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1.
J Dairy Sci ; 102(3): 2698-2702, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30692006

RESUMEN

Horns are living tissue and cows can use their horns for thermoregulatory purposes. We investigated the effect of the presence of horns on the metabolome of milk serum and lipidome of milk fat, to assess the physiological effect of dehorning. Milk sampling took place at low ambient temperatures of -6 to 2°C. Horned and dehorned cows were kept in a mixed herd of Holstein Friesian and Brown Swiss cows. The hypothesis was that horned cows needed to increase their metabolism to compensate for additional heat loss through the presence of their horns. No differences were observed in milk yield, milk solids, and somatic cell counts between horned and dehorned cows. For the milk metabolome, horned cows showed an upregulation of several glucogenic AA that could be transformed into glucose for energy supply and a downregulation of sugar intermediates and γ-glutamylcysteine compared with dehorned cows. The fatty acid (FA) composition in horned cows showed a shift toward decreased odd medium-chain FA (C7:0, C9:0, and C11:0) and increased cis-vaccenic acid (C18:1n-7 cis-11) and stearidonic acid (C18:4n-3). The changes in milk composition related to additional heat loss in horned cows indicate a competition in C3 metabolism for glucose synthesis and de novo FA synthesis under cold stress.


Asunto(s)
Cuernos/fisiología , Metaboloma , Leche/química , Animales , Regulación de la Temperatura Corporal , Metabolismo de los Hidratos de Carbono , Bovinos , Ácidos Grasos/metabolismo , Femenino , Cuernos/cirugía , Lactancia/fisiología , Ácidos Oléicos/metabolismo
2.
Nutr Metab Cardiovasc Dis ; 25(12): 1071-8, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26626084

RESUMEN

A recent meta-analysis by Chowdhury et al. (2014) has disclaimed the association between coronary artery diseases and either circulating blood levels or the intake of total saturated fatty acids (SFA). Scrutiny revealed that two of the eight studies included in the meta-analysis focused on the proportion of pentadecanoic acid (C15:0) and heptadecanoic acid (C17:0) and their impact on cardiovascular disease (CVD) risk. These odd-chain fatty acids are markers for milk or ruminant fat intake. Both studies indicated inverse associations between milk-fat intake and first-ever myocardial infarction. Neither of the two studies described the association between total circulating blood SFA on coronary outcomes. In contrast to the cardioprotective effects of dairy consumption, we expected that an elevated intake of palmitic acid (C16:0) and stearic acid (C18:0) de novo may raise CVD risk. Thus, it is of particular importance to differentiate the effects of individual circulating SFA on cardiovascular outcomes. Excluding the studies that evaluated the association of fatty acids from milk fat and cardiovascular outcomes revealed a positive association of total SFA blood levels and coronary outcome (RR 1.21, CI 1.04-1.40). Therefore, results obtained from studies of C15:0 and C17:0 cannot be mixed with results from studies of other SFA because of the opposite physiological effects of regular consumption of foods rich in C16:0 and C18:0 compared to high intake of milk or ruminant fat. In our opinion, it is vital to analyze the impact of individual SFA on CVD incidence in order to draw prudent conclusions.


Asunto(s)
Enfermedad Coronaria/sangre , Enfermedad Coronaria/epidemiología , Grasas de la Dieta/sangre , Ácidos Grasos/sangre , Humanos
3.
J Dairy Sci ; 95(7): 3938-53, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22720948

RESUMEN

The aim of the present experiment was to test the stimulation ability of peripheral blood mononuclear cells (PBMC) expressed as stimulation index (SI) of newborn calves and of their dams fed a control fat supplement (CON, n=6) or 50 and 100g/d of a CLA-containing fat supplement (CLA50, n=5, and CLA100, n=6, respectively) during the preceding lactation period for 182 d after calving. The total intake of cis-9,trans-11 and trans-10,cis-12 CLA by groups CLA50 and CLA100 amounted to 4 and 8 g/d each, respectively. For this purpose, blood was collected immediately after parturition from calves before and after colostrum intake, and from cows after parturition and 21 d later. The SI was related to the fatty acid composition of erythrocyte and milk lipids and to various hematological and clinical-chemical parameters. Retrospective evaluation revealed that depletion time (i.e., the individual period elapsed between the day of terminating the feeding of the experimental diet in the preceding lactation period and the day of calving) ranged from 190 to 262 d, which corresponded to fetal exposure times of 19 to 102 d. The SI from cows increased significantly by 77 and 55%, within 21 d after calving according to the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) and Alamar Blue assays, respectively. However, feeding of 50 g of the CLA product failed to demonstrate this increase in the MTT assay. Moreover, SI was significantly lower for calves whose dams belonged to the CLA50 group, whereas stimulation ability was comparable for the PBMC from calves whose mothers were treated with CON and CLA100. Plasma metabolites (total bilirubin, total cholesterol, glucose, nonesterified fatty acids, 3-ß-hydroxybutyrate, total protein, and albumin) and hematological parameters (hematocrit, white blood cell profile) were not significantly influenced by dietary treatments of the cows in the preceding lactation period. Although the fatty acid pattern of erythrocyte lipids of cows remained uninfluenced, that of calves showed alterations due to the feeding type of their dams. For example, C16:0 increased significantly from 14.4 to 16.9% of total fatty acid methyl esters, whereas cis-9,trans-11 CLA increased slightly from 0.11 to 0.15% at the same time in calves when their mothers were fed the CLA100 instead of the CON diet. Fatty acid profile of colostrum was significantly different from that of milk after 3 wk for most of the detected fatty acids, but was not influenced by diet type. In conclusion, feeding a CLA-containing fat supplement during the preceding lactation and gestation period exerted effects on the stimulation ability of PBMC from cows and calves for the subsequent parturition. However, CLA dose effects were inconsistent and require further investigation.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Ácidos Linoleicos Conjugados/farmacología , Fenómenos Fisiológicos Nutricionales de los Animales/inmunología , Animales , Animales Recién Nacidos/sangre , Animales Recién Nacidos/inmunología , Animales Recién Nacidos/fisiología , Bovinos/sangre , Bovinos/inmunología , Bovinos/fisiología , Suplementos Dietéticos , Grasas/análisis , Femenino , Hematócrito/veterinaria , Lactancia/metabolismo , Lactancia/fisiología , Lactosa/análisis , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/fisiología , Recuento de Linfocitos/veterinaria , Leche/química , Proteínas de la Leche/análisis , Embarazo
4.
J Cell Biol ; 97(3): 728-36, 1983 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6193128

