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1.
Med Teach ; : 1-8, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963305

RESUMO

Since 1991, there have been significant changes in medical education in Georgia. Key changes include adapting national legislation toward international standards, establishing the National Center for Education Quality Enhancement (NCEQE), which was recognized in 2018 by the World Federation for Medical Education (WFME) as an accrediting agency and opening the Association for Medical Education in Europe (AMEE) International Networking Center in 2019. Undergraduate medical education, regulated by the Ministry of Education, Science and Youth of Georgia, spans six years. MD graduates then have options for further career paths, including working as junior doctors, residency, and/or pursuing PhD research.The main challenges the country presently faces are:the need to reduce the increasing number of (mainly) private medical schools. Recent updates to the national standards for undergraduate medical education have imposed stricter accreditation requirements for MD programs, resulting in the closure of schools that fail to meet these standards;postgraduate medical education is governed by the Ministry of Internally Displaced Persons from the Occupied Territories, Labor, Health and Social Affairs of Georgia (MOH) and needs further reform due to limited and paid residency positions;continuous professional development (CPD) was optional until recently, which led to an increase in professional inaccuracy and malpractice cases. To address this, regulatory bodies, including the MOH and professional associations, are preparing the legal basis for introducing compulsory CPD.

2.
Med Teach ; : 1-9, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818632

RESUMO

BACKGROUND: It is unclear whether alternating placements during clinical clerkship, without an explicit emphasis on clinical competencies, would bring about optimal educational outcomes. METHODS: This is an explanatory sequential mixed-methods research. We enrolled a convenience sample of 41 eight-year programme medical students in Sun Yat-sen University who received alternating placements during clerkship. The effects of competence-based approach (n = 21) versus traditional approach (n = 20) to clerkship teaching were compared. In the quantitative phase, course satisfaction was measured via an online survey and academic performance was determined through final scores on summative assessment. Then, in the qualitative phase, students were invited for semi-structured interviews about their learning experiences, and the transcripts were used for thematic analysis. RESULTS: Quantitative findings showed that students in the study group rated high course satisfaction and performed significantly better in their final scores compared with those in the control group. Qualitative findings from thematic analysis showed that students were relatively neutral about their preference on placement models, but clearly perceived, capitalised, and appreciated that their competencies were being cultivated by an instructor who was regarded as a positive role model. CONCLUSION: A competence-based approach to clerkship teaching resulted in better course satisfaction and academic performance, and was perceived, capitalised, and appreciated by students.

3.
Med Teach ; : 1-13, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37909275

RESUMO

This AMEE guide discusses theoretical principles and practical strategies for health professions educators to promote impactful mentoring relationships. Traditional definitions are challenged, distinctions are made between roles such as mentor, advisor, coach and sponsor. As educational environments change and options for professional development expand, we argue that the traditional dyadic format of mentoring alone will not help mentees to maximise their professional growth. Newer formats of mentoring are discussed in detail and their advantages and disadvantages compared. We use a variety of theoretical concepts to anchor the practice of mentorship: self-focussed and other-focussed motives; psychological safety; personal interpretive framework; Daloz model for balancing support and challenge; zone of proximal development; communities of practice; and development along multiple layers of competence. Recommended strategies for effective mentoring are based on extensive review of literature, as well as combined professional mentoring experiences of the authors. We use key principles from the theories described and phases of mentoring relationships as foundations for the suggested best practices of mentorship. Finally, we emphasise the role of mentees in their own professional development and provide tips for them on seeking mentors, expanding their mentoring network and taking the lead in setting the agenda during mentoring meetings and formulating action plans for their own advancement.

4.
Int J Mol Sci ; 24(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36768578

RESUMO

Soybean is a major oil crop and is also a dominant source of nutritional protein. The 20% seed oil content (SOC) of soybean is much lower than that in most oil crops and the fatty acid composition of its native oil cannot meet the specifications for some applications in the food and industrial sectors. Considerable effort has been expended on soybean bioengineering to tailor fatty acid profiles and improve SOC. Although significant advancements have been made, such as the creation of high-oleic acid soybean oil and high-SOC soybean, those genetic modifications have some negative impacts on soybean production, for instance, impaired germination or low protein content. In this review, we focus on recent advances in the bioengineering of soybean oil and its effects on agronomic traits.


