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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.
1

C5a receptor expression in severe sepsis and septic shock /

Furebring, Mia, January 2005 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2005. / Härtill 4 uppsatser.
2

Antibiotic-induced bacterial toxin release - inhibition by protein synthesis inhibitors /

Hjerdt-Goscinski, Gunilla, January 2004 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2004. / Härtill 5 uppsatser.
3

The role of toxic shock syndrome toxin-1 in the pathogenesis of toxic shock syndrome

Rosten, Patricia Melanie January 1986 (has links)
Toxic shock syndrome toxin-1 (TSST-1), an exoprotein produced by some strains of Staphylococcus aureus, is implicated in the pathogenesis of menstrual TSS. However, its role in nonmenstrual TSS is less certain. In order to study the pathogenetic role of TSST-1 in TSS, three approaches were taken: a) to develop an ELISA for detection of TSST-1 in biologic fluids in order to verify TSST-1 production in vivo in TSS patients, b) to quantitate TSST-1 specific antibodies in the serum of TSS patients and controls to determine whether such antibodies are protective, and c) to attempt to identify other staphylococcal products which may be implicated in some forms of TSS. A sensitive and specific noncompetitive enzyme-linked immunosorbent assay (ELISA) capable of detecting TSST-1 at concentrations from 0.5 to 16 ng/ml was developed. This assay did not detect other staphylococcal enterotoxins including A, B, C₁, C₂, C₃, D and E. Possible interference by protein A was readily eliminated by pretreatment of test samples with 10% nonimmune rabbit serum. The assay was adapted for rapid screening of TSST-1 production by S. aureus isolates in culture supernatants in vitro, and for the detection of TSST-1 in vaginal washings and urine of TSS patients and healthy controls in vivo. All 35 S. aureus isolates confirmed to be TSST-1 positive by Ouchterlony immunodiffusion, and 59 of 60 isolates confirmed to be TSST-1 negative, gave concordant results by ELISA. Interestingly, toxigenic S. aureus strains isolated from TSS patients quantitatively produced significantly more toxin in vitro compared to toxigenic control strains (p<0.05, Mann-Whitney rank sum test). TSST-1 could be detected by ELISA in 3 of 4 vaginal washings collected within 3 days of hospitalization from 3 women with acute menstrual TSS, compared to 0 of 17 washings from 9 TSS women collected greater than 3 days after hospitalization (p=0.003, Fisher's exact test) and 1 of 15 washings from 14 healthy control women (p=0.016). TSST-1 was not detected in the urine of 4 acute TSS patients, 2 convalescent TSS patients or in 3 control urine tested. A sensitive and reproducible ELISA was also developed for the quantitation of TSST-1 specific IgG in serum. Anti-TSST-1 was assessed in acute and convalescent sera from 16 nonmenstrual (9 female, 7 male) and 14 menstrual TSS patients, and from 87 healthy women and 66 healthy men as controls. Quantitative levels of anti-TSST-1 in the study groups were calculated as the percent of standard activity (POSA) relative to a medium titre reference serum standard. ELISA titers in acute sera from menstrual TSS (26.2 ± 5.2, mean POSA ± S.E.M.), but not nonmenstrual TSS women (71.8 ± 18.6), were significantly lower than in healthy controls (78.9 ± 7.3) (p<0.01, Mam-Whitney test). Titers from menstrual TSS patients remained low (25.2 ± 10.7) even during late convalescence (mean duration 20 months after illness onset), compared to healthy female controls (p<0.05). Acute titers in males with TSS (37.0 ± 15.6) were also significantly lower than those in control men (114.6 + 11.0) (p<0.05). An inverse relationship of recovery of toxigenic S. aureus and anti-TSST-1 titers in acute sera of TSS patients was observed. Interestingly, antibody titers in control men were significantly higher than in control women (p<0.001). No age-dependent effects or interactive effects of age and sex on ELISA titers were observed. To enable immunoblot analyses, TSST-1 was produced and partially purified using column chromatography techniques. Percent recovery of TSST-1 from culture supernatant through to the final procedure was approximately 15.5%. The relative purity of TSST-1 (TSST-l/total protein, w/w) was increased from 0.21% in culture supernatants to 94.4% in the final product. Ouchterlony immunoprecipitation against reference rabbit antitoxin demonstrated identity with reference TSST-1 as well as with TSST-1 prepared in other laboratories. Physical characterization demonstrated a molecular weight of 24 kd and a pi of 7.0. Using pooled normal human serum as a first antibody probe, several bands in addition to the 24 kd TSST-1 band were visualized by immunoblot against our partially purified toxin as well as similar preparations obtained from other investigators. To determine whether any of the additional bands might be implicated in TSS, acute and convalescent sera from TSS patients were used to probe for immunoreactive bands in our partially purified TSST-1 as well as a commercially obtained preparation. Seroconversion was demonstrated to the 24 kd TSST-1 protein in 7 of 10 TSS patients from whom toxigenic S. aureus was isolated. In addition, seroconversion was noted to a 49 kd band in 4 patients, to a 21 kd band in 3 patients, to a 28 kd band in 1 patient and to a 32 kd band in 2 patients. In conclusion: 1) the ability to measure TSST-1 in biologic fluids lends stronger support for the role of TSST-1 in menstrual TSS patients; 2) the serologic data support the etiologic role of TSST-1 in menstrual TSS and in nonmenstrual TSS patients from whom toxigenic S. aureus could be cultured, but not for nonmenstrual TSS women from whom toxigenic S. aureus was not isolated; 3) immunoblotting results with acute and convalescent sera from TSS and control patients, not only add further support to the role of TSST-1 in patients from whom toxigenic S. aureus could be isolated, but also indicate that there may be several other staphylococcal products implicated in TSS, particularly in whom antibody to TSST-1 pre-existed in acute sera. The nonresponsiveness or lack of seroconversion to TSST-1 in some patients could suggest either: a) TSST-1 was not the etiologic agent for such patients; b) TSST-1 was the etiologic agent, but the exposure was sufficient for an immune response (similar to tetanus), or; c) some immunologic defect may be present. Future studies are required to clarify these possibilities. / Science, Faculty of / Microbiology and Immunology, Department of / Graduate
4

