110 research outputs found
Reduction Reactions of Electrolyte Salts for Lithium Ion Batteries: LiPF6, LiBF4, LiDFOB, LiBOB, and LiTFSI
The reduction products of common lithium salts for lithium ion battery electrolytes, LiPF6, LiBF4, lithium bisoxalato borate (LiBOB), lithium difluorooxalato borate (LiDFOB), and lithium trifluorosulfonylimide (LiTFSI), have been investigated. The solution phase reduction of different lithium salts via reaction with the one electron reducing agent, lithium naphthalenide, results in near quantitative reactions. Analysis of the solution phase and head space gasses suggests that all of the reduction products are precipitated as insoluble solids. The solids obtained through reduction were analyzed with solution NMR, IR-ATR and XPS. All fluorine containing salts generate LiF upon reduction while all oxalate containing salts generate lithium oxalate. In addition, depending upon the salt other species including, LixPFyOz, LixBFy, oligomeric borates, and lithium bis[N-(trifluoromethylsulfonylimino)] trifluoromethanesulfonate are observed
ANTI FUNGAL COMPOUNDS FROM MARINE STREPTOMYCES
Objective: To identify antifungal compounds from marine Streptomyces.Methods: Strptomyces were isolated from marine soil sample by the spread plate method. From the active strain crude compounds were extracted by the solvent extraction method. Crude compounds were purified by TLC method. Then the identification of compounds done by GC-MS analysis.Results: One of the active strain was identified as Streptomyces rubralavendulae strain SU1 (HQ234765). The antifungal compounds were shown resistant to Candida albicans. The antifungal compounds were identified by GC-MS as 2-Isopropyl-5-methyl-1-heptanol and Eicosane.Conclusion: These results could support the suggestion of Streptomyces as an alternative of the host for medicinal activity for treating fungal infections.Â
THREE-DIMENSIONAL QUANTITATIVE STRUCTURE–ACTIVITY RELATIONSHIPS MODELING STUDIES OF PHYTOCHEMICALS FROM BRASSICACEAE AS POTENT INHIBITORS AGAINST TUMOR INFLAMMATION
Objective: The aim of this study was to develop a three-dimensional quantitative structure–activity relationships (3D-QSARs) model for studying theinteraction of different phytochemicals with nuclear factor kappa B (NF-ĸB) inducing kinase, a major regulator in tumor inflammation.Methods: Different phytochemicals (ligands) from Brassicaceae were selected and tested for Lipinski's rule of five and further analyzed using interaction studies (docking) to identify the binding site in the target protein. Ligands with best fit were made to pass through ADMET filter, and the nontoxic ligands were selected based on the pIC50 values.Results: The 3D-QSARs of the ligands were designed using comparative molecular field analysis, and glucoraphanin was found to be stable and fit after subjecting for molecular dynamics simulation with annealing studies.Conclusion: Thus, the model may be prospectively used in drug design to find possible inhibitors of NF-ĸB, which plays a key prominent role in cancer inflammation.Keywords: Three-dimensional quantitative structure–activity relationships, Brassica oleracea, Simulation, Annealing, Nuclear factor kappa B kinase
Citric Acid Based Pre-SEI for Improvement of Silicon Electrodes in Lithium Ion Batteries
Silicon electrodes are of interest to the lithium ion battery industry due to high gravimetric capacity (∼3580 mAh/g), natural abundance, and low toxicity. However, the process of alloying and dealloying during cell cycling, causes the silicon particles to undergo a dramatic volume change of approximately 280% which leads to electrolyte consumption, pulverization of the electrode, and poor cycling. In this study, the formation of an ex-situ artificial SEI on the silicon nanoparticles with citric acid has been investigated. Citric acid (CA) which was previously used as a binder for silicon electrodes was used to modify the surface of the nanoparticles to generate an artificial SEI, which could inhibit electrolyte decomposition on the surface of the silicon nanoparticles. The results suggest improved capacity retention of ∼60% after 50 cycles for the surface modified silicon electrodes compared to 45% with the surface unmodified electrode. Similar improvements in capacity retention are observed upon citric acid surface modification for silicon graphite composite/ LiCoO2 cells
Influence of pre-bloom sprays of benzyladenine on in vitro recovery of hybrid embryos from crosses of Thompson Seedless and 8 seeded varieties of grape (Vitis spp.)
