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Introducción: La saturación cerebral de oxígeno (SrcO2) es una medida del estado de perfusión y oxigenación. El objetivo ha sido analizar la relación entre la SrcO2 y varios parámetros hemodinámicos y respiratorios. Pacientes y métodos Entre octubre del 2011 y julio del 2012, se intervino a 43 niños que fueron incluidos en un estudio prospectivo, observacional y descriptivo. Se midieron la SrcO2 y la presión arterial media (PAM), y se realizaron gasometrías en sangre arterial y venosa. Se determinaron la saturación arterial (SaO2), la saturación venosa (SvcO2), la presión arterial de oxígeno (paO2) y anhídrido carbónico (paCO2), y el lactato, y se calcularon la paO2/FiO2, el índice de oxigenación (IO) y la extracción tisular de oxígeno (ETO2). Estas medidas fueron correlacionadas con la SrcO2, determinándose además la concordancia (índice Kappa) entre esta variable y las que resultaron significativas en el análisis de correlación. Resultados: La edad y el peso fueron de 27,3 meses y 9,2 kg. Se encontraron una correlación positiva de la SrcO2 con la SvcO2 (r = 0,73, p < 0,01) y con la PAM (r = 0,59, p < 0,01), y una correlación negativa con la ETO2 (r = −0,7, p < 0,01). La SrcO2 no se correlacionó con las variables respiratorias. El análisis de concordancia estableció un índice Kappa aceptable (> 0,4) entre la SrcO2 y la SvcO2, y entre la SrcO2 y la ETO2. Conclusiones: La SrcO2 se relaciona estadísticamente con variables hemodinámicas como la PAM, la SvcO2 y la ETO2, pero no con variables respiratorias (AU)
Introduction: Regional cerebral oxygen saturation (rSO2) is a measure of the general state of perfusion and oxygenation. We aim to analyze the relationship between this and various hemodynamic and respiratory parameters. Patients and methods: Forty-three patients, operated on between October 2011 and July 2012, were included in this prospective observational descriptive study. The following parameters were measured: mean arterial pressure, both arterial and central venous oxygen saturation and partial pressures of oxygen and carbon dioxide, and lactate levels. From these parameters, the oxygenation index and the oxygen extraction ratio were calculated. These measurements were studied to evaluate whether rSO2 correlated significantly with the other parameters. Results: The average age and weight of the patients were 27.3 months and 9.2 kg, respectively. The rSO2 correlated positively with both central venous oxygen saturation (r = 0.73, P<0.01) and mean arterial pressure (r = 0.59, P<0.01), and negatively with the oxygen extraction ratio (r =−0.7, P<0.01). No correlation was found with the respiratory parameters. Concordance analysis established an acceptable Kappa index (> 0.4) between the rSO2 and central venous oxygen saturation, and between the rSO2 and oxygen extraction ratio. Conclusions: Regional cerebral oxygen saturation correlates well with hemodynamic parameters- mean arterial pressure, venous saturation, and the tissue oxygen extraction. However, it does not correlate with respiratory parameters (AU)
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Humanos , Hemodinâmica/fisiologia , Oximetria/métodos , Procedimentos Cirúrgicos Cardíacos/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Estudos Prospectivos , Cuidados Pré-Operatórios/métodosRESUMO
INTRODUCTION: Regional cerebral oxygen saturation (rSO2) is a measure of the general state of perfusion and oxygenation. We aim to analyze the relationship between this and various hemodynamic and respiratory parameters. PATIENTS AND METHODS: Forty-three patients, operated on between October 2011 and July 2012, were included in this prospective observational descriptive study. The following parameters were measured: mean arterial pressure, both arterial and central venous oxygen saturation and partial pressures of oxygen and carbon dioxide, and lactate levels. From these parameters, the oxygenation index and the oxygen extraction ratio were calculated. These measurements were studied to evaluate whether rSO2 correlated significantly with the other parameters. RESULTS: The average age and weight of the patients were 27.3 months and 9.2 kg, respectively. The rSO2 correlated positively with both central venous oxygen saturation (r=0.73, P<.01) and mean arterial pressure (r=0.59, P<.01), and negatively with the oxygen extraction ratio (r=-0.7, P<.01). No correlation was found with the respiratory parameters. Concordance analysis established an acceptable Kappa index (> 0.4) between the rSO2 and central venous oxygen saturation, and between the rSO2 and oxygen extraction ratio. CONCLUSIONS: Regional cerebral oxygen saturation correlates well with hemodynamic parameters - mean arterial pressure, venous saturation, and the tissue oxygen extraction. However, it does not correlate with respiratory parameters.
