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81.
Swarup Roy Choudhury Mao Li Veronica Lee Raja Sekhar Nandety Kirankumar S. Mysore Sona Pandey 《The Plant journal : for cell and molecular biology》2020,102(2):207-221
Plants being sessile integrate information from a variety of endogenous and external cues simultaneously to optimize growth and development. This necessitates the signaling networks in plants to be highly dynamic and flexible. One such network involves heterotrimeric G‐proteins comprised of Gα, Gβ, and Gγ subunits, which influence many aspects of growth, development, and stress response pathways. In plants such as Arabidopsis, a relatively simple repertoire of G‐proteins comprised of one canonical and three extra‐large Gα, one Gβ and three Gγ subunits exists. Because the Gβ and Gγ proteins form obligate dimers, the phenotypes of plants lacking the sole Gβ or all Gγ genes are similar, as expected. However, Gα proteins can exist either as monomers or in a complex with Gβγ, and the details of combinatorial genetic and physiological interactions of different Gα proteins with the sole Gβ remain unexplored. To evaluate such flexible, signal‐dependent interactions and their contribution toward eliciting a specific response, we have generated Arabidopsis mutants lacking specific combinations of Gα and Gβ genes, performed extensive phenotypic analysis, and evaluated the results in the context of subunit usage and interaction specificity. Our data show that multiple mechanistic modes, and in some cases complex epistatic relationships, exist depending on the signal‐dependent interactions between the Gα and Gβ proteins. This suggests that, despite their limited numbers, the inherent flexibility of plant G‐protein networks provides for the adaptability needed to survive under continuously changing environments. 相似文献
82.
The purpose of this research was to develop the hydrodynamically balanced delivery system of Clarithromycin (CLA) which, after
oral administration should have the ability to prolong gastric residence time with the desired in vitro release profile for the localized action in the stomach, in the treatment of Helicobacter pylori (H.pylori) mediated peptic ulcer. By applying wet granulation technique floating tablets of Clarithromycin were prepared.
The proportion of sodium bicarbonate was varied to get the least possible lag time, also the polymer part varied to get the
desired release. In vivo radiographic studies were performed with Barium sulphate loaded formulation to justify the increased gastric residence time
of the dosage form in the stomach, based on the floating principle. The formulation developed using 66.2% Clarithromycin,
12% HPMC K4M polymer, 8% sodium bicarbonate gave floating lag time less than 3 min with a floating time of 12 h, and an in vitro release profile very near to the desired release. X-ray studies showed the enhanced gastric residence time of the tablet
to 220 ± 30 min. The mechanism of release of Clarithromycin from the floating tablets is anomalous diffusion transport and
follows zero order kinetics. In vivo radiographic studies suggest that the tablet has increased gastric residence time for the effective localized action of the
antibiotic (Clarithromycin) in the treatment of H.pylori mediated peptic ulcer. 相似文献
83.
84.
Panthangi Seshapani Daddam Jayasimha Rayalu Vadde Kiran Kumar Kathera Chandra Sekhar Jasti Pramoda Kumari 《Bioinformation》2013,9(9):485-490
Differently expressed proteins in probiotic Escherichia coli nissle 1917 under mercury stress identified by using a proteomic
approach. We applied to separate proteins by using two-dimensional gel electrophoresis and proteins were identified using
MALDI-TOF-MS using PMF, by mascot database search using the NCBI database. we identified six proteins after exposure to
mercury stress with respect to different functional classes. It is useful to understand the molecular insights into mercury stress in
probiotic E. coli. Next we describe a structure generated by homology modelling and functional domain identification; it is
interesting to study the impact of stress on protein structures. MS characterization and computational methods together provide
the opportunity to examine the impact of stress arising from mercury. The role of these proteins in metal tolerance and structure
relation is discussed. To the best of our knowledge, proteomics of E. coli nissle 1917 overview of mercury stress has been reported
for the first time. 相似文献
85.
86.
A novel enediynyl pentapeptide in the protected form 1 was synthesized and characterized. It exists predominantly in beta-turn structural motif as revealed by variable temperature NMR and CD spectroscopy. In the presence of transition metal ions and gold nanoparticles, the fluorescence intensity of the peptide got enhanced with remarkable quantum yield with the Z-enediynyl -amino acid acting as a fluorophoric reporter. The interesting photophysical behaviors with alkali and alkaline earth metal ions are also reported. 相似文献
87.
