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1.
J Dairy Sci ; 104(7): 7415-7425, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33814147

RESUMO

Probiotics can ferment nondigestible carbohydrates and produce short-chain fatty acids (SCFA; acetate, propionate, and butyrate) in the human colon. In this study, the levels of SCFA were determined in the following yogurts fermented with different combinations of probiotics: (1) cocultures of Streptococcus thermophilus and Lactobacillus bulgaricus (control, C); (2) S. thermophilus, L. bulgaricus, and Bifidobacterium bifidum (C-Bb); (3) S. thermophilus, L. bulgaricus, and Lactobacillus acidophilus (C-La); and (4) S. thermophilus, L. bulgaricus, and Lactobacillus gasseri (C-Lg). Results showed that the acetate levels were significantly higher in C-Bb, C-La, and C-Lg yogurts than in C yogurt. Fermentation and physicochemical characteristics of all yogurts were identical. Treatment of mucus-secreting colon epithelial cells (HT29-MTX) with C-Bb, C-La, and C-Lg yogurt supernatants resulted in an increase in the expression of MUC2 and CDX2 and the production of mucin proteins. The adhesion of probiotics onto HT29-MTX cells increased following treatment with C-Bb, C-La, and C-Lg yogurt supernatants. Our data suggest that a yogurt diet rich in acetate improves the protective function of the intestinal epithelium.


Assuntos
Probióticos , Iogurte , Animais , Colo , Células Epiteliais , Ácidos Graxos Voláteis , Fermentação , Humanos , Mucinas , Streptococcus thermophilus
2.
Sci Total Environ ; 761: 143225, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33160667

RESUMO

Ambient fine particulate matter (PM2.5) data of similar continuously monitored species at two air monitoring sites with different characteristics within the City of Toronto were used to gauge the intra-city variations in the PM composition over a largely concurrent period spanning two years. One location was <8 m from the side of a major highway while the other was an urban background location. For the first time, multi-time resolution factor analysis was applied to dispersion-normalized concentrations to identify and quantify source contributions while reducing the influence of local meteorology. These factors were particulate sulphate (pSO4), particulate nitrate (pNO3), secondary organic aerosols (SOA), crustal matter (CrM) that were common to both sites, a hydrocarbon-like organic matter (HOM) exclusive to the urban background site, three black carbon related factors (BC, BC-HOM at the highway site, and a brown carbon rich factor (BC-BrC) at the urban background site), biomass burning organic matter (BBOM) and brake dust (BD) factors exclusive to the highway site. The PM2.5 composition was different between these two locations, over only a 10 km distance. The sum of SOA, pSO4 and pNO3 at the urban background site averaged 57% of the PM2.5 mass while the same species represented 43% of the average PM2.5 mass at the highway site. Local or site-specific factors may be of greater interest for control policy design. Thus, regression analyses with potential explanatory, site-specific variables were performed for results from the highway site. Three model approaches were explored: multiple linear regression (MLR), regression with a generalized reduced gradient (GRG) algorithm, and a generalized additive model (GAM). GAM gave the largest fraction of variance for the locally-found factors at the highway site. Heavy-duty vehicles were most important for explaining the black carbon (BC and BC-HOM) factors. Light-duty vehicles were dominant for the brake dust (BD) factor. The auxiliary modelling for the local factors showed that the traffic-related factors likely originated along the main roadways at their respective sites while the more regional factors, - pSO4, pNO3, SOA, - had sources that were both regional and local in origin and with contributions that varied seasonally. These results will be useful in understanding ambient particulate matter sources on a city scale that will support air quality management planning.

