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1.
Int J Biometeorol ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809299

RESUMO

Rapid urbanization increases urban air temperature, considerably affecting health, comfort, and the quality of life in urban spaces. The accurate assessment of outdoor thermal comfort is crucial for urban health. In the present study, a high-resolution mesoscale model coupled with a layer Urban Canopy Model (WRF-UCM) is implemented over the city of Hyderabad (17.3850° N, 78.4867° E) to simulate urban meteorological conditions during the summer and winter period of 2009 and 2019. The universal thermal climate index (UTCI) has been estimated using the model-derived atmospheric variables and a human biometeorology parameter to assess the linkages between the outdoor environment and thermal comfort. Results revealed that during summer, the city experiences nearly 50 h of very strong thermal stress, whereas about 120 h of slight cold stress are experienced during winter. The urban area in Hyderabad expanded from 5 to 15% during the study period, leading to a 2.5℃ (2.8 ℃) increase in land surface temperature, and a 1.2 (1.9 ℃) rise in air temperature at 2 m height and 1.5 (2.5 ℃) UTCI during summer (winter) time. The analysis reveals that the maximum UTCI values were noticed over built-up areas compared to other land classes during daytime and nighttime. The results derived from the present study have shown that the performance of WRF-UCM-derived UTCI reasonably portrayed the significant impact of urbanization on thermal comfort over the city and provided useful insights with regard to urban comfort and welfare.

2.
Environ Monit Assess ; 196(5): 473, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662282

RESUMO

Aerosol optical depth (AOD) serves as a crucial indicator for assessing regional air quality. To address regional and urban pollution issues, there is a requirement for high-resolution AOD products, as the existing data is of very coarse resolution. To address this issue, we retrieved high-resolution AOD over Kanpur (26.4499°N, 80.3319°E), located in the Indo-Gangetic Plain (IGP) region using Landsat 8 imageries and implemented the algorithm SEMARA, which combines SARA (Simplified Aerosol Retrieval Algorithm) and SREM (Simplified and Robust Surface Reflectance Estimation). Our approach leveraged the green band of the Landsat 8, resulting in an impressive spatial resolution of 30 m of AOD and rigorously validated with available AERONET observations. The retrieved AOD is in good agreement with high correlation coefficients (r) of 0.997, a low root mean squared error of 0.035, and root mean bias of - 4.91%. We evaluated the retrieved AOD with downscaled MODIS (MCD19A2) AOD products across various land classes for cropped and harvested period of agriculture cycle over the study region. It is noticed that over the built-up region of Kanpur, the SEMARA algorithm exhibits a stronger correlation with the MODIS AOD product compared to vegetation, barren areas and water bodies. The SEMARA approach proved to be more effective for AOD retrieval over the barren and built-up land categories for harvested period compared with the cropping period. This study offers a first comparative examination of SEMARA-retrieved high-resolution AOD and MODIS AOD product over a station of IGP.


Assuntos
Aerossóis , Poluentes Atmosféricos , Cidades , Monitoramento Ambiental , Imagens de Satélites , Índia , Monitoramento Ambiental/métodos , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Algoritmos
3.
J Contam Hydrol ; 238: 103760, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33445121

RESUMO

Groundwater in the coastal districts of West Bengal, India is highly susceptible to various factors such as over-pumping, variations in rainfall, lower elevation and risk due to sea level rise. In addition to these factors, tropical cyclone induced storm surge and saltwater intrusion also induce potential risks to the quality of the coastal aquifers. There are several knowledge gaps, as many of these factors have not previously been systematically and rigorously analysed; furthermore, up-to-date information is either unavailable or insufficient. Accordingly, the present study analysed the groundwater vulnerability during the pre- and post-monsoon months for the period from 2001 to 2010 at three main coastal districts of West Bengal: East Midnapore, South 24 Parganas and North 24 Parganas (administrative regions). The GALDIT index-based model was employed to assess salt-water intrusion into the groundwater using Geographic Information System (GIS). Spatial distribution maps were also generated to identify highly vulnerable groundwater locations. Map removal and single parameter sensitivity analyses were performed to understand the sensitivity of the parameters. The study reveals that the depth of ground-water levels for the three districts increased and also the rainfall exerts a significant effect on the groundwater depth. The chemical constituents TDS and chloride contents in groundwater during the period 2004 to 2010 were analysed. The average TDS range values for pre- and post-monsoon seasons were observed to vary in the range between 100 and 3874 mg/l and 83-1929 mg/l respectively. Reports indicate that, groundwater in the area is highly saturated with iron containing minerals like Fe(OH)3, goethite, and hematite and is also moderately saturated with the calcite, chalcedony, dolomite and quartz, whereas under-saturated with anhydrite and gypsum. The implications of the research points to the urgent need for remedial action and appropriate responses at policy-level to protect groundwater.


