RESUMO
The rate of the remodeling of the arterialized saphenous vein conduit limits the outcomes of coronary artery bypass graft surgery (CABG), which may be influenced by endothelial dysfunction. We tested the hypothesis that high stretch (HS) induces human saphenous vein endothelial cell (hSVEC) dysfunction and examined candidate underlying mechanisms. Our results showed that in vitro HS reduces NO bioavailability, increases inflammatory adhesion molecule expression (E-selectin and VCAM1) and THP-1 cell adhesion. HS decreases F-actin in hSVECs, but not in human arterial endothelial cells, and is accompanied by G-actin and cofilin's nuclear shuttling and increased reactive oxidative species (ROS). Pre-treatment with the broad-acting antioxidant N-acetylcysteine (NAC) supported this observation and diminished stretch-induced actin remodeling and inflammatory adhesive molecule expression. Altogether, we provide evidence that increased oxidative stress and actin cytoskeleton remodeling play a role in HS-induced saphenous vein endothelial cell dysfunction, which may contribute to predisposing saphenous vein graft to failure.
Assuntos
Actinas/metabolismo , Células Endoteliais/metabolismo , Estresse Oxidativo , Veia Safena/metabolismo , Estresse Mecânico , Humanos , Espécies Reativas de Oxigênio/metabolismo , Células THP-1RESUMO
AIMS: SCN5A gene encodes the α-subunit of Nav1.5, mainly found in the human heart. SCN5A variants are the most common genetic alterations associated with Brugada syndrome (BrS). In rare cases, compound heterozygosity is observed; however, its functional consequences are poorly understood. We aimed to analyze the functional impact of de novo Nav1.5 mutations in compound heterozygosity in distinct alleles (G400R and T1461S positions) previously found in a patient with BrS. Moreover, we evaluated the potential benefits of quinidine to improve the phenotype of mutant Na+ channels in vitro. MATERIALS AND METHODS: The functional properties of human wild-type and Nav1.5 variants were evaluated using whole-cell patch-clamp and immunofluorescence techniques in transiently expressed human embryonic kidney (HEK293) cells. KEY FINDINGS: Both variants occur in the highly conservative positions of SCN5A. Although all variants were expressed in the cell membrane, a significant reduction in the Na+ current density (except for G400R alone, which was undetected) was observed along with abnormal biophysical properties, once the variants were expressed in homozygosis and heterozygosis. Interestingly, the incubation of transfected cells with quinidine partially rescued the biophysical properties of the mutant Na+ channel. SIGNIFICANCE: De novo compound heterozygosis mutations in SNC5A disrupt the Na+ macroscopic current. Quinidine could partially reverse the in vitro loss-of-function phenotype of Na+ current. Thus, our data provide, for the first time, a detailed biophysical characterization of dysfunctional Na+ channels linked to compound heterozygosity in BrS as well as the benefits of the pharmacological treatment using quinidine on the biophysical properties of Nav1.5.
Assuntos
Síndrome de Brugada/genética , Mutação com Perda de Função , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Sequência de Aminoácidos , Síndrome de Brugada/tratamento farmacológico , Síndrome de Brugada/metabolismo , Células HEK293 , Heterozigoto , Humanos , Mutação com Perda de Função/efeitos dos fármacos , Canal de Sódio Disparado por Voltagem NAV1.5/química , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Mutação Puntual/efeitos dos fármacos , Quinidina/farmacologiaRESUMO
BACKGROUND: Multi-Resistant Organisms (MRO) healthcare-associated infections (HAI) are closely associated with contamination of surfaces. Outsourced companies are usually in charge of both hospital hygiene and environmental hygiene personnel (EHP) supervision, which can result in bias. METHODS: A quasi-experimental study. The intervention was to add the "Hospital Environment Hygiene Nurse" (HEHN). MRO acquired infection rate and MRO acquired colonized rate were calculated, pre and post intervention. Confounding variables: MRO carriage rate upon admission and hospitalisation days median (HDM) were calculated. RESULTS: Median length of stay: 5 days (p=0.85, interquartile range=6 days). Carriage rate upon admission: 4.3% for pre-intervention vs 5.3% post-intervention, dif. (CI 95%): 1% (-1% to 2.9%) p=0.33. MRO acquired infection rate: 4.3% for pre-intervention vs. 2% post-intervention, Standardized Infection Ratio (SIR) (CI 95%): 0.47 (0.25 to 0.87). MRO acquired colonization rate:10.4% for pre-intervention vs. 7.9% post-intervention, SIR (CI 95%): 0.75 (0.53 to 1.07). CONCLUSIONS: As a reinforcement to standard infection control (IC) measures in place, the incorporation of an exclusive, full-time HEHN was significantly useful to reduce MRO HAI.