RESUMEN

A cloned line of mouse hepatoma cells (Hepa-1) responded to treatment with dexamethasone by a 30-80-fold increase in synthesis and secretion of functional haptoglobin. Under the same conditions, the production of albumin was only slightly elevated whereas that of alpha 1-fetoprotein was reduced by 50%. The hormone concentration for half-maximal stimulation of haptoglobin synthesis was between 1 and 2 X 10(-8) M. The time course of induction is characteristic for a glucocorticoid-regulated protein. Cell-free translation of RNA indicated an increase in the amount of functional haptoglobin mRNA that can account for the change in the protein production. To correlate our findings on Hepa-1 cells with those on nontransformed liver cells, we tested the hormonal response of isolated hepatocytes in tissue culture. Haptoglobin was first synthesized and secreted by hepatocytes from 17-19-d-old fetuses. But neither prenatal nor adult hepatocytes showed a dexamethasone-dependent increase in haptoglobin synthesis. However, when several independent clones of hybrid cells formed from adult mouse hepatocytes and rat hepatoma cells were treated with dexamethasone, the synthesis of mouse haptoglobin was in all cases elevated. It appears that haptoglobin expression in mouse liver cells is potentially sensitive to glucocorticoids, but this modulation is manifested only in transformed cells and their derivatives.


Asunto(s)
Haptoglobinas/biosíntesis , Neoplasias Hepáticas Experimentales/metabolismo , Animales , Células Cultivadas , Dexametasona/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Glucagón/farmacología , Haptoglobinas/metabolismo , Células Híbridas/metabolismo , Hígado/metabolismo , Ratones , ARN Mensajero/metabolismo , alfa-Fetoproteínas/biosíntesis
5.
J Cell Biol ; 96(1): 139-50, 1983 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6826644

RESUMEN

Glycoproteins in the plasma membrane of rat hepatoma cells were labeled at their externally exposed tyrosine residues with 131I and at their galactose and sialic acid residues with 3H. The degradation of both isotopes in the total cell protein fraction, in glycoproteins purified by concanavalin A, and in glycoproteins separated on two-dimensional gels was determined. Similarly, the total cellular membrane glycoproteins were metabolically labeled with [35S]methionine and [3H]fucose. The fate of both incorporated labels was followed by lectin chromatography or by precipitation of the proteins with specific antibodies followed by electrophoretic gel separation. In both labeling experiments, the carbohydrate markers were lost from the ligand-recognized fraction with similar kinetics as from the total cell protein fraction. In some glycoprotein species which were separated by two-dimensional gel electrophoresis, the polypeptide portion exhibited up to a twofold slower rate of degradation relative to that of the carbohydrate moiety. This difference is most pronounced in carbohydrate-rich glycoproteins. To corroborate this finding, double-labeled membrane glycoproteins were incorporated into reconstituted phospholipid vesicles which were then transferred via fusion into the plasma membrane of mouse fibroblasts. Both the polypeptide and carbohydrate moieties of the transferred membrane glycoproteins were degraded with the same relative kinetics as in the original hepatoma cells. The rate of degradation is mostly a function of the structural properties of the membrane components as shown by the preservation of metabolically stable fucogangliosides of Reuber H-35 hepatoma cells transferred onto the fibroblasts. The technique of insertion of membrane components into the plasma membrane of another cell should assist in the elucidation of the exact route and mechanism of membrane protein destruction.


