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71.
Mohammed Wasim Siddiqui Moasosang Longkumer Md. Shamsher Ahmad Kalyan Barman Pran Krishna Thakur Jahangir Kabir 《Acta Physiologiae Plantarum》2014,36(12):3115-3122
Sapota is cultivated in many countries of tropical and subtropical climate. It is delicious, nutritive, and commercially grown mainly for fresh consumption. Postharvest life of sapota is very short due to its highly perishable nature and other many reasons such as quick ripening, faster senescence, rapid loss of moisture, microbial spoilage, and fruit sensitivity to cold storage. To maintain and/or increase the shelf life of sapota, proper postharvest management is required. Unfortunately, very little work has been done so far, with limited success, leaving scarce literature published on postharvest management technologies of sapota. Different pre and postharvest treatments to reduce metabolic activity and quality loss have been suggested. Moreover, proper storage temperature and packaging may be used to increase the shelf life of fruits. This review explores the postharvest technologies adopted to enhance the shelf life of sapota during storage and distribution channel. 相似文献
72.
Pan X Hussain FN Iqbal J Feuerman MH Hussain MM 《The Journal of biological chemistry》2007,282(23):17078-17089
Carbon tetrachloride (CCl(4)) interferes with triglyceride secretion and causes steatosis, fibrosis, and necrosis. In mice, CCl(4) decreased plasma triglyceride-rich lipoproteins, increased cellular lipids, and reduced microsomal triglyceride transfer protein (MTP) without diminishing mRNA levels. Similarly, CCl(4) decreased apoB-lipoprotein production and MTP activity but had no effect on mRNA levels in primary enterocytes and colon carcinoma and hepatoma cells. CCl(4) did not affect MTP synthesis but induced post-translational degradation involving ubiquitinylation and proteasomes in McA-RH7777 cells. By contrast, MTP inhibitor increased cellular lipids without affecting MTP protein. MTP was covalently modified when cells were incubated with (14)CCl(4). This modification was prevented by the inhibition of P450 oxygenases, indicating that CCl(3)(.) generated by these enzymes targets MTP for degradation. To determine whether inhibition of proteolysis could prevent CCl(4) toxicity, mice were fed with CCl(4) with or without lactacystin. Lactacystin increased ubiquitinylated MTP and prevented lipid accumulation in tissues. Thus, CCl(4) induces post-translational degradation without affecting lipid transfer activity, whereas MTP antagonist inhibits lipid transfer activity without causing its destruction. These studies identify MTP as a major target of CCl(4) and its degradation as a novel mechanism involved in the onset of steatosis, suggesting that inhibition of proteolysis may prevent some forms of steatosis. 相似文献
73.
Antje Bodensieck Walter M.F. Fabian Olaf Kunert Ferdinand Belaj Sajid Jahangir Wolfgang Schühly Rudolf Bauer 《Chirality》2010,22(3):308-319
In‐depth conformational analyses of 10 known eremophilane (= (1S,4aR,7R,8aR)‐decahydro‐1,8a‐dimethyl‐7‐(1‐methylethyl)napththalene) sesquiterpenes, 1 – 10 , from Petasites hybridus were performed with molecular mechanics as well as density functional theory methods. Electronic transition energies and rotational strengths of these eight eremophilane lactones and two petasins were calculated by time‐dependent density functional theory (B3PW91/TZVP). The absolute configurations of the constituents could be assigned by comparison of their simulated and experimental circular dichroism (CD) spectra in methanol as (4S,5R,8S,10R) ( 1 , 2 ), (2R,4S,5R,8S,10R) ( 3 , 4 , 5 ), (2R,4S,5R,8R,9R,10R) ( 6 ), (2R,4S,5R,8R,10R) ( 7 , 8 ), and (3R,4R,5R) ( 9 , 10 ). Single‐crystal X‐ray diffraction data of 8β‐hydroxyeremophilanolide ((8S)‐8‐hydroxyeremophil‐7(11)‐en‐12,8‐olide) ( 1 ) served as starting point for the theoretical conformational calculations of the 8β‐epimers of the eremophilane lactones. Experimental CD spectra as well as 1H NMR spectra of compound 1 in methanol were considerably dependent on sample concentration. Chirality, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
74.
