Diss. (sammanfattning) Linköping : Linköpings universitet, 2008. / Härtill 6 uppsatser.

Rhodococcus fascians is a Gram-positive phytopathogenic bacterium which induces the development of leafy galls, local amplifications of multiple buds, on most infected plants. This process is linked to the production of phytohormones along with the presence of essential virulence-associated genes like the plasmid loci att and fas and the chromosomal gene vicA. However, the presence of these genes is not sufficient to ensure the infection phenotype development, indicating that other genes play a role in R. fascians pathogenicity. In this work, we studied the metabolic modifications occurring when the bacterium interacts with its host using a proteomic approach. A comparison between virulent and avirulent strains showed variations in the expression of catalases. In the virulent strain, besides the transitory induction of the att locus expression, the bacterium changes its metabolism from the Krebs cycle to the glyoxylate shunt, a process which is frequently observed in bacteria confronted to a hostile environment. The expression of the shunt-specific enzyme isocitrate lyase increased, while expression of fumarate hydratase and pyruvate dehydrogenase decreased. Hence, we focused on the link between the glyoxylate shunt and virulence. A screening of a R. fascians mutant library based on the capacity of bacteria to use acetate as the sole carbon source, a metabolic pathway depending on the glyoxylate shunt, resulted in the identification of a new gene essential for R. fascians pathogenicity. This gene encodes a glycosyl transferase, an enzyme known to be involved in the bacterial cell wall biosynthesis but possibly also implicated in cytokinin secretion. A mutant in this gene harboured an altered colony phenotype and could not induce malformations on infected plants. Accordingly, our results were integrated in the leafy gall pathology model recently presented by Stes et al. (2011). Finally, the several questions that are raised by this work, allowed us to suggest further research perspectives in order to unveil a little more of the R. fascians mysterious ways to interact with the plant./Rhodococcus fascians est une bactérie Gram-positive phytopathogène qui induit le développement de galles feuillées, des amplifications locales de multiples bourgeons, sur la plupart des plantes infectées. Ce processus est lié à la production de phytohormones ainsi qu’à la présence de gènes essentiels associés à la virulence tels que les loci plasmidiques att et fas et le gène chromosomique vicA. Cependant, la présence de ces gènes ne suffit pas à garantir le développement du phénotype d’infection, indiquant que d’autres gènes jouent un rôle dans la pathogénicité de R. fascians. Dans ce travail, nous avons étudié les modifications métaboliques qui se produisent lorsque la bactérie interagit avec son hôte par une approche protéomique. Une comparaison entre les souches virulente et avirulente a mis en évidence des variations d’expression au niveau des catalases. Dans la souche virulente, outre l’induction transitoire de l’expression du locus att, la bactérie change son métabolisme pour passer du cycle de Krebs au shunt du glyoxylate, un processus fréquemment observé chez les bactéries confrontées à un environnement hostile. L’expression de l’isocitrate lyase, enzyme spécifique au shunt, augmente, tandis que celle de la fumarate hydratase et de la pyruvate déhydrogénase diminue. Nous nous sommes donc intéressés au lien entre le shunt du glyoxylate et la virulence. Le screening d’une banque de mutants de R. fascians basé sur la capacité de la bactérie à utiliser l’acétate comme seule source de carbone, une voie métabolique dépendant du shunt du glyoxylate, a permis d’identifier un nouveau gène essentiel pour la pathogénicité de R. fascians. Ce gène code pour une glycosyl transferase, une enzyme impliquée dans la biosynthèse de la paroi bactérienne mais également dans la sécrétion des cytokinines. Un mutant dans ce gène présente un phénotype de colonie altéré et ne peut induire de malformations chez les plantes infectées. Finalement, nos résultats et les pistes d’interprétations que nous avons émisent nous permettent de compléter le modèle de l’interaction R. fascians-plante proposé récemment par Stes et al. (2011). Des perspectives de recherches visant une meilleure compréhension de ce pathosystème sont proposées. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