Assuntos
Sistemas de Informação Geográfica , Água Subterrânea , Monitoramento Ambiental , Índia , Tecnologia de Sensoriamento Remoto
4.
Environ Monit Assess ; 191(Suppl 3): 789, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31989283

RESUMO

Industrial and economic development along with the rapid growth in urban population over the global cities is generating a warmer inner core in comparison to the surrounding natural landscape, the common feature of the phenomena of urban heat island (UHI). In the earlier part of the study, the spatial relationship of the changes in the land cover types and land surface temperature (LST) is analysed for metropolitan cities of India during winter season using remote sensing techniques. In the present study, an attempt has been made to estimate the UHI intensities over the metropolitan cities of India during summer season. The LST estimated using the Landsat 7 ETM+ images reveals the presence of a unique form of surface UHIs in the dense built-up areas of different cities. The intensities of UHIs over these cities during summer season are noticed to be in the range of 10.5-14 °C. Delhi possesses the highest UHI intensity in the range of 13.4-14.0 °C, and Kolkata possessed the lowest UHI intensity in the range of 10.5-11.7 °C. Higher-temperature zones (hotspots) are noticed to be increasing within the built-up areas and barren lands. The temperature of hotspots for the northern cities Delhi and Jaipur is observed to be in the range of 45-50 °C and is highest among the cities under consideration. On comparison with the winter results, the LST ranges, UHI intensities and the hotspot ranges for summer season are found be noticeably higher. The LST distribution and the UHI pattern of these cities are found to different during summer season in comparison to the winter season.


Assuntos
Temperatura Alta , Urbanização , Cidades , Monitoramento Ambiental , Humanos , Índia , Estações do Ano
5.
Sci Rep ; 9(1): 19829, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882685

RESUMO

Theoretical predictability measures of turbulent atmospheric flows are essential in estimating how realistic the current storm-scale strategic forecast skill expectations are. Atmospheric predictability studies in the past have usually neglected intermittency and anisotropy, which are typical features of atmospheric flows, rendering their application to the storm-scale weather regime ineffective. Furthermore, these studies are frequently limited to second-order statistical measures, which do not contain information about the rarer, more severe, and, therefore, more important (from a forecasting and mitigation perspective) weather events. Here we overcome these rather severe limitations by proposing an analytical expression for the theoretical predictability limits of anisotropic multifractal fields based on higher-order autocorrelation functions. The predictability limits are dependent on the order of statistical moment (q) and are smaller for larger q. Since higher-order statistical measures take into account rarer events, such more extreme phenomena are less predictable. While spatial anisotropy of the fields seems to increase their predictability limits (making them larger than the commonly expected eddy turnover times), the ratio of anisotropic to isotropic predictability limits is independent of q. Our results indicate that reliable storm-scale weather forecasting with around 3 to 5 hours lead time is theoretically possible.

6.
J Food Sci Technol ; 53(1): 703-11, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26787990

RESUMO

A small, continuous power operated machine with a capacity of 132 kg/h was designed, fabricated and evaluated its performance for separation of annatto (Bixa orellana L.) seeds from freshly harvested pods. Physical and engineering parameters of annatto pods and seeds were evaluated to design a machine. The densities of pod, seed, and husk are 134.7 to 186.0 kg/m(3), 1206 to 1253.9 kg/m(3), 317 to 381.4 kg/m(3) respectively. The moisture content of seeds were in the range 18.83 - 20.1 % (db) and pod 8 to 10 % (db). Bixin content of seed was in the range 1.34 to 1.765 %. The friction angle for pod, seed, and husk lies between angle 30.15° to 35.76°. Breaking force was 98 N at a span of 14.5 mm. The machine consisted of concentric cylinders and beaters with different pitch of 40, 45 and 50 mm and a length of shaft is 800 mm. The actual machine output was observed to be 132.5 kg/h. Maximum bixin content was found to be retained at 300 rpm.

