41 research outputs found
Isolamento de amebas de vida livre a partir de água mineral engarrafada
Amoebae of the genera Vahlkampfia, Glaeseria, Acanthamoeba, Filamoeba, Amoeba, Platyamoeba and Hartmanella were isolated from ten different brands of bottled mineral water used in Rio de Janeiro. Of these brands, only one was negative after an incubation period of twenty days, while the others were all positive for free living amoebae. The results are discussed as an indicator of the quality of commercially used mineral water and it is stressed that some of these microorganisms are potentially pathogenic.Foram isoladas amebas dos gêneros Vahlkampfia, Glaeseria, Acanthamoeba, Filamoeba, Amoeba, Platyamoeba e Hartmanella de dez diferentes marcas de água mineral engarrafadas, servidas no Rio de Janeiro, RJ (Brasil). Somente uma das marcas foi negativa para protozoários, enquanto que de todas as outras foram isoladas amebas de vida livre. O significado desses resultados é discutido como um indicador de qualidade da água mineral usada comercialmente, destacando-se o fato de que alguns desses microorganismos são potencialmente patogênicos
A historical and proteomic analysis of botulinum neurotoxin type/G
<p>Abstract</p> <p>Background</p> <p><it>Clostridium botulinum </it>is the taxonomic designation for at least six diverse species that produce botulinum neurotoxins (BoNTs). There are seven known serotypes of BoNTs (/A through/G), all of which are potent toxins classified as category A bioterrorism agents. BoNT/G is the least studied of the seven serotypes. In an effort to further characterize the holotoxin and neurotoxin-associated proteins (NAPs), we conducted an <it>in silico </it>and proteomic analysis of commercial BoNT/G complex. We describe the relative quantification of the proteins present in the/G complex and confirm our ability to detect the toxin activity <it>in vitro</it>. In addition, we review previous literature to provide a complete description of the BoNT/G complex.</p> <p>Results</p> <p>An in-depth comparison of protein sequences indicated that BoNT/G shares the most sequence similarity with the/B serotype. A temperature-modified Endopep-MS activity assay was successful in the detection of BoNT/G activity. Gel electrophoresis and in gel digestions, followed by MS/MS analysis of/G complex, revealed the presence of four proteins in the complexes: neurotoxin (BoNT) and three NAPs--nontoxic-nonhemagglutinin (NTNH) and two hemagglutinins (HA70 and HA17). Rapid high-temperature in-solution tryptic digestions, coupled with MS/MS analysis, generated higher than previously reported sequence coverages for all proteins associated with the complex: BoNT 66%, NTNH 57%, HA70 91%, and HA17 99%. Label-free relative quantification determined that the complex contains 30% BoNT, 38% NTNH, 28% HA70, and 4% HA17 by weight comparison and 17% BoNT, 23% NTNH, 42% HA70, and 17% HA17 by molecular comparison.</p> <p>Conclusions</p> <p>The <it>in silico </it>protein sequence comparisons established that the/G complex is phenetically related to the other six serotypes of <it>C. botulinum</it>. Proteomic analyses and Endopep-MS confirmed the presence of BoNT and NAPs, along with the activity of the commercial/G complex. The use of data-independent MS<sup>E </sup>data analysis, coupled to label-free quantification software, suggested that the weight ratio BoNT:NAPs is 1:3, whereas the molar ratio of BoNT:NTNH:HA70:HA17 is 1:1:2:1, within the BoNT/G progenitor toxin.</p
Mass Spectrometric Analysis of Multiple Pertussis Toxins and Toxoids
Bordetella pertussis (Bp) is the causative agent of pertussis, a vaccine preventable disease occurring primarily in children. In recent years, there has been increased reporting of pertussis. Current pertussis vaccines are acellular and consist of Bp proteins including the major virulence factor pertussis toxin (Ptx), a 5-subunit exotoxin. Variation in Ptx subunit amino acid (AA) sequence could possibly affect the immune response. A blind comparative mass spectrometric (MS) analysis of commercially available Ptx as well as the chemically modified toxoid (Ptxd) from licensed vaccines was performed to assess peptide sequence and AA coverage variability as well as relative amounts of Ptx subunits. Qualitatively, there are similarities among the various sources based on AA percent coverages and MS/MS fragmentation profiles. Additionally, based on a label-free mass spectrometry-based quantification method there is differential relative abundance of the subunits among the sources