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AIM: This study sought to determine the role of white adipose tissue (WAT) metabolism in the prevention of insulin resistance (IR) by physical training (PT). MAIN METHODS: Male C57BL/6J mice were assigned into groups CHOW-SED (chow diet, sedentary; n=15), CHOW-TR (chow diet, trained; n=18), CAF-SED (cafeteria diet, sedentary; n=15) and CAF-TR (cafeteria diet, trained; n=18). PT consisted of running sessions of 60 min at 60% of maximal speed conducted five days per week for eight weeks. KEY FINDINGS: PT prevented body weight and fat mass accretion in trained groups and prevented hyperglycemia, hyperinsulinemia, glucose intolerance and IR in the CAF-TR. The CAF-SED group presented higher leptin and free fatty acid and lower adiponectin serum levels compared with other groups. Lipolytic activity (in mmol/10(6) adipose cells) stimulated by isoproterenol increased in CHOW-TR (16347±3005), CAF-SED (18110±3788) and CAF-TR (15837±2845) compared with CHOW-SED (8377±2284). The CAF-SED group reduced FAS activity compared with CHOW-SED and CHOW-TR, reduced citrate synthase activity and increased DGAT2 content compared with other groups. Both trained groups reduced G6PDH activity and increased the expression of p-AMPK (Thr172) compared with sedentary groups. CAF-SED group had lower levels of AMPK, p-AMPK (Thr172), ACC and p-ACC (Ser79) compared with other groups. SIGNIFICANCE: The prevention of IR by PT is mediated by adaptations in WAT metabolism by improving lipolysis, preventing an increase in enzymes responsible for fatty acid esterification and by activating enzymes that improve fat oxidation instead of fat storage.
Assuntos
Tecido Adiposo Branco/metabolismo , Resistência à Insulina/fisiologia , Esforço Físico/fisiologia , Adipócitos/metabolismo , Adiponectina/sangue , Adiposidade , Animais , Ácidos Graxos não Esterificados/sangue , Intolerância à Glucose/prevenção & controle , Hiperglicemia/prevenção & controle , Hiperinsulinismo/prevenção & controle , Isoproterenol/farmacologia , Leptina/sangue , Lipólise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução , Condicionamento Físico Animal , Aumento de PesoRESUMO
We investigated the effect of copper (Cu) overload (20-160 µM/24 h) in two cell lines of human hepatic (HepG2) and pulmonary (A-549) origin by determining lipid and protein damage and the response of the antioxidant defence system. A-549 cells were more sensitive to Cu overload than HepG2 cells. A marked increase was observed in both the cell lines in the nitrate plus nitrite concentration, protein carbonyls and thiobarbituric acid reactive substances (TBARS). The TBARS increase was consistent with an increment in saturated fatty acids at the expense of polyunsaturated acids in a Cu concentration-dependent fashion. Antioxidant enzymes were stimulated by Cu overload. Superoxide dismutase activity increased significantly in both the cell lines, with greater increases in HepG2 than in A-549 cells. A marked increase in ceruloplasmin and metallothionein content in both the cell types was also observed. Dose-dependent decreases in α-tocopherol and ferric reducing ability were observed. Total glutathione content was lower in A-549 cells and higher in HepG2. Calpain and caspase-3 were differentially activated in a dose-dependent manner under copper-induced reactive oxygen species production. We conclude that Cu exposure of human lung- and liver-derived cells should be considered a reliable experimental system for detailed study of mechanism/mechanisms by which Cu overload exerts its deleterious effects.