3.
J Dairy Sci ; 103(8): 7416-7424, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32475678

RESUMO

The objective of this study was to evaluate the antibacterial activities of extract derived from moringa leaves. In particular, the effect of moringa extract (Mor) on adhesion and invasion of Escherichia coli O55, Enterococcus faecalis, Staphylococcus simulans, and Serratia liquefaciens was evaluated in bovine mammary epithelial cells (MAC-T). Broth microdilution method, minimum inhibitory concentration and minimum bactericidal concentration assays, adhesion and invasion assays, and real-time PCR were performed. The minimum inhibitory concentration and minimum bactericidal concentration of Mor ranged from 12.5 to 50 mg/mL on 18 out of 27 tested isolates. Treatment of E. coli O55 with Mor (100 and 200 µg/mL) inhibited the adhesion and invasion on MAC-T cells via downregulation of adhesion factors (i.e., papC, f17c-A, and eaeA). Also, when MAC-T cells were pretreated with Mor (200 µg/mL, 12 h) and incubated with E. coli O55, Enterococcus faecalis, Staphylococcus simulans, or Serratia liquefaciens, both E. coli O55 and Enterococcus faecalis showed a significant decrease in adhesion and invasion. Staphylococcus simulans exhibited decreased adhesion and increased invasion. Serratia liquefaciens showed increased adhesion and decreased invasion. In addition, Mor increased mRNA expression of antioxidant enzymes (e.g., heme oxygenase-1, NAD(P)H:quinone oxidoreductase-1, and thioredoxin reductase 1) in MAC-T cells. In conclusion, 12.5 to 50 mg/mL of Mor exhibited antibacterial activity against 18 out of 27 tested isolates. Also, pretreatment of 200 µg/mL of Mor to MAC-T cells modulated adhesion and invasion of E. coli O55 and other mastitis-associated pathogens. Furthermore, Mor increased antioxidant capacities in MAC-T cells, but further in vivo studies are needed.


Assuntos
Antibacterianos/isolamento & purificação , Aderência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Glândulas Mamárias Animais/microbiologia , Moringa/química , Extratos Vegetais/farmacologia , Animais , Antibacterianos/farmacologia , Bovinos , Enterococcus faecalis , Células Epiteliais/microbiologia , Infecções por Escherichia coli/veterinária , Feminino , Mastite Bovina/microbiologia
4.
Climacteric ; 23(2): 173-177, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31538495

RESUMO

Background: The possibility of an association between early menopause and the risk of non-alcoholic fatty liver disease (NAFLD) is as yet unclear.Methods: The subjects consisted of 4354 postmenopausal women who participated in the 2010-2012 Korea National Health and Nutrition Examination Survey. Early, normal, and late menopause were defined as age at menopause <45 years, 45-54 years, and ≥55 years, respectively. NAFLD was defined by a hepatic steatosis index of >36.Results: When compared with normal menopausal women, early or late menopausal women had no significant differences in the odds ratios (ORs) of NAFLD: OR = 1.05, 95% confidence interval (CI), 0.83-1.32 and OR = 1.02, 95% CI, 0.75-1.39, respectively. These results remained similar after adjustment for known risk factors for NAFLD, reproductive factors, and comorbidities. The OR for NAFLD per 1-year increase in age at menopause was 1.01 (95% CI, 0.99-1.03; p = 0.329). The prevalence of advanced fibrosis was 2.1% (95% CI, 0.7-6.4%), 2.2% (95% CI, 1.3-3.8%), and 3.9% (95% CI, 1.2-12.2%) in early, normal, and late menopausal women, respectively.Conclusions: This study provides no evidence for an association of early menopause with NAFLD risk. However, NAFLD-related advanced fibrosis is highly prevalent in postmenopausal women.


Assuntos
Menopausa Precoce , Hepatopatia Gordurosa não Alcoólica/etiologia , Pós-Menopausa , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Prevalência , República da Coreia/epidemiologia
6.
Free Radic Res ; 48(11): 1311-21, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25096910