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Encéfalo/metabolismo , Procedimentos Cirúrgicos Cardíacos , Hemodinâmica , Oxigênio/metabolismo , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Estudos Prospectivos , RespiraçãoRESUMO
Adipose tissue is an endocrine organ that plays an essential role in regulating several metabolic functions through the secretion of biological mediators called "adipokines". Dysregulation of adipokines plays a crucial role in obesity-related diseases. Adiponectin (APN) is the most abundant adipokine accounting for the 0.01% of total serum protein, and is involved in a wide variety of physiological processes including energy metabolism, inflammation, and vascular physiology. APN plasma levels are reduced in individuals with obesity, type 2 diabetes and coronary artery disease, all traits with low-grade chronic inflammation. It is has been suggested that the absence of APN anti-inflammatory effects may be a contributing factor to this inflammation. APN inhibits the expression of tumor necrosis factor-α-induced endothelial adhesion molecules, macrophage-to-foam cell transformation, tumor necrosis factor-α expression in macrophages and adipose tissue, and smooth muscle cell proliferation. It also has anti-apoptotic and anti-oxidant effects, which play a role in its cardioprotective action. This review will focus on APN as an anti-inflammatory, anti-atherogenic and cardioprotective plasma protein.
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Adiponectina/metabolismo , Inflamação/metabolismo , Miocárdio/metabolismo , Adiponectina/química , Animais , Humanos , Imunidade , Miocárdio/patologiaRESUMO
A series of novel 2,4-disubstituted-7-methyl-1,1,3-trioxo-2H,4H-pyrazolo[4,5-e][1,2,4]thiadiazines (PTDs) was prepared starting from a ring of pyrazolo[4,5-e][1,2,4]thiadiazine nuclei with two different alkyl halides obtained by a facile one-pot reaction. The structures of all synthesized compounds were confirmed by 1H- and 13C-NMR, infrared spectra (IR), and mass spectra (MS) spectroscopic analysis. Anti-HIV activity was evaluated and none of the compounds were found to inhibit HIV replication in human T-lymphocyte (MT-4) cell culture.
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Previous studies have sought to associate the Pro12Ala variant of the peroxisome proliferator-activated receptor gamma2 (PPARG2) gene with type 2 diabetes, insulin resistance, and obesity, with controversial results. We have determined the Pro12Ala variant frequency in 370 nondiabetic Mexican Mestizo subjects and in five Mexican Amerindian groups and have investigated its possible association with lipid metabolism, insulin serum levels, and obesity in three of these populations. Two independent case-control studies were conducted in 239 nondiabetic individuals: 135 case subjects (BMI > or = 25 kg/m2) and 104 control subjects (BMI < 25 kg/m2). The PPARG2 Ala12 allele frequency was higher in most Amerindian populations (0.17 in Yaquis, 0.16 in Mazahuas, 0.16 in Mayans, and 0.20 in Triquis) than in Asians, African Americans, and Caucasians. The Pro12Ala and Ala12Ala (X12Ala) genotypes were significantly associated with greater BMI in Mexican Mestizos and in two Amerindian groups. X12Ala individuals had a higher risk of overweight or obesity than noncarriers in Mestizos (OR = 3.67; 95% CI, 1.42-9.48; p = 0.007) and in Yaquis plus Mazahuas (OR = 3.21; 95% CI, 1.27-8.11; p = 0.013). Our results provide further support of the association between the PPARG2 Ala12 allele and risk of overweight or obesity in Mestizos and two Amerindian populations from Mexico.