Prevalence of intestinal microsporidiosis in Human Immunodeficiency Virus-infected patients with diarrhea in major United States cities
To determine the prevalence of intestinal microsporidiosis in HIV-infected patients, we performed a prospective study of HIV-infected patients with diarrheal illnesses in three US hospitals and examined an observational database of HIV-infected patients in 10 US cities. Among 737 specimens from the three hospitals, results were positive for 11 (prevalence 1.5%); seven (64%) acquired HIV through male-to-male sexual contact, two (18%) through male-to-male sexual contact and injection drug use, and one (9%) through heterosexual contact; one (9%) had an undetermined mode of transmission. Median CD4 count within six months of diagnosis of microsporidiosis was 33 cells/µL (range 3 to 319 cells/µL). For the national observational database (n = 24,098), the overall prevalence of microsporidiosis was 0.16%. Prevalence of microsporidiosis among HIV-infected patients with diarrheal disease is low, and microsporidiosis is most often diagnosed in patients with very low CD4+ cell counts. Testing for microsporidia appears to be indicated, especially for patients with very low CD4+ cell counts.Para determinar a prevalência de microsporidiose intestinal em pacientes infectados pelo HIV foi realizado um estudo prospectivo em três hospitais dos Estados Unidos da América do Norte (EUA) e analizada uma base de dados nacional composta de dados coletados de pacientes infectados pelo HIV em 10 cidades dos EUA. De um total de 737 amostras de fezes de pacientes infectados pelo HIV que apresentavam diarréia, amostras de 11 pacientes (prevalência de 1,5%) foram positivas para microsporídios. Todos os positivos eram do sexo masculino e, entre eles, sete (64%) pacientes adquiriram a infecção pelo HIV através de relação homossexual, dois (18%) através de relação sexual e drogas injetáveis e um (9%) através de contato heterosexual, enquanto que em um paciente o modo de transmissão do HIV não foi determinado. A contagem média de linfócitos CD4 realizada até seis meses do diagnóstico de microsporidiose foi de 33 células/microlitro (3 a 319 células/microlitro). A análise da base de dados nacional (n = 24.098) mostrou uma prevalência de microsporidiose de 0,16%. A prevalência de microsporidiose em pacientes HIV-positivos com diarréia é baixa. Entretando, como a microsporidiose é mais frequentemente diagnosticada em pacientes com contagens de CD4 muito baixas, a indicação de pesquisa de microsporídios é justificada, especialmente para estes pacientes
Aspectos clínicos e diagnósticos da microsporidiose intestinal em pacientes com infecção pelo HIV e diarréia crônica, no Rio de Janeiro, Brasil
The objectives of this study were to determine both the prevalence of microsporidial intestinal infection and the clinical outcome of the disease in a cohort of 40 HIV-infected patients presenting with chronic diarrhea in Rio de Janeiro, Brazil. Each patient, after clinical evaluation, had stools and intestinal fragments examined for viral, bacterial and parasitic pathogens. Microsporidia were found in 11 patients (27.5%) either in stools or in duodenal or ileal biopsies. Microsporidial spores were found more frequently in stools than in biopsy fragments. Samples examined using transmission electron microscopy (n=3) or polymerase chain reaction (n=6) confirmed Enterocytozoon bieneusi as the causative agent. Microsporidia were the only potential enteric pathogens found in 5 of the 11 patients. Other pathogens were also detected in the intestinal tract of 21 patients, but diarrhea remained unexplained in 8. We concluded that microsporidial infection is frequently found in HIV infected persons in Rio de Janeiro, and it seems to be a marker of advanced stage of AIDS.Os objetivos deste estudo foram determinar a prevalência e o prognóstico clínico da infecção por microsporídios em uma coorte de 40 pacientes com infecção pelo HIV e diarréia crônica na cidade do Rio de Janeiro, Brasil. Cada paciente teve suas fezes e fragmentos de intestino examinados para a pesquisa de CMV, bactérias e parasitos. A prevalência de microsporidiose foi de 27,5% (n=11). Esporos de microsporídios foram encontrados com maior frequência no exame direto das fezes do que em biópsias de intestino delgado. A microscopia eletrônica de transmissão e a reação de polimerase em cadeia (PCR) identificaram Enterocytozoon bieneusi, respectivamente, em 3 e 6 amostras examinadas, confirmando a espécie como único agente causal. Nenhum outro microrganismo patogênico, além dos microsporídios, foi detectada em 5 dos pacientes com diarréia. Outros parasitos foram encontrados no trato digestivo de 21 pacientes, enquanto que em 8 a etiologia da diarréia não foi definida. Concluímos que a infecção por microsporídios pode ser freqüentemente encontrada em indivíduos infectados pelo HIV no Rio de Janeiro
