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581.
Prabodh Kapoor Ashutosh Kumar Rangeetha Naik Munia Ganguli Mohammad I. Siddiqi Amogh A. Sahasrabuddhe Chhitar M. Gupta 《Nucleic acids research》2010,38(10):3308-3317
Leishmania actin (LdACT) is an unconventional form of eukaryotic actin in that it markedly differs from other actins in terms of its filament forming as well as toxin and DNase-1-binding properties. Besides being present in the cytoplasm, cortical regions, flagellum and nucleus, it is also present in the kinetoplast where it appears to associate with the kinetoplast DNA (kDNA). However, nothing is known about its role in this organelle. Here, we show that LdACT is indeed associated with the kDNA disc in Leishmania kinetoplast, and under in vitro conditions, it specifically binds DNA primarily through electrostatic interactions involving its unique DNase-1-binding region and the DNA major groove. We further reveal that this protein exhibits DNA-nicking activity which requires its polymeric state as well as ATP hydrolysis and through this activity it converts catenated kDNA minicircles into open form. In addition, we show that LdACT specifically binds bacterial type II topoisomerase and inhibits its decatenation activity. Together, these results strongly indicate that LdACT could play a critical role in kDNA remodeling. 相似文献
582.
Sejal Desai Amlan Barai Amirali B. Bukhari Abhijit De Shamik Sen 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2018,1865(1):196-208
Acquired radioresistance accompanied with increased metastatic potential is a major hurdle in effective radiotherapy of breast cancers. However, the nature of their inter-dependence and the underlying mechanism remains largely intangible. By employing radioresistant (RR) cell lines, we herein demonstrate that MCF-7 RR cells display phenotypic and molecular alterations evocative of epithelial to mesenchymal transition (EMT) with increased traction forces and membrane ruffling culminating in boosted invasiveness. We then show that these changes can be attributed to overexpression of alpha-actinin-4 (ACTN4), with ACTN4 knockdown near-completely abrogating both radioresistance and EMT-associated changes. We further found that in MCF-7 RR cells, ACTN4 mediates the observed effects by activating AKT, and downstream AKT/GSK3β signalling. Though ACTN4 plays a similar role in mediating radioresistance and invasiveness in MDA-MB-231 RR cells, co-immunoprecipitation studies reveal that these changes are effected through increased association with AKT and not by overexpression of AKT. Taken together, our study identifies ACTN4/AKT/GSK3β as a novel pathway regulating radioresistance coupled invasion which can be further explored to improve the radiotherapeutic gain. 相似文献
583.
U. Krishna A.C. Ganguli A.V. Mandlekar V.N. Purandare 《Prostaglandins & other lipid mediators》1978,15(4):685-693
Prostaglandin F2α and its methyl analogues were used for induction of abortion in 598 patients with gestational age from 9 to 20 weeks. Different routes of administration were studied and varous dosages given. The incidence of gastrointestinal side effects were within acceptable range for all methods. Both intra-amniotic injections of 50 mg PGF2α and 2.5 mg 15-methyl PGF2α as well as intramuscular and vaginal administration of 15-methyl PGF2α or its methyl ester, respectively, were highly effective in termination of pregnancy. The intramuscular route was, however, associated with the highest frequency of gastrointestinal side effects. If both efficacy and side effects were taken into consideration, the intra-amniotic and vaginal routes were superior. The ease of administration as well as the applicability over a wider range of gestation in termination of pregnancy may, however, in many situations speak in favour of the repeated vaginal administration of 15-methyl PGF2α methyl ester. 相似文献
584.
Shawn Thatcher Mark Jung Gayathri Panangipalli Kevin Fengler Abhijit Sanyal Bailin Li Victor Llaca Jeffrey Habben 《Molecular Plant Pathology》2023,24(7):742-757
Plant pathogens cause significant crop loss worldwide, and new resistance genes deployed to combat diseases can be overcome quickly. Understanding the existing resistance gene diversity within the germplasm of major crops, such as maize, is crucial for the development of new disease-resistant varieties. We analysed the nucleotide-binding leucine-rich repeat receptors (NLRs) of 26 recently sequenced diverse founder lines from the maize nested association mapping (NAM) population and compared them to the R gene complement present in a wild relative of maize, Zea luxurians. We found that NLRs in both species contain a large diversity of atypical integrated domains, including many domains that have not previously been found in the NLRs of other species. Additionally, the single Z. luxurians genome was found to have greater integrated atypical domain diversity than all 26 NAM founder lines combined, indicating that this species may represent a rich source of novel resistance genes. NLRs were also found to have very high sequence diversity and presence–absence variation among the NAM founder lines, with a large NLR cluster on Chr10 representing a diversity hotspot. Additionally, NLRs were shown to be mobile within maize genomes, with several putative interchromosomal translocations identified. 相似文献
585.
Abhijit Chandra Roy Shreyas Bangalore Subramanya Shoorashetty Manohar Rudresh Venkatakrishnan Venkataraman 《Journal of biophotonics》2021,14(3):e202000381
We present an on chip optofluidic surface deformable liquid Dove prism (LDP) based low-fluid flow pressure monitoring device. The unique design of the device in combination with liquid and soft solid enabled by the total internal reflection of light makes the sensor highly sensitive and compatible with the integration of a microfluidic and/or Lab-on-a-chip device. A layer-by-layer soft lithographic (LSL) and 3D printing technique are exploited to make the device. We have used Polydimethylsiloxane (PDMS) as the layer material and two variety of liquids (a) immersion oil (IO) and (b) di-iodomethane (DI) as refracting medium to construct the LDP sensor. Optical ray tracing simulation is performed to optimize the sensor. The pressure sensor shows sensitivity as high as ±28.5 mV per 50 Pa pressure with an error ± 2.5 mV and repeatability of ~99.56% at full scale. We have shown the applicability of the sensor by capturing and analyzing respiratory pressure signals of some human subjects at numerous conditions. 相似文献
586.