Assuntos
Cobre/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Calpaína/metabolismo , Caspase 3/metabolismo , Catalase/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ceruloplasmina/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Células Hep G2 , Humanos , Nitratos/metabolismo , Nitritos/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismoRESUMO
The relationship of body weight (BW) with white adipose tissue (WAT) mass and WAT gene expression pattern was investigated in mice submitted to physical training (PT). Adult male C57BL/6 mice were submitted to two 1.5-h daily swimming sessions (T, N = 18), 5 days/week for 4 weeks or maintained sedentary (S, N = 15). Citrate synthase activity increased significantly in the T group (P < 0.05). S mice had a substantial weight gain compared to T mice (4.06 ± 0.43 vs 0.38 ± 0.28 g, P < 0.01). WAT mass, adipocyte size, and the weights of gastrocnemius and soleus muscles, lung, kidney, and adrenal gland were not different. Liver and heart were larger and the spleen was smaller in T compared to S mice (P < 0.05). Food intake was higher in T than S mice (4.7 ± 0.2 vs 4.0 ± 0.3 g/animal, P < 0.05) but oxygen consumption at rest did not differ between groups. T animals showed higher serum leptin concentration compared to S animals (6.37 ± 0.5 vs 3.11 ± 0.12 ng/mL). WAT gene expression pattern obtained by transcription factor adipocyte determination and differentiation-dependent factor 1, fatty acid synthase, malic enzyme, hormone-sensitive lipase, adipocyte lipid binding protein, leptin, and adiponectin did not differ significantly between groups. Collectively, our results showed that PT prevents BW gain and maintains WAT mass due to an increase in food intake and unchanged resting metabolic rate. These responses are closely related to unchanged WAT gene expression patterns.
Assuntos
Animais , Masculino , Camundongos , Tecido Adiposo Branco/metabolismo , Regulação da Expressão Gênica , Condicionamento Físico Animal/fisiologia , Aumento de Peso/genética , Adipogenia/genética , Adiponectina/genética , Marcadores Genéticos/genética , Leptina/genética , Lipogênese/genética , Lipólise/genéticaRESUMO
The relationship of body weight (BW) with white adipose tissue (WAT) mass and WAT gene expression pattern was investigated in mice submitted to physical training (PT). Adult male C57BL/6 mice were submitted to two 1.5-h daily swimming sessions (T, N = 18), 5 days/week for 4 weeks or maintained sedentary (S, N = 15). Citrate synthase activity increased significantly in the T group (P < 0.05). S mice had a substantial weight gain compared to T mice (4.06 ± 0.43 vs 0.38 ± 0.28 g, P < 0.01). WAT mass, adipocyte size, and the weights of gastrocnemius and soleus muscles, lung, kidney, and adrenal gland were not different. Liver and heart were larger and the spleen was smaller in T compared to S mice (P < 0.05). Food intake was higher in T than S mice (4.7 ± 0.2 vs 4.0 ± 0.3 g/animal, P < 0.05) but oxygen consumption at rest did not differ between groups. T animals showed higher serum leptin concentration compared to S animals (6.37 ± 0.5 vs 3.11 ± 0.12 ng/mL). WAT gene expression pattern obtained by transcription factor adipocyte determination and differentiation-dependent factor 1, fatty acid synthase, malic enzyme, hormone-sensitive lipase, adipocyte lipid binding protein, leptin, and adiponectin did not differ significantly between groups. Collectively, our results showed that PT prevents BW gain and maintains WAT mass due to an increase in food intake and unchanged resting metabolic rate. These responses are closely related to unchanged WAT gene expression patterns.
Assuntos
Tecido Adiposo Branco/metabolismo , Regulação da Expressão Gênica , Condicionamento Físico Animal/fisiologia , Aumento de Peso/genética , Adipogenia/genética , Adiponectina/genética , Animais , Marcadores Genéticos/genética , Leptina/genética , Lipogênese/genética , Lipólise/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
AIM: To determine the effect of dietary supplementation with n-3 fatty acids (FA) in paediatric burned patients who had less than 20% of total body surface affected. METHODS: Burned patients were randomly assigned into two groups, one of them received a supplement of n-3 FA during 5 weeks; the other group was considered as not n-3 supplemented burned group. A third group of no burned patients was selected as control. Blood samples were collected at admission and in burned groups at the final of the study. Plasma and erythrocyte phospholipid FA composition and some biochemical parameters related to the clinical evolution: total plasma proteins and C3 and C4 complement proteins were determined. RESULTS: In the early post-burn patients, there is an increase in saturated and monounsaturated FAs in plasma phospholipids, and a decrease in polyunsaturated FAs compared with control. These alterations are in favour of proinflammatory response to burn injury. In n-3 FA supplemented group, these changes were further reverted, and a favourable response in the amount of total plasma proteins and in C3 and C4 proteins of the complement system was demonstrated. CONCLUSION: Dietary n-3 FA supplementation might be beneficial for patients suffering thermal injury.