As infecções por bactérias representam um grave problema hoje e para o futuro, devido ao fato de que estes microrganismos desenvolvem mecanismos de resistência aos antibióticos ao longo do tempo de uso. A formação de biofilmes também é um fator a ser discutido no cenário atual por estar associado a muitas infecções bacterianas humanas, principalmente àquelas envolvendo dispositivos médicos aumentando assim os riscos de infecções hospitalares. O ácido ursólico (AU) é um triterpeno conhecido por suas atividades biológicas relatadas. Apresenta moderada atividade antibacteriana, porém tem demonstrado importante citotoxicidade frente a algumas linhagens celulares. Em vista disso, neste trabalho se desenvolveu uma série de novas moléculas derivadas do AU com alterações nas posições C-3 e C-28. Quatro moléculas com substituição em C-3 (derivados 2, 3, 4e 5) e uma com substituição em C-3 e C-28 (derivado 6) foram comparadas ao AU (1) quanto a atividade antibacteriana. As cepas utilizadas foram Salmonela Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Staphylococcus epidermidis e Staphylococcus aureus. Os compostos 3 e 6 apresentaram melhor perfil inibitório de forma geral, onde 3 apresentouse bactericida para S. aureus e S. epidermidis (Gram positivas) e paraP. mirabilis (Gram negativa) apresentou-se bacteriostático. / The ursolic acid (UA) is a triterpene known for their biological activities reported. Thus, become useful techniques semi-synthesis starting from natural products extracted, for example residue industries in order to improve the pharmacological properties decreasing toxicity. The bacterial infections are a serious problem today and in the future due to the fact that these organisms develop resistance mechanisms to antibiotics over time of use. The formation of biofilms is also a factor to be discussed in the current scenario because of being responsible for a very high number of rejections and other prosthetic devices by increasing the risk of nosocomial infections. The AU has a moderate antibacterial activity reported in the literature, but showed significant cytotoxicity against some cell lines. In view of this it developed a series of new molecules derived from AU residues extracted from apples (Mallus domestica) from the juice industry by promoting the so-called green chemistry. The molecules undergo changes in C-3 and C-28. Four molecules with substitution at C-3 (derived from 2, 3, 4 and 5) and one with substitution at C-3 and C-28 (derived 6) were compared with au (1). The strains used in the tests of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration were Salmonella Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Staphylococcus epidermidis and Staphylococcus aureus. Compounds 3 and 6 had better inhibitory profile in general, where three presented bactericidal to S. aureus and S. epidermidis (Gram positive) and P. mirabilis (Gram negative) appeared bacteriostatic.

No description available.

As infecções por bactérias representam um grave problema hoje e para o futuro, devido ao fato de que estes microrganismos desenvolvem mecanismos de resistência aos antibióticos ao longo do tempo de uso. A formação de biofilmes também é um fator a ser discutido no cenário atual por estar associado a muitas infecções bacterianas humanas, principalmente àquelas envolvendo dispositivos médicos aumentando assim os riscos de infecções hospitalares. O ácido ursólico (AU) é um triterpeno conhecido por suas atividades biológicas relatadas. Apresenta moderada atividade antibacteriana, porém tem demonstrado importante citotoxicidade frente a algumas linhagens celulares. Em vista disso, neste trabalho se desenvolveu uma série de novas moléculas derivadas do AU com alterações nas posições C-3 e C-28. Quatro moléculas com substituição em C-3 (derivados 2, 3, 4e 5) e uma com substituição em C-3 e C-28 (derivado 6) foram comparadas ao AU (1) quanto a atividade antibacteriana. As cepas utilizadas foram Salmonela Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Staphylococcus epidermidis e Staphylococcus aureus. Os compostos 3 e 6 apresentaram melhor perfil inibitório de forma geral, onde 3 apresentouse bactericida para S. aureus e S. epidermidis (Gram positivas) e paraP. mirabilis (Gram negativa) apresentou-se bacteriostático. / The ursolic acid (UA) is a triterpene known for their biological activities reported. Thus, become useful techniques semi-synthesis starting from natural products extracted, for example residue industries in order to improve the pharmacological properties decreasing toxicity. The bacterial infections are a serious problem today and in the future due to the fact that these organisms develop resistance mechanisms to antibiotics over time of use. The formation of biofilms is also a factor to be discussed in the current scenario because of being responsible for a very high number of rejections and other prosthetic devices by increasing the risk of nosocomial infections. The AU has a moderate antibacterial activity reported in the literature, but showed significant cytotoxicity against some cell lines. In view of this it developed a series of new molecules derived from AU residues extracted from apples (Mallus domestica) from the juice industry by promoting the so-called green chemistry. The molecules undergo changes in C-3 and C-28. Four molecules with substitution at C-3 (derived from 2, 3, 4 and 5) and one with substitution at C-3 and C-28 (derived 6) were compared with au (1). The strains used in the tests of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration were Salmonella Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Staphylococcus epidermidis and Staphylococcus aureus. Compounds 3 and 6 had better inhibitory profile in general, where three presented bactericidal to S. aureus and S. epidermidis (Gram positive) and P. mirabilis (Gram negative) appeared bacteriostatic.