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Variação Genética/genética , Genética Populacional/métodos , Genótipo , Indígenas Norte-Americanos/genética , PPAR gama/genética , Adulto , Índice de Massa Corporal , Humanos , México , Pessoa de Meia-Idade , Obesidade/genéticaRESUMO
La esofagitis eosinofílica consiste en una inflamacióncrónica del esófago con una rica infiltración eosinófila.Durante años se ha considerado una patologíapoco frecuente causante de disfagia en el niño.Sin embargo, un incremento reciente en el diagnósticode esta enfermedad ha provocado que susciteun novedoso interés y a la vez que se reconsidereel papel inmunológico del esófago. Este artículoes una revisión de las características conocidasde esta enfermedad la cual implica aspectos clínicos,nutricionales, histológicos, endoscópicos, manométricos,e inmunológicos
Eosinophilic esophagitis is a disease characterizedby a marked eosinophilic chronic inflammationof the esophagus. For years it has been considereda rare cause of dysphagia in children but an increaseof its diagnosis in the last years provoked a newinterest and also a revaluation of the immunologicalpaper of the esophagus. This paper is a review ofthe known features of this disease (including clinical,nutritional, histological, endoscopic, manometric andimmunological aspects)
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Criança , Humanos , Esofagite/diagnóstico , Eosinofilia/diagnóstico , Esofagite/etiologia , Eosinofilia/etiologia , Esofagite/terapia , Eosinofilia/terapia , Doença CrônicaRESUMO
Objetivos. El conocimiento de la nutrición artificial es un apartado obligatorio en la formación de los especialistas en medicina intensiva por su importancia en el tratamiento del paciente crítico. En el presente estudio se pretende valorar la formación recibida y el grado de conocimientos adquiridos entre los intensivistas de nuestra área. Métodos. Se llevó a cabo una encuesta en tiempo real entre los intensivistas de cinco hospitales de nuestra región. La encuesta constaba de 29 ítems, divida en tres apartados: formación, conocimientos generales y conocimientos en el paciente crítico. Resultados. Se recogieron 52 encuestas (38 especialistas y 14 médicos residentes, o MIR).De ellos, un 83 por ciento había recibido formación sobre el tema durante el período MIR, pero el 66 por ciento la consideraba insuficiente. Esta opinión era significativamente mayor (p < 0,05) en el grupo MIR. Un 66 por ciento de los encuestados adecuaba las dietas a las características del paciente, pero sólo conocían y manejaban "toda" la gama de productos de cada tipo de nutrición un 25 por ciento en el caso de las dietas orales, un 22 por ciento en el de la nutrición enteral y un 36 por ciento en el de la nutrición parenteral. La nota media (desviación estándar [DE]) en el conocimiento de nutrición en el paciente crítico fue de 6,19 (1,80), significativamente mayor (p < 0,05) en los especialistas que en los MIR. Conclusiones. La formación en nutrición se recibe fundamentalmente en el período MIR, aunque en general se considera que es insuficiente. La mayoría de los profesionales utiliza correctamente las dietas existentes. Por último, el grado de conocimientos es medio, y es significativamente mayor en los profesionales con más experiencia (AU)
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Humanos , Nutrição Parenteral , Hidratação , Nutrição Enteral , Educação Continuada , Unidades de Terapia Intensiva , Alimentação com Mamadeira , Espanha , Inquéritos e Questionários , Competência ClínicaRESUMO
A variable radial coordinate transformation of the phase-only filter (POF) that is dependent on the energy's angular distribution of the target spectrum is used to perform shift- and scale-invariant pattern recognition. The POF of a basic size target and the cumulative energy of its angular distribution are calculated. The filter function is then transformed by means of stretching along the radial coordinate so that the same energy contribution to the correlation peak is provided for any size target. The maximum ratio for recognizing scaled objects is 1:1.5. Computer simulations and optical experiments showing the performances of the filter are presented.
