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1.
Artigo em Inglês | MEDLINE | ID: mdl-32850771

RESUMO

The waste produced by petrochemical industries has a significant environmental impact. Biotechnological approaches offer promising alternatives for waste treatment in a sustainable and environment-friendly manner. Microbial consortia potentially clean up the wastes through degradation of hydrocarbons using biosurfactants as adjuvants. In this work, microbial consortia were obtained from a production water (PW) sample from a Brazilian oil reservoir using enrichment and selection approaches in the presence of oil as carbon source. A consortium was obtained using Bushnell-Haas (BH) mineral medium with petroleum. In parallel, another consortium was obtained in yeast extract peptone dextrose (YPD)-rich medium and was subsequently compared to the BH mineral medium with petroleum. Metagenomic sequencing of these microbial communities showed that the BH consortium was less diverse and predominantly composed of Brevibacillus genus members, while the YPD consortium was taxonomically more diverse. Functional annotation revealed that the BH consortium was enriched with genes involved in biosurfactant synthesis, while the YPD consortium presented higher abundance of hydrocarbon degradation genes. The comparison of these two consortia against consortia available in public databases confirmed the enrichment of biosurfactant genes in the BH consortium. Functional assays showed that the BH consortium exhibits high cellular hydrophobicity and formation of stable emulsions, suggesting that oil uptake by microorganisms might be favored by biosurfactants. In contrast, the YPD consortium was more efficient than the BH consortium in reducing interfacial tension. Despite the genetic differences between the consortia, analysis by a gas chromatography-flame ionization detector showed few significant differences regarding the hydrocarbon degradation rates. Specifically, the YPD consortium presented higher degradation rates of C12 to C14 alkanes, while the BH consortium showed a significant increase in the degradation of some polycyclic aromatic hydrocarbons (PAHs). These data suggest that the enrichment of biosurfactant genes in the BH consortium could promote efficient hydrocarbon degradation, despite its lower taxonomical diversity compared to the consortium enriched in YPD medium. Together, these results showed that cultivation in a minimal medium supplemented with oil was an efficient strategy in selecting biosurfactant-producing microorganisms and highlighted the biotechnological potential of these bacterial consortia in waste treatment and bioremediation of impacted areas.

2.
J Dent Res ; 97(9): 1017-1022, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29578824

RESUMO

The aim of this study was to investigate hydrogen mobility within innate and demineralized human dentine. Dentine sections from extracted human molars, demineralized or not, were analyzed by combining neutron spectroscopy with thermal analysis. For the thermal analysis of the samples, differential scanning calorimetry and thermal gravimetric analysis, coupled with Fourier transform infrared spectroscopy, were performed. The hydrogen dynamics of water, collagen, and hydroxyl groups present in the samples were investigated via neutron spectroscopy. From the mass loss observed from the thermogravimetric analysis curves up to 600 °C, the same amount of organic content is identified in the samples. From the differential scanning calorimetry curves, a higher change in enthalpy associated with the denaturation of collagen is registered in the demineralized dentine; that is, a structural change occurs in the collagen subsequent to demineralization. Since the intensity measured by neutron spectroscopy is dominated by the signal from hydrogen, in our samples-coming mostly from the bulk-like and loosely bound water as well as from the collagen itself-higher proton mobility within the demineralized dentine was detected when compared with innate dentine. In the demineralized dentine, this proton mobility amounts to 80%, while the remaining hydrogen accounts for a combination of 1) structural hydroxyls, as a result of the incomplete dissolution of the mineral phase by acid etching, and 2) hydrogen tightly bound in the collagen structure. By combining neutron spectroscopy with the calorimetry data, our findings support the idea that hydroxyapatite protects the collagen in innate dentine. Demineralized dentine, however, acts as a sponge where free bulk-like water is trapped.


