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The purpose of this study was to analyse whether costochondral grafts (CCG) fulfil temporomandibular joint (TMJ) reconstructive goals in children with TMJ ankylosis. A total of 23 patients (12 male, 11 female, aged 3-16 years) with unilateral or bilateral TMJ ankylosis operated on between January 2014 to April 2018 were included in the study. Maximal incisal opening (MIO), frequency of reankylosis, and growth of CCG, were evaluated at one month and six months for one year, and after that once yearly. Mouth opening changes with time were assessed by the Friedman test and growth was compared at follow up and analysed using the paired t test. Mean (range) follow up was 18 (12-48) months. Study results revealed follow up MIO at 12 months was highly significant (p=0.001). Out of 27 CCG studied, only one graft had undergone re-ankylosis. Based on the predetermined criteria using condylion to gnathion (Co-Gn) measurement in the posteroanterior cephalogram, CCG were categorised into optimum, sub-optimum, and overgrowth. However, long-standing TMJ ankylosis cases still displayed mandibular asymmetry at the end of the study, even with "optimal growth" radiographically. Overall comparison between the immediate postoperative and last follow up Co-Gn measurements in either unilateral or bilateral cases was not significant. CCG with functional matrix maintained the growth of the mandible and MIO in TMJ ankylosis. It can be concluded that CCG partially fulfils reconstructive goals; however, patients need to be followed up till the end of puberty for a substantive conclusion.
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Anquilosis , Trastornos de la Articulación Temporomandibular , Adolescente , Anquilosis/cirugía , Artroplastia , Niño , Preescolar , Femenino , Objetivos , Humanos , Masculino , Articulación Temporomandibular/diagnóstico por imagen , Articulación Temporomandibular/cirugía , Trastornos de la Articulación Temporomandibular/cirugíaRESUMEN
Subcondylar fracture of the mandible accounts for 25-35% of all mandibular fractures. In the past, most subcondylar fractures were managed non-surgically. The traditional method of fixation for subcondylar fractures uses two miniplates; however some bench studies have reported that trapezoidal plates are superior. The aim of this study was to compare the outcomes of subcondylar fractures fixed either with two non-parallel straight miniplates or with one trapezoidal plate. A randomized clinical trial was designed and implemented. Fifty-two consecutive patients with subcondylar fractures were recruited. All patients underwent surgery via a retromandibular approach. The time taken for fixation of the plate after fracture reduction and postoperative outcomes and complications were compared between the groups. The trapezoidal plates were superior in terms of ease of adaptation and time taken for fixation (P= 0.0001). Plate fracture was observed only in the two miniplates group, in four (16%) patients. Outcomes were similar in the two groups in terms of occlusion, mouth opening, protrusion, and lateral excursion. In conclusion, both systems - two miniplates and the trapezoidal plate - provide functionally stable fixation. The outcome was significantly better for the trapezoidal plate than for two miniplates regarding the time taken for insertion and ease of adaptation, but not for other parameters.
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Placas Óseas , Fracturas Mandibulares , Fijación Interna de Fracturas , Humanos , Mandíbula , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/cirugía , Fracturas Mandibulares/diagnóstico por imagen , Fracturas Mandibulares/cirugíaAsunto(s)
Estrógenos/administración & dosificación , Etinilestradiol/administración & dosificación , Etinilestradiol/efectos adversos , Melanoma/inducido químicamente , Neoplasias Cutáneas/inducido químicamente , Adolescente , Adulto , Anticonceptivos Orales , Relación Dosis-Respuesta a Droga , Estrógenos/efectos adversos , Femenino , Humanos , Medio Oeste de Estados Unidos , Estudios Retrospectivos , Adulto JovenRESUMEN
An NAD+-dependent enzymatic sensor with biofuel cell power source system for non-invasive monitoring of lactate in sweat was designed, developed, and tested. The sensor component, based on lactate dehydrogenase, showed linear current response with increasing lactate concentrations with limits of detection from 5 to 100 mM lactate and sensitivity of 0.2 µA.mM-1 in the presence of target analyte. In addition to the sensor patch a power source was also designed, developed and tested. The power source was a biofuel cell designed to oxidize glucose via glucose oxidase. The biofuel cell showed excellent performance, achieving over 80 mA at 0.4 V (16 mW) in a footprint of 3.5 × 3.5 × 0.7 cm. Furthermore, in order to couple the sensor to the power source, system electronic components were designed and fabricated. These consisted of an energy harvester (EH) and a micropotentiostat (MP). The EH was employed for harvesting power provided by the biofuel cell as well as up-converting the voltage to 3.0 V needed for the operation of the MP. The sensor was attached to MP for chronoamperometric detection of lactate. The Sensor Patch System was demonstrated under laboratory conditions.
