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1.
J Biol Regul Homeost Agents ; 26(2): 253-64, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22824753

RESUMO

Adipogenesis is a continuous process even in adult adipose tissue for the presence of preadipocytes that, when subjected to appropriate stimuli can proliferate and differentiate. ChREBP, the essential transcription factor for lipogenesis, is expressed in all tissues, but mainly in lipogenic organs. In this study, we focused on ChREBP expression during preadipocytes differentiation. Since it was found that cyanidin-3 reduces body weight in mice even in the presence of a high-fat diet, by decreasing levels of blood glucose and by improving insulin sensitivity, we studied the effect of this substance on adipogenic differentiation. For this purpose we used preadipocytes obtained from subcutaneous and visceral human adipose explant tissue, characterized and stimulated to differentiate in selective media. On cytofluorimetric analysis these cells showed mesenchymal markers (CD29, CD90, CD44), whereas they were negative for hematopoietic markers (CD45, CD10, CD117,CD31). ChREBP expression levels were quantified by immunoelectron-microscopy and western blotting analysis. In this report we show that ChREBP is expressed in preadipocytes (both nuclear and cytoplasmic compartments); the cytoplasmic level of ChREBP increased by 50 percent on day seven of differentiation into mature adipocytes. Cyanidin reduced differentiation by 20 percent (as evaluated by red oil O staining) and the expression of ChREBP. In addition, cyanidin-treated cells showed abnormal morphology, a square shape with irregular size, probably due to the fact that cyanidin may interfere with the extracellular matrix. These findings suggest that dietary cyanidin, may have inhibitory effects on adipogenesis.


Assuntos
Adipogenia/efeitos dos fármacos , Antocianinas/farmacologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/análise , Adipócitos/química , Adipócitos/citologia , Diferenciação Celular/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Células-Tronco/química , Células-Tronco/citologia
2.
Biosens Bioelectron ; 26(3): 983-90, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20833014

RESUMO

Microbial screening is a primary concern for many products. Traditional techniques based on standard plate count (SPC) are accurate, but time consuming. Furthermore, they require a laboratory environment and qualified personnel. The impedance technique (IT) looking for changes in the electrical characteristics of the sample under test (SUT) induced by bacterial metabolism represents an interesting alternative to SPC since it is faster (3-12h vs. 24-72 h for SPC) and can be easily implemented in automatic form. With this approach, the essential parameter is the time for bacteria concentration to reach a critical threshold value (about 10(7) cfu mL(-1)) capable of inducing significant variations in the SUT impedance, measured by applying a 100 mV peak-to-peak 200 Hz sinusoidal test signal at time intervals of 5 min. The results of this work show good correlation between data obtained with the SPC approach and with impedance measurements lasting only 3h, in the case of highly contaminated samples (10(6) cfu mL(-1)). Furthermore, this work introduces a portable system for impedance measurements composed of an incubation chamber containing the SUT, a thermoregulation board to control the target temperature and an impedance measurement board. The mix of cheap electronics and fast detection time provides a useful tool for microbial screening in industrial and commercial environments.


Assuntos
Carga Bacteriana/instrumentação , Técnicas Biossensoriais/instrumentação , Bioengenharia , Impedância Elétrica , Desenho de Equipamento , Temperatura
3.
J Appl Microbiol ; 105(5): 1266-76, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18778294

RESUMO

AIMS: To determine the antioxidative activity, glutathione production, acid and bile tolerance and carbohydrate preferences of Lactobacillus plantarum LP 1, Streptococcus thermophilus Z 57 and Bifidobacterium lactis B 933. METHODS AND RESULTS: The intact bacteria exhibited antioxidative capacity against linolenic acid and ascorbate oxidation. The antioxidative activity of cell-free extracts was determined by chemiluminescent assay and agreed with total glutathione content. Superoxide dismutase was negligible in all the strains. Bile and gastric juice resistance was tested in vitro to estimate the transit tolerance in the upper gastrointestinal tract. Bifidobacterium lactis B 933 and L. plantarum LP 1 were more acid tolerant than S. thermophilus Z 57. All the strains were resistant to bile. Among 13 indigestible carbohydrates, galacto-oligosaccharides and fructo-oligosaccharides were utilized by all the strains and did not affect survival in human gastric juice. CONCLUSIONS: These potential probiotic strains exhibited antioxidative properties and good viability in gastric juice and bile may indicate tolerance to the transit through the upper gastrointestinal tract. Galacto-oligosaccharides and fructo-oligosaccharides are the most appropriate prebiotics to be used in effective synbiotic formulations. SIGNIFICANCE AND IMPACT OF THE STUDY: These results outline promising strains with antioxidative properties. Carbohydrate preferences can be exploited in order to develop synbiotic products.


