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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.
81

Avaliação da resposta clínica e humoral dos pacientes portadores de ICV submetidos à vacinação com antígenos protéicos e polissacarídicos / Clinical and laboratory evaluation of patients with common variable immunodeficiency before and after immunization with polysaccharide and protein antigens

Ana Karolina Barreto Berselli Marinho 14 March 2013 (has links)
Estudos recentes têm apresentado resultados in vitro satisfatórios em pacientes com Imunodeficiência Comum Variável (ICV) que receberam vacinas contra tétano, influenza e meningococo. No entanto, existem poucos ensaios clínicos que avaliem a resposta clínica e laboratorial após a exposição a antígenos específicos. O presente estudo tem como objetivo avaliar a resposta clínica à imunização contra antígenos protéicos e polissacarídicos (influenza, H1N1 e pneumococo) em pacientes com diagnóstico de ICV seguidos no ambulatório de Imunodeficiências Primárias do Serviço de Imunologia Clínica e Alergia do HC-FMUSP. O diagnóstico dos pacientes foi estabelecido de acordo com os critérios da OMS / PAGID / ESID. Um grupo de 37 pacientes foi vacinado contra a influenza A (H2N3), gripe H1N1 e pneumococo e outro grupo com 16 pacientes, não foi vacinado. A avaliação clínica foi realizada através da aplicação de um score com avaliação dos seguintes parâmetros clínicos: pneumonia, sinusite, otite média, infecções de vias aéreas superiores (IVAS), amigdalites, diarréia, bronquiectasias, hospitalizações, uso de antibióticos, uso de antibióticos profiláticos, sepse e meningite. O score foi aplicado durante os 12 meses que precederam a vacinação e 12 meses posteriores à administração das vacinas. O mesmo score foi aplicado ao grupo controle, com os pacientes que não foram vacinados. A determinação da IgG contra os sorotipos do pneumococo foi feita por ELISA. A determinação da IgG específica H1N1 foi feita por hemaglutinação indireta, enquanto que a dosagem da IgG específica para influenza, por ELISA, utilizando o kit comercial RIDASCREEN ® Influenza. O grupo de pacientes vacinados incluiu 37 pacientes (51% mulheres), com idade entre 20 e 78 anos (mediana= 33 anos). Observou-se uma mediana de 7 anos de atraso no diagnóstico de ICV. A mediana de idade do grupo de pacientes (n=16, 37,5% mulheres) que não receberam a vacina foi de 41 anos e a mediana de atraso no diagnóstico foi de 8 anos. Observamos que as infecções de vias aéreas superiores (IVAS), sinusites e pneumonias foram as manifestações mais freqüentes no grupo controle. IVAS seguida por pneumonia e sinusite foram as manifestações infecciosas mais freqüentes em mulheres (80%, 78% e 55%, respectivamente). Entretanto, em homens observamos IVAS seguido por sinusite e pneumonia (78%, 65% e 35%, respectivamente). Observou-se redução significativa no score relativo ao número de infecções respiratórias superiores, sinusites e pneumonias um ano após a administração das vacinas (p <0,001). Os dados foram comparados com pacientes ICV não vacinados e neste grupo não houve diferença entre os scores dos dois períodos de 12 meses . Após a vacinação, observou-se uma tendência a aumento no título de anticorpos específicos para a H2N3, mas sem resultado significativo. Em relação aos resultados obtidos com as sorologias para o H1N1 e o pneumococo, não se observou resposta após a vacinação. Concluindo, houve redução do número de infecções, principalmente das IVAS, sinusites e pneumonias em pacientes com ICV após a vacinação contra a influenza, H1N1 e pneumococo. Embora não tenhamos encontrado correlação entre a redução do número de infecções e os títulos de anticorpos específicos para as vacinas testadas, a melhora clínica observada nos pacientes com ICV reforça o benefício da vacinação / Recent studies have shown satisfactory in vitro results in patients with CVID who received immunization against tetanus, influenza and meningococcus. However, there are only a few studies that evaluate the clinical and laboratory response after exposure to specific antigens in these patients. This study aims to evaluate the clinical response to immunization with protein and polysaccharide antigens (influenza, H1N1 and pneumococcus) in CVID patients followed at the Primary Immunodeficiency outpatient clinic of the Division of Clinical Immunology and Allergy, Hospital das Clínicas, FMUSP. CVID patients were diagnosed according the WHO/PAGID/ ESID criteria. Thirty-seven patients were immunized against influenza (H2N3), H1N1 and pneumococcal polysaccharide vaccine while another group with 16 CVID patients were not vaccinated. Clinical evaluation was performed through a score with assessment of the following parameters: pneumonia, sinusitis, otitis media, upper respiratory infections (URI), tonsillitis, diarrhea, bronchiectasis, hospitalizations, use of antibiotic therapy, and use of prophylactic antibiotics, sepsis and meningitis. The score was applied during the 12 months prior to immunization and one year after the administration of vaccines. The same score was applied to the group of CVID patients who weren´t immunized. Determination of IgG antibodies to pneumococcal serotypes was made by ELISA. H1N1-specific IgG was detected by indirect hemagglutination while the determination of influenzaspecific IgG was performed by ELISA, using the RIDASCREEN ® Influenza kit. The group of patients who were vaccinated included 37 patients (51% women), aged 20 to 78 years (mean 33 years). This group presented a median delay in the diagnosis of 7 years. The control group consisted of 16 patients (37.5% females) who were not immunized. Their median age was 41 years and the median delay in the diagnosis was 8 years. URI followed by pneumonia and sinusitis were the most frequent infections in women (80%, 78% and 55% respectively). However in men, URI followed by sinusitis and pneumonia were the most frequent (78%, 65% and 35% respectively). We observed a significant reduction in the score of URI, sinusitis and pneumonias in the year post administration of the vaccines (p <0.001). Conversely, there was no difference in the infections pre and post supposed vaccination scores in the group of CVID patients who were not immunized. There was no significant change in specific antibody titers to influenza and pneumococcus after vaccination. Regarding H1N1, there was no statistically significant production of antibodies to H1N1, although we observed a slight non-durable increase in antibody titers. In conclusion, there was a reduction in the number of infections, mainly sinusitis, URIs and pneumonias in patients with CVID vaccinated against influenza, H1N1 and pneumococcus. While we found no correlation between the reduction in the number of infections and specific antibody titers for the vaccines administered, the clinical improvement observed in CVID patients reinforces the benefit of vaccination
82

Efeito antinociceptivo do HC-030031, um antagonista seletivo do receptor de potencial transitÃrio anquirina subtipo 1 (TRPA1), em modelos de nocicepÃÃo visceral. / Antinociceptive effect of HC-030031, a selective antagonist of transient receptor potential ankirin subtype 1 (TRPA1), on experimental models of visceral nociception.

