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21.
Sharma Himanshu Bhandawat Abhishek Rahim Mohammed Saba Kumar Pankaj Choudhoury Mohini Pal Roy Joy 《Molecular biology reports》2020,47(5):3485-3500
Molecular Biology Reports - Introns experience lesser selection pressure, thus are liable for higher polymorphism. Intron Length Polymorphic (ILP) markers designed from exon-flanking introns... 相似文献
22.
Sharma Himanshu Kumar Pankaj Singh Abhishek Aggarwal Kanika Roy Joy Sharma Vikas Rawat Sandeep 《Molecular biology reports》2020,47(4):2447-2457
Molecular Biology Reports - The genus Rhododendron, known for large impressive flowers is widely distributed throughout the world. Rhododendrons have limited genetic information, despite of... 相似文献
23.
Various simple mathematical models have been used to investigate dengue transmission. Some of these models explicitly model the mosquito population, while others model the mosquitoes implicitly in the transmission term. We study the impact of modeling assumptions on the dynamics of dengue in Thailand by fitting dengue hemorrhagic fever (DHF) data to simple vector–host and SIR models using Bayesian Markov chain Monte Carlo estimation. The parameter estimates obtained for both models were consistent with previous studies. Most importantly, model selection found that the SIR model was substantially better than the vector–host model for the DHF data from Thailand. Therefore, explicitly incorporating the mosquito population may not be necessary in modeling dengue transmission for some populations. 相似文献
24.
A.H. Sardar S. Das S. Agnihorti M. Kumar A.K. Ghosh K. Abhishek A. Kumar B. Purkait M.Y. Ansari P. Das 《Experimental parasitology》2013
Antimicrobial peptides (AMPs) are multifunctional components of the innate immune system. Chemotherapeutic agents used for treatment of visceral leishmaniasis (VL) are now threatened due to the emergence of acquired drug resistance and toxicity. AMPs are attractive alternative to conventional pharmaceuticals. In this study, first time we explored the antileishmanial activity of spinigerin originally derived from Pseudacanthotermes spiniger. Leishmania donovani promastigotes present apoptosis-like cell death upon exposure to spinigerin (IC50, 150 μM). The infection rate was reduced by 20% upon exposure to 150 μM spinigerin but no cytotoxicity on host macrophages was observed. Elevation of intracellular ROS level and down-regulation of two ROS detoxifying enzymes, ascorbate peroxidase (APx) and trypanothione reductase (TR) suggested essential role of ROS machinery during spinigerin mediated cell death. About 97% cell population was found to be Annexin-V positive; 44% cells being highly Annexin-V positive. Moreover, we observed morphological changes like cell rounding, nuclear condensation, oligonucleosomal DNA degradation and TUNEL positive cells without loss of membrane integrity upon spinigerin exposure, suggests apoptosis-like death. Interestingly, collapse in mitochondrial membrane potential and increased level of intracellular ROS and calcium were not associated with caspase like activity. Computational analysis suggests spiningerin interacts with trypanothione reductase and thus probably interferes its function to detoxify the toxic ROS level. Therefore, spinigerin induces apoptosis-like cell death in L. donovani in a caspase-independent manner. The study elucidates the antileishmanial property of spinigerin that may be considered for future chemotherapeutic option alone or adjunct with other drug regimens for improved treatment of visceral leishmaniasis. 相似文献
25.
Extraction, thin-layer chromatography, and gas chromatography–mass spectrometry of leaf surface waxes of Momordica charantia L. (Cucurbitaceae) revealed that 20 n-alkanes between n-C15 and n-C36, except n-C34 and n-C35, commonly occur in young, mature, and senescent stages. Hentriacontane, hentriacontane, and hexatriacontane were the predominant compounds in young, mature, and senescent leaves, respectively. The cuticular alkanes from young, mature, and senescent leaves attracted the female insect, Epilachna dodecastigma (Wied.), at 25–400, 25–400, and 100–400 μg concentrations, respectively, whereas the mixtures of synthetic alkanes mimicking cuticular alkanes of young, mature, and senescent leaves showed attraction at 100–400, 100–400, and 200–400 μg concentrations, respectively, in Y-shaped glass tube olfactometer bioassay. The difference in insect attraction is probably due to the absence of branched-chain alkanes in the synthetic mixtures. Individual synthetic heptacosane, nonacosane, and hentriacontane at 28.19–56.90, 32.04–64.08, and 60.44–120.88 μg, respectively, elicited attraction of the insect. A synthetic blend of 4.82, 4.91, 5.71, 6.74, 56.39, 7.94, 62.42, 120.88, and 36.33 μg of nonadecane, eicosane, heneicosane, pentacosane, heptacosane, octacosane, nonacosane, hentriacontane, and tritriacontane, respectively, was most attractive to the insect. 相似文献
26.