Assuntos
Antioxidantes , Bifidobacterium/crescimento & desenvolvimento , Metabolismo dos Carboidratos/fisiologia , Lactobacillus plantarum/crescimento & desenvolvimento , Streptococcus thermophilus/crescimento & desenvolvimento , Animais , Bifidobacterium/metabolismo , Meios de Cultura , Suco Gástrico/microbiologia , Glutationa/biossíntese , Humanos , Lactobacillus plantarum/metabolismo , Ácido Linoleico , Medições Luminescentes , Viabilidade Microbiana , Oxirredução , Polissacarídeos/metabolismo , Probióticos/metabolismo , Streptococcus thermophilus/metabolismo , Superóxido Dismutase/metabolismo , Suínos
4.
Biosens Bioelectron ; 23(11): 1616-23, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18353628

RESUMO

The detection of microbial concentration, essential for safe and high quality food products, is traditionally made with the plate count technique, that is reliable, but also slow and not easily realized in the automatic form, as required for direct use in industrial machines. To this purpose, the method based on impedance measurements represents an attractive alternative since it can produce results in about 10h, instead of the 24-48h needed by standard plate counts and can be easily realized in automatic form. In this paper such a method has been experimentally studied in the case of ice-cream products. In particular, all main ice-cream compositions of real interest have been considered and no nutrient media has been used to dilute the samples. A measurement set-up has been realized using benchtop instruments for impedance measurements on samples whose bacteria concentration was independently measured by means of standard plate counts. The obtained results clearly indicate that impedance measurement represents a feasible and reliable technique to detect total microbial concentration in ice-cream, suitable to be implemented as an embedded system for industrial machines.


Assuntos
Técnicas Biossensoriais/instrumentação , Contagem de Colônia Microbiana/instrumentação , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Sorvetes/análise , Sorvetes/microbiologia , Técnicas Biossensoriais/métodos , Contagem de Colônia Microbiana/métodos , Impedância Elétrica , Eletroquímica/instrumentação , Eletroquímica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Análise de Alimentos/métodos
5.
Clin Hemorheol Microcirc ; 35(1-2): 231-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16899934

RESUMO

To verify the potential involvement of the age-dependent modifications of EC-SOD activity in the impairment of plasma NO availability with advancing age, 40 healthy men divided into 4 age groups for the purpose of comparison (young: 27.4 +/- 1.5 years; middle: 50.8 +/- 2.2, years; old: 70.0 +/- 1.8 years; very old: 86.1 +/- 1.1 years) were enrolled in this study. Plasma samples were used for measurements of the stable end-product nitrite/nitrate (NOx), as an expression of NO availability, EC-SOD activity, thiobarbituric acid reactive substances (TBARS) as a marker of lipid peroxidation, low density lipoprotein (LDL) copper-mediated oxidation in vitro and total antioxidant capacity (TEAC). Our results indicated a significant age-related progressive decrease of plasma NOx content and EC-SOD activity and their values were positively correlated (r = 0.713, p < 0.001). Increased TBARS amount together with reduced lag time for in vitro oxidation of LDL and decreased content of TEAC were observed with advancing age. Finally, EC-SOD values were negatively correlated with plasma TBARS values (r = -0.855, p < 0.001). Findings of the present study suggest that the decrease of antioxidant defence strategies play a primary role by compromising NO availability in normally aged individuals, particularly through a progressive decrease of EC-SOD activity.


Assuntos
Envelhecimento/fisiologia , Peroxidação de Lipídeos/fisiologia , Óxido Nítrico/metabolismo , Superóxido Dismutase/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/análise , Superóxido Dismutase/metabolismo
6.
J Acoust Soc Am ; 107(2): 709-13, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10687679

RESUMO

A new approach to the acoustics of closed spaces is developed that involves solutions for polygonal shapes in explicit form. It is shown that exact solutions can be constructed for polygonal geometries where all the interior angles are equal to pi/n (n is an integer). It is stated that the set of such polygons consists of the rectangle (known result) and three types of triangles. Some new explicit formulas are obtained for the eigenfrequencies of the triangles. It is demonstrated that the proposed technique also permits an exact representation of the impulse response function for the geometries described.