Pathogenesis and immunotherapy of streptococcal septicemia and shock /

Ihendyane, Nahla, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 4 uppsatser.
5

Endothelin receptor antagonism and hypertonic solutions in experimental endotoxin shock /

Somell, Anna, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
6

Streptococcus pyogenes infections and toxic shock syndrome : molecular epidemiology and immunotherapy /

Darenberg, Jessica, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.
7

Cardiac function in experimental septic and non-septic conditions with special reference to the endothelin system /

Konrad, David, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 4 uppsatser.
8

Avaliação clínica de proteínas modeladoras da permeabilidade endotelial como biomarcadores para estratificação de risco na sepse em pacientes com neoplasias hematológicas e neutropenia febril / Clinical evaluation of modulators of endothelial permeability as biomarkers for risk stratification in sepsis patients with hematological malignancies and febrile neutropenia

Fiusa, Maiara Marx Luz, 1987- 22 August 2018 (has links)
Orientador: Erich Vinicius de Paula / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-22T16:41:35Z (GMT). No. of bitstreams: 1 Fiusa_MaiaraMarxLuz_M.pdf: 4773403 bytes, checksum: 75096ce572a7e0682b295f48ac895796 (MD5) Previous issue date: 2013 / Resumo: A neutropenia febril (NF) em pacientes com neoplasias hematológicas é caracterizada pelo alto risco de sepse e choque séptico. Embora a utilização de escores clínicos como o MASCC permita a identificação de pacientes de baixo risco, este escore é menos informativo em pacientes de alto risco, onde se encaixam a maioria dos pacientes com neoplasias hematológicas, além daqueles submetidos a esquemas intensivos de quimioterapia. Ao mesmo tempo, a aplicação de biomarcadores de gravidade como a procalcitonina, validados em pacientes não-neutropênicos, é controversa em pacientes com NF. A quebra da barreira endotelial é um elemento chave no choque séptico, de modo que proteínas envolvidas neste processo são candidatos atrativos como biomarcadores de gravidade na sepse. Neste estudo, avaliamos prospectivamente o valor da dosagem de VEGF-A, sFlt-1, Ang-1 e Ang-2 como biomarcadores da evolução para choque séptico em 120 pacientes com NF. Pacientes internados nas enfermarias de Hematologia e Transplante de Medula Óssea do HC da UNICAMP para tratamento de NF entre março de 2011 e 2012 foram convidados a participar. As amostras foram coletadas na manhã seguinte à entrada no estudo, junto com a coleta de exames de rotina. O estudo foi desenhado com o objetivo de mimetizar as condições de coleta e processamento das amostras, que seriam encontradas na prática clínica real. Foi avaliada a evolução para choque séptico e mortalidade em 28 dias. Os resultados foram comparados com marcadores de prognóstico clássicos como proteína C reativa, e escores MASCC e SOFA. No total, 99 pacientes preencheram os critérios de inclusão, dos quais 19,8% evoluíram com choque séptico. Não foram observadas diferenças clínicas e demográficas entre os pacientes com NF não-complicada e choque séptico, exceto pelo escore SOFA, significativamente mais elevado no segundo grupo. Os níveis de VEGF-A e sFlt-1 foram semelhantes entre os dois grupos. Em contraste, os níveis séricos de Ang-2 estavam aumentados em pacientes com choque séptico, ao passo que os níveis séricos de Ang-1 estavam diminuídos. Considerando o papel antagônico destas angiopoietinas na regulação da permeabilidade endotelial, a relação Ang-2/Ang-1 foi calculada, como indicador de desequilíbrios na concentração destes moduladores, que pudessem indicar um estado mais ou menos propenso à queda da barreira endotelial. De fato, um aumento na relação Ang-2/Ang-1 foi encontrada