Botulinum Neurotoxin Detection and Differentiation by Mass Spectrometry
A new rapid, mass spectrometry-based method to detect and differentiate botulinal neurotoxins is described
Extraction and Inhibition of Enzymatic Activity of Botulinum Neurotoxins/A1, /A2, and /A3 by a Panel of Monoclonal Anti-BoNT/A Antibodies
Botulinum neurotoxins (BoNTs) are extremely potent toxins that are capable of causing death or respiratory failure leading to long-term intensive care. Treatment includes serotype-specific antitoxins, which must be administered early in the course of the intoxication. Rapidly determining human exposure to BoNT is an important public health goal. In previous work, our laboratory focused on developing Endopep-MS, a mass spectrometry-based endopeptidase method for detecting and differentiating BoNT/A–G serotypes in buffer and BoNT/A, /B, /E, and /F in clinical samples. We have previously reported the effectiveness of antibody-capture to purify and concentrate BoNTs from complex matrices, such as clinical samples. Because some antibodies inhibit or neutralize the activity of BoNT, the choice of antibody with which to extract the toxin is critical. In this work, we evaluated a panel of 16 anti-BoNT/A monoclonal antibodies (mAbs) for their ability to inhibit the in vitro activity of BoNT/A1, /A2, and /A3 complex as well as the recombinant LC of A1. We also evaluated the same antibody panel for the ability to extract BoNT/A1, /A2, and /A3. Among the mAbs, there were significant differences in extraction efficiency, ability to extract BoNT/A subtypes, and inhibitory effect on BoNT catalytic activity. The mAbs binding the C-terminal portion of the BoNT/A heavy chain had optimal properties for use in the Endopep-MS assay
Evaluation of the effect of phenolic-rich extracts from jaboticaba-sabará (Plinia jaboticaba (Vell.) Berg) in prevention of obesity and type 2 diabetes mellitus.
A jabuticaba-sabará (Plinia jaboticaba (Vell.) Berg) é uma fruta nativa da Mata Atlântica que possui alto teor de antocianinas, proantocianidinas e elagitaninos, fenólicos associados com diversos benefícios à saúde. O objetivo deste trabalho foi avaliar o efeito de dois extratos ricos em compostos fenólicos da jabuticaba-sabará sobre a massa corporal e o metabolismo da glicose e dos lipídios de camundongos alimentados com dieta rica em lipídios e sacarose (HLS). Foram utilizados 40 camundongos machos C57BL/6J com oito semanas de idade e alimentados com ração padrão para camundongos ou dieta HLS durante oito semanas. Os animais foram divididos aleatoriamente em quatro grupos de dez. Os dois primeiros grupos receberam, respectivamente, ração padrão para camundongos ou dieta HLS e água ad libitum, sendo denominados, nesta ordem, grupo controle (Ct) e grupo HF. Os dois últimos grupos foram alimentados com dieta HLS recebendo, por gavagem, os extratos ricos em compostos fenólicos, sendo denominados grupo C18 e PA, respectivamente. Para o grupo C18 foi administrado o extrato obtido por extração em fase sólida (EFS) em colunas de octadecilsilano (C18), possuindo maior concentração de taninos. O grupo PA recebeu o extrato obtido por EFS em colunas de poliamida (PA), resultando em um extrato com menor concentração de taninos em relação ao extrato C18. A dose de fenólicos administrada aos animais foi de 50 mg equivalentes de ácido gálico (EAG)/kg de massa corporal para ambos os grupos. Na sexta semana foi realizado o teste de tolerância à insulina (ITT) e, na sétima, o teste oral de tolerância à glicose (OGTT). Além da massa corporal, os animais foram também avaliados quanto a glicemia, insulinemia e perfil lipídico (colesterol total, HDL, LDL e triacilgliceróis). Os grupos suplementados apresentaram menor ganho de massa dos tecidos adiposos