Lus Mario da Silva Pereira 12 August 2012 (has links)
A famÃlia de receptores de potencial transitÃrio (TRP) incluindo o receptor de potencial transitÃrio anquirina, subtipo 1 (TRPA1) tem mostrado ser um alvo terapÃutico potencial para o tratamento da dor aguda e crÃnica. Alguns estudos tÃm demonstrado que a resposta nociceptiva somÃtica se deve à ativaÃÃo dos receptores TRPA1 e sÃo efetivamente modulados atravÃs da ferramenta experimental, HC-030031, um antagonista seletivo. Contudo, existem poucos estudos que avaliam o papel dos receptores TRPA1 na dor visceral. Portanto, investigamos o papel do TRPA1 em modelos animais de nocicepÃÃo visceral induzido por diferentes substÃncias e tambÃm exploramos os possÃveis mecanismos envolvidos. Camundongos Swiss, machos (N=6) receberam carboximetilcelulose 0,5% (veÃculo CMC 0,5%, 1 mL/Kg, v.o.), HC-030031 (75, 150 ou 300 mg/Kg, v.o.), ou L-NAME (10 e 40 mg/Kg, s.c.) ou somente L-Arginina (600 mg/Kg, i.p.), 1 h apÃs foi administrado uma Ãnica injeÃÃo de IFO (400 mg/Kg, i.p.). A nocicepÃÃo visceral foi avaliada atravÃs do teste de Von Frey eletrÃnico previamente (T0) e 12 h (T1) apÃs a injeÃÃo de IFO com estimulaÃÃo abdominal atravÃs de um analgesÃmetro digital. Os resultados foram obtidos em gramas (T0-T1) pela variaÃÃo da hiperalgesia. Em seguida as bexigas dos animais foram removidas para pesagem, anÃlise e foram atribuÃdos escores macro e microscopicamente. Investigou-se, tambÃm, o efeito antinociceptivo visceral do HC-030031 atravÃs do modelo de nocicepÃÃo visceral induzido por Ãleo de mostarda (OM). Os animais foram tratados com CMC 0,5%, HC-030031 (18,75; 37,5 ou 75 mg/kg, v.o.) ou Morfina (5 mg/Kg, s.c.) isoladamente ou receberam Naloxona (2 mg/Kg, i.p.) previamente a estas drogas. Em seguida, OM 0,75% (50 &#956;L/colon) foi instilado localmente no cÃlon. A nocicepÃÃo visceral foi verificada atravÃs do teste de Von Frey previamente (T0) e 10 min. (T1) apÃs a injeÃÃo do OM. Em outro protocolo experimental, os animais foram tratados com CMC 0,5% (10 mL/kg, v.o.) ou HC-030031 (18,75; 37,5 ou 75 mg/Kg, v.o.) previamente a uma injeÃÃo intraperitoneal com Ãcido acÃtico 0,6% (AA, 10 mL/Kg,), zymosan (Zym, 1 mg/cavidade) ou misoprostol (MPT, 1 Âg/cavidade, um anÃlogo estÃvel de prostaglandinas). Imediatamente apÃs a injeÃÃo desses algogÃnicos, contabilizaram-se as contorÃÃes abdominais por 30 min. Adicionalmente, para investigar o papel de cÃlulas peritoneais residentes sobre o efeito do HC-030031, a cavidade peritoneal dos camundongos foi lavada com uma soluÃÃo de 30 mL (PBS + heparina) e os estÃmulos AA, Zym e MPT foram injetados i.p. Um grupo Sham foi incluÃdo tambÃm neste protocolo. Ao final do experimento, as contorÃÃes abominais foram registradas por 30 mim. Utilizou-se para a anÃlise estatÃstica, ANOVA/Student e Newman/Keul, foi considerado significativo um p < 0,05 (CEPA: Protocolo: 92/10). A IFO induziu significativa (p<0,05) nocicepÃÃo visceral (6,25Â1,08) e resposta inflamatÃria [escores edema 2(1-3); hemorragia 3(1-3) e peso bexiga (42,78 3,10)] comparado com o grupo salina (1,97Â0,89),[ 0(0-0); 0(0-0) e 20,01 0,7749] respectivamente. AlÃm disso, HC-030031(75 mg/Kg) e L-NAME (10 e 40 mg/Kg) preveniram de maneira significativa (p<0,05) da resposta nociceptiva (2,30Â1,07; 1,58Â0,86 e 0,2500  0,73) respectivamente quando comparado com o grupo IFO. O prÃ-tratamento com L-Arginina (6,844Â1,235) reverteu o efeito antinociceptivo do L-NAME 10 mg/Kg, (6,84Â1,23), mas foi ineficaz sobre o efeito do L-NAME 40 mg/Kg (1,500Â0,7361) e HC-030031 75 mg/Kg (0,7200Â0,6953). Contudo, o prÃ-tratamento com HC-030031 nÃo apresentou efeito antiinflamatÃrio. Adicionalmente, verificou-se que o OM induziu significativo (p<0,05) comportamento nociceptivo (6,333Â0,9458) quando comparado ao grupo salina (1,250Â0,9204). AlÃm disso, o HC-030031 preveniu de maneira significativa da resposta nociceptiva provocada pelo OM (1,536 Â0,7653). Avaliou-se tambÃm o envolvimento do sistema opiÃide no efeito antinociceptivo do HC-030031. Verificou-se que a morfina apresentou uma importante atividade antinociceptiva (0,07143Â0,07143) contra a nocicepÃÃo induzida por OM a qual foi significativamente revertida pelo prÃ-tratamento com naloxona (3,125 1,302). Por outro lado, o efeito antinociceptivo do HC-030031 nÃo foi afetado pela naloxona (2,240Â1,263). Adicionalmente, AA, Zym e MPT induziram respostas de contorÃÃes abdominais significativas (43,71Â4,43; 11,00Â2,11 e 9,00Â2.30, respectivamente) as quais foram significativamente inibidas com HC-030031 (18,75, 37,5 ou 75 mg/kg, v.o.) em todas as doses utilizadas no teste com AA (29,07%; 53,35% e 41,59%), no teste com Zym (55,85%; 61,03% e 71,20%) e no teste com MPT (63,88%; 83,33% e 88,88%). Uma vez que a prostaglandina ativa o nociceptor diretamente, demonstrou-se que o HC-030031 possivelmente inibe a nocicepÃÃo visceral atravÃs da estabilizaÃÃo direta de nociceptores. O efeito antinociceptivo do HC-030031 parece ser independente da inibiÃÃo de cÃlulas residentes inflamatÃrias, do Ãxido nÃtrico ou do sistema opiÃide. Este estudo fornece perspectivas para o manuseio da dor visceral atravÃs da modulaÃÃo dos canais TRPA1. / The description of the TRP family of receptors