em pacientes com choque séptico (5,29 - variação de 0,58 a 57,14) em relação aos pacientes com NF não-complicada (1,99 - variação de 0,06 a 64,62; P=0,01). Na análise univariada e multivariada, a relação Ang-2/Ang-1 provou ser um fator de risco independente para o desenvolvimento de choque séptico e mortalidade em 28 dias. Desta forma, concluímos que a elevação dos níveis séricos de Ang-2 e da relação Ang-2/Ang-1 está associada ao risco aumentado de choque séptico e mortalidade em pacientes com NF, mesmo quando coletada sob condições próximas àquelas encontradas a prática clínica / Abstract: Febrile neutropenia (FN) in patients with hematologic malignancies is characterized by a high risk of sepsis complications and septic shock. Although the use of clinical scores such as the MASCC allows the identification of low-risk patients, this score is much less informative in high-risk patients, a category in which most patients with hematologic malignancies, and those undergoing intensive chemotherapy regimens, fit in. At the same time, the use of classical biomarkers such as procalcitonin in non-neutropenic patients is controversial in patients with FN. Endothelial barrier breakdown is a key element in septic shock, so that proteins involved in this process are attractive candidates as biomarkers of sepsis severity. In this study, we prospectively evaluated the value of VEGF-A, sFlt-1, Ang-1 and Ang-2 serum levels as biomarkers of progression to septic shock in 120 patients with FN. Patients hospitalized in the Hematology and Bone Marrow Transplantation in-patient units of a university hospital (HC-UNICAMP) for the treatment of FN between March 2011 and March 2012 were invited to participate. Samples were collected in the following morning after study entry, along with the collection of routine labs. The study was designed to mimic the conditions of blood sample collection and processing that would be encountered in "real-world" clinical practice. Clinical outcomes were (1) progression to septic shock and (2) death within 28 days from fever onset. Results were compared with classical prognostic markers such as C-reactive protein, and MASCC and SOFA scores. In total, 99 patients met the inclusion criteria, of which 19.8% progressed to septic shock. No differences clinical and demographic differences were observed between patients with uncomplicated-FN or septic shock, except for a higher SOFA scores in the latter group. Levels of VEGF-A and sFlt-1 were similar between the two groups. In contrast, serum levels of Ang-2 were increased in patients with septic shock, whereas serum levels of Ang-1 were decreased in these patients. Considering the antagonistic role of angiopoietins 1 and 2 in regulating endothelial permeability, the Ang-2/Ang-1 ratio was calculated as an indicator of imbalances in the concentration of these modulators. In fact, a high Ang-2/Ang-1 ratio was found in patients with septic shock (5.29 - range 0.58 to 57.14) compared to patients with uncomplicated FN (1.99 - range 0.06 to 64.62, P = 0.01). In univariate and multivariate analysis, the Ang-2/Ang-1 ratio proved to be an independent risk factor for the development of septic shock and for 28-day sepsis-related mortality. Thus, we concluded that a high Ang-2/Ang-1 ratio is associated with increased risk of septic shock and mortality in patients with FN, even when collected under conditions close to those encountered in real-world clinical practice / Mestrado / Clinica Medica / Mestra em Ciências
9

Impacto da terapia farmacológica de suporte nas variáveis hemodinâmica, de função renal e mortalidade de pacientes em sepse grave e choque séptico / The impact of pharmacological support therapy in hemodynamic, renal function and patient mortality variables in severe sepsis and septic shock

