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1.
A complete cellulase from Penicillium pinophilum was evaluated for the hydrolysis of α-cellulose derived from steam exploded sugarcane bagasse and other cellulosic substrates. α-Cellulose at 1% substrate concentration was completely hydrolyzed by Penicillium cellulase within 3 h wherein at 10% the hydrolysis was 100% within 24 h with an enzyme loading of 10 FPU/g. The hydrolysate yielded glucose as major end product as analyzed by HPLC. Under similar conditions, hydrolysis of Sigmacell (microcrystalline cellulose), CP-123 (pulverized cellulose powder) and ball milled Solka Floc were 42%, 56% and 52%, respectively. Further the hydrolysis performance of Penicillium sp. cellulase is compared with Trichoderma reesei cellulase (AccelleraseTM 1000) from Genencore. The kinetics of hydrolysis with respect to enzyme and substrate concentration will be presented. 相似文献
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Minehira K Young SG Villanueva CJ Yetukuri L Oresic M Hellerstein MK Farese RV Horton JD Preitner F Thorens B Tappy L 《Journal of lipid research》2008,49(9):2038-2044
The liver secretes triglyceride-rich VLDLs, and the triglycerides in these particles are taken up by peripheral tissues, mainly heart, skeletal muscle, and adipose tissue. Blocking hepatic VLDL secretion interferes with the delivery of liver-derived triglycerides to peripheral tissues and results in an accumulation of triglycerides in the liver. However, it is unclear how interfering with hepatic triglyceride secretion affects adiposity, muscle triglyceride stores, and insulin sensitivity. To explore these issues, we examined mice that cannot secrete VLDL [due to the absence of microsomal triglyceride transfer protein (Mttp) in the liver]. These mice exhibit markedly reduced levels of apolipoprotein B-100 in the plasma, along with reduced levels of triglycerides in the plasma. Despite the low plasma triglyceride levels, triglyceride levels in skeletal muscle were unaffected. Adiposity and adipose tissue triglyceride synthesis rates were also normal, and body weight curves were unaffected. Even though the blockade of VLDL secretion caused hepatic steatosis accompanied by increased ceramides and diacylglycerols in the liver, the mice exhibited normal glucose tolerance and were sensitive to insulin at the whole-body level, as judged by hyperinsulinemic euglycemic clamp studies. Normal hepatic glucose production and insulin signaling were also maintained in the fatty liver induced by Mttp deletion. Thus, blocking VLDL secretion causes hepatic steatosis without insulin resistance, and there is little effect on muscle triglyceride stores or adiposity. 相似文献
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PknH, a transmembrane Hank's type serine/threonine kinase from Mycobacterium tuberculosis is differentially expressed under stress conditions 总被引:1,自引:0,他引:1
Sharma K Chandra H Gupta PK Pathak M Narayan A Meena LS D'Souza RC Chopra P Ramachandran S Singh Y 《FEMS microbiology letters》2004,238(1):107-113
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Cytomegalovirus seropositivity drives the CD8 T cell repertoire toward greater clonality in healthy elderly individuals 总被引:24,自引:0,他引:24
Khan N Shariff N Cobbold M Bruton R Ainsworth JA Sinclair AJ Nayak L Moss PA 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(4):1984-1992
The deterioration in immune function with aging is thought to make a major contribution to the increased morbidity and mortality from infectious disease in old age. One aspect of immune senescence is the reduction in CD8 T cell repertoire as due to the accumulation of oligoclonal, memory T cells and a reduction in the naive T cell pool. CD8 T cell clonal expansions accumulate with age, but their antigenic specificity remains unknown. In this study, we show that in elderly individuals seropositivity for human CMV leads to the development of oligoclonal populations of CMV-specific CTL that can constitute up to one-quarter of the total CD8 T cell population. Furthermore, CMV-specific CTL have a highly polarized membrane phenotype that is typical of effector memory cells (CD28(-), CD57(+), CCR7(-)). TCR analyses show that CMV-specific CTL have highly restricted clonality with greater restriction in the larger expansions. Clonal analysis of the total CD8 T cell repertoire was compared between CMV-seropositive and CMV-seronegative donors. Thirty-three percent more clonal expansions were observed in CMV-seropositive donors in comparison with seronegative individuals. These data implicate CMV as a major factor in driving oligoclonal expansions in old age. Such a dramatic accumulation of virus-specific effector CTL might impair the ability to respond to heterologous infection and may underlie the negative influence of CMV seropositivity on survival in the very elderly. 相似文献
6.
Sharma VM Prasanna P Seshu KV Renuka B Rao CV Kumar GS Narasimhulu CP Babu PA Puranik RC Subramanyam D Venkateswarlu A Rajagopal S Kumar KB Rao CS Mamidi NV Deevi DS Ajaykumar R Rajagopalan R 《Bioorganic & medicinal chemistry letters》2002,12(17):2303-2307
In our endeavor to design and synthesize novel anticancer agents, a new series of indoloquinazoline compounds were prepared and tested initially for anticancer activity in vitro against a panel of human cancer cell lines. Most of these compounds exhibited cytotoxic activity in in vitro screens. Compounds were selected and further evaluated using a modified Hollow Fiber Assay for their preliminary in vivo activity against 12 cell lines implanted in the subcutaneous and intraperitoneal compartments in mice. The results indicate that these compounds may constitute a new class of anticancer agents. 相似文献
7.