Assuntos
Queimaduras/dietoterapia , Suplementos Nutricionais , Ácidos Graxos Ômega-3/uso terapêutico , Análise de Variância , Proteínas Sanguíneas/análise , Criança , Pré-Escolar , Ácidos Graxos/sangue , Humanos , Lactente , Fosfolipídeos/sangue , Fosfolipídeos/química , Resultado do TratamentoRESUMO
The induction of neurological signs by immunization of rabbits with gangliosides has been a controversial topic for many years. Recently, Yuki et al. [N. Yuki, M. Yamada, M. Koga, M. Odaka, K. Susuki, Y. Tagawa, et al. Animal model of axonal Guillain-Barré syndrome induced by sensitization with GM1 ganglioside. Ann Neurol 2001;49:712-720.] described an immunization protocol, including keyhole lympet hemocyanin in addition to ganglioside that induced a neurological disease resembling human Guillain-Barré syndrome. We employed this protocol in our laboratory and succeeded in reproducing the disease. Five different experiments were performed during a period of two years by different operators, using different batches of drugs, in a total of 26 rabbits. Despite minor variations in onset time and severity of the induced disease, the model proved to be reproducible. Both gangliosides and keyhole limpet hemocyanin are required for induction of disease.
Assuntos
Gangliosídeos/imunologia , Síndrome de Guillain-Barré/etiologia , Síndrome de Guillain-Barré/imunologia , Imunização/efeitos adversos , Animais , Modelos Animais de Doenças , Masculino , Nervos Periféricos/patologia , Coelhos , Fatores de TempoRESUMO
Anti-GM1 antibodies of the IgG isotype are found in serum from patients with Guillain-Barré syndrome. In normal human sera, anti-GM1 IgM-antibodies are commonly present, but their IgG counterpart has not been previously demonstrated. During routine screening, we found a normal human serum with a high titer of anti-GM1 IgG-antibodies (IgG1 subclass). Affinity estimation by soluble antigen-binding inhibition indicated that they are low-affinity antibodies with IC50 values between one and two orders of magnitude higher than those of anti-GM1 IgG-antibodies from Guillain-Barré patients. Various antibody parameters remained fairly constant for 1 year, in additional serum samples taken at 4-month intervals. Such anti-GM1 IgG1-antibodies were not detected in > 100 other normal serum samples tested, indicating a very low frequency in the general population. The low affinity of these unusually present antibodies could explain the absence of disease, despite their relatively high titer. The significance of this finding in the origin of disease-associated anti-GM1 antibodies is discussed.
Assuntos
Autoanticorpos/sangue , Autoanticorpos/imunologia , Gangliosídeo G(M1)/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Adulto , Afinidade de Anticorpos , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Feminino , Síndrome de Guillain-Barré/sangue , Síndrome de Guillain-Barré/imunologia , HumanosRESUMO
Milk fat is the major source of energy for breastfed infants; it also supplies polyunsaturated fatty acids (PUFAs) essential for the development of brain, retina, and other organs. Maternal nutritional status is critical for the newborn, and little information exists regarding the PUFA status of vulnerable populations living in Southern regions. We studied the relationship between maternal nourishment and milk fatty acid composition. Mother nutritional status (normal, overweight or obese) was estimated on the body mass index. Milk protein, total lipid, and fatty acid composition were determined. Milk protein was not affected by mother's nutritional status. In obese mothers an increase in lipid content, linoleic acid, total n-6 and total PUFAs was observed comparing to the other groups. Disregarding the nutritional status, the ratio n-6/n-3 fatty acids was very high and the 22:6n-3 content was very low, when compared with those of mothers from other countries. This finding led us to urge Public Health officers to promote changes in the dietary habits of nursing women.