Miranda, Milena Penteado Ferraro 15 December 2009 (has links)
A sepse grave e o choque séptico são complicações decorrentes de um processo infeccioso, associados à alta mortalidade em UTI e caracterizados por disfunção cardiovascular, renal e metabólica. A terapia farmacológica (TF) visa oferecer suporte hemodinâmico e reduzir níveis glicêmicos. Nesse cenário, o presente estudo objetivou analisar o impacto da TF e da alteração glicêmica na evolução clinica do paciente em sepse grave e choque séptico nas primeiras 72 horas.Trata-se de um ensaio clínico controlado randomizado em que os pacientes (n=46) foram alocados em grupos glicêmicos intensivo (manutenção da glicemia entre 80-110mg/dl) e convencional (manutenção da glicemia entre180-220mg/dl). Os dados foram coletados no período de 2004-2006 em um Hospital Universitário do Município de São Paulo. Na análise estatística foram usados os testes t-student, Qui-Quadrado, sendo considerados significativo p<0,05. Os resultados mostraram que a amostra foi constituída por pacientes do sexo masculino (58,7%), clínicos (78,3%) que apresentaram choque séptico (78,3%) decorrente de infecções no sistema respiratório (39,1%), com disfunção cardíaca (36,9%) e que apresentaram lesão renal aguda (56,5%). A média de idade foi de 51,6 anos. Os medicamentos de suporte mais prescritos foram noradrenalina (69,6%; 56,5%), hidrocortisona (56,5%;67,4%) e insulina (67,4%;73,9%), nas 24 e 48 h. Na comparação entre os grupos, observou-se diferença estatisticamente significante (p=0,00) na média glicêmica; não houve diferença estatisticamente significantes para as variáveis FC mínima (p= 0,68), máxima (p=0,11), PAM mínima (p=0,06) e máxima (p=0,11), no DU (p=0,23), Cr (p=0,33), volume infundido de cristalóides (p=0,10) e na mortalidade (p=0,11). A instabilidade hemodinâmica no grupo convencional foi mais duradoura e os óbitos ocorreram, apenas, entre os pacientes alocados no grupo convencional. Dessa forma, os dados sugerem que o controle glicêmico intensivo favorece o restabelecimento hemodinâmico de pacientes em choque séptico e, de certo modo, os protege do desfecho mortalidade / Severe sepsis and septic shock are complications that develop from an inflammatory process leading to high mortality in the intensive care unit (ICU) and characterized by cardiovascular, renal and metabolic dysfunction. The pharmacological therapy (PT) aims at offering hemodynamic support and at reducing glycemic levels. In this scenario, the present study had the objective of analyzing the impact of PT and of the glycemic alteration in the clinical evolution of severe sepsis and septic shock patients in the first 72 hours. This is a randomized control trial in which the patients (n=46) were divided into intensive glycemic group (maintenance of glycemia between 80-110mg/dl) and conventional glycemic group (maintenance of glycemia between 180-220 mg/dl). The data were collected in the 2004-2006 period in a University Hospital in the city of São Paulo. In the statistical analysis, the tests used were t-student, Qui-Quadrado, being considered meaningful p<0,05. The results showed that the sample was formed by male patients (58.7%), clinical patients (78.3%) that presented septic shock (78.3%) as a result of infection in the respiratory system (39.1%), with cardiac dysfunction (36.9%) and those that presented acute renal lesion (56.5%). The average age was 51.6 years. The most commonly prescribed support drugs were noradrenaline (69.6%, 56.5%) and hydrocortisone (56.5%, 67.4%) in the first 24 and 48 hours. In the comparison between groups, statistically significant difference was observed (p=0,00) in the glycemic average, there was no statistically significant difference for the variables: minimal FC (p=0,68), maximum (p=0,11), minimum PAM (p=0,06) and maximum (p=0,11), DU (p=0,23), CR (p=0,33), volume infundido de cristalóides (p=0,10) and mortality (p=0,11). The hemodynamic instability in the conventional group lasted longer and deaths occurred only among the conventional group patients. Therefore, the data suggest that the intensive glycemic control favors the hemodynamic recovery of septic shock patients and, in a way, protects them from death
10

Efeitos do sildenafil em modelo experimental de endotoxemia em suínos / Effects of sildenafil in experimental model of endotoxemia in pigs

