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121.
122.
Rapid loss of mosquito larvicidal potency ofBacillus
sphaericus (ISPC-6) during subculturing is correlated to the appearance of non toxic variants. Simultaneous loss of streptomycin resistance, urease and exoprotease is also observed in majority of the non toxic variants. The loss is however reversible because of the reappearance of toxic phenotype resembling wild type in the non toxic variants. 相似文献
123.
124.
C. L. Mahajan 《Journal of Zoology》1971,165(2):163-182
A detailed study of the head and pectoral musculature is reported. Many of the specializations and peculiarities can be correlated with the sluggish and bottom living habits of the fish. Muscles developed in connection with the movement of the maxillary and mandibular barbels and the strong pectoral spine are particularly noteworthy. No special muscles are found for the movement of the premaxillae. 相似文献
125.
Buffalo milk galactosyltransferase is a single poly-peptide of molecular weight 55,000 to 56,000. The enzyme is specific for
glucose as an acceptor substrate in the presence of 8-lactalbumin, L-Arabinose. L-xylose, D-ribose and D-fructose did not
serve as acceptor substrates even at concentration as high as 0.13 M, while N-acetylglucosamine and ovalbumin served as good
acceptors of galactosyl moiety in the absence of ∞ -lactalbumin. UDP-galacturonic acid did not serve as a donor substrate;
on the contrary, it inhibited the reaction. Lactose synthetase reaction was inhibited by D-ribose, L-arabinose and L-xylose,
whereas D-fructose did not show any inhibition. Buffalo milk ∞ -lactalbumin enhanced the synthesis of lactose but inhibited
the synthesis of N-acetyllactosamine. Cations like Ca2+, Mg2+, Cu2+, Ba2+ and Co2+ could not replace Mn2+ in the N-acetyllactosamine synthetase reaction. Except Co2+, these cations had no effect on this reaction. Co2+ was found to be a competitive inhibitor of Mn2+. The observed inhibition of the reaction by-EDTA also confirmed the absolute requirement of Mn2+ for the reaction. Lactose synthetase reaction had an optimum pH of 8.5, whereas N-acetyllactosamine synthetase reaction was
maximal at pH 8.0. 相似文献
126.
127.
128.
Patricia McGettigan Peter Roderick Rushikesh Mahajan Abhay Kadam Allyson M. Pollock 《PLoS medicine》2015,12(5)
Background
In 2012, an Indian parliamentary committee reported that manufacturing licenses for large numbers of fixed dose combination (FDC) drugs had been issued by state authorities without prior approval of the Central Drugs Standard Control Organization (CDSCO) in violation of rules, and considered that some ambiguity until 1 May 2002 about states’ powers might have contributed. To our knowledge, no systematic enquiry has been undertaken to determine if evidence existed to support these findings. We investigated CDSCO approvals for and availability of oral FDC drugs in four therapeutic areas: analgesia (non-steroidal anti-inflammatory drugs [NSAIDs]), diabetes (metformin), depression/anxiety (anti-depressants/benzodiazepines), and psychosis (anti-psychotics).Methods and Findings
This was an ecologic study with a time-trend analysis of FDC sales volumes (2007–2012) and a cross-sectional examination of 2011–2012 data to establish the numbers of formulations on the market with and without a record of CDSCO approval (“approved” and “unapproved”), their branded products, and sales volumes. Data from the CDSCO on approved FDC formulations were compared with sales data from PharmaTrac, a database of national drug sales. We determined the proportions of FDC sales volumes (2011–2012) arising from centrally approved and unapproved formulations and from formulations including drugs banned/restricted internationally. We also determined the proportions of centrally approved and unapproved formulations marketed before and after 1 May 2002, when amendments were made to the drug rules. FDC approvals in India, the United Kingdom (UK), and United States of America (US) were compared.For NSAID FDCs, 124 