Asunto(s)
Glicoproteínas/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Metabolismo de los Hidratos de Carbono , Línea Celular , Fibroblastos , Fucosa/metabolismo , Galactosa/metabolismo , Cinética , Células L , Liposomas , Neoplasias Hepáticas Experimentales , Fusión de Membrana , Metionina/metabolismo , Ratones , Ratas , Ácidos Siálicos/metabolismo
6.
J Cell Biol ; 97(3): 866-76, 1983 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6885923

RESUMEN

Adult mouse hepatocytes respond in vivo to experimentally induced acute inflammation by an increased synthesis and secretion of alpha 1-acid glycoprotein, haptoglobin, hemopexin, and serum amyloid A. Concurrently, the production of albumin and apolipoprotein A-1 is reduced. To define possible mediators of this response and to study their action in tissue culture, we established primary cultures of hepatocytes. Various hormones and factors that have been proposed to regulate the hepatic acute phase reaction were tested for their ability to modulate the expression of plasma proteins in these cells. Acute phase plasma and conditioned medium from activated monocytes influenced the production of most acute phase plasma proteins, and the regulation appears to occur at the level of functional mRNA. Purified hormones produced a significant anabolic response in only a few cases: dexamethasone was found to be effective in maintaining differentiated expression of the cells; and glucagon produced a specific inhibition of haptoglobin synthesis. When cells were treated with a combination of conditioned monocyte medium and dexamethasone, secretion of proteins was markedly reduced. The carbohydrate moieties of all plasma glycoproteins were incompletely modified, apparently as a result of decreased intracellular transport of newly synthesized plasma proteins. Although primary hepatocytes were not phenotypically stable in tissue culture, the cells nevertheless retained a broad response spectrum to exogenous signals. We propose this as a useful system to study the production of plasma proteins and thereby pinpoint the nature and activity of effectors mediating the hepatic acute phase reaction.


Asunto(s)
Proteína C-Reactiva/biosíntesis , Hígado/metabolismo , Albúminas/biosíntesis , Animales , Apolipoproteínas/biosíntesis , Células Cultivadas , Dexametasona/farmacología , Interacciones Farmacológicas , Glucagón/farmacología , Glicoproteínas/biosíntesis , Haptoglobinas/biosíntesis , Hemopexina/biosíntesis , Inflamación/metabolismo , Masculino , Ratones , Monocitos/fisiología , Inhibidores de Proteasas/biosíntesis , Proteína Amiloide A Sérica/biosíntesis , Transferrina/biosíntesis
7.
J Cell Biol ; 102(2): 370-83, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2418029

RESUMEN

Human squamous carcinoma (COLO-16) cells release factors which specifically stimulate the synthesis of major acute-phase plasma proteins in human and rodent hepatic cells. Anion exchange, hydroxyapatite, lectin, and gel chromatography of conditioned medium of COLO-16 cells result in separation into three distinct forms of hepatocyte-stimulating factors (designated HSF-I, HSF-II, and HSF-III) with apparent molecular weights of 30,000, 50,000 and 70,000, respectively. None of the preparations contains detectable amounts of thymocyte-stimulating activity. Each of the three HSF forms stimulates the accumulation of mRNA for alpha 1-antichymotrypsin in the human hepatoma cell line, HepG2. When the same factors were added to primary cultures of adult rat hepatocytes, the expression of the same set of plasma proteins was modulated as by nonfractionated medium. The hormonally induced accumulation of mRNA for acute phase proteins is qualitatively comparable to that occurring in the liver of inflamed rats. Unlike in human cells, in rat liver cells dexamethasone acts additively and synergistically with HSFs. The only functional difference between the three HSF forms lies in the level of maximal stimulation. HSF-I represents the predominant form produced by normal human keratinocytes and closely resembles in molecular size and isoelectric point the activity produced by activated peripheral blood monocytes while the larger molecular weight forms are more prevalent in human as well as mouse squamous carcinoma cells. The observation that HSFs from different sources elicit essentially the same pleiotropic response in hepatic cells led to the hypothesis that the species-specific reaction of adult liver cells to inflammatory stimuli is pre-programmed and that the function of any HSF is to trigger and tune the execution of this fixed cellular process.


Asunto(s)
Carcinoma de Células Escamosas/fisiopatología , Hígado/fisiología , Orosomucoide/biosíntesis , Proteínas/aislamiento & purificación , Animales , Carcinoma de Células Escamosas/análisis , Células Cultivadas , Quimotripsina/antagonistas & inhibidores , Quimotripsina/biosíntesis , Concanavalina A/metabolismo , Fibrinógeno/biosíntesis , Humanos , Interleucina-1/farmacología , Interleucina-6 , Punto Isoeléctrico , Neoplasias Hepáticas Experimentales , Peso Molecular , Proteínas/farmacología , ARN Mensajero/biosíntesis , Ratas , alfa 1-Antiquimotripsina , alfa-Macroglobulinas/biosíntesis
8.
Clin Exp Allergy ; 38(1): 93-102, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18028460