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This multicenter single-arm phase II study evaluated the addition of pazopanib to concurrent weekly paclitaxel following doxorubicin and cyclophosphamide as neoadjuvant therapy in human epidermal growth factor receptor (HER2)-negative locally advanced breast cancer (LABC). Patients with HER2-negative stage III breast cancer were treated with doxorubicin 60 mg/m(2) and cyclophosphamide 600 mg/m(2) for four cycles every 3 weeks followed by weekly paclitaxel 80 mg/m(2) on days 1, 8, and 15 every 28 days for four cycles concurrently with pazopanib 800 mg orally daily prior to surgery. Post-operatively, pazopanib was given daily for 6 months. The primary endpoint was pathologic complete response (pCR) in the breast and lymph nodes. Between July 2009 and March 2011, 101 patients with stage IIIA-C HER2-negative breast cancer were enrolled. The pCR rate in evaluable patients who initiated paclitaxel and pazopanib was 17 % (16/93). The pCR rate was 9 % (6/67) in hormone receptor-positive tumors and 38 % (10/26) in triple-negative tumors. Pre-operative pazopanib was completed in only 39 % of patients. The most frequent grade 3 and 4 adverse events during paclitaxel and pazopanib were neutropenia (27 %), diarrhea (5 %), ALT and AST elevations (each 5 %), and hypertension (5 %). Although the pCR rate of paclitaxel and pazopanib following AC chemotherapy given as neoadjuvant therapy in women with LABC met the pre-specified criteria for activity, there was substantial toxicity, which led to a high discontinuation rate of pazopanib. The combination does not appear to warrant further evaluation in the neoadjuvant setting for breast cancer.
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Neoplasias de la Mama/tratamiento farmacológico , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Paclitaxel/administración & dosificación , Pirimidinas/administración & dosificación , Sulfonamidas/administración & dosificación , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama/patología , Ciclofosfamida/efectos adversos , Doxorrubicina/efectos adversos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Femenino , Fluorouracilo/administración & dosificación , Humanos , Indazoles , Ganglios Linfáticos/efectos de los fármacos , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Paclitaxel/efectos adversos , Pirimidinas/efectos adversos , Receptor ErbB-2/genética , Sulfonamidas/efectos adversosRESUMEN
OBJECTIVE: To compare and contrast three databases, that is, The International Centre for Nephrogenic Systemic Fibrosis Registry (ICNSFR), the Food and Drug Administration Adverse Event Reporting System (FAERS) and a legal data set, through pharmacovigilance and to evaluate international nephrogenic systemic fibrosis (NSF) safety efforts. METHODS: The Research on Adverse Drug events And Reports methodology was used for assessment-the FAERS (through June 2009), ICNSFR and the legal data set (January 2002 to December 2010). Safety information was obtained from the European Medicines Agency, the Danish Medicine Agency and the Food and Drug Administration. RESULTS: The FAERS encompassed the largest number (n = 1395) of NSF reports. The ICNSFR contained the most complete (n = 335, 100%) histopathological data. A total of 382 individual biopsy-proven, product-specific NSF cases were analysed from the legal data set. 76.2% (291/382) identified exposure to gadodiamide, of which 67.7% (197/291) were unconfounded. Additionally, 40.1% (153/382) of cases involved gadopentetate dimeglumine, of which 48.4% (74/153) were unconfounded, while gadoversetamide was identified in 7.3% (28/382) of which 28.6% (8/28) were unconfounded. Some cases involved gadobenate dimeglumine or gadoteridol, 5.8% (22/382), all of which were confounded. The mean number of exposures to gadolinium-based contrast agents (GBCAs) was gadodiamide (3), gadopentetate dimeglumine (5) and gadoversetamide (2). Of the 279 unconfounded cases, all involved a linear-structured GBCA. 205 (73.5%) were a non-ionic GBCA while 74 (26.5%) were an ionic GBCA. CONCLUSION: Clinical and legal databases exhibit unique characteristics that prove complementary in safety evaluations. Use of the legal data set allowed the identification of the most commonly implicated GBCA. ADVANCES IN KNOWLEDGE: This article is the first to demonstrate explicitly the utility of a legal data set to pharmacovigilance research.
