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61.
Paloma Flórez Borges Pilar Pérez Lozano Encarna García Montoya Montserrat Mi?arro Josep R Ticó Enric Jo Josep M Su?e Negre 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2014,22(1)
Background
A new, simple and accurate stability-indicating reverse phase high performance liquid chromatography method was developed and validated during the early stage of drug development of an oral lyophilizate dosage form of cetirizine dihydrochloride.Methods
For RP-HPLC analysis it was used an Eclipse XDB C8 column 150 mm × 4.6 mm, 5 μm (Agilent columns, Barcelona, Spain) as the stationary phase with a mobile phase consisted of a mixture of 0.2 M K2HPO4 pH 7.00 and acetonitrile (65:35, v/v) at a flow rate of 1 mL min −1. Detection was performed at 230 nm using diode array detector. The method was validated in accordance with ICH guidelines with respect to linearity, accuracy, precision, specificity, limit of detection and quantification.Results
The method results in excellent separation between the drug substance and its stress-induced degradation products. The peak purity factor is >950 for the drug substance after all types of stress, which confirms the complete separation of the drug substance peak from its stress induced degradation products.Regression analysis showed r2 > 0.999 for cetirizine dihydrochloride in the concentration range of 650 μg mL −1 to 350 μg mL−1 for drug substance assay and a r2 > 0.999 in the concentration range of 0.25 μg mL−1 to 5 μg mL−1 for degradation products. The method presents a limit of detection of 0.056 μg mL −1 and a limit of quantification of 0.25 μg mL−1. The obtained results for precision and accuracy for drug substance and degradation products are within the specifications established for the validation of the method.Conclusions
The proposed stability-indicating method developed in the early phase of drug development proved to be a simple, sensitive, accurate, precise, reproducible and therefore useful for the following stages of the cetirizine dihydrochloride oral lyophilizate dosage form development. 相似文献62.
Synthesis of [3H], [13C3, 15N], and [14C]SCH 900567: an inhibitor of TNF‐α (tumor necrosis factor alpha) converting enzyme (TACE) 下载免费PDF全文
Sumei Ren David Hesk Paul McNamara David Koharski Scott Borges 《Journal of labelled compounds & radiopharmaceuticals》2014,57(11):632-636
SCH 900567 is a specific inhibitor of tumor necrosis factor‐alpha converting enzyme and is a potential candidate for the treatment of rheumatoid arthritis. [3H]SCH 900567 was synthesized to support the initial drug metabolism and pharmacokinetics studies. Stable isotope‐labeled [13C3, 15N]SCH 900567 was requested by the bioanalytical group as an internal standard for Liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) method development as well as by the drug metabolism and pharmacokinetics group for a potential microdose study. [13C3, 15N]SCH 900567 is synthesized via a linear sequence of seven steps from commercially available materials in 2.6% overall yield. [14C]SCH 900567 was needed for a quantitative whole body autoradiography studies and was prepared from unlabeled Active Pharmaceutical Ingredient (API) via hydrolysis of the hydantoin moiety followed by rebuilding the hydantoin ring using potassium [14C]cyanate to give the desired product in 42.8% overall yield. Activation of the hydantoin moiety of SCH 900567 to achieve hydrolysis followed by derivatization of the resulting amino acid to avoid decarboxylation during cyclization is also discussed. 相似文献
63.
Detection of anti-HTLV-I Tax antibodies in HTLV-I enzyme-linked immunosorbent assay-negative individuals 总被引:10,自引:0,他引:10
Ehrlich GD; Glaser JB; Abbott MA; Slamon DJ; Keith D; Sliwkowski M; Brandis J; Keitelman E; Teramoto Y; Papsidero L 《Blood》1989,74(3):1066-1072
The HTLV-I tax gene protein (Tax) is not packaged within the mature viral particle from which the proteins for the commercially available enzyme-linked immunosorbent assay (ELISA) are derived. Screening of 162 individuals within a cohort of white intravenous (IV) drug abusers, previously identified as having an increased incidence of HTLV-I infection, demonstrated that seven of them had antibodies to the HTLV-I Tax protein but tested negative in HTLV-I ELISAs and Western blots prepared from purified virion proteins. Three out of 35 individuals in other behaviorally defined high-risk groups also displayed this limited pattern of reactivity to HTLV-I proteins. The presence of the anti-HTLV- I p40/Tax antibodies was determined by radioimmunoprecipitation assay (RIPA), which also revealed low levels of anti-env reactivity. The specificity of the anti-p40 reactivity was confirmed on specific Tax ELISAs and Western blots prepared from recombinantly produced Tax. In vitro gene amplification by the polymerase chain reaction (PCR) was used to establish the presence of sequences homologous to HTLV-I proviral DNA in four/four of these HTLV-I ELISA negative, Tax ELISA/Tax western blot/RIPA positive individuals. These data suggest that the true incidence of HTLV-I infection within high-risk cohorts is greater than previously reported. 相似文献
64.