RESUMEN

BACKGROUND: Probiotic bacteria are proposed to alleviate atopic dermatitis (AD) in infants. There are few indications about the effect of probiotics on AD in adults. OBJECTIVE: The purpose of this study was to elucidate the influence of a probiotic drink containing a combination of the probiotics Lactobacillus paracasei Lpc-37, Lactobacillus acidophilus 74-2 and Bifidobacterium animalis subsp. lactis DGCC 420 (B. lactis 420) in healthy volunteers and in patients with AD on clinical and immunological parameters and their detection in feces. METHODS: A double-blind, placebo-controlled, randomized cross-over study was conducted in 15 healthy adults and 15 patients with AD. The probiotic product or placebo was given over 8 weeks. A 2-week washout period was interconnected before the intervention was crossed. At the end of each period, blood and stool samples were collected. In patients, the severity of AD was evaluated using the Scoring of Atopic Dermatitis (SCORAD). RESULTS: L. paracasei and B. lactis were recovered in high numbers in feces after supplementation, whereas L. acidophilus marginally increased. In patients, the SCORAD tended to decrease by 15.5% (P=0.081). Major lymphocyte subsets were not affected by the probiotic intervention. However, CD57(+) increased significantly (P=0.034) in healthy subjects after probiotic intake and was not changed in patients, whereas CD4(+)CD54(+) decreased significantly (P=0.031) in patients with AD and remained uninfluenced in healthy subjects. The expression of CD4(+)CD25(+) T cells was similar in healthy subjects and AD patients. The phagocytic activity of monocytes and granulocytes was significantly increased in healthy subjects after probiotic intervention (P=0.014). CONCLUSION: L. paracasei Lpc-37 and B. lactis 420 are able to colonize the intestine transiently. This study reveals that the probiotics differently modulate peripheral immune parameters in healthy subjects and patients with AD.


Asunto(s)
Dermatitis Atópica/inmunología , Salud , Probióticos , Adulto , Formación de Anticuerpos/inmunología , Bifidobacterium , Dermatitis Atópica/microbiología , Heces/microbiología , Femenino , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Lactobacillus , Linfocitos/inmunología , Masculino
9.
Eur J Clin Nutr ; 62(5): 584-93, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17440520

RESUMEN

OBJECTIVE: It was determined whether a combination of Lactobacillus acidophilus (L. acidophilus) 74-2 and Bifidobacterium animalis subsp lactis DGCC 420 (B. lactis 420) affect the faecal microbiota as well as immunological parameters and blood lipids in healthy adults. DESIGN: A placebo-controlled, double-blinded, randomized crossover trial was conducted. SUBJECTS: Twenty-six healthy volunteers (mean age 25 years) were recruited by advertising in academical buildings. All of them completed the study. METHODS: After 3-week run-in period, half of the volunteers consumed 300 g/day of yoghurt supplement containing probiotic strains L. acidophilus 74-2 and B. lactis 420, and the other half received the placebo product for a period of 5 weeks. The two groups were crossed during the following 5-week period. Blood and faecal samples were collected at the end of each period. The faecal content of probiotic bacteria, faecal short-chain fatty acids (SCFA), serum lipids and plasma immune system biomarkers were evaluated. RESULTS: Faecal proportions of L. acidophilus and of B. lactis increased significantly from 0.02 to 0.19 and 0.4 to 1.4% (P<0.05), respectively. Percentages of granulocytes and monocytes showing phagocytic activity were significantly elevated from 92 to 95% during probiotic intervention, whereas their oxidative burst activity and specific immune parameters remained unaffected. Fecal SCFA and serum cholesterol levels were not influenced by the probiotics. However, serum concentrations of triacylglyceroles decreased significantly by 11.6% (P<0.05) in the probiotic supplementation period. CONCLUSIONS: L. acidophilus and B. lactis were recovered in faeces in significantly elevated numbers after supplementation. They are able to modulate unspecific cellular immune response indicated by the increased phagocytic activity.


Asunto(s)
Bifidobacterium/fisiología , Inmunidad Celular/efectos de los fármacos , Lactobacillus acidophilus/fisiología , Probióticos/farmacología , Adulto , Colesterol/sangre , Recuento de Colonia Microbiana , Estudios Cruzados , Método Doble Ciego , Ácidos Grasos Volátiles/análisis , Heces/química , Heces/microbiología , Femenino , Humanos , Lípidos/sangre , Masculino , Triglicéridos/sangre , Yogur/microbiología
10.
Clin Nutr ; 37(2): 494-504, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28302406

RESUMEN

The potential of fish or fish oil as supplier for eicosapentaenoic acid (EPA, C20:5n3) and docosahexaenoic acid (DHA, C22:6n3) for reducing cardiovascular risk factors and supporting therapy of chronic inflammatory diseases, has been investigated intensively, but our knowledge about the physiological effects of the individual compounds EPA and DHA are limited. STUDY DESIGN: In this double-blind pilot study, thirty-eight patients with defined RA were allocated to consume foods enriched with microalgae oil from Schizochytrium sp. (2.1 g DHA/d) or sunflower oil (placebo) for 10 weeks (cross-over), maintaining the regular RA medication during the study. RESULTS: In contrast to placebo, the daily consumption of DHA led to a decline in the sum of tender and swollen joints (68/66) from 13.9 ± 7.4 to 9.9 ± 7.0 (p = 0.010), total DAS28 from 4.3 ± 1.0 to 3.9 ± 1.2 (p = 0.072), and ultrasound score (US-7) from 15.1 ± 9.5 to 12.4 ± 7.0 (p = 0.160). The consumption of placebo products caused an increase of the n-6 PUFA linoleic acid and arachidonic acid (AA) in erythrocyte lipids (EL, p < 0.05). The amount of DHA was doubled in EL of DHA-supplemented patients and the ratios of AA/EPA and AA/DHA dropped significantly. We speculate that the production of pro-inflammatory/non-resolving AA-derived eicosanoids might decrease in relation to anti-inflammatory/pro-resolving DHA- and EPA-derived lipid mediators. In fact, plasma concentrations of AA-derived thromboxane B2 and the capacity of blood to convert AA to the pro-inflammatory 5-lipoxygenase product 5-hydroxyeicosatetraenoic acid were significantly reduced, while levels of the DHA-derived maresin/resolvin precursors 14-/17-hydroxydocosahexaenoic acid significantly increased due to DHA supplementation. CONCLUSION: The study shows for the first time that supplemented microalgae DHA ameliorates disease activity in patients with RA along with a shift in the balance of AA- and DHA-derived lipid mediators towards an anti-inflammatory/pro-resolving state.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Ácidos Docosahexaenoicos/uso terapéutico , Microalgas , Aceites de Plantas/uso terapéutico , Aceite de Girasol/uso terapéutico , Estudios Cruzados , Método Doble Ciego , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Resultado del Tratamiento
11.
Mol Cell Biol ; 10(11): 5967-76, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2172789

