624 research outputs found
Modification of the 6-Hydroxydopamine Technique for the Correct Determination of Superoxide Dismutase
Heikkila & Cabbat (Anal. Biochem. 75, 356-362 (1976)) have proposed the autoxidation of the 6-hydroxydopamine as a method to test Superoxide dismutase activity in biological samples. This method has several advantages but in some instances leads to incorrect determinations. We present here a necessary modification of the method to avoid bias.Peer Reviewe
Cucurbit[n]uril binding of platinum anticancer complexes
The encapsulation of cisplatin by cucurbit[7]uril (Q[7]) and multinuclear platinum complexes linked via a 4,4′-dipyrazolylmethane (dpzm) ligand by Q[7] and cucurbit[8]uril (Q[8]) has been studied by NMR spectroscopy and molecular modelling. The NMR studies suggest that some cisplatin binds in the cucurbituril cavity, while cis-[PtCl(NH3)2(H2O)]+ only binds at the portals. Alternatively, the dpzm-linked multinuclear platinum complexes are quantitatively encapsulated within the cavities of both Q[7] and Q[8]. Upon encapsulation, the non-exchangeable proton resonances of the multinuclear platinum complexes show significant upfield shifts in 1H NMR spectra. The H3/H3* resonances shift upfield by 0.08 to 0.55 ppm, the H5/H5* shift by 0.9 to 1.6 ppm, while the methylene resonances shift by 0.74 to 0.88 ppm. The size of the resonance shift is dependent on the cavity size of the encapsulating cucurbituril, with Q[7] encapsulation producing larger shifts than Q[8]. The upfield shifts of the dpzm resonances observed upon cucurbituril encapsulation indicate that the Q[7] or Q[8] is positioned directly over the dpzm linking ligand. The terminal platinum groups of trans-[{PtCl(NH3)2}2μ-dpzm]2+ (di-Pt) and trans-[trans-{PtCl(NH3)2}2-trans-{Pt(dpzm)2(NH3)2}]4+ (tri-Pt) provide a barrier to the on and off movement of cucurbituril, resulting in binding kinetics that are slow on the NMR timescale for the metal complex. Although the dpzm ligand has relatively few rotamers, encapsulation by the larger Q[8] resulted in a more compact di-Pt conformation with each platinum centre retracted further into each Q[8] portal. Encapsulation of the hydrolysed forms of di-Pt and tri-Pt is considerably slower than for the corresponding Cl forms, presumably due to the high-energy cost of passing the +2 platinum centres through the cucurbituril portals. The results of this study suggest that cucurbiturils could be suitable hosts for the pharmacological delivery of multinuclear platinum complexe
Novel TOP3A Variant Associated With Mitochondrial Disease: Expanding the Clinical Spectrum of Topoisomerase III Alpha-Related Diseases
ObjectivesTopoisomerase III alpha plays a key role in the dissolution of double Holliday junctions and is required for mitochondrial DNA (mtDNA) replication and maintenance. Sequence variants in the TOP3A gene have been associated with the Bloom syndrome-like disorder and described in an adult patient with progressive external ophthalmoplegia. The purpose of this report is to expand the clinical phenotype of the TOP3A-related diseases and clarify the role of this gene in primary mitochondrial disorders.MethodsA 44-year-old woman was referred to our hospital because of exercise intolerance and creatine kinase increase. Muscle biopsy and a targeted next-generation sequencing (NGS) analysis were performed.ResultsA histopathologic assessment documented a mitochondrial myopathy, and a molecular analysis revealed a novel homozygous variant in the TOP3A gene associated with multiple mtDNA deletions.DiscussionThis case suggests that TOP3A is one of the several nuclear genes associated with mtDNA maintenance disorder and expands the spectrum of its associated phenotypes, ranging from a clinical condition defined Bloom syndrome-like disorder to canonical mitochondrial syndromes
Liver transplantation for type I and type IV glycogen storage disease
Progressive liver failure or hepatic complications of the primary disease led to orthotopic liver transplantation in eight children with glycogen storage disease over a 9-year period. One patient had glycogen storage disease (GSD) type I (von Gierke disease) and seven patients had type IV GSD (Andersen disease). As previously reported [19], a 16.5-year-old-girl with GSD type I was successfully treated in 1982 by orthotopic liver transplantation under cyclosporine and steroid immunosuppression. The metabolic consequences of the disease have been eliminated, the renal function and size have remained normal, and the patient has lived a normal young adult life. A late portal venous thrombosis was treated successfully with a distal splenorenal shunt. Orthotopic liver transplantation was performed in seven children with type N GSD who had progressive hepatic failure. Two patients died early from technical complications. The other five have no evidence of recurrent hepatic amylopectinosis after 1.1–5.8 postoperative years. They have had good physical and intellectual maturation. Amylopectin was found in many extrahepatic tissues prior to surgery, but cardiopathy and skeletal myopathy have not developed after transplantation. Postoperative heart biopsies from patients showed either minimal amylopectin deposits as long as 4.5 years following transplantation or a dramatic reduction in sequential biopsies from one patient who initially had dense myocardial deposits. Serious hepatic derangement is seen most commonly in types T and IV GSD. Liver transplantation cures the hepatic manifestations of both types. The extrahepatic deposition of abnormal glycogen appears not to be problematic in type I disease, and while potentially more threatening in type IV disease, may actually exhibit signs of regression after hepatic allografting