7.
Nutrition ; 31(7-8): 959-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26059368

RESUMO

OBJECTIVE: Diabetic retinopathy (DR) is a common cause of blindness. Although an association between hypovitaminosis D and type 1 diabetes is known, the association between vitamin D (VD) and type 2 diabetes (T2D) and its complications such as DR has been unclear. The aim of this study was to investigate the status of VD in T2D patients with and without DR. METHODS: A cross-sectional case-control study was conducted with 99 normal control (CN) participants and 164 patients with T2D, of which 82 had retinopathy (DR) and 82 did not (DNR). After a complete ophthalmic examination, inclusive of fundus fluorescein angiography, the clinical profile and the plasma levels of VD and calcium were analyzed. RESULTS: Although the mean plasma VD levels were significantly lower in the DNR and DR groups compared with the CN group, no significant differences were observed between the groups with diabetes. Although the mean levels of VD in all three groups were below the normal range, the prevalence of VD deficiency (VDD) was higher in the DNR and DR groups (66% and 63%) than in the CN group (45%), suggesting that the prevalence of VDD was higher in individuals with diabetes, regardless of the presence or absence of retinopathy. However, there were no group differences in the plasma levels of calcium. Additionally, VDD did not seem to be related to patient's age or body mass index, but was related to the duration of diabetes. CONCLUSION: Results from this study suggest a possible association between VDD and T2D, but not specifically with DR. Further investigations are warranted.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/metabolismo , Deficiência de Vitamina D/epidemiologia , Vitamina D/sangue , Adulto , Fatores Etários , Idoso , Índice de Massa Corporal , Cálcio/sangue , Estudos de Casos e Controles , Estudos Transversais , Retinopatia Diabética/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores de Tempo , Deficiência de Vitamina D/sangue
8.
Oncogene ; 28(33): 2925-39, 2009 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-19561645

RESUMO

After a decade of extensive work on gene knockout mouse models of cell-cycle regulators, the classical model of cell-cycle regulation was seriously challenged. Several unexpected compensatory mechanisms were uncovered among cyclins and Cdks in these studies. The most astonishing observation is that Cdk2 is dispensable for the regulation of the mitotic cell cycle with both Cdk4 and Cdk1 covering for Cdk2's functions. Similar to yeast, it was recently discovered that Cdk1 alone can drive the mammalian cell cycle, indicating that the regulation of the mammalian cell cycle is highly conserved. Nevertheless, cell-cycle-independent functions of Cdks and cyclins such as in DNA damage repair are still under investigation. Here we review the compensatory mechanisms among major cyclins and Cdks in mammalian cell-cycle regulation.


Assuntos
Ciclo Celular , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Animais , Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/fisiologia , Quinase 2 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Dano ao DNA , Humanos , Meiose , Camundongos , Camundongos Knockout , Modelos Biológicos
9.
Int J Tuberc Lung Dis ; 12(9): 1055-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18713504

RESUMO

BACKGROUND: Under the Indian Revised National TB Control Programme (RNTCP), smear-positive pulmonary tuberculosis (PTB) patients not confirmed as starting treatment are reported as 'initial defaulters'. SETTING: Twenty districts of Andhra Pradesh State, India. OBJECTIVE: To evaluate reasons for treatment non-initiation in smear-positive PTB patients diagnosed and reported as initial defaulters by the NTP. DESIGN: A cross-sectional survey conducted of all reported initial defaulters during the period July-September 2006. RESULTS: Of 1304 reported initial defaulters, 619 (47.5%) had been placed on treatment, having been incorrectly reported due to poor documentation of patients referred for treatment in the same district or whose treatment initiation was delayed until the subsequent quarter. Of the 685 (4.5% of the total diagnosed) who were confirmed initial defaulters, 350 (51%) were untraceable, 152 (22%) had died before treatment initiation, 38 (5.5%) were treated privately, 93 (13.5%) had other reasons (e.g., refusal of treatment, chronic case, etc.) and no data were available for 52 (8%). CONCLUSIONS: Nearly 5% of smear-positive PTB patients diagnosed in the study period were confirmed as not having initiated treatment under the RNCTP. Improvements in address recording may assist efforts to retrieve these patients for treatment. Additional evaluations are needed of improved counselling of TB suspects to prevent initial default, and of reasons for death before treatment initiation.