RESUMEN

The transcription rate of the haptoglobin (Hp) gene is stimulated by interleukin-1 (IL-1), IL-6, and dexamethasone in rat hepatoma (H-35) cells. To identify the cis-acting regulatory elements responsive to these hormones, various lengths of 5' Hp gene-flanking regions, including the promoter, were inserted into chloramphenicol acetyltransferase gene expression vectors and transiently introduced into H-35 cells. The first 4 kb of 5' region mediated a severalfold increase in expression after treatment with IL-6 and dexamethasone. No response to IL-1 was detectable. When, however, upstream sequences were deleted to position -165 relative to the transcription start site, a significant stimulation by IL-1 was gained without appreciably affecting the IL-6 response. With the apparent removal of an inhibitory sequence, the promoter-proximal 165-bp region also displayed a severalfold enhanced response to the combination of dexamethasone, IL-1, and IL-6. The sequence from -165 to -147, termed the A-element, was found to be crucial for all hormone regulatory functions. Two copies of the A-element linked to a heterologous promoter responded to the three hormones, but to a lesser degree than in the Hp gene promoter context. The regulatory elements of the rat Hp gene were similarly active in human hepatoma cells. Optimal regulation by IL-6 in HepG2 cells was, however, independent of the A-element. The A-element functioned in these cells exclusively as an IL-1 response sequence. The results suggest that genomic sequences upstream of the rat Hp gene suppress the regulation by specific cytokines more prominently in transient expression assays than in the normal chromosomal context. Moreover, the functional comparison indicated that specific regulatory regions of the rat Hp gene do not function identically in different hepatic cell types.


Asunto(s)
Genes/efectos de los fármacos , Haptoglobinas/genética , Interleucina-1/farmacología , Interleucina-6/farmacología , Animales , Secuencia de Bases , Carcinoma Hepatocelular , Línea Celular , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Dexametasona/farmacología , Expresión Génica/efectos de los fármacos , Humanos , Cinética , Neoplasias Hepáticas , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Plásmidos , Regiones Promotoras Genéticas/efectos de los fármacos , Ratas , Proteínas Recombinantes/farmacología
12.
Cancer Res ; 61(22): 8274-83, 2001 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11719460

RESUMEN

We have used genome-wide allelotyping with 348 polymorphic autosomal markers spaced, on average, 10 cM apart to quantitate the extent of intrachromosomal instability in 59 human sporadic colorectal carcinomas. We have compared instability measured by this method with that measured by inter-(simple sequence repeat) PCR and microsatellite instability assays. Instability quantitated by fractional allelic loss rates was found to be independent of that detected by microsatellite instability analyses but was weakly associated with that measured by inter-(simple sequence repeat) PCR. A set of seven loci were identified that were most strongly associated with elevated rates of fractional allelic loss and/or inter-(simple sequence repeat) PCR instability; these seven loci were on chromosomes 3, 8, 11, 13, 14, 18, and 20. A lesser association was seen with two loci flanking p53 on chromosome 17. Coordinate loss patterns for these loci suggest that at least two separate sets of cooperating loci exist for intrachromosomal genomic instability in human colorectal cancer.


Asunto(s)
Aberraciones Cromosómicas , Neoplasias Colorrectales/genética , Pérdida de Heterocigocidad , Repeticiones de Microsatélite/genética , Alelos , Genoma Humano , Humanos , Reacción en Cadena de la Polimerasa/métodos
13.
J Invest Surg ; 29(5): 266-74, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26980291