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Medios de Contraste/efectos adversos , Gadolinio/efectos adversos , Dermopatía Fibrosante Nefrogénica/inducido químicamente , Farmacovigilancia , Conducta Cooperativa , Bases de Datos Factuales , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Gadolinio DTPA/efectos adversos , Compuestos Heterocíclicos , Humanos , Masculino , Meglumina/efectos adversos , Meglumina/análogos & derivados , Compuestos Organometálicos/efectos adversos , Sistema de Registros , Estados UnidosRESUMEN
Moth bean (Vigna aconitifolia (Jacq.) Marechal), an important grain-legume crop grown in hot desert regions of Thar, under scorching sun rays, was investigated for heat tolerance at molecular level. In the present study, we constructed a forward suppression subtractive hybridization (SSH) cDNA library of heat tolerant genotype RMO-40 to identify genes expressing under delayed response to elevated temperature. Heat induction was carried out by exposing 14-day-old seedlings to elevated temperature of 42 °C for 30 min. A total of 125 unigenes (33 contigs and 92 singletons) were derived by cluster assembly and sequence alignment of 200 ESTs; out of 125 unigenes, 21 (16 %) were found to be novel to moth bean. Gene ontology functional classification terms were retrieved for 98 (78.4 %) unigenes of which 73 (58.4 %) ESTs were functionally annotated (GO consensus) where 19 unigenes were annotated with 11 enzyme commission (EC) codes and were mapped to 25 different KEGG pathways. We have identified a majority of heat-shock proteins (constituting 35 % of the present library) aiding heat stress tolerance to moth bean. An expression level of 22 ESTs generated from the above SSH cDNA library was studied through semiquantitative RT-PCR assay simultaneously under 5 and 30 min of heat stress at 42 °C.
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Etiquetas de Secuencia Expresada , Fabaceae/genética , Proteínas de Plantas/genética , Sequías , Fabaceae/fisiología , Regulación de la Expresión Génica de las Plantas , Biblioteca de Genes , Calor , Proteínas de Plantas/metabolismo , Estrés Fisiológico , Técnicas de Hibridación SustractivaRESUMEN
Liquid chromatographic method was developed for simultaneous quantitative determination of dicyclomine hydrochloride, mefenamic acid and paracetamol in their combined dosage form. The separation was achieved using a C18 column (250×4.6 mm id, 5 µm) using acetonitrile:20 mM potassium dihydrogen phosphate 70:30 (v/v) adjusted to pH 4 using orthophosphoric acid as mobile phase at a flow rate of 1 ml/min and detection at 220 nm. Separation was completed within 12 min. The retention times of dicyclomine hydrochloride, mefenamic acid and paracetamol were 3.8, 9.3 and 2.5 minutes respectively. The proposed method was found to have linearity in concentration range of 10-100 µg/ml for dicyclomine hydrochloride, 0.05-10 µg/ml for mefenamic acid and 0.1-20 µg/ml for paracetamol. The developed method has been statistically validated and was found to be simple, precise, reproducible and accurate. The developed and validated method was successfully used for the quantitative analysis of commercially available dosage form.
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Moth bean ( Vigna aconitifolia (Jacq.) Marechal) is an important grain legume crop grown in rain fed areas of hot desert regions of Thar, India, under scorching sun rays with very little supplementation of water. An SSH cDNA library was generated from leaf tissues of V. aconitifolia var. RMO-40 exposed to an elevated temperature of 42 °C for 5 min to identify early-induced genes. A total of 488 unigenes (114 contigs and 374 singletons) were derived by cluster assembly and sequence alignment of 738 ESTs; out of 206 ESTs (28%) of unknown proteins, 160 ESTs (14%) were found to be novel to moth bean. Only 578 ESTs (78%) showed significant BLASTX similarity (<1 × 10(-6)) in the NCBI non-redundant database. Gene ontology functional classification terms were retrieved for 479 (65%) sequences, and 339 sequences were annotated with 165 EC codes and mapped to 68 different KEGG pathways. Four hundred and fifty-two ESTs were further annotated with InterProScan (IPS), and no IPS was assigned to 153 ESTs. In addition, the expression level of 27 ESTs in response to heat stress was evaluated through semiquantitative RT-PCR assay. Approximately 20 different signaling genes and 16 different transcription factors have been shown to be associated with heat stress in moth bean for the first time.