7.
Eur J Nutr ; 39(6): 248-55, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11395984

RESUMO

BACKGROUND: Animal studies have demonstrated dramatic changes in the intestinal flora during total enteral (TEN) or parenteral (TPN) nutrition. AIM OF THE STUDY: To assess the impact of TEN and TPN on human intestinal microflora. METHODS: Eight patients on fiber-free TEN, five patients on TPN, and ten controls were studied. Fecal bacteria were identified and numbered (logCFU/g feces), and fecal short-chain fatty acids (SCFAs) were measured in stool samples, by gas-liquid chromatography. RESULTS: In TEN patients, compared to controls (P < 0.01), aerobes were increased (8.46 +/- 0.24) while anaerobes were decreased (5.79 +/- 0.84). In TPN patients, both aerobes and anaerobes were decreased compared to controls (5.64 +/- 0.27 and 5.31 +/- 1.09 respectively, P < 0.01). Total SCFAs were lower in TPN patients than in TEN patients (48.3 +/- 16.6 vs 118.6 +/- 24.1 mmol/kg, P < 0.05). CONCLUSIONS: Both TPN and TEN induce modifications in the intestinal microflora. During TPN, a homogeneous decrease occurs in both aerobic and anaerobic bacteria. TEN decreases only anaerobic bacteria, while aerobic bacteria are increased. This imbalance may play a role in the pathophysiology of TEN-induced diarrhea.


Assuntos
Bactérias Aeróbias/crescimento & desenvolvimento , Bactérias Anaeróbias/crescimento & desenvolvimento , Nutrição Enteral/efeitos adversos , Fezes/microbiologia , Mucosa Intestinal/microbiologia , Nutrição Parenteral Total/efeitos adversos , Cromatografia Gasosa , Contagem de Colônia Microbiana , Ácidos Graxos Voláteis/análise , Fezes/química , Feminino , Humanos , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade
8.
Appl Opt ; 38(6): 896-907, 1999 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-18305689

RESUMO

The problems encountered in the elaboration of measurements of direct and sky diffuse solar irradiance are the following: (1) to carry out the calibration for the direct irradiance, which consists in determining the direct irradiance at the upper limit of the atmosphere; (2) to carry out the calibration for the diffuse irradiance, which consists in determining the solid viewing angle of the sky radiometer; (3) to determine the input parameters, namely, ground albedo, real and imaginary parts of the aerosol refractive index, and aerosol radius range; and (4) to determine from the optical data the columnar aerosol optical depth and volume radius distribution. With experimental data and numerical simulations a procedure is shown that enables one to carry out the two calibrations needed for the sky radiometer, to determine a best estimate of the input parameters, and, finally, to obtain the average features of the atmospheric aerosols. An interesting finding is that inversion of only data of diffuse irradiance yields the same accuracy of result as data of both diffuse and direct irradiance; in this case, only calibration of the solid viewing angle of the sky radiometer is needed, thus shortening the elaboration procedure. Measurements were carried out in the Western Mediterranean Sea (Italy), in Tokyo (Japan), and in Ushuaia (Tierra del Fuego, Argentina); data were elaborated with a new software package, the Skyrad code, based on an efficient radiative transfer scheme.

9.
Acta Obstet Gynecol Scand ; 77(7): 707-11, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9740516

RESUMO

BACKGROUND: The aim of our study was to evaluate the hemodynamic response to acute maternal hyperoxygenation (O2 test) in a group of growth retarded fetuses with absence or reversal of end-diastolic velocity (AREDV) in the umbilical artery (UA) and to correlate this response to a series of feto-placental velocimetric parameters and clinical variables. METHODS: In 25 singleton pregnancies, feto-maternal Doppler velocimetry was performed before and after acute maternal hyperoxygenation. RESULTS: Ten fetuses (40%) exhibited an increase of middle cerebral artery Pulsatility Index (PI) >20% after O2 (Responders), while in 15 fetuses PI did not change relevantly (Nonresponders). Non-responder fetuses showed a higher prevalence of reverse flow in umbilical artery (6/15 vs 0/10: p<0.03) and a slight, but not significant, higher percentage with reversed flow in inferior vena cava (% of A). Also the prevalence of a % of A greater than 95th confidence interval was higher in Non-responders (13/15 vs 4/10; p<0.04). Finally the Responder fetuses showed higher peak velocities in the cardiac outflows, even if the difference reached a statistical significance only for the pulmonary artery. The outcome of the two groups did not differ significantly. CONCLUSIONS: Our results seem to prove an ability of O2 test in selecting a group of AREDV fetuses characterized by a higher degree of hemodynamic deterioration and hence 'placed' in a more advanced step of the pathological process leading to overt cardiac decompensation, even if the clinical application of such a test seems to be still of limited value.