Assuntos
Glycine max , Óleo de Soja , Óleo de Soja/genética , Glycine max/genética , Sementes/genética , Ácidos Graxos , Bioengenharia
5.
J Vasc Surg ; 75(4): 1431-1436, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34718100

RESUMO

BACKGROUND: Occupational injuries and disability are a source of surgeon morbidity. The purpose of this study was to assess the physical toll of working in operating rooms by Canadian vascular surgeons. OBJECTIVE: To assess workplace musculoskeletal (MSK) complaints and challenges faced by Canadian vascular surgeons and trainees and their implications on surgical practice and occupational longevity. METHODS: An online survey was distributed to resident and surgeon members of the Canadian Society of Vascular Surgery. The survey collected data on demographics, operative volume, and work-related MSK symptoms. RESULTS: The survey was distributed to 188 surgeons and trainees. After three e-mailings, 109 surveys were returned (58% response rate). Of the responders, 87% were male, 51% were 45 years or older, and 56% had been in practice for 10 or more years. Workplace MSK symptoms were reported by 83% of the responders. The most common locations were the low back (78%), neck (74%), and shoulder (30%). Most responders (83%) believed that these symptoms were related to their operative environment. Almost half (48%) sought medical care. As a result of these MSK symptoms, 25% experience chronic pain with 8% reporting time off work as a consequence. Another 11% reported an impact on their operative performance with 14% considering early retirement. A lack of operating room system changes to prevent workplace injury and disability was noted by 85% of the responders although only 3% reported their disability to their department. CONCLUSIONS: Occupational MSK symptoms and disability are common among Canadian vascular surgeons. Further research is needed to create programs to improve surgeon morbidity.


Assuntos
Dor Musculoesquelética , Doenças Profissionais , Cirurgiões , Adulto , Canadá/epidemiologia , Ergonomia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Musculoesquelética/diagnóstico , Dor Musculoesquelética/epidemiologia , Dor Musculoesquelética/etiologia , Doenças Profissionais/diagnóstico , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Prevalência , Inquéritos e Questionários
6.
New Phytol ; 224(2): 700-711, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31400160

RESUMO

Lysophosphatidate acyltransferase (LPAAT) catalyses the second step of the Kennedy pathway for triacylglycerol (TAG) synthesis. In this study we expressed Trapaeolum majus LPAAT in Brassica napus (B. napus) cv 12075 to evaluate the effects on lipid synthesis and estimate the flux control coefficient for LPAAT. We estimated the flux control coefficient of LPAAT in a whole plant context by deriving a relationship between it and overall lipid accumulation, given that this process is a exponential. Increasing LPAAT activity resulted in greater TAG accumulation in seeds of between 25% and 29%; altered fatty acid distributions in seed lipids (particularly those of the Kennedy pathway); and a redistribution of label from 14 C-glycerol between phosphoglycerides. Greater LPAAT activity in seeds led to an increase in TAG content despite its low intrinsic flux control coefficient on account of the exponential nature of lipid accumulation that amplifies the effect of the small flux increment achieved by increasing its activity. We have also developed a novel application of metabolic control analysis likely to have broad application as it determines the in planta flux control that a single component has upon accumulation of storage products.


Assuntos
Aciltransferases/metabolismo , Brassica napus/enzimologia , Sementes/química , Triglicerídeos/metabolismo , Aciltransferases/genética , Brassica napus/metabolismo , DNA de Plantas , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Plantas Geneticamente Modificadas , Triglicerídeos/química , Tropaeolum/enzimologia , Tropaeolum/genética
7.
J Exp Bot ; 70(3): 985-994, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30371807

