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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

A escala de avaliação de demência (DRS) no diagnóstico de comprometimento cognitivo leve e doença de Alzheimer / The dementia rating scale (DRS) in the diagnosis of mild cognitive impairment and Alzheimer´s disease

Claudia Sellitto Porto 14 September 2006 (has links)
A Escala de Avaliação de Demência (Dementia Rating Scale -DRS), proposta por Steven Mattis (1988), tem sido bastante utilizada na avaliação de pacientes com demência tanto na atividade clínica como na pesquisa. Consiste de 5 subescalas: Atenção, Iniciativa/Perseveração, Construção, Conceituação e Memória. Neste estudo, a Escala de Avaliação de Demência foi aplicada em 56 pacientes com doença de Alzheimer com demência de intensidade leve; 55 pacientes com diagnóstico de comprometimento cognitivo leve; e, 60 indivíduos controles. Na diferenciação entre pacientes com doença de Alzheimer e controles a nota de corte de < 128 demonstrou 90,0% de sensibilidade e 89,3 % de especificidade; e, entre pacientes com doença de Alzheimer e comprometimento cognitivo leve, a nota de corte foi < 123 com sensibilidade de 78,2% e 76,8% de especificidade. Na diferenciação entre pacientes com comprometimento cognitivo leve e controles, a nota de corte foi de < 134 com 73,3% de sensibilidade e 72,7% de especificidade. A DRS demonstrou ser um instrumento com boa acurácia diagnóstica na discriminação entre pacientes com doença de Alzheimer de intensidade leve e indivíduos controles. A DRS também foi capaz de diferenciar entre pacientes com comprometimento cognitivo leve de controles, e pacientes com comprometiemnto cognitivo leve de pacientes com doença de Alzheimer de intensidade leve. As subescalas Memória e Iniciativa/Perseveração demonstraram maior acurácia diagnóstica em todas as situações analisadas quando comparadas às demais subescalas. / The Dementia Rating Scale (DRS), proposed by Steven Mattis (1988), it has been very used to assess patients with dementia both in clinical practice and research. Consists of 5 subscales: Attention, Initiation/Perseveration, Construction, Conceptualization and Memory. The Dementia Rating Scale was applied to 56 patients with Alzheimer´s disease, witha dementia of mild intensity; 55 patients with diagnosis of mild cognitive impairment; and, 60 controls. Between patients with Alzheimer´s disease and controls the cutoff score of <128 showed a 90.0% of sensitivity and 89.3% of specificity; and, between patients with Alzheimer´s disease and mild cognitive impairment, the cutoff score was <123 with sensitivity of 78.2% e 76.8% of specificity. In the analysis between patients with mild cognitive impairment and controls, the cutoff score was <134 with 73.3% of sensitivity and 72.7% of specificity. The Dementia Rating Scale showed to be a instrument with good diagnostic accuracy in the discrimination between patients with mild Alzheimer´s disease and controls. The Dementia Rating Scale also was able to discriminated between patients mild cognitive impairment and controls, and between patients with mild cognitive impairment and mild Alzheimer´s disease. The Memory and Initiation/Perseveration subscales showed good diagnostic accuracy in all analysed situations.
72

Avaliação da sensibilidade cutânea em pés de pacientes diabéticos através do Pressure Specified Sensory Device TM / Evaluation of cutaneous sensibility threshold on the feet of diabetic patients with the Pressure Specified Sensory Device(TM)

Viviane Fernandes de Carvalho 04 March 2008 (has links)
A neuropatia diabética causa diminuição ou perda da sensibilidade protetora do pé, tornando-o mais vulnerável ao trauma mecânico e térmico. A profilaxia das complicações neuropáticas tem início pela identificação da perda de sensibilidade e, portanto, do comprometimento neurológico. O Pressure Specified Sensory Device(TM) (PSSD) é um equipamento desenvolvido para quantificar o limiar de pressão, aplicada sobre a pele, necessária para que o paciente perceba o estímulo provocado por: um ponto estático, um ponto em movimento, dois pontos estáticos e dois pontos em movimento. Denominamos grupo estudo, aos trinta e quatro pacientes diabéticos do tipo 2, sem história prévia de feridas e/ou amputações nos pés que foram submetidos à avaliação de sensibilidade cutânea utilizando-se o PSSD(TM). Foram realizados testes nos territórios cutâneos dos nervos fibular profundo, plantar medial e ramo calcâneo do nervo tibial posterior. Estímulos foram provocados segundo as modalidades: um ponto estático (1 PE), um ponto em movimento (1 PD), dois pontos estáticos (2 PE) e dois pontos em movimento (2 PD), para as duas últimas modalidades. Previamente às modalidades 2PE e 2PD determinou-se o limiar de discriminação entre dois pontos estáticos (D2PE) e em movimento (D2PD). Foram realizados apenas no grupo estudo, testes com o monofilamento de Semmes-Weisntein nº 5,07 (MSW) e com o diapasão de 128 Hz. Vinte e oito pacientes não-diabéticos, submetidos aos mesmos testes, formaram o grupo controle. Para os limiares de sensibilidade, encontramos valores superiores no grupo estudo (p < 0,05). Ao compararmos os limiares de sensibilidade alcançados pelos pacientes diabéticos sensíveis e não sensíveis ao estímulo promovido pelo MSW nº 5,07 verificamos que o p-valor variou entre 0,018 < p < 0,113 para 1 PE e 0,002 < p < 0,083 para 2 PE, conforme o território cutâneo estudado. Na comparação dos limiares de sensibilidade da modalidade 1 PD entre diabéticos sensíveis e insensíveis à vibração do diapasão de 128 Hz, as diferenças não foram estatisticamente significantes (p = 0,183). Os resultados obtidos nos permitiram sugerir que o dispositivo PSSD(TM) seja utilizado como forma de acompanhamento do comprometimento da fibra nervosa. / Neuropathy is a severe progressive loss of protective sensation on the feet, making the patient more vulnerable to mechanical trauma and consequently more suitable to the development of chronic wounds, major distortion of the foot bone architecture and eventually to limb amputation. Prophylaxis should be enforced to avoid foot ulceration and for that, evaluation of the degree of loss of sensation on the skin is essential. The PSSD (Pressure Specified Sensory Device(TM)) was developed in order to quantify the threshold of pressure applied to the skin that could be recognized as positive by the patient. Pressure of one or two points is tested both statically and with movement, thus assessing the function of fast and slow response nerve fibers. Threshold of two-point discrimination was also measured in mm. Thirty four (n = 34) diabetic patients, type II, with no previous history of wounds on the lower extremity were studied using the tests, one point static (1PE), one point moving (1PD) and two points static (2 PE), and moving (2 PD) on the cutaneous territory of the fibular nerve and posterior tibial nerve (two territories - medial plantar and calcaneous nerves). The control group (28 non diabetic patients) was assessed by the same exams and the results were compared. In the diabetic group the cutaneous territories were also evaluated using the conventional Semmes-Weinstein filament nº 5,07 e vibrometer of the 128 Hz. Altered values were observed for the static and dynamic tests over the three studied nerve territories. The differences were statically significant (p < 0,05). Comparing the threshold of sensibility between sensitive and non sensitive diabetic patients to MSW nº 5,07 test, we observed that p-value range was 0,018 0,113 when 1PE test was applied, and 0,002 0,083 when 2PE test was applied, according to the cutaneous territories evaluated. Numeric quantification of the threshold of pressure allows us to determine the status of the fiber/receptor structures as well as the functional deficit of nerve fibers. Our findings suggest that PSSD(TM) is an adjuvant tool to evaluate the degree of loss of sensation on the skin.
73