This study proposes to directly test the hypothesis that antibody-dependent enhancement (ADE) is the critical factor in the development of dengue hemorrhagic fever (DHF) in infants. DHF occurs in two distinct clinical settings: a) in children and adults with secondary DENV infection, and b) in infants with primary DENV infection born to mothers with prior DENV infection. The ADE hypothesis proposes that pre-existing serotype-cross-reactive non-neutralizing anti-DENV antibodies bind the heterotypic DENV during secondary infection and enhance its uptake into immune cells, leading to increased viral load and DHF. This model suggests that DHF in DENV-infected infants is caused by the enhancing effect of waning maternal anti-DENV antibodies, thus causing a “physiologic secondary infection” during an infant’s primary infection and thereby increasing the infant’s risk for DHF. The effect of maternal immunity on DHF in infants has been studied exclusively in Southeast Asia. However, the maternal DENV seroprevalence approaches 100% in this part of the world. As a consequence, the ADE model of infant DHF cannot truly be tested in Southeast Asia, because all infants possess anti-DENV antibody at birth. In the Western Hemisphere, by contrast, women may have experienced either a single DENV infection, more than one DENV infection, or no DENV infection at all. The ability to include DENV-seronegative mothers as controls allows for the ADE hypothesis to be directly tested in a clinical study. To our knowledge, no such study has been previously conducted. This thesis presents a case-control study designed to evaluate the influence of positive maternal dengue seroprevalence on the risk of DHF in infants. As the MSCI program provides instruction in study design, this thesis does not present findings. The clinical trial described herein began in May 2010 and enrollment is expected to continue through May 2012 (see Table 4).

INTRODUÇÃO: Os hepatócitos apresentam papel potencial em iniciar e amplificar a resposta inflamatória aguda no fígado, através da liberação de citocinas pró-inflamatórias, em papel complementar ao exercido pelas células de Kupffer e endoteliais. A invasão bacteriana da célula hepática é um estímulo para que o hepatócito produza citocinas como o TNF-alfa, capaz de induzir sua própria morte por apoptose. O TNF-alfa pode ser tanto um agente citotóxico (induzindo a morte celular), quanto um agente protetor (através da ativação de NF-kB). A morte por apoptose do hepatócito libertaria as bactérias que seriam destruídas pelo sistema imunológico hepático ativado. Salmonella Typhimurium (ST) e Listeria monocytogenes (LM) são patógenos responsáveis por importantes doenças de origem alimentar. O hepatócito é o maior local de replicação bacteriana no fígado. As conseqüências da invasão bacteriana dos hepatócitos e sua repercussão na produção de TNF-alfa e na morte celular necessitam ser melhor xxix avaliadas. MÉTODOS: Nesse estudo procuramos investigar o comportamento dos hepatócitos invadidos por ST e LM sorogrupos 4a, 4b e 1/2a, analisando os seguintes parâmetros: a) morfologia = por microscopia óptica (MO) (hematoxilina e eosina) e por microscopia eletrônica (ME); b) dosagem do TNF-alfa liberado pelos hepatócitos invadidos = o TNF-alfa liberado foi detectado por técnica ELISA no sobrenadante das culturas; c) pesquisa da morte celular por apoptose = avaliada através das técnicas TUNEL e anexina (citometria de fluxo). Para todos os parâmetros foi realizada análise comparativa estatística entre os quatro tipos de bactéria. RESULTADOS: As monocamadas de hepatócitos agredidas por Listeria monocytogenes e Salmonella Typhimurium apresentam ruptura em sua distribuição, e sinais de desorganização citoplasmática e nuclear. Para as bactérias ST, LM 4a, LM 4b e LM 1/2a obtivemos os seguintes valores em seqüência: a) taxa de liberação de TNF-alfa (pg/mL): 146,9±18,38; 94,71±13,89; 94,52±15,66 e 58,16±15,49; b) capacidade de produção de TNF-alfa (pg/mL): -67,20±71,56; -46,49±54,10; -106,3±61,0 e 58,16±15,49; c) taxa de apoptose avaliada por TUNEL em unidade de área (UA): 23,86±1,614; 15,92±0,9343; 21,14±1,421 e 23,93±1,263; d) capacidades de produção de apoptose por TUNEL em UA: -50,67±12,42; 10,81±7,186; - 17,22±10,93 e -40,27±9,712; e) taxas de apoptose por anexina em UA: 12,51±2,052; 23,10±3,481; 26,61±3,414 e 18,57±2,497; f) capacidades de produção de apoptose por anexina em UA: -63,31±15,79; -126,4±26,78; - 