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1.
J Dairy Sci ; 101(12): 11413-11420, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30316589

RESUMO

In the present study, we tested the hypothesis that overconditioning in dairy cows at the end of the dry period leads to infiltration of fat and alterations of the insulin secretory capacity of the pancreas. Pregnant Holstein Friesian dairy cows were selected based on body condition score (BCS) at the start of the dry period. Body condition score varied between cows to have optimal conditioned (2.5 < BCS ≤3.5, n = 5) and overconditioned (3.5 < BCS ≤5, n = 5) cows. All animals underwent an intravenous glucose tolerance test (IVGTT) at an average of 260 d of gestation to measure the pancreatic insulin secretory capacity and assess peripheral insulin sensitivity regarding glucose metabolism. Eight days after the IVGTT, animals were slaughtered. The pancreas was dissected and weighed and tissue samples were taken for histological analysis. Results revealed that overconditioning in dairy cows led to fat infiltration in the pancreas and an increase in size of pancreatic islets expressed relative to the total area of pancreatic tissue. In addition, results revealed a positive correlation between serum fatty acid concentration and peak insulin concentration and area and number of pancreatic islets expressed relative to the total area of pancreatic tissue. The IVGTT revealed that overconditioned animals have a higher insulin secretory capacity of the pancreas, as demonstrated by higher peak insulin concentration, higher acute insulin response to glucose, and higher area under the curve (AUC) for insulin compared with optimal conditioned cows. A higher AUC for glucose during the first 60 min following administration of the glucose bolus in overconditioned cows indicates an insulin-resistant state regarding glucose metabolism. Our results suggest that the pancreas of overconditioned dairy cows at the end of gestation compensates for the concomitantly elevated level of peripheral insulin resistance by greater secretion of insulin.


Assuntos
Bovinos/metabolismo , Gorduras/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Pâncreas/metabolismo , Animais , Ácidos Graxos/metabolismo , Feminino , Teste de Tolerância a Glucose , Resistência à Insulina , Lactação , Gravidez
2.
J Dairy Sci ; 98(7): 4580-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25958289

RESUMO

The objective of the present research was to determine the insulin response of the glucose and fatty acid metabolism in dry dairy cows with a variable body condition score (BCS). Ten pregnant Holstein Friesian dairy cows (upcoming parity 2 to 5) were selected based on BCS at the beginning of the study (2mo before expected parturition date). During the study, animals were monitored weekly for BCS and backfat thickness and in the last 2wk, blood samples were taken for determination of serum nonesterified fatty acid (NEFA) concentration. Animals underwent a hyperinsulinemic euglycemic clamp test in the third week before the expected parturition date. The hyperinsulinemic euglycemic clamp test consisted of 4 consecutive insulin infusions with increasing insulin doses: 0.1, 0.5, 2, and 5mIU/kg per minute. For each insulin infusion period, a steady state was defined as a period of 30min where no or minor changes of the glucose infusion were necessary to keep the blood glucose concentration constant and near basal levels. During the steady state, the glucose infusion rate [steady state glucose infusion rate (SSGIR) in µmol/kg per minute] and NEFA concentration [steady state NEFA concentration (SSNEFA) in mmol/L] were determined and reflect the insulin response of the glucose and fatty acid metabolism. Dose response curves were created based on the insulin concentrations during the steady state and the SSGIR or SSNEFA. The shape of the dose response curves is determined by the concentration of insulin needed to elicit the half maximal effect (EC50) and the maximal SSGIR or the minimal SSNEFA for the glucose or fatty acid metabolism, respectively. The maximal SSGIR was negatively associated with variables reflecting adiposity of the cows (BCS, backfat thickness, NEFA concentration during the dry period, and absolute weight of the different adipose depots determined after euthanasia and dissection of the different depots), whereas the EC50 of the glucose metabolism was positively associated with these variables. These results reflect a decreased insulin sensitivity and a decreased insulin responsiveness of the glucose metabolism in overconditioned dry dairy cows. The minimal SSNEFA and the EC50 of the fatty acid metabolism were not associated with variables reflecting adiposity of the cows, meaning that the insulin response of the fatty acid metabolism was not associated with the level of fat accumulation in dry dairy cows. Additionally, within individual cows, the EC50 of the glucose metabolism was higher than the EC50 of the fatty acid metabolism, meaning that the response of the fatty acid metabolism occurs at lower insulin concentrations compared with the response of the glucose metabolism. It can be concluded that a negative association exists between the level of fat accumulation in pregnant dairy cows at the end of the dry period and the insulin response of the glucose metabolism.