Apport et utilisation des méthodes d’inférence bayésienne dans le domaine des études cliniques diagnostiques / Contribution and use of Bayesian inference methods in the field of clinical diagnostic studies

Bastide, Sophie 16 December 2016 (has links)
Les études diagnostiques correspondent à l’ensemble des études cliniques qui ont pour objectif l’évaluation d’un nouveau test diagnostique. Dans la démarche d’évaluation, l’étape centrale est l’évaluation de la performance du nouveau test par estimation de sa sensibilité et de sa spécificité. De manière classique, la performance du nouveau test est évaluée par comparaison à un test de référence supposé parfait, appelé un « gold standard » qui permet la connaissance du statut réel de chaque sujet vis-à-vis de la pathologie étudiée. Cependant, dans de très nombreuses situations cliniques, différentes difficultés existent : l’absence de gold standard parfait, l’impossibilité de réalisation du gold standard à tous les sujets, la dépendance des résultats des tests réalisés, la variabilité de la sensibilité et/ou de la spécificité du test en fonction de certaines conditions de réalisation, la multiple réalisation du test dans le temps ou sa multiple interprétation.Une revue méthodologique systématique a été effectuée pour faire l’état des lieux des méthodes d’inférence bayésienne disponibles dans les études diagnostiques et de leur utilisation en pratique. Le focus sur les méthodes bayésiennes a été retenu du fait de leurs avantages théoriques contrastant avec leur relative sous-utilisation dans le domaine médicale. Actuellement, de nombreuses méthodes ont été proposées pour répondre à ces différentes difficultés, avec des développements très complexes en cas de combinaison de plusieurs difficultés dans une même situation. Nous avons ainsi pu établir une cartographie des combinaisons de méthodes disponibles. Cependant leur utilisation en clinique reste encore limitée, même si elle est en augmentation ces dernières années.En pratique, nous avons été confrontés à la problématique du diagnostic de pneumopathie à Pneumocystis jirovecii (PJ) (champignon ubiquitaire opportuniste responsable de mycose profonde chez les patients immunodéprimés). Dans ce projet, nous disposions des résultats de quatre techniques de PCR (Polymerase chain reaction) différentes mais sans gold standard, avec la difficulté supplémentaire de dépendance conditionnelle entre les tests du fait du principe commun à l’origine de ces quatre tests. Deux développements ont été réalisés en parallèle pour répondre à cette problématique : d’une part, un travail sur les méthodes d’élicitation des informations a priori adaptées spécifiquement aux études diagnostiques, et d’autre part, un travail de mise en œuvre d’un modèle statistique adapté à la problématique de quatre tests dépendants en l’absence de gold standard. En l’absence de données informatives dans la littérature, l’élicitation des a priori, étape obligatoire pour l’utilisation des méthodes d’inférence bayésienne, est réalisée par l’interrogation d’experts du domaine. Notre travail a consisté en une adaptation des méthodes existantes, disponibles dans le domaine des essais cliniques, spécifiquement aux études diagnostiques pour obtenir des a priori informatifs. Cette méthode a été appliquée à notre cas des PCR diagnostiques pour PJ. L’estimation des performances diagnostiques des tests en l’absence de gold standard repose de manière efficiente sur les modèles à classes latentes. Trois modèles ont été développés pour le cas de deux tests diagnostiques : un modèle à indépendance conditionnelle, un modèle à dépendance conditionnelle à effets fixes et un modèle à dépendance conditionnelle à effets aléatoires. Nous proposons dans cette thèse une adaptation de ces trois modèles à la situation de quatre tests diagnostiques avec une formulation des paramètres permettant une interprétation clinique des covariances entre les tests dans un souci de transmission des méthodes de la théorie à la pratique. Une application et une comparaison de ces modèles ont été faites pour l’estimation des sensibilités et spécificités des quatre techniques de PCR à PJ en utilisant les a priori informatifs obtenus auprès des experts. / Diagnostic studies include all clinical studies the aim of which is the evaluation of a new diagnostic test. In the evaluation process, the main step is the evaluation of the performance of the new test i.e. its sensitivity and specificity. Usually, the performance of a new test is assessed by comparison to a test of reference which is supposed to be perfect, i.e. a "gold standard", and specifies the actual patient’s status for the disease of interest (“Diseased” or “Not-Diseased” status). However, in many clinical situations, different pitfalls exist such as (i) a gold standard is not available, (ii) the gold standard is not applicable to all patients, (iii) a conditional dependence exists between test results, (iv) the performance of a test is not constant and depends on the conditions of achievement of the test, (v) the tests are repeated in time or by several machines or read by several readers, together with multiple interpretation of the results. A systematic methodological review has been performed to inventory all Bayesian inference methods available in the field of diagnostic studies and their use in practice. The focus on Bayesian methods was based on the theoretical advantages of these methods contrasting with their relative underutilization in the medical field. Finally, several interesting methods have been proposed to address methodological issues of diagnostic studies, with very complex developments when several issues were combined in the same clinical situation. We propose to map the development methods and combinations that have already been done or not. However, their clinical use is still limited, although it has increased in recent years.In practice, we met the problem of the diagnosis of pneumonia due to Pneumocystis jirovecii (PJ). PJ is an ubiquitous opportunistic fungus leading to deep mycosis in immunocompromised patients. In this study, the results of four PCR (polymerase chain reaction) assays were available, but without any gold standard, and the supplementary difficulty of conditional dependence between tests because the four tests were based on the same principle. Two works were performed in parallel to address this issue: on one hand, an adaptation of methods to elicit prior information specifically in diagnostic studies, and on the other hand, the implementation of specific Bayesian statistical models adapted to the context of four-dependent tests in the absence of gold standard. When informative information is not available in the literature, the elicitation of priors, the mandatory first step of a Bayesian inference, is carried out by registering experts’ beliefs in the field. Our work consisted in an adaptation of existing methods, available in clinical trials, specifically for diagnostic studies to obtain informative priors. We then applied this method to our four PJ PCR assays. Estimation of the diagnostic test performance in absence of gold standard is efficiently based on latent class models (LCM). Three LCM were developed for the case of two diagnostic tests: a simple LCM assuming conditional independence between tests, a fixed effects LCM and a random effects LCM providing an adjustment for conditional dependence between tests. We extended these three models to a situation where four diagnostic tests are involved and proposed a formulation that enables an interpretation of between tests covariances in a clinical perspective in order to bind theory to practice. These models were then applied and compared in an estimation study of the sensitivities and specificities of the four PJ PCR assays, by using informative priors obtained from experts.
74