brancos em comparação ao grupo HF (43% para o grupo C18 e 28% para o grupo PA). Além disto, ambos os extratos atenuaram os níveis de glicose e o extrato C18 melhorou os níveis de insulina plasmática, colesterol total e triacilgliceróis hepáticos. Portanto, extratos ricos em compostos fenólicos da jabuticaba-sabará foram eficientes na prevenção do ganho de massa corporal, evitando o crescimento excessivo dos tecidos adiposos brancos, de altos níveis de glicose, insulina, colesterol total e triacilgliceróis hepáticos em camundongos alimentados com dieta rica em lipídios e sacarose.Sabará jaboticaba is a Brazilian Atlantic Forest fruit rich in anthocyanins, proanthocyanidins and ellagitannins, phenolic compounds that have been associated to several benefits to health. This work aimed to evaluate the effect of the administration of two phenolic-rich extracts from Sabará jaboticaba on body weight gain and on glucose and lipid metabolism of high-fat-sucrose-fed mice. Forty 8-week old male C57BL/6J mice were fed a low-fat chow diet or a high fat, high-sucrose (HFHS) diet for 8 weeks. The animals were randomly divided into four groups of ten mice each. The first two groups received, respectively, a low-fat chow diet or a HFHS diet and water ad libitum and were nominated, in order, control (Ct) and HF group. The last two groups were fed a HFHS diet and received by gavage the phenolic-rich extracts, being respectively nominated C18 and PA group. The C18 group received an extract obtained by solid phase extraction (SPE) in octadecylsilane (C18) column, therefore the most concentrated in tannins. The PA group received an extract obtained by SPE in polyamide (PA) column, therefore less concentrated in tannins. The dose of phenolics administered to animals was of 50 mg acid gallic equivalent (GAE)/kg body weight, for both groups. The insulin tolerance test (ITT) was performed in the sixth week and the oral glucose tolerance test (OGTT) in the seventh week. In addition, the animals were assessed for glycaemia, insulinemia and lipid profile (total-, HDL-, LDL-cholesterol and triacylglycerols). The supplemented groups had lower white adipose tissue gain than HF group (43% for the C18 group and 28% for the PA group). In addition, both extracts attenuated hyperglycemia and the C18 extract improved the plasmatic insulin levels, total cholesterol and hepatic triacylglycerol content. Thus, phenolic-rich extracts from Sabará jaboticaba were effective in preventing body weight gain, avoiding the overgrowth of white adipose tissues, and high levels of glucose, insulin, total cholesterol and hepatic triacylglycerols in HFHS-fed C57BL/6J mice
Efeito dos compostos fenólicos da jabuticaba Sabará (Plinia jaboticaba (Vell.) Berg) na redução dos riscos à saúde causados pela obesidade
Sabara jaboticaba (Plinia jaboticaba (Vell.) Berg) is a Brazilian native fruit from Atlantic Forest, rich in polyphenols and appreciated for consumption both in natura and in various preparations. This study aimed to evaluate whether phenolic compounds of Sabara jaboticaba, in the form of phenolic extract (PEJ), can reduce the health risks caused by obesity and associated health problems induced by a fat-sucrose-rich diet (HFSD) in C57BL/6J mice. Initially, for 14 weeks, 66 8-week-old male mice were randomly distributed into two groups: negative control (CH), fed with standard AIN96M diet and water ad libitum; positive control (HFS), fed with HFSD and water ad libitum. At the end of this stage, 10 animals from each group were euthanized under anesthesia and their organs and tissues collected. The remaining animals were redistributed into four groups for another 14 weeks: group CH, fed a standard diet and water; HFS group, fed with HFSD and water; PEJ1 group, fed with HFSD and PEJ at the dose of 50 mg equivalent of gallic acid (GAE)/kg of body weight (BW); group J100 fed with HFSD and PEJ at the dose of 100 mg GAE/kg BW. Food intake, BW, and fasting blood glucose (FBG) were measured weekly and water (CH and HFS) or PEJ (PEJ1 and PEJ2) were daily administered. In the 26th week the intraperitoneal insulin tolerance test (ipITT) was performed, in the 27th, the oral glucose tolerance test (oGTT), and, in the 28th, the analyzes related to energy homeostasis. At the end of the experiment, the animals were euthanized under anesthesia and their organs and tissues were collected. When compared to the HFS group, animals that received PEJ showed decrease in BW gain of approx. 