Estela Natacha Brandt Busanello Vannessa Gonçalves Araujo Lobato Ângela Zanatta Clarissa Günther Borges Anelise Miotti Tonin Carolina Maso Viegas Vanusa Manfredini César Augusto João Ribeiro Carmen Regla Vargas Diogo Onofre Gomes de Souza Moacir Wajner 《Cerebellum (London, England)》2014,13(6):751-759
Zellweger syndrome (ZS) and some peroxisomal diseases are severe inherited disorders mainly characterized by neurological symptoms and cerebellum abnormalities, whose pathogenesis is poorly understood. Biochemically, these diseases are mainly characterized by accumulation of pristanic acid (Prist) and other fatty acids in the brain and other tissues. In this work, we evaluated the in vitro influence of Prist on redox homeostasis by measuring lipid, protein, and DNA damage, as well as the antioxidant defenses and the activities of aconitase and α-ketoglutarate dehydrogenase in cerebellum of 30-day-old rats. The effect of Prist on DNA damage was also evaluated in blood of these animals. Some parameters were also evaluated in cerebellum from neonatal rats and in cerebellum neuronal cultures. Prist significantly increased malondialdehyde (MDA) levels and carbonyl formation and reduced sulfhydryl content and glutathione (GSH) concentrations in cerebellum of young rats. It also caused DNA strand damage in cerebellum and induced a high micronuclei frequency in blood. On the other hand, this fatty acid significantly reduced α-ketoglutarate dehydrogenase and aconitase activities in rat cerebellum. We also verified that Prist-induced increase of MDA levels was totally prevented by melatonin and attenuated by α-tocopherol but not by the nitric oxide synthase inhibitor Nω-nitro-l-arginine methyl ester, indicating the involvement of reactive oxygen species in this effect. Cerebellum from neonate rats also showed marked alterations of redox homeostasis, including an increase of MDA levels and a decrease of sulfhydryl content and GSH concentrations elicited by Prist. Finally, Prist provoked an increase of dichlorofluorescein (DCFH) oxidation in cerebellum-cultivated neurons. Our present data indicate that Prist compromises redox homeostasis in rat cerebellum and blood and inhibits critical enzymes of the citric acid cycle that are susceptible to free radical attack. The present findings may contribute to clarify the pathogenesis of the cerebellar alterations observed in patients affected by ZS and some peroxisomal disorders in which Prist is accumulated. 相似文献
65.
Ricardo Borges Viana Scott J. Dankel Jeremy P. Loenneke Paulo Gentil Carlos Alexandre Vieira Marília dos Santos Andrade Rodrigo Luiz Vancini Claudio Andre Barbosa de Lira 《Scandinavian journal of medicine & science in sports》2020,30(7):1100-1116
There are currently many different approaches to performing exergames and there is still no consensus as to whether exergames are able to reduce anxiety levels, as well as whether exergames provide greater reductions on anxiety levels when added to traditional forms of clinical interventions. Therefore, the aim of the present systematic review and meta-analysis was to access data from studies that evaluated the effects of exergames on anxiety levels in humans. PubMed, Scopus and Cochrane databases were searched up to 22 February 2019. Inclusion criteria were acute and chronic (short-term and long-term interventions) studies which evaluated the effects of exergames in anxiety levels as primary or secondary aim. Of the 1342 studies found, 17 and 10 were included in qualitative analyses and meta-analyses, respectively. The within-group analysis found that exergames (standardized mean difference [SMD]: −0.57 [95% Confidence interval (CI): −0.86 to −0.28], P < .001) and usual care (SMD: −0.21 [95% CI: −0.34 to −0.08], P = .002) resulted in significant improvements on anxiety levels. However, the between-group meta-analysis on the effects of control interventions vs exergames (SMD: 0.02 [95% CI: −0.55 to 0.60], P = .939) found no significant difference between groups in anxiety levels reductions. There was also no significant difference (SMD: −0.04 [95% CI: −0.32 to 0.25], P = .805) between usual care vs exergames plus usual care interventions in anxiety levels reductions. Although exergames demonstrated within-group improvements in anxiety levels across different clinical populations, it was not greater than the effects from non-exercise interventions. Also, given the paucity of studies, small sample sizes, different research designs, and different population investigated, the existing evidence is insufficient to support the advantages of usual care supplemented by exergame intervention over usual care standalone in anxiety levels reduction. 相似文献
66.