142,0±26,26 e -97,75±19,21. CONCLUSÕES: a) ocorre liberação de TNFxxx alfa pelos hepatócitos invadidos, sendo que a Salmonella Typhimurium foi responsável pela maior taxa de liberação de TNF-alfa, e Listeria monocytogenes 4b pela maior capacidade de produção de TNF-alfa; b) ocorre morte por apoptose dos hepatócitos invadidos por bactérias, avaliada através da técnica TUNEL, sendo que Salmonella Typhimurium e Listeria monocytogenes 1/2a foram responsáveis pelas maiores taxas e capacidades de produção de apoptose; c) ocorre morte dos hepatócitos invadidos por apoptose, avaliada através da técnica da anexina, sendo que Listeria monocytogenes 4b foi responsável pelas maiores taxas e capacidades de produção de apoptose; d) os hepatócitos cultivados invadidos pelas bactérias Salmonella Typhimurium e Listeria monocytogenes apresentam alterações morfológicas, com ruptura da distribuição da monocamada, e sinais de desorganização citoplasmática e nuclear / INTRODUCTION: Hepatocytes can play an important role in the initiation or amplification of the hepatic acute inflammatory response, through the release of proinflammatory cytokines. The bacterial invasion of hepatocyte is a stimulus for production of TNF-alpha by these cells, and this phenomenon induces its own death by apoptosis. TNF-alpha is as a cytotoxic agent (inducing cellular death), as a protector agent (through NF-kB activation). The hepatocyte death by apoptosis may release intracellular bacteria that would be destroyed by hepatic immunological system. Salmonella Typhimurium (ST) and Listeria monocytogenes (LM) are important foodborne pathogens. The hepatocyte is the major site of bacterial replication in the liver. The consequences of hepatocytes bacterial invasion must be better evaluated. METHODS: In the present work we show the behavior of hepatocytes invaded by ST and LM serotypes 4a, 4b and 1/2a, through: a) morphology = by optic microscopy (OM) (hematoxylin-eosin staining) and electronic microscopy (EM); b) quantification of TNF-alpha released by hepatocytes = TNF-alpha released was determined by ELISA in culture supernatants; c) evaluation of apoptotic cell death by TUNEL and annexin techniques (flow cytometry). For all parameters were made a statistical comparative analysis among the four types of bacteria. RESULTS: The hepatocytes monolayers invaded by LM and ST presented ruptures in your organization, and signs of nuclear and cytoplasmic disorder. For the bacteria ST, LM 4a, LM 4b and LM 1/2a we obtained the following values respectively: a) rate of TNF-alpha released (pg/mL): 146,9±18,38; 94,71±13,89; 94,52±15,66 and 58,16±15,49; b) capacities of TNF-alpha production (pg/mL): -67,20±71,56; -46,49±54,10; -106,3±61,0 and 58,16±15,49; c) rate of apoptosis by TUNEL in unit of area (UA): 23,86±1,614; 15,92±0,9343; 21,14±1,421 and 23,93±1,263; d) capacities of apoptosis production by TUNEL in UA: -50,67±12,42; 10,81±7,186; - 17,22±10,93 and -40,27±9,712; e) rate of apoptosis by annexin in UA: 12,51±2,052; 23,10±3,481; 26,61±3,414 and 18,57±2,497; f) capacities of apoptosis production by annexin in UA: -63,31±15,79; -126,4±26,78; - 142,0±26,26 and -97,75±19,21. CONCLUSIONS: a) ST was responsible for the major rate of TNF-alpha released and LM 4b was responsible for the major capacity of TNF-alpha production; b) ST and LM 1/2a caused the major rates and capacities of apoptosis,production, evaluated by TUNEL technique; c) LM 4b was responsible for the major rates and capacities of apoptosis production, evaluated by annexin technique; d) the cultured hepatocytes invaded by bacteria ST and LM presented morphological alterations, with monolayer rupture, and signs of nuclear and cytoplasmic disorder

As infecções por bactérias representam um grave problema hoje e para o futuro, devido ao fato de que estes microrganismos desenvolvem mecanismos de resistência aos antibióticos ao longo do tempo de uso. A formação de biofilmes também é um fator a ser discutido no cenário atual por estar associado a muitas infecções bacterianas humanas, principalmente àquelas envolvendo dispositivos médicos aumentando assim os riscos de infecções hospitalares. O ácido ursólico (AU) é um triterpeno conhecido por suas atividades biológicas relatadas. Apresenta moderada atividade antibacteriana, porém tem demonstrado importante citotoxicidade frente a algumas linhagens celulares. Em vista disso, neste trabalho se desenvolveu uma série de