Assuntos
Glicemia/metabolismo , Insulina/sangue , Metabolismo dos Lipídeos , Tecido Adiposo/metabolismo , Animais , Bovinos , Relação Dose-Resposta a Droga , Eutanásia Animal , Ácidos Graxos não Esterificados/sangue , Feminino , Técnica Clamp de Glucose , Hiperinsulinismo/sangue , Gravidez
3.
Animal ; 9(9): 1490-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25952084

RESUMO

The objective of the present retrospective cohort study was to evaluate potential associations between environmental factors and dam characteristics, including level of milk production during gestation, and insulin traits in newborn Holstein calves. Birth weight and gestational age of the calves at delivery were determined. On the next day, heart girth, wither height and diagonal length of both the calves and their dams were measured. Parity, body condition score and age at calving were recorded for all dams. For the cows, days open before last gestation, lactation length (LL), length of dry period (DP) and calving interval were also calculated. The magnitude and shape of the lactation curve both quantified using the MilkBot model based on monthly milk weights, were used to calculate the amount of milk produced during gestation. Using the same procedure, cumulative milk production from conception to drying off (MGEST) was calculated. A blood sample was collected from all calves (n=481; 169 born to heifers and 312 born to cows) at least 5 h after a milk meal on day 3 of life to measure basal glucose and insulin levels. In addition, an intravenous glucose-stimulated insulin secretion test was performed in a subset of the calves (n=316). After descriptive analysis, generalized linear mixed models were used to identify factors that were significantly associated with the major insulin traits (Insb, basal insulin level; QUICKI, quantitative insulin sensitivity check index; AIR, acute insulin response; DI, disposition index) of the newborn calves. The overall average birth weight of the calves was 42.7 ± 5.92 kg. The insulin traits were significantly associated with gender and season of birth when data of all calves were analyzed. In addition, the insulin traits in calves born to cows were significantly associated with MGEST, DP and LL. The Insb was estimated to be higher in calves born to the cows having passed a higher MGEST (P=0.076) and longer DP (P=0.034). The QUICKI was estimated to be lower in calves born to the cows having passed a higher MGEST (P=0.030) and longer DP (P=0.058). Moreover, the AIR (P=0.009) and DI (P=0.049) were estimated to be lower in male compared with female calves. Furthermore, the AIR (P=0.036) and DI (P=0.039) were estimated to be lower in calves born to cows having passed a longer LL. The decisive effects of MGEST, DP and LL in cows on the insulin traits of their calves may provide a basis for developing managerial interventions to improve metabolic health of the offspring.


Assuntos
Animais Recém-Nascidos/fisiologia , Resistência à Insulina/fisiologia , Insulina/metabolismo , Lactação/fisiologia , Leite/estatística & dados numéricos , Animais , Intervalo entre Nascimentos , Peso ao Nascer/fisiologia , Constituição Corporal/fisiologia , Bovinos , Estudos de Coortes , Indústria de Laticínios/métodos , Feminino , Idade Gestacional , Glucose/metabolismo , Coração/anatomia & histologia , Modelos Lineares , Masculino , Tamanho do Órgão , Estudos Retrospectivos
4.
Water Sci Technol ; 45(4-5): 445-52, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11936665

RESUMO

This contribution discusses the feasibility of automatic control for chemicals dosing in activated sludge systems. The evaluation is made on the basis of a full-scale implementation at the Lommel WWTP (Belgium) of an on-line controlled dosage system for iron chloride and external carbon source. The control laws are very simple and allow intuitive adaptation by the plant operators. The control system results in a significant reduction of the chemicals dosage, better effluent results and a lower sludge production. The implementation is furthermore cost-efficient.


Assuntos
Purificação da Água/métodos , Automação/métodos , Carbono/análise , Custos e Análise de Custo , Estudos de Viabilidade , Compostos de Ferro/análise , Sistemas On-Line , Fósforo/análise , Fósforo/isolamento & purificação , Esgotos/química , Ultrafiltração , Purificação da Água/economia , Purificação da Água/instrumentação
5.
Med. cután. ibero-lat.-am ; 30(1): 5-8, ene. 2002. tab, ilus
Artigo em Es | IBECS | ID: ibc-17106