formulations were marketed, of which 34 (27%) were centrally approved and 90 (73%) were unapproved; metformin: 25 formulations, 20 (80%) approved, five (20%) unapproved; anti-depressants/benzodiazepines: 16 formulations, three (19%) approved, 13 (81%) unapproved; anti-psychotics: ten formulations, three (30%) approved, seven (70%) unapproved. After 1 May 2002, the proportions of approved FDC formulations increased for NSAIDs (26%/28%) and anti-psychotics (0%/38%) and decreased for metformin (100%/75%) and anti-depressants/benzodiazepines (20%/18%), and the overall proportion approved remained similar before and after that date.FDC formulations gave rise to multiple branded products, ranging from 211 anti-psychotic FDC products from ten formulations to 2,739 NSAID FDC products from 124 formulations. The proportions of FDC sales volumes arising from unapproved formulations were as follows: anti-depressants/benzodiazepines, 69%; anti-psychotics, 43%; NSAIDs, 28%; and metformin, 0.4%. Formulations including drugs banned/restricted internationally comprised over 12% of NSAID FDC sales and 53% of anti-psychotic FDC sales. Across the four therapeutic areas, 14 FDC formulations were approved in the UK and 22 in the US.Conclusions
There was evidence supporting concerns about FDCs. Metformin excepted, substantial numbers of centrally unapproved formulations for NSAID, anti-depressant/benzodiazepine, and anti-psychotic FDCs were marketed; sales volumes were high. The legal need for central approval of new drugs before manufacture has been in place continuously since 1961, including for FDCs meeting the applicable legal test. Proportions of centrally unapproved formulations after 1 May 2002 did not decrease overall, and no ambiguity was found about states’ licensing powers. Unapproved formulations should be banned immediately, prioritising those withdrawn/banned internationally and undertaking a review of benefits and risks for patients in ceasing or switching to other medicines. Drug laws need to be amended to ensure the safety and effectiveness of medicines marketed in India. 相似文献129.
Inamdar SR Savanur MA Eligar SM Chachadi VB Nagre NN Chen C Barclays M Ingle A Mahajan P Borges A Shastry P Kalraiya RD Swamy BM Rhodes JM Yu LG 《Glycobiology》2012,22(9):1227-1235
Glycan array analysis of Sclerotium rolfsii lectin (SRL) revealed its exquisite binding specificity to the oncofetal Thomsen-Friedenreich (Galβ1-3GalNAcα-O-Ser/Thr, T or TF) antigen and its derivatives. This study shows that SRL strongly inhibits the growth of human colon cancer HT29 and DLD-1 cells by binding to cell surface glycans and induction of apoptosis through both the caspase-8 and -9 mediated signaling. SRL showed no or very weak binding to normal human colon tissues but strong binding to cancerous and metastatic tissues. Intratumor injection of SRL at subtoxic concentrations in NOD-SCID mice bearing HT29 xenografts resulted in total tumor regression in 9 days and no subsequent tumor recurrence. As the increased expression of TF-associated glycans is commonly seen in human cancers, SRL has the potential to be developed as a therapeutic agent for cancer. 相似文献
130.
Mahajan DT Masand VH Patil KN Ben Hadda T Jawarkar RD Thakur SD Rastija V 《Bioorganic & medicinal chemistry letters》2012,22(14):4827-4835
In present work, 53 synthetic prodiginines were selected to establish thriving CoMSIA (Comparative Molecular Similarity Indices Analysis) model to explore the structural features influencing their anti-malarial activity. POM (Petra/Osiris/Molinspiration) was carried out to get insight into requirements that can lead to the improvement of the activity of these molecules. The CoMSIA model, based on a combination of steric, electrostatic and H-bond acceptor/donor effects, is with R(2)(cv)=0.738 and R(2)=0.911. The analyses reveal that lipophilicity, hydrogen donor/acceptor and steric factors play crucial role. The study with constructive propositions could be useful for the design of new analogues with enhanced activity. 相似文献