Shailendra Kumar Dhar Dwivedi Krishnananda Samanta Manisha Yadav Amit Kumar Jana Abhishek Kumar Singh Bandana Chakravarti Sankalan Mondal Rituraj Konwar Arun Kumar Trivedi Naibedya Chattopadhyay Sabyasachi Sanyal Gautam Panda 《Bioorganic & medicinal chemistry letters》2013,23(24):6816-6821
Two series of new benzoxazepines substituted with different alkyl amino ethyl chains were synthesized comprising synthetic steps of inter and intramolecular Mitsunobu reaction, lithium aluminium hydride (LAH) reduction, debenzylation, bimolecular nucleophilic substitution (SN2) reaction. The present study investigates the effect of a tyrosine-based benzoxazepine derivative in human breast cancer cells MCF-7 and MDA-MB-231 and in breast cancer animal model. The anti-proliferative effect of 15a on MCF-7 cells was associated with G1 cell-cycle arrest. This G1 growth arrest was followed by apoptosis as 15a dose dependently increased phosphatidylserine exposure, PARP cleavage and DNA fragmentation that are hallmarks of apoptotic cell death. Interestingly, 15a activated components of both intrinsic and extrinsic pathways of apoptosis characterized by activation of caspase-8 and -9, mitochondrial membrane depolarization and increase in Bax/Bcl2 ratio. However, use of selective caspase inhibitors revealed that the caspase-8-dependent pathway is the major contributor to 15a-induced apoptosis. Compound 15a also significantly reduced the growth of MCF-7 xenograft tumors in athymic nude mice. Together, 15a could serve as a base for the development of a new group of effective breast cancer therapeutics. 相似文献
27.
28.
Background
Obesity is considered as a systemic chronic low grade inflammation characterized by increased serum pro-inflammatory proteins and accumulation of macrophages within white adipose tissue (WAT) of obese patients. C5L2, a 7-transmembrane receptor, serves a dual function, binding the lipogenic hormone acylation stimulating protein (ASP), and C5a, involved in innate immunity.Aim
We evaluated the impact of C5L2 on macrophage infiltration in WAT of wildtype (Ctl) and C5L2 knock-out (C5L2−/−) mice over 6, 12 and 24 weeks on a chow diet and moderate diet-induced obesity (DIO) conditions.Results
In Ctl mice, WAT C5L2 and C5a receptor mRNA increased (up to 10-fold) both over time and with DIO. By contrast, in C5L2−/−, there was no change in C5aR in WAT. C5L2−/− mice displayed higher macrophage content in WAT, varying by time, fat depot and diet, associated with altered systemic and WAT cytokine patterns compared to Ctl mice. However, in all cases, the M1 (pro-) vs M2 (anti-inflammatory) macrophage proportion was unchanged but C5L2−/− adipose tissue secretome appeared to be more chemoattractant. Moreover, C5L2−/− mice have increased food intake, increased WAT, and altered WAT lipid gene expression, which is reflected systemically. Furthermore, C5L2−/− mice have altered glucose/insulin metabolism, adiponectin and insulin signalling gene expression in WAT, which could contribute to development of insulin resistance.Conclusion
Disruption of C5L2 increases macrophage presence in WAT, contributing to obesity-associated pathologies, and further supports a dual role of complement in WAT. Understanding this effect of the complement system pathway could contribute to targeting treatment of obesity and its comorbidities. 相似文献29.
Every individual varies in character and so do their sensory functions and perceptions. The molecular mechanism and the molecular candidates involved in these processes are assumed to be similar if not same. So far several molecular factors have been identified which are fairly conserved across the phylogenetic tree and are involved in these complex sensory functions. Among all, members belonging to Transient Receptor Potential (TRP) channels have been widely characterized for their involvement in thermo-sensation. These include TRPV1 to TRPV4 channels which reveal complex thermo-gating behavior in response to changes in temperature. The molecular evolution of these channels is highly correlative with the thermal response of different species. However, recent 2504 human genome data suggest that these thermo-sensitive TRPV channels are highly variable and carry possible deleterious mutations in human population. These unexpected findings may explain the individual differences in terms of complex sensory functions. 相似文献
30.
Akansha Mohan Aaron J. Roberto Abhishek Mohan Aileen Lorenzo Kathryn Jones Martin J. Carney Luis Liogier-Weyback Soonjo Hwang Kyle A.B. Lapidus 《The Yale journal of biology and medicine》2016,89(1):49-57
The relationship of cortical structure and specific neuronal circuitry to global brain function, particularly its perturbations related to the development and progression of neuropathology, is an area of great interest in neurobehavioral science. Disruption of these neural networks can be associated with a wide range of neurological and neuropsychiatric disorders. Herein we review activity of the Default Mode Network (DMN) in neurological and neuropsychiatric disorders, including Alzheimer’s disease, Parkinson’s disease, Epilepsy (Temporal Lobe Epilepsy - TLE), attention deficit hyperactivity disorder (ADHD), and mood disorders. We discuss the implications of DMN disruptions and their relationship to the neurocognitive model of each disease entity, the utility of DMN assessment in clinical evaluation, and the changes of the DMN following treatment. 相似文献