including TRPA1 has provided potential therapeutic targets for treating acute and chronic pain. Some studies have shown a somatic nociceptive response due to the TRPA1 receptors activation which is effectively modulated with the experimental tool, HC-030031, a TRPA1 antagonist. However, there are a few studies evaluating the role of TRPA1 receptors in visceral pain. Then aimed to investigate the role of TRPA1 in the animal models of visceral nociception induced by different substances and to explore the possible mechanisms involved. Swiss male mice (n=6) were given only Carboxymethyl cellulose (vehicle CMC 0.5%, 1 mL/kg, p.o.), the compound HC-030031 (75, 150 or 300 mg/Kg, p.o.) or L-NAME (10 or 40 mg/Kg, s.c.) alone or with L-arginine (600mg/Kg, i.p.) 1h previously a alone injection of IFO (400 mg/kg, i.p.). Visceral nociception was assessed through the von Frey test previously (T0) and 12h (T1) later IFO injection by the abdominal stimulation with a pressure meter. The results were obtained in grams (T0-T1). The bladder of these animals were also removed to weighted (BWW), analyzed and after given scores macro and microscopically. We also investigated the antinociceptive effect of HC-030031 in the model of mustard oil-induced visceral nociception. The animals were treated with CMC 0.5% or HC-030031 (18.75, 37,5 or 75 mg/kg) or Morphine (5 mg/Kg, s.c.) alone or with Naloxone (2 mg/Kg, i.p.) 1h previously the injection of Mustard oil (MO) 0,75% (MO, 50 ul/colon). Visceral nociception was assessed through the von Frey test previously (T0) and 10 min (T1) after MO injection by the abdominal stimulation with a pressure meter. The results were obtained in grams (T0-T1). In another experimental setting, the animals were treated with CMC 0.5% (1 mL/kg, p.o) or HC-030031 (18.75; 37.5 or 75mg/Kg, p.o.) previously an intraperitoneal injection with acetic acid 0.6% (AA, 10 mL/kg), zymosan (Zym, 1 mg/cavity) or misoprostol (MPT, a stable prostaglandin analogous, 1&#956;g/cavity) and immediately had the writhing responses counted for 30 min. In order to investigate the role of resident peritoneal cells on the effect of HC-030031, we washed the peritoneal cavity of mice with heparin added PBS (30 mL) and then AA, Zym or MPT were injected i.p. A Sham group was included. Eventually, the writhing responses were recorded. Statistical analysis was performed with ANOVA/Student Newman Keul as appropriate. p<0.05 was accepted. (CEPA: Protocol 92/10). IFO induced significant (p<0.05) visceral nociception (6.25Â1.08) and inflammatory response [scores to edema 2(1-3); hemorrhage 3(1-3); and bladder wet weight (42.78  3.1)] in comparison with saline treated group (1.97Â0.89), [0(0-0); 0(0-0); 20.01 0.7749] respectively. Moreover, HC-030031(75) and L-NAME (10 or 40 mg/Kg) prevented in a significant manner (p<0.05) the nociceptive response (2.30Â1.07; 1.58Â0.860 and 2500Â0.7361) respectively when compared with IFO-treated group. Although the pretreatment with L-arginine (6.844Â1.235) was able to reverse the antinoceceptive effect of L-NAME 10 mg/Kg, (6.84Â1.23), it failed to do the same (p>0.05) with L-NAME 40 mg/Kg (1.500Â0.7361) and HC-0300031 75 mg/Kg (0.72Â0.69). The same reversible effect of L-Arginine was observed for the anti-inflammatory activity of L-NAME (p<0.05). However, HC-030031 presented no anti-inflammatory effect. The antinociceptive activity of HC-030031 was also assessed in the MO nociception model. We verified that MO induced a significant (p<0.05) nociceptive behavior (6.333Â0.9458) when compared to saline injected mice (1.250Â0.9204). Moreover, HC-030031 prevented in a significant manner the nociceptive response elicited by MO (1.536Â0.7653). Furthermore, the involvement of opioid system in the antinociceptive effect of HC-030031 as tested. We observed that morphine presented an important antinociceptive activity (0.07143Â0.07143) against MO-induced nociception which was significantly reverted by naloxone pre-treatment (3.125 1.302). On the other hand, the antinociceptive effect of HC-030031 remained in spite the injection of naloxone (2.240Â1.263). In addition to that, AA, Zym and MPT induced significant writhing responses (43.71Â4.43; 11.00Â2.11; 9.00Â2.30; respectively) which was significantly inhibited with HC-030031(18.75, 37.5 e 75 mg/kg, p.o.) treated mice in all the doses tested (29.07%, 53.35% and 41.59%, in the AA test, 55.85%, 61.03% and 71.20%, in the Zym test, 63.88%, 83.33% and 88.88%, in the MPT induced nociception, respectively to 18.75, 37.5 and 75 mg/kg doses. Eventually, the reduction of cell population in the peritoneal cavity prevented the development of writhing responses in both AA and Zym injected mice, with no effect was visualized on MPT treated mice. We the conclude that, since prostaglandin activates the nociceptor directly, it was shown that HC-030031 inhibits visceral nociception possibly through the stabilization of the neuronal ends. The antinociceptive effect of HC-030031 seems to be independent of the inhibition of inflammatory resident cells, opioid and nitric oxide pathways. This study provides perspective for the effective management of visceral pain through the modulation of TRPA1 channels.
83