RESUMEN

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) are frequent comorbidities in perioperative patients. However, the predictive role of the hepatokine fetuin A was not evaluated in this collective. OBJECTIVE: To study fetuin A as predictor of NAFLD/NASH in preoperative patients. METHODS: 58 subjects were included. Fetuin A was studied in patients undergoing open abdominal surgery and in a subset with acute liver failure. Blood and liver specimens were sampled. NAFLD was histologically evaluated. Liver fat was additionally analyzed by an enzymatic approach, circulating fetuin A by enzyme linked-immunosorbent assay, fetuin A mRNA by reverse-transcription PCR. RESULTS: Univariate correlation studies linked fetuin A to liver steatosis (r = 0.40, p = .029) and hepatocellular ballooning degeneration (r = 0.34, p = .026). Compared to non-NAFLD subjects fetuin A was increased in NAFLD (p = .009) and in NASH (p = .029). However, when corrected for main confounders by linear modeling, fetuin A remained related to hepatic steatosis, but not to ballooning degeneration or other NAFLD features. In support of this, biochemically analyzed liver lipids correlated with fetuin A in plasma (r = 0.34, p = .033) and with hepatic fetuin A mRNA (r = 0.54, p < .001). In addition, plasma fetuin A was related to hepatic mRNA (r = 0.32, p = .036), while circulating levels were reduced by 64% with acute liver failure (p < .001), confirming the liver as main fetuin A source. CONCLUSION: Fetuin A is suggested as noninvasive biomarker of hepatic steatosis in preoperative settings.


Asunto(s)
Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , alfa-2-Glicoproteína-HS/metabolismo , Biomarcadores/sangre , Biomarcadores/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Femenino , Humanos , Metabolismo de los Lípidos , Hígado/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Periodo Preoperatorio , ARN Mensajero/genética , ARN Mensajero/metabolismo , alfa-2-Glicoproteína-HS/genética
14.
Biochim Biophys Acta ; 1443(3): 334-42, 1998 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-9878814

RESUMEN

Our objective was to assess the reproducibility of the 60-Hz magnetic field-induced, time-dependent transcription changes of c-fos, c-jun and c-myc oncogenes in CEM-CM3 cells reported by Phillips et al. (Biochim. Biophys. Acta, 1132 (1992) 140-144). Cells were exposed to a 60-Hz magnetic field (MF) at 0.1 mT (rms), generated by a pair of Helmholtz coils energized in a reinforcing (MF) mode, or to a null magnetic field when the coils were energized in a bucking (sham) mode. After MF or sham exposure for 15, 30, 60 or 120 min, nuclei and cytoplasmic RNA were extracted. Transcription rates were measured by a nuclear run-on assay, and values were normalized against either their zero-time exposure values, or against those of the c-G3PDH (housekeeping) gene at the same time points. There was no significant difference, at P=0.05, detected between MF and either sham-exposed or control cells at any time point. Transcript levels of the oncogenes were measured by Northern analysis and normalized as above. No significant difference (P=0.05) in transcript levels between MF and either sham-exposed or control cells was detected.


Asunto(s)
Campos Electromagnéticos , Oncogenes/genética , ARN/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas Proto-Oncogénicas c-fos/genética , Proteínas Proto-Oncogénicas c-jun/genética , Proteínas Proto-Oncogénicas c-myc/genética , ARN/genética , Transcripción Genética , Células Tumorales Cultivadas/citología , Células Tumorales Cultivadas/metabolismo
15.
Exp Clin Endocrinol Diabetes ; 113(1): 8-12, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15662589

RESUMEN

The iodine supply in Germany has improved throughout the last decade, albeit with enormous differences between individuals and regions. In the Thuringian city of Jena, analyses of the iodine content of human milk have been undertaken regularly since 1982. Significantly increasing iodine concentrations in human and cow's milk have been found. Therefore, the current situation and the effectiveness of measures to prevent iodine deficiency demands re-evaluation. The iodine content of human milk from 32 lactating mothers was analysed on the 5th day (mean) postpartum and mothers' dietary iodine intake during the last two months of pregnancy was assessed by means of a food frequency questionnaire. To corroborate the assumption that the increasing iodine levels of cow's milk are one of the main reasons for the improved iodine supply, the iodine concentration of 34 cow's milk bulk-samples was also determined. Both human and cow's milk samples were analysed by the ICP-MS method. Twenty women took iodine supplements (mean daily intake = 175 microg). The average daily iodine intake of the 20 supplemented and 12 non-supplemented women was 258 microg and 116 microg, respectively. Daily iodine intake from food and beverages was significantly lower in supplemented women (83 microg/day). The average iodine content of human milk was 169 +/- 88 microg/l with a range of 33 - 348 microg/l. This content is two times higher than levels from 1994 in the same area. There was no difference in the human milk iodine content between mothers taking supplements and those who did not. Cow's milk samples showed a mean iodine concentration of 178 +/- 131 microg/l (range 48 - 661 microg/l).