RESUMO

Prostaglandin E2 (PGE2) has been reported to play critical roles in cell fate decision by interacting with four types of prostanoid receptors such as EP1, EP2, EP3 and EP4. The present study was aimed at investigating the effect of the EP4-specific agonist CAY10598 in human colon cancer HCT116 cells. Our study revealed that treatment with CAY10598 significantly reduced the cell viability and induced apoptosis in HCT116 cells, as evidenced by the induction of p53 and Bax, release of cytochrome c, cleavage of caspase-9, -7, and -3, and PARP, and the inhibition of Bcl-2, Bcl-xL and survivin expression. Moreover, treatment with CAY10598 diminished the phosphorylation of JAK2, leading to the attenuation of STAT3 activation in HCT116 cells. CAY10598-induced apoptosis in cells which were transiently transfected with EP4 siRNA or treated with an EP4 antagonist prior to incubation with the compound remained unaffected, suggesting an EP4-independent mechanism of apoptosis induction by CAY10598. We found that treatment with CAY10598 generated reactive oxygen species (ROS) and pretreatment of cells with N-acetyl cysteine rescued cells from apoptosis by abrogating the inhibitory effect of CAY10598 on the activation of JAK2/STAT3 signaling. In conclusion, CAY10598 induced apoptosis in HCT116 cells in an EP4-independent manner, but through the generation of ROS and inactivation of JAK2/STAT3 signaling.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias do Colo/patologia , Dinoprostona/análogos & derivados , Pirrolidinonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Receptores de Prostaglandina E Subtipo EP4/agonistas , Fator de Transcrição STAT3/antagonistas & inibidores , Tetrazóis/farmacologia , Western Blotting , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Dinoprostona/genética , Dinoprostona/metabolismo , Dinoprostona/farmacologia , Humanos , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
7.
Anaesthesia ; 68(10): 1033-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23889075

RESUMO

The aim of this study was to predict the optimal depth for insertion of a left-sided central venous catheter in children. Using 3D chest computed tomography angiography, we measured the distance from a point where the internal jugular vein is at the superior border of the clavicle, and from a point where the subclavian vein is inferior to the anterior border of the clavicle, to the junction of the superior vena cava and the right atrium in 257 children. Linear regression analysis revealed that the distances correlated with age, weight and height. Simple formulae for the depth of a central venous catheter via the left internal jugular vein (0.07 × height (cm)) and the left subclavian vein (0.08 × height (cm)) were developed to predict placement of the central venous catheter tip at the junction of the superior vena cava with the right atrium. Using these fomulae, the proportion of catheter tips predicted to be correctly located was 98.5% (95% CI 96.8-100%) and 94.0% (95% CI 90.8-97.3%), respectively.


Assuntos
Cateterismo Venoso Central/métodos , Catéteres , Angiografia , Estatura , Criança , Pré-Escolar , Feminino , Humanos , Imageamento Tridimensional , Lactente , Veias Jugulares/anatomia & histologia , Veias Jugulares/diagnóstico por imagem , Masculino , Valor Preditivo dos Testes , Análise de Regressão , Estudos Retrospectivos , Veia Subclávia/anatomia & histologia , Veia Subclávia/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Veia Cava Superior/anatomia & histologia , Veia Cava Superior/diagnóstico por imagem
8.
Inhal Toxicol ; 16 Suppl 1: 31-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15204791

RESUMO

On-road experiments were conducted to determine the sensitivities of rats to real-world aerosol. This article summarizes the on-road aerosol and gas measurements and provides background information for the companion paper on the rat exposures. Measurements were carried out over 10 days, 6 h/day, driving a route from Rochester to Buffalo. Aerosol instrumentation used in this study included two scanning mobility particle sizers (SMPS) to determine the aerosol size distribution from 10 to 300 nm, 2 stand-alone condensation particle counters to determine the total aerosol number concentration, and an electrical aerosol detector to determine the aerosol length concentration. A thermal denuder (TD) was used with one of the SMPS instruments to determine the size distribution of the non-volatile fraction. Filter samples were collected and analyzed for elemental carbon, and gas analyzers measured ambient levels of CO, CO(2), and NO. Average daily total aerosol number concentration ranged from 200,000 to 560,000 particles/cm(3). Past studies on urban highways have measured total number concentrations ranging between 10(4) and 10(6) particles/cm(3). The average daily NO concentration ranged from 0.10 to 0.24 ppm and the corresponding CO(2) concentration ranged from 400 to 420 ppm. The average daily geometric number mean particle size determined by the SMPS ranged from 15 to 20 nm. The TD reduced the average SMPS number concentration between 87 and 95% and the SMPS volume between 54 and 83%, suggesting that most of the particles consisted of volatile material. The TD also increased the geometric number mean diameter from 15 to 20 nm to 30 to 40 nm.