RESUMO

Antecedentes: La pitiriasis versicolor es una micosis cosmopolita causada por Malassezia spp. y sensu lato por M. furfur. Se afectan desde lactantes hasta ancianos, pero hay pocos reportes de su frecuencia en niños. Objetivos: Estudiar los datos clínicos y epidemiológicos de la pitiriasis versicolor en la población pediátrica. Metodología: Estudio retrospectivo y transversal de los pacientes infantiles con pitiriasis versicolor confirmada por estudio micológico de enero a diciembre de 1999. Resultados: Entre 5.160 casos de pitiriasis versicolor se encontraron 797 en menores de 15 años (13,5 per cent) (promedio 8 años) y, de éstos, 92 en lactantes. La localización más frecuente fue la cara, en el 50,2 per cent, el tronco en el 25,68 per cent y las extremidades en el 19,4 per cent, pero también en el cuello en el 4,8 per cent. Conclusiones: La pitiriasis versicolor en niños es frecuente en climas cálidos y húmedos, y predomina en la cara y el tronco. El diagnóstico con hidróxido de potasio es sencillo y barato, y pone en evidencia a Malassezia spp. (AU)


Assuntos
Adolescente , Feminino , Pré-Escolar , Lactente , Masculino , Criança , Humanos , Recém-Nascido , Tinha Versicolor/epidemiologia , Tinha Versicolor/diagnóstico , Micologia , Estudos Transversais , Malassezia/patogenicidade , República Dominicana , Fatores Etários
6.
Water Res ; 35(1): 180-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11257872

RESUMO

Measurement of nitrifiable nitrogen contained in wastewater by combining the existing respirometric and titrimetric principles is reported. During an in-sensor-experiment using nitrifying activated sludge, both the dissolved oxygen (DO) and pH in the mixed liquor were measured, and the pH was controlled at a set-point through titration of base or acid. A combination of the oxygen uptake rate (OUR), which was obtained from the measured DO signal, and the titration data allowed calculation of the nitrifiable nitrogen and the short-term biological oxygen demand (BOD) of the wastewater sample that was initially added to the sludge. The calculation was based solely on stoichiometric relationships. The approach was preliminarily tested with two types of wastewaters using a prototype sensor. Good correlation was obtained.


Assuntos
Amônia/análise , Nitrogênio/análise , Oxigênio/análise , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Água/análise , Técnicas Biossensoriais , Calibragem , Desenho de Equipamento , Concentração de Íons de Hidrogênio , Purificação da Água/instrumentação
7.
Rev Iberoam Micol ; 18(3): 109-12, 2001 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-15487918

RESUMO

BACKGROUND: Pityriasis versicolor is a common world wide mycosis caused by Malassezia spp. and by Malassezia furfur sensu lato. It is uncommon in children and almost always with atypical clinical manifestations. It has been reported as exceptional in children under one year of age. OBJECTIVES: To determine the clinical and epidemiological data of pityriasis versicolor in infants under one year of age. METHODOLOGY: This is a restrospective and transversal study of pityriasis versicolor in the pediatric population studied during one year at the Instituto Dermatologico y Cirugia de Piel in Dominican Republic. Everyone with a Malassezia spp. positive scotch tape test with methylene blue were included. RESULTS: Among 5160 cases of pityriasis versicolor where 797 were children, we found 92 (11%) cases under one year of age. The clinical manifestations were atypical and the most commonly affected zone was the face (81%) and thorax (16%). Less frequently the neck (8.6%) and upper and lower limbs (5%) were affected. CONCLUSIONS: Pityriasis versicolor in children under one year of age is not exceptional in humid and hot climates. The hypochromic lesions are the main clinical manifestation and the most affected site is the face. Diagnosis is easy and cheap with a positive Malassezia spp. scotch tape test with methylene blue.

8.
Biotechnol Bioeng ; 65(3): 265-73, 1999 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-10486124

RESUMO

The on-line estimation of the maximum specific growth rate of autotrophic biomass is addressed in this article. A general nitrification process model, which is valid for any realistic flow pattern, is used to develop the estimation algorithm. Depending on the measurements available, two estimation equations are derived. While both require measuring the nitrification activity of the activated sludge, one requires the additional measurement of the nitrifiable nitrogen concentrations at the two ends of the bioreactor, and the other requires the nitrate nitrogen concentrations at the same locations. The algorithm also requires some stoichiometric and kinetic parameters. However, sensitivity analysis shows that the estimate is insensitive to the parameters other than the autotrophic decay rate. Compared to the existing algorithms, the algorithm developed in this article does not rely on the assumption of ideal flow pattern in the plant and does not require an error-prone estimate of the autotrophic biomass concentration. Experimental and simulation studies show that the algorithm performs well and is robust to influent variations and accidental sludge losses.


