44 research outputs found
Oxidation of aliphatic alcohols by triethylammonium chlorochromate in non-aqueous medium – A kinetic and mechanistic study
AbstractThe oxidation of some aliphatic alcohols by triethylammonium chlorochromate (TriEACC) in dimethyl sulfoxide leads to the formation of the corresponding carbonyl compounds. The reaction is first order with respect to TriEACC. The reaction exhibited Michaelis–Menten type kinetics with respect to alcohol. The reaction is catalyzed by hydrogen ions. The hydrogen-ion dependence has the form: kobs=a+b[H+]. The oxidation of [1,1-2H2] ethanol (MeCD2OH) exhibits a substantial primary kinetic isotope effect. Oxidation of aliphatic alcohol was studied in 19 different organic solvents. The solvent effect has been analysed using Kamlet’s and Swain’s multi-parametric equation. A suitable mechanism has been proposed
Synthesis, characterization and antimicrobial activity of some novel 1-amino dibenzofuran derivatives
1022-1026A series of novel 1-amino dibenzo[b,d]furan derivatives have been synthesised via 1,3-dinitrophenol with iodophenol compound. The chemical structures of the compound have been elucidated by 1H and 13C NMR. The mass of the synthesized compounds has been estimated by LCMS. The functional groups present in the title compound are revealed from FT-IR and confirmed by elemental analysis. These compounds have also been screened for in vitro antibacterial and antifungal activities
Biological evaluation of some novel chalcones and their derivatives
Chalcones, (E)-N-(4-(4,6-dichloro-1,3,5 –triazin-2-ylamino) phenyl)-3-(4 methoxy-phenyl) acrylamide 4a-c have been prepared by employing Claisen-Schmidt condensation. Further, these chalcones 4a-c on reaction with malononitrile afford cyano-pyridines 5a-c respectively. The constitution of newly synthesised compounds have been characterized on the basis of their IR, 1H and 13C NMR spectral data. These synthesized compounds have been screened for their antibacterial and larvicidal activity.
Kinetics and Mechanism of Oxidation of Aromatic Aldehydes by Imidazolium Dichromate in Aqueous Acetic Acid Medium
The kinetics of oxidation of benzaldehyde (BA) and para-substituted benzaldehydes by imidazolium dichromate (IDC) has been studied in aqueous acetic acid medium in the presence of perchloric acid. The reaction is first order each in [IDC], [Substrate] and [H+]. The reaction rates have been determined at different temperatures and the activation parameters calculated. Electron withdrawing substituents are found to increase the reaction and electron releasing substituents are found to retard the rate of the reaction and the rate data obey the Hammett relationship. The products of the oxidation are the corresponding acids. The rate decreases with the increase in the water content of the medium. A suitable mechanism is proposed
Hormone replacement therapy menopause with a better future--a survey of views on hormone replacement therapy (HRT)
Objective: To assess the views and prescribing practices of doctors regarding hormone replacement therapy (HRT).Methods: In April 1999, 103 doctors from a teaching hospital participated in a survey. Using a self-administered questionnaire, subjects were contacted at the departments of Internal Medicine, Family Medicine, Obstetrics and Gynaecology, and Orthopaedics.Results: Seventy-two percent were below 40 years of age and 67% of the respondents were male. Most doctors believed that HRT decreases the risk of subsequent osteoporosis (97%), ischaemic heart disease (77%) and depression associated with menopause (64%). Doctors generally considered menopausal symptoms (90%), premature menopause (87%), surgical menopause (85%) and osteoporotic fracture (77%) as clear indications for hormone replacement therapy. Absolute contraindications to the therapy were stated as recent breast cancer (82%) and recent endometrial cancer (84%). Among the specialities covered, there were differing views on proposed duration of HRT. It was generally believed that a pelvic examination, cervical smear and mammography were pre-requisites when initiating and monitoring HRT. Majority (69%) felt that HRT should be offered to all menopausal women, assuming no contraindications and most (73%) did discuss HRT with their patients. However, less than 10% of the menopausal patients under their care were using HRT. Those doctors not in favor of universal offering of HRT (31%) considered unreliable patient follow up to be the main reason. Females were two times more likely to discuss HRT with their patients (p = .08). Doctors who discussed HRT with their patients were four times more likely to consider HRT for themselves or their spouses (p = .13). Gynecologists were eight times more likely to prescribe HRT than non-gynecologists (p = .001).CONCLUSION: Doctors are positively disposed to the universal offering, and use of HRT. Further studies are needed to understand a possible gap between perceived and actual prescribing practice