30% and of approx. 45% in the gain of total white adipose tissues (WAT). In addition, the PEJ groups showed less hypertrophied adipocytes. Inflammation markers were significantly reduced in both treated groups. The FBG was approx. 13% lower for the PEJ groups compared to the HFS group. In addition, the mean values of ipITT, oGTT, insulin and HOMA-IR demonstrated that PEJ increased insulin sensitivity and decreased glucose intolerance. GLUT4 expression in the muscle was also increased in the treated groups. The fecal lipid content was lower in the PEJ groups when compared to the HFS group, suggesting that PEJ inhibited pancreatic lipase activity both in vitro and in vivo. In the PEJ groups, the levels of total cholesterol, LDL and NEFA were reduced and those of HDL increased. The hepatic concentration of TAG was also reduced by PEJ. Energy expenditure and UCP1 expression were higher for both supplemented groups when compared to the HFS group. PEJ positively altered the intestinal microbiota and the analysis of metabolites showed that animals treated with PEJ had different metabolomic profile. Together, these results demonstrated that polyphenols from jaboticaba may be used as adjuvants against obesity and associated health problems.A jabuticaba Sabará (Plinia jaboticaba (Vell.) Berg) é um fruto nativo da Mata Atlântica brasileira, rico em polifenóis e apreciado para o consumo tanto in natura quanto em preparos variados. O objetivo deste trabalho foi avaliar se compostos fenólicos da jabuticaba Sabará, na forma de extrato fenólico (PEJ), são capazes de reduzir os riscos à saúde causados pela obesidade e problemas de saúde associados induzidos por uma dieta rica em lipídios e sacarose (HFSD) em camundongos C57BL/6J. Inicialmente, durante 14 semanas, 66 animais machos com oito semanas de vida foram distribuídos aleatoriamente em dois grupos: controle negativo (CH), alimentado com dieta padrão AIN96M e água ad libitum; controle positivo (HFS), alimentado com HFSD e água ad libitum. Ao final desta etapa, 10 animais de cada grupo foram eutanasiados sob anestesia e seus órgãos e tecidos coletados. Os animais restantes foram redistribuídos em quatro grupos por mais 14 semanas: grupo CH, alimentado com dieta padrão e água; grupo HFS, alimentado com HFSD e água; grupo PEJ1, alimentado com HFSD e PEJ na dose de 50 mg equivalente de ácido gálico (EAG)/kg de massa corporal (m.c.); grupo J100 alimentado com HFSD e PEJ na dose de 100 mg EAG/kg m.c. O consumo de ração, a massa corporal e a glicemia de jejum (FBG) foram medidos semanalmente e as gavagens de água (CH e HFS) ou PEJ (PEJ1 e PEJ2) foram realizadas diariamente. Na 26ª semana foi realizado o teste intraperitoneal de tolerância à insulina (ipITT), na 27ª o teste oral de tolerância à glicose (oGTT) e na 28ª as análises relacionadas a homeostase energética. Ao final do experimento os animais foram eutanasiados sob anestesia e seus órgãos e tecidos coletados. Quando comparados ao grupo HFS, animais que receberam o PEJ apresentaram ganho de massa corporal aprox. 30% menor e aprox. 45% menos massa total de tecidos adiposos brancos (TAB). Além disso, os grupos PEJ apresentaram adipócitos menos hipertrofiados. Marcadores de inflamação foram significativamente reduzidos em ambos os grupos tratados. A FBG foi aprox. 13% inferior para os grupos PEJ em relação ao grupo HFS. Além disso, os valores médios de ipITT, oGTT, insulina e HOMA-IR demonstraram que o PEJ aumentou a sensibilidade à insulina e diminuiu a intolerância à glicose. A expressão do GLUT4 no músculo estava aumentada nos grupos tratados. O conteúdo lipídico fecal dos grupos PEJ foi superior ao do grupo HFS, sugerindo que, assim como ocorreu in vitro, o extrato inibiu a atividade da lipase pancreática in vivo. Os níveis de colesterol total (PEJ1), LDL e NEFA foram reduzidos e os de HDL aumentados. A concentração hepática de TAG também foi reduzida pelo PEJ. O gasto energético e a expressão de UCP1 foram superiores para ambos os grupos suplementados quando comparados ao grupo HFS. PEJ alterou positivamente a microbiota intestinal e a análise de metabólitos mostrou que os animais tratados com PEJ possuíam perfil metabolômico diferente. Em conjunto, estes resultados demonstraram que os CFJS podem ser usados como adjuvantes no combate a obesidade e problemas de saúde associados