Assuntos
Nitrogênio/química , Esgotos/química , Algoritmos , Reatores Biológicos , Cinética , Modelos Químicos , Titulometria
11.
J Int Med Res ; 14(4): 210-6, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3530834

RESUMO

In separate multicentre, randomized, double-blind clinical trials, 1% ciclopirox olamine cream was compared with its cream vehicle and with 1% clotrimazole cream as treatment for tinea corporis and tinea cruris. Patients who demonstrated clinical and mycological findings consistent with the diagnoses of tinea corporis or tinea cruris were included in the study. Clinical and mycological evaluations were made pretreatment, at the end of each of the four weeks of treatment, and weekly for the two weeks immediately following cessation of treatment. In both studies, use of ciclopirox olamine cream resulted in demonstrable improvements after the first week of therapy and in complete clinical and mycological clearing in two thirds of the patients at the end of the treatment period. These results were maintained through the two-week drug-free observation period that followed the end of treatment. Statistically, the results with ciclopirox olamine cream were significantly better than those with the vehicle and were equivalent to those with clotrimazole cream. All treatments were well tolerated.


Assuntos
Antifúngicos/uso terapêutico , Piridonas/uso terapêutico , Tinha/tratamento farmacológico , Administração Tópica , Antifúngicos/administração & dosagem , Ciclopirox , Ensaios Clínicos como Assunto , Clotrimazol/efeitos adversos , Clotrimazol/uso terapêutico , Método Duplo-Cego , Humanos , Piridonas/administração & dosagem
12.
Postgrad Med J ; 61 Suppl 4: 137-41, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3014471

RESUMO

A crude varicella skin-test antigen corresponding to an inactivated partly-purified high-titre varicella Oka-strain vaccine was prepared at Smith Kline-RIT. It was used for a delayed hypersensitivity skin test in 60 healthy adults for determination of their immune status. The findings were analysed according to the presence or absence of humoral antibodies to varicella-zoster virus (VZV), and of a specific cell-mediated immune (CMI) response as measured by the VZV-specific lymphocyte transformation test. The immune status to varicella could be determined in all subjects provided that the amount of antigenic material in the skin-test antigen was sufficiently high. The 2 tests for the CMI response, the delayed hypersensitivity skin test and the lymphocyte transformation test, gave concordant results in both seropositive and seronegative individuals. The inactivated skin-test antigen cannot replace vaccination with the live varicella vaccine since it is unable to induce seroconversion in seronegatives or an antibody booster response in seropositives. Furthermore, seropositive and seronegative subjects showing a negative response to the varicella-zoster-specific lymphocyte transformation test remained negative 2 weeks after the injection of the skin-test antigen.


Assuntos
Anticorpos Antivirais/análise , Varicela/imunologia , Herpes Zoster/imunologia , Herpesvirus Humano 3/imunologia , Antígenos Virais/administração & dosagem , Suscetibilidade a Doenças , Humanos , Hipersensibilidade Tardia , Imunidade Celular , Técnicas Imunoenzimáticas , Ativação Linfocitária , Testes Cutâneos
13.
Am J Trop Med Hyg ; 33(5): 800-4, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6091468

RESUMO

Local heat treatment was tested and found effective in three patients with diffuse cutaneous leishmaniasis (DCL), a form of disease poorly responsive to the usual chemotherapy. A water bath that circulated water through a pad wrapped around the lesion provided a temperature of 39 degrees C to 41 degrees C for a cumulative time of at least 20 hours, over a period of several days. In the DCL patients beneficial effect of heat treatment was documented by pre- and post-treatment biopsies and cultures. Several other patients with ordinary cutaneous leishmaniasis did not respond to the same form of treatment. It was concluded that different strains and/or species of leishmanial parasites vary in their sensitivity to elevated temperature. While local heat treatment may be curative in certain cases of cutaneous leishmaniasis, such therapy is still experimental and should be monitored by quantitative parasitological studies to document its usefulness.


Assuntos
Temperatura Alta/uso terapêutico , Leishmaniose/terapia , Adolescente , Adulto , Anfotericina B/uso terapêutico , Animais , Gluconato de Antimônio e Sódio/uso terapêutico , Biópsia , Pré-Escolar , Feminino , Humanos , Leishmaniose/tratamento farmacológico , Leishmaniose/patologia , Masculino , Pessoa de Meia-Idade
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