Considerations for Identifying and Conducting Cluster Randomized Trials / Considerations For Identifying and Conducting Cluster Trials

Al-Jaishi, Ahmed January 2021 (has links)
Background: The cluster randomized trial design randomly assigns groups of people to different treatment arms. This dissertation aimed to (1) develop machine learning algorithms to identify cluster trials in bibliographic databases, (2) assess reporting of methodological and ethical elements in hemodialysis-related cluster trials, and (3) assess how well two covariate-constrained randomization methods balanced baseline characteristics compared with simple randomization. Methods: In study 1, we developed three machine learning algorithms that classify whether a bibliographic citation is a CRT report or not. We only used the information available in an article citation, including the title, abstract, keywords, and subject headings. In study 2, we conducted a systematic review of CRTs in the hemodialysis setting to review the reporting of key methodological and ethical issues. We reviewed CRTs published in English between 2000 and 2019 and indexed in MEDLINE or EMBASE. In study 3, we assessed how well two covariate-constrained randomization methods balanced baseline characteristics compared with simple randomization. Results: In study 1, we successfully developed high-performance algorithms that identified whether a citation was a CRT. Our algorithms had greater than 97% sensitivity and 77% specificity in identifying CRTs. For study 2, we found suboptimal conduct and reporting of methodological issues of CRTs in the hemodialysis setting and incomplete reporting of key ethical issues. For study 3, where we randomized 72 clusters, constraining the randomization using historical information achieved a better balance on baseline characteristics than simple randomization; however, the magnitude of benefit was modest. Conclusions: This dissertation's results will help researchers quickly identify cluster trials in bibliographic databases (study 1) and inform the design and analyses of future Canadian trials conducted within the hemodialysis setting (study 2 & 3). / Thesis / Doctor of Philosophy (PhD) / The cluster trial design randomly assigns groups of people to different treatment arms rather than individuals. Cluster trials are commonly used in research areas such as education, public health, and health service research. Examples of clusters can include villages/communities, worksites, schools, hospitals, hospital wards, and physicians. This dissertation aimed to (1) develop machine learning algorithms to identify cluster trials in bibliographic databases, (2) assess reporting of methodological and ethical elements in hemodialysis-related cluster trials, and (3) identified best practices for randomly assigning hemodialysis centers in cluster trials. We conducted three studies to address these aims. The results of this dissertation will help researchers quickly identify cluster trials in bibliographic databases (study 1) and inform the design and analyses of future Canadian trials conducted within the hemodialysis setting (study 2 & 3).
75

Identification of H. Pylori in Saliva by a Nested PCR Assay Derived From a Newly Cloned DNA Probe

