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61.
Paromita Saha Anjan K. Nandi Sruthi Unnikrishnan M. C. Shilpa Shantanu P. Shukla Souvik Mandal Aniruddha Mitra Raghavendra Gadagkar 《Journal of Insect Behavior》2018,31(1):54-65
Insect societies are hallmarks of cooperation because one or a few queens monopolize reproduction and several non-reproductive workers cooperatively raise brood. However, the loss of the queen exposes a colony to potential reproductive conflict, which is resolved only after a new queen takes over. We studied queen succession in natural and experimental colonies of the primitively eusocial wasp Ropalidia marginata to understand the proximate behavioral strategies involved in the resolution of this conflict. Previous work has shown that in this species, experimental queen removal always results in only one worker becoming hyper-aggressive and taking over the colony as its next queen, without ever being challenged. Here we show that even during natural queen turnover, one and only one worker becomes hyper-aggressive and takes over as the next queen, without being challenged. During natural queen turn-over, aggression of the successor may sometimes begin before the loss of the old queen and may sometimes decline more rapidly, unlike in the case of experimental queen removal. The successor begins to lay eggs sooner after a natural queen turn-over as compared to experimental queen removal. This is expected because workers might detect the gradual decline of the queen preceding her disappearance. Because queen succession is expected to be more prevalent in tropical perennial species, we expect natural selection to have favored such an orderly queen succession so that a route to direct fitness is available without significant reduction in cooperation. 相似文献
62.
Abhay R. Redkar Shilpa Kadam Madhav G. Deo Rita Mulherkar 《Journal of biosciences》1997,22(5):529-536
Enhancing factor (EF), a mouse phospholipase A2 (PLA2), has been purified from the small intestines, based on its ability to increase the binding of epidermal growth factor in
a radioreceptor assay. EF/PLA2 was found to be localized predominantly in the Paneth cells in the small intestines. Whether mouse intestinal EF/PLA2 is identical/similar to mouse secretory PLA2 was to be determined. Phospholipases are known to play a crucial role in the process of inflammation. This paper reports
the presence of trace amounts of EF/PLA2 in the peritoneal exudate cells. Western blot analysis of the acid extracts showed the presence of a 14 kDa immunologically
cross-reactive protein. RT-PCR analysis using EF specific primers amplified a ∼700 bp product which was further confirmed
to be EF-specific by nested PCR analysis and sequencing. Presence of EF in the peritoneal exudate cells could be a unique
mode of transport of growth factor modulator to the site of injury to aid in regeneration/cell proliferation of damaged tissue. 相似文献
63.
Shilpa Raghuvanshi Reena Gupta 《Journal of industrial microbiology & biotechnology》2009,36(3):401-407
Extracellular lipase from Bacillus coagulans BTS-3 was immobilized on (3 Å × 1.5 mm) molecular sieve. The molecular sieve showed approximately 68.48% binding efficiency for lipase (specific activity 55 IU mg?1). The immobilized enzyme achieved approx 90% conversion of acetic acid and 4-nitrophenol (100 mM each) into 4-nitrophenyl acetate in n-heptane at 65°C in 3 h. When alkane of C-chain length other than n-heptane was used as the organic solvent, the conversion of 4-nitrophenol and acetic acid was found to decrease. About 88.6% conversion of the reactants into ester was achieved when reactants were used at molar ratio of 1:1. The immobilized lipase brought about conversion of approximately 58% for esterification of 4-nitrophenol and acetic acid into 4-nitrophenyl acetate at a temperature of 65°C after reuse for 5 cycles. 相似文献
64.
Effects of pH and low density lipoprotein (LDL) on PCSK9-dependent LDL receptor regulation 总被引:2,自引:0,他引:2
65.
Patil Prakash G. Jamma Shivani M. Singh N. V. Bohra Abhishek Parashuram Shilpa Injal Archana S. Gargade Vaishali A. Chakranarayan Manasi G. Salutgi Unnati D. Dhinesh Babu K. Sharma Jyotsana 《Physiology and Molecular Biology of Plants》2020,26(6):1249-1261
Physiology and Molecular Biology of Plants - The present study investigates the genetic diversity and population structure among 42 diverse pomegranate genotypes using a set of twenty one class I... 相似文献
66.
A bioactive peptide of 8595 Da was purified from the cell free supernatant of Lactococcus garvieae subsp. bovis BSN307T. MALDI MS/MS peptide mapping and the data base search displayed no significant similarity to any reported antimicrobial peptide of LAB. This peptide at a dose concentration of 200 µg ml−1 inhibited the growth of both Gram-positive and Gram-negative bacteria by 58–89% and a dose of 500 µg ml−1 scavenged 50% of DPPH-free radicals generated. Interestingly, cytotoxicity assay demonstrated that 17 µg ml−1 of peptide selectively inhibited 50% proliferation of mammalian cancer cell lines HeLa and MCF-7 whereas normal H9c2 cells remained unaffected. Fluorescent microscopic analysis after DAPI nuclear staining of HeLa cells showed characteristics of apoptosis and activation of caspase-3 was ascertained by caspase-3 fluorescence assay. 相似文献
67.
