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31.
32.
Saroj Sanan Geeta Sharma Rakesh Malhotra Devindar P. Sanan Parveen Jain Prem Vadhera 《Free radical research》1989,6(1):29-38
Haemorrhagic shock was produced in anaesthetized dogs, by rapid arterial bleeding to mean arterial blood pressure 35 mmHg, and maintained oligaemic for 4 h followed by return of withdrawn blood(R0WB). Dogs were observed for 72 h after ROWB for survival and recovery, and, for histopathological (HP) studies on liver, dogs were sacrificed 2 h after ROWB in non-survival experiments. Desferrioxamine mesylate (25mg/kg) was administered intra-muscularly at 2,3 and 4h after blood loss in survival experiments and for HP studies the drug was given at 4 h in one group and at 2 h plus 4 h after blood loss in the second group. With the drug given at 3 or 4h, survival was 70% and 100% while in the 2h and the untreated groups it was 50%. Recovery was rapid in all the drug treated survivors, few became conscious within 30min. showed slight activity by 4-6 h, all were almost normally active by 24 and fully so by 72 h after ROWB. All the 5 control survivors remained unconscious/drowsy upto 24 h; 3 were sluggish at 72 h. By group analysis, serum iron elevation during the oligaemic and at the end of the post-oligaemic phase was less in the drug-treated animals. HP changes of shock in the liver studied by light microscopy, were markedly reduced in severity and were less prevalent in the drug-treated dogs. The salutory effects of desferrioxamine may be due to inhibition of iron catalyzed free-radical production and tissue damage, through its strong iron chelating action. It may have a therapeutic advantage in this emergency condition without the disadvantages of toxicity inherent in prolonged use. 相似文献
33.
Excessive activation of the hormone signaling pathways is implicated in several disorders of the target tissues, with cancer being one of the most serious fallouts. Steroid hormone receptors are key proteins through which steroid hormones convey their signals to the cells. Deregulated activity of the hormone receptors due to their altered activation; stability or sub-cellular localization is heavily implicated in the onset and progress of cancers. The role played by estrogen and its receptors in breast cancer remains the most thoroughly investigated steroid-dependent cancer system till date. Choosing it as an example, we have summarized the molecular mechanisms underlying the action of the estrogen receptors (ERs) in manifesting the effects of the estrogens in the cells. A special emphasis is placed on the molecular mechanism of their functionality, role of the coactivator proteins, and the reasons for the deregulated signaling. The therapeutic approaches resulting from the mechanistic study of the ER action and their efficacies are also discussed. 相似文献
34.
Johannsen MW Veedu RN Madsen AS Wengel J 《Bioorganic & medicinal chemistry letters》2012,22(10):3522-3526
The triphosphate of the thymine derivative of 2′-amino-LNA (2′-amino-LNA-TTP) was synthesised and found to be a good substrate for Phusion® HF DNA polymerase, allowing enzymatic synthesis of modified DNA encoded by an unmodified template. To complement this, 2′-amino-LNA-T phosphoramidites were incorporated into DNA oligonucleotides which were used as templates for enzymatic synthesis of unmodified DNA using either KOD, KOD XL or Phusion polymerases. 2′-Amino-LNA-T in the template and 2′-amino-LNA-TTP as a substrate both decreased reaction rate and yield compared to unmodified DNA, especially for sequences with multiple 2′-amino-LNA-T nucleotides. 相似文献
35.
Sondhi SM Goyal RN Lahoti AM Singh N Shukla R Raghubir R 《Bioorganic & medicinal chemistry》2005,13(9):3185-3195
Various 2-thiopyrimidine derivatives have been synthesized by an efficient, one-pot reaction of functionalized amines with either 4-isothiocyanato-4-methyl-2-pentanone or 3-isothiocyanatobutanal. All the synthesized compounds were fully characterized by elemental analysis (CHN), FT-IR, (1)H NMR, and mass spectral data. One of the compounds, 7,7,8a-trimethyl-hexahydro-thiazolo[3,2-c]pyrimidine-5-thione (17) showed good anti-inflammatory (37.4% at 100 mg/kg p.o.) and analgesic activity (75% at 100 mg/kg p.o.). 7-(1-Mercapto-3,3,4a-trimethyl-4,4a,5,9b-tetrahydro-3H-pyrido[4,3-b]indol-7-yl)-3,3,4a-trimethyl-3,4,4a,5-tetrahydro-benzo[4,5]imidazo[1,2-c]pyrimidine-1-thiol (3) showed moderate activity against CDK-1 (IC(50)=5 microM). The other compounds showed moderate anti-inflammatory (5-20%), analgesic (25-75%) and protein kinase (CDK-5, GSK-3) inhibitory activities (IC(50)> 10 microM). 相似文献
36.