Asunto(s)
Yodo/análisis , Leche Humana/química , Leche/química , Adulto , Animales , Enfermedades Carenciales/prevención & control , Suplementos Dietéticos , Femenino , Alemania , Humanos , Yodo/administración & dosificación , Yodo/deficiencia , Concentración Osmolar , Proyectos Piloto , Periodo Posparto , Embarazo , Factores de Tiempo
16.
Eur J Clin Nutr ; 59(6): 768-75, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15870821

RESUMEN

OBJECTIVE: The essential amino acid L-methionine is a potential compound in the prophylaxis of recurrent or relapsing urinary tract infection due to acidification of urine. As an intermediate of L-methionine metabolism, homocysteine is formed. The objective was to study the metabolism of L-methionine and homocysteine, and to assess whether there are differences between patients with chronic urinary tract infection and healthy control subjects. DESIGN: A randomized placebo-controlled double-blind intervention study with cross-over design. SETTING: Department of Nutritional Physiology, Institute of Nutrition in cooperation with the Department of Internal Medicine III, Friedrich Schiller University of Jena, Germany. SUBJECTS: Eight female patients with chronic urinary tract infection and 12 healthy women (controls). INTERVENTIONS: After a methionine-loading test, the volunteers received 500 mg L-methionine or a placebo three times daily for 4 weeks. MAIN OUTCOME MEASURES: Serum and urinary concentrations of methionine, homocysteine, cystathionine, cystine, serine, glycine and serum concentrations of vitamin B12, B6 and the state of folate. RESULTS: Homocysteine plasma concentrations increased from 9.4+/-2.7 micromol/l (patients) and 8.9+/-1.8 micromol/l (controls) in the placebo period to 11.2+/-4.1 micromol/l (P=0.031) and 11.0+/-2.3 micromol/l (P=0.000), respectively, during L-methionine supplementation. There were significant increases in serum methionine (53.6+/-22.0 micromol/l; P=0.003; n=20) and cystathionine (0.62+/-0.30 micromol/l; P=0.000; n=20) concentrations compared with the placebo period (33.0+/-12.0 and 0.30+/-0.10 micromol/l; n=20). Simultaneously, renal excretion of methionine and homocysteine was significantly higher during L-methionine intake. CONCLUSIONS: Despite an adequate vitamin status, the supplementation of 1500 mg of L-methionine daily significantly increases homocysteine plasma concentrations by an average of 2.0 micromol/l in patients and in control subjects. An optimal vitamin supplementation, especially with folate, might prevent such an increase.


Asunto(s)
Aminoácidos/sangre , Homocisteína/sangre , Metionina/farmacología , Infecciones Urinarias/prevención & control , Adulto , Anciano , Aminoácidos/orina , Estudios Cruzados , Suplementos Dietéticos , Método Doble Ciego , Femenino , Ácido Fólico/sangre , Homocisteína/metabolismo , Homocisteína/orina , Humanos , Metionina/sangre , Metionina/orina , Persona de Mediana Edad , Infecciones Urinarias/sangre , Infecciones Urinarias/orina , Vitamina B 12/sangre , Vitamina B 6/sangre
17.
Food Chem ; 180: 77-85, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25766804

RESUMEN

Due to their health-beneficial ingredients the consumption of nuts can contribute to a healthy diet. The composition of hazelnuts, almonds, macadamia nuts, pistachios and walnuts regarding health-promoting and potentially harmful compounds was examined before and after roasting under different time and temperature conditions. Fatty acid compositions were not affected by roasting. Malondialdehyde increased with higher roasting temperatures (17-fold in walnuts). Levels of tocopherol isomers were reduced after roasting (α-T: 38%, ß-T: 40%, γ-T: 70%) and hydrophilic antioxidant capacity decreased significantly in hazelnuts (1.4-fold), macadamia nuts (1.7-fold) and walnuts (3.7-fold). Increasing roasting temperatures supported the formation of significant amounts of acrylamide only in almonds (1220 µg kg(-1)). In general, nuts roasted at low/middle temperatures (120-160°C) exhibited best sensory properties. Therefore, desired sensory quality along with a favourable healthy nut composition may be achieved by roasting over a low to medium temperature range.


Asunto(s)
Acrilamida/metabolismo , Calor/uso terapéutico , Nueces/química , Tocoferoles/metabolismo , Antioxidantes , Ácidos Grasos
18.
Am J Clin Nutr ; 46(4): 652-8, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3499065

RESUMEN

In infants receiving intermittent high dose vitamin D prophylaxis (600,000 IU ergocalciferol per dose orally) every 3-5 mo, the serum concentrations of vitamin D metabolites, calcium (Ca), and phosphorus (P) were determined before and 2 wk after each dose. The 25-hydroxyvitamin D (OHD) concentrations increased to well above normal but the values returned to the normal range before each subsequent dose. The 24,25- and 25,26-dihydroxyvitamin D ([OH]2D) levels followed a pattern similar to that of 25-OHD, and both were closely related to the latter (r = 0.85, p less than 0.005, and r = 0.84, p less than 0.005, respectively). The 1,25-(OH)2D concentrations did not vary in a consistent pattern and remained largely within the normal range. All infants had normal Ca levels before the first dose but 14 infants (34%) later had one or both Ca values above the upper normal limit of 2.80 mmol/L (2.81-3.32 mmol/L), indicating that the vitamin D doses were excessive despite the lack of accumulative increases in serum vitamin D concentrations.