Sudesh Raj Sharma Smith Giri Utsav Timalsina Sanjiv Sudarshan Bhandari Bikash Basyal Kusum Wagle Laxman Shrestha 《PloS one》2015,10(4)
Birth weight of a child is an important indicator of its vulnerability for childhood illness and chances of survival. A large number of infant deaths can be averted by appropriate management of low birth weight babies and prevention of factors associated with low birth weight. The prevalence of low birth weight babies in Nepal is estimated to be about 12-32%.Our study aimed at identifying major determinants of low birth weight among term babies in Nepal. A hospital-based retrospective case control study was conducted in maternity ward of Tribhuvan University Teaching Hospital from February to July 2011. A total of 155 LBW babies and 310 controls were included in the study. Mothers admitted to maternity ward during the study period were interviewed, medical records were assessed and anthropometric measurements were done. Risk factors, broadly classified into proximal and distal factors, were assessed for any association with birth of low-birth weight babies. Regression analysis revealed that a history of premature delivery (adjusted odds ratio; aOR5.24, CI 1.05-26.28), hard physical work during pregnancy (aOR1.48, CI 0.97-2.26), younger age of mother (aOR1.98, CI 1.15-3.41), mothers with haemoglobin level less than 11gm/dl (aOR0.51, CI0.24-1.07) and lack of consumption of nutritious food during pregnancy (aOR1.99, CI 1.28-3.10) were significantly associated with the birth of LBW babies. These factors should be addressed with appropriate measures so as to decrease the prevalence of low birth weight among term babies in Nepal. 相似文献
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One hundred and forty two cotton germplasm lines were screened for cotton leaf curl virus symptoms in field evaluations during 2003, 2004, and 2005. Fifty cross combinations involving 30 of these lines classified resistant or susceptible were used for inheritance study of the disease. All the F(1) plants of crosses involving resistant x resistant, resistant x susceptible, and susceptible x resistant parents were resistant, indicating dominant expression of the disease resistance and there were no maternal or cytoplasmic effects detected from reciprocal hybridization. In 22 crosses, 4 types of segregation patterns were obtained in the F(2) generations. A good fit for 15 (resistant):1 (susceptible), 13 (resistant):3 (susceptible), 9 (resistant):7 (susceptible) ratios indicated digenic control of the trait with duplicate dominant, dominant inhibitory, and duplicate recessive epistasis, respectively. Three-gene control with triplicate dominant epistasis was obtained in one of the crosses. This segregation pattern, however, needs further confirmation due to smaller population size. The absence of complementary gene action was obtained in 1 susceptible x susceptible and 27 resistant x resistant crosses as their F(1)s were susceptible and resistant, respectively, and F(2) generation lacked segregation. 相似文献
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Nirogi RV Deshpande AD Kambhampati R Badange RK Kota L Daulatabad AV Shinde AK Ahmad I Kandikere V Jayarajan P Dubey PK 《Bioorganic & medicinal chemistry letters》2011,21(1):346-349
N1-Arylsulfonyl-3-piperazinyl indole derivatives were designed and identified as a novel class of 5-HT6 receptors ligands. All the compounds have high affinity and antagonist activity towards 5-HT6 receptor. The compound 7a (Ki = 3.4 nM, functional assay IC50 = 310 nM) shows enhanced cognitive effect when tested in NORT and Morris water maze models. Synthesis, SAR and PK profile of these novel compounds constitute the subject matter of this Letter. 相似文献
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Herpesvirus-specific CD8 T cell immunity in old age: cytomegalovirus impairs the response to a coresident EBV infection 总被引:9,自引:0,他引:9
Khan N Hislop A Gudgeon N Cobbold M Khanna R Nayak L Rickinson AB Moss PA 《Journal of immunology (Baltimore, Md. : 1950)》2004,173(12):7481-7489
Aging in humans is associated with increased infections and the reduced proliferative capacity of T cells, part of the more global phenomenon termed immune senescence. The etiology of immune senescence is unknown but the accumulation of virus-specific memory T cells may be a contributory factor. We have examined CD8 T cell responses to two persistent herpesvirus infections, CMV and EBV, and to a recurrent virus infection, influenza, in different age cohorts of healthy donors using HLA-peptide tetramers and intracellular cytokine detection. Of these, CMV appears to be the most immunogenic, with the CD8 T cell response representing over 10% of the CD8 pool in many elderly donors. Interestingly, the effect of age upon EBV-specific responses depends upon donor CMV sero-status. In CMV seropositive donors, the magnitude of the EBV-specific immune response is stable with age, but in CMV seronegative donors, the response to EBV increases significantly with age. By contrast, the influenza-specific CD8 T cell immune response decreases with age, independent of CMV status. The functional activity of the herpesvirus-specific immune response decreases in elderly donors, although the characteristic phenotypes of CMV- and EBV-specific memory populations are retained. This demonstrates that aging is associated with a marked accumulation of CMV-specific CD8 T cells together with a decrease in immediate effector function. Moreover, infection with CMV can reduce prevailing levels of immunity to EBV, another persistent virus. These results suggest that carriage of CMV may be detrimental to the immunocompetent host by suppressing heterologous virus-specific immunity during aging. 相似文献