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Fabaceae/genética , Regulación de la Expresión Génica de las Plantas/genética , Biblioteca de Genes , Genes de Plantas/genética , Secuencia de Bases , Cartilla de ADN/genética , Etiquetas de Secuencia Expresada , Perfilación de la Expresión Génica , Genotipo , Calor , Anotación de Secuencia Molecular , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Alineación de Secuencia , Análisis de Secuencia de ADN , Estrés FisiológicoRESUMEN
BACKGROUND: During spring of 2009, pandemic of Influenza A (H1N1) virus emerged and spread globally. We describe the clinical profile of patients who were found H1N1 Positive in Surat district from 27th June 2009 to march 2010. METHODS: Retrospective data of 824 patients from surat districts who were suspected with influenza like illness was collected They were subjected to throat swab testing for H1N1. Out of them 154 were positive for 2009 H1N1 virus with use of real time reverse transcriptase polymerase chain reaction assay. (TAQ MAN real time PCR CDC protocol). Clinical parameters of these 154 patients were analyzed. RESULTS: Out of 824 suspected H1N1, 154 (18.68%) patients were confirmed (positive) for 2009 HIN1. Maximum (70.77%) patients are in age group 14-50 years. Male [86 (55.84%)] were affected more than Females [68 (44.15%)]. 58 (37.66%) had underlying Co-Morbid condition. Fever (98.70%) and cough (94.15%) were the most common presenting symptom. Total 41 (26.62 %) patients were put on mechanical ventilator, out of them 17 (41.46%) survived. Total 24 (58.53%) patients were initially put on noninvasive (Bipap) ventilator followed by invasive Mechanical ventilator, while 9 (21.95%) patients were put on only noninvasive (Bipap) ventilator and total 8 patients were put directly on invasive Mechanical ventilator. 154 H1N1 positive patients, who underwent chest x-ray on admission 112 (72%) had findings consistent with pneumonia/ARDS. Most common site is lower zone and simultaneous involvement of both lungs is more common than single lung involvement. Out of the 154 patients, those patients who received oseltamivir within 48 hour of onset of illness all were cured. Patients who expired had received oseltamivir after 48 hrs. Our data suggests that the use of oseltamivir was beneficial in hospitalized patients even up to 72 hrs of onset of symptoms. We observed no significant side effect of oseltamivir 150 mg twice day dose for 5-7 days. We observed two peaks of H1N1 during this period, second peak was less severe than first one. CONCLUSIONS: During evaluation period, 2009 H1N1 influenza caused severe illness requiring hospitalization, including pneumonia and respiratory distress and co-morbid condition. Maximum patients were between age group of 14-50 year. Fever and cough were most common presenting symptoms. Nearly 36.36% patients had one or more underlying medical conditions. Mechanical ventilatory support had role in reduction in mortality. Patients seemed to be benefited from antiviral therapy if started within 72 hour of onset of symptom. There were no significant side effects of Oseltamivir observed in this study. Development of ARDS, requirement of Mechanical ventilation and having co-morbid condition were poor prognostic factors. We observed two peaks of H1N1 during this period second peak was less severe than first one. It may be due to development of immunity, Disease awareness, early diagnosis and treatment and health education.
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Subtipo H1N1 del Virus de la Influenza A , Gripe Humana/diagnóstico , Adolescente , Adulto , Anciano , Femenino , Humanos , Gripe Humana/terapia , Gripe Humana/virología , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Adulto JovenRESUMEN
Cardiac arrhythmias as cause of sudden cardiac death remains an important public health problem. The availability of effective treatment in terms of the implantable defibrillator makes it critical to identify individuals at risk. An essential step in this process is the use of noninvasive techniques to screen patients and identify those at risk. The detection of ventricular late potential using the SAECG as a non-invasive technique is being explored for this purpose. The objective of the study was to stratify the future cardiovascular events including life threatening cardiac arrhythmias, in different cardiac diseases through positive and negative predictive values of SAECG and comparing with EF% another mechanical determinant. The study was conducted on 152 subjects selected from the OPD and admitted case of the New Civil Hospital and Govt. Medical College, Surat; between 25 to 75 years of age group, from August 2001 to June 2004. 80 healthy subjects free from any major acute/chronic illness were selected as a control using our own normative values for SAECG. The statistical analysis was performed using SPSS package. The results obtained were analyzed for significance by using Chi square and Independent 't' test. When we compared the cardiac arrhythmic events on 6 month follow-up study, based on SAECG and EF% separately we found that negative predictive value of SAECG was more (99.1%) than negative predictive value of EF% (93.6%). However positive predictive values for cardiac arrhythmic events of SAECG were less (28.9%) compare to EF% (42.9%). When both the parameters SAECG and EF% are considered together the negative as well as positive predictive values of these tests were quite high (100% and 50% respectively). In this study conducted on 152 patients we found that SAECG and EF% together were an accurate predictor of the cardiac arrhythmic events in terms of positive and negative predictive value while SAECG or EF% alone were not. However SAECG has got a more negative predictive value compare to EF%. In this study SAECG compared favorably or even better than EF% for risk stratification. SAECG and EF% together (and not separately) may be considered as a better investigational tool to stratify future cardiovascular arrhythmic events.