Assuntos
Dentina/metabolismo , Água/metabolismo , Varredura Diferencial de Calorimetria , Colágeno/metabolismo , Humanos , Técnicas In Vitro , Dente Molar , Nêutrons , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral , Desmineralização do Dente
3.
Artigo em Português | LILACS | ID: lil-621577

RESUMO

A regulação do metabolismo lipídico com drogas ou alimentos naturais é um alvo importante para diminuir o risco de doenças cardiovasculares. O objetivo deste estudo foi verificar o efeito da lecitina de soja na dislipidemia e na hipertrofia ventricular de camundongos hipercolesterolêmicos. Utilizaram-se quatro grupos de camundongos LDLr-/- com 3 meses de idade que receberam a seguintes dietas: Grupo S- ração padrão; Grupo S+Lec- ração padrão e lecitina de soja; Grupo HL- ração hiperlipídica; e Grupo HL+Lec- ração hiperlipídica e lecitina de soja. Após 15 dias, o sangue foi coletado para análise sérica dos lipídeos e da proteína C reativa. O ventrículo esquerdo foi separado, a proporção peso ventricular (mg) pelo peso do animal (g) foi calculada e, em seguida, processado histologicamente. Cortes histológicos foram corados com hematoxilina/eosina e picrosírius red para avaliar alterações morfológicas e morfométricas ventriculares. A lecitina de soja apresentou efeito antidislipidêmico e aumentou os níveis séricos de HDL nos camundongos do grupo S+Lec. Entretanto, nos camundongos do grupo HL+lec, a lecitina de soja não preveniu a dislipidemia, apenas aumentou o nível sérico do HDL. Este efeito nestes animais influenciou no processo inflamatório cardiovascular, reduzindo o nível sérico de proteína C reativa; e prevenindo a hipertrofia ventricular esquerda. A utilização da lecitina de soja representa um tratamento e/ou uma prevenção alternativa de baixo custo para as dislipidemias não associadas com dieta hiperlipídica. Contudo, a lecitina de soja aumenta os níveis séricos do HDL prevenindo o desenvolvimento da HVE mesmo em dislipidemias associadas com dieta hiperlipídica.


The regulation of lipid metabolism with drugs or natural foods is an important target for reducing the risk of cardiovascular disease. The aim of this study was to investigate the effects of soy lecithin on left ventricular hypertrophy (LVH) and dyslipidemia in hypercholesterolemic mice. We used four experimental groups of LDLr-/- mice (aged 3 months), which received the following diets: Group S: standard diet, Group S+Lec: standard diet and soy lecithin; Group HL: hyperlipidic diet and Group HL+Lec: hyperlipidic diet and soy lecithin. After 15 days on these diets, blood was collected for analysis of serum lipids and C-reactive protein. The left ventricle was dissected out and weighed and the ratio of its weight to the body weight of the animal was calculated, after which it was processed histologically. Sections were stained with hematoxylin-eosin and picrosirius red, to assess morphological and morphometric changes in the ventricle. In Group S+Lec, the soy lecithin had an antidyslipidemic effect and enhanced the serum levels of HDL. However, in the mice in group HL+Lec, soy lecithin did not prevent dyslipidemia, only increasing the serum level of HDL. These effects in these animals influenced the cardiovascular inflammatory process, reducing the level of serum C-reactive protein and preventing LVH. Soy lecithin could thus be used as a treatment or a low-cost alternative preventative measure against dyslipidemia associated with a non-fat diet. However, soy lecithin increases the serum level of HDL, reducing the risk of LVH even in dyslipidemia associated with a high-fat diet.


Assuntos
Animais , Ratos , Dislipidemias , Hipertrofia Ventricular Esquerda , Lecitinas/uso terapêutico , Camundongos
4.
Artigo em Português | LILACS | ID: lil-604993

RESUMO

Neste estudo experimental investigou-se a influência da dislipidemia nos parâmetros do hemograma. Coletaram-se amostras de sangue de camundongos wild type, alimentados com dieta padrão, e de camundongos knockout para o gene do receptor de lipoproteína de baixa densidade, alimentados com dietas padrão e hiperlipídica. Determinaram-se os parâmetros do hemograma associando-os com os níveis plasmáticos de lipídeos. Os resultados mostraram uma associação negativa entre os níveis plasmáticos de lipoproteína de alta densidade e as contagens total e diferencial de leucócitos e plaquetas nos camundongos knockout para o gene do receptor de lipoproteína de baixa densidade. Essa relação demonstrou importante influência da lipoproteína de alta densidade na modulação da resposta imunológica e inflamatória na dislipidemia. Portanto, a avaliação dos resultados do hemograma correlacionada com os níveis plasmáticos de lipídeos, rotineiramente, pode ser promissora na prevenção e no prognóstico da severidade de quadros patológicos que envolvam respostas imunológicas nas dislipidemias.