67.
Sara Moreira Pedro Moreira Ana S. Sousa Rita S. Guerra Cludia Afonso Alejandro Santos Nuno Borges Teresa F. Amaral Patrícia Padro 《Nutrients》2022,14(1)
Despite the well-known benefits of the Mediterranean Diet (MedDiet), data on the sodium intake is scarce. This study aimed to quantify the association between sodium excretion and the adherence to the MedDiet in the elderly. A representative sample of 1500 Portuguese adults (≥65 years) was assessed (1321 were eligible for the present analysis). A 24 h urine sample was collected and analysed for creatinine and sodium. Excessive sodium intake was defined as above 2000 mg/day. The adherence to the MedDiet was assessed by the PREDIMED. A binary logistic regression model was conducted to evaluate the association between urinary sodium excretion and the adherence to the MedDiet. Odds Ratios (OR) and respective 95% Confidence Intervals (95% CI) were calculated. Excessive sodium excretion was observed in 80.0% of men and 91.5% of women whereas a high adherence to the MedDiet was reported by 42.2% of women and 46.4% of men. After adjusting for confounders, excessive sodium excretion was associated with a high adherence to the MedDiet in men (OR = 1.94; 95% CI: 1.03–3.65) but not in women. These results show that the MedDiet can be an important source of sodium and highlight the need for implementing strategies to reduce sodium intake when following a MedDiet. 相似文献
68.
EG Burden RW Walker DJ Ferguson AMF Goubran JR Howell JB John F Khan JS McGrath JP Evans 《Annals of the Royal College of Surgeons of England》2021,103(3):173
IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery. 相似文献
69.
John Lennon Silva-Cunha Israel Leal Cavalcante Caio Csar da Silva Barros Fernanda Arago Felix Luan Borges Venturi Larissa Santos Amaral Rolim Csar Luis Porpino Santos da Silva-Júnior Emanuel Mendes Sousa ricka Janine Dantas da Silveira Michelle Agostini Mrio Jos Romanach Oslei Paes de Almeida Sílvia Ferreira de Sousa Bruno Augusto Benevenuto de Andrade 《Medicina oral, patología oral y cirugía bucal》2022,27(1):e35
70.
Jesús K. Yamamoto-Furusho Norma N. Parra-Holguín Fabin Juliao-Baos Fabin Puentes Rocio Lpez Francisco Bosques-Padilla Esther A. Torres Humberto Nieves-Jimenz Guillermo R. Veitia-Velsquez Maria L. Jara-Alba Scrates Bautista Felipe N. Piol-Jimenez Pablo Salgado-Rosado Keyla C. Villa-Ovalles Yudelka A. Abreu-Martinez Zunilda Borges Santiago Davila-Bedoya Guillermo Otoya-Moreno Beatriz Iad-Vergara 《Medicine》2022,101(3)
The aim of the present study was to describe the epidemiological and clinical characteristics of inflammatory bowel disease (IBD), including medical and surgical treatments, in several countries in Latin America and the Caribbean.IBD is recognized as a global health problem because its incidence and prevalence have increased significantly over the last few years.This multicenter retrospective cohort study included 4714 patients with IBD diagnosed from 9 countries in Latin America and the Caribbean: Colombia, Cuba, Dominican Republic, Ecuador, Mexico, Peru, Puerto Rico, Uruguay, and Venezuela.Crohn disease (CD) was more frequent in Puerto Rico (71.9%), the Dominican Republic (61.0%), and Peru (53.1%). Ulcerative colitis was more frequent in Colombia (78.6%), Venezuela (78.2%), Mexico (75.5%), Cuba (69.9%), Ecuador (64.1%), and Uruguay (60.9%). The following clinical characteristics were more frequent in the Caribbean: penetrating behavior in CD, steroid dependence, steroid resistance, intolerance to thiopurines, extraintestinal manifestations, surgeries, hospitalizations due to IBD, and family history of IBD. The factors associated with the use of biological therapy were pancolitis in ulcerative colitis, penetrating behavior in CD, steroid resistance and dependence, presence of extraintestinal manifestations, and the need for surgery.This study from Latin America and the Caribbean demonstrated the different epidemiological and clinical characteristics of IBD. 相似文献