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1.
There was performed a comparative evaluation of the mean values of lipid metabolism parameters in youths and girls of the indigenous population (the Even), of the coming population of the north of Irkutsk province, and of the province center (the Europeoids). Gender differences in HDLP have been revealed in adolescents of the coming population, in the glutathione status and the content of liposoluble vitamins in the Even and coming adolescents and in retinol concentration in the province center adolescents. Adaptive changes in the ROS system were found in the Even girls (the higher α-tocopherol and GSH concentrations and the GSH/GSSG ratio as well as a decrease of GSSG relative to the Even youths and the coming population girls, an increase of α-tocopherol relatively to the coming population Europeoids) and youth of the coming population (the higher GSH content and the GSH/GSSG parameter relatively to the Even youths).  相似文献   

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1. Specific lipoproteins binding alpha-tocopherol but not its known metabolites have been isolated and identified from cytosol of rat intestinal mucosa and from serum. 2. A timestudy of the appearance of the orally administered alpha-[(3)H]tocopherol with these lipoproteins indicates that very-low-density lipoprotein of serum acts as a carrier of the vitamin. 3. The involvement of the mucosal lipoprotein in the absorption of the vitamin from the intestine has been inferred from observations on the amounts of alpha-tocopherol in serum of orotic acid-fed rats where release of lipoproteins from the liver to serum is completely inhibited. A considerable decrease in the association of alpha-tocopherol with serum very-low-density lipoprotein under this condition is interpreted to mean that serum lipoproteins are limiting factors for the transport of the vitamin across the intestine and that this is possibly effected by exchange of alpha-tocopherol between serum very-low-density lipoprotein and mucosal lipoprotein.  相似文献   

4.
Leucine and -ketoisocaproate (-KIC) were perfused at increasing concentrations into rat brain hippocampus by microdialysis to mimic the conditions of maple syrup urine disease. The effects of elevated leucine or -KIC on the oxidation of L-[U-14C]glutamate and L-[U-14C]glutamine in the brain were determined in the non-anesthetized rat. 14CO2 generated by the metabolic oxidation of [l4C]glutamate and [14C]glutamine in brain was measured following its diffusion into the eluant during the microdialysis. Leucine and -KIC exhibited differential effects on 14CO2 generation from radioactive glutamate or glutamine. Infusion of 0.5 mM -KIC increased [l4C]glutamate oxidation approximately 2-fold; higher concentrations of -KIC did not further stimulate [14C]glutamate oxidation. The enhanced oxidation of [14C]glutamate may be attributed to the function of -KIC as a nitrogen acceptor from [14C]glutamate yielding [14C]-ketoglutarate, an intermediate of the tricarboxylic acid cycle. [14C-]glutamine oxidation was not stimulated as much as [14C-]glutamate oxidation and only increased at 10 mM -KIC reflecting the extra metabolic step required for its oxidative metabolism. In contrast, leucine had no effect on the oxidation of either [14C]glutamate or [14C]glutamine. In maple syrup urine disease elevated -KIC may play a significant role in altered energy metabolism in brain while leucine may contribute to clinical manifestations of this disease in other ways.  相似文献   

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We investigated the significance of hydrophobic and charged residues 218–226 on the structure and functions of apoA-I and their contribution to the biogenesis of HDL. Adenovirus-mediated gene transfer of apoA-I[L218A/L219A/V221A/L222A] in apoA-I−/− mice decreased plasma cholesterol and apoA-I levels to 15% of wild-type (WT) control mice and generated pre-β- and α4-HDL particles. In apoA-I−/− × apoE−/− mice, the same mutant formed few discoidal and pre-β-HDL particles that could not be converted to mature α-HDL particles by excess LCAT. Expression of the apoA-I[E223A/K226A] mutant in apoA-I−/− mice caused lesser but discrete alterations in the HDL phenotype. The apoA-I[218–222] and apoA-I[E223A/K226A] mutants had 20% and normal capacity, respectively, to promote ABCA1-mediated cholesterol efflux. Both mutants had ∼65% of normal capacity to activate LCAT in vitro. Biophysical analyses suggested that both mutants affected in a distinct manner the structural integrity and plasticity of apoA-I that is necessary for normal functions. We conclude that the alteration of the hydrophobic 218–222 residues of apoA-I disrupts apoA-I/ABCA1 interactions and promotes the generation of defective pre-β particles that fail to mature into α-HDL subpopulations, thus resulting in low plasma apoA-I and HDL. Alterations of the charged 223, 226 residues caused milder but discrete changes in HDL phenotype.  相似文献   