Ismail M. Fareez Siong Meng Lim Nurul Aida Ashyqin Zulkefli Rakesh K. Mishra Kalavathy Ramasamy 《Probiotics and antimicrobial proteins》2018,10(3):543-557
The susceptibility of probiotics to low pH and high temperature has limited their use as nutraceuticals. In this study, enhanced protection of probiotics via microencapsulation was achieved. Lactobacillus plantarum LAB12 were immobilised within polymeric matrix comprised of alginate (Alg) with supplementation of cellulose derivatives (methylcellulose (MC), sodium carboxymethyl cellulose (NaCMC) or hydroxypropyl methylcellulose (HPMC)). L. plantarum LAB12 encapsulated in Alg-HPMC(1.0) and Alg-MC(1.0) elicited improved survivability (91%) in simulated gastric conditions and facilitated maximal release (~100%) in simulated intestinal condition. Alg-HPMC(1.0) and Alg-MC(1.0) significantly reduced (P < 0.05) the viability loss of LAB12 (viability loss <7%) when compared to Alg alone (viability loss <13%) under extreme temperatures (75 and 90 °C). Four-week storage of encapsulated LAB12 at 4 °C yielded viable counts >7 log CFU g?1. Alg-MC and Alg-HPMC improved the survival of LAB12 against simulated gastric condition (9.24 and 9.55 log CFU g?1, respectively), temperature up to 90 °C (9.54 and 9.86 log CFU g?1, respectively) and 4-week of storage at 4 °C (8.61 and 9.23 log CFU g?1, respectively) with sustained release of probiotic in intestinal condition (>9 log CFU g?1). These findings strongly suggest the potential of cellulose derivatives supplemented Alg bead as protective micro-transport for probiotic strains. They can be safely incorporated into new functional food or nutraceutical products. 相似文献
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38.
Vicky Wang-Wei Tsai Laurence Macia Heiko Johnen Tamara Kuffner Rakesh Manadhar Sebastian Beck J?rgensen Ka Ki Michelle Lee-Ng Hong Ping Zhang Liyun Wu Christopher Peter Marquis Lele Jiang Yasmin Husaini Shu Lin Herbert Herzog David A. Brown Amanda Sainsbury Samuel N. Breit 《PloS one》2013,8(2)
The TGF-b superfamily cytokine MIC-1/GDF15 circulates in all humans and when overproduced in cancer leads to anorexia/cachexia, by direct action on brain feeding centres. In these studies we have examined the role of physiologically relevant levels of MIC-1/GDF15 in the regulation of appetite, body weight and basal metabolic rate. MIC-1/GDF15 gene knockout mice (MIC-1−/−) weighed more and had increased adiposity, which was associated with increased spontaneous food intake. Female MIC-1−/− mice exhibited some additional alterations in reduced basal energy expenditure and physical activity, possibly owing to the associated decrease in total lean mass. Further, infusion of human recombinant MIC-1/GDF15 sufficient to raise serum levels in MIC-1−/− mice to within the normal human range reduced body weight and food intake. Taken together, our findings suggest that MIC-1/GDF15 is involved in the physiological regulation of appetite and energy storage. 相似文献
39.
Brian M.O. Ogendi Rakesh K. Bakshi Kanupriya Gupta Richa Kapil LaDraka T. Brown Stephen J. Jordan Steffanie Sabbaj Christen G. Press Jeannette Y. Lee William M. Geisler 《Microbes and infection / Institut Pasteur》2018,20(3):176-184
T cell phenotypes involved in the immune response to Chlamydia trachomatis (CT) have not been fully elucidated in humans. We evaluated differences in T cell phenotypes between CT-infected women and CT-seronegative controls and investigated changes in T cell phenotype distributions after CT treatment and their association with reinfection. We found a higher expression of T cell activation markers (CD38+HLA-DR+), T helper type 1 (Th1)- and Th2-associated effector phenotypes (CXCR3+CCR5+ and CCR4+, respectively), and T cell homing marker (CCR7) for both CD4+ and CD8+ T cells in CT-infected women. At follow-up after treatment of infected women, there were a lower proportion of CD4+ and CD8+ T cells expressing these markers. These findings suggest a dynamic interplay of CD4+ and CD8+ T cells in CT infection, and once the infection is treated, these cell markers return to basal expression levels. In women without reinfection, a significantly higher proportion of CD8+ T cells co-expressing CXCR3 with CCR5 or CCR4 at follow-up was detected compared to women with reinfection, suggesting they might play some role in adaptive immunity. Our study elucidated changes in T cell phenotypes during CT infection and after treatment, broadening our understanding of adaptive immune mechanisms in human CT infections. 相似文献
40.