novas moléculas derivadas do AU com alterações nas posições C-3 e C-28. Quatro moléculas com substituição em C-3 (derivados 2, 3, 4e 5) e uma com substituição em C-3 e C-28 (derivado 6) foram comparadas ao AU (1) quanto a atividade antibacteriana. As cepas utilizadas foram Salmonela Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Staphylococcus epidermidis e Staphylococcus aureus. Os compostos 3 e 6 apresentaram melhor perfil inibitório de forma geral, onde 3 apresentouse bactericida para S. aureus e S. epidermidis (Gram positivas) e paraP. mirabilis (Gram negativa) apresentou-se bacteriostático. / The ursolic acid (UA) is a triterpene known for their biological activities reported. Thus, become useful techniques semi-synthesis starting from natural products extracted, for example residue industries in order to improve the pharmacological properties decreasing toxicity. The bacterial infections are a serious problem today and in the future due to the fact that these organisms develop resistance mechanisms to antibiotics over time of use. The formation of biofilms is also a factor to be discussed in the current scenario because of being responsible for a very high number of rejections and other prosthetic devices by increasing the risk of nosocomial infections. The AU has a moderate antibacterial activity reported in the literature, but showed significant cytotoxicity against some cell lines. In view of this it developed a series of new molecules derived from AU residues extracted from apples (Mallus domestica) from the juice industry by promoting the so-called green chemistry. The molecules undergo changes in C-3 and C-28. Four molecules with substitution at C-3 (derived from 2, 3, 4 and 5) and one with substitution at C-3 and C-28 (derived 6) were compared with au (1). The strains used in the tests of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration were Salmonella Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Staphylococcus epidermidis and Staphylococcus aureus. Compounds 3 and 6 had better inhibitory profile in general, where three presented bactericidal to S. aureus and S. epidermidis (Gram positive) and P. mirabilis (Gram negative) appeared bacteriostatic.

INTRODUÇÃO: Lesão renal aguda (LRA) é uma complicação comum da cirrose frequentemente desencadeada por infecções bacterianas. A mortalidade de pacientes com cirrose e LRA varia de 10 a 100% a depender do estádio da cirrose, etiologia e progressão da LRA e tratamento recebido. Pacientes com LRA que progride possuem mortalidade intra-hospitalar consideravelmente maior do que aqueles que não progridem. Os critérios diagnósticos da LRA baseiam-se na creatinina sérica. Porém, esse biomarcador tem acurácia diagnóstica limitada, já que demora até 48 horas para se alterar e não distingue a etiologia da LRA. Essa última limitação é particularmente importante em pacientes com suspeita de síndrome hepatorrenal (SHR), já que o seu tratamento envolve o uso de medicações de alto custo (albumina e terlipressina) e eficácia limitada. O NGAL (neutrophil gelatinase-associated lipocalin) é um biomarcador de necrose dos túbulos renais e sua dosagem tem sido proposta como marcador diagnóstico mais acurado da LRA na cirrose, pois se altera mais precocemente e seus níveis urinários variam conforme a etiologia e gravidade da LRA. OBJETIVOS: Os objetivos primários do trabalho foram avaliar a acurácia do NGAL urinário para predizer: a) desenvolvimento ou progressão da LRA em pacientes com cirrose e infecção bacteriana; b) resposta ao tratamento combinado com albumina e terlipressina em pacientes com diagnóstico estabelecido de SHR. Os objetivos secundários foram: a) acurácia de marcadores de disfunção hemodinâmica em cirrose (atividade plasmática de renina e noradrenalina sérica) na predição do desenvolvimento ou progressão da LRA em pacientes com cirrose e infecção bacteriana; b) acurácia de marcadores de função hepática, parâmetros hemodinâmicos, marcadores inflamatórios e testes laboratoriais de lesão renal tradicionalmente utilizados na prática clínica na predição do desenvolvimento ou progressão da LRA em pacientes com cirrose e infecção bacteriana; c) acurácia de marcadores de disfunção hemodinâmica em cirrose (atividade plasmática de renina e noradrenalina sérica) na predição de resposta ao tratamento combinado com albumina e terlipressina em pacientes com diagnóstico estabelecido de SHR; d) acurácia de marcadores de função