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1.
Bioresour Technol ; 247: 829-837, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30060419

RESUMO

The present work assessed the feasibility of used cooking oil as a low cost carbon source for rhamnolipid biosurfactant production employing the strain Burkholderia thailandensis. According to the results, B. thailandensis was able to produce rhamnolipids up to 2.2 g/L, with the dominant congener being the di-rhamnolipid Rha-Rha-C14-C14. Rhamnolipids had the ability to reduce the surface tension to 37.7 mN/m and the interfacial tension against benzene and oleic acid to 4.2 and 1.5 mN/m, while emulsification index against kerosene reached up to 64%. The ability of B. thailandensis to accumulate intracellular biopolymers, in the form of polyhydroxyalkanoates (PHA), was also monitored. Polyhydroxybutyrate (PHB) was accumulated simultaneously and consisted of up to 60% of the cell dry weight. PHB was further characterized in terms of its molecular weight and thermal properties. This is the first study reporting the simultaneous production of polyhydroxyalkanoates and rhamnolipids by the non-pathogen rhamnolipid producer B. thailandensis.


Assuntos
Burkholderia , Glicolipídeos/metabolismo , Poli-Hidroxialcanoatos/metabolismo , Reciclagem , Culinária , Óleos , Pseudomonas aeruginosa
2.
Hum Immunol ; 73(6): 661-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22507624

RESUMO

Accumulating evidence indicates that genetic background influences the outcome of sepsis, which despite medical advances continues to be a major cause of morbidity and mortality. This study aimed to evaluate the influence of SNPs LTA +252A>G, TNF-863C>A and TNF-308G>A on susceptibility to sepsis, acute respiratory distress syndrome (ARDS), septic shock and sepsis mortality. A prospective case-control study was carried out in a Brazilian pediatric intensive care unit and included 490 septic pediatric patients submitted to mechanical ventilation and 610 healthy children. No SNP association was found with respect to sepsis susceptibility. Nevertheless, a haplotype was identified that was protective against sepsis (+252A/-863A/-308G; OR=0.65; p=0.03). We further observed protection against ARDS in TNF-308 GA genotype carriers (OR=0.29; p=0.0006) and -308A allele carriers (OR=0.40; p=0.003). In addition, increased risk for ARDS was detectable with the TNF-863 CA genotype (OR=1.83; p=0.01) and the -863A carrier status (OR=1.82; p=0.01). After stratification according to age, this outcome remained significantly associated with the -308GA genotype in infants. Finally, protection against sepsis-associated mortality was found for the TNF-308 GA genotype (OR=0.22; p=0.04). Overall, our findings document a protective effect of the TNF-308 GA genotype for the ARDS and sepsis mortality outcomes, further providing evidence for an increased risk of ARDS associated with the TNF-863 CA genotype. Trial registration (www.clinicaltrials.gov): NCT00792883.


Assuntos
Linfotoxina-alfa/genética , Polimorfismo de Nucleotídeo Único , Síndrome do Desconforto Respiratório/genética , Sepse/genética , Fator de Necrose Tumoral alfa/genética , Adolescente , Alelos , Brasil , Estudos de Casos e Controles , Criança , Pré-Escolar , Estado Terminal , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Unidades de Terapia Intensiva Pediátrica , Linfotoxina-alfa/imunologia , Masculino , Estudos Prospectivos , Síndrome do Desconforto Respiratório/imunologia , Síndrome do Desconforto Respiratório/mortalidade , Risco , Sepse/imunologia , Sepse/mortalidade , Taxa de Sobrevida , Fator de Necrose Tumoral alfa/imunologia
3.
Braz J Med Biol Res ; 38(2): 171-83, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15785828