Competências na formação em Administração: um estudo em curso de graduação de universidade pública brasileira
Resumo
Neste estudo analisou-se como foram inseridas as competências no projeto didático-pedagógico e no processo de formação dos alunos do Curso de graduação em Administração da Universidade Federal de Juiz de Fora (UFJF), Minas Gerais. Quanto aos procedimentos metodológicos, o estudo de caso, de caráter descritivo, foi o método escolhido; entrevista, questionário e documentos (projeto didático-pedagógico do Curso e Diretrizes Curriculares Nacionais (DCNs) foram as técnicas de coleta de dados. A análise ocorreu por meio de técnicas qualitativas e quantitativas. O projeto didático-pedagógico foi analisado com o intuito de se levantarem as competências propostas pelo Curso, buscando-se verificar a sua correspondência com aquelas definidas pelo MEC nas DCNs. Posteriormente, procedeu-se à aplicação do questionário aos alunos para avaliar o processo de ensino-aprendizagem, considerando-se a formação com base em competências. A entrevista foi realizada com o diretor da Faculdade de Administração. Os resultados demonstram que, mesmo sendo percebido o desenvolvimento de competências e habilidades no Curso, este não se apresenta aderente ao modelo de formação por competências, em sua totalidade. Concluiu-se que se faz necessário um trabalho de conscientização dos docentes quanto às diretrizes de desenvolvimento de competências nos alunos do Curso, visando maior integração entre as disciplinas e alteração, em longo prazo, das metodologias de ensino-aprendizagem aplicadas.
Palavras-chave: Competências. Formação por competências. Graduação em Administração. Instituição Federal de Ensino.
Abstract
This study investigates how competencies were introduced both in the students’ learning process and in the Pedagogical Project of the Business Administration Course of the Federal University of Juiz de Fora (UFJF), in Minas Gerais State. As methodological procedures, the descriptive case study was the chosen method; interview, questionnaire and documents (the Course Pedagogical Project and the Diretrizes Curriculares Nacionais (DCNs)) were the techniques of data collection. The analysis took place through qualitative and quantitative techniques. The Course Pedagogical Project was examined in order to know the competencies proposed, seeking to verify their correspondence with the ones defined by the Education Ministry in the DCNs. A questionnaire was subsequently answered by students, which aimed to assess the teaching-learning process as far as students’ competency-based formation is concerned. The findings from the research show that despite the development of competencies and skills in the Course, it is not in fact entirely adherent to the model of competency-based learning. The conclusion is that an awareness program with professors should be conducted as to students’ competency-development guidelines, pursuing more integration among Course disciplines as well as a change, in the long term, in the teaching-learning methodologies used.
Keywords: Competencies. Students’ competency-based formation. Undergraduate Business Administration Course. Federal University
Erlotinib or gefitinib for the treatment of relapsed platinum pretreated non-small cell lung cancer and ovarian cancer: a systematic review
BACKGROUND:
Platinum-based chemotherapy is the standard of care for ovarian cancer and non-small cell lung cancer (NSCLC). However, resistance to platinum agents invariably develops. Targeted therapies, such as tyrosine kinase inhibitors (TKIs), have great potential here as they exert their anti-tumour effect via alternative mechanisms to platinum-based drugs and as such may remain unaffected by emergent resistance to platinum.
METHODS:
A systematic review was conducted to investigate whether two EGFR-TKIs, erlotinib and gefitinib, have efficacy in the platinum-resistance setting. Preclinical studies of platinum-resistant cancer cell lines, which had been subsequently treated with EGFR-TKIs, were sought to establish proof-of-concept. Clinical trials reporting administration of EGFR-TKIs to ovarian cancer and NSCLC patients relapsed after therapy with platinum drugs were investigated to determine sensitivity of these cohorts to EGFR-TKI treatment. The role of EGFR mutation, copy number and protein expression on response to EGFR-TKIs after failure of platinum chemotherapy were also investigated.
