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1.
J Chromatogr B Analyt Technol Biomed Life Sci ; 854(1-2): 57-62, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17452031

RESUMO

A new method involving zinc sulphate deproteinization was developed to study short chain fatty acids (SCFA) production in the colon and subsequent occurrence of SCFA in blood. SCFA were baseline separated in a 30 min cycle using ion-exclusion chromatography and detected by mass spectrometry. Concentrations could be measured down to 10 microM and isotopomeric distributions could be assessed, enabling the conduction of tracer studies to study changes in SCFA synthesis. The applicability of the method was tested in an extensively characterized pig model yielding portal SCFA concentrations ranging from 70 microM (butyric acid) to 150 microM (propionic acid) to 440 microM (acetic acid) prior to butyrate tracer infusion, reaching butyric acid isotopic steady state within 2 h.


Assuntos
Cromatografia em Gel/métodos , Ácidos Graxos/síntese química , Espectrometria de Massas/métodos , Animais , Isótopos , Suínos
2.
Lab Anim ; 35(1): 101-10, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11201286

RESUMO

A method was developed to measure metabolic fluxes across either portally-drained viscera (PDV) and liver or kidney and hindquarter (HQ) in anesthetized mice. The method includes a primed-constant infusion of ketamine-medetomidine anaesthesia to stabilize the mice for the surgical procedures. For measurement of metabolic fluxes across PDV and liver, blood sampling catheters were inserted in the carotid artery, portal vein and hepatic vein and infusion catheters in the jugular vein and mesenteric vein. For measurement of metabolic flux across kidney and HQ, blood sampling catheters were inserted in the carotid artery, renal vein and caval vein and infusion catheters in the jugular vein and abdominal aorta. 14C-PAH was infused to enable plasma flow measurement using an indicator dilution method. In addition, we developed a blood sampling procedure without waste of blood. We measured plasma flow and metabolic fluxes across PDV, liver, kidney and HQ. Mean plasma flow in post-absorptive mice was: PDV: 0.9+/-0.2, liver: 1.2+/-0.3, kidney: 1.0+/-0.1, HQ: 1.1+/-0.3 ml/10 g body weight (b.w.)/min. Significant glutamine release by the HQ and uptake of glutamine by the kidney and PDV was observed. In PDV, citrulline is produced from glutamine and is in turn used by the kidney for the production of arginine. In conclusion, the described model enables measurement of metabolic fluxes across PDV, liver, kidney and HQ in mice. The availability of such a small animal model allows the potential for measuring metabolic parameters in transgenic and knockout mice, and therefore may lead to an important refinement in metabolic research.


Assuntos
Membro Posterior/metabolismo , Rim/metabolismo , Fígado/metabolismo , Sistema Porta/metabolismo , Vísceras/metabolismo , Aminoácidos/metabolismo , Animais , Arginina/metabolismo , Velocidade do Fluxo Sanguíneo , Cateterismo/métodos , Citrulina/metabolismo , Feminino , Glutamina/metabolismo , Masculino , Camundongos , Modelos Animais , Fluxo Sanguíneo Regional , Organismos Livres de Patógenos Específicos
3.
Lab Anim ; 30(4): 347-58, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8938622

RESUMO

A method was developed to measure metabolic fluxes simultaneously across the portally-drained viscera (PDV), liver, spleen, kidney and hindquarter (HQ) in the conscious pig (20-25 kg). For this purpose, sampling catheters were implanted in the abdominal artery, portal vein, hepatic vein, splenic vein, renal vein and caval vein. Further, two extra infusion catheters were implanted in the splenic vein and abdominal artery. These allow continuous infusion of para-aminohippuric acid (PAH), providing a method for estimating the plasma flow of the liver, PDV, spleen, kidney and HQ. To minimize the postoperative recovery period of the pigs, great attention was paid to the housing conditions. After a recovery period of seven days, pigs were used for experiments twice a week. During the three weeks experimental period, food intake, body temperature, weight gain, blood gas data and plasma flow were monitored. Mean plasma flow was: liver 52 +/- 6, PDV 40 +/- 5, HQ 20 +/- 2, spleen 4 +/- 1 and kidneys 15 +/- 2 ml/kg body weight/min. These data were characteristic for a pig in a conscious normal resting and unstressed state. The long-term patency rate of the sampling catheters was very high (ranging from 75% to 100%). This was probably due to the prevention of catheter-related infections using a gentamicin (20 mg/ ml), alpha-chymotrypsin (225 U/ml) solution as catheter filling. We conclude that this model enables simultaneously liver, PDV, intestine, spleen, liver, kidney and HQ flux measurement of many metabolic substances in the conscious pig.