RESUMO

Fatty acid desaturase2 (FAD2) catalyses the conversion of oleic acid to linoleic acid and is the main determinant of the levels of essential poly-unsaturated fatty acids (PUFAs) in seed oils. The very limited number of successful examples of overexpression of FAD2 over the last two decades and a shortage of reports on co-suppression make it uncertain whether FAD2 can increase PUFAs effectively across a broad range of oil crops. In this study, strong co-suppression was observed in about 80% of over 100 transgenic lines when FAD2 was overexpressed in three oilseed crops, namely flax (Linum usitatissimum), carinata (Brassica carinata), and camelina (Camelina sativa), as well as in the model plant Arabidopsis. Further analyses of Arabidopsis transgenic lines revealed both endogenous and transgenic FAD2 gene-silencing. Thus, the commonality and potency of FAD2 co-suppression seemingly imposes an obstacle to engineering oilseed PUFA enhancement by direct FAD2 overexpression. AtFAD2, driven by the 35S promoter, also caused co-suppression in Arabidopsis roots. The FAD2 co-suppression was unstable and PUFA phenotypes of T4 lines were similar to the wild-type, further indicating that high PUFA content cannot be achieved by screening advanced generations. However, we demonstrate that the obstacle of FAD2 co-suppression can be overcome in the Arabidopsis rdr6 mutant, which is impaired in post-transcriptional gene-silencing, and that lines with high PUFA content are stable through four generations.


Assuntos
Arabidopsis/genética , Brassicaceae/genética , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Insaturados/metabolismo , Linho/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Arabidopsis/metabolismo , Brassica/genética , Brassica/metabolismo , Brassicaceae/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Linho/metabolismo , Proteínas de Plantas/metabolismo , Sementes/genética
8.
BMC Med Educ ; 19(1): 439, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775732

RESUMO

BACKGROUND: Recent studies have gone to great lengths to differentiate mentoring from teaching, tutoring, role modelling, coaching and supervision in efforts to better understand mentoring processes. This review seeks to evaluate the notion that teaching, tutoring, role modelling, coaching and supervision may in fact all be part of the mentoring process. To evaluate this theory, this review scrutinizes current literature on teaching, tutoring, role modelling, coaching and supervision to evaluate their commonalities with prevailing concepts of novice mentoring. METHODS: A three staged approach is adopted to evaluate this premise. Stage one involves four systematic reviews on one-to-one learning interactions in teaching, tutoring, role modelling, coaching and supervision within Internal Medicine, published between 1st January 2000 and 31st December 2018. Braun and Clarke's (2006) approach to thematic analysis was used to identify key elements within these approaches and facilitate comparisons between them. Stage two provides an updated view of one-to-one mentoring between a senior physician and a medical student or junior doctor to contextualise the discussion. Stage three infuses mentoring into the findings delineated in stage one. RESULTS: Seventeen thousand four hundred ninety-nine citations were reviewed, 235 full-text articles were reviewed, and 104 articles were thematically analysed. Four themes were identified - characteristics, processes, nature of relationship, and problems faced in each of the four educational roles. CONCLUSIONS: Role modelling, teaching and tutoring, coaching and supervision lie within a mentoring spectrum of increasingly structured interactions, assisted by assessments, feedback and personalised support that culminate with a mentoring approach. Still requiring validation, these findings necessitate a reconceptualization of mentoring and changes to mentor training programs and how mentoring is assessed and supported.


Assuntos
Educação Médica , Mentores , Papel Profissional , Humanos , Medicina Interna , Corpo Clínico Hospitalar , Estudantes de Medicina
9.
Epilepsy Behav ; 80: 163-172, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29414547

RESUMO

In epilepsy, individual seizures can be triggered by a variety of external and internal stimuli. One of the most common trigger factors reported by patients is stress. However prevalent, stress-related triggering of episodes seems underappreciated in epilepsy for various reasons, and its misinterpretation often leads to other diagnoses, e.g., psychogenic nonepileptic seizures (PNES) or normal reactions. This article illustrates the significant role of stress as a seizure-provoking factor by referring to nine patient narratives. From this perspective, it appears that there are characteristic patterns of stress triggering, e.g., stress-induced sleep disruption, forms of acute stress, or relaxation after stress. Sometimes seizures are mistaken as symptoms of stress. Patient narratives contain interesting clues relating reports about stress and seizure histories to different epilepsy syndromes as well as nonepileptic episodes in a way that can strongly support the diagnostic process. A narrative approach is particularly valuable in this context. Therefore, accounts of stress triggering in seizures and other episodes should not be neglected, but rather taken seriously, sought and actively explored as a crucial element when taking clinical histories in patients with episodic attacks.