RESULTS:
Preclinical models of platinum-resistant cancer were found which display a spectrum of cross-resistance profiles to EGFR-TKIs. Sensitivity to EGFR-TKIs is dependent on the activation of the EGFR pathway or EGFR interacting proteins such as HER-2. EGFR-TKIs show favourable response rates in platinum-pretreated NSCLC, 11.14% and 15.25% for 150mg/day erlotinib and 250mg/day gefitinib, respectively. These response rates significantly improve in patients of Asian descent (28.3% and 29.17%, respectively) and patients with EGFR activation mutations (41.6% and 63.89%, respectively) or increased copy number (33.3% and 45.45%, respectively). Gefitinib significantly outperformed erlotinib and should therefore be the EGFR-TKI of choice in platinum-pretreated relapsed NSCLC. In contrast, response rates are very poor to both erlotinib and gefitinib in platinum pretreated ovarian cancer, 0-5.9% and they should not be used in this cohort of patients. Preclinical models demonstrate that, while cross resistance can occur between platinums and EGFR-TKIs, there is not a generalised cross-resistance phenotype. Erlotinib and gefitinib are suitable for the treatment of platinum-pretreated NSCLC, particularly in patients with EGFR mutations or increases in copy number. Unfortunately, the high rates of EGFR protein overexpression in ovarian cancer are not translating to a clinically useful therapeutic target for EGFR-TKIs; EGFR mutations are rare in ovarian cancer. Newer TKIs may improve response rates in these cohorts and future clinical trials need to collect tumour biopsies from all patients to ensure the success of personalised chemotherapy
Muscle pain in mitochondrial diseases: a picture from the Italian network
Muscle pain may be part of many neuromuscular disorders including myopathies, peripheral neuropathies and lower motor neuron diseases. Although it has been reported also in mitochondrial diseases (MD), no extensive studies in this group of diseases have been performed so far. We reviewed clinical data from 1398 patients affected with mitochondrial diseases listed in the database of the "Nation-wide Italian Collaborative Network of Mitochondrial Diseases", to assess muscle pain and its features. Muscle pain was present in 164 patients (11.7%). It was commonly observed in subjects with chronic progressive external ophthalmoplegia (cPEO) and with primary myopathy without cPEO, but also-although less frequently-in multisystem phenotypes such as MELAS, MERFF, Kearns Sayre syndrome, NARP, MNGIE and Leigh syndrome. Patients mainly complain of diffuse exercise-related muscle pain, but focal/multifocal and at rest myalgia were often also reported. Muscle pain was more commonly detected in patients with mitochondrial DNA mutations (67.8%) than with nuclear DNA changes (32.2%). Only 34% of the patients showed a good response to drug therapy. Interestingly, patients with nuclear DNA mutations tend to have a better therapeutic response than patients with mtDNA mutations. Muscle pain is present in a significant number of patients with MD, being one of the most common symptoms. Although patients with a myopathic phenotype are more prone to develop muscle pain, this is also observed in patients with a multi system involvement, representing an important and disabling symptom having poor response to current therapy
Primary mitochondrial myopathy: Clinical features and outcome measures in 118 cases from Italy
Objective: To determine whether a set of functional tests, clinical scales, patient-reported questionnaires, and specific biomarkers can be considered reliable outcome measures in patients with primary mitochondrial myopathy (PMM), we analyzed a cohort of Italian patients. Methods: Baseline data were collected from 118 patients with PMM, followed by centers of the Italian network for mitochondrial diseases. We used the 6-Minute Walk Test (6MWT), Timed Up-and-Go Test (x3) (3TUG), Five-Times Sit-To-Stand Test (5XSST), Timed Water Swallow Test (TWST), and Test of Masticating and Swallowing Solids (TOMASS) as functional outcome measures; the Fatigue Severity Scale and West Haven-Yale Multidimensional Pain Inventory as patient-reported outcome measures; and FGF21, GDF15, lactate, and creatine kinase (CK) as biomarkers. Results: A total of 118 PMM cases were included. Functional outcome measures (6MWT, 3TUG, 5XSST, TWST, and TOMASS) and biomarkers significantly differed from healthy reference values and controls. Moreover, functional measures correlated with patients' perceived fatigue and pain severity. Patients with either mitochondrial or nuclear DNA point mutations performed worse in functional measures than patients harboring single deletion, even if the latter had an earlier age at onset but similar disease duration. Both the biomarkers FGF21 and GDF15 were significantly higher in the patients compared with a matched control population; however, there was no relation with severity of disease. Conclusions: We characterized a large cohort of PMM by evaluating baseline mitochondrial biomarkers and functional scales that represent potential outcome measures to monitor the efficacy of treatment in clinical trials; these outcome measures will be further reinvestigated longitudinally to define the natural history of PMM
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