The aim of this study was to investigate the influence of dyslipidemia on the hemogram. Blood samples were collected from wild type mice fed a standard diet and from knockout mice for the low density lipoprotein (LDL) receptor gene fed on high-fat and standard diets. The blood cell counts were analyzed for their association with plasma lipid levels. The results showed a negative association between high density lipoprotein (HDL) plasma levels and complete and differential leukocyte and platelet counts in knockout mice for the LDL receptor gene. This relation revealed the important influence of the HDL on the modulation of the immune and inflammatory response in dyslipidemia. Therefore, routine analysis of the hemogram, correlated with the plasma lipid levels, may be valuable in the prevention and prognosis of the severity of pathological processes involving immune responses in dyslipidemia.


Assuntos
Animais , Masculino , Camundongos , Contagem de Células Sanguíneas , Dislipidemias/complicações , Lipoproteínas HDL/sangue , Volume Plasmático , Contagem de Leucócitos , Camundongos
5.
Rev. bras. plantas med ; 11(2): 184-189, 2009. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-614844

RESUMO

Cochlospermum regium é uma planta de áreas de cerrado, caatinga e pantanal. Na medicina popular é conhecida por "algodão-do-campo" e suas raízes são utilizadas para o tratamento de infecções uterinas, intestinais, gastrite, úlceras e artrite. Atualmente, o extrativismo e a destruição dos habitats naturais colocaram o algodão-do-campo na lista de espécies medicinais nativas prioritárias para conservação ex situ. O objetivo deste trabalho foi desenvolver uma metodologia para a conservação in vitro do algodão-do-campo e fornecer subsídios para estudos de micropropagação da espécie. Sementes de algodão-do-campo foram testadas quanto à germinação in vitro pela escarificação ou não das sementes em ácido sulfúrico e inoculação em meio de cultura MS. Para a conservação in vitro, segmentos nodais retirados das plântulas germinadas in vitro foram avaliados por 90 dias sob três regimes de temperatura (10, 20, e 25ºC) e em três concentrações de meio WPM (½, ¾ e pleno). Verificou-se que sementes escarificadas apresentaram percentual de germinação in vitro de 93,3 por cento aos 30 dias, valor significativamente superior aos 13,3 por cento observados nas sementes não escarificadas. A conservação da espécie in vitro mostrou-se viável, desde que as culturas sejam mantidas em câmara de crescimento a 20ºC em meio de cultivo ½WPM. Sob estas condições os explantes mantiveram um crescimento mínimo e percentual de sobrevivência de 100 por cento, após três meses de avaliação.


Cochlospermum regium is a plant from cerrado, caatinga and pantanal areas. In popular medicine, it is known as "algodão-do-campo" and its roots are used to treat uterine and intestinal infections, gastritis, ulcers and arthritis. Nowadays, extraction activities and the destruction of natural habitats has made "algodão-do-campo" one of the major native medicinal species for ex situ conservation. The aim of this work was to develop a methodology for the in vitro conservation of "algodão-do-campo", contributing to studies on the micropropagation of this species. In vitro germination was evaluated in "algodão-do-campo" seeds subjected to scarification or not with sulfuric acid and inoculation in MS medium. For in vitro conservation, nodal segments from in vitro-germinated seedlings were evaluated for 90 days at three temperatures (10, 20 and 25ºC) and three WPM medium concentrations (½, ¾ and full-strength). Scarified seeds presented 93.3 percent in vitro germination at 30 days of cultivation, a significantly higher value than the 13.3 percent observed for non-scarified seeds. The in vitro conservation of "algodão-do-campo" showed to be viable once cultures are kept in a growth chamber at 20ºC in ½ WPM medium. Under such conditions, the explants presented a minimal growth and 100 percent survival after three evaluation months.