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Restriction fragment polymorphisms were used to order the alpha A-crystallin locus (Crya-1) relative to other genes in mouse t-chromatin and to investigate the relatedness of alpha-A-crystallin sequences among different t-haplotypes. Analysis of DNA from t-recombinant mice mapped Crya-1 to the K end of the H-2 complex and within the distal inverted region characteristic of t-haplotypes. Hybridization with Crya-1 cDNA revealed three distinct phenotypic groups among the 17 different t-haplotypes studied. A majority (9 of 17) of the t-haplotypes were classified into a novel group (Crya-1t) characterized by restriction fragments apparently unique to t-chromosomes and therefore thought to contain alpha A-crystallin sequences descended from the original t-chromosome. A second group of t-haplotypes had restriction fragment patterns indistinguishable from those observed among many common inbred strains of mice of the Crya-1a type, and a third restriction fragment pattern, observed only in the tw121 haplotype, was indistinguishable from the fragment pattern for C3H/DiSn (Crya-1b) and several other inbred strains of mice. Thus, with respect to sequences around the Crya-1 locus, different t-haplotypes show restriction fragment polymorphisms, some of which are comparable to those found in wild-type chromosomes and provide further evidence for genetic heterogeneity in DNA from the distal region of t-haplotypes.  相似文献   

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Molecular Genetics and Genomics - A series of λ derivatives carrying tof mutations were tested for their ability to give rise to plasmid λ dv. Phages carrying tof mutations that distorted...  相似文献   

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BackgroundCopper has an important role in nervous system function, as a cofactor of many enzymes and in the synthesis of neurotransmitters. Both the dose and the chemical form of copper can determine the impact of this element on metabolism, the neurological system and the immune system.AimsThe aim of the study was to determine whether and in what form the addition of copper changes the level of amyloid beta and acetylcholinesterase level in selected rat tissues.MethodsThirty, healthy, male, albino Wistar rats aged 7 weeks were randomly divided into 3 groups. Three experimental treatments were used to evaluate the effects of different levels and sources of Cu (6.5 mg kg of diet) in the diet: Cu0 – rats fed a diet without Cu supplementation; Cusalt – rats fed a diet with CuCO3 (6.5 mg kg of diet) during two months of feeding; CuNPs - rats fed a diet with Cu nanoparticles (6.5 mg kg of diet) during two months of feeding. In blood serum and tissue homogenates there rated the indicators proving the potential neurodegenerative effect and epigenetic DNA damage induced by chemical form of copper or lack of additional copper supplementation in diet were determined. There were analysed: level of acetylcholinesterase, β-amyloid, low-density lipoprotein receptor-related protein 1, apyrimidinic endonuclease, thymidine glycosidase, alkylpurine-DNA-N-glycosylase and glycosylated acetylcholinesterase.ResultsIrrespective of the form of copper added, it was found to increase acetylcholinesterase level in the brain, spleen and liver, as well as in the blood plasma of the rats. Copper in the form of CuCO3 was found to increase acetylcholinesterase level in the kidneys. The addition of both forms of copper caused a marked increase in the plasma concentration of β-amyloid in comparison with the diet with no added Cu. The addition of both forms of copper caused a marked increase in the plasma concentration of β-amyloid in comparison with the diet with no added Cu.ConclusionsA lack of added Cu in the diet of rats reduces the concentration of amyloid-β in the blood, whereas administration of copper, in the form of either CuNPs or CuCO3, increases the level of this peptide in the blood. The use of copper in the form of CuNPs in the diet of rats does not increase the level of β-amyloid more than the use of the carbonate form of this element. The use of CuNPs or CuCO3 in the diet of rats increases acetylcholinesterase level in the brain, spleen, liver, and blood. CuNPs in the diet of rats were not found to increase acetylcholinesterase level to a greater extent than Cu+2 carbonate.  相似文献   

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The purpose of this study was to verify the concurrent validity of a bar-mounted Myotest? instrument in measuring the force and power production in the squat and bench press exercises when compared to the gold standard of a computerized linear transducer and force platform system. Fifty-four men (bench press: 39-171 kg; squat: 75-221 kg) and 43 women (bench press: 18-80 kg; squat: 30-115 kg) (age range 18-30 years) performed a 1 repetition maximum (1RM) strength test in bench press and squat exercises. Power testing consisted of the jump squat and the bench throw at 30% of each subject's 1RM. During each measurement, both the Myotest? instrument and the Celesco linear transducer of the directly interfaced BMS system (Ballistic Measurement System [BMS] Innervations Inc, Fitness Technology force plate, Skye, South Australia, Australia) were mounted to the weight bar. A strong, positive correlation (r) between the Myotest and BMS systems and a high correlation of determination (R2) was demonstrated for bench throw force (r = 0.95, p < 0.05) (R2 = 0.92); bench throw power (r = 0.96, p < 0.05) (R2 = 0.93); squat jump force (r = 0.98, p < 0.05) (R2 = 0.97); and squat jump power (r = 0.91, p < 0.05) (R2 = 0.82). In conclusion, when fixed on the bar in the vertical axis, the Myotest is a valid field instrument for measuring force and power in commonly used exercise movements.  相似文献   