Estudo epidemiológico da infecção pelo vírus da imunodeficiência felina em gatos domésticos da região sul do Rio Grande do Sul / Epidemiological study of the feline immunodeficiency virus infection in domestic cats of the south region of Rio Grande do Sul State

SILVA, Fábio da Silva e 24 February 2012 (has links)
Made available in DSpace on 2014-08-20T14:37:48Z (GMT). No. of bitstreams: 1 Dissertacao_fabio_silva.pdf: 518189 bytes, checksum: 5328c1b56ef14ad739bd14cb751dcd72 (MD5) Previous issue date: 2012-02-24 / The feline immunodeficiency virus belongs to the Retroviridae family, Lentivirus gennus and presents molecular structure and pathogenicity similar to the human immunodeficiency virus (HIV), therefore it is not transmissible to humans, being susceptible only the domestic and feral cats. FIV is classified in five phylogenetically different subtypes from A to E spread worldwide, apart from recombinant strains among the subtypes. Recently, two new subtypes were described, the subtype F identified in the United States and Portugal, and the subtype U-NZenv in New Zealand. Considering that the retroviruses have the ability to integrate the cell genome, under double stranded DNA form, it is possible to detect the provirus in infected leucocytes through the polymerase chain reaction (PCR) technique. The present report investigated the occurrence of the feline immunodeficiency virus infection between 2010 and 2011 in domestic cats submitted to medical treatment at the Hospital of Veterinary Clinics of the Federal University of Pelotas and private clinics from Pelotas, RS. Blood samples of seventy animals, healthy or sick, were collected and subjected to the nested-PCR technique. The tested cats were classified in two groups taking into account their clinical condition: the group 1 represented 28 FIV suspect cats with lymphadenomegaly, neurological disorders or chronic and recurring infections. The results pointed out a FIV infection frequency of 15,7% (11/70). Eight of the positive samples were subjected to molecular characterization, being all of them into the subtype B. The most diagnosed clinical manifestations in the cats that developed disease related to FIV were bronchopulmonar (4/10) and cutaneous (3/10) secondary infections. Another clinical disorders observed in the positive animals were gingivitis, uveitis, anemia and icterus. The FIV infected cats presented 30% of lethality during the period of study. Most of the infected cats were up to 10 years of age. Faced with the data shown in this report we could conclude that the subtype B of the feline immunodeficiency virus presents circulation in the domestic cat population of the south region of Rio Grande do Sul and elderly animals affected by chronic or recurring infections must be FIV tested. / O vírus da imunodeficiência felina pertence à família Retroviridae, gênero Lentivirus e apresenta estrutura molecular e patogenia similar ao vírus da imunodeficiência humana (HIV), entretanto não é transmissível ao homem, sendo suscetíveis somente os felinos domésticos e selvagens. O FIV é classificado em cinco subtipos filogeneticamente diferentes de A a E, distribuídos mundialmente, além de cepas com recombinações entre os subtipos. Recentemente dois novos subtipos foram descritos, o subtipo F identificado nos Estados Unidos e Portugal, e o subtipo U-NZenv na Nova Zelândia. Considerando-se que os retrovírus têm a capacidade de integrar-se ao genoma celular, sob a forma de DNA de dupla fita, é possível a detecção do provírus em leucócitos infectados, através da técnica de reação em cadeia da polimerase (PCR). O presente trabalho investigou a ocorrência de infecção pelo vírus da imunodeficiência felina, entre os anos de 2010 e 2011, em gatos domésticos levados para atendimento médico no Hospital de Clínicas Veterinária da Universidade Federal de Pelotas e clínicas privadas da cidade de Pelotas, RS. Amostras de sangue de 70 animais, entre hígidos e doentes, foram colhidas e submetidas à técnica de nested-PCR. Os gatos testados foram classificados em dois grupos quanto à condição clínica: o grupo 1 foi representado por 28 felinos suspeitos de FIV, diagnosticados com linfoadenomegalia, sinais neurológicos ou com infecções crônicas e recidivantes; o grupo 2 representado por 42 animais livres de sintomatologia relacionada a FIV. Os resultados apontaram uma frequência de infecção pelo FIV de 15,7% (11/70). Das amostras positivas, 8 foram submetidas à caracterização molecular, sendo todas alocadas dentro do subtipo B. As manifestações clínicas mais diagnosticadas nos felinos que desenvolveram doença relacionada a FIV, foram as infecções secundárias broncopulmonares (4/10) e cutâneas (3/10). Outras alterações clínicas identificadas em animais positivos foram gengivite, uveíte, anemia e icterícia. Os animais infectados por FIV apresentaram letalidade de 30% durante o período de estudo. Em relação à faixa etária a maior proporção de felinos infectados apresentava idade superior a 10 anos. Diante dos dados apresentados conclui-se que o subtipo B do vírus da imunodeficiência felina apresenta circulação na população de gatos domésticos da região sul do Rio Grande do Sul, e que animais idosos acometidos por infecções crônicas ou recidivantes devem ser testados para esse agente.
84