Assuntos
Poluentes Atmosféricos/análise , Condução de Veículo , Gases/análise , Exposição por Inalação/análise , Testes de Toxicidade/instrumentação , Aerossóis , Poluentes Atmosféricos/toxicidade , Desenho de Equipamento , Veículos Automotores , New York , Tamanho da Partícula , Testes de Toxicidade/métodos , Tempo (Meteorologia)
9.
Chemosphere ; 55(5): 781-5, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15013684

RESUMO

The behavior and fate of nonionic hydrophobic organic compounds (HOCs) in the environment are mainly controlled by their interactions with various components of soils and sediments. Due to their large surface area and abundance in many soils, smectites may greatly influence the fate and transport of the contaminants in the environment. In our experiments, HOC sorption by hexadecyltrimethylammonium (HDTMA)-modified smectite linearly increased with the amount of HDTMA added to the clay. However, tetramethylammonium (TMA)- and dodecyltrimethylammonium (DTMA)-modified smectites showed not only inferiority in their sorption of HOC compared with the HDTMA-smectite, but also a partially decreased HOC sorption at specific surfactant loading levels. This means that the sorption of organoclays for organic contaminants was significantly influenced by the amount and size of the surfactants added on the clay. In addition, it seems that the interlayer structure (e.g., pore size) formed at each surfactant loading level plays an important role to adsorb HOC in different amount.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Compostos Orgânicos/química , Silicatos/química , Adsorção , Cinética , Porosidade , Compostos de Amônio Quaternário/química , Solo/análise , Tensoativos/química , Difração de Raios X
11.
Artigo em Inglês | MEDLINE | ID: mdl-11501307

RESUMO

Adsorption characteristics of the nuclides onto kaolinite were investigated by batch experiment under various pH conditions and concentrations of groundwater cations (Ca2+, Mg2+, K+ and Na+) and anions (HCO3-, CO3(2-) and SO4(2-). Adsorption removal of 137Cs and 90Sr by kaolinite greatly increased as the concentration of groundwater cations increased from 10(-5) to 10(-1) M. In contrast, the pH exerted a small effect on the adsorption of 137Cs and 90Sr onto kaolinite. The zeta potential of kaolinite particles showed a negative increase of amphoteric surface charge with increasing pH. The adsorption behavior of 90Sr was also highly dependent on the concentration of bicarbonate. The thermodynamic saturation index indicated that bicarbonate exerts great effect on strontium adsorption by the precipitation of a strontianite (SrCO3) and a change in pH.


Assuntos
Caulim/química , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise , Adsorção , Radioisótopos de Césio/química , Poluição Ambiental/prevenção & controle , Concentração de Íons de Hidrogênio , Radioisótopos de Estrôncio/química
12.
Dev Dyn ; 220(2): 175-86, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11169851

RESUMO

Hypoxia is a well-known signal for angiogenesis, but the recent proposal that hypoxia exists in developing embryonic tissues and that it induces vascular development remains to be proven. In the present study, we demonstrate the presence of hypoxia in normal developing embryos by means of a hypoxia marker, pimonidazole, and its associated antibody. Our data clearly show that hypoxia marker immunoreactivity was highly detected in developing neural tubes, heart, and intersomitic mesenchyme at an early stage of organogenesis, suggesting that hypoxia may exist in the early stages of embryo development. We also found that hypoxia inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) were spatiotemporally co-localized with possible hypoxic regions in embryos. Investigation of platelet endothelial cell adhesion molecule (PECAM) expression provides evidence that endothelial cells proliferate and form the vessels in the hypoxic region in developing organs. Furthermore, we found that hypoxia induced both HIF-1alpha and VEGF in F9 embryonic stem and differentiated cells. Thus, we suggest that hypoxia may exist widely in developing embryonic tissues and that it may act as a signal for embryonic blood vessel formation in vivo.