Taylor Moot Ashley R. Marshall Lance M. Wheeler Severin N. Habisreutinger Tracy H. Schloemer Caleb C. Boyd Desislava R. Dikova Gregory F. Pach Abhijit Hazarika Michael D. McGehee Henry J. Snaith Joseph M. Luther 《Liver Transplantation》2020,10(9)
The excellent optoelectronic properties demonstrated by hybrid organic/inorganic metal halide perovskites are all predicated on precisely controlling the exact nucleation and crystallization dynamics that occur during film formation. In general, high‐performance thin films are obtained by a method commonly called solvent engineering (or antisolvent quench) processing. The solvent engineering method removes excess solvent, but importantly leaves behind solvent that forms chemical adducts with the lead‐halide precursor salts. These adduct‐based precursor phases control nucleation and the growth of the polycrystalline domains. There has not yet been a comprehensive study comparing the various antisolvents used in different perovskite compositions containing cesium. In addition, there have been no reports of solvent engineering for high efficiency in all‐inorganic perovskites such as CsPbI3. In this work, inorganic perovskite composition CsPbI3 is specifically targeted and unique adducts formed between CsI and precursor solvents and antisolvents are found that have not been observed for other A‐site cation salts. These CsI adducts control nucleation more so than the PbI2–dimethyl sulfoxide (DMSO) adduct and demonstrate how the A‐site plays a significant role in crystallization. The use of methyl acetate (MeOAc) in this solvent engineering approach dictates crystallization through the formation of a CsI–MeOAc adduct and results in solar cells with a power conversion efficiency of 14.4%. 相似文献
587.
In wheat seed the scutellum plays an important role in the hydrolysisof stored substrate during germination. This layer is activatedfirst, whilst the aleurone becomes activated later. A good correlationexists between the initiation of visible germination and theappearance of enzyme activity in the scutellum. Enzyme activityin the aleurone becomes apparent only when the germinating seedlingreaches the rapid growth phase. Electron microscopic observationsshow that during the later stages of germination the scutellarcells develop finger like projections. These may serve to absorbendospermic reserves hydrolysed by aleurone amylase. The scutellumof aged non-germinating seeds showed no amylase activity andno finger like projections were produced even after prolongedimbibition.Copyright 1993, 1999 Academic Press Wheat (Triticum aestivum L.), deteriorated, germination, scutellum, scanning electron microscopy, aleurone 相似文献
588.
589.
Homogenization of fresh rat livers in 0.5mM cupric sulfate and 0.5% sodium dodecyl sulfate yielded both RNA and DNA in the aqueous phase after treatment vith phenol at 0–4°C. Effective deproteinization was achieved by three additional phenol treatments. Nucleic acids vere freed from Cu2+by repeated precipitation with ethanol in the presence of EDTA. The final yield was 6–7 mg/g of liver, of which about 20% was DNA and 11% tRNA. Physicochenical studies showed that pure tRNA, undegraded rRKA (30S, 18S) and native DNA (s°20, w = 24.4S) were isolated by this procedure. 相似文献
590.
Shinjini Bandopadhyay Sujata Mandal Mimosa Ghorai Niraj Kumar Jha Manoj Kumar Radha Arabinda Ghosh Jarosław Proćków José M. Pérez de la Lastra Abhijit Dey 《Journal of cellular and molecular medicine》2023,27(5):593-608
Centella asiatica is an ethnomedicinal herbaceous species that grows abundantly in tropical and sub-tropical regions of China, India, South-Eastern Asia and Africa. It is a popular nutraceutical that is employed in various forms of clinical and cosmetic treatments. C. asiatica extracts are reported widely in Ayurvedic and Chinese traditional medicine to boost memory, prevent cognitive deficits and improve brain functions. The major bioactive constituents of C. asiatica are the pentacyclic triterpenoid glycosides, asiaticoside and madecassoside, and their corresponding aglycones, asiatic acid and madecassic acid. Asiaticoside and madecassoside have been identified as the marker compounds of C. asiatica in the Chinese Pharmacopoeia and these triterpene compounds offer a wide range of pharmacological properties, including neuroprotective, cardioprotective, hepatoprotective, wound healing, anti-inflammatory, anti-oxidant, anti-allergic, anti-depressant, anxiolytic, antifibrotic, antibacterial, anti-arthritic, anti-tumour and immunomodulatory activities. Asiaticoside and madecassoside are also used extensively in treating skin abnormalities, burn injuries, ischaemia, ulcers, asthma, lupus, psoriasis and scleroderma. Besides medicinal applications, these phytocompounds are considered cosmetically beneficial for their role in anti-ageing, skin hydration, collagen synthesis, UV protection and curing scars. Existing reports and experimental studies on these compounds between 2005 and 2022 have been selectively reviewed in this article to provide a comprehensive overview of the numerous therapeutic advantages of asiaticoside and madecassoside and their potential roles in the medical future. 相似文献