Morbidade materna grave por infecção e influenza H1N1 na Rede Brasileira de Vigilância de Morbidade Materna Grave = Severe maternal morbidity due to infection in the Brazilian Network for the Surveillance of Severe Maternal Morbidity / Severe maternal morbidity due to infection in the Brazilian Network for the Surveillance of Severe Maternal Morbidity

Pfitscher, Lúcia Chaves, 1981- 28 August 2018 (has links)
Orientadores: Maria Laura Costa do Nascimento, José Guilherme Cecatti / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-28T01:47:22Z (GMT). No. of bitstreams: 1 Pfitscher_LuciaChaves_M.pdf: 6366056 bytes, checksum: 9a70e9992cbec443ea7d924bdc77f7bb (MD5) Previous issue date: 2015 / Resumo: Introdução: A infecção representa importante causa de morbidade e mortalidade materna, sendo uma preocupação crescente no mundo todo. As doenças respiratórias, especialmente as virais, têm se destacado justamente pelo potencial de epidemia com que ameaçam a saúde da população mundial e pela vulnerabilidade identificada durante a gestação. Objetivo: Avaliar o impacto da morbidade materna grave (MMG) atribuível à infecção (sepse, meningite e doença respiratória) e os fatores associados ao pior resultado materno (near miss e óbito), entre mulheres da Rede Brasileira de Vigilância da Morbidade Materna Grave. Métodos: análise secundária de um estudo transversal, multicêntrico, que incluiu 27 centros de referência obstétrica das cinco regiões do Brasil no período de 2009 e 2010. A vigilância prospectiva dos casos de infecção grave foi realizada utilizando os critérios da OMS de condições potencialmente ameaçadoras da vida (CPAV) e near miss materno (NMM). Os principais focos de infecção foram identificados e comparados a outras causas de MMG. Mulheres com complicação devido à doença respiratória também foram avaliadas em dois grupos: com e sem suspeita de A(H1N1)pdm09 e também comparadas a outras causas de MMG. Casos com suspeita de A(H1N1)pdm09 foram revisados e separados em três grupos: não-testados, confirmados e não confirmados para A(H1N1)pdm09 e os seus resultados foram comparados. Complicações devidas à infecção e a doenças respiratórias foram comparadas com complicações devidas a outras causas de MMG. Os fatores associados com desfecho materno grave (DMG) foram avaliados para os casos de infecção e doença respiratória. Resultados: Dentre os 9555 casos de MMG, apenas 502 (5,3%) apresentaram infecção grave, entretanto foram responsáveis por cerca de um quarto dos casos de NMM e quase metade dos casos de morte materna (MM). Os indicadores de saúde avaliados demonstram maior gravidade dos casos complicados por infecção, com índice de mortalidade (IM) superior a 26% em comparação com 11% para as demais causas de MMG. Para doença respiratória, 206 mulheres apresentaram suspeita de A(H1N1)pdm09, cerca de 60% foram testados para a doença e 49 mulheres apresentaram resultado positivo. A gravidade dos desfechos maternos foi pior entre os casos de A(H1N1)pdm09 positivo, com uma taxa de NMM:MM abaixo de 1 (0,9:1), em comparação a 12:1 para outras causas de MMG. O IM para doença respiratória foi superior a 50% (7,4% outras causas de MMG). Demoras no atendimento foram associadas com pior prognóstico materno e estiveram presentes em mais de 50% entre os casos de infecção, aumentando em duas vezes o risco de DMG para doença respiratória. Resultados perinatais foram piores dentre os casos de doença respiratória, com aumento da prematuridade, morte fetal, baixo peso ao nascer e Apgar <7. HIV/AIDS, histerectomia, hospitalização prolongada, admissão em UTI e demoras no atendimento foram alguns fatores independentes associados DMG. Conclusão: complicações por infecção e em especial por influenza A(H1N1)pdm09 geram grande impacto sobre morbidade e mortalidade materna no Brasil e compreender os fatores associados à maior gravidade pode gerar medidas capazes de colaborar para a melhoria do cuidado obstétrico. Investir em intervenções específicas para gravidez, visando diagnóstico precoce e tratamento oportuno são essenciais para melhorar a saúde materna e reduzir o número de mortes maternas evitáveis no país / Abstract: Background: Infection represents the major cause of maternal morbidity and mortality, and a growing concern worldwide. Respiratory diseases, especially viral, have stood out because of their epidemic potential and the identified vulnerability towards infection during pregnancy. Objective: To assess the impact of severe maternal morbidity (SMM) due to infection (sepsis, meningitis and respiratory disease) and the factors associated with worse maternal outcome (near miss and death) among women of the Brazilian Network for the Surveillance of Severe Maternal Morbidity. Methods: secondary analysis of a cross-sectional, multicenter study that included 27 obstetric referral centers in five regions of Brazil between 2009 and 2010. Prospective surveillance of severe infection was performed using WHO criteria of potentially life threatening conditions (PLTC) and maternal near miss (MNM). The main sources of infection were identified and compared to other causes of SMM. Women with complications due to respiratory disease were also assessed in two groups: with and without suspected A(H1N1)pdm09 and also compared to other causes of SMM. Cases of suspected A(H1N1)pdm09 were reviewed and divided into three groups: non-tested, confirmed and unconfirmed for A(H1N1)pdm09 and their results were compared. Complications due to infection and respiratory disease were compared with complications due to other causes of SMM. Factors associated with SMO were assessed for cases of infection and respiratory disease. Results: Among the 9555 cases of SMM, only 502 (5.3%) had severe infection, however they were responsible for about a quarter of cases of MNM and almost half of the cases of maternal mortality (MM). The assessed health indicators demonstrate greater severity of cases complicated by infection, with a mortality index (MI) above 26% compared to 11% for other causes of SMM. For respiratory disease, 206 women had suspected A(H1N1)pdm09, about 60% were tested for the disease and 49 women were positive. The severity of the maternal outcomes was worse between the cases of A(H1N1)pdm09 positive, with a rate of MNM: MM below 1 (0.9: 1), compared to 12: 1 for other SMM causes. The MI among respiratory disease was superior to 50% (7.4% other causes SMM). Delays in care were associated with worse maternal prognosis and were present in over 50% of cases of infection. Perinatal results were worse in cases of respiratory disease, with increased prematurity, stillbirth, low birth weight and Apgar <7. HIV/AIDS, hysterectomy, prolonged hospitalization, ICU admission and delays in care were independent factors associated with severe maternal outcome. Conclusion: infections and especially those caused by A(H1N1)pdm09 presented great impact on maternal morbidity and mortality in Brazil and the identification of factors associated with the increased severity can contribute to the improvement of obstetric care. There is need for specific interventions during pregnancy, seeking early diagnosis and timely treatment of infections, which are essential for improving maternal health and to reducing the number of preventable maternal deaths in the country / Mestrado / Saúde Materna e Perinatal / Mestra em Ciências da Saúde
85