Assuntos
Eletroencefalografia , Transtornos Psicofisiológicos/psicologia , Convulsões/etiologia , Estresse Psicológico/complicações , Adulto , Epilepsia/diagnóstico , Epilepsia/etiologia , Epilepsia/fisiopatologia , Epilepsia/psicologia , Feminino , Humanos , Masculino , Prevalência , Convulsões/epidemiologia , Convulsões/psicologia , Estresse Fisiológico , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia
10.
Med Teach ; 39(9): 906-913, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28532209

RESUMO

Increasing numbers of educators are finding it necessary to obtain advanced training in medical and health professions education. This demand has been met by a wide variety of postgraduate courses. In this Guide, we present an international consensus statement of the standards to which Master's courses in medical and health professions education should aspire.


Assuntos
Educação de Pós-Graduação em Medicina , Ocupações em Saúde/educação , Humanos
11.
Mol Genet Genomics ; 291(2): 971-88, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26786939

RESUMO

Caleosins are a class of Ca(2+) binding proteins that appear to be ubiquitous in plants. Some of the main proteins embedded in the lipid monolayer of lipid droplets, caleosins, play critical roles in the degradation of storage lipids during germination and in lipid trafficking. Some of them have been shown to have histidine-dependent peroxygenase activity, which is believed to participate in stress responses in Arabidopsis. In the model plant Arabidopsis thaliana, caleosins have been examined extensively. However, little is known on a genome-wide scale about these proteins in other members of the Brassicaceae. In this study, 51 caleosins in Brassica plants and Arabidopsis lyrata were investigated and analyzed in silico. Among them, 31 caleosins, including 7 in A. lyrata, 11 in Brassica oleracea and 13 in Brassica napus, are herein identified for the first time. Segmental duplication was the main form of gene expansion. Alignment, motif and phylogenetic analyses showed that Brassica caleosins belong to either the H-family or the L-family with different motif structures and physicochemical properties. Our findings strongly suggest that L-caleosins are evolved from H-caleosins. Predicted phosphorylation sites were differentially conserved in H-caleosin and L-caleosins, respectively. 'RY-repeat' elements and phytohormone-related cis-elements were identified in different caleosins, which suggest diverse physiological functions. Gene structure analysis indicated that most caleosins (38 out of 44) contained six exons and five introns and their intron phases were highly conserved. Structurally integrated caleosins, such as BrCLO3-3 and BrCLO4-2, showed high expression levels and may have important roles. Some caleosins, such as BrCLO2 and BoCLO8-2, lost motifs of the calcium binding domain, proline knot, potential phosphorylation sites and haem-binding sites. Combined with their low expression, it is suggested that these caleosins may have lost function.


Assuntos
Arabidopsis/genética , Brassica/genética , Proteínas de Ligação ao Cálcio/genética , Evolução Molecular , Proteínas de Plantas/genética , Sequência de Aminoácidos/genética , Proteínas de Ligação ao Cálcio/biossíntese , Proteínas de Ligação ao Cálcio/isolamento & purificação , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Germinação/genética , Filogenia , Proteínas de Plantas/biossíntese , Proteínas de Plantas/isolamento & purificação
12.
Breast J ; 22(5): 573-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27279634

RESUMO

We present the case of a 73-year-old woman with pure squamous cell carcinoma in situ of the left breast. This non-invasive malignancy exhibited pure squamous type of architectural and cytologic features without any evidence of glandular differentiation either in the initial needle core biopsy or in the subsequently performed excisional biopsy and simple mastectomy. The tumor spanned 1.6 cm, involved numerous ducts and terminal ducts and extended into lobules, and was characterized by keratinizing squamous cells with intermediate-grade nuclei. Intercellular bridges extended between the malignant squamous cells. Keratinous debris with "pearl" formation was evident in most involved glands. No invasive carcinoma was identified. There was no evidence of metastatic disease in the ipsilateral sentinel lymph nodes. Thus far, only three cases of squamous cell carcinoma in situ of the breast have been reported in one series-none of which showed any evidence of recurrent or metastatic disease at last follow-up. In our case, treated exclusively by surgery, there was no evidence of disease 11 years after diagnosis.