hepática, parâmetros hemodinâmicos, marcadores inflamatórios e testes laboratoriais de lesão renal tradicionalmente utilizados na prática clínica na predição de resposta ao tratamento combinado com albumina e terlipressina em pacientes com diagnóstico estabelecido de SHR; e) comparar o conceito tradicional de LRA em cirrose com a nova classificação ICA-AKI para predizer mortalidade intra-hospitalar, em 30 e 90 dias em pacientes com cirrose e infecção bacteriana; f) acurácia do NGAL para predizer mortalidade intra-hospitalar em pacientes com cirrose e infecção bacteriana. PACIENTES E MÉTODOS: Critérios de inclusão: a) cirrose; b) ascite e/ou hidrotórax hepático; c) idade maior que 18 anos; d) concordância em participar no estudo; e) LRA e/ou infecção bacteriana. Critérios de exclusão: a) comorbidades graves; b) choque; c) nefropatia intrínseca; d) uso de drogas nefrotóxicas; e) diálise prévia; f) transplante hepático. Foram coletadas amostras de urina para dosagem de NGAL e sangue para dosagem de atividade plasmática de renina e noradrenalina sérica no momento da inclusão do paciente no estudo. Os pacientes com SHR receberam o tratamento padrão atual com albumina e terlipressina. RESULTADOS: Foram incluídos 199 pacientes: 179 com infecção bacteriana para avaliação de desenvolvimento ou progressão da LRA e 58 com SHR para avaliação da resposta ao tratamento (38 pacientes foram avaliados nas duas partes do estudo). O NGAL urinário apresentou associação com a progressão da LRA (AUC: 0,67; p=0,002), mas não com o seu desenvolvimento (p=0,973). Outras variáveis associadas à progressão da LRA foram INR (p=0,033), MELD (p=0,012), FEUr (p=0,026) e relação proteinúria/creatinina urinária (p=0,023). Houve associação entre NGAL urinário e a resposta ao tratamento combinado com albumina e terlipressina em pacientes com SHR (AUC: 0,70; p=0,007). Outras variáveis associadas à resposta ao tratamento da SHR foram INR (p=0,028), MELD (p=0,004) e relação proteinúria/creatinina urinária (p=0,003). Combinando o MELD com o NGAL urinário foi possível identificar subgrupos de pacientes com taxas de resposta ao tratamento com albumina e terlipressina distintas (9,1% x 48,1% x 80,0%, p < 0,001). Tanto o conceito tradicional de LRA na cirrose quanto a classificação ICA-AKI foram capazes de predizer mortalidade intra-hospitalar, em 30 e 90 dias (p < 0,05). O NGAL urinário também foi capaz de predizer mortalidade intra-hospitalar (AUC: 0,71; p < 0,001). CONCLUSÕES: a) NGAL urinário aumentado foi associado à progressão da LRA em pacientes com cirrose e infecção bacteriana; b) atividade plasmática de renina e noradrenalina sérica não se correlacionaram ao desenvolvimento ou progressão da LRA em pacientes com cirrose e infecção bacteriana; c) NGAL urinário foi preditor de resposta ao tratamento combinado com albumina e terlipressina em pacientes com SHR; d) atividade plasmática de renina e noradrenalina sérica não se correlacionaram à resposta ao tratamento combinado com albumina e terlipressina em pacientes com SHR; e) tanto o conceito tradicional de LRA em cirrose quanto a classificação ICA-AKI mostraram-se adequados para predizer mortalidade intra-hospitalar, em 30 e 90 dias em pacientes com cirrose e infecção bacteriana; f) NGAL urinário aumentado foi associado à maior mortalidade intra-hospitalar em pacientes com cirrose e infecção bacteriana / INTRODUCTION: Acute kidney injury (AKI) is a frequent complication of cirrhosis, and is often triggered by bacterial infection. The mortality of patients with cirrhosis and AKI varies from 10 to 100%, depending on the stage of cirrhosis, etiology and progression of AKI, and treatment. Patients with AKI that progresses have a higher in-hospital mortality than those with AKI that does not progress. AKI diagnostic criteria are based on serum creatinine. However, this biomarker has limited diagnostic accuracy, taking up to 48 hours to rise, and does not distinguish the etiology of AKI. This latter limitation is particularly important in patients with suspected hepatorenal syndrome (HRS), because treatment involves high cost medication (albumin and terlipressin) with limited efficacy. NGAL (neutrophil gelatinase-associated lipocalin) is a biomarker of renal tubular necrosis which has been proposed as a more accurate AKI biomarker in cirrhosis because it rises earlier than creatinine and its urinary levels vary according to the etiology of AKI. OBJECTIVES: The primary