Assuntos
Ácidos Graxos Insaturados/análise , Leite Humano/química , Estado Nutricional , Adolescente , Adulto , Argentina , Índice de Massa Corporal , Feminino , Humanos , Fenômenos Fisiológicos da Nutrição MaternaRESUMO
alpha-Hemolysin (HlyA) is a protein toxin (107 kDa) secreted by some pathogenic strains of E. coli. Several studies suggested the relationship between HlyA and lipopolysaccharide (LPS). We have studied experimentally the role of LPS on the stability and function of this toxin. The HlyA conformation in both, LPS-free and LPS-bound forms was investigated by tryptophan fluorescence. Studies about HlyA thermal and chemical denaturation indicated that its stability increased in the presence of LPS. On the other hand, the presence of negative and polar residues on the LPS reduced the tendency of HlyA to self-aggregation, and they may be the reservoir of calcium, cation essential for the lytic action of this toxin on red blood cells. These results suggest that HlyA and LPS are combined mainly via hydrophobic force to form an active toxin which stability is favored by the LPS.
Assuntos
Proteínas de Escherichia coli/química , Proteínas Hemolisinas/química , Lipopolissacarídeos/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Lipopolissacarídeos/química , Ligação Proteica , Conformação Proteica/efeitos dos fármacos , Desnaturação Proteica/efeitos dos fármacos , Espectrometria de FluorescênciaRESUMO
It is well known that simvastatin affects cholesterol synthesis. Furthermore it inhibits growth and proliferation and perturbs fatty acid metabolism in some cell lines. We have studied the effects of simvastatin on the uptake and metabolism of exogenous fatty acid in the human lung adenocarcinoma A549 cells. Simvastatin inhibited the proliferation of A549, and caused an increment in phospholipid/cholesterol ratio due to an increment in phospholipid content without affecting cholesterol content. All the fatty acids were uptaken and metabolized in both control and treated cells. The conversion of palmitic, linoleic and dihomo-gamma-linoleic acids to their metabolites and products/precursor ratios for the desaturation and elongation reactions showed that simvastatin enhanced the Delta5 desaturation step and altered some elongating steps. The machinery for unsaturated fatty acid synthesis in A549 is quite sensitive to simvastatin and its effects could have important implication taking into account that highly unsaturated fatty acids are involved in the regulation of diverse cellular functions by themselves or through their metabolites.
Assuntos
Anticolesterolemiantes/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/metabolismo , Ácido Linoleico/metabolismo , Ácido Palmítico/metabolismo , Sinvastatina/metabolismo , Ácido alfa-Linolênico/metabolismo , Adenocarcinoma , Anticolesterolemiantes/farmacologia , Linhagem Celular , Colesterol/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Ácido Linoleico/química , Neoplasias Pulmonares , Fosfolipídeos/metabolismo , Sinvastatina/farmacologiaRESUMO
The fatty-acid composition of liver lipids from mice infected with Trypanosoma cruzi (clone H510C8C3) or uninfected mice was investigated. The infected animals were treated orally for 30 days, with trifluralin (TFL) or benznidazole (BNZ), each at 100mg/kg.day, or only with the peanut oil used as the drug vehicle. The uninfected mice were also given the peanut oil. The treatments were stopped 10 days before the animals were killed. The liver microsomal lipids of each mouse were isolated and then analysed by gas-liquid chromatography. In terms of the total lipids, untreated infection evoked a significant increase in saturated fatty acids and the members of the n-9 fatty-acid family, with a concomitant decrease in the polyenoates of the n-3 and n-6 fatty-acid series. Each lipid subclass was affected to a different extent, the phospholipids being affected most. All lipid fractions, apart from the cholesterol esters, showed a significant increase in the proportion of n-9 isomers. Infection also produced a marked increase in the absolute amounts of triacylglycerides, cholesterol and cholesterol esters in liver microsomal membranes. After BNZ or TFL treatment, the fatty-acid pattern of mice that had been infected was indistinguishable from that of the control mice. The possible role of desaturase activity in the alterations observed is discussed.