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Arritmias Cardíacas/diagnóstico , Enfermedades Cardiovasculares/diagnóstico , Electrocardiografía , Sistema de Conducción Cardíaco/fisiopatología , Volumen Sistólico , Síndrome Coronario Agudo/complicaciones , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/fisiopatología , Adulto , Anciano , Arritmias Cardíacas/etiología , Arritmias Cardíacas/fisiopatología , Cardiomiopatía Dilatada/complicaciones , Cardiomiopatía Dilatada/diagnóstico , Cardiomiopatía Dilatada/fisiopatología , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/fisiopatología , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Electrocardiografía/métodos , Humanos , Hipertensión/complicaciones , Hipertensión/diagnóstico , Hipertensión/fisiopatología , India , Persona de Mediana Edad , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/fisiopatología , Valor Predictivo de las Pruebas , Pronóstico , Medición de Riesgo , Factores de Riesgo , Procesamiento de Señales Asistido por Computador , Factores de TiempoRESUMEN
A simple, specific, accurate, and precise ultra performance liquid chromatographic method was developed and validated for the estimation of venlafaxine hydrochloride in tablet dosage forms. A acquity TM BEH column having C18, 100×2.1 mm i.d. in isocratic mode, with mobile phase containing dipotassium hydrogen phosphate: Acetonitrile (30:70 v/v; pH 7.00 with dilute o-phosphoric acid) was used. The flow rate was 0.75 ml/min and effluents were monitored at 227 nm. The retention time of venlafaxine hydrochloride was 0.548 min. The method was validated for specificity, linearity, accuracy, precision, limit of quantification, limit of detection, robustness and solution stability. Limit of detection and limit of quantification for estimation of venlafaxine hydrochloride were found to be 6.11 µg/ml and 20.33 µg/ml, respectively. Recoveries of venlafaxine hydrochloride in tablet formulations were found to be in the range of 99.3-99.5%. Proposed method was successfully applied for the quantitative determination of venlafaxine hydrochloride in tablet dosage forms.
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Essential oils extracted from flower petals of palmarosa (Cymbopogon martini), evening primrose (Primula rosea), lavender (Lavandula angustifolia) and tuberose (Polianthus tuberosa) were tested for their antibacterial activities against gram-positive and gram-negative bacteria. Different concentrations of each essential oil ranging from 10-100% were tested. Both gram-positive and gram-negative bacteria were found susceptible to the studied flower essential oils. With increase in concentration of essential oil, increase in zone of inhibition was observed thus dose-dependent response was clear for each essential oil. Essential oil extracted from Cymbopogon martini showed the highest activity against both gram positive and gram negative bacteria among the tested essential oils.
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BACKGROUND: Female participants in AIDS candidate vaccine clinical trials must agree to use effective contraception to be enrolled into the studies, and for a specified period after vaccination, since the candidate vaccines' effects on the embryo or foetus are unknown. OBJECTIVES: To review data on female participants' pregnancy rates from phase I and IIA AIDS vaccine clinical trials conducted at the Kenya AIDS Vaccine Initiative (KAVI) and to discuss the challenges of contraception among female participants. DESIGN: Descriptive observational retrospective study. SETTING: KAVI clinical trial site, Kenyatta National Hospital and University of Nairobi, Kenya. SUBJECTS: Thirty nine female participants were enrolled into these trials. They received family planning counselling and were offered a choice of different contraceptive methods, as per the protocols. All contraception methods chosen by the participants were offered at the study site at no cost to the participant. RESULTS: Four women conceived during the study period when pregnancies were to be avoided. All four had opted for sexual abstinence as a contraceptive method, but reported having been coerced by their partners to have unprotected sexual intercourse. CONCLUSION: Abstinence is clearly not a reliable contraceptive option for women in developing-country settings. Effective female-controlled contraceptives, administered at the clinical trial site, may empower female participants to better control their fertility, leading to more complete clinical trial data.