endpoints were the establishment of the accuracy of urinary NGAL to predict: a) development or progression of AKI in patients with cirrhosis and bacterial infection; b) response to treatment with albumin and terlipressin in patients with diagnosed HRS. The secondary endpoints were: a) accuracy of biomarkers of hemodynamic dysfunction in cirrhosis (renin plasma activity and serum noradrenaline) to predict AKI development or progression in patients with cirrhosis and bacterial infection; b) accuracy of biomarkers of hepatic function, hemodynamics, inflammation and kidney injury routinely used in clinical practice to predict AKI development or progression in patients with cirrhosis and bacterial infection; c) accuracy of biomarkers of hemodynamic dysfunction in cirrhosis (renin plasma activity and serum noradrenaline) to predict response to treatment with albumin and terlipressin in patients with diagnosis of HRS; d) accuracy of biomarkers of hepatic function, hemodynamics, inflammation and kidney injury routinely used in clinical practice to predict response to treatment with albumin and terlipressin in patients with diagnosis of HRS; e) compare the traditional definition of AKI in cirrhosis with the new classification ICA-AKI to predict in-hospital, 30-day and 90-day mortality in patients with cirrhosis and bacterial infection. f) accuracy of urinary NGAL in predicting in-hospital mortality in patients with cirrhosis and bacterial infection. PATIENTS AND METHODS: Inclusion criteria: a) diagnosis of cirrhosis; b) presence of ascites and/or hepatic hydrothorax; c) age over 18 years old; d) consent to participate in the study; e) AKI and/or bacterial infection. Exclusion criteria: a) severe systemic comorbidities; b) shock; c) intrinsic nephropathy; d) nephrotoxic drug use; e) previous dialysis; f) liver transplantation recipient. Urine and blood samples were collected for urinary NGAL and renin plasma activity and serum noradrenaline measurement at the inclusion. Patients with HRS received standard treatment with albumin and terlipressin. RESULTS: 199 patients were included: 179 with bacterial infection for the analysis of AKI development or progression and 58 with HRS for the analysis of response to treatment (38 patients were analyzed in both parts of the study). Urinary NGAL was associated with AKI progression (AUC: 0.67, p=0.002), but not with AKI development (p=0.973). Other variables associated with AKI progression were INR (p=0.003), MELD (p=0.012), FEUr (p=0.026) and proteinuria/urinary creatinine ratio (p=0.023). There was also an association of urinary NGAL with response to HRS treatment with albumin and terlipressin (AUC: 0.70, p=0.007). Other variables associated with response to HRS treatment were INR (p=0.028), MELD (p=0.004) and proteinuria/urinary creatinine ratio (p=0.003). Combining MELD and urinary NGAL we could identify subgroups of patients with distinct response rates to treatment with albumin and terlipressin (9.1% x 48.1% x 80.0%, p < 0.001). Both the traditional definition of AKI in cirrhosis and the classification ICA-AKI predicted in-hospital, 30-day and 90-day mortality (p < 0.05). Urinary NGAL was also associated with in-hospital mortality (AUC: 0.71, p < 0.001). CONCLUSIONS: a) High urinary levels of NGAL were associated with AKI progression in patients with cirrhosis and bacterial infection; b) renin plasma activity and serum noradrenaline were not associated with AKI development or progression in patients with cirrhosis and bacterial infection; c) urinary NGAL was associated with response to combined treatment with albumin and terlipressin in patients with HRS; d) renin plasma activity and serum noradrenaline were not associated with response to combined treatment with albumin and terlipressin in patients with HRS; e) both traditional definition ok AKI in cirrhosis and ICA-AKI classification were able to predict in-hospital, 30-day and 90-day mortality in patients with cirrhosis and bacterial infection; f) high urinary levels of NGAL were associated with in-hospital mortality in patients with cirrhosis and bacterial infection

CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / A sepse neonatal à atualmente a infecÃÃo mais freqÃente e importante causa de Ãbito de RN internados nas UTIN de paÃses desenvolvidos. Para conhecer a dimensÃo desse problema em um Hospital UniversitÃrio de atendimento terciÃrio localizado no Nordeste do Brasil, foi realizado um estudo de coorte retrospectivo de todos as crianÃas que nasceram e foram admitidas na UTIN no perÃodo de outubro de 1997 a abril de 1998. Uma coorte de 422 pares de recÃm-nascidos e suas respectivas mÃes foi formada; os RN foram seguidos do nascimento à alta ou Ãbito na UTIN ou atà a idade de 28 dias enquanto internados na UTIN. Ao todo, cerca de 34 variÃveis maternas, do neonato e procedimentos hospitalares foram pesquisadas em cada membro da coorte. Os testes estatÃsticos utilizados foram: Teste do Qui-quadrado e o Teste exato de FISCHER, cÃlculo do risco relativo com os respectivos intervalos de confianÃa. Em seguida procedeu-se a anÃlise multivariada com transformaÃÃo para logÃstica dos fatores mais significativos (p<0,05). Ao final, cinco fatores foram selecionados como preditores independentes da sepse neonatal: cateterizaÃÃo venosa central (OR=8,7, IC95%=2,3 a 32,6), faixa ponderal 1000 a 1499g (OR=4,8, IC95%=2,3 a 9,9), transfusÃo de hemoderivados (OR=3,6, IC95%=1,8 a 7,4), gravidez Ãnica (OR=2,3, IC95%=1,0 a 5,4) e faixa ponderal 1500 a 2499g (OR=2,3, IC95%=1,3 a 4,0). A incidÃncia de sepse na coorte foi de 40,4 para cada 100 RN admitidos (167/413). As bactÃrias mais prevalentes dos casos confirmados foram os bacilos gram-negativos; 67% dos episÃdios surgiram nos seis primeiros dias de vida. A internaÃÃo dos RN com sepse foi 4,3 vezes superior a internaÃÃo dos RN nÃo acometidos. A mortalidade global na UTIN foi de 25,59 para cada 100 RN admitidos, enquanto a letalidade pelo desfecho foi de 41,31%, com risco relativo de morte por sepse de 2,8. Este estudo poderà ser Ãtil para futuras estratÃgias com vistas a diminuir a morbimortalidade por sepse neonatal. / OBJECTIVE: Neonatal sepsis is currently the most frequent infection and an important cause of death among the newborns admitted at NICU. In order to evaluate the extension of this problem in a tertiary care University Hospital of Northeastern Brazil, a retrospective cohort survey was carried out on all inborn and admitted infants at the Assis Chateaubriand NICU from October 1997 to April 1998. METHOD: the survey design was a retrospective cohort carried out on all inborn infants admitted at the Neonatal Intensive Care Unit during seven consecutive months; 422 newborns were enrolled in the study and each one was followed up from birth to discharge from NCIU or death at the NICU. To compare the levels of the risk factors, two groups were formed: one by the all subjects who developed the outcome and another by all those who did not to. Each member of the cohort was investigated for 34 potential predictors variables concerning mothers factors, neonates factors and hospital procedures. In case of presence of sepsis, the variables were measured just up to the outcome. Standard National Nosocomial Infection Surveillance (NNIS-CDC) definitions of sepsis were used. Chi Square and Fischerâs exact tests were applied for comparison of frequencies; relative risk (RR) with their respective confidence interval of 95% (CI95%) was calculated. Subsequently, a multivariate analysis was done using logistic regression of most significant factors (OR). The level of statistical significance considered was p=0,05. RESULTS: The cohort sepsis incidence was 40,4 for each hundred of newborn admitted at NICU. The bacterias more prevalent of the confirmed cases were the gram-negative bacilli. Most sepsis episodes appeared in the first six days of life (67%). The time of NICU hospitalization of the sick newborn was 4,3 times longer compared to that non-sick newborn. Five factors were selected as independent predictors for neonatal sepsis: central venous catheter (OR=8,7, CI95%=2,31 to 32,69, p=0,001), birth weight of 1000-1499g (OR=4,8, CI95%=2,39 to 9,97, p=0,000), blood transfusions (OR=3,6, CI95%=1,81 to 7,45, p=0,003), singular gestation (OR=2,3, CI95%=1,04 to 5,44, p=0,04) and birth weight of 1500<2500g (OR=2,3, CI95%=1,34 to 4,04, p=0,002). Global mortality reached 25,59% of the cohort. Mortality associated to sepsis was 41,31% with Relative Risk for death = 2,8. CONCLUSION: neonatal sepsis incidence and mortality rates found are higher than in developed countries rates. Birth weight under 2500g, singular gestation, central venous catheter and blood transfusions proved be independent predictors related to neonatal sepsis. This study may contribute for the future strategies for reduction of neonatal sepsis rates and its sequels in our hospital.