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1.
K Tiku M L Tiku S Liu J L Skosey 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(10):3686-3692
In the course of our study on neutrophil production of an interleukin 1 (IL-1)-like factor, we found that the addition of polymorphonuclear neutrophils (PMN) to monocytes cultured in the presence of zymosan resulted in decreased IL 1 activity of the resultant supernatant, suggesting that PMN may contain an inhibitor of IL 1. The objective of this investigation was to study this IL 1 inhibitor which normal human PMN contain. The inhibitor is constitutively present in the PMN because 0 hr PMN lysates and unstimulated PMN supernatants also show inhibitory activity. The PMN inhibitor inhibits IL 1 (crude and partially purified) in a dose-response manner and does not affect basal [3H]thymidine incorporation in the presence or absence of PHA-P. The PMN inhibitor does not have any effect on interleukin 2 (IL 2)-induced proliferation of the IL 2-dependent CTLL cells. The inhibitor can be generated in the absence of serum and is not produced as a result of proteolytic activity from PMN enzymes. The inhibitor is heat-labile and is most stable at neutral pH. Gel filtration studies on Sephadex G-200 indicate that the inhibitor is heterogeneous in size. Two inhibitory peaks, at 45,000 to 70,000 m.w. and at greater than 160,000 m.w., were observed. When zymosan-stimulated PMN supernatant was chromatographed, there was separation of inhibitory factor from a 17,000 m.w. proliferating factor. Presence of this PMN inhibitor may be important in negative regulation of IL 1. 相似文献
2.
Kumar Varun Muthu Kumar S. P. Tiku Purnima Kaul 《International journal of peptide research and therapeutics》2021,27(4):2403-2415
International Journal of Peptide Research and Therapeutics - Elevation high plasma cholesterol plays a significant role in promoting the incidence of atherosclerosis and coronary heart disease. In... 相似文献
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Avinash Chandra Srivastava Ashok Kumar Tiku Madan Pal 《Acta Physiologiae Plantarum》2006,28(2):181-188
This study was conducted to determine reciprocal effects of low to high doses of nitrogenous fertilizer (N30, N40, N50, N60 and N70 — 30, 40, 50, 60 and 70 kg ha−1 respectively) and CO2 enriched environment on C and N partitioning in soybean (Glycine max (L.) Merril cv JS-335). Plants were grown from seedling emergence to maturity inside open top chambers under ambient, AC
(350±50 mol mol−1) and elevated, EC (600±50 mol mol−1) CO2 and analyzed at seedling, vegetative, flowering, pod setting and maturity stages. Soybean responded to both CO2 enrichment and N supply. Leaves, stem and root reserves at different growth stages were analyzed for total C and N contents.
Consistent increase in the C contents of the leaf, stem and root was observed under EC than in AC. N contents in the different
plant parts were found to be decreased under EC-grown plants specially at seedling and vegetative stage despite providing
N doses to the soil. Significant increase observed for C to N dry mass ratio under EC in the root, stems and leaves at seedling
and vegetative stage was decreased in the middle and later growth stages possibly due to combined impact of N doses to the
soil and increased N2 fixing activities due to EC conditions. Critical analysis of our findings reveals that the composition and partitioning of
C and N of soybean under variable rates of N supply and CO2 enrichment alter according to need under altered metabolic process. These changes eventually may lead to alteration in uptake
of not only N but other essential nutrients also under changing atmosphere. 相似文献
4.
Although the importance of radiation-induced adaptive response has been recognized in human health, risk assessment and clinical
application, the phenomenon has not been understood well in terms of survival of animals. To examine this aspect Swiss albino
mice were irradiated with different doses (2–10 Gy) at 0015 Gy/s dose rate and observed on a regular basis for 30 days. Since
almost 50% lethality was seen with 8 Gy, it was selected as the challenging dose for further studies. Irradiation of mice
with conditioning doses (0.25 or 0.5 Gy) and subsequent exposure to 8 Gy caused significant increase in the survival of mice
compared to irradiated control. The splitting of challenging dose did not influence the efficiency of conditioning doses (0.25
Gy and 0.5 Gy) to induce an adaptive response. However conditioning doses given in fractions (0.25 Gy + 0.25 Gy) or (0.5 Gy
+ 0.5 Gy) were able to modulate the response of challenging dose of 8 Gy. These results clearly showed the occurrence of adaptive
response in terms of survival of animals. The conditioning dose given in small fractions seemed to be more effective. The
findings have been discussed from a mechanistic point of view. The possible biological implications, potential medical benefits,
uncertainties and controversies related to adaptive response have also been addressed 相似文献
5.