Jiang, C, Li, C, Ha, T, Ferguson, D. A., Chi, D. S., Laffan, J. J., Thomas, E. 01 June 1998 (has links)
A novel probe was developed from genomic DNA of Helicobacter pylori ATCC type strain 43629. It hybridized with all 73 H. pylori clinical isolates tested but not with any of 183 non-H. pylori DNAs in dot blot hybridization. Typing tests revealed 41 different HaeIII-digestion patterns from 57 H. pylori strains tested. Based on the sequence of the probe, a nested PCR was developed that detected as little as 2 fg of H. pylori DNA or approximately equivalent to one cell. No PCR products were amplified from any of 21 non-H. pylori strains tested. Using this nested PCR, H. pylori DNA was detected in 33 of 45 (73%) saliva samples collected from patients with gastric H. pylori infection. These data suggest that the probe is useful for typing H. pylori and that the nested PCR is a valuable tool for detecting H. pylori DNA in saliva.
76

Imunohromatografski test u diferencijalnoj laboratorijskoj dijagnostici tuberkuloze pluća / Immunochromatographic test in differential laboratory diagnostic of tuberculosis

Savković Tijana 01 April 2016 (has links)
<p>UVOD: Tuberkuloza je odavno poznata bolest koja i danas u 21. veku jo&scaron; uvek predstavlja veliki javnozdravstveni problem, uprkos primeni moćnih antituberkuloznih lekova. Trećina svetske populacije inficirana je bacilom tuberkuloze. Svake godine oboli oko osam miliona, a umre oko dva miliona ljudi, zbog čega je tuberkuloza i dalje infektivno oboljenje sa najvećom stopom smrtnosti. Kasna dijagnoza, multirezistentna tuberkuloza i udruženost sa HIV infekcijom predstavljaju jednu od najvećih prepreka za efikasnu kontrolu ove bolesti u svetu. Rano otkrivanje se oslanja na kvalitetnu bakteriolo&scaron;ku dijagnostiku koja je kamen temeljac svakog nacionalnog programa za kontrolu tuberkuloze. Brza i tačna mikrobiolo&scaron;ka dijagnostika predstavlja osnovu programa kontrole tuberkuloze i zbog toga je uvođenje novih i brzih laboratorijskih testova od veoma velikog značaja. Razvijen je novi komercijalno dostupni imunohromatografski test koji se zasniva na detekciji antigena MPT64 glavnog sekretovanog proteina M. tuberculosis. Test je brz i pouzdan u identifikaciji izolovanih sojeva M. tuberculosis i jeftiniji je od konvencionalnih biohemijskih i molekularnih testova. CILJ: Ciljevi istraživanja su bili da se evaluiraju karakteristike novog brzog imunohromatografskog testa u identifikaciji mikobakterija izolovanih iz respiratornih uzoraka bolesnika sa tuberkulozom pluća i referentnih sojeva klinički značajnih vrsta netuberkuloznih mikobakterija (NTM). MATERIJAL I METODE: Istraživanje je sprovedeno u periodu od 1.1.2010. do 31.12.2013. i obuhvatilo je 43563 respiratornih uzoraka dobijenih od bolesnika hospitalizovanih u Institutu za plućne bolesti Vojvodine. Iz obrađenih respiratornih uzoraka izolovano je 3469 izolata mikobakterija. Identifikacija do nivoa vrste urađena je primenom standardnih biohemijskih testova, molekularnog testa (GenoType&reg; Mycobacterium) i imunohromatografskog testa (BDMGIT Tbc). U istraživanje je uključeno 100 sojeva Gram pozitivnih i Gram negativnih bakterija (n = 19 vrsta) izolovanih iz respiratornih kliničkih uzoraka. Identifikacija do nivoa vrste je potvrđena komercijalnim identifikacionim sistemima. REZULTATI: U toku četvorogodi&scaron;njeg istraživanja izolovano je 3469 izolata mikobakterija iz respiratornih uzoraka. U ispitivanom periodu ne postoji opadajući trend izolacije mikobakterija &scaron;to potvrđuje i koeficijent korelacije (r = 0,31). Svi izolati mikobakterija su identifikovani konvencionalnim biohemijskim ispitivanjima koja pokazuju da je 89% od svih izolata identifikovano kao Mycobacterium tuberculosis (M. tuberculosis), a 11% izolata kao NTM. Mycobacterium xenopi je bila najzastupljenija NTM vrsta identifikovana kod 55,3% izolata. Nakon biohemijske identifikacije kod 300 izolata M. tuberculosis i 100 izolata NTM, identifikacija je potvrđena komercijalno dostupnim molekularnim i imunohromatografskim testom. Na osnovu rezultata testiranja mikobakterija imunohromatografskim testom, senzitivnost, specifičnost, pozitivne i negativne prediktivne vrednosti bile su: 99,7%, 100%, 100% i 99%. U poređenju imunohromatografskog testa sa konvencionalnim biohemijskim ispitivanjima nije nađena statistički značajna razlika (p&gt; 0,5). Kappa vrednost testa je iznosila 0,993, a interval poverenja CI =0,98 &ndash; 1,00. U poređenju imunohromatografskog sa molekularnim testom vrednost kappa je iznosila 0,993, a interval poverenja CI = 0,98 &ndash; 1,00. Slaganje rezultata je potvrđeno i McNemar testom sa vredno&scaron;ću 0,99. Utvrđena je stabilnost sekretovanog antigena MPT64 i posle 5 godina od prvog testiranja. ZAKLJUČAK: Visoka senzitivnost i specifičnost imunohromatografskog testa omogućuju tačnu i preciznu identifikaciju M. tuberculosis kao i pouzdanu diferencijaciju M.tuberculosis od NTM &ndash; a. Imunohromatografski test može da predstavlja zamenu za konvencionalne biohemijske i molekularne testove u identifikaciji M. tuberculosis. Jeftiniji je, jednostavniji za izvođenje i brže se dobijaju rezultati čime seskraćuje vreme za postavljanje dijagnoze.