RESUMO

Because low tumor necrosis factor-alpha (TNF-alpha) production has been reported in malnourished children, in contrast with high production of TNF-alpha in experimental protein-energy malnutrition, we reevaluated the production of TNF-alpha in whole blood cultures from children with primary malnutrition free from infection, and in healthy sex- and age-matched controls. Mononuclear cells in blood diluted 1:5 in endotoxin-free medium released TNF-alpha for 24 h. Spontaneously released TNF-alpha levels (mean +/- SEM), as measured by enzyme immunoassay in the supernatants of unstimulated 24-h cultures, were 10,941 +/- 2,591 pg/ml in children with malnutrition (N = 11) and 533 +/- 267 pg/ml in controls (N = 18) (P < 0.0001). TNF-alpha production was increased by stimulation with lipopolysaccharide (LPS), with maximal production of 67,341 +/- 16,580 pg/ml TNF-alpha in malnourished children and 25,198 +/- 2,493 pg/ml in controls (P = 0.002). In control subjects, LPS dose-dependently induced TNF-alpha production, with maximal responses obtained at 2000 ng/ml. In contrast, malnourished patients produced significantly more TNF-alpha with 0.02-200 ng/ml LPS, responded maximally at a 10-fold lower LPS concentration (200 ng/ml), and presented high-dose inhibition at 2000 ng/ml. TNF-alpha production a) was significantly influenced by LPS concentration in control subjects, but not in malnourished children, who responded strongly to very low LPS concentrations, and b) presented a significant, negative correlation (r = -0.703, P = 0.023) between spontaneous release and the LPS concentration that elicited maximal responses in malnourished patients. These findings indicate that malnourished children are not deficient in TNF-alpha production, and suggest that their cells are primed for increased TNF-alpha production.


Assuntos
Transtornos da Nutrição Infantil/sangue , Leucócitos Mononucleares/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Células Sanguíneas/imunologia , Células Sanguíneas/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Criança , Transtornos da Nutrição Infantil/imunologia , Pré-Escolar , Feminino , Humanos , Lactente , Leucócitos Mononucleares/imunologia , Lipopolissacarídeos/imunologia , Masculino
4.
Braz. j. med. biol. res ; 38(2): 171-183, fev. 2005. tab, graf
Artigo em Inglês | LILACS, BVSAM | ID: lil-393653

RESUMO

Because low tumor necrosis factor-alpha (TNF-alpha) production has been reported in malnourished children, in contrast with high production of TNF-alpha in experimental protein-energy malnutrition, we reevaluated the production of TNF-alpha in whole blood cultures from children with primary malnutrition free from infection, and in healthy sex- and age-matched controls. Mononuclear cells in blood diluted 1:5 in endotoxin-free medium released TNF-alpha for 24 h. Spontaneously released TNF-alpha levels (mean ± SEM), as measured by enzyme immunoassay in the supernatants of unstimulated 24-h cultures, were 10,941 ± 2,591 pg/ml in children with malnutrition (N = 11) and 533 ± 267 pg/ml in controls (N = 18) (P < 0.0001). TNF-alpha production was increased by stimulation with lipopolysaccharide (LPS), with maximal production of 67,341 ± 16,580 pg/ml TNF-alpha in malnourished children and 25,198 ± 2,493 pg/ml in controls (P = 0.002). In control subjects, LPS dose-dependently induced TNF-alpha production, with maximal responses obtained at 2000 ng/ml. In contrast, malnourished patients produced significantly more TNF-alpha with 0.02-200 ng/ml LPS, responded maximally at a 10-fold lower LPS concentration (200 ng/ml), and presented high-dose inhibition at 2000 ng/ml. TNF-alpha production a) was significantly influenced by LPS concentration in control subjects, but not in malnourished children, who responded strongly to very low LPS concentrations, and b) presented a significant, negative correlation (r = -0.703, P = 0.023) between spontaneous release and the LPS concentration that elicited maximal responses in malnourished patients. These findings indicate that malnourished children are not deficient in TNF-alpha production, and suggest that their cells are primed for increased TNF-alpha production.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Fator de Necrose Tumoral alfa , Células Sanguíneas/imunologia , Transtornos da Nutrição Infantil/imunologia , Leucócitos Mononucleares/imunologia , Lipopolissacarídeos/imunologia , Estudos de Casos e Controles , Células Cultivadas
5.
Lett Appl Microbiol ; 34(1): 32-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11849489

RESUMO

AIMS: The aim of this study was to investigate the production of ethyl carbamate (EC) precursors by Lactobacillus hilgardii in model and Douro fortified wines and to determine the relationship between these compounds and EC levels in this type of wine. METHODS AND RESULTS: Several model fortified wines and fortified wine inoculated with L. hilgardii were analysed for citrulline and EC formation. A good correlation (R > 0.9) was obtained between citrulline and potential EC (that EC which is formed during heating of sample at 80 degrees C for 48 h). CONCLUSIONS: This correlation allowed us to calculate the potential EC formed during lactic acid bacteria activity in fortified wine. SIGNIFICANCE AND IMPACT OF THE STUDY: A good correlation was obtained (R=0.92) between measured and calculated EC in spoiled fortified wines, citrulline apparently being the main EC precursor produced by Lact. hilgardii thus contributing to the potential EC in this type of wine.