Assuntos
Cooperação do Paciente/estatística & dados numéricos , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Recusa do Paciente ao Tratamento/estatística & dados numéricos , Estudos Transversais , Pesquisa sobre Serviços de Saúde , Humanos , Índia , Programas Nacionais de Saúde/organização & administração , Programas Nacionais de Saúde/estatística & dados numéricos , Avaliação de Programas e Projetos de Saúde , Resultado do Tratamento , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/prevenção & controle
10.
Mol Vis ; 14: 593-601, 2008 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-18385795

RESUMO

PURPOSE: Activation of polyol pathway due to increased aldose reductase (ALR2) activity has been implicated in the development of diabetic complications including diabetic retinopathy (DR), a leading cause of blindness. However, the relationship between hyperglycemia-induced activation of polyol pathway in retina and DR is still uncertain. We investigated the relationship between ALR2 levels and human DR by measuring ALR2 activity and its product, sorbitol, in erythrocytes. METHODS: We enrolled 362 type 2 diabetic subjects (T2D) with and without DR and 66 normal subjects in this clinical case-control study. Clinical evaluation of DR in T2D patients was done by fundus examination. ALR2 activity and sorbitol levels along with glucose and glycosylated hemoglobin (HbA1C) levels in erythrocytes were determined. RESULTS: T2D patients with DR showed significantly higher specific activity of ALR2 as compared to T2D patients without DR. Elevated levels of sorbitol in T2D patients with DR, as compared to T2D patients without DR, corroborated the increased ALR2 activity in erythrocytes of DR patients. However, the increased ALR2 activity was not significantly associated with diabetes duration, age, and HbA1C in both the DR group and total T2D subjects. CONCLUSIONS: Levels of ALR2 activity as well as sorbitol in erythrocytes may have value as a quantitative trait to be included among other markers to establish a risk profile for development of DR.


Assuntos
Aldeído Redutase/sangue , Retinopatia Diabética/enzimologia , Eritrócitos/enzimologia , Glicemia/análise , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2 , Retinopatia Diabética/sangue , Retinopatia Diabética/patologia , Eritrócitos/metabolismo , Feminino , Fundo de Olho , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sorbitol/sangue
11.
Indian J Tuberc ; 54(4): 177-83, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18072530

RESUMO

BACKGROUND: There is paucity of information on epidemiological situation of Tuberculosis (TB) in Andhra Pradesh. The DOTS strategy under the Revised National Tuberculosis Control Programme (RNTCP) was introduced in the year 2000 to cover the entire State by 2005. OBJECTIVES: To estimate the prevalence of tuberculous infection among children 5-9 years of age and to compute the average Annual Risk of Tuberculosis Infection (ARTI) from the estimated prevalence. METHODS: A cluster-sample house-based tuberculin survey was carried out in a representative sample of children between 5-9 years of age. The clusters were selected by a two-stage sampling procedure. At first stage, five districts were selected by probability proportional to population size (PPS) method. Depending upon child population ratio, 32 clusters allocated to each district were further sub-divided into rural and urban clusters selected by simple random sampling. A total of 3636 children, irrespective of their BCG scar status, were tuberculin tested using one TU PPD RT23 with Tween 80 and the maximum transverse diameter of induration was measured about 72 hours later. RESULTS: The prevalence of infection estimated by mirror-image technique using observed mode of reactions attributable to infection with tubercle bacilli at 20mm was 9.6% (95% CI: 8.0-11.2). The ARTI was computed at 1.4% (95% CI: 1.1-1.6). CONCLUSION: Survey findings indicate a fairly high rate of transmission of tubercle bacilli.