</p> / <p>INTRODUCTION: Tuberculosis (TB) has been known as a disease for a long time, but nevertheless it represents a major public health issue even nowadays in the 21st century, despite potent antituberculous drugs applied. One third of the world population is infected by the TB bacillus. About eight million people get infected and two million die of tuberculosis in a year, so tuberculosis is still an infectious disease with the greatest mortality rate. Late diagnosis, multiresistant tuberculosis and concomitant HIV infection interfere mostly with an efficient control of the disease all over the world. Early TB detection largely depends on the high-quality bacteriological diagnostics, which is the corner stone of each national TB control programme. A fast and accurate microbiological TB diagnosis plays a crucial role in any TB control programme. It is therefore very important to introduce new and fast laboratory tests. A novel commercially available immunochromatographic test has been designed, based on the MPT64 antigen of the major M. tuberculosis &ndash; secreted protein. This is a rapid and reliable test to identify the isolated strains of M. tuberculosis, which is not expensive as conventional biochemical and molecular tests. OBJECTIVE: The objective of the investigation was to evaluate the new immunochromatographic rapid test to identify mycobacteria isolated from respiratory samples from pulmonary TB patients, and referential strains of clinically relevant species of nontuberculous mycobacteria (NTM). MATERIAL AND METHODS: The research was carried out in the period from 1st January, 2010 to 31st December, 2013. It included 43 563 respiratory samples obtained from the patients hospitalized in the Institute for Pulmonary Diseases of Vojvodina, Sremska Kamenica (Serbia). There were 3 469 mycobacterial isolates obtained from the processed respiratory samples. The species &ndash; level identification was performed by standard biochemical tests, the molecular test (GenoType&reg;Mycobacterium), and the immunochromatographic test (BD MGIT Tbc). The study included one hundred (100) of Gram positive and Gram negative bacteria (n = 19 species) isolated from respiratory clinical samples. The species &ndash; level identification was confirmed by commercial identification systems. RESULTS: During the four &ndash; year investigation, 3 469 mycobacterial isolates were obtained from respiratory samples. No declining tendency of mycobacterial isolation was registered in the examined period, as confirmed by the correlation coefficient (r = 0.31). All mycobacterial isolates were identified by conventional biochemical tests showing that 89% of all isolates were identified as M. tuberculosis, and 11% of the isolates as NTM. Mycobacterium xenopi was the most common NTM species identified in 55.3% of the isolates. Following the biochemical identification in 300 M. tuberculosis isolates and 100 NTM isolates, the identification was confirmed by commercially available molecular and immunochromatographic tests. Based on immunochromatographic testing of mycobacteria, the sensitivity, specificity, positive and negative predictive values of the test were 99.7%, 100%, 100% and 99% respectively. There is no statistically significant difference (p&gt; 0.5) when comparing features of immunochromatographic test with conventional biochemical assay. The kappa test value was 0.993, and the confidence interval CI = 0.98 &ndash; 1.00. Comparing the immunochromatographic with the molecular test, the kappa value was 0.993, and the confidence interval CI = 0.98 &ndash; 1.00. The congruence of the tests findings was also confirmed by the McNemar test, estimated to 0.99. The stability of the secreted MPT64 antigen was registered even five years after the first testing episode. CONCLUSION: The high sensitivity and specificity of the imunochromatographic test enable an accurate and precise identification of M. tuberculosis, as well as a reliable differentiation of M. tuberculosis from NTM. The immunochromatographic test may substitute conventional biochemical and molecular tests to identify M. tuberculosis. It is easier to perform and provides faster test results, thus reducing the time of establishing the diagnosis.</p>
77