Assuntos
Carcinoma de Mama in situ/patologia , Neoplasias da Mama/patologia , Carcinoma de Células Escamosas/patologia , Idoso , Carcinoma de Mama in situ/cirurgia , Neoplasias da Mama/cirurgia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos
13.
Med Teach ; 36(1): 1-12, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24295273

RESUMO

This Guide discusses the considerable literature on the merits or shortcomings of Problem-based learning (PBL), and the factors that promote or inhibit it, when seen through the eyes of the student. It seems to be the case that PBL works best when students and faculty understand the various factors that influence learning and are aware of their roles; this Guide deals with each of the main issues in turn. One of the most important concepts to recognise is that students and Faculty share the responsibility for learning and there are several factors that can influence its success. They include student motivation for PBL and the various ways in which they respond to being immersed in the process. As faculty, we also need to consider the way in which the learning environment supports the students develop the habit of life-long learning, and the skills and attitudes that will help them become competent reflective practitioners. Each of these elements place responsibilities upon the student, but also upon the Faculty and learning community they are joining. Although all of the authors work in a European setting, where PBL is used extensively as a learning strategy in many medical schools, the lessons learned we suggest, apply more widely, and several of the important factors apply to any form of curriculum. This Guide follows on from a previous review in the AMEE Guides in Medical education series, which provided an overview of PBL and attempts to emphasise the key role that students have in mastering their subject through PBL. This should render the business of being a student a little less mystifying, and help faculty to see how they can help their students acquire the independence and mastery that they will need.


Assuntos
Educação de Graduação em Medicina/organização & administração , Aprendizagem Baseada em Problemas/organização & administração , Estudantes de Medicina/psicologia , Comportamento do Consumidor , Comportamento Cooperativo , Educação de Graduação em Medicina/métodos , Educação de Graduação em Medicina/normas , Docentes de Medicina , Processos Grupais , Guias como Assunto , Humanos , Relações Interpessoais , Aprendizagem Baseada em Problemas/métodos , Aprendizagem Baseada em Problemas/normas
14.
Food Chem ; 444: 138597, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38310783

RESUMO

Polar lipids have biosynthetic pathways which intersect and overlap with triacylglycerol biosynthesis; however, polar lipids have not been well characterized in the developing endosperms of oat with high oil accumulation. The polar lipids in endosperms of oat and wheat varieties having different oil contents were analyzed and compared at different developmental stages. Our study shows that the relative contents of polar lipid by mass were decreased more slowly in wheat than in oat. Phosphatidylcholine and phosphatidylethanolamine were the major phospholipids, which showed similar abundance and gradual decreases during endosperm development in oat and wheat, while lysophospholipids were noticeably higher in oat. Monogalactosyldiacylglycerol showed a gradual increase in wheat and a decrease in oat during endosperm development. The relative contents of some polar lipid species and their unsaturation index were significantly different in their endosperms. These characteristics of polar lipids might indicate an adaption of oat to accommodate oil accumulation.


Assuntos
Avena , Endosperma , Endosperma/metabolismo , Avena/metabolismo , Triticum , Lipidômica , Fosfatidilcolinas/metabolismo
16.
Med Teach ; 35(11): e1561-72, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24004029

RESUMO

There are many theories that explain how adults learn and each has its own merits. This Guide explains and explores the more commonly used ones and how they can be used to enhance student and faculty learning. The Guide presents a model that combines many of the theories into a flow diagram which can be followed by anyone planning learning. The schema can be used at curriculum planning level, or at the level of individual learning. At each stage of the model, the Guide identifies the responsibilities of both learner and educator. The role of the institution is to ensure that the time and resources are available to allow effective learning to happen. The Guide is designed for those new to education, in the hope that it can unravel the difficulties in understanding and applying the common learning theories, whilst also creating opportunities for debate as to the best way they should be used.