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Índice de Embarazo , Sujetos de Investigación , Vacunas contra el SIDA , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Conducta Anticonceptiva , Femenino , Humanos , Kenia , Embarazo , Estudios RetrospectivosRESUMEN
A simple, specific, accurate, and precise reverse phase liquid chromatographic method was developed and validated for the estimation of risperidone in tablet dosage forms. A Phenomenex Gemini C-18, 5 mum column having 250x4.6 mm i.d. in isocratic mode, with mobile phase containing methanol: acetonitrile: 50 mM potassium dihydrogen orthophosphate (80:10:10 v/v) was used. The flow rate was 1.3 ml/min and effluents were monitored at 234 nm. Clozapine was used as an internal standard. The retention time of risperidone and clozapine were 2.5 min and 3.3 min, respectively. The method was validated for linearity, accuracy, precision, specificity, limit of quantification, limit of detection, robustness and stability. The limit of detection and limit of quantification for estimation of risperidone was found to be 500 ng/ml and 990 ng/ml, respectively. Recovery of risperidone was found to be in the range of 99.02-101.68%. Proposed method was successfully applied for the quantitative determination of risperidone in tablet formulations.
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A simple, specific, accurate and stability indicating reversed phase high performance liquid chromatographic method was developed for the simultaneous determination of atorvastatin calcium and amlodipine besylate in tablet dosage forms. A phenomenex Gemini C-18, 5 µm column having 250×4.6 mm i.d. in isocratic mode, with mobile phase containing 0.02 M potassium dihydrogen phosphate:acetonitrile:methanol (30:10:60, v/v/v) adjusted to pH 4 using ortho phosphoric acid was used. The flow rate was 1.0 ml/min and effluents were monitored at 240 nm. The retention times of atorvastatin calcium and amlodipine besylate were 11.6 min and 4.5 min, respectively. The calibration curves were linear in the concentration range of 0.08-20 µg/ml for atorvastatin calcium and 0.1-20 µg/ml for amlodipine besylate. Atorvastatin calcium and amlodipine besylate stock solutions were subjected to acid and alkali hydrolysis, chemical oxidation and dry heat degradation. The degraded product peaks were well resolved from the pure drug peak with significant difference in their retention time values. The proposed method was validated and successfully applied to the estimation of atorvastatin calcium and amlodipine besylate in combined tablet dosage forms.
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A simple, specific, accurate and stability indicating reversed phase liquid chromatographic method was developed for the determination of nebivolol hydrochloride in tablet dosage forms. A phenomenex Gemini C-18, 5 µm column having 250×4.6 mm i.d., with mobile phase containing methanol: acetonitrile: 0.02 M potassium dihydrogen phosphate (60:30:10, v/v/v; pH 4.0) was used. The retention time of nebivolol hydrochloride was 2.6 min. The linearity for nebivolol hydrochloride was in the range of 0.2-10 µg/ml. The recovery was found to be in the range of 98.68-100.86%. The detection limit and quantification limit were found to be 0.06 µg/ml and 0.2 µg/ml, respectively. Nebivolol stock solutions were subjected to acid, alkali and neutral hydrolysis, chemical oxidation and dry heat degradation. The degraded product peaks were well resolved from the pure drug peak with significant difference in their retention time values. The proposed method was validated and successfully applied to the estimation of nebivolol hydrochloride in tablet formulations.
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A simple, specific, accurate, and precise reverse phase high performance liquid chromatographic method was developed and validated for the estimation of venlafaxine hydrochloride in tablet dosage forms. A Phenomenex Gemini C-18, 5 mum column having 250 x 4.6 mm i.d. in isocratic mode, with mobile phase containing methanol: 0.05 M potassium dihydrogen orthophosphate (70:30, v/v; pH 6.2) was used. The flow rate was 1.0 ml/min and effluents were monitored at 226 nm. Carbamazepine was used as an internal standard. The retention time of venlafaxine hydrochloride and carbamazepine were 3.7 min and 5.3 min, respectively. The method was validated for specificity, linearity, accuracy, precision, limit of quantification, limit of detection, robustness and solution stability. Limit of detection and limit of quantification for estimation of venlafaxine hydrochloride were found to be 100 ng/ml and 300 ng/ml, respectively. Recoveries of venlafaxine hydrochloride in tablet formulations were found to be in the range of 99.02-101.68%. Proposed method was successfully applied for the quantitative determination of venlafaxine hydrochloride in tablet dosage forms.