The present investigations are part of a study to introgress downy mildew resistance in Thompson Seedless through breeding and in ovulo embryo rescue methods. The influence of sprays of benzyladenine (BA) at prebloom and bloom on the percentage of embryo recovery, germination and development of hybrid plants is described. BA gave mixed results among the 8 cross combinations. With some crosses, BA drastically improved these parameters. In almost all crosses, germination increased significantly with BA sprays. The influence on plant development and recovery depended on BA treatment and the male parent
Assessment of the scale, coverage and outcomes of the Avahan HIV prevention program for female sex workers in Tamil Nadu, India: is there evidence of an effect?
<p>Abstract</p> <p>Background</p> <p>Avahan, the India AIDS Initiative, a large-scale HIV prevention program, using peer-mediated approaches and STI services, was implemented for high-risk groups for HIV in six states in India. This paper describes the assessment of the program among female sex workers (FSWs) in the southern state of Tamil Nadu.</p> <p>Methods</p> <p>An analytical framework based on the Avahan impact evaluation design was used. Routine program monitoring data, two rounds of cross-sectional biological and behavioural surveys among FSWs in 2006 (Round 1) and 2009 (Round 2) and quality assessments of clinical services for sexually transmitted infections (STIs) were used to assess trends in coverage, condom use and prevalence of STIs, HIV and their association with program exposure. Logistic regression analysis was used to examine trends in intermediate outcomes and their associations with intervention exposure.</p> <p>Results</p> <p>The Avahan program in Tamil Nadu was scaled up and achieved monthly reported coverage of 79% within four years of implementation. The cross-sectional survey data showed an increasing proportion of FSWs being reached by Avahan, 54% in Round 1 and 86% in Round 2 [AOR=4.7;p=0.001]. Quality assessments of STI clinical services showed consistent improvement in quality scores (3.0 in 2005 to 4.5 in 2008). Condom distribution by the program rose to cover all estimated commercial sex acts. Reported consistent condom use increased between Round 1 and Round 2 with occasional (72% to 93%; AOR=5.5; p=0.001) and regular clients (68% to 89%; AOR=4.3; p=0.001) while reactive syphilis serology declined significantly (9.7% to 2.2% AOR=0.2; p=0.001). HIV prevalence remained stable at 6.1% between rounds. There was a strong association between Avahan exposure and consistent condom use with commercial clients; however no association was seen with declines in STIs.</p> <p>Conclusions</p> <p>The Avahan program in Tamil Nadu achieved high coverage of FSWs, resulting in outcomes of improved condom use, declining syphilis and stabilizing HIV prevalence. These expected outcomes following the program logic model and declining HIV prevalence among general population groups suggest potential impact of high risk group interventions on HIV epidemic in Tamil Nadu.</p
Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry
In this paper we examine the role of crystal chemistry factors in creating
conditions for formation of magnetoelectric ordering in BiFeO3. It is generally
accepted that the main reason of the ferroelectric distortion in BiFeO3 is
concerned with a stereochemical activity of the Bi lone pair. However, the lone
pair is stereochemically active in the paraelectric orthorhombic beta-phase as
well. We demonstrate that a crucial role in emerging of phase transitions of
the metal-insulator, paraelectric-ferroelectric and magnetic disorder-order
types belongs to the change of the degree of the lone pair stereochemical
activity - its consecutive increase with the temperature decrease. Using the
structural data, we calculated the sign and strength of magnetic couplings in
BiFeO3 in the range from 945 C down to 25 C and found the couplings, which
undergo the antiferromagnetic-ferromagnetic transition with the temperature
decrease and give rise to the antiferromagnetic ordering and its delay in