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The effect of distal small bowel resection (DSBR) and/or ursodeoxycholic-acid (UDCA) ingestion on hepatic activities of 3-hydroxy-3-methylglutaryl Coenzyme A (HMG-CoA) reductase and acyl-CoA:cholesterol acyltransferase (ACAT) was studied in rats. The total activity and the activity state of the enzyme HMG-CoA reductase were also determined. DSBR significantly increased the total activity of HMG-CoA reductase. This increase was enhanced when rats were treated with UDCA. The active form of the enzyme was increased by DSBR. However, the ingestion of UDCA did not modify these results. Therefore, the observed increase in the total activity of HMG-CoA reductase in resected-rats after the administration of UDCA was due to an increase in the inactive form of the enzyme. The activity of ACAT was decreased in resected animals. This decrease was greater after the treatment of UDCA in resected rats when compared with the corresponding group of untreated rats with UDCA. We conclude that UDCA ingestion increases the effect of intestinal resection on hepatic HMG-CoA reductase and ACAT activities.
Assuntos
Hidroximetilglutaril-CoA Redutases/metabolismo , Intestino Delgado/cirurgia , Fígado/enzimologia , Microssomos Hepáticos/enzimologia , Esterol O-Aciltransferase/metabolismo , Ácido Ursodesoxicólico/farmacologia , Animais , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos WistarRESUMO
Strain effects have been quantitatively evaluated for a set of 22 compounds including ketones (R(2)CO), carboxamides (RCONH(2)), and N,N-dimethylcarboxamides (RCONMe(2)), where R = Me, Et, i-Pr, t-Bu, 1-adamantyl (1-Ad), in their neutral and protonated forms. To this end, use was made of the gas-phase proton affinities and standard enthalpies of formation of these compounds in the gas phase, as determined by Fourier transform ion cyclotron resonance mass spectrometry (FT ICR) and thermochemical techniques, respectively. The structures of 1-AdCOMe and (1-Ad)(2)CO were determined by X-ray crystallography. Quantum-mechanical calculations, at levels ranging from AM1 to MP2/6-311+G(d,p)//6-31G(d), were performed on the various neutral and protonated species. Constrained space orbital variation (CSOV) calculations were carried out on selected protonated species to further assess the contributions of the various stabilizing factors. Taking neutral and protonated methyl ketones as references, we constructed isodesmic reactions that provided, seemingly for the first time, quantitative measures of strain in the protonated species. A combination of these data with the results of theoretical calculations (which also included several "computational experiments") lead to a unified, conceptually satisfactory, quantitative description of these effects and their physical link to structural properties of the neutral and protonated species.
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Several kynurenine analogues were synthesized and tested as inhibitors of the enzymes kynurenine hydroxylase and/or kynureninase with the aim of identifying new compounds able to inhibit the synthesis of quinolinic acid (an endogenous excitotoxin) and to increase that of kynurenic acid, an endogenous antagonist of ionotropic glutamate receptors. Among these analogues, we selected m-nitrobenzoylalanine (mNBA) as an inhibitor of kynurenine hydroxylase and o-methoxybenzoylalanine (oMBA) as an inhibitor of kynureninase. When administered to rats, mNBA was more potent than oMBA in increasing the content of kynurenine and of kynurenic acid in the brain, blood, liver, and kidney. This confirms that hydroxylation is the main pathway of kynurenine metabolism. Both mNBA and oMBA (50-400 mg/kg i.p.) increased the concentration of kynurenate in hippocampal extracellular spaces (as measured with a microdialysis technique) and, when simultaneously injected, their effects were additive. This biochemical effect was associated with a decrease in locomotor activity in rats and with a protection of audiogenic convulsions in DBA/2 mice. In conclusion, the results of the present experiments indicate the possibility of increasing the neosynthesis of kynurenic acid by inhibiting the enzymes that metabolize kynurenine to 3-hydroxykynurenine or to anthranilic acid. The increased synthesis of kynurenate is associated with behavioral effects such as sedation and protection from seizures, which suggests a functional antagonism of the excitatory amino acid receptors.