Assuntos
Pressão Sanguínea , Retardo do Crescimento Fetal/fisiopatologia , Oxigênio/administração & dosagem , Diástole , Feminino , Humanos , Gravidez , Reologia , Artérias Umbilicais
10.
Recenti Prog Med ; 86(9): 341-4, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7569294

RESUMO

Endocrine changes occur during the normal aging process. These include alterations in GH, TSH and, to a lesser extent, PRL secretion. Pyrodistigmine (PD) increases basal GH secretion in a widely variable manner and partially reverses the blunted GH response to GHRH found in elderly subjects. The aims of this study were to verify the finding of a paradoxical GH response to TRH (200 micrograms iv) and to evaluate the effect of priming with PD (120 mg orally) on basal and TRH-stimulated GH, TSH and PRL secretion in 7 euthyroid subjects (aged 75-96 years). Hormonal responses after control saline and PD were also evaluated. PD did not modify TSH or PRL responses to TRH. A slight increase in GH secretion was observed after PD. A clear-cut increase in GH levels after TRH was found in 4 out of 7 subjects. TRH-induced GH secretion was significantly increased by pretreatment with PD. Functional abnormalities in the neuroendocrine control of GH secretion in aging could explain, at least in part, the appearance of GH release after TRH. Cholinergic neurotransmission, which is thought to be stimulated by PD administration, seems to be involved in the non-specific GH release after TRH administration in elderly subjects.


Assuntos
Envelhecimento , Hormônio do Crescimento/metabolismo , Prolactina/metabolismo , Hormônio Liberador de Tireotropina/farmacologia , Tireotropina/metabolismo , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Inibidores da Colinesterase/farmacologia , Feminino , Humanos , Masculino , Brometo de Piridostigmina/farmacologia
11.
Eur J Obstet Gynecol Reprod Biol ; 54(1): 7-11, 1994 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-8045335

RESUMO

Twenty-one pregnancies in 16 women who conceived after cardiac valve replacement were reviewed. Oral anticoagulants were discontinued before conception or as soon as possible for subcutaneous heparin treatment (8000-14,000 IU every 8-12 h) and resumed in the second trimester until the last period of pregnancy when oral anticoagulants were replaced again by heparin. No therapeutic abortion was performed. The spontaneous abortion rate was found to be 14.3% (3/21). Preterm delivery (< or = 37 weeks) and low birth weight babies (< 2500 g) were 29.4% (5/17) and 35.3% (6/17), respectively, significantly more frequent than those of the control group (P < 0.02 and P < 0.0005). No significant statistical difference was found when the rate of spontaneous abortion [14.3% (3/21)] and the rate of fetal growth retardation [11.8% (2/17)] were compared with the control group. The majority of thromboembolic events (6/7) occurred during heparin regimen in three mothers; one of them subsequently died. No coumarin embryopathy was observed and the physical and mental development in the 16 surviving children was good. This study confirms: (1) the increased rate of preterm delivery and infants weighing < 2500 g; (2) the increased risk of maternal thrombosis related to heparin use; and (3) the good follow-up in the surviving children.


Assuntos
Próteses Valvulares Cardíacas , Complicações na Gravidez , Resultado da Gravidez , Aborto Espontâneo/epidemiologia , Adulto , Peso ao Nascer , Anormalidades Congênitas/epidemiologia , Feminino , Humanos , Mortalidade Infantil , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Tromboembolia/epidemiologia
12.
Ann Sclavo ; 17(5): 641-59, 1975.
Artigo em Italiano | MEDLINE | ID: mdl-1231651

RESUMO

An account is given about the results of investigations carried out in repeatedly transfused patients. We observed an increased presence of the antileucocyte antibodies in relation to the repeatedly transfused patients. The work was extended also to the repeatedly pregnancies; in this research it was also observed a sensibly increased presence of the antileucocyte antibodies in relation with the number of the pregnancies.


Assuntos
Anticorpos/isolamento & purificação , Leucócitos/imunologia , Testes de Aglutinação , Formação de Anticorpos , Especificidade de Anticorpos , Doadores de Sangue , Teste de Coombs , Testes Imunológicos de Citotoxicidade , Feminino , Antígenos HLA , Testes de Hemaglutinação , Humanos , Gravidez , Fatores de Tempo
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