Comparação do comprimento do úmero em fetos portadores de Síndrome de Down com o comprimento do úmero em fetos normais / Comparison of humeral length between fetuses with Down syndrome and normal fetuses

Silva, Rimena de Melo Germano da 19 February 2014 (has links)
Objetivo: Comparar o comprimento do úmero em fetos portadores de síndrome de Down (T21) com o comprimento do úmero em fetos normais, utilizando instrumentos de referência da população local. Método: Estudo caso-controle retrospectivo que comparou o comprimento do úmero de fetos normais com os fetos com T21, entre 18 semanas e 23 semanas e 6 dias. Os exames dos fetos com T21 foram realizados entre 1994 e 2012. Os controles normais foram avaliados entre 2007 e 2009. Foram analisadas as médias, medianas e desvios-padrão da idade materna, idade gestacional e medida do úmero. Posteriormente, foi feita análise da correlação entre as medidas dos úmeros e a idade gestacional, sendo seus valores expressos em múltiplos da mediana (MoMs). O comprimento do úmero dos fetos com T21 foram confrontados com os fetos normais utilizando o teste t-Student. A medida do úmero foi avaliada considerando-se os níveis de corte abaixo do percentil 10, 5 e 2,5 a fim de obter as respectivas taxas de sensibilidade. Calculou-se, ainda, a razão de verossimilhança (RV). A seguir, foi utilizado um modelo linear geral tendo a idade materna como covariável para controlar na comparação. Comparou-se, também, a medida do comprimento do úmero dos fetos normais da população local com o comprimento do úmero esperado baseado na curva de Jeanty. Os testes foram realizados com nível de significância de 5%. Resultados: Foram incluídos 58 casos com T21 e 1888 controles normais. A sensibilidade do comprimento do úmero para a detecção da T21 utilizando o nível de corte abaixo do percentil 10 foi de 44,8 % com RV de 4,4, abaixo do percentil 5 foi de 34,4 % com RV de 6,9 e abaixo do percentil 2,5 foi de 31,0 % com RV de 12. O valor médio dos úmeros, em MoMs, de fetos com T21 é estatisticamente inferior ao dos fetos normais (p < 0,001), utilizando o teste t-Student. Quando controlada a idade materna na comparação entre os grupos, a diferença permaneceu estatisticamente significativa (p < 0,001). Fez-se uma análise para comparar o comprimento do úmero nos fetos normais da população local com o comprimento do úmero esperado para a curva de Jeanty, e viu-se que os fetos normais locais têm comprimento do úmero estatisticamente significante menor. Conclusões: Existe diferença estatisticamente significante entre o comprimento do úmero de fetos normais e de fetos com T21 na população local (p < 0,001). A sensibilidade para detecção de T21 foi de 44,8%, 34,4% e 31%, para o úmero abaixo do percentil 10, 5 e 2,5, respectivamente. A curva de Jeanty não tem rendimento adequado para uso como controle do crescimento umeral em fetos normais locais, acarretando com seu uso o inevitável aumento da taxa de falsos positivos de úmeros curtos / Objective: This study aimed to compare the humeral length (HL) in fetuses with Down syndrome (T21) with HL in normal fetuses, by using instruments of reference of the local population. Method: A case-control study was conducted comparing HL in normal fetuses with HL in fetuses with T21, aged between 18 weeks and 23 weeks and 6 days. Fetuses with T21 who were examined between 1994 and 2012 were included. The normal controls were evaluated between 2007 and 2009. The averages, medians, and standard deviations were obtained for maternal age, gestational age, and HL. Afterwards, we analyzed the correlation between the HL and the gestational age, with values expressed as multiples of the median (MoMs). The HLs of fetuses with T21 were compared with the HLs in normal fetuses by using Student\'s t-test. The humeri were evaluated considering the cut-off levels below the 10th, 5th, and 2,5th percentiles to obtain the sensitivity. The likelihood ratios (LR) were also calculated. Next, a general linear model was used with maternal age as a covariate to control for comparison of the groups. Comparison was also made between the HL of fetuses in the local population and the expected HL, based on the Jeanty curve. The tests were performed with a significance level of 5%. Results: The study included 58 cases with T21 and 1888 normal controls. The sensitivity of the HL to detect T21 by using a cut-off level below the 10th percentile was 44.8% with a LR of 4.4; below the 5th percentile, the sensitivity was 34.4% with a LR of 6.9; and below the 2.5th percentile, the sensitivity was 31.0% with a LR of 12. The average value of the humerus, in MoMs, of fetuses with T21 is statistically lower than that of normal fetuses (p < 0.001), as measured by using Student\'s t-test. When maternal age was controlled as a covariant in the comparison between groups, the difference remained statistically significant (p < 0.001). An analysis to compare the HL in normal fetuses of the local population with expected HL based on the Jeanty curve concluded that the HL in normal fetuses of the local population is lower than expected. Conclusions: There is a statistically significant difference between the HL of normal fetuses and HL of fetuses with T21 in the local population (p < 0.001). The sensitivity for detection of T21 was 44.8%, 34.4%, and 31% for the humerus below the 10th, 5th and 2.5th percentile, respectively. The Jeanty curve is not adequate to use as growth control for humeri in local normal fetuses, as its use leads to an increase in false positive rates when measuring the proportion of short humeri
78

Determinação do genótipo RHD fetal no plasma materno: acurácia do teste semiautomatizado / Fetal RHD genotype determination in maternal plasma: Accuracy of a semi-automated test

