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1.
Antiserum against an N-terminal sequence of murine prohormone convertase-1 (mPC1) incorporating the sequence immediatley following the junction between the putative pro-region and the active enzyme was obtained. This was accomplished using the multiple antigenic peptide (MAP) approach whereupon an 8-branched polylysine core to which are grafted multiple copies of a 16 amino acid peptide representing the N-terminal sequence of mPC1 (positions 84–99) was synthesized by solid-phase Fmoc chemistry. The ensuing peptide was purified and fully characterized by RP-HPLC, 1H-NMR, amino acid composition, peptide sequencing and ion-spray mass spectrometry. The immunological properties of the resulting antibodies in detecting recombinant PC1 in both crude and purified preparations were compared with antibodies raised against a similar N-terminal segment of PC1 but using the conventioanl method of peptide–carrier protein conjugation and also developed against a C-terminal fusion protein of PC1. Our data indicate that the MAP antibody was as efficient as both the amino and carboxy-terminal antibodies in qualitative as well as quantitative analysis of PC1 encoded protein by radioimmunoassay. Following an identical approach, antibodies against other prohormone convertases like furin, PC5/6 and PACE4 were also developed and subsequently applied to a number of biochemical and immunological studies. In each case, the ease of preparation and high immunogenicity of the MAP approach were confirmed and reside in the simplicity and rapidity with which a potent and useful antiserum is obtained.  相似文献   
2.
Metabolic changes during rooting in stem cuttings of five mangrove species   总被引:3,自引:0,他引:3  
Vegetative propagation through rooting in stem cuttings in five tree mangroves namely Bruguiera parviflora, Cynometra iripa, Excoecaria agallocha, Heritiera fomes, and Thespesia populnea using IAA, IBA and NAA was reported. Spectacular increase in the root number was noted in the cuttings of H. fomes and C. iripa treated together with IBA (5000 ppm) and NAA (2500 ppm). The highest number of roots was obtained with IBA (2500 ppm) and NAA (500 ppm) in E. agallocha. B. parviflora and T. populnea responded better to IAA and IBA treatment. The species specific variation in the rooting response to exogenous application of auxins was reflected in the metabolic changes during initiation and development of roots in cuttings. Biochemical analysis showed increase of reducing sugar in the above-girdled tissues at initiation as well as subsequent development of roots which was further enhanced by the use of auxins. Decreases in the total sugar, total carbohydrate and polyphenols and increase in total nitrogen were recorded in the girdled tissues and the high C/N ratio at the initial stage helped in initiation of roots in all the species. Interaction of IBA and NAA promoted starch hydrolysis better than IAA and IBA during root development and subsequently reduced the C/N ratio and increased the protein-nitrogen activity during root development which suggest the auxin influenced mobilization of nitrogen to the rooting zone.Abbreviations IAA Indole-3-acetic acid - IBA Indole-butyric acid - NAA A-naphthalene acetic acid  相似文献   
3.
Melovinone, a new alkaloid isolated from the roots of Melochia tomentosa has been characterized as 3,7,8-trimethoxy-2-methyl-5(5′-phenylpentyl)-4-quinolinone.  相似文献   
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Green synthesis of silver nanoparticles (AgNPs) has become a promising environmentally benign synthetic route in nanoscience and nanotechnology during recent years. In the present work, we have developed an environment-friendly and low-cost method for synthesis of silver nanoparticles from silver nitrate using aqueous fruit extract of Dillenia indica. The as-synthesized nanoparticles were characterized by UV-Vis spectrophotometer, transmission electron microscopy (TEM) and X-ray diffraction (XRD). FTIR study was performed to know the interaction of bio-molecules present in the fruit extract with AgNPs. The catalytic application of the as-synthesized AgNPs was demonstrated against degradation of methylene blue (MB) in aqueous system. The absorption spectra of colloidal suspension of AgNPs showed characteristic surface plasmon resonance (SPR) band centred at a wavelength of 416?nm. TEM image showed that the AgNPs were almost spherical in shape having an average diameter of 10.78?±?.48?nm. XRD pattern and selected area electron diffraction (SAED) pattern with bright spots signify the crystalline nature of nanoparticles. The fruit extract-capped AgNPs was highly stable and have showed the effective catalytic activity in reduction of MB dye.  相似文献   
6.
Atanu Sarkar 《EcoHealth》2010,7(1):114-126
Millions of people living in India are at risk by consuming arsenic contaminated groundwater. Several technological solutions have failed to address the problem due to segmental approaches, resulting in human suffering for a period of three decades. The article is based on an analysis of arsenic-related health problems from an ecosystem perspective through a primary survey conducted in five arsenic affected villages in the state of West Bengal and review of existing research and policy documents. Although modern agricultural practices and drinking water policies have resulted in arsenic contamination of groundwater, current mitigation policy is essentially confined to biomedical approaches, which includes potable water supply and medical care. The study also shows that existing disparity, difficulty in coping, inaccessibility to health service and potable water supply and lack of participation in decision making have resulted in more suffering among the poor. On the other hand, spreading of arsenic contamination in the ecosystem remains unabated. Foods grown in the affected area have emerged as additional sources of exposure to humans. There is lack of evidence of any perceivable benefits due to sustainable agriculture, as present nature of agriculture practice is essentially driven by crop yield only. Further research is needed to generate credible evidence of alternative agriculture paradigms that may eventually reduce body burden of arsenic through reduced dependency on groundwater.  相似文献   
7.
Breast Cancer (BCa) is the most often diagnosed cancer among women who were in the late 1940’s. Breast cancer growth is largely dependent on the expression of estrogen and progesterone receptor. Breast cancer cells may have one, both, or none of these receptors. The treatment for breast cancer may involve surgery, hormonal therapy (Tamoxifen, an aromatase inhibitor, etc.) and oral chemotherapeutic drugs. The molecular docking technique reported the findings on the potential binding modes of the 2‐(2‐bromo‐3‐nitrophenyl)‐5‐phenyl‐1,3,4‐oxadiazole derivatives with the estrogen receptor (PDB ID: 3ERT). The 1,3,4‐oxadiazole derivatives 4a – 4j have been synthesized and described by spectroscopic method. 2‐(2‐Bromo‐6‐nitrophenyl)‐5‐(4‐bromophenyl)‐1,3,4‐oxadiazole ( 4c ) was reconfirmed by single‐crystal XRD. All the compounds have been tested in combination with generic Imatinib pharmaceutical drug against breast cancer cell lines isolated from Caucasian woman MCF‐7, MDA‐MB‐453 and MCF‐10A non‐cancer cell lines. The compounds with the methoxy (in 4c ) and methyl (in 4j ) substitution were shown to have significant cytotoxicity, with 4c showing dose‐dependent activation and decreased cell viability. The mechanism of action was reported by induced apoptosis and tested by a DNA enzyme inhibitor experiment (ELISA) for Methyl Transferase. Molecular dynamics simulations were made for hit molecule 4c to study the stability and interaction of the protein?ligand complex. The toxicity properties of ADME were calculated for all the compounds. All these results provide essential information for further clinical trials.  相似文献   
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Statistics in Biosciences - Inference procedure is a critical step of experimental researches to draw scientific conclusions especially in multiple testing. The false positive rate increases unless...  相似文献   
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International Journal of Peptide Research and Therapeutics - The design for vaccines using in silico analysis of genomic data of different viruses has taken many different paths, but lack of any...  相似文献   
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