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61.
A bioprocess for machine washable wool, combining the advantages of both protease and transglutaminase in a simultaneous enzymatic treatment has been developed. This process reduced the felting tendency of woven wool fabrics by 9% at the expense of only 2% weight and tensile strength loss. In contrast to previously described protease-based processes for shrink resistant wool, the anti-felting properties achieved in the simultaneous enzymatic treatment produced insignificant fibre damage, confirmed also by scanning electron images of the fabrics. 相似文献
62.
Alastair D. MacKenzie Ross Martin G. Cook Heung Chong Mehnaz Hossain Hardev S. Pandha Dorothy C. Bennett 《Pigment cell & melanoma research》2013,26(2):226-235
The best‐established function of the melanoma‐suppressor p16 is mediation of cell senescence, a permanent arrest following cell proliferation or certain stresses. The importance of p16 in melanoma suggests indolence of the other major senescence pathway through p53. Little or no p53 is expressed in senescent normal human melanocytes, but p16‐deficient melanocytes can undergo p53‐mediated senescence. As p16 expression occurs in nevi but falls with progression toward melanoma, we here investigated whether p53‐dependent senescence occurs at some stage and, if not, what defects were detectable in this pathway, using immunohistochemistry. Phosphorylated checkpoint kinase 2 (CHEK2) can mediate DNA‐damage signaling, and under some conditions senescence, by phosphorylating and activating p53. Remarkably, we detected no prevalent p53‐mediated senescence in any of six classes of lesions. Two separate defects in p53 signaling appeared common: in nevi, lack of p53 phosphorylation by activated CHEK2, and in melanomas, defective p21 upregulation by p53 even when phosphorylated. 相似文献
63.
Huang QQ Hossain MM Wu K Parai K Pope RM Jin JP 《The Journal of biological chemistry》2008,283(38):25887-25899
The actin cytoskeleton plays a major role in cell motility that is essential for the function of phagocytes. Calponin is an actin-associated regulatory protein. Here we report the finding of significant levels of the h2 isoform of calponin in peripheral blood cells of myeloid lineage. To study the functional significance, h2-calponin gene (Cnn2) interrupted mice were constructed. Germ line transmission of the Cnn2-flox-neo allele was obtained in chimeras from two independent clones of targeted embryonic stem cells. The insertion of the neo(R) cassette into intron 2 of the Cnn2 gene resulted in a significant knockdown of h2-calponin expression. Removing the frt-flanked neo(R) cassette by FLP1 recombinase rescued the knockdown effect. Cre recombinase-induced deletion of the loxP-flanked exon 2 eliminated the expression of h2-calponin protein. H2-calponin-free mice showed reduced numbers of peripheral blood neutrophils and monocytes. H2-calponin-free macrophages demonstrated a higher rate of proliferation and faster migration than that of h2-calponin-positive cells, consistent with a faster diapedesis of peripheral monocytes and neutrophils. H2-calponin-free macrophages showed reduced spreading in adhesion culture together with decreased tropomyosin in the actin cytoskeleton. The lack of h2-calponin also significantly increased macrophage phagocytotic activity, suggesting a novel mechanism to regulate phagocyte functions. 相似文献
64.
65.
Golam Sarwar Raju Md Mizanur Rahman Moghal Mohammad Salim Hossain Md Mahadi Hassan Md Mustahsan Billah Sayed Koushik Ahamed SM Masud Rana 《Biological research》2014,47(1)
Background
The current study aims at evaluating the analgesic, anti-pyretic and anti-inflammatory properties of methanolic extract of the stem, bark and leaves of Launaea sarmentosa and Aegialitis rotundifolia roxb.Results
The AELS and AEAR extract presented a significant (***p < 0.001) dose dependent increase in reaction time in writhing method and showed inhibition of 63.1% and 57.1% respectively at the doses of 400 mg/kg body weight while standard drug showed (P < 0.001) inhibition of 69.23%. In tail immersion method, AELS and AEAR showed maximum time of tail retention at 30 min in hot water i.e. 6.93 sec and 6.54 sec respectively at highest doses of 400 mg/kg body weight than lower dose while standard pentazocine showed reaction time of 7.62 sec. The AELS and AEAR extract also exhibited promising anti-inflammatory effect as demonstrated by statistically significant inhibition of paw volume by 32.48% and 26.75% respectively at the dose of 400 mg/kg body weight while the value at the dose of 200 mg/kg body weight were linear to higher dose at the 3rd hour of study. On the other hand, Standard indomethacin inhibited 40.13% of inflammation (***P < 0.001). In Cotton-pellet granuloma method, AELS and AEAR extract at the dose of 400 mg/kg body weight exhibited inhibition of inflammation of 34.7% and 29.1% respectively while standard drug showed (P < 0.001) inhibition of 63.22%. Intraperitoneal administration of AELS and AEAR showed dose dependent decrease in body temperature in brewer’s yeast induced hyperthermia in rats at both doses. However, AELS significantly decreased body temperature (***p < 0.001) at 400 mg/kg compared to control.Conclusions
Present work propose that the methanolic extract of Launaea sarmentosa and Aegialitis rotundifolia roxb possesses dose dependent pharmacological action which supports its therapeutic use in folk medicine possibly mediated through the inhibition or blocking of release of prostaglandin and/or actions of vasoactive substances such as histamine, serotonin and kinins. 相似文献66.