Ziza, Karen Nogueira Chinoca 18 November 2015 (has links)
INTRODUÇÃO: A determinação do genótipo RHD fetal no plasma materno é um teste de diagnóstico pré-natal não invasivo oferecido a gestantes RhD negativo que apresentam potencial de sensibilização e/ou Doença Hemolítica Perinatal. Atualmente, este exame é realizado de rotina em diversos países, mas não no Brasil. A Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) oferece atendimento terciário a gestantes RhD negativo, com monitorização dos títulos de anticorpos irregulares, administração da imunoglobulina anti-D e/ou terapêutica fetal, quando necessários. OBJETIVO: Avaliar a acurácia do teste semiautomatizado para determinação do genótipo RHD fetal no plasma materno. METODOLOGIA: Foram coletadas prospectivamente amostras de sangue de 220 gestantes RhD negativo, com idade gestacional entre 8-28 semanas. O plasma foi obtido em no máximo 2 horas após a coleta, e uma alíquota de 1 mL foi submetida à extração de ácidos nucléicos no equipamento automatizado MagNA Pure Compact (Roche), empregando o kit Large Volume. O DNA extraído foi submetido a PCR em tempo real (Step One Plus - Applied Biosystems), usando o protocolo do grupo SAFE, que tem como alvos os éxons 5 e 7 do gene RHD. RESULTADOS: Ocorreu exclusão de 35 amostras devido a problemas pré-analíticos, aborto ou desconhecimento do fenótipo do recém-nascido. Entre as 185 amostras analisadas, 130 (70,2%) foram genotipadas como RHD+ e 55 (29,8%) RHD-. Os resultados obtidos foram comparados com a fenotipagem do cordão umbilical, e houve concordância completa (100%). Sete amostras exibiram amplificação exclusiva para o éxon 7. Essas amostras foram submetidas aos protocolos em PCR convencional, e PCR em tempo real específico para o pseudogene RHD. Ambos os ensaios apresentaram os mesmos resultados: cinco positivos e dois negativos. Nesses mesmos 7 casos, após extração da camada de leucócitos materna, os protocolos foram repetidos, e o resultado confirmou que cinco mães eram RHD. As duas amostras com resultado negativo foram submetidas ao protocolo Multiplex, envolvendo os éxons 3-9 do gene RHD, com resultados negativos, confirmando que as mães são verdadeiramente RHD- portanto o sinal do éxon 7 é provindo dos fetos que são D variantes. CONCLUSÃO: O método para a determinação do RHD fetal no plasma materno descrito demonstrou ser rápido, de fácil execução, alta precisão e reprodutível, além de indicar possíveis variantes RHD em nossa população / BACKGROUND: Fetal RHD genotype determination in maternal plasma is a noninvasive prenatal diagnostic test performed in RhD negative pregnant women at risk of alloimmunization and/or Hemolytic Disease of Fetus and Newborn. Currently, this test is routinely performed in many countries but not in Brazil. The Department of Obstetrics at Hospital das Clínicas, São Paulo University Medical School provides tertiary antenatal care for RhD negative pregnant women including anti-D immunoglobulin administration, antibody levels monitoring and intrauterine treatment if necessary. AIMS: To validate the accuracy of a semi-automated test for fetal RHD genotype determination in maternal plasma. METHODS: Two-hundred and twenty blood samples were prospectively collected between 8 and 28 weeks of gestational age. Plasma processing was performed within 2 hours after blood collection, and nucleic acids were extracted from 1mL aliquots with an automated extraction platform (MagNA Pure Compact Roche) and the Large Volume kit. RHD gene exons 5 and 7 were amplified with real-time PCR (Step One Plus - Applied Biosystems) using the SAFE group protocol. RESULTS: Thirty-five samples were excluded due to pre-analytical problems, miscarriage and missing follow-up. In the remaining 185 samples, 130 (70.2%) were genotyped as RhD+ and 55 (29.8%) RhD-. Comparison with umbilical cord blood group phenotype showed 100% concordance. Seven samples showed amplification for exon 7 only. These were further investigated with conventional and real-time PCR with an specific protocol for RHD? pseudogene: 5 were positive and 2, negative. In these 7 cases, maternal buffy-coat DNA analysis also confirmed that 5 women were RHD?. In the remaining 2 cases, a multiplex protocol directed at RHD gene exons 3-9 confirmed that both mothers were truly RhD negative so exon 7 signal comes from the fetuses, further found to harbor D variants. CONCLUSION: The present study demonstrates that fetal RHD determination in maternal plasma is a fast, easy-to-perform and reproducible technique with high accuracy in our population. Moreover, it helps in the identification of possible RHD variants in our population
79

Predição de malignidade de tumores ovarianos utilizando marcadores tumorais, índice de risco e ROMA / Prediction of malignancy of ovarian tumors using tumor markers, risk index and ROMA

Anton, Cristina 29 September 2011 (has links)
INTRODUÇÃO: O câncer de ovário é o mais letal de todos os cânceres ginecológicos e requer ser tratado por ginecologistas especializados em centros terciários para se obter melhor prognóstico. Este trabalho tem como objetivo analisar e comparar quatro estratégias diferentes para predizer a benignidade ou malignidade de tumores pélvicos supostamente de origem ovariana utilizando para este fim, marcadores tumorais CA 125 e HE4, índice de risco de malignidade (IRM) e algoritmo ROMA. MÉTODOS: Neste estudo prospectivo foram avaliadas 128 pacientes com diagnóstico de tumores pélvicos supostamente de origem ovariana atendidas na Divisão de Clínica Ginecológica do Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo e Instituto do Câncer do Estado de São Paulo entre julho de 2008 e janeiro 2011. Foram calculadas a sensibilidade e a especificidade e construídas curvas ROC para comparar os quatro parâmetros (CA 125, HE4, ROMA e IRM) na eficácia de diferenciar tumores ovarianos. RESULTADOS: A sensibilidade obtida para CA 125, HE4, ROMA e IRM foi de, respectivamente, 70,4%, 79,7%, 74,1% e 63,0%. A especificidade para CA 125, HE4, ROMA e IRM foi de, respectivamente, 74,2%, 66,7%, 75,8% e 92,4%. Não houve diferença na comparação das áreas abaixo da curva ROC entre os quatro parâmetros. CONCLUSÕES: Nenhum dos quatro métodos estudados é o ideal na diferenciação de tumores ovarianos. Entre os quatro parâmetros analisados o HE4 foi o parâmetro com melhor sensibilidade na diferenciação de tumores ovarianos. A acurácia dos quatro métodos é equivalente e podem ser utilizados indistintamente para referenciar pacientes para serviços especializados no tratamento de câncer de ovário / BACKGROUND: Ovarian cancer is the most lethal of all gynecological cancers and requires to be treated by gynecologic oncologists in tertiary centers accustomed to treating this disease to achieve the best prognosis. This study aims to compare four different strategies to predict the benignity or malignancy of pelvic tumors presumably of ovarian origin using, for this purpose, tumor markers CA 125 and HE4, risk malignancy index (RMI) and algorithm ROMA. METHODS: This prospective study evaluated 128 patients supposedly with ovarian tumors treated at the Divisão de Clínica Ginecológica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo and at Instituto do Câncer do Estado de São Paulo between July 2008 and January 2011. We calculated sensitivity, specificity and ROC curves to compare the four parameters (CA 125, HE4, ROMA and RMI) ability to differentiate the ovarian tumors. RESULTS: The sensitivity obtained for CA 125, HE4, ROMA and RMI was, respectively, 70.4%, 79.7%, 74.1% and 63.0%. The specificity obtained for CA 125, HE4, ROMA and RMI was, respectively, 74.2%, 66.7%, 75.8% and 92.4%. There was no difference the areas under the ROC curve among the four parameters. CONCLUSIONS: None of the four studied methods is best in the differentiation of ovarian tumors. Among the four parameters analyzed, HE4 was the parameter with highest sensitivity in the differentiation of ovarian tumors. The accuracy of the four methods is equivalent and can be used interchangeably to refer patients for specialized services in the treatment of ovarian cancer
80