Specific cognitive–neurophysiological processes predict impulsivity in the childhood attention-deficit: hyperactivity disorder combined subtype

Bluschke, A., Roessner, V., Beste, C. 04 June 2020 (has links)
Background. Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent neuropsychiatric disorders in childhood. Besides inattention and hyperactivity, impulsivity is the third core symptom leading to diverse and serious problems. However, the neuronal mechanisms underlying impulsivity in ADHD are still not fully understood. This is all the more the case when patients with the ADHD combined subtype (ADHD-C) are considered who are characterized by both symptoms of inattention and hyperactivity/impulsivity. Method. Combining high-density electroencephalography (EEG) recordings with source localization analyses, we examined what information processing stages are dysfunctional in ADHD-C (n = 20) compared with controls (n = 18). Results. Patients with ADHD-C made more impulsive errors in a Go/No-go task than healthy controls. Neurophysiologically, different subprocesses from perceptual gating to attentional selection, resource allocation and response selection processes are altered in this patient group. Perceptual gating, stimulus-driven attention selection and resource allocation processes were more pronounced in ADHD-C, are related to activation differences in parieto-occipital networks and suggest attentional filtering deficits. However, only response selection processes, associated with medial prefrontal networks, predicted impulsive errors in ADHD-C. Conclusions. Although the clinical picture of ADHD-C is complex and a multitude of processing steps are altered, only a subset of processes seems to directly modulate impulsive behaviour. The present findings improve the understanding of mechanisms underlying impulsivity in patients with ADHD-C and might help to refine treatment algorithms focusing on impulsivity.
86

Detection and characterization of Human Herpes Virus -8 in an HIV-infected cohort in Cameroon

Alayande, Doyinmola Paul 18 May 2017 (has links)
MSc (Microbiology) / Department of Microbiology / Background: Human Herpes Virus-8 (HHV-8) and Human Immunodeficiency Virus (HIV) are endemic in sub-Saharan Africa. However, the prevalence of HHV-8 in HIV-infected individuals in sub-Saharan Africa has not been fully described and characterized. Objectives: The objective of this study was to determine the seroprevalence and genetic subtypes of HHV-8 in an HIV-infected population in Cameroon. Methodology: KSHV/HHV-8 Enzyme-linked Immunosorbent Assay (ELISA) kit (Advanced Biotechnologies Inc., USA) was used to detect IgG antibodies in the plasma of 406 HIV-infected outpatients of the Mutengene Baptist Health Centre, Cameroon. To detect the viral presence, a 233 bp fragment of the ORF 26 gene of HHV-8 was targeted by polymerase chain reaction (PCR) in total DNA purified from patients’ whole blood. A 453 bp of the K1 gene was amplified by nested PCR, sequenced and phylogenetically analysed to infer subtypes. The online tool, Synonymous Non-synonymous Analysis Program (SNAP), was used to determine the rate of synonymous and nonsynonymous mutations in the K1 gene. The genetic variability among the derived K1 nucleotide sequences was determined by mean genetic distance analysis. Results: Of the 406 participants, an HHV-8 seroprevalence of 79.1% was obtained. There was a statistically significant association of seroprevalence with age (p= 0.00), CD4+ cell count (p= 0.02), marital status (p= 0.02) and ownership of a transistor radio set (p= 0.00). Seventy samples (23.3%) were successfully amplified for ORF 26 gene confirming the presence of replicating virus. K1 sequences were obtained for 14 of the 20 (70%) K1 amplified DNAs. The mean genetic diversity of K1 sequences ranges from 0.0%-22.3%. Phylogenetic analysis revealed two infecting viral subtypes in the study cohort: subtype A5 (57.1%), and subtype B (35.7%). Greater positive selection and genetic diversity were observed in A5 subtype compared to B subtype of K1. Interestingly, one sample (BM 547) clustered with an unclassifiable sequence from South Africa. Conclusions and recommendation: This study revealed the endemicity of HHV-8 infection in the studied population, with subtypes A5 and B as the most important epidemiological genetic variants. In addition, targeting the ORF 26 region by PCR could be an approach to detect replicating virus in individuals. Further studies should investigate the association between HHV-8 infection and KS development in the study area which is endemic for HIV. This study contributes data to the HIV/HHV-8 co-infection landscape in the study area and in Africa at large.
87

Overexpression and structure-function characterization of HIV-1 Subtype C. reverse transcriptase and protease