Sivaprasad Kasturi Sujatha Surarapu Srinivas Uppalanchi Jaya Shree Anireddy Shubham Dwivedi Hasitha Shilpa Anantaraju Yogeeswari Perumal Dilep Kumar Sigalapalli Bathini Nagendra Babu Krishna S. Ethiraj 《Bioorganic & medicinal chemistry letters》2017,27(12):2818-2823
A new series of Deacetylsarmentamide A and B derivatives, amides and sulfonamides of 3,4-dihydroxypyrrolidines as α-glucosidase inhibitors were designed and synthesized. The biological screening test against α-glucosidase showed that some of these compounds have the positive inhibitory activity against α-glucosidase. Saturated aliphatic amides were more potent than the olefinic amides. Among all the compounds, 5o/6o having polar –NH2 group, 10f/11f having polar –OH group on phenyl ring displayed 3–4-fold more potent than the standard drugs. Acarbose, Voglibose and Miglitol were used as standard references. The promising compounds 6i, 5o, 6o, 10a, 11a, 10f and 11f have been identified. Molecular docking simulations were done for compounds to identify important binding modes responsible for inhibition activity of α-glucosidase. 相似文献
68.
Ahson Wardak Michael E. Gorman Nathan Swami Shilpa Deshpande 《Journal of Industrial Ecology》2008,12(3):435-448
In order to realize the projected market potential of nanotechnology, the environmental, health, and safety (EHS) uncertainties posed by a nano‐product (i.e., a nanotechnology‐enabled product) need to be characterized through the identification of risks and opportunities in early stages of product development. We present a methodology to identify risks from nano‐products using a scenario analysis approach that allows for expert elicitation on a set of preidentified use and disposal scenarios and what we have labeled “risk triggers” to obtain scores on their likelihood of occurrence and severity. Use and disposal scenarios describe product life‐cycle stages that could result in risk attributed to the nano‐product, whereas risk triggers are particular to nanoparticle properties. These are potential risks, as the risk assessment community is currently debating the specific risks attributed to nanotechnology. Through such a framework, our goal is to identify which products pose greater risks, where these risks occur in the product life cycle, and the impacts of these environmental risks on society. The comparison of risk triggers across nano‐products allows relative risk ranking on axes of exposure‐ and hazard‐related risk triggers. For the specific case of air fresheners, areas of acute risks resulted from bioavailability of nanoparticles in air release and water entrainment exposure scenarios; catalytic activity of nanoparticles in inhalation and air release exposure scenarios; the harmful effects due to the antibacterial property on useful bacteria particularly in susceptible populations; and, finally, risks from the lack of nanoparticle coating stability in air release scenarios. 相似文献
69.
Kim B Sarangi PP Azkur AK Kaistha SD Rouse BT 《Microbes and infection / Institut Pasteur》2008,10(3):302-312
Herpes simplex virus (HSV) infection of the cornea culminates in an immunopathological lesion (stromal keratitis--SK) that impairs vision. This report shows that HSV infection results in IL-23 up-regulation, but if this response fails to occur, as was noted in p19-/- mice, the severity of lesions, their incidence and the level of viral induced angiogenesis were significantly increased compared to wild-type (WT) animals (p<0.05). The higher disease severity in p19-/- mice appeared to be the consequence of an increased IL-12 response that in turn led to the induction of higher numbers of IFN-gamma producing CD4(+)T cells, the principal orchestrators of SK. Our results indicate that the severity of HSV induced immunopathological lesions may be mainly the consequence of IL-12 driven Th1 T cell reactions rather than the action of IL-17 producing cells controlled by IL-23. 相似文献
70.
Jones B Su H Bhat A Lei H Bajko J Hevi S Baltus GA Kadam S Zhai H Valdez R Gonzalo S Zhang Y Li E Chen T 《PLoS genetics》2008,4(9):e1000190
Dot1 is an evolutionarily conserved histone methyltransferase specific for lysine 79 of histone H3 (H3K79). In Saccharomyces cerevisiae, Dot1-mediated H3K79 methylation is associated with telomere silencing, meiotic checkpoint control, and DNA damage response. The biological function of H3K79 methylation in mammals, however, remains poorly understood. Using gene targeting, we generated mice deficient for Dot1L, the murine Dot1 homologue. Dot1L-deficient embryos show multiple developmental abnormalities, including growth impairment, angiogenesis defects in the yolk sac, and cardiac dilation, and die between 9.5 and 10.5 days post coitum. To gain insights into the cellular function of Dot1L, we derived embryonic stem (ES) cells from Dot1L mutant blastocysts. Dot1L-deficient ES cells show global loss of H3K79 methylation as well as reduced levels of heterochromatic marks (H3K9 di-methylation and H4K20 tri-methylation) at centromeres and telomeres. These changes are accompanied by aneuploidy, telomere elongation, and proliferation defects. Taken together, these results indicate that Dot1L and H3K79 methylation play important roles in heterochromatin formation and in embryonic development. 相似文献