Assuntos
Educação Médica/métodos , Aprendizagem , Modelos Psicológicos , Estudantes de Medicina/psicologia , Ensino/métodos , Humanos , Modelos Educacionais , Motivação , Autoimagem
17.
Med Teach ; 35(12): e1638-43, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24050781

RESUMO

BACKGROUND: In this article, we consider the need for medical schools to improve the overall experience given to students by gaining appropriate feedback and ask whether the UK National Student Survey (NSS) is an appropriate tool. AIMS: We compare the currently used NSS data against data collected via an alternative, well validated, questionnaire - the Dundee Ready Education Environment Measure (DREEM). METHODS: The DREEM data was collected in January to April 2011, from the same cohort of students who were completing the UK online NSS. The NSS results were released into the public domain as frequency tables from which we calculated the standard deviations of each item. The DREEM questionnaire data were rescaled to match the NSS questionnaire data. RESULTS: The results were similar from each questionnaire, with a wide range of responses. Both DREEM and NSS data showed Assessment and Feedback to be the greatest problem, but the DREEM questions were specific, contextualised and could be used for curriculum development. CONCLUSIONS: This comparison shows the benefits of using a medical school-specific questionnaire to gain quality feedback in order to precisely alter elements of the course rather than relying on a generic questionnaire to gauge students' opinions.


Assuntos
Faculdades de Medicina/normas , Estudantes de Medicina/psicologia , Inquéritos e Questionários , Meio Ambiente , Retroalimentação , Humanos , Reino Unido
18.
Can J Surg ; 56(6): 372-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24284143

RESUMO

BACKGROUND: Intermittent claudication can be neurogenic or vascular. Physicians use a profile based on symptom attributes to differentiate the 2 types of claudication, and this guides their investigations for diagnosis of the underlying pathology. We evaluated the validity of these symptom attributes in differentiating neurogenic from vascular claudication. METHODS: Patients with a diagnosis of lumbar spinal stenosis (LSS) or peripheral vascular disease (PVD) who reported claudication answered 14 questions characterizing their symptoms. We determined the sensitivity, specificity and positive and negative likelihood ratios (PLR and NLR) for neurogenic and vascular claudication for each symptom attribute. RESULTS: We studied 53 patients. The most sensitive symptom attribute to rule out LSS was the absence of "triggering of pain with standing alone" (sensitivity 0.97, NLR 0.050). Pain alleviators and symptom location data showed a weak clinical significance for LSS and PVD. Constellation of symptoms yielded the strongest associations: patients with a positive shopping cart sign whose symptoms were located above the knees, triggered with standing alone and relieved with sitting had a strong likelihood of neurogenic claudication (PLR 13). Patients with symptoms in the calf that were relieved with standing alone had a strong likelihood of vascular claudication (PLR 20.0). CONCLUSION: The classic symptom attributes used to differentiate neurogenic from vascular claudication are at best weakly valid independently. However, certain constellation of symptoms are much more indicative of etiology. These results can guide general practitioners in their evaluation of and investigation for claudication.


CONTEXTE: La claudication intermittente peut avoir une étiologie neurogène ou vasculaire. Les médecins utilisent un profil fondé sur les particularités des symptômes pour distinguer l'une de l'autre et ceci oriente leur choix des méthodes de diagnostic de la pathologie sous-jacente. Nous avons évalué la validité de ces particularités des symptômes utilisées pour distinguer la claudication d'origine neurogène de la claudication d'origine vasculaire. MÉTHODES: Des patients atteints d'une sténose spinale lombaire (SSL) ou d'une maladie vasculaire périphérique (MVP) avérées qui se plaignaient de claudication ont réponduà 14 questions afin de caractériser leurs symptômes. Nous avons déterminé la sensibilité, la spécificité et les rapports de probabilité positifs et négatifs (RPP et RPN) à l'égard de la claudication neurogène ou vasculaire pour chacune des particularités des symptômes. RÉSULTATS: Notre étude a regroupé 53 patients. La particularité des symptômes dotée de la sensibilité la plus élevée pour ce qui est d'écarter le diagnostic de SSL a été l'absence de « déclenchement de la douleur à la simple station debout ¼ (sensibilité 0,97; RPN 0,050). Les données sur ce qui soulageait la douleur et sur la localisation des symptômes ont eu une faible portée clinique en ce qui a trait à la SSL et à la MVP. La présence d'une constellation de symptômes a donné lieu aux associations les plus solides : les patients qui manifestaient un signe du « panier d'épicerie ¼ positif et dont les symptômes étaient localisés au-dessus du genou, déclenchés par la station debout seule et soulagés en position assise présentaient une forte probabilité de claudication d'origine neurogène (RPP 13). Chez les patients dont les symptômes étaient localisés au mollet et qui étaient soulagés par la station debout, on notait une forte probabilité de claudication d'origine vasculaire (RPP 20,0). CONCLUSION: Considérés individuellement, les attributs classiques des symptômes utilisés pour distinguer la claudication d'origine neurogène de la claudication d'origine vasculaire sont au mieux faiblement valides. Toutefois, certaines constellations de symptômes éclairent bien davantage l'étiologie. Ces résultats peuvent guider l'omnipraticien dans son examen et dans son diagnostic de la claudication.