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Comportamento Animal/fisiologia , Hidrolases/antagonistas & inibidores , Ácido Cinurênico/metabolismo , Oxigenases de Função Mista/antagonistas & inibidores , Ácido Quinolínico/metabolismo , Alanina/análogos & derivados , Alanina/farmacologia , Animais , Anticonvulsivantes/farmacologia , Interações Medicamentosas , Espaço Extracelular/metabolismo , Hipnóticos e Sedativos/farmacologia , Cinética , Cinurenina/metabolismo , Quinurenina 3-Mono-Oxigenase , Masculino , Ratos , Ratos WistarRESUMO
Intracellular pH (pHi) and Cl-/base exchange activity have been examined in isolated chicken enterocytes, both in the presence and absence of 25 mM HCO3-/5% CO2. Intracellular pH was measured with BCECF, a pH-sensitive carboxyfluorescein derivative. Under resting conditions pHi was 7.17 in Hepes and 7.12 in HCO3(-)-buffered solutions. Cells became more alkaline upon withdrawal of Cl-. Cells depleted of Cl- acidified upon reinstatement of Cl-. These changes were faster in the presence of HCO3- than in its absence. After an alkaline load (removal of HCO3- from the medium) pHi decreases towards base line in the presence of Cl-, but not in its absence. The Cl(-)-dependent pHi changes were prevented by H2DIDS and were unaffected by Na+. The Cl(-)-induced recovery from an alkaline load exhibited simple saturation kinetics, with an apparent Km of 12.5 mM Cl- and maximum velocity of approximately 0.20 pH units min-1. The Cl-/base exchange is functional under resting conditions, as shown by cell alkalinization on exposure to 0.5 mM H2DIDS, both in the presence and in the absence of HCO3-. It is concluded that Cl-/base exchange participates in setting the resting intracellular pH in isolated chicken enterocytes and helps recover from alkaline loads. The exchange operates both in the presence and in the absence of bicarbonate.
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Cloretos/metabolismo , Intestino Delgado/metabolismo , Animais , Soluções Tampão , Galinhas , Concentração de Íons de Hidrogênio , Intestino Delgado/citologia , CinéticaRESUMO
Caecal and colonic uptake of both linoleic acid and cholesterol were studied in rats after distal small bowel resection (DSBR). The results showed that the surgical operation increased the caecal and colonic uptake of linoleic acid. Supplementation with linolenic acid inhibited caecal and colonic uptake of linoleic acid. Experiments carried out in the presence of rotenone and ouabain suggest that facilitated diffusion is the predominant mechanism of caecal and colonic linoleic acid absorption, at least at low concentrations. An increase in caecal and colonic uptake of cholesterol was observed after the surgical operation. The study showed that facilitated diffusion seems to be the mechanism of linoleic acid absorption in the caecum and colon, and that both organ growth and changes in transport function of the epithelial cells of caecum and colon appear to be involved in the adaptive response of the bowel to intestinal resection.
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Ceco/metabolismo , Colesterol/metabolismo , Colo/metabolismo , Absorção Intestinal , Intestino Delgado/cirurgia , Ácidos Linoleicos/metabolismo , Trifosfato de Adenosina/fisiologia , Animais , Transporte Biológico , Ceco/efeitos dos fármacos , Colo/efeitos dos fármacos , Epitélio/metabolismo , Absorção Intestinal/efeitos dos fármacos , Ácido Linoleico , Ácidos Linolênicos/farmacologia , Masculino , Ratos , Ratos EndogâmicosRESUMO
Both linoleic acid and cholesterol uptake were studied in small-intestinal sacs of rats in vitro after distal small-bowel resection (DSBR). The relationship between linoleic acid concentration and its absorption was non-linear at low concentrations and became linear at high concentrations in the three groups of animals. These observations indicate that a concentration-dependent dual mechanism of transport is operative in linoleic acid intestinal uptake. Experiments with rotenone and ouabain suggest that a facilitated diffusion is the predominant mechanism of absorption at low concentrations, whereas at high concentrations simple diffusion is predominant. The apparent kinetic constants of linoleic acid uptake (Kd, Kt, and Vmax) increased after DSBR. The uptake of linoleic acid is, however, influenced by the simultaneous presence of linolenic acid, the inhibition constant being decreased after the surgical operation. After the surgical operation an increase of cholesterol uptake was observed, with a parallel enhancement in the apparent mass-transfer coefficient (Kd). Taken together, these results suggest that both organ growth and changes in transport function of the enterocytes appear to be involved in the adaptive response of the bowel to intestinal resection.