Synthesis and anti–microbial activity of 1,2,3–triazole tethered nitroguiacol ethers
Nitro aromatic/nitrophenols have been widely distributed in nature and are mostly isolated from marine microorganisms and had shown a broad spectrum of anti–microbial activities against a wide range of microbial pathogens. The objective of the present work is to Synthesize some new 1,2,3–triazole tethered nitroguiacol ethers and evaluated of their anti–bacterial and anti–fungal activities. A focused library of 1,2,3-triazole tethered nitroguiacol ethers were prepared by employing Cu (I) catalyzed click chemistry reaction and evaluated for their antimicrobial activities by broth microdilution method. Among the tested compounds, compounds 8e, 8f, 8g, and 8i exhibited broad–spectrum activity against selected pathogenic strains, with the MIC of 8 µg/mL for gram–positive bacteria (Staphylococcus aureus), 16 µg/mL for Pseudomonas aeruginosa (gram–negative bacteria), and Candida species, respectively. Future investigations with this class of compounds may lead to the development of potential candidates for antimicrobial drug discovery.Â
Validation of the Antiproliferative Effects of Organic Extracts from the Green Husk of Juglans regia L. on PC-3 Human Prostate Cancer Cells by Assessment of Apoptosis-Related Genes
With the increased use of plant-based cancer chemotherapy, exploring the antiproliferative effects of phytochemicals for anticancer drug design has gained considerable attention worldwide. This study was undertaken to investigate the effect of walnut green husk extracts on cell proliferation and to determine the possible molecular mechanism of extract-induced cell death by quantifying the expression of Bcl-2, Bax, caspases-3, and Tp53. PC-3 human prostate cancer cells. In this study, we found that green husk extracts suppressed proliferation and induced apoptosis in a dose- and time-dependent manner by modulating expression of apoptosis-related genes. This involved DNA fragmentation (determined by TUNEL assay) and significant changes in levels of mRNA and the expression of corresponding proteins. An increase in expressions of Bax, caspase-3, and tp53 genes and their corresponding proteins was detected using real-time PCR and western blot analysis in PC-3 cells treated with the green husk organic extracts. In contrast, Bcl2 expression was downregulated after exposure to the extracts. Our data suggest the presence of bioactive compound(s) in walnut green husks that are capable of killing prostate carcinoma cells by inducing apoptosis and that the husks are a candidate source of anticancer drugs
Differential Expression Profile and Genetic Variants of MicroRNAs Sequences in Breast Cancer Patients
The technology available for cancer diagnosis and prognosis is not yet satisfactory at the molecular level, and requires further improvements. Micro RNAs (miRNAs) have been recently reported as useful biomarkers in diseases including cancer. We performed a miRNA expression profiling study using peripheral blood from breast cancer patients to detect and identify characteristic patterns. A total of 100 breast cancer patients and 89 healthy patients were recruited for miRNA genotyping and expression profiling. We found that hs-miR-196a2 in premenopausal patients, and hs-miR-499, hs-miR-146a and hs-miR-196a2 in postmenopausal patients, may discriminate breast cancer patients from healthy individuals. In addition, we found a significant association between two microRNA polymorphisms (hs-miR-196a2 and hs-miR-499) and breast cancer risk. However, no significant association between the hs-miR-146a gene and breast cancer risk was found. In summary, the study demonstrates that peripheral blood miRNAs and their expression and genotypic profiles can be developed as biomarkers for early diagnosis and prognosis of breast cancer
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
SYNTHESIS, CHARACTERIZATION AND BIOLOGICAL STUDY OF NOVEL HETEROCYCLIC COMPOUNDS
ABSTRACT A series of new 6-bromo-2, 3-dihydro-1, 3-dimethylbenzo (h) quinazoline-4-(1H)-one and 6-bromo-1-ethyl-2, 3-dihydro-3-methylbenzo (h) quinazoline-4-(1H)-one and 6-bromo-2, 3-dihydro-3-methyl-1prophylbenzo (h) quinazoline-4-(1H)-one derivatives(6a-c) were synthesized. The functional group represented in this compound was identified by FTIR analysis. In addition to this the presence of compound can also be identified from the results of Mass spectrum and 1 H NMR spectrum. The three components were undergone the biological study of antibacterial and antifungal activity