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1.
Earu Banoth Vamshi Krishna Kasula Veerendra Kalyan Jagannadh Sai Siva Gorthi 《Journal of biophotonics》2016,9(6):610-618
In this work, an optofluidic flow analyzer, which can be used to perform malaria diagnosis at the point‐of‐care is demonstrated. The presented technique is based on quantitative optical absorption measurements carried out on a single cell level for a given population of Human Red Blood Cells (RBCs). By measuring the optical absorption of each RBC, the decrease in the Hemoglobin (Hb) concentration in the cytoplasm of the cell due to the invasion of malarial parasite is detected. Cells are assessed on a single cell basis, as they pass through a microfluidic channel. The proposed technique has been implemented with inexpensive off‐the‐shelf components like laser diode, photo‐detector and a micro‐controller. The ability of the optofluidic flow analyzer to asses about 308,049 cells within 3 minutes has been demonstrated. The presented technique is capable of detecting very low parasitemia levels with high sensitivity.
2.
The membrane spanning domain (MSD) of human immunodeficiency virus 1 (HIV-1) envelope glycoprotein gp41 is important for fusion and infection. We used molecular dynamics (MD) simulations (3.4 μs total) to relate membrane and peptide properties that lead to water solvation of the α-helical gp41 MSD's midspan arginine in pure dipalmitoylphosphatidylcholine (DPPC) and in 50/50 DPPC/cholesterol membranes. We find that the midspan arginine is solvated by water that penetrates the inner leaflet, leading to a so-called water defect. The water defect is surprisingly robust across initial conditions and membrane compositions, but the presence of cholesterol modulates its behavior in several key ways. In the cholesterol-containing membranes, fluctuations in membrane thickness and water penetration depth are localized near the midspan arginine, and the MSD helices display a tightly regulated tilt angle. In the cholesterol-free membranes, thickness fluctuations are not as strongly correlated to the peptide position and tilt angles vary significantly depending on protein position relative to boundaries between domains of differing thickness. Cholesterol in an HIV-1 viral membrane is required for infection. Therefore, this work suggests that the colocalized water defect and membrane thickness fluctuations in cholesterol-containing viral membranes play an important role in fusion by bringing the membrane closer to a stability limit that must be crossed for fusion to occur. 相似文献
3.
Ramesh Gannu Chinna Reddy Palem Shravan Kumar Yamsani Vamshi Vishnu Yamsani Madhusudan Rao Yamsani 《AAPS PharmSciTech》2010,11(2):976-985
The purpose of the present study was to develop and optimize reservoir-based transdermal therapeutic system (TTS) for buspirone
(BUSP), a low bioavailable drug. A three-factor, three-level Box–Behnken design was employed to optimize the TTS. Hydroxypropyl
methylcellulose, d-limonene and propylene glycol were varied as independent variables; cumulative amount permeated across rat abdominal skin
in 24 h, flux and lag time were selected as dependent variables. Mathematical equations and response surface plots were used
to relate the dependent and independent variables. The statistical validity of polynomials was established, and optimized
formulation factors were selected by feasibility and grid search. Validation of the optimization study with seven confirmatory
runs indicated high degree of prognostic ability of response surface methodology. BUSP-OPT (optimized formulation) showed
a flux 104.6 μg cm−2 h−1, which could meet target flux. The bioavailability studies in rabbits showed that about 2.65 times improvement (p < 0.05) in bioavailability, after transdermal administration of BUSP-OPT compared to oral solution. The ex vivo–in vivo correlation was found to have biphasic pattern and followed type A correlation. Reservoir-based TTS for BUSP was developed
and optimized using Box–Behnken statistical design and could provide an effective treatment in the management of anxiety. 相似文献
4.
Tannu NS Wu J Rao VK Gadgil HS Pabst MJ Gerling IC Raghow R 《Analytical biochemistry》2004,327(2):222-232
We compared trysin-digested protein samples desalted by ZipTip(C18) reverse-phase microcolumns with on-plate washing of peptides deposited either on paraffin-coated plates (PCP), Teflon-based AnchorChip plates, or stainless steel plates, before analysis by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). Trypsinized bovine serum albumin and ovalbumin and 16 protein spots extracted from silver-stained two-dimensional gels of murine C(2)C(12) myoblasts or human leukocytes, prepared by the above two methods, were subjected to MALDI on PCP, AnchorChip plates, or uncoated stainless steel plates. Although most peptide mass peaks were identical regardless of the method of desalting and concentrating of protein samples, samples washed and concentrated by the PCP-based method had peptide peaks that were not seen in the samples prepared using the ZipTip(C18) columns. The mass spectra of peptides desalted and washed on uncoated stainless steel MALDI plates were consistently inferior due to loss of peptides. Some peptides of large molecular masses were apparently lost from samples desalted by ZipTip(C18) microcolumns, thus diminishing the quality of the fingerprint needed for protein identification. We demonstrate that the method of washing of protein samples on paraffin-coated plates provides an easy, reproducible, inexpensive, and high-throughput alternative to ZipTip(C18)-based purification of protein prior to MALDI-TOF-MS analysis. 相似文献
5.
Sudhakar Mokenapelli Gutam Madhu Yerrabelli Jayaprakash Rao Irlapati Vamshi Krishna Gorityala Neelima Sagurthi Someswar Rao Chitneni Prasad Rao 《Russian Journal of Bioorganic Chemistry》2020,46(5):845-855
Russian Journal of Bioorganic Chemistry - A new series of 2,5-regioselective benzofuran-tetrazole hybrids (XIIIa–XIIIp) were synthesised from 2H-chromene-3-carbonitriles (IXa), (IXb) in multi... 相似文献
6.
