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2.
Insights Imaging ; 13(1): 122, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35900673

RESUMO

BACKGROUND: The role of chest radiography in COVID-19 disease has changed since the beginning of the pandemic from a diagnostic tool when microbiological resources were scarce to a different one focused on detecting and monitoring COVID-19 lung involvement. Using chest radiographs, early detection of the disease is still helpful in resource-poor environments. However, the sensitivity of a chest radiograph for diagnosing COVID-19 is modest, even for expert radiologists. In this paper, the performance of a deep learning algorithm on the first clinical encounter is evaluated and compared with a group of radiologists with different years of experience. METHODS: The algorithm uses an ensemble of four deep convolutional networks, Ensemble4Covid, trained to detect COVID-19 on frontal chest radiographs. The algorithm was tested using images from the first clinical encounter of positive and negative cases. Its performance was compared with five radiologists on a smaller test subset of patients. The algorithm's performance was also validated using the public dataset COVIDx. RESULTS: Compared to the consensus of five radiologists, the Ensemble4Covid model achieved an AUC of 0.85, whereas the radiologists achieved an AUC of 0.71. Compared with other state-of-the-art models, the performance of a single model of our ensemble achieved nonsignificant differences in the public dataset COVIDx. CONCLUSION: The results show that the use of images from the first clinical encounter significantly drops the detection performance of COVID-19. The performance of our Ensemble4Covid under these challenging conditions is considerably higher compared to a consensus of five radiologists. Artificial intelligence can be used for the fast diagnosis of COVID-19.

3.
Rev Esc Enferm USP ; 50 Spec: 68-73, 2016 Jun.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27384278

RESUMO

The purpose of this work was to explore: knowledge, attitudes, and beliefs regarding gynecologic cancer screening on Ecuadorian women users of primary care facilities, to identify the social representations that users of health services make about these programs and their influence on the decision to undergo a screening. An exploratory and qualitative research design was held using focus groups and in-depth interviews for data collection. A narrative content analysis of the results was conducted. Women's knowledge on gynecological cancer screening was confusing. Most frequent misconceptions related to the pap smear were: the belief that it could be useful for detecting pregnancy, ovarian cysts or infections. Most of the participants stated that the pap smear procedure is a traumatic and painful experience. Regarding to mammography women said it was used for sick woman and this procedure by itself may cause cancer. El propósito de esta investigación fue explorar los conocimientos, actitudes y creencias respecto a los programas de detección del cáncer ginecológico entre usuarias de centros de atención primaria de salud para identificar las representaciones sociales que las usuarias de los servicios de salud elaboran acerca de estos programas y de los diferentes procedimientos que comprenden. El diseño de la investigación fue exploratorio y cualitativo, mediante grupos focales y entrevistas a profundidad, con el respectivo análisis narrativo e interpretativo del contenido. Se encontró conocimiento confuso acerca de los programas de tamizaje de cáncer ginecológico y dificultades asociadas a la realización de los procedimientos. Los significados más frecuentes acerca de los programas fueron: el uso de la citología cérvico-vaginal para detectar embarazo, quistes ováricos o infecciones. La mayoría de los participantes asociaba este procedimiento con una experiencia dolorosa y traumática. Respecto al autoexamen de mamas, lo calificaron como un masaje preventivo-terapéutico y a la mamografía como peligrosa porque podría desarrollar cáncer.


Assuntos
Tomada de Decisões , Neoplasias dos Genitais Femininos/diagnóstico , Neoplasias dos Genitais Femininos/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Esfregaço Vaginal/psicologia , Detecção Precoce de Câncer , Equador , Feminino , Grupos Focais , Humanos , Mamografia/efeitos adversos , Mamografia/psicologia , Cistos Ovarianos/diagnóstico , Testes de Gravidez/psicologia , Pesquisa Qualitativa
4.
Rev. Esc. Enferm. USP ; 50(spe): 68-73, tab
Artigo em Inglês, Espanhol | LILACS, BDENF - Enfermagem | ID: lil-787800

RESUMO

The purpose of this work was to explore: knowledge, attitudes, and beliefs regarding gynecologic cancer screening on Ecuadorian women users of primary care facilities, to identify the social representations that users of health services make about these programs and their influence on the decision to undergo a screening. An exploratory and qualitative research design was held using focus groups and in-depth interviews for data collection. A narrative content analysis of the results was conducted. Women’s knowledge on gynecological cancer screening was confusing. Most frequent misconceptions related to the pap smear were: the belief that it could be useful for detecting pregnancy, ovarian cysts or infections. Most of the participants stated that the pap smear procedure is a traumatic and painful experience. Regarding to mammography women said it was used for sick woman and this procedure by itself may cause cancer.


O propósito desta investigação foi explorar os conhecimentos e crenças respeito aos programas de detecção do câncer ginecológico, entre usuárias de centros de atenção primaria de saúde, para identificar as representações sociais que as usuárias dos centros de saúde elaboram acerca de estes programas e dos diferentes procedimentos que compreendem. O desenho da investigação foi exploratório e qualitativo, mediante grupos focais e entrevistas a profundidade, com a respectiva análise narrativa e interpretativa do conteúdo. Encontrou-se conhecimento confuso acerca dos programas de tamisação de câncer ginecológico e dificuldades associadas à realização dos procedimentos. Os significados mais frequentes acerca dos programas foram o uso da citologia cérvico-vaginal para detectar gravidez, quistos ováricos ou infecções. A maioria das participantes associava este procedimento com una experiência dolorosa e traumática. Respeito ao autoexame de mamas, o identificaram como uma massagem preventiva-terapêutica e à mamografia, como perigosa porque poderia desenvolver câncer.