Assuntos
Rim/irrigação sanguínea , Fígado/irrigação sanguínea , Sistema Porta , Baço/irrigação sanguínea , Suínos/metabolismo , Aminoácidos de Cadeia Ramificada/sangue , Amônia/sangue , Animais , Velocidade do Fluxo Sanguíneo , Cateterismo , Feminino , Alimentos , Glutamina/sangue , Veias Hepáticas , Veia Porta , Veias Renais , Veia Esplênica , Ácido p-Aminoipúrico
4.
Clin Nutr ; 14(6): 354-64, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16843957

RESUMO

Carbohydrates, added to a protein meal, are known to enhance the efficiency of dietary protein utilisation. However, the respective roles of the gut and liver in relation to this enhanced efficiency are not known. Therefore, we studied amino-acid, ammonia, urea, glucose and lactate fluxes for 6 h across the portal drained viscera and liver in conscious, multi-catheterised pigs of approximately 25 kg body weight after receiving a protein meal with added carbohydrates, a pure protein meal or a control meal. Additional carbohydrate caused a net glucose efflux in the portal drained viscera and increased arterial blood insulin levels. The appearance of amino-acids in the portal blood declined by some 30%, in spite of the dietary true amino-acid digestibility being approximately 95%. Liver uptake of most amino-acids was lower and there was a lower liver urea production. Finally, there was a smaller postprandial increase in the arterial blood concentration for most of the amino-acids. The results of this study suggest that inclusion of maltodextrin in the diet increases the net retention of meal-derived amino-acids in the portal drained viscera. The lower urea production and liver amino-acid uptake suggest a lower nitrogen loss. The gut could be an important site for nitrogen retention induced by the addition of carbohydrates to a protein meal.

5.
Acta Obstet Gynecol Scand ; 72(5): 344-6, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8392262

RESUMO

OBJECTIVE: To compare actual and calculated gestational age in pregnancies conceived by in-vitro fertilisation. METHODS: In 36 healthy women conceiving by in-vitro fertilisation an equation described for use in a Nordic population was used for calculating gestational age from the biparietal diameter and femur length at a routine 18-19 week scan. This was compared to actual gestational length estimated from the day between oocyte retrieval and embryo transfer. RESULTS: The mean difference amounted to -0.86 days with a standard deviation of 2.86 days, a range of -5 to +6 days and a 95% confidence interval -0.11 to 1.83 (t = 1.806, df = 35, p = 0.8). Correlation between the two methods was highly significant. CONCLUSION: The equation used allows prediction of term with sufficient accuracy for general use in our population.


Assuntos
Antropometria , Fertilização in vitro , Feto/anatomia & histologia , Ultrassonografia Pré-Natal , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez , Valores de Referência
6.
Acta Psychiatr Scand ; 83(5): 329-33, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1853723

RESUMO

This study describes the psychophysiological results of a larger investigation of the clinical, morphological, psychometric and psychophysiological aspects of dementia of the Alzheimer type and depression in elderly patients. Healthy volunteers provided a further measure of control. It was found that widely used clinical rating scales delineated the 3 groups of subjects to a significant degree. The average frequency of the electroencephalogram (EEG), the P2-N2 peak-to-peak amplitude and P3 latency of the auditory evoked potential and a characteristic downward shift of the EEG power spectrum differed significantly between demented patients, depressive patients and normal controls. The higher total power in the EEG of the dementia group did not prove statistically significant, probably because of the small numbers. Other psychophysiological measures such as skin conductance level (SCL) and skin temperature (ST) did not reveal statistically significant differences between the groups. Thus, certain psychophysiological measurements may become valuable in the differential diagnosis of these disorders.


Assuntos
Nível de Alerta/fisiologia , Demência/fisiopatologia , Transtorno Depressivo/fisiopatologia , Eletroencefalografia , Idoso , Idoso de 80 Anos ou mais , Sistema Nervoso Autônomo/fisiopatologia , Córtex Cerebral/fisiopatologia , Demência/diagnóstico , Demência/psicologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Potenciais Evocados Auditivos/fisiologia , Feminino , Resposta Galvânica da Pele/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Processamento de Sinais Assistido por Computador , Temperatura Cutânea/fisiologia
7.
Agents Actions ; 30(1-2): 195-7, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2371922

RESUMO

In the present study we investigated the possible role of neutrophils and the endothelium in the induction of hyperreactivity of pig coronary arteries to histamine. Histamine caused a dose-dependent contraction of isolated pig coronary arteries. The maximal contraction to histamine was reduced in preparations from which the endothelium had been removed. Pre-incubation of intact coronary arteries with isolated neutrophils had no influence on the contractile response to histamine. However, when the same experiments were performed with coronary arteries without endothelium, the maximal contraction to histamine was increased. Incubation with scavengers and inhibitors of the enzymes, lipoxygenase or cyclo-oxygenase, provided evidence for a role of lipoxygenase products in the induction of hyperreactivity to histamine by neutrophils in the pig coronary artery.


