Bay, India using next generation sequencing technology. 相似文献79.
The marine environment is a virtually untapped source of novel actinomycete diversity and its metabolites. Investigating the diversity of actinomycetes in other marine macroorganisms, like seaweeds and sponges, have resulted in isolation of novel bioactive metabolites. Actinomycetes diversity associated with corals and their produced metabolites have not yet been explored. Hence, in this study we attempted to characterize the culturable actinomycetes population associated with the coral Acropora digitifera. Actinomycetes were isolated from the mucus of the coral wherein the actinomycetes count was much higher when compared with the surrounding seawater and sediment. Actinobacteria-specific 16S rRNA gene primers were used for identifying the isolates at the molecular level in addition to biochemical tests. Amplified ribosomal DNA restriction analysis using three restriction enzymes revealed several polymorphic groups within the isolates. Sequencing and blast analysis of the isolates revealed that some isolates had only 96.7% similarity with its nearest match in GenBank indicating that they may be novel isolates at the species level. The isolated actinomycetes exhibited good antibacterial activity against various human pathogens. This study offers for the first time a prelude about the unexplored culturable actinomycetes diversity associated with a scleractinian coral and their bioactive capabilities. 相似文献
80.
Suresh Kumar R Ashraf Ali M Osman H Ismail R Choon TS Yoon YK Wei AC Pandian S Manogaran E 《Bioorganic & medicinal chemistry letters》2011,21(13):3997-4000
Hexacyclic derivatives share vital pharmacological properties, considered useful in Alzheimer’s disease. The aim of this study was synthesis and its evaluation for acetyl cholinesterase inhibitory activity of novel hexacyclic analogues. Compound 4f, showed potent inhibitory activity against acetyl cholinesterase enzyme with IC50 0.72 μmol/L. 相似文献