regard to temperature, as compared to the ferroelectric ordering. We discuss
the reasons of emerging of the spatially modulated spin structure and its
suppression by doping with La3+.Comment: 18 pages, 5 figures, 3 table
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Rapid and sustained B-cell depletion with subcutaneous ofatumumab in relapsing multiple sclerosis : APLIOS, a randomized phase-2 study
Background: Ofatumumab, the first fully human anti-CD20 monoclonal antibody, is approved in several countries for relapsing multiple sclerosis (RMS). Objective: To demonstrate the bioequivalence of ofatumumab administered by an autoinjector versus a pre-filled syringe (PFS) and to explore the effect of ofatumumab on B-cell depletion. Methods: APLIOS (NCT03560739) is a 12-week, open-label, parallel-group, phase-2 study in patients with RMS receiving subcutaneous ofatumumab 20 mg every 4 weeks (q4w) (from Week 4, after initial doses on Days 1, 7, and 14). Patients were randomized 10:10:1:1 to autoinjector or PFS in the abdomen, or autoinjector or PFS in the thigh, respectively. Bioequivalence was determined by area under the curve (AUCτ) and maximum plasma concentration (Cmax) for Weeks 8-12. B-cell depletion and safety/tolerability were assessed. Results: A total of 256 patients contributed to the bioequivalence analyses (autoinjector-abdomen, n = 128; PFS-abdomen, n = 128). Abdominal ofatumumab pharmacokinetic exposure was bioequivalent for autoinjector and PFS (geometric mean AUCτ, 487.7 vs 474.1 h × µg/mL (ratio 1.03); Cmax, 1.409 vs 1.409 µg/mL (ratio 1.00)). B-cell counts (median cells/µL) depleted rapidly in all groups from 214.0 (baseline) to 2.0 (Day 14). Ofatumumab was well tolerated. Conclusion: Ofatumumab 20 mg q4w self-administered subcutaneously via autoinjector is bioequivalent to PFS administration and provides rapid B-cell depletion
Preclinical rationale for entinostat in embryonal rhabdomyosarcoma
BACKGROUND: Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in the pediatric cancer population. Survival among metastatic RMS patients has remained dismal yet unimproved for years. We previously identified the class I-specific histone deacetylase inhibitor, entinostat (ENT), as a pharmacological agent that transcriptionally suppresses the PAX3:FOXO1 tumor-initiating fusion gene found in alveolar rhabdomyosarcoma (aRMS), and we further investigated the mechanism by which ENT suppresses PAX3:FOXO1 oncogene and demonstrated the preclinical efficacy of ENT in RMS orthotopic allograft and patient-derived xenograft (PDX) models. In this study, we investigated whether ENT also has antitumor activity in fusion-negative eRMS orthotopic allografts and PDX models either as a single agent or in combination with vincristine (VCR). METHODS: We tested the efficacy of ENT and VCR as single agents and in combination in orthotopic allograft and PDX mouse models of eRMS. We then performed CRISPR screening to identify which HDAC among the class I HDACs is responsible for tumor growth inhibition in eRMS. To analyze whether ENT treatment as a single agent or in combination with VCR induces myogenic differentiation, we performed hematoxylin and eosin (H&E) staining in tumors. RESULTS: ENT in combination with the chemotherapy VCR has synergistic antitumor activity in a subset of fusion-negative eRMS in orthotopic "allografts," although PDX mouse models were too hypersensitive to the VCR dose used to detect synergy. Mechanistic studies involving CRISPR suggest that HDAC3 inhibition is the primary mechanism of cell-autonomous cytoreduction in eRMS. Following cytoreduction in vivo, residual tumor cells in the allograft models treated with chemotherapy undergo a dramatic, entinostat-induced (70-100%) conversion to non-proliferative rhabdomyoblasts. CONCLUSION: Our results suggest that the targeting class I HDACs may provide a therapeutic benefit for selected patients with eRMS. ENT's preclinical in vivo efficacy makes ENT a rational drug candidate in a phase II clinical trial for eRMS
Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)
Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic
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