75.
Nazmun Nahar Rebeca Sultana Emily S. Gurley M. Jahangir Hossain Stephen P. Luby 《EcoHealth》2010,7(2):196-203
Nipah virus (NiV) infection is a seasonal disease in Bangladesh that coincides with the date palm sap collection season. Raw
date palm sap is a delicacy to drink in Bengali culture. If fruit bats that are infected with NiV gain access to the sap for
drinking, they might occasionally contaminate the sap through saliva and urine. In February 2007, we conducted a qualitative
study in six villages, interviewing 27 date palm sap collectors (gachhis) within the geographical area where NiV outbreaks have occurred since 2001. Gachhis reported that bats pose a challenge to successful collection of quality sap, because bats drink and defecate into the sap
which markedly reduces its value. They know some methods to prevent access by bats and other pests but do not use them consistently,
because of lack of time and resources. Further studies to explore the effectiveness of these methods and to motivate gachhis to invest their time and money to use them could reduce the risk of human Nipah infection in Bangladesh. 相似文献
76.
The structure of postsynaptic densities isolated from dog cerebral cortex: II. characterization and arrangement of some of the major proteins within the structure 总被引:15,自引:0,他引:15 下载免费PDF全文
An attempt was made to identify some of the proteins of the postsynaptic density (PSD) fraction isolated from dog cerebral cortex. The major protein has been tentatively labeled "neurofilament" protein, on the basis of its 51,000 mol wt correspondence to a protein found in neurofilament preparations. Other proteins are akin to some dog myofibrillar proteins, on the basis if immunological crossreaction and equal sodium dodecyl sulfate (SDS)-gel electrophoretic mobilities. While a protein similar to dog muscle myosin is not present in the PSD fraction, a major protein present is actin, as evident from reactivity with antiactin serum, from SDS-gel mobility, and from amino acid composition. Only very little tubulin may be present in the PSD fraction, as determined by gel electrophoresis. Various treatments of the PSD fraction were attempted in order to extract some proteins, as revealed by gel electrophoresis, and to observe the structural changes of the PSD fraction residue after extraction of these proteins. The PSD is remarkably resistant to various extraction conditions, with only 4 M guanidine being found to extract most of the proteins, except the 51,000 mol wt protein. Disulfide reducing agents such as dithiothreitol (DTT), blocking agents such as p-chloromercuribenzoate (PCMB) (both in the presence of deoxycholate [DOC]), a Ca++ extractor, ethylene glycol-bis (beta- aminoethyl ether) N,N,N',N'-tetraacetate (EGTA), and guanidine caused an opening up of the native dense PSD structure, revealing approximately 10-nm filaments, presumably consisting of "neurofilament" protein. Both DTT-DOC and PCMB-DOC removed chiefly actin but also some other proteins. EGTA, in greatly opening up the structure, as observed in the electron microscope, revealed both 10-nm and 3- to 5-nm filaments; the later could be composed of actin, since actin was still in the residue after the treatment. EGTA removed a major 18,000 mol wt component and two minor proteins of 68,000 and 73,000 mol wt. Based on the morphological and biochemical evidence, a picture is presented of the PSD as a structure partly made up of 10-nm and 3- to 5-nm filaments, held together through Ca++ interaction and by bonds amendable to breakage by sulfhydrylblocking and disulfide-reducing reagents; either removal of Ca++ and/or rupture of these disulfide bonds opens up the structure. On the basis of the existence of filamentous proteins and the appearance of the PSD after certain treatments as a closed or open structure, a theory is presented with envisages the PSD to function as a modulator in the conduction of the nerve impulse, by movements of its protein relative. 相似文献
77.
78.