Asunto(s)
Calcio/sangre , Ergocalciferoles/administración & dosificación , Fósforo/sangre , Vitamina D/sangre , 24,25-Dihidroxivitamina D 3 , 25-Hidroxivitamina D 2 , Factores de Edad , Calcifediol/sangre , Dihidroxicolecalciferoles/sangre , Relación Dosis-Respuesta a Droga , Ergocalciferoles/análogos & derivados , Ergocalciferoles/sangre , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Raquitismo/prevención & control
19.
Shock ; 1(2): 87-93, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7538432

RESUMEN

This study assessed the hepatic acute phase response and cellular Ca2+ regulation in septic animals and in hepatoma cell lines in vitro. Sepsis was induced in male Sprague-Dawley rats by implanting in their abdominal cavities fecal pellets impregnated with live Escherichia coli and Bacteroides fragilis. 8 h after implantations, rats were treated with diltiazem (1.2 mg/kg) or superoxide dismutase (SOD) (5 x 10(3) units/kg). After 24 h, plasma acute phase proteins (APP) were determined by immunoelectrophoresis, and hepatic APP-mRNAs by Northern blot hybridization. Effects of diltiazem, verapamil, or SOD on hepatic cells were determined in rat Reuber H-35 and human HepG2 hepatoma cells. Sepsis induced a significant increase in plasma APP and their hepatic mRNAs. Diltiazem and SOD reduced the sepsis-induced elevations in plasma lactate, the febrile response and mortality. APP expression in H-35 and HepG2 cells, stimulated by interleukin 1 (IL-1), IL-6, and dexamethasone, was inhibited by diltiazem or verapamil but not SOD. The results suggest that a heightened hepatic APP response in septic animals accompanies systemic/metabolic derangements and a significant animal mortality. Because diltiazem was previously shown to prevent sepsis-related disturbances in hepatic cellular Ca2+ regulation, its mediation of decrease in APP, systemic/metabolic response, and mortality may be effected through modifications in cellular Ca2+ regulation. The data from hepatoma cells show an attenuation of the AAP can result from direct effects of a calcium blocker. However, whether the blocker primarily modifies cellular Ca2+ regulation and secondarily effects APP gene expression, or directly effects gene expression remains unknown.


Asunto(s)
Proteínas de Fase Aguda/biosíntesis , Reacción de Fase Aguda/metabolismo , Calcio/metabolismo , Diltiazem/farmacología , Infecciones por Bacterias Gramnegativas/metabolismo , Hígado/efectos de los fármacos , Peritonitis/metabolismo , Sepsis/metabolismo , Superóxido Dismutasa/farmacología , Proteínas de Fase Aguda/genética , Animales , Infecciones por Bacteroides/tratamiento farmacológico , Infecciones por Bacteroides/metabolismo , Bacteroides fragilis , Proteínas Sanguíneas/análisis , Carcinoma Hepatocelular/patología , Diltiazem/uso terapéutico , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Interleucina-1/farmacología , Interleucina-6/farmacología , Hígado/metabolismo , Neoplasias Hepáticas/patología , Masculino , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Peritonitis/tratamiento farmacológico , Ratas , Ratas Sprague-Dawley , Sepsis/tratamiento farmacológico , Superóxido Dismutasa/uso terapéutico , Células Tumorales Cultivadas , Verapamilo/farmacología , Verapamilo/uso terapéutico
20.
Radiat Res ; 151(2): 201-8, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9952305

RESUMEN

This study was designed to test the hypothesis that a 0.1-0.8-mT 60 Hz magnetic field may act as a promoter of carcinogenesis. C3H 10T1/2 mouse fibroblasts initiated with the carcinogen methylcholanthrene (INIT/10T1/2 cells) were used; in these cells, expression of the carcinogenic phenotype is suppressed indefinitely by the presence of retinyl acetate in the culture medium. After withdrawal of retinyl acetate, expression of the carcinogenic phenotype may be observed as the loss of contact inhibition. Cells grown without retinyl acetate were exposed to 0.1-0.8-mT (rms) 60 Hz magnetic fields or to sham fields. Eight days after exposure, magnetic-field and sham-exposed cells showed the same levels of incorporation of [3H]thymidine, and both had counts significantly higher than those of unexposed cells. The rate of incorporation of [3H]thymidine was very sensitive to small (0.1-0.8 degrees C) and transient (60 min) increases in incubation temperature during the first few days of withdrawal of retinyl acetate. Exposure of Jurkat (human acute T-cell lymphoma) and GH3 (rat pituitary tumor) cells to magnetic fields and sham conditions yielded similar results. INIT/10T1/2 cells cultured in the presence of retinyl acetate showed no effect of exposure conditions. Both magnetic-field and sham exposures caused a slight increase in temperature within the exposure zone in the incubator. Thus the differences between rates of incorporation of [3H]thymidine in magnetic field-exposed, sham-exposed and unexposed cells seem to be attributable at least in part to a slight elevation in temperature during exposure. Since some cells appear to be extremely sensitive to small increases in temperature, measurements of magnetic-field effects must be made and interpreted with caution.


Asunto(s)
ADN/biosíntesis , Campos Electromagnéticos , Fibroblastos/metabolismo , Animales , Células CHO/citología , Células CHO/metabolismo , Carcinógenos , División Celular/fisiología , Transformación Celular Neoplásica , Cricetinae , Fibroblastos/citología , Calor , Humanos , Células Jurkat/citología , Células Jurkat/metabolismo , Metilcolantreno , Ratones , Ratones Endogámicos C3H , Proteínas Proto-Oncogénicas c-myc/biosíntesis , Acetato de Tetradecanoilforbol , Timidina/metabolismo , Tritio
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