Assuntos
Ácidos Graxos/metabolismo , Microssomos Hepáticos/efeitos dos fármacos , Nitroimidazóis/uso terapêutico , Trifluralina/uso terapêutico , Tripanossomicidas/uso terapêutico , Animais , Doença de Chagas/tratamento farmacológico , Doença de Chagas/metabolismo , Colesterol/metabolismo , Ésteres do Colesterol/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Microssomos Hepáticos/metabolismo , Triglicerídeos/metabolismoRESUMO
Polyunsaturated fatty acids (PUFA) derived from essential fatty acids (EFA) play an important role in prenatal visual and neural development. Protein-energy malnutrition affects PUFA supply, and hence the synthesis of structural lipids during growth. Recently, some physiological studies reported abnormalities in the neurological functions of formula-fed infants relative to breast-fed. The purpose of our study was to assess whether fatty acid composition of the malnourished infant diet modifies plasma and erythrocyte phospholipid fatty acid composition. Three groups of full-term malnourished infants were selected according to their prior feeding. Two groups had received commercial formulas, one of them supplied with linoleic and alpha-linolenic acid, and the other supplied in addition with long chain PUFA from n-3 and n-6 series. The reference group of breast-fed infants was also enrolled. Plasma and erythrocyte phospholipid fatty acid composition was determined by gas-liquid chromatography. Those infants receiving formulas showed in plasma and erythrocyte phospholipids increased values in total saturated and monoethylenic fatty acids, and decreased values in polyunsaturated fatty acids from both n-6 and n-3 series, relative to that of breast-fed infants. These differences were more remarkable in the case of infants who received formula without PUFA. We conclude that in malnourished infants, a nutrient formula enriched with long chain fatty acids of n-6 and n-3 series could be helpful to achieve an erythrocyte and plasma fatty acid pattern similar to that obtained in breast-fed infants.
Assuntos
Aleitamento Materno , Eritrócitos/química , Ácidos Graxos/análise , Alimentos Infantis , Transtornos da Nutrição do Lactente/metabolismo , Fosfolipídeos/química , Estudos de Casos e Controles , Ácidos Graxos Insaturados/análise , Feminino , Humanos , Lactente , Masculino , Fosfolipídeos/sangue , Desnutrição Proteico-Calórica/metabolismoRESUMO
Research on fatty acid metabolism in cultured human larynx tumor cells Hep2 was carried out. The cells were incubated with either a saturated (palmitic) or a polyunsaturated (linoleic, alpha-linolenic and eicosatrienoic (n-6)) radioactive fatty acid (0.66 pM, 24 h). The best incorporation capacity was observed in the linoleic acid followed by alpha-linolenic, palmitic and eicosatrienoic acids. All fatty acids tested were anabolized to higher derivatives within their own family. Palmitic acid was primarily monodesaturated rather than elongated, proving to have a very active A9 desaturase activity. With respect to polyunsaturated acid metabolism, the conversion of alpha-linolenic acid to higher homologs, although better than linoleic acid, occurred far less efficiently than that observed in other non-highly undifferentiated human tumor cells. This impairment in higher polyunsaturated fatty acid biosynthesis, reflected in the low levels of arachidonic acid in the fatty acid composition, would not reside in the A5 desaturation step since Hep2 cells can readily convert eicosatrienoic acid into arachidonic acid. Considering the potential regulatory role of specific polyunsaturated fatty acids in the cell proliferative control, the knowledge of the metabolism of fatty acids in this human tumor cell would be important for designing future experiments in order to clarify the mechanism involved in balance, proliferation and cell death.