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Colesterol/metabolismo , Absorção Intestinal/fisiologia , Intestino Delgado/cirurgia , Jejuno/metabolismo , Ácidos Linoleicos/metabolismo , Animais , Técnicas In Vitro , Masculino , Ratos , Ratos EndogâmicosRESUMO
The serum lipid composition and the fatty-acid profiles of the major lipid fraction (triglycerides, esterified cholesterol, and phospholipid) of liver and serum were examined 6 weeks after both 50% and 75% distal small bowel resection (DSBR). Total serum lipid content did not modify after DSBR. Esterified cholesterol and phospholipid levels of the serum did not significantly change after the operation. However, a significant increase in both free cholesterol and triglyceride levels was observed after DSBR. Different fatty acid changes in the liver and serum lipid fractions were found after DSBR, with the greatest differences in the hepatic esterified cholesterol fraction. These results suggest that DSBR affects both the lipid composition and the fatty acid composition of major lipid fraction of liver and serum.
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1. The acyl-CoA:cholesterol acyltransferase (ACAT) activity and lipid composition of intestinal microsomal membrane were investigated 6 weeks after both 50 and 75% distal small bowel resection (DSBR). 2. No changes in both microsomal ACAT activity and cholesteryl ester levels were found, while microsomal non-esterified cholesterol content was increased after the surgical operation. 3. The total phospholipid content of the microsomes did not change as a result of DSBR. 4. The microsomal phospholipid fatty acid composition showed a significant increase in saturated fatty acids together with no changes in both total monounsaturated and total polyunsaturated fatty acids after resection. 5. An increase in the levels of linoleic acid accompanied by a decrease in arachidonic acid was found in remnant intestine of resected rats.
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Circulação Êntero-Hepática/fisiologia , Intestino Delgado/cirurgia , Lipídeos de Membrana/metabolismo , Microssomos/metabolismo , Esterol O-Aciltransferase/metabolismo , Animais , Colesterol/metabolismo , Ácidos Graxos/metabolismo , Intestino Delgado/metabolismo , Intestino Delgado/ultraestrutura , Membranas Intracelulares/metabolismo , Jejuno/metabolismo , Jejuno/cirurgia , Jejuno/ultraestrutura , Masculino , Microssomos/ultraestrutura , Fosfolipídeos/metabolismo , Ratos , Ratos EndogâmicosRESUMO
Comparative effects of feeding dietary linoleic (corn oil), oleic (olive oil), alpha-linolenic (soybean oil) and polyunsaturated fatty acids (fish oil) on lipid content and fatty acid composition of major individual phospholipids of rat hearts were examined. Feeding different diets did not result in lipid accumulation in the heart. Total triglyceride, nonesterified fatty acid, cholesteryl ester and phospholipid levels of heart tissue were not affected by the type of dietary fatty acid. However, heart free cholesterol levels decreased in both animals fed the olive and the fish oil diets. The percentage of individual phospholipids, phosphatidylcholine (PC), phosphatidylethanolamine (PE) and cardiolipin (CL) did not modify by changes in the dietary fat composition. Heart tissue from animals fed on olive oil were enriched with 18:1 (n-9 + n-7) fatty acid in all phospholipid fractions. Animals fed corn oil contained higher proportions of 18:2 (n-6) for PC, PE and CL, and the ingestion of the soybean oil diet increased 18:2 (n-6) for PC and CL in the same proportion as the ingestion of the corn oil diet. The levels of 22:6 (n-3) were increased in the fish oil-fed group, accompanied by both a decrease in total (n-6) fatty acids and an increase in total (n-3) fatty acids in the three phospholipid fractions. The 20:5 (n-3) was only detected in these animals. These results show that olive oil is as effective as fish oil in reducing heart cholesterol content and support earlier works suggesting the role of fish oil in preventing cardiovascular disease.