Insaidoo FK Borbulevych OY Hossain M Santhanagopolan SM Baxter TK Baker BM 《The Journal of biological chemistry》2011,286(46):40163-40173
Modification of the primary anchor positions of antigenic peptides to improve binding to major histocompatibility complex (MHC) proteins is a commonly used strategy for engineering peptide-based vaccine candidates. However, such peptide modifications do not always improve antigenicity, complicating efforts to design effective vaccines for cancer and infectious disease. Here we investigated the MART-1(27-35) tumor antigen, for which anchor modification (replacement of the position two alanine with leucine) dramatically reduces or ablates antigenicity with a wide range of T cell clones despite significantly improving peptide binding to MHC. We found that anchor modification in the MART-1(27-35) antigen enhances the flexibility of both the peptide and the HLA-A*0201 molecule. Although the resulting entropic effects contribute to the improved binding of the peptide to MHC, they also negatively impact T cell receptor binding to the peptide·MHC complex. These results help explain how the "anchor-fixing" strategy fails to improve antigenicity in this case, and more generally, may be relevant for understanding the high specificity characteristic of the T cell repertoire. In addition to impacting vaccine design, modulation of peptide and MHC flexibility through changes to antigenic peptides may present an evolutionary strategy for the escape of pathogens from immune destruction. 相似文献
67.
Hashimoto M Hossain S Tanabe Y Shido O 《Prostaglandins, leukotrienes, and essential fatty acids》2005,73(6):475-483
Age-related changes in adenyl purine release from rat arteries and endothelial cell (EC) plasma membrane (PM) fluidity were studied. High performance liquid chromatography-fluorescence revealed that aging significantly decreased the release of adenyl purines. Pyrene-excimer spectroscopy disclosed that EC PM fluidity of aged rats decreased more significantly than that of young rats. An increase in cholesterol content and a decrease in the unsaturation index (USI) of fatty acids in cholesterol-enriched ECs reduced PM fluidity and 5'-nucleotidase (5'-ND) activity (measured by coupled assay of adenosine deaminase and glutamate dehydrogenase). Moreover, a decrease in cholesterol content and an increase in the USI of fatty acyl chains of the PM in docosahexaenoic acid-enriched ECs concurrently increased enzyme activity and extracellular adenosine. Therefore, decreases in PM fluidity, observed with age-dependent increased cholesterol and decreased USI, induce a decrease in 5'-ND activity, decrease extracellular adenosine levels, and might relate to hypertension in aged rats. 相似文献
68.
Rohini Bhat Anil Kumar Singh Muntazir Mushtaq Romesh Kumar Salgotra Manmohan Sharma Basharat Ahmad Bhat Umer Basu Ibrahim Al-Ashkar Mohammad Anwar Hossain Akihiro Ueda Ayman El Sabagh 《Phyton》2022,91(11):2439-2459
Identification of quantitative trait loci (QTLs) controlling yield and yield-related traits in rice was performed in
the F2 mapping population derived from parental rice genotypes DHMAS and K343. A total of 30 QTLs governing nine different traits were identified using the composite interval mapping (CIM) method. Four QTLs were
mapped for number of tillers per plant on chromosomes 1 (2 QTLs), 2 and 3; three QTLs for panicle number
per plant on chromosomes 1 (2 QTLs) and 3; four QTLs for plant height on chromosomes 2, 4, 5 and 6; one
QTL for spikelet density on chromosome 5; four QTLs for spikelet fertility percentage (SFP) on chromosomes
2, 3 and 5 (2 QTLs); two QTLs for grain length on chromosomes 1 and 8; three QTLs for grain width on chromosomes1, 3 and 8; three QTLs for 1000-grain weight (TGW) on chromosomes 1, 4 and 8 and six QTLs for yield
per plant (YPP) on chromosomes 2 (3 QTLs), 4, 6 and 8. Most of the QTLs were detected on chromosome 2, so
further studies on chromosome 2 could help unlock some new chapters of QTL for this cross of rice variety. Identified QTLs elucidating high phenotypic variance can be used for marker-assisted selection (MAS) breeding.
Further, the exploitation of information regarding molecular markers tightly linked to QTLs governing these traits
will facilitate future crop improvement strategies in rice. 相似文献
69.
Wagatsuma Tadao Tanaka Kazuhiro Iino Yuuichirou Satou Tsuyoshi Khan Md. Shahadat Hossain Tawaraya Keitaro 《Plant and Soil》2021,459(1-2):289-313
Plant and Soil - The major factors controlling the soil methane (CH4) concentration and CH4 emissions of various plant (mainly wetland) species were identified. Five plant species (Oryza sativa,... 相似文献
70.
Peptidomimetics are designed to overcome the poor pharmacokinetics and pharmacodynamics associated with the native peptide or protein on which they are based. The design of peptidomimetics starts from developing structure-activity relationships of the native ligand-target pair that identify the key residues that are responsible for the biological effect of the native peptide or protein. Then minimization of the structure and introduction of constraints are applied to create the core active site that can interact with the target with high affinity and selectivity. Developing peptidomimetics is not trivial and often challenging, particularly when peptides’ interaction mechanism with their target is complex. This review will discuss the challenges of developing peptidomimetics of therapeutically important insulin superfamily peptides, particularly those which have two chains (A and B) and three disulfide bonds and whose receptors are known, namely insulin, H2 relaxin, H3 relaxin, INSL3 and INSL5. 相似文献