Jitendra A. Sattigeri Sachin Sethi Joseph A. Davis Shahadat Ahmed Geeta V. Rayasam Balasaheb G. Jadhav Satya M. Chilla Dhrubajyoti Datta A. Gadhave Vamshi K. Tulasi Tarun Jain Sreedhara Voleti Biju Benjamin Sunitha Udupa Garima Jain Yogender Singh Kona Srinivas Vinay S. Bansal Ian A. Cliffe 《Bioorganic & medicinal chemistry letters》2017,27(11):2313-2318
Designing drug candidates exhibiting polypharmacology is one of the strategies adopted by medicinal chemists to address multifactorial diseases. Metabolic disease is one such multifactorial disorder characterized by hyperglycaemia, hypertension and dyslipidaemia among others. In this paper we report a new class of molecular framework combining the pharmacophoric features of DPP4 inhibitors with those of ACE inhibitors to afford potent dual inhibitors of DPP4 and ACE. 相似文献
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8.
Spinal muscular atrophy (SMA) is caused by low survival motor neuron (SMN) levels and patients represent a clinical spectrum due primarily to varying copies of the survival motor neuron-2 (SMN2) gene. Patient and animals studies show that disease severity is abrogated as SMN levels increase. Since therapies currently being pursued target the induction of SMN, it will be important to understand the dosage, timing and cellular requirements of SMN for disease etiology and potential therapeutic intervention. This requires new mouse models that can induce SMN temporally and/or spatially. Here we describe the generation of two hypomorphic Smn alleles, Smn(C-T-Neo) and Smn(2B-Neo). These alleles mimic SMN2 exon 7 splicing, titre Smn levels and are inducible. They were specifically designed so that up to three independent lines of mice could be generated, herein we describe two. In a homozygous state each allele results in embryonic lethality. Analysis of these mutants indicates that greater than 5% of Smn protein is required for normal development. The severe hypomorphic nature of these alleles is caused by inclusion of a loxP-flanked neomycin gene selection cassette in Smn intron 7, which can be removed with Cre recombinase. In vitro and in vivo experiments demonstrate these as inducible Smn alleles. When combined with an inducible Cre mouse, embryonic lethality caused by low Smn levels can be rescued early in gestation but not late. This provides direct genetic evidence that a therapeutic window for SMN inductive therapies may exist. Importantly, these lines fill a void for inducible Smn alleles. They also provide a base from which to generate a large repertoire of SMA models of varying disease severities when combined with other Smn alleles or SMN2-containing mice. 相似文献
9.
Werner J. Geldenhuys Vamshi K. Manda Rajendar K. Mittapalli Cornelis J. Van der Schyf Peter A. Crooks Linda P. Dwoskin David D. Allen Paul R. Lockman 《Bioorganic & medicinal chemistry letters》2010,20(3):870-877
A set of semi-rigid cyclic and acyclic bis-quaternary ammonium analogs, which were part of a drug discovery program aimed at identifying antagonists at neuronal nicotinic acetylcholine receptors, were investigated to determine structural requirements for affinity at the blood–brain barrier choline transporter (BBB CHT). This transporter may have utility as a drug delivery vector for cationic molecules to access the central nervous system. In the current study, a virtual screening model was developed to aid in rational drug design/ADME of cationic nicotinic antagonists as BBB CHT ligands. Four 3D-QSAR comparative molecular field analysis (CoMFA) models were built which could predict the BBB CHT affinity for a test set with an r2 <0.5 and cross-validated q2 of 0.60, suggesting good predictive capability for these models. These models will allow the rapid in silico screening of binding affinity at the BBB CHT of both known nicotinic receptor antagonists and virtual compound libraries with the goal of informing the design of brain bioavailable quaternary ammonium analogs that are high affinity selective nicotinic receptor antagonists. 相似文献
10.
Rajeev Kapila Suman Kapila Meena Kapasiya Divya Pandey Ajay Dang Vamshi Saliganti 《Probiotics and antimicrobial proteins》2012,4(3):173-179
Six strains of lactobacilli belonging to three species (Lactobacillus casei, Lactobacillus acidophilus and Lactobacillus helveticus) were evaluated for probiotic attributes viz. acid tolerance, bile tolerance and cell surface hydrophobicity. All the six strains exhibited probiotic attributes with considerable degree of variation. Three Lactobacillus strains selected on the basis of probiotic attributes were used for preparing three different fermented milks. In order to evaluate the effect of feeding these probiotic fermented milks on macrophage cell function, an in-vivo trial was conducted in mice for a period of 2, 5 and 8?days. The control group of mice was fed with skim milk. The phagocytic activity of macrophages increased significantly (P?<?0.05) on feeding fermented milk prepared using L. acidophilus, L. casei and L. helveticus as compared to milk group (control) on 2nd, 5th and 8th day of feeding, respectively. Likewise, the release of ??-glucuronidase and ??-galactosidase from peritoneal macrophages increased significantly (P?<?0.05) on 2nd, 5th and 8th day of feeding as compared to their respective control group (milk). The results thus depict that feeding of probiotic fermented milk enhances phagocytic activity of the macrophages. 相似文献