Mujeebur Rahman Khan M.Wajid Khan M.Jahangir Pasha 《Environmental and Experimental Botany》1998,40(3):265-273
Environment is a major factor that does influence host parasite relationships. Air pollution caused by SO2 may directly alter the environment around the plant and pathogen. It is hypothesised that plants may respond differently to foliar pathogens in air polluted environments. To test this hypothesis, effects of intermittent exposures of SO2 at 143, 286 and 571 μg m−3 were investigated on the development of powdery mildew of cucumber (Cucumis sativa) caused by Sphaerotheca fuliginea, using pre-, post- and concomitant-inoculation exposures in closed-top chambers. Sulfur dioxide (except 143 μg m−3) and the fungus acting alone caused chlorosis and/or necrosis, and mildew colonies on leaves, respectively and both reduced the plant growth and yield of cucumber. Fungus colonization was relatively greater on the plants exposed to 143 μg SO2 m−3, but at the higher concentrations, the colonies were greatly suppressed. Gas injury on fungus-infected plants was also less in the other treatments. Conidia of S. fuliginea collected from exposed plants varied in size. Conidial germination was considerably greater at 143 μg SO2 m−3. This concentration also promoted germination of the conidia exposed on glass slides. Higher concentrations (286 and 571 μg m−3), however, suppressed the germination of conidia from exposed plants or exposed on glass slides. The number of fibrosin bodies declined at all the concentrations. Synergistic effects of 143 μg SO2 m−3 and S. fuliginea were recorded on plant growth and yield of cucumber. Sulfur dioxide at 571 μg m−3 and powdery mildew infection had an antagonistic effect on plant growth. 相似文献
79.
Steven Van Pottelberge Jahangir Khajehali Thomas Van Leeuwen Luc Tirry 《Experimental & applied acarology》2009,47(4):301-309
In this study the reproductive capacity of a laboratory-selected spirodiclofen resistant strain was investigated after treatment
with spirodiclofen. Firstly, females were exposed to different concentrations of spirodiclofen (200 and 1,000 mg/l) during
6, 12 or 24 h. In contrast to the susceptible parental strain, the fecundity and fertility of resistant mites was not affected
by treatment with these concentrations after any time of exposure tested. Secondly, pre-treatment of the resistant females
with the synergists PBO or DEF could increase the inhibitory effect of spirodiclofen on reproduction, demonstrating the possible
involvement of monooxygenases and esterases in metabolic detoxification of the acaricide. Because spirodiclofen interferes
with lipid biosynthesis, total lipid content was measured in female adults. There were no significant differences between
treated and non-treated female adults, both in the susceptible and resistant strain. However, the total lipid content in the
resistant females was significantly higher than in susceptible females. Our data shows that the detection of spirodiclofen
resistance should not be limited to mortality bioassays with eggs or larvae, but should be combined with inhibitory studies
on female fertility and fecundity. 相似文献
80.
Jahangir Iqbal Xiaosong Li Benny Hung-Junn Chang Lawrence Chan Gary J. Schwartz Streamson C. Chua Jr. M. Mahmood Hussain 《Journal of lipid research》2010,51(7):1929-1942
Fat is delivered to tissues by apoB-containing lipoproteins synthesized in the liver and intestine with the help of an intracellular chaperone, microsomal triglyceride transfer protein (MTP). Leptin, a hormone secreted by adipose tissue, acts in the brain and on peripheral tissues to regulate fat storage and metabolism. Our aim was to identify the role of leptin signaling in MTP regulation and lipid absorption using several mouse models deficient in leptin receptor (LEPR) signaling and downstream effectors. Mice with spontaneous LEPR B mutations or targeted ablation of LEPR B in proopiomelanocortin (POMC) or agouti gene related peptide (AGRP) expressing cells had increased triglyceride in plasma, liver, and intestine. Furthermore, melanocortin 4 receptor (MC4R) knockout mice expressed a similar triglyceride phenotype, suggesting that leptin might regulate intestinal MTP expression through the melanocortin pathway. Mechanistic studies revealed that the accumulation of triglyceride in the intestine might be secondary to decreased expression of MTP and lipid absorption in these mice. Surgical and chemical blockade of vagal efferent outflow to the intestine in wild-type mice failed to alter the triglyceride phenotype, demonstrating that central neural control mechanisms were likely not involved in the observed regulation of intestinal MTP. Instead, we found that enterocytes express LEPR, POMC, AGRP, and MC4R. We propose that a peripheral, local gut signaling mechanism involving LEPR B and MC4R regulates intestinal MTP and controls intestinal lipid absorption. 相似文献