Assuntos
Carcinoma Hepatocelular/metabolismo , Ácidos Graxos/metabolismo , Neoplasias Laríngeas/metabolismo , Ácidos Graxos/farmacocinética , Humanos , Células Tumorais CultivadasRESUMO
Polyunsaturated fatty acids (PUFA) derived from essential fatty acids (EFA) play an important role in prenatal visual and neural development. Protein-energy malnutrition affects PUFA supply, and hence the synthesis of structural lipids during growth. Recently, some physiological studies reported abnormalities in the neurological functions of formula-fed infants relative to breast-fed. The purpose of our study was to assess whether fatty acid composition of the malnourished infant diet modifies plasma and erythrocyte phospholipid fatty acid composition. Three groups of full-term malnourished infants were selected according to their prior feeding. Two groups had received commercial formulas, one of them supplied with linoleic and alpha-linolenic acid, and the other supplied in addition with long chain PUFA from n-3 and n-6 series. The reference group of breast-fed infants was also enrolled. Plasma and erythrocyte phospholipid fatty acid composition was determined by gas-liquid chromatography. Those infants receiving formulas showed in plasma and erythrocyte phospholipids increased values in total saturated and monoethylenic fatty acids, and decreased values in polyunsaturated fatty acids from both n-6 and n-3 series, relative to that of breast-fed infants. These differences were more remarkable in the case of infants who received formula without PUFA. We conclude that in malnourished infants, a nutrient formula enriched with long chain fatty acids of n-6 and n-3 series could be helpful to achieve an erythrocyte and plasma fatty acid pattern similar to that obtained in breast-fed infants.
RESUMO
Fatty acid desaturase activities were determined in liver microsomes from calcium-deficient rats and compared to calcium-sufficient ones. The calcium-deprived diet (0.5 g/kg) administered for 60 d caused a 30% inhibition in the delta5 desaturase activity and a 45-55% decrease in delta6 and delta9, respectively, facts that cannot be attributed to a reduction in food intake. In vitro addition of calcium, ethyleneglycol-bis(Beta-aminoethyl ether)N,N-tetraacetic acid, and/or cytosol fractions from control or calcium-deficient rats to microsomes from both groups of animals indicates that the reduced desaturase capacities would be the consequence of an indirect effect of calcium deprivation. The present work shows that the reduced unsaturated fatty acid biosynthesis might be the result of modifications in the physicochemical properties of microsomal membranes. Such changes could also be derived from the inhibition of phospholipase A2 activity induced by calcium deficiency.
Assuntos
Cálcio/deficiência , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Insaturados/metabolismo , Microssomos Hepáticos/metabolismo , Acil Coenzima A/metabolismo , Animais , Cálcio/administração & dosagem , Cálcio/farmacologia , Cálcio da Dieta , Feminino , Crescimento , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Fosfolipases A/metabolismo , Fosfolipases A2 , Ratos , Ratos Wistar , Frações Subcelulares/enzimologia , Frações Subcelulares/metabolismoRESUMO
This article describes a community-based study, Alcohol Outlet Density and Mexican American Youth Violence, funded by the California Wellness Foundation--Violence Prevention Initiative to the prevention Research Center in Berkeley, California. The study was conducted in three northern California cities in 1993-1996. The focus is on the inclusionary planning process in designing and implementing the study. Community members were an integral part in the identification of study questions. As a result, the findings of the study are relevant to community activists in advocating alcohol-related policies. The need for more utilization-based community studies is emphasized.
Assuntos
Alcoolismo/etnologia , Alcoolismo/prevenção & controle , Participação da Comunidade/métodos , Pesquisa sobre Serviços de Saúde/organização & administração , Americanos Mexicanos , Desenvolvimento de Programas/métodos , Projetos de Pesquisa , Publicidade , California , Seguimentos , Humanos , Americanos Mexicanos/educação , Americanos Mexicanos/psicologia , Americanos Mexicanos/estatística & dados numéricos , Avaliação das Necessidades/organização & administração , Técnicas de Planejamento , Apoio à Pesquisa como AssuntoRESUMO
OBJECTIVE: This study examines the relationship between level of acculturation and drinking status among Mexican American males and females in three northern California cities. METHOD: The data analyzed were collected through the use of a telephone survey. The sample size is 932. RESULTS: Our results show that acculturation has a direct effect on drinking status for women in the sample but not for men. At low levels of acculturation, our results show the expected difference in drinking status by gender; with high abstention rates for women and low abstention rates for males. At high levels of acculturation there is a convergence in drinking status with females approximating the proportion of male drinkers in the sample. Additionally, acculturation was associated with "heavier" drinking for females while place of birth was associated with "heavier" drinking for males. CONCLUSIONS: Studies of drinking patterns and related problems need to consider these factors.