El propósito de esta investigación fue explorar los conocimientos, actitudes y creencias respecto a los programas de detección del cáncer ginecológico entre usuarias de centros de atención primaria de salud para identificar las representaciones sociales que las usuarias de los servicios de salud elaboran acerca de estos programas y de los diferentes procedimientos que comprenden. El diseño de la investigación fue exploratorio y cualitativo, mediante grupos focales y entrevistas a profundidad, con el respectivo análisis narrativo e interpretativo del contenido. Se encontró conocimiento confuso acerca de los programas de tamizaje de cáncer ginecológico y dificultades asociadas a la realización de los procedimientos. Los significados más frecuentes acerca de los programas fueron: el uso de la citología cérvico-vaginal para detectar embarazo, quistes ováricos o infecciones. La mayoría de los participantes asociaba este procedimiento con una experiencia dolorosa y traumática. Respecto al autoexamen de mamas, lo calificaron como un masaje preventivo-terapéutico y a la mamografía como peligrosa porque podría desarrollar cáncer.


Assuntos
Humanos , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Mamografia , Autoexame de Mama , Detecção Precoce de Câncer , Teste de Papanicolaou , Atenção Primária à Saúde , Programas de Rastreamento , Grupos Focais , Pesquisa Qualitativa
5.
Am J Pathol ; 176(3): 1323-38, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20093491

RESUMO

Central nervous system (CNS) invasion by bacteria of the genus Brucella results in an inflammatory disorder called neurobrucellosis. In this study we present in vivo and in vitro evidence that B. abortus and its lipoproteins activate the innate immunity of the CNS, eliciting an inflammatory response that leads to astrogliosis, a characteristic feature of neurobrucellosis. Intracranial injection of heat-killed B. abortus (HKBA) or outer membrane protein 19 (Omp19), a B. abortus lipoprotein model, induced astrogliosis in mouse striatum. Moreover, infection of astrocytes and microglia with B. abortus induced the secretion of interleukin (IL)-6, IL-1beta, tumor necrosis factor (TNF)-alpha, macrophage chemoattractant protein-1, and KC (CXCL1). HKBA also induced these inflammatory mediators, suggesting the involvement of a structural component of the bacterium. Accordingly, Omp19 induced the same cytokine and chemokine secretion pattern. B. abortus infection induced astrocyte, but not microglia, apoptosis. Indeed, HKBA and Omp19 elicited not only astrocyte apoptosis but also proliferation, two features observed during astrogliosis. Apoptosis induced by HKBA and L-Omp19 was completely suppressed in cells of TNF receptor p55-/- mice or when the general caspase inhibitor Z-VAD-FMK was added to cultures. Hence, TNF-alpha signaling via TNF receptor (TNFR) 1 through the coupling of caspases determines apoptosis. Our results provide proof of the principle that Brucella lipoproteins could be key virulence factors in neurobrucellosis and that astrogliosis might contribute to neurobrucellosis pathogenesis.


Assuntos
Apoptose , Astrócitos/microbiologia , Astrócitos/patologia , Brucella abortus/fisiologia , Mediadores da Inflamação/metabolismo , Animais , Antígenos de Bactérias/farmacologia , Apoptose/efeitos dos fármacos , Astrócitos/enzimologia , Astrócitos/metabolismo , Proteínas da Membrana Bacteriana Externa/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/microbiologia , Encéfalo/patologia , Brucella abortus/efeitos dos fármacos , Caspases/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quimiocinas/metabolismo , Feminino , Temperatura Alta , Imuno-Histoquímica , Lipopolissacarídeos/farmacologia , Lipoproteínas/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Microglia/efeitos dos fármacos , Microglia/microbiologia , Microglia/patologia , Fator de Necrose Tumoral alfa/metabolismo
6.
BMC Med Genet ; 3: 4, 2002 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-12033991

RESUMO

BACKGROUND: Multiple endocrine neoplasias type 2A (MEN 2A) is a dominantly inherited cancer syndrome. Missence mutations in the codon encoding cysteine 634 of the ret proto-oncogene have been found in 85% of the MEN 2A families. The main tumour type always present in MEN 2A is medullar thyroid carcinoma (MTC). Only 25% of all MTC are hereditary, and generally they are identified by a careful family history. However, some familial MTCs are not easily detected by this means and underdiagnosis of MEN 2A is suspected. METHODS: DNA samples from MEN 2A patients were amplified by PCR. The products were incubated with the restriction enzyme Bst ApI or Bgl I. The samples were loaded in non-denaturing 10% Polyacrilamyde Gel and run at 120 volts for 40 min. The gels were stained with 10 microg/ml ethidium bromide, and the bands were visualized under a UV lamp. RESULTS: We developed a PCR-mutagenic method to check the integrity of the three bases of the cysteine 634 codon. CONCLUSION: The method can be used to detect inherited mutations in MTC patients without a clear family history. The method is relatively simple to use as a routine test in these patients to decrease the underdiagnosis of MEN 2A. In addition, the assay can be used to screen affected families with any mutation in cysteine 634.

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