Assuntos
Citrulina/metabolismo , Alimentos Fortificados , Lactobacillus/metabolismo , Uretana/metabolismo , Vinho/microbiologia , Citrulina/análise , Ornitina/análise , Uretana/análise
6.
J Agric Food Chem ; 49(1): 263-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11170587

RESUMO

2,6,6-Trimethylcyclohex-2-ene-1,4-dione (TMCHD), a norisoprenoid with a sweet honey aroma descriptor, is reported for the first time as a minor constituent of single-varietal table and fortified wines from the demarcated Douro region. Olfactory gas chromatography (GC-O) of a volatile wine extract, previously isolated by preparative gas chromatography, indicated the presence of a zone containing an intense honey descriptor. The targeted odor compound was identified by GC-MS, GC-O, and Kovats index. Quantitative analysis using a selected characteristic ion (m/z 96) indicated that young Douro fortified wines from the 1997 vintage contained up to 4 microg/L TMCHD. The sweet honey sensory threshold limit for TMCHD in a model Port wine solution was found to be 25 microg/L. TMCHD is therefore only likely to contribute as a collective element to Port wine aroma. The wine volatile diacetyl was identified as a strong contributor to the sweet caramel aroma descriptor often associated with Port.


Assuntos
Cicloexanos/análise , Diacetil/análise , Odorantes , Vinho/análise , Cromatografia Gasosa/métodos , Cromatografia Gasosa-Espectrometria de Massas , Portugal , Olfato
7.
Rev Soc Bras Med Trop ; 33(3): 313-7, 2000.
Artigo em Português | MEDLINE | ID: mdl-10967601

RESUMO

This case study reports a typical clinical course of cat-scratch disease (CSD) in an infant without epidemiological data and presenting bilateral submandibular lymphadenopathy. The authors describe clinical course, ultrasound images, diagnosis and prognosis. Polymerase chain reaction (PCR) detected and identified B. quintana in lymph node samples. B. henselae currently thought to be the causative agent of CSD was not detected. The PCR assays for B. quintana and B. henselae should be available for the investigation of lymphadenopathy, even if the infant has not had either cat or dog contact.


Assuntos
Bartonella quintana , Doença da Arranhadura de Gato/microbiologia , Feminino , Humanos , Lactente
8.
J Agric Food Chem ; 47(10): 4327-31, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10552810

RESUMO

2,2,6-Trimethylcyclohexanone and ethyl dihydrocinnamate, known sensorial descriptors of rock-rose (Cistus ladaniferus) aroma, are reported as minor constituents of young fortified wines from the Douro Demarcated region (vintage 1997) for the first time. These compounds were respectively identified by GC-MS in two different fractions (A and B) obtained by preparative GC. Quantitative analysis by GC-MS was performed on 14 fortified wines originating from the different Douro subregions. Ethyl dihydrocinnamate was found to be present at concentrations between 2.3 and 6.7 microgram/L, while 2,2,6-trimethylcyclohexanone ranged from 0.05 to 0.4 microgram/L.


Assuntos
Odorantes/análise , Rosales/química , Vinho/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Extratos Vegetais/isolamento & purificação , Portugal , Volatilização
9.
Rev Soc Bras Med Trop ; 32(5): 557-70, 1999.
Artigo em Português | MEDLINE | ID: mdl-10881091

RESUMO

This retrospective study reviews cases of ARDS (Adult Respiratory Distress Syndrome) treated and followed up from October 1988 to December 1990 in the Pediatric Intensive Care Unit of Instituto Fernandes Figueira/FIOCRUZ, Brazil. Clinical, radiological and histopathological features were analyzed and correlated with well defined stages of the disease process. Out of 459 cases, 49 (11%) were selected for further study. In 11 cases, histopathological examination (4 biopsies and 8 autopsies) was performed and then classified into one of the following phases: exsudative, cellular proliferative and late fibrotic. The work emphasizes the need for further clinical and experimental studies in order to define the mechanisms and the impact of this Syndrome in the pediatric population.


Assuntos
Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico por imagem , Síndrome do Desconforto Respiratório do Recém-Nascido/patologia , Doença Aguda , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Radiografia , Estudos Retrospectivos
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