Assuntos
Tuberculose/epidemiologia , Vacina BCG/imunologia , Criança , Pré-Escolar , Feminino , Geografia , Humanos , Índia/epidemiologia , Masculino , Fatores de Risco , Teste Tuberculínico , Tuberculose/prevenção & controle
12.
Indian J Clin Biochem ; 20(1): 123-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23105508

RESUMO

The antibody response to the 38kDa, 16kDa and Lipoarabinomannan (LAM) antigens ofMycobacterium tuberculosis was evaluated using three different ELISAs based on these antigens. The study group included tuberculosis patients (n=52), patients with HIV and TB co-infection (n=10), other chest symptomatics (n=5), HIV infected individuals (n=10), leprosy cases (n=7) and healthy controls (n=75). The results indicate that the 38kDa and LAM based ELISA for IgM/IgG has a low specificity (ranging from 69-85%) and sensitivity (ranging from 55-78%). When three ELISAs are carried out on a single patient the probability of detection of tuberculosis was significantly increased to 95.2% indicating that a single ELISA test is of low sensitivity and that a combination of ELISA's may be needed to be of any value as a diagnostic test for tuberculosis. Additionally, a western blot assay of the serum antibody response to protein fraction ofM. tuberculosis was analysed in 15 tuberculosis patients and five healthy controls. A multiple antibody response to various M.tuberculosis proteins was observed which varied from patient to patient as compared to controls who showed a single 38-39 kDa protein band positivity. These finding suggest that a western blot assay which determines the antibody response to a set of antigenic components ofM. tuberculosis could be a better serological test for the diagnosis of tuberculosis in our population.

13.
Mol Cell Biol ; 24(12): 5459-74, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15169907

RESUMO

Replicative senescence is induced by critical telomere shortening and limits the proliferation of primary cells to a finite number of divisions. To characterize the activity status of the replicative senescence program in the context of cell cycle activity, we analyzed the senescence phenotypes and signaling pathways in quiescent and growth-stimulated primary human fibroblasts in vitro and liver cells in vivo. This study shows that replicative senescence signaling operates at a low level in cells with shortened telomeres but becomes fully activated when cells are stimulated to enter the cell cycle. This study also shows that the dysfunctional telomeres and nontelomeric DNA lesions in senescent cells do not elicit a DNA damage signal unless the cells are induced to enter the cell cycle by mitogen stimulation. The amplification of senescence signaling and DNA damage responses by mitogen stimulation in cells with shortened telomeres is mediated in part through the MEK/mitogen-activated protein kinase pathway. These findings have implications for the further understanding of replicative senescence and analysis of its role in vivo.


Assuntos
Dano ao DNA , Mitógenos/farmacologia , Telômero/genética , Animais , Sequência de Bases , Ciclo Celular/efeitos dos fármacos , Divisão Celular , Células Cultivadas , Senescência Celular/genética , DNA Complementar/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , RNA/genética , Transdução de Sinais , Telomerase/deficiência , Telomerase/genética
15.
EMBO J ; 22(15): 4003-13, 2003 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12881434

RESUMO

Telomere shortening limits the regenerative capacity of primary cells in vitro by inducing cellular senescence characterized by a permanent growth arrest of cells with critically short telomeres. To test whether this in vitro model of cellular senescence applies to impaired organ regeneration induced by telomere shortening in vivo, we monitored liver regeneration after partial hepatectomy in telomerase-deficient mice. Our study shows that telomere shortening is heterogeneous at the cellular level and inhibits a subpopulation of cells with critically short telomeres from entering the cell cycle. This subpopulation of cells with impaired proliferative capacity shows senescence-associated beta-galactosidase activity, while organ regeneration is accomplished by cells with sufficient telomere reserves that are capable of additional rounds of cell division. This study provides experimental evidence for the existence of an in vivo process of cellular senescence induced by critical telomere shortening that has functional impact on organ regeneration.


Assuntos
Ciclo Celular , Regeneração , Telômero , Animais , Divisão Celular , Imuno-Histoquímica , Fígado/citologia , Fígado/ultraestrutura , Camundongos , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , RNA/genética , RNA/fisiologia , Telomerase/genética , Telomerase/fisiologia
16.
J Pharm Biomed Anal ; 31(2): 359-68, 2003 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-12609675

RESUMO

In this study, high performance liquid chromatography (HPLC) and second derivative spectrophotometry have been used and described for the simultaneous determination of montelukast and loratadine in pharmaceutical formulations. HPLC separation was achieved with a Symmetry C18 column and sodium phosphate buffer (pH adjusted to 3.7): acetonitrile (20:80, v/v) as eluent, at a flow rate of 1.0 ml/min. UV detection was performed at 225 nm. The LC method is simple, rapid, selective and stability indicating for the determination of montelukast. 5-Methyl 2-nitrophenol was used as internal standard for the purpose of quantification of both the drugs in HPLC. In the second-order derivative spectrophotometry, for the determination of loratadine the zero-crossing technique was applied at 276.1 nm, but for montelukast peak amplitude at 359.7 nm (tangent method) was used. Both methods were fully validated and a comparison was made for assay determination of selected drugs in formulations. The results confirm that the methods are highly suitable for its intended purpose.


