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1.
Microb Ecol ; 86(1): 49-74, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35657425

RESUMO

Forest soils are a pressing subject of worldwide research owing to the several roles of forests such as carbon sinks. Currently, the living soil ecosystem has become dreadful as a consequence of several anthropogenic activities including climate change. Climate change continues to transform the living soil ecosystem as well as the soil microbiome of planet Earth. The majority of studies have aimed to decipher the role of forest soil bacteria and fungi to understand and predict the impact of climate change on soil microbiome community structure and their ecosystem in the environment. In forest soils, microorganisms live in diverse habitats with specific behavior, comprising bulk soil, rhizosphere, litter, and deadwood habitats, where their communities are influenced by biotic interactions and nutrient accessibility. Soil microbiome also drives multiple crucial steps in the nutrient biogeochemical cycles (carbon, nitrogen, phosphorous, and sulfur cycles). Soil microbes help in the nitrogen cycle through nitrogen fixation during the nitrogen cycle and maintain the concentration of nitrogen in the atmosphere. Soil microorganisms in forest soils respond to various effects of climate change, for instance, global warming, elevated level of CO2, drought, anthropogenic nitrogen deposition, increased precipitation, and flood. As the major burning issue of the globe, researchers are facing the major challenges to study soil microbiome. This review sheds light on the current scenario of knowledge about the effect of climate change on living soil ecosystems in various climate-sensitive soil ecosystems and the consequences for vegetation-soil-climate feedbacks.


Assuntos
Ecossistema , Microbiota , Mudança Climática , Solo/química , Florestas , Nitrogênio/análise , Microbiologia do Solo , Carbono
2.
Front Microbiol ; 13: 1069095, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36569099

RESUMO

Many filamentous fungi are known to produce several secondary metabolites or bioactive compounds during their growth and reproduction with sort of various biological activities. Genus Curvularia (Pleosporaceae) is a dematiaceous filamentous fungus that exhibits a facultative pathogenic and endophytic lifestyle. It contains ~213 species among which Curvularia lunata, C. geniculata, C. clavata, C. pallescens, and C. andropogonis are well-known. Among them, C. lunata is a major pathogenic species of various economical important crops especially cereals of tropical regions while other species like C. geniculata is of endophytic nature with numerous bioactive compounds. Curvularia species contain several diverse groups of secondary metabolites including alkaloids, terpenes, polyketides, and quinones. Which possess various biological activities including anti-cancer, anti-inflammatory, anti-microbial, anti-oxidant, and phytotoxicity. Several genes and gene factors are involved to carry and regulate the expression of these activities which are influenced by environmental signals. Some species of Curvularia also show negative impacts on humans and animals. Apart from their negative effects, there are some beneficial implications like production of enzymes of industrial value, bioherbicides, and source of nanoparticles is reported. Many researchers are working on these aspects all over the world but there is no review in literature which provides significant understanding about these all aspects. Thus, this review will provide significant information about secondary metabolic diversity, their biological activities and biotechnological implications of Curvularia species.

5.
J Pharm Biomed Anal ; 189: 113292, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32645616

RESUMO

Inorganic impurity analysis of pharmaceutical drug products is of paramount importance at trace levels due to the availability of toxic metals. The existing techniques require extensive development and chemical treatment to evaluate the presence of class I (Pb, Cd, Hg and As) and class II (Co, V and Ni) heavy metal elements which are harmful to the environment. To overcome these issues, a cost and time effective wavelength dispersive X-ray fluorescence spectrometry (XRF) was introduced to determine the concentration of trace elements in one of the angiotensin receptor blocker (ARB) (tablet sample 300 mg) according to guidelines addressed in ICH Q3D and USP. The validation study focused on class I and class II elements are also in accordance with regulatory guidelines. Overall it includes the comprehensive characterization of analytical method which is compliant with the requirement of USP. The novelty of this work includes the application of EDXRF in routine analysis of trace elements (especially volatile Hg) present in the pharmaceutical product beyond the previously published studies for the limited number of the non-pharmaceutical regime. Apart from this it also requires minimal sample preparation and method development and is able to quantify toxic impurities which are present in the sample in less than 20 ppm concentration, with the lowest level of detection up to 0.1 ppm.