Tambani, Tshifhiwa 20 September 2019 (has links)
PhD (Microbiology) / Department of Microbiology / High genetic diversity is a major contributory factor in the development of drug resistance, in addition to challenges in diagnosis and treatment monitoring in the therapeutics of human immunodeficiency virus (HIV) .Within the wide HIV-1 diversity, differences in mutational frequency, disease progression, drug response and transmission amongst HIV-1 subtypes have been shown. In spite HIV-1 subtype C (HIV-1C) being the most prevalent variant globally, none of the available drugs nor screening assays for inhibitory molecules have been developed targeting the genetics of this important subtype. This study therefore aimed to overexpress and biophysically characterize HIV-1C reverse transcriptase and protease to serve as reagents in the development of assays for routine screening of molecules inhibitory to HIV-1C. Heterologous expression of HIV-1C reverse transcriptase and protease isolates that are prevalent in South Africa was carried out in Escherichia coli (E. coli (BL21-DE3). The secondary and tertiary structures of the proteins were determined using, circular dichroism (CD) and fluorescence spectroscopy respectively. Thereafter, interaction studies to delineate interaction properties of natural products for possible inhibition of protease were conducted. Furthermore, in silico studies to determine binding interactions, further confirmed by in vitro binding assays of a pepsin inhibitor homolog (Bm-33) from Brugia malayi , against protease were also conducted. Expressed reverse transcriptase and protease from the globally prevalent HIV-1C were shown to be structurally and functionally intact for application in downstream HIV-1 inhibition assays. Interaction studies on the other hand revealed successful inhibition of the expressed HIV-1C PR with gallotanin. Furthermore, binding interactions of Bm-33 and HIV-1 PR revealed the first intermolecular interactions of the two molecules displaying possible inhibition of HIV-1 PR / NRF
88

A Population-Based Epidemiological Description of Socio-Demographic Characteristics and Predictors of Severity Among Hospitalized 2009 H1N1 Influenza Cases in Massachusetts: A Dissertation

Placzek, Hilary 23 February 2012 (has links)
The spread of pandemic influenza A (2009 H1N1 influenza) virus resulted in a global influenza pandemic in 2009. During the early stages of the pandemic, population surveillance was crucial. However, officials around the world realized that many of our surveillance and reporting systems were not prepared to respond in a coordinated, integrated way, which made informed public health decision-making very difficult. More accurate estimates of the total number of hospitalized 2009 H1N1 influenza cases were required to calculate population-based 2009 H1N1 influenza-associated mortality, morbidity and hospitalization rates. For instance, how many people were hospitalized with 2009 H1N1 influenza in Massachusetts? Of these, how many were admitted to the ICU and how many died? Compared to seasonal influenza, were some race/ethnic and age groups affected more than others, and what types of characteristics led to more severe manifestations of 2009 H1N1 influenza among these groups in Massachusetts? To address the above questions, I proposed a retrospective cohort study using data from the Hospital Discharge Database (HDD), which contains data for all inpatients discharged from 76 acute care hospitals in Massachusetts, as well as Census information to provide a measure of socioeconomic status (SES). My specific aims are as follows: 1. Develop methods to identify influenza cases precisely and describe characteristics of those hospitalized with ILI in MA between April 26-Sept 30, 2009; 2. Conduct analyses to identify race/ethnicity-related trends in reference to 2009 H1N1 influenza-related hospitalizations; 3. Conduct analyses to identify age-related trends in reference to 2009 H1N1 influenza-related hospitalizations. First, I established influenza case selection criteria using hospital discharge data. I addressed limitations in the published methods on defining cases of influenza using administrative databases, and evaluated ICD-9 codes that correspond with common and relatively serious respiratory infections and influenza using a ‘maximum’ and ‘minimum’ approach. Results confirmed that 2009 H1N1 influenza affected a younger population, and disproportionately affected racial minorities in Massachusetts. There were also higher rates of ICU admission compared to seasonal influenza. I then presented epidemiological data indicating race/ethnic disparity among 2009 H1N1 influenza cases in Massachusetts. I found that Hispanics had significantly lower odds of 2009 H1N1 influenza-related ICU stay. SES gradients calculated using five-digit zip code information did not account for these differences. Within race/ethnic strata, Hispanics Finally, I presented epidemiological data indicating differences among 2009 H1N1 influenza cases by age group in Massachusetts. I calculated measures of Diagnostic Cost Group (DxCG) comorbidity for the study population to provide a comorbidity measure at baseline. Main results indicate that although comorbidity scores were similar between the 2009 H1N1 influenza and seasonal influenza groups, 2009 H1N1 influenza caused more severe disease in younger age groups. This is the first study to report population-based statewide outcomes in all acute care centers in MA. In this dissertation I address challenges surrounding influenza surveillance to create case selection criteria within an administrative database. Using my case selection criteria, I then provide data related to fatality and severity of 2009 H1N1 influenza in Massachusetts in reference to sociodemographic variables such as racial/ethnicity and age groups, and provide evidence for patient-level interventions to those hardest hit by influenza. These findings provide valuable information about using large administrative databases to describe pandemic influenza cases and guide resource allocation to reduce disparities in relation to pandemic influenza preparedness.
89

Sulfhydryl Reducing Agents Distinguish Two Subtypes of Angiotensin II Receptors in the Rat Brain

Speth, Robert C., Rowe, Brian P., Grove, Kevin L., Carter, Michelle R., Saylor, David 10 May 1991 (has links)
Two angiotensin II receptor subtypes were distinguished in the rat brain using in vitro receptor autoradiography based on the differential effects of sulfhydryl reducing agents on 125I-sarcosine1, isoleucine8 angiotensin II binding in various brain nuclei. At several nuclei, e.g. the hypothalamus, circumventricular organs and the dorsal medulla, 125I-sarcosine1, isoleucine8 angiotensin II binding was strongly inhibited by 30 mM β-mercaptoethanol or 5 mM dithiothreitol, whereas at other nuclei, e.g. the lateral septum, colliculi, locus coeruleus and medial amygdala, sulfhydryl reducing agents had either little effect on radioligand binding or enhanced the binding. The distribution of the sulfhydryl reducing agent inactivated subtype corresponds exactly with the distribution of DuP 753 sensitive (designated as AIIα) 125I-sarcosine1, isoleucine8 angiotensin II binding sites25. The subtype not inhibited by sulfhydryl reducing agents corresponds with the DuP 753 insensitive (designated as AIIβ) sites in the brain25. The sulfhydryl reducing agent effect on brain angiotensin II receptor subtypes is similar to that seen in angiotensin II receptor subtypes in peripheral tissues. These observations indicate that many previous studies of brain angiotensin II receptor binding that included 5 mM dithiothreitol in the assay medium overlooked the sulfhydryl reducing agent inactivated (AIIα) receptor subtype.
90