Assuntos
Acetatos/análise , Antiasmáticos/análise , Cromatografia Líquida de Alta Pressão/métodos , Antagonistas não Sedativos dos Receptores H1 da Histamina/análise , Loratadina/análise , Preparações Farmacêuticas/química , Quinolinas/análise , Espectrofotometria Ultravioleta/métodos , Calibragem , Ciclopropanos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sulfetos
17.
J Pharm Biomed Anal ; 30(3): 695-703, 2002 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12367695

RESUMO

Two analytical methods have been developed for the determination of zafirlukast, a novel anti-asthmatic drug: high performance liquid chromatography (HPLC) and derivative spectrophotometry (DS). HPLC with ultraviolet detection at 225 nm is carried out with a Symmetry Shield RP18 column and a mobile phase constituted of acetonitrile and 0.01 M potassium dihydrogen phosphate buffer, adjusted the pH to 3.5 with 0.1 M KOH. The LC method is simple, rapid, selective and stability indicating. Indole was used as internal standard for the purpose of quantification of zafirlukast in HPLC. Spectrophotometry uses the third order derivative of the UV spectrum at 251.1 nm (deltalambda value 2.1 nm) for determination. Both methods were fully validated and a comparison was made. The results confirm that the methods are highly suitable for its intended purpose.


Assuntos
Compostos de Tosil/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Estabilidade de Medicamentos , Indóis , Fenilcarbamatos , Espectrofotometria Ultravioleta/métodos , Sulfonamidas , Compostos de Tosil/química
18.
J Pharm Biomed Anal ; 29(5): 873-80, 2002 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-12093521

RESUMO

An isocratic reversed phase liquid chromatographic (RP-LC) method has been developed and subsequently validated for the determination of rosiglitazone and its related impurities. Separation was achieved with a Symmetry C18 column and sodium phosphate buffer (pH adjusted to 6.2):acetonitrile (50:50, v/v) as eluent, at a flow rate of 1.0 ml/min. UV detection was performed at 245 nm. The method is simple, rapid, selective and stability indicating. Indole was used as internal standard for the purpose of quantification of rosiglitazone. The described method is linear over a range of 0.45-10 microg/ml for related impurities and 180-910 microg/ml for assay of rosiglitazone. The method precision for the determination of assay and related compounds was below 1.0 and 3.6% RSD, respectively. The mean recoveries of impurities were found to be in the range of 95-102%. The percentage recoveries of Active Pharmaceutical Ingredient (API) from dosage forms ranged from 99.02 to 101.30. The method is useful in the quality control of bulk manufacturing and also in pharmaceutical formulations.


Assuntos
Cromatografia Líquida/métodos , Hipoglicemiantes/análise , Preparações Farmacêuticas/química , Tiazóis/análise , Tiazolidinedionas , Padrões de Referência , Reprodutibilidade dos Testes , Rosiglitazona , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
19.
Cathet Cardiovasc Diagn ; 42(4): 437-9, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9408633

RESUMO

We report and attempt to classify a previously undescribed coronary artery anomaly. Our patient had all three coronary arteries arising from a common ostium in the right sinus of Valsalva, with an unusual distribution to the left coronary artery system: the anomalous left circumflex system taking an intraseptal (intramyocardial) course and the anomalous left anterior descending system taking an interarterial (between the great vessels) course.


Assuntos
Anomalias dos Vasos Coronários/complicações , Isquemia Miocárdica/etiologia , Seio Aórtico/anormalidades , Idoso , Angiografia Coronária , Anomalias dos Vasos Coronários/classificação , Anomalias dos Vasos Coronários/diagnóstico , Seguimentos , Humanos , Masculino , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/terapia , Ventriculografia com Radionuclídeos
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