Triploid plants of ornamental Phlox drummondii Hook. were raised from cultures of endosperm excised from immature fruits having zygotic embryo at early dicotyledonous stage. Endosperm tissue was firstly cultured with the embryo on the Murashige and Skoog’s (MS) medium supplemented with 5 μM 6-benzylaminopurine (BAP) + 10 μM α-napthaleneacetic acid (NAA) for 7 d and recultured after the embryo was removed. A friable callus appeared two weeks after removal of the embryo and it became compact callus mass in another three weeks. Upon transfer of this 5-week-old callus to the MS medium with 10 μM BAP + 2.5 μM indole-3-acetic acid (IAA), maximum percentage of green nodular shoot buds appeared from which regenerated dwarf shoots. Elongation of the dwarf shoots, however, required transfer of the individual dwarf shoots excised from the callus on the fresh medium and best results achieved on medium with low concentration of IAA (0.5 μM) in presence of 10 μM BAP. The shoots were then rooted in vitro and plants subsequently established in pots containing soil. Over 70 % of plants were triploid with a chromosome number of 2n=3x=21. Size of stem, leaves, flowers, pollen, and stomata of these triploid plants were higher and the plants were more vigorous as compared to naturally occurring diploid plants. In particular, flowers showed bright colour with enlarged central eye adding to their ornamental value. 相似文献
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Estimation of linear contrasts in experimental design, and testing their assumed values, is considered when the error distributions from block to block are not necessarily identical. The normal‐theory solutions are shown to have low efficiencies as compared to the solutions presented here. 相似文献
9.
Warshakoon NC Sheville J Bhatt RT Ji W Mendez-Andino JL Meyers KM Kim N Wos JA Mitchell C Paris JL Pinney BB Reizes O Hu XE 《Bioorganic & medicinal chemistry letters》2006,16(19):5207-5211
A novel series of substituted quinoline analogs were designed and synthesized as potent and selective melanin concentrating hormone (MCH) antagonists. These analogs show potent (nM) activity (12a-k) with a moderate selectivity. Conversely, the conformationally constrained thienopyrimidinone analogs (18a-g) showed improved activity in MCH-1R and selectivity over 5HT2C. 相似文献
10.
Arthritic diseases, such as osteoarthritis and rheumatoid arthritis, inflict an enormous health care burden on society. Osteoarthritis, a degenerative joint disease with high prevalence among older people, and rheumatoid arthritis, an autoimmune inflammatory disease, both lead to irreversible structural and functional damage to articular cartilage. The aim of this study was to investigate the effect of polyphenols such as catechin, quercetin, epigallocatechin gallate, and tannic acid, on crosslinking type II collagen and the roles of these agents in managing in vivo articular cartilage degradation. The thermal, enzymatic, and physical stability of bovine articular cartilage explants following polyphenolic treatment were assessed for efficiency. Epigallocatechin gallate and tannic acid-treated explants showed >12 °C increase over native cartilage in thermal stability, thereby confirming cartilage crosslinking. Polyphenol-treated cartilage also showed a significant reduction in the percentage of collagen degradation and the release of glycosaminoglycans against collagenase digestion, indicating the increase physical integrity and resistance of polyphenol crosslinked cartilage to enzymatic digestion. To examine the in vivo cartilage protective effects, polyphenols were injected intra-articularly before (prophylactic) and after (therapeutic) the induction of collagen-induced arthritis in rats. The hind paw volume and histomorphological scoring was done for cartilage damage. The intra-articular injection of epigallocatechin gallate and tannic acid did not significantly influence the time of onset or the intensity of joint inflammation. However, histomorphological scoring of the articular cartilage showed a significant reduction in cartilage degradation in prophylactic- and therapeutic-groups, indicating that intra-articular injections of polyphenols bind to articular cartilage and making it resistant to degradation despite ongoing inflammation. These studies establish the value of intra-articular injections of polyphenol in stabilization of cartilage collagen against degradation and indicate the unique beneficial role of injectable polyphenols in protecting the cartilage in arthritic conditions. 相似文献