Clinical Analytics and Personalized Medicine

Chih-Hao Fang (13978917) 19 October 2022 (has links)
<p>The increasing volume and availability of Electronic Health Records (EHRs) open up opportunities for computational models to improve patient care. Key factors in improving patient outcomes include identifying patient sub-groups with distinct patient characteristics and providing personalized treatment actions with expected improved outcomes. This thesis investigates how well-formulated matrix decomposition and causal inference techniques can be leveraged to tackle the problem of disease sub-typing and inferring treatment recommendations in healthcare. In particular, the research resulted in computational techniques based on archetypal analysis to identify and analyze disease sub-types and a causal reinforcement learning method for learning treatment recommendations. Our work on these techniques are divided into four part in this thesis:</p> <p><br></p> <p>In the first part of the thesis, we present a retrospective study of Sepsis patients in intensive care environments using patient data. Sepsis accounts for more than 50% of hospital deaths, and the associated cost ranks the highest among hospital admissions in the US. Sepsis may be misdiagnosed because the patient is not thoroughly assessed or the symptoms are misinterpreted, which can lead to serious health complications or even death. An improved understanding of disease states, progression, severity, and clinical markers can significantly improve patient outcomes and reduce costs. We have developed a computational framework based on archetypal analysis that identifies disease states in sepsis using clinical variables and samples in the MIMIC-III database. Each identified state is associated with different manifestations of organ dysfunction. Patients in different states are observed to be statistically significantly composed of distinct populations with disparate demographic and comorbidity profiles. We furthermore model disease progression using a Markov chain. Our progression model accurately characterizes the severity level of each pathological trajectory and identifies significant changes in clinical variables and treatment actions during sepsis state transitions. Collectively, our framework provides a holistic view of sepsis, and our findings provide the basis for the future development of clinical trials and therapeutic strategies for sepsis. These results have significant implications for a large number of hospitalizations.</p> <p><br></p> <p><br></p> <p>In the second part, we focus on the problem of recommending optimal personalized treatment policies from observational data. Treatment policies are typically based on randomized controlled trials (RCTs); these policies are often sub-optimal, inconsistent, and have potential biases. Using observational data, we formulate suitable objective functions that encode causal reasoning in a reinforcement learning (RL) framework and present efficient algorithms for learning optimal treatment policies using interventional and counterfactual reasoning. We demonstrate the efficacy of our method on two observational datasets: (i) observational data to study the effectiveness of right heart catheterization (RHC) in the initial care of 5735 critically ill patients, and (ii) data from the Infant Health and Development Program (IHDP), aimed at estimating the effect of the intervention on the neonatal health for 985 low-birth-weight, premature infants. For the RHC dataset, our method's policy prescribes right heart catheterization (RHC) for 11.5% of the patients compared to the best current method that prescribes RHC for 38% of the patients. Even with this significantly reduced intervention, our policy yields a 1.5% improvement in the 180-day survival rate and a 2.2% improvement in the 30-day survival rate. For the IHDP dataset, we observe a 3.16% improvement in the rate of improvement of neonatal health using our method's policy.</p> <p><br></p> <p>In the third part, we consider the Supervised Archetypal Analysis (SAA) problem, which incorporates label information to compute archetypes. We formulate a new constrained optimization problem incorporating Laplacian regularization to guide archetypes towards groupings of similar data points, resulting in label-coherent archetypes and label-consistent soft assignments. We first use the MNIST dataset to show that SAA can can yield better cluster quality over baselines on any chosen number of archetypes. We then use the CelebFaces Attributes dataset to demonstrate the superiority of SAA in terms of cluster quality and interpretability over competing supervised and unsupervised methods. We also demonstrate the interpretability of SAA decompositions in the context of a movie rating application. We show that the archetypes from SAA can be directly interpreted as user ratings and encode class-specific movie preferences. Finally, we demonstrate how the SAA archetypes can be used for personalized movie recommendations. </p> <p><br></p> <p>In the last part of this thesis, we apply our SAA technique to clinical settings. We study the problem of developing methods for ventilation recommendations for Sepsis patients. Mechanical ventilation is an essential and commonly prescribed intervention for Sepsis patients. However, studies have shown that mechanical ventilation is associated with higher mortality rates on average, it is generally believed that this is a consequence of broad use of ventilation, and that a more targeted use can significantly improve average treatment effect and, consequently, survival rates. We develop a computational framework using Supervised Archetypal Analysis to stratify our cohort to identify groups that benefit from ventilators. We use SAA to group patients based on pre-treatment variables as well as treatment outcomes by constructing a Laplacian regularizer from treatment response (label) information and incorporating it into the objective function of AA. Using our Sepsis cohort, we demonstrate that our method can effectively stratify our cohort into sub-cohorts that have positive and negative ATEs, corresponding to groups of patients that should and should not receive mechanical ventilation, respectively. </p> <p>We then train a classifier to identify patient sub-cohorts with positive and negative treatment effects. We show that our treatment recommender, on average, has a high positive ATE for patients that are recommended ventilator support and a slightly negative ATE for those not recommended ventilator support. We use SHAP (Shapley Additive exPlanations) techniques for generating clinical explanations for our classifier and demonstrate their use in the generation of patient-specific classification and explanation. Our framework provides a powerful new tool to assist in the clinical assessment of Sepsis patients for ventilator use.</p>

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