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Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos/análise , Miocárdio/química , Fosfolipídeos/análise , Animais , Colesterol/análise , Óleo de Milho/farmacologia , Óleos de Peixe/farmacologia , Masculino , Azeite de Oliva , Óleos de Plantas/farmacologia , Ratos , Ratos Endogâmicos , Óleo de Soja/farmacologiaRESUMO
The effects of intestinal resection on several intestinal parameters have been studied in the large intestine of rats one month after the surgical operation. The results show that both 50% and 80% distal small bowel resection increased net fluid absorption and mucosal permeability and caused expansion of the intercellular spaces of the large intestine. The increase in net fluid absorption was dependent upon the extent of the intestine removed. The cAMP and cGMP content of cecal and colonic mucosa were significantly reduced after jejunoilectomy. Changes in nucleotide levels were dependent on the length of the intestine resected. On the other hand, mucosa Na,K-ATPase specific activity was only increased in the cecum after 80% intestinal resection. The results are discussed in terms of adaptation to prevent diarrhea.
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Ceco/fisiologia , Diarreia/cirurgia , Intestino Delgado/cirurgia , Adenosina Trifosfatases/metabolismo , Animais , Ceco/ultraestrutura , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Diarreia/fisiopatologia , Íleo/cirurgia , Mucosa Intestinal/metabolismo , Jejuno/cirurgia , Masculino , Ratos , Ratos Endogâmicos , Água/metabolismoRESUMO
The acyl-CoA:cholesterol acyltransferase (ACAT) activity and lipid composition of hepatic microsomal membrane were investigated 6 weeks after both 50 and 75% distal-small-bowel resection (SBR). A significant decrease in hepatic cholesteryl ester levels was observed after SBR, with a significant increase in the cholesteryl ester content of the livers of 75% SBR compared with the 50% SBR. Hepatic total acylglycerols, free cholesterol and phospholipid levels were not modified after the surgical operation. Microsomal free cholesterol was increased after both 50 and 75% SBR. However, a decrease in both microsomal ACAT activity and cholesteryl ester levels were found in microsomes (microsomal fractions) of resected rats, both changes being higher after 75 than after 50% resection. The total phospholipid content of the microsomes did not change after the surgical operation. The microsomal phospholipid fatty acid composition indicated higher changes after 75 than after 50% SBR. These results demonstrated that, in resected animals: (1) the activity of the enzyme responsible for catalysing cholesterol esterification (ACAT) is decreased, and (2) hepatic microsomal free cholesterol does not appear to influence the activity of ACAT.
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Intestino Delgado/fisiologia , Metabolismo dos Lipídeos , Microssomos Hepáticos/metabolismo , Esterol O-Aciltransferase/metabolismo , Animais , Colesterol/metabolismo , Ésteres do Colesterol/metabolismo , Ácidos Graxos/metabolismo , Masculino , Microssomos Hepáticos/enzimologia , Fosfolipídeos/metabolismo , Ratos , Ratos Endogâmicos , Triglicerídeos/metabolismoRESUMO
The activity of 3-hydroxy-3-methylglutaryl coenzyme-A reductase (HMG-CoA red.) has been evaluated in rat jejunal, caecal and colonic mucosa adapting to 50% or 75% distal small bowel resection (SBR). Six wk after surgery, the total activity and the activity state (active form) of the enzyme were determined. The results show that HMG-CoA red. activity was stimulated per organ but not per unit mass in the mucosa adapting to SBR. As a side result, we noted regional differences in the active/total reductase ratio (RA/RT) for HMG-CoA red. that was lower in small intestine compared with that of the large intestine.