Assuntos
Preparações Farmacêuticas , Oligoelementos , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Espectrometria por Raios X , Raios X
6.
J AOAC Int ; 92(2): 394-403, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19485197

RESUMO

A simple, precise, and accurate high-performance liquid chromatographic method was developed and validated to determine percent drug release of levodopa (LEV), carbidopa (CAR), and entacapone (ENT) from its combination dosage form. A mixture of acetonitrile and buffer was used as the mobile phase for reversed-phase liquid chromatographic separation for determination of the in vitro drug release of LEV, CAR, and ENT. A dissolution test was conducted at 75 rpm with United States Pharmacopeia (USP) apparatus-II (paddle) by using pH 5.5 phosphate buffer as a dissolution medium. Three formulations, differing in strength, were evaluated. The developed method was validated for specificity, linearity, precision, accuracy, and solution stability. The specificity of the method was determined in the presence of placebo interference. The method was linear over the drug concentration ranges of 4-210 microg/mL for LEV, 1-52 microg/mL for CAR, and 6-280 microg/mL for ENT. Precision was established by determination of system precision, method precision, and intermediate precision. Accuracy values for the method ranged from 96.8 to 104.3% for LEV, from 97.2 to 101.3% for CAR, and from 99.5 to 102.8% for ENT. The developed method was suitable for estimating percent drug release of LEV, CAR, and ENT in terms of the dissolution test.


Assuntos
Carbidopa/administração & dosagem , Carbidopa/análise , Catecóis/administração & dosagem , Catecóis/análise , Cromatografia Líquida de Alta Pressão/métodos , Levodopa/administração & dosagem , Levodopa/análise , Nitrilas/administração & dosagem , Nitrilas/análise , Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/análise , Antiparkinsonianos/farmacocinética , Carbidopa/farmacocinética , Catecóis/farmacocinética , Química Farmacêutica , Cromatografia Líquida de Alta Pressão/estatística & dados numéricos , Humanos , Técnicas In Vitro , Levodopa/farmacocinética , Nitrilas/farmacocinética , Reprodutibilidade dos Testes , Solubilidade , Comprimidos
7.
J AOAC Int ; 91(2): 292-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18476340

RESUMO

An accurate and reproducible liquid chromatographic assay method was developed and validated for the determination of nebivolol and valsartan in a capsule formulation. Buffer-acetonitrile (55 + 45, v/v) was used for reversed-phase liquid chromatography to determine the contents of nebivolol and valsartan in the combination-capsule dosage form. The method was validated by determining parameters such as specificity, linearity, limits of detection and quantitation, precision, accuracy, and robustness. The method was found to be specific against placebo interference. Linearity was evaluated over the concentration ranges of 2-8 micro/mL for nebivolol and 32-128 microg/mL for valsartan (the correlation coefficient was 0.9999 for both nebivolol and valsartan). Both the intraday and interday precision values of the system and the method were determined. The accuracy of the method ranged from 100.66 to 102.58% for nebivolol and from 101.17 to 101.85% for valsartan. The proposed method was found to be robust when slight but deliberate changes were made in the analytical conditions. The developed method was found suitable for the assay determination of nebivolol and valsartan in a capsule formulation.


Assuntos
Benzopiranos/análise , Cromatografia Líquida/métodos , Etanolaminas/análise , Tetrazóis/análise , Valina/análogos & derivados , Combinação de Medicamentos , Nebivolol , Reprodutibilidade dos Testes , Valina/análise , Valsartana
8.
CMAJ ; 176(10): 1460; author reply 1460, 2007 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-17485704
10.
CMAJ ; 175(4): 386, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16908906
11.
J Chromatogr A ; 1101(1-2): 153-7, 2006 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-16236291

RESUMO

A simple, fast, precise, specific and economical reverse phase liquid chromatographic method was developed for determination of nitrate (NIT) impurity from nicorandil (NIC) and its tablet dosage form. NIT is process impurity as well as a degradation product of NIC. This article is based on application of amino propyl silane (APS) column for determination of NIT in presence of NIC and various excipients using potassium nitrate as a standard. The developed method was validated for its intended use by evaluating various important parameters like linearity, accuracy, recovery and specificity. The developed method was applied to evaluate the compatibility study of NIC with various excipients by monitoring the NIT content.