Assuntos
Vasos Coronários/fisiologia , Histamina/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Neutrófilos/fisiologia , Animais , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Técnicas In Vitro , Contração Muscular/efeitos dos fármacos , Suínos
8.
Br J Clin Pharmacol ; 30 Suppl 1: 156S-158S, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2125232

RESUMO

The possible role of neutrophils and the endothelium in the induction of hyperreactivity of the pig coronary artery to histamine was studied. In pig isolated coronary arteries histamine caused a concentration-dependent contraction; maximal contraction to histamine, however, was reduced in endothelium-denuded arteries. Pre-incubation of intact coronary arteries with isolated neutrophils did not affect the contractile response to histamine, while pre-incubation of endothelium-denuded arteries induced a hyperreactivity to histamine. This induction of hyperreactivity to histamine by neutrophils in pig coronary arteries seems to be mediated by lipoxygenase products, since it could be prevented by pre-incubation of the preparations with lipoxygenase inhibitors, but not with inhibitors of cyclo-oxygenase or with scavengers.


Assuntos
Vasos Coronários/fisiologia , Histamina/farmacologia , Lipoxigenase/metabolismo , Músculo Liso Vascular/fisiologia , Neutrófilos/fisiologia , Animais , Endotélio Vascular/fisiologia , Técnicas In Vitro , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Suínos
9.
Agents Actions ; 27(1-2): 158-9, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2750587

RESUMO

Histamine produced a dose-dependent increase in heart rate, myocardial contractility and coronary flow in the isolated guinea-pig heart using a modified Langendorff procedure. Intraperitoneal treatment of the guinea pigs with E. coli endotoxin, 4 days prior to the experiment, enhanced the positive chronotropic and flow-increasing effect of histamine. The increased response to histamine appeared to be H1-receptor mediated, the positive chronotropic response is attributed to H2-receptors. These results indicate that bacterial endotoxin increases the reactivity of the coronary vascular system of the guinea-pig to histamine.


Assuntos
Circulação Coronária/efeitos dos fármacos , Endotoxinas/toxicidade , Histamina/farmacologia , Animais , Cobaias , Frequência Cardíaca/efeitos dos fármacos , Masculino , Contração Miocárdica/efeitos dos fármacos , Receptores Histamínicos/fisiologia
10.
Eur J Pharmacol ; 147(3): 421-9, 1988 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-2837397

RESUMO

The beta-adrenergic binding sites on splenic lymphocyte membranes of the guinea pig were characterized with the radio-ligand [125I]cyanopindolol and showed a maximal number of binding sites (Bmax) of 125 fmol/mg protein and an affinity (Kd) of 170 pM. The potency of various beta-adrenoceptor antagonists to compete for [125I]cyanopindolol binding suggested that the receptor is of the beta 2 subtype. Endotoxin (1 mg/kg) induced a 35% decrease in the number of beta-adrenergic binding sites on lymphocytes, 4 days after i.p. administration. The reduction in the number of beta-adrenoceptors on the lymphocytes was accompanied by a 30% decrease in the relaxation of isolated guinea pig tracheal spirals to isoprenaline and a 20% reduction in the number of beta-adrenergic binding sites in peripheral lung tissue. The endotoxin-induced deterioration of the beta-adrenergic system in the respiratory airways was completely prevented by splenectomy. It is concluded that the spleen, and or cells or products derived from the spleen, are involved in the changes of the beta-adrenergic system in the respiratory airways and lymphocytes.


Assuntos
Endotoxinas/toxicidade , Linfócitos/metabolismo , Receptores Adrenérgicos beta/metabolismo , Hipersensibilidade Respiratória/fisiopatologia , Baço/fisiologia , Animais , Membrana Celular/metabolismo , Cobaias , Masculino , Hipersensibilidade Respiratória/etiologia , Hipersensibilidade Respiratória/metabolismo , Traqueia/fisiopatologia
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