Kemper, Daniella Aparecida Godoi 16 December 2015 (has links)
INTRODUÇÃO: Apesar de todos os esforços, as taxas de mortalidade no choque séptico ainda são altas, e entre as diversas complicações deste quadro, a hipertensão pulmonar é considerada um fator agravante. O sildenafil é um fármaco com efeito vasodilatador arterial pulmonar que atua através da inibição da fosfodiesterase 5, aumentando o GMPcíclico e promovendo relaxamento da musculatura lisa. OBJETIVO: Avaliar se a administração de sildenafil atenua as alterações hemodinâmicas ocasionadas pelo choque endotoxêmico, bem como os parâmetros de ventilação e oxigenação em modelo experimental de endotoxemia em suínos. MÉTODOS: Foram utilizados 20 suínos nos quais o choque endotoxêmico foi induzido através da infusão intravenosa de LPS (4ug/kg/h). Os animais foram randomizados e alocados da seguinte maneira: Controle (CTL, n=10) - submetidos apenas ao choque endotoxêmico; Sildenafil (SIL, n=10) - tratados com sildenafil na dose de 100 mg por via oral antes de serem submetidos ao choque endotoxêmico. Foram avaliados os parâmetros hemodinâmicos, ventilatórios, e de oxigenação, a partir do momento Basal até 180 minutos da infusão de LPS. Os efeitos inflamatórios e de lesão miocárdica também foram avaliados, bem como a análise histopatológica do tecido pulmonar. Os dados paramétricos foram analisados utilizando ANOVA de duas vias para medidas repetidas, seguidas por Tukey quando necessário, enquanto para os dados não paramétricos utilizou-se o teste de Mann-Whitney. RESULTADOS: A endotoxemia induziu hipertensão pulmonar com aumento significativo na pressão arterial pulmonar e no índice de resistência vascular pulmonar, e também diminuição na PaO2 / FiO2. A pressão arterial pulmonar e sistêmica foram significativamente menores no grupo Sildenafil, sendo que o os valores máximos de PAPM observados aos 30 minutos de infusão de LPS foram 35 e 52 mmHg, nos grupos Sildenafil e Controle, respectivamente. O Sildenafil manteve a oxigenação, através de maior relação PaO2/FiO2 e maior SvO2, porém não apresentou efeito sobre a fração de shunt intrapulmonar. Todas as citocinas e a troponina aumentaram após a infusão de LPS e não foi observada diferença significativa entre os grupos. O sildenafil não atenuou as lesões histopatológicas decorrente do choque endotoxêmico. CONCLUSÃO: O sildenafil atenuou a hipertensão pulmonar induzida pela endotoxemia, porém acarretou diminuição da pressão arterial sistêmica. O sildenafil manteve a oxigenação sem alterar a fração de shunt intrapulmonar. Não houve efeitos sobre as lesões pulmonares, nas citocinas inflamatórias e na troponina I cardíaca / INTRODUCTION: Despite all efforts, mortality rates in septic shock are still high, and among the various complications pulmonary hypertension is considered a poor prognostic factor. Sildenafil is a drug with pulmonary arterial vasodilator effect, acts through inhibition of phosphodiesterase V that increases GMPc promoting the vasodilator effect. OBJECTIVE: Evaluate if sildenafil attenuates hemodynamic changes caused by septic shock, as well as ventilation and oxygenation parameters in an experimental model of endotoxemia in pigs. METHODS: Twenty pigs in which endotoxemia was induced through intravenous LPS infusion (4ug/kg/h) were randomly assigned to Control group (CTL, n = 10) - which received saline solution previous the endotoxemia; or to Sildenafil group (SIL, n = 10) - which received sildenafil orally (100 mg) previous the endotoxemia. Hemodynamic, ventilation and oxygenation were evaluated from at baseline up to 180 minutes of LPS infusion. The inflammatory and myocardial damage effects were also evaluated. Lung tissue was collected for histological analysis. Parametric data were compared using two-way repeated measures ANOVA, followed by Tukey test when necessary, while for non-parametric data the Mann-Whitney test was used. RESULTS: Endotoxemia induced pulmonary hypertension with an increase in pulmonary arterial pressure and pulmonary vascular resistance index and also a decrease in PaO2/FiO2. Pulmonary and systemic arterial pressures were significantly lower in the Sildenafil group, wherein the PAPM maximum values observed at 30 minutes of LPS infusion were 35 and 52 mmHg in the sildenafil and control groups, respectively. Sildenafil maintained oxygenation with superior PaO2/FiO2 and higher SvO2, but had no effect on intrapulmonary shunt. All cytokines and troponin increased after LPS infusion and there was no significant intergroup difference. Sildenafil did not attenuate the histologic alterations from endotoxemic shock. CONCLUSION: Sildenafil attenuated pulmonary hypertension induced by endotoxemia, but decreased systemic blood pressure. Sildenafil maintained oxygenation without effecting shunt fractioning. There was no effect in lung injuries, cytokines and troponin

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