Assuntos
Técnicas In Vitro/métodos , Bixaceae/classificação , Plantas Medicinais/classificação , Germinação
6.
Braz J Med Biol Res ; 38(5): 767-75, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15917959

RESUMO

The aim of the present study was to evaluate the prevalence of HEV, TTV and GBV-C/GBV-C/HGV in patients with acute viral hepatitis A, B and non-A-C. We evaluated sera of 94 patients from a sentinel program who had acute hepatitis A (N = 40), B (N = 42) and non-A-C (N = 12); 71 blood donors served as controls. IgM and anti-HEV IgG antibodies were detected by enzyme immunoassay using commercial kits. TTV and GBV-C/HGV were detected by nested PCR; genotyping was done by sequencing and phylogenetic analysis. Anti-HEV IgG was present in 38, 10 and 17% of patients with hepatitis A, B and non-A-C. Four patients with hepatitis A and 1 with non-A-C hepatitis also had anti-HEV IgM detected in serum. TTV was detected in 21% of patients with acute hepatitis and in 31% of donors. GBV-C/HGV was detected in 9% of patients with hepatitis, and in 10% of donors. We found TTV isolates of genotypes 1, 2, 3, and 4 and GBV-C/HGV isolates of genotypes 1 and 2. Mean aminotransferase levels were lower in patients who were TTV or GBV-C/HGV positive. In conclusion, the detection of anti-HEV IgM in some acute hepatitis A cases suggests co-infection with HEV and hepatitis E could be the etiology of a few cases of sporadic non-A-C hepatitis in Salvador, Brazil. TTV genotype 1, 2, 3 and 4 isolates and GBV-C/HGV genotype 1 and 2 strains are frequent in the studied population. TTV and GBV-C/HGV infection does not appear to have a role in the etiology of acute hepatitis.


Assuntos
Vírus GB C/imunologia , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Hepatite Viral Humana/virologia , Torque teno virus/imunologia , Doença Aguda , Biomarcadores , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Vírus GB C/genética , Genótipo , Vírus da Hepatite E/genética , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/epidemiologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Reação em Cadeia da Polimerase , Prevalência , Vigilância de Evento Sentinela , Índice de Gravidade de Doença , Torque teno virus/genética
7.
Braz. j. med. biol. res ; 38(5): 767-775, May 2005. ilus, tab
Artigo em Inglês | LILACS | ID: lil-400949

RESUMO

The aim of the present study was to evaluate the prevalence of HEV, TTV and GBV-C/GBV-C/HGV in patients with acute viral hepatitis A, B and non-A-C. We evaluated sera of 94 patients from a sentinel program who had acute hepatitis A (N = 40), B (N = 42) and non-A-C (N = 12); 71 blood donors served as controls. IgM and anti-HEV IgG antibodies were detected by enzyme immunoassay using commercial kits. TTV and GBV-C/HGV were detected by nested PCR; genotyping was done by sequencing and phylogenetic analysis. Anti-HEV IgG was present in 38, 10 and 17 percent of patients with hepatitis A, B and non-A-C. Four patients with hepatitis A and 1 with non-A-C hepatitis also had anti-HEV IgM detected in serum. TTV was detected in 21 percent of patients with acute hepatitis and in 31 percent of donors. GBV-C/HGV was detected in 9 percent of patients with hepatitis, and in 10 percent of donors. We found TTV isolates of genotypes 1, 2, 3, and 4 and GBV-C/HGV isolates of genotypes 1 and 2. Mean aminotransferase levels were lower in patients who were TTV or GBV-C/HGV positive. In conclusion, the detection of anti-HEV IgM in some acute hepatitis A cases suggests co-infection with HEV and hepatitis E could be the etiology of a few cases of sporadic non-A-C hepatitis in Salvador, Brazil. TTV genotype 1, 2, 3 and 4 isolates and GBV-C/HGV genotype 1 and 2 strains are frequent in the studied population. TTV and GBV-C/HGV infection does not appear to have a role in the etiology of acute hepatitis.


Assuntos
Humanos , Masculino , Feminino , Vírus GB C/imunologia , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Hepatite Viral Humana/virologia , Torque teno virus/imunologia , Doença Aguda , Biomarcadores , Brasil/epidemiologia , Estudos de Casos e Controles , Vírus GB C/genética , Genótipo , Vírus da Hepatite E/genética , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/epidemiologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Reação em Cadeia da Polimerase , Prevalência , Vigilância de Evento Sentinela , Índice de Gravidade de Doença , Torque teno virus/genética
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