Determinação do genótipo RHD fetal no plasma materno: acurácia do teste semiautomatizado / Fetal RHD genotype determination in maternal plasma: Accuracy of a semi-automated test

Karen Nogueira Chinoca Ziza 18 November 2015 (has links)
INTRODUÇÃO: A determinação do genótipo RHD fetal no plasma materno é um teste de diagnóstico pré-natal não invasivo oferecido a gestantes RhD negativo que apresentam potencial de sensibilização e/ou Doença Hemolítica Perinatal. Atualmente, este exame é realizado de rotina em diversos países, mas não no Brasil. A Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) oferece atendimento terciário a gestantes RhD negativo, com monitorização dos títulos de anticorpos irregulares, administração da imunoglobulina anti-D e/ou terapêutica fetal, quando necessários. OBJETIVO: Avaliar a acurácia do teste semiautomatizado para determinação do genótipo RHD fetal no plasma materno. METODOLOGIA: Foram coletadas prospectivamente amostras de sangue de 220 gestantes RhD negativo, com idade gestacional entre 8-28 semanas. O plasma foi obtido em no máximo 2 horas após a coleta, e uma alíquota de 1 mL foi submetida à extração de ácidos nucléicos no equipamento automatizado MagNA Pure Compact (Roche), empregando o kit Large Volume. O DNA extraído foi submetido a PCR em tempo real (Step One Plus - Applied Biosystems), usando o protocolo do grupo SAFE, que tem como alvos os éxons 5 e 7 do gene RHD. RESULTADOS: Ocorreu exclusão de 35 amostras devido a problemas pré-analíticos, aborto ou desconhecimento do fenótipo do recém-nascido. Entre as 185 amostras analisadas, 130 (70,2%) foram genotipadas como RHD+ e 55 (29,8%) RHD-. Os resultados obtidos foram comparados com a fenotipagem do cordão umbilical, e houve concordância completa (100%). Sete amostras exibiram amplificação exclusiva para o éxon 7. Essas amostras foram submetidas aos protocolos em PCR convencional, e PCR em tempo real específico para o pseudogene RHD. Ambos os ensaios apresentaram os mesmos resultados: cinco positivos e dois negativos. Nesses mesmos 7 casos, após extração da camada de leucócitos materna, os protocolos foram repetidos, e o resultado confirmou que cinco mães eram RHD. As duas amostras com resultado negativo foram submetidas ao protocolo Multiplex, envolvendo os éxons 3-9 do gene RHD, com resultados negativos, confirmando que as mães são verdadeiramente RHD- portanto o sinal do éxon 7 é provindo dos fetos que são D variantes. CONCLUSÃO: O método para a determinação do RHD fetal no plasma materno descrito demonstrou ser rápido, de fácil execução, alta precisão e reprodutível, além de indicar possíveis variantes RHD em nossa população / BACKGROUND: Fetal RHD genotype determination in maternal plasma is a noninvasive prenatal diagnostic test performed in RhD negative pregnant women at risk of alloimmunization and/or Hemolytic Disease of Fetus and Newborn. Currently, this test is routinely performed in many countries but not in Brazil. The Department of Obstetrics at Hospital das Clínicas, São Paulo University Medical School provides tertiary antenatal care for RhD negative pregnant women including anti-D immunoglobulin administration, antibody levels monitoring and intrauterine treatment if necessary. AIMS: To validate the accuracy of a semi-automated test for fetal RHD genotype determination in maternal plasma. METHODS: Two-hundred and twenty blood samples were prospectively collected between 8 and 28 weeks of gestational age. Plasma processing was performed within 2 hours after blood collection, and nucleic acids were extracted from 1mL aliquots with an automated extraction platform (MagNA Pure Compact Roche) and the Large Volume kit. RHD gene exons 5 and 7 were amplified with real-time PCR (Step One Plus - Applied Biosystems) using the SAFE group protocol. RESULTS: Thirty-five samples were excluded due to pre-analytical problems, miscarriage and missing follow-up. In the remaining 185 samples, 130 (70.2%) were genotyped as RhD+ and 55 (29.8%) RhD-. Comparison with umbilical cord blood group phenotype showed 100% concordance. Seven samples showed amplification for exon 7 only. These were further investigated with conventional and real-time PCR with an specific protocol for RHD? pseudogene: 5 were positive and 2, negative. In these 7 cases, maternal buffy-coat DNA analysis also confirmed that 5 women were RHD?. In the remaining 2 cases, a multiplex protocol directed at RHD gene exons 3-9 confirmed that both mothers were truly RhD negative so exon 7 signal comes from the fetuses, further found to harbor D variants. CONCLUSION: The present study demonstrates that fetal RHD determination in maternal plasma is a fast, easy-to-perform and reproducible technique with high accuracy in our population. Moreover, it helps in the identification of possible RHD variants in our population

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