Assuntos
Claudicação Intermitente/diagnóstico , Claudicação Intermitente/etiologia , Doenças do Sistema Nervoso/complicações , Doenças Vasculares/complicações , Idoso , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
19.
Biosystems ; 227-228: 104905, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37100112

RESUMO

The increasing global demand for vegetable oils will only be met if there are significant improvements in the productivity of the major oil crops, such as oilseed rape. Metabolic engineering offers the prospect of further gains in yield beyond that already achieved by breeding and selection but requires guidance as to the changes that need to be made. Metabolic Control Analysis, through measurement and estimation of flux control coefficients, can indicate which enzymes have the most influence on a desired flux. Some experiments have previously reported flux control coefficients for oil accumulation in the seeds of oilseed rape, and others have measured control coefficient distributions for multi-enzyme segments of oil synthesis in seed embryo metabolism measured in vitro. In addition, other reported manipulations of oil accumulation contain results that are exploited further here to calculate previously unknown flux control coefficients. These results are then assembled within a framework that allows an integrated interpretation of the controls on oil accumulation from the assimilation of CO2 to deposition of oil in the seed. The analysis shows that the control is distributed to an extent that the gains from amplifying any single target are necessarily limited, but there are candidates for joint amplification that are likely to act synergistically to produce much more significant gains.


Assuntos
Brassica napus , Triglicerídeos/metabolismo , Brassica napus/metabolismo , Óleos de Plantas/metabolismo , Sementes/metabolismo
20.
BMC Plant Biol ; 12: 4, 2012 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-22233193

RESUMO

BACKGROUND: The Arabidopsis thaliana dgat1 mutant, AS11, has an oil content which is decreased by 30%, and a strongly increased ratio of 18:3/20:1, compared to wild type. Despite lacking a functional DGAT1, AS11 still manages to make 70% of WT seed oil levels. Recently, it was demonstrated that in the absence of DGAT1, PDAT1 was essential for normal seed development, and is a dominant determinant in Arabidopsis TAG biosynthesis. METHODS: Biochemical, metabolic and gene expression studies combined with genetic crossing of selected Arabidopsis mutants have been carried out to demonstrate the contribution of Arabidopsis PDAT1 and LPCAT2 in the absence of DGAT1 activity. RESULTS: Through microarray and RT-PCR gene expression analyses of AS11 vs. WT mid-developing siliques, we observed consistent trends between the two methods. FAD2 and FAD3 were up-regulated and FAE1 down-regulated, consistent with the AS11 acyl phenotype. PDAT1 expression was up-regulated by ca 65% while PDAT2 expression was up-regulated only 15%, reinforcing the dominant role of PDAT1 in AS11 TAG biosynthesis. The expression of LPCAT2 was up-regulated by 50-75%, while LPCAT1 expression was not significantly affected. In vitro LPCAT activity was enhanced by 75-125% in microsomal protein preparations from mid-developing AS11 seed vs WT. Co-incident homozygous knockout lines of dgat1/lpcat2 exhibited severe penalties on TAG biosynthesis, delayed plant development and seed set, even with a functional PDAT1; the double mutant dgat1/lpcat1 showed only marginally lower oil content than AS11. CONCLUSIONS: Collectively, the data strongly support that in AS11 it is LPCAT2 up-regulation which is primarily responsible for assisting in PDAT1-catalyzed TAG biosynthesis, maintaining a supply of PC as co-substrate to transfer sn-2 moieties to the sn-3 position of the enlarged AS11 DAG pool.


Assuntos
1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Aciltransferases/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Diacilglicerol O-Aciltransferase/metabolismo , Triglicerídeos/biossíntese , 1-Acilglicerofosfocolina O-Aciltransferase/genética , Aciltransferases/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Diacilglicerol O-Aciltransferase/genética , Análise de Sequência com Séries de Oligonucleotídeos , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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