P.?K.?Krishnan?NambooriEmail author K.?V.?Vineeth V.?Rohith Ibnul?Hassan Lekshmi?Sekhar Akhila?Sekhar M.?Nidheesh 《Functional & integrative genomics》2011,11(4):519-522
The ApoE gene responsible for the Alzheimer's disease has been examined to identify functional consequences of single-nucleotide
polymorphisms (SNPs). Eighty-eight SNPs have been identified in the ApoE gene in which 31 are found to be nonsynonymous, 8
of them are coding synonymous, 33 are found to be in intron, and 3 are in untranslated region. The SNPs found in the untranslated
region consisted of two SNPs from 5′ and one SNP from the 3′. Twenty-nine percent of the identified nsSNPs have been reported
as damaging. In the analysis of SNPs in the UTR regions, it has been recognized that rs72654467 from 5′ and rs71673244 from
5′ and 3′ are responsible for the alteration in levels of expression. Both native and mutant protein structures were analyzed
along with the stabilization residues. It has been concluded that among all SNPs of ApoE, the mutation in rs11542041 (R132S)
has the most significant effect on functional variation. 相似文献
88.
Accurate identification of protein-coding regions (exons) in DNA sequences has been a challenging task in bioinformatics. Particularly the coding regions have a 3-base periodicity, which forms the basis of all exon identification methods. Many signal processing tools and techniques have been applied successfully for the identification task but still improvement in this direction is needed. In this paper, we have introduced a new promising model-independent time-frequency filtering technique based on S-transform for accurate identification of the coding regions. The S-transform is a powerful linear time-frequency representation useful for filtering in time-frequency domain. The potential of the proposed technique has been assessed through simulation study and the results obtained have been compared with the existing methods using standard datasets. The comparative study demonstrates that the proposed method outperforms its counterparts in identifying the coding regions. 相似文献
89.
Kirat Kumar Ganguly Sekhar Pal Shuvojit Moulik Amitava Chatterjee 《Cell Adhesion & Migration》2013,7(3):251-261
Metastasis is a combination of biological events that makes the difference between cancer and other diseases. Metastasis requires flow of erroneous but precisely coordinated basic cellular activities like cell migration–invasion, cell survival–apoptosis, cell proliferation, etc. All of these processes require efficient regulation of cell attachment and detachment, which recruit integrin receptors in this flow of events. World literatures show several aspects of interrelation of integrins and metastasis. Integrin molecules are being used as prime target to battle metastasis. In this review we are collating the observations showing importance of integrin biology in regulation of metastasis and the strategies where integrin receptors are being used as targets to regulate metastasis. 相似文献
90.
Linda Neuhauser Susan L. Ivey Debbie Huang Alina Engelman Winston Tseng Donna Dahrouge Sidhanta Gurung Melissa Kealey 《PloS one》2013,8(2)
A major public health challenge is to communicate effectively with vulnerable populations about preparing for disasters and other health emergencies. People who are Deaf or Hard of Hearing (Deaf/HH) and older adults are particularly vulnerable during health emergencies and require communications that are accessible and understandable. Although health literacy studies indicate that the readability of health communication materials often exceeds people’s literacy levels, we could find no research about the readability of emergency preparedness materials (EPM) intended for Deaf/HH and older adult populations. The objective of this study was to explore issues related to EPM for Deaf/HH and older adult populations, to assess the availability and readability of materials for these populations, and to recommend improvements. In two California counties, we interviewed staff at 14 community-based organizations (CBOs) serving Deaf/HH clients and 20 CBOs serving older adults selected from a stratified, random sample of 227 CBOs. We collected 40 EPM from 10 CBOs and 2 public health departments and 40 EPM from 14 local and national websites with EPM for the public. We used computerized assessments to test the U.S. grade reading levels of the 16 eligible CBO and health department EPM, and the 18 eligible website materials. Results showed that less than half of CBOs had EPM for their clients. All EPM intended for clients of Deaf/HH-serving CBOs tested above the recommended 4th grade reading level, and 91% of the materials intended for clients of older adult-serving CBOs scored above the recommended 6th grade level. EPM for these populations should be widely available through CBOs and public health departments, adhere to health literacy principles, and be accessible in alternative formats including American Sign Language. Developers should engage the intended users of EPM as co-designers and testers. This study adds to the limited literature about EPM for these populations. 相似文献