Assuntos
Vasos Sanguíneos/embriologia , Encéfalo/embriologia , Proteínas de Ligação a DNA/genética , Desenvolvimento Embrionário e Fetal/fisiologia , Fatores de Crescimento Endotelial/genética , Endotélio Vascular/embriologia , Hipóxia , Linfocinas/genética , Proteínas Nucleares/genética , Fatores de Transcrição , Animais , Anticorpos Monoclonais , Biomarcadores , Vasos Sanguíneos/citologia , Encéfalo/citologia , Bucladesina/farmacologia , Diferenciação Celular , Hipóxia Celular/fisiologia , Proteínas de Ligação a DNA/análise , Fatores de Crescimento Endotelial/análise , Endotélio Vascular/citologia , Regulação da Expressão Gênica no Desenvolvimento , Fator 1 Induzível por Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia , Imuno-Histoquímica , Linfocinas/análise , Camundongos , Camundongos Endogâmicos BALB C , Nitroimidazóis/análise , Nitroimidazóis/imunologia , Proteínas Nucleares/análise , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/fisiologia , Teratoma , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
13.
Acta Otolaryngol ; 115(5): 664-71, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8928640

RESUMO

The aim of this study was to evaluate histologic changes after long-term administration of the topical nasal decongestants phenylephrine and oxymetazoline. Ninety healthy rabbits were divided into 3 groups for topical administration for 1 week, 2 weeks, and 4 weeks. Each group was subdivided into 3 subgroups by topical administration of phenylephrine. oxymetazoline, and physiologic saline as controls. Each study group thus consisted of 10 rabbits. Phenylephrine was administered by 2 puffs in the left nostril 5 times daily and oxymetazoline by 2 puffs twice a day using metered sprayers giving 0.10 ml in each puff with a dosage used in clinical practice. For statistical significance the Kolmogorov-Smirnov test was used. Light and electron microscopic examination were performed after obtaining nasal respiratory mucosa from the nasal septum of the rabbits. Administration of phenylephrine and oxymetazoline for more than 2 weeks caused histologic changes including ciliary loss, epithelial ulceration, inflammatory cell infiltration and subepithelial edema, and the changes were more pronounced with increasing administration duration of the decongestants. Ciliary loss was prominent in the 4-week phenylephrine and oxymetazoline groups. There were significantly severer changes in the morphologic variables in the decongestant groups compared with the control group according to administration duration (p < 0.05). Dilatation or vacuolization of mitochondria and endoplasmic reticula and vesicles ill the cytoplasm were observed in the 2- and 4-week phenylephrine groups as well as the 2- and 4-week oxymetazoline groups. Mild widening of the intercellular space was observed in the 4-week phenylephrine group. Purulent maxillary sinusitis developed in 6 of 10 rabbits treated for 4 weeks with phenylephrine. The results of this study suggest that the administration of decongestants may cause ciliary loss with subsequent inflammatory changes in the nasal respiratory mucosa.


Assuntos
Descongestionantes Nasais/farmacologia , Mucosa Nasal/efeitos dos fármacos , Oximetazolina/farmacologia , Fenilefrina/farmacologia , Administração Tópica , Aerossóis , Animais , Cílios/efeitos dos fármacos , Cílios/patologia , Retículo Endoplasmático/diagnóstico por imagem , Retículo Endoplasmático/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/patologia , Mitocôndrias/diagnóstico por imagem , Mitocôndrias/efeitos dos fármacos , Descongestionantes Nasais/administração & dosagem , Mucosa Nasal/diagnóstico por imagem , Mucosa Nasal/patologia , Oximetazolina/administração & dosagem , Fenilefrina/administração & dosagem , Coelhos , Ultrassonografia
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