Assuntos
Cromatografia Líquida/métodos , Contaminação de Medicamentos , Nicorandil/análise , Nitratos/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Comprimidos/análise
13.
J AOAC Int ; 88(4): 1142-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16152933

RESUMO

A forced degradation study was successfully applied for the development of a stability-indicating assay method for determination of rosuvastatin Ca in the presence of its degradation products. The method was developed and optimized by analyzing the forcefully degraded samples. Degradation of the drug was done at various pH values. Moreover, the drug was degraded under oxidative, photolytic, and thermal stress conditions. Mass balance between assay values of degraded samples and generated impurities was found to be satisfactory. The proposed method was able to resolve all of the possible degradation products formed during the stress study. The developed method was successfully applied for an accelerated stability study of the tablet formulation. The major impurities generated during the accelerated stability study of the tablet formulation were matches with those of the forced degradation study. The developed method was validated for determination of rosuvastatin Ca, and the method was found to be equally applicable to study the impurities formed during routine and forced degradation of rosuvastatin Ca.


Assuntos
Cromatografia Líquida/métodos , Fluorbenzenos/análise , Pirimidinas/análise , Sulfonamidas/análise , Cálcio/química , Cromatografia , Estabilidade de Medicamentos , Temperatura Alta , Ácido Clorídrico/análise , Concentração de Íons de Hidrogênio , Inibidores de Hidroximetilglutaril-CoA Redutases/análise , Luz , Oxigênio/análise , Oxigênio/química , Placebos/análise , Reprodutibilidade dos Testes , Rosuvastatina Cálcica , Hidróxido de Sódio/análise , Fatores de Tempo , Raios Ultravioleta
14.
J Am Coll Radiol ; 2(3): 232-40, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17411806

RESUMO

The authors review the role of financial accounting information from the perspective of a radiology executive. They begin by introducing the role of pro forma statements. They discuss the fundamental concepts of accounting, including the matching principle and accrual accounting. The authors then explore the use of financial accounting information in making investment decisions in diagnostic medical imaging. The paper focuses on critically evaluating the benefits and limitations of financial accounting for decision making in a radiology practice.


Assuntos
Administração Financeira/organização & administração , Radiologia/economia , Contabilidade/organização & administração , Tomada de Decisões , Humanos , Radiologia/organização & administração , Estados Unidos , Recursos Humanos
15.
J Am Coll Radiol ; 2(3): 262-70, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17411809

RESUMO

We review the core issues in managerial accounting for radiologists. We introduce the topic and then explore its application to diagnostic imaging. We define key terms such as fixed cost, variable cost, marginal cost, and marginal revenue and discuss their role in understanding the operational and financial implications for a radiology facility by using a cost-volume-profit model. Our work places particular emphasis on the role of managerial accounting in understanding service costs, as well as how it assists executive decision making.


Assuntos
Contabilidade/métodos , Custos e Análise de Custo , Administração Financeira/métodos , Radiologia/economia , Serviços Contratados/economia , Humanos , Imageamento por Ressonância Magnética/economia , Admissão e Escalonamento de Pessoal/economia , Estados Unidos
16.
J AOAC Int ; 88(6): 1661-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16526448

RESUMO

A simple, fast, specific, stability-indicating, and precise reversed-phase liquid chromatographic method was developed for the determination of Cefdinir in its different dosage forms, i.e., capsules and suspensions. The method was developed and optimized by analyzing the placebo preparation, formulations, and degraded samples of the drug substance according to the International Conference on Harmonization. The proposed method can successfully separate the drug from degradation products formed under stress conditions along with pharmaceutical ingredients such as preservatives. The developed method was used successfully to determine Cefdinir in capsules and Insta-use suspensions. The developed method was found to be linear for a concentration range of 6-14 microg/mL. Average recoveries obtained with the method were 99.3 +/- 0.4 and 99.6 +/- 0.4% for Insta-use suspensions and capsules, respectively. The method was shown to be specific, precise, and robust.


Assuntos
Anti-Infecciosos/química , Cefalosporinas/química , Técnicas de Química Analítica/métodos , Cromatografia Líquida/métodos , Cápsulas , Cefdinir , Química Farmacêutica/métodos , Cromatografia , Estabilidade de Medicamentos , Modelos Químicos , Preparações Farmacêuticas , Placebos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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