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This meeting of the Committee on the History of Science and Epistemology takes place as we celebrate the 250th anniversary of the creation of the world's first veterinary schools, a major event among all those that, in the wake of the Physiocrat movement initiated by Quesnay and DuPont de Nemours, shaped the modernisation of agriculture in France during the 18th century. Henri-Léonard Bertin (1720-1792) was the impetus to the restructuring process. He was well aware that farming should not remain an activity that solely provides a livelihood for the population, but that it needed to be modernised, i.e. it should produce more, and better. His view was that agriculture could become a great source of riches for France and therefore, a true economic and even political force. He used the various official positions he occupied during that period (Intendant of Lyon (1754-1757), Controller General of Finances (1759-1763), Minister-Secretary of State for Agriculture (1763-1780) to initiate a number of reforms that brought about the modernisation of the kingdom's agricultural world.  相似文献   

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Summary For unexplained reasons, nerve growth factor (NGF) exists in very high concentrations in the submandibular gland of the mouse. The NGF in the gland, called 7S-NGF, is a non-covalent complex of three protein subunits, named -, - and -NGF. All the known biological activity resides in the -NGF subunit, and previous studies have shown that -NGF is present in much greater concentrations in the male submandibular gland than in the female gland. The higher concentration in the male is due to the fact that -NGF is synthesized in the granular tubule cells of the submandibular gland. These cells are much more numerous in the male gland.In contrast to -NGF, neither the concentrations of and subunits nor their cellular localization in the mouse submandibular gland have been established. In this study, radioimmunoassays specific for . and subunits determined that both are present in much higher concentrations in the male gland. Immunocytochemical work localized both subunits in the granular tubule cell in the male and female submandibular gland. This indicates that all the components of 7S-NGF exist in a single cell type in the gland and suggests that 7S-NGF can be formed within this cell and secreted as a complex into the saliva.  相似文献   

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Summary The localization and sites of synthesis of -fetoprotein in chick embryos throughout development have been investigated using the combined techniques of immunofluorescence microscopy and tissue culture in the presence of radiolabelled amino acids, followed by immunoautoradiographic analysis.Alpha-fetoprotein is present in a range of embryonic tissues and especially concentrated in the yolk sac, liver and connective tissue. Analysis of culture fluids revealed that the yolk sac is the major site of -fetoprotein synthesis with smaller, but significant quantities being produced by the liver.These results are discussed in relation to mammalian -fetoprotein, and the merits of the chick embryo for studies on the biological function of AFP are considered.Supported by an award from the Science Research Council, to whom grateful acknowledgement is made  相似文献   

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Objective

We estimated the extent to which Canadian expectant parents would seek medical care in a febrile neonate (age 30 days or less). We also evaluated expectant parents’ knowledge of signs and symptoms of fever in a neonate, and explored the actions Canadian expectant parents would take to optimize the health of their child.

Methods

We conducted a cross-sectional survey of a sample of expectant parents from a large urban center in Canada. We recruited participants from waiting rooms in an obstetrical ultrasound clinic located in an urban tertiary care hospital in Montreal, Canada. We asked participants nine questions about fever in neonates including if, and how, they would seek care for their neonate if they suspected he/she were febrile.

Results

Among the 355 respondents, (response rate 87%) we found that 75% of parents reported that they would take their febrile neonate for immediate medical assessment, with nearly one fifth of the sample reporting that they would not seek medical care. We found no significant associations between the choice to seek medical care and expectant parents socio-demographic characteristics.

Conclusions

Despite universal access to high quality health care in Canada, our study highlights concerning gaps in the knowledge of the care of the febrile infant in one fifth of expectant parents. Physicians and health providers should strive to provide early education to expectant parents about how to recognize signs of fever in the neonate and how best to seek medical care. This may improve neonatal health outcomes in Canada.  相似文献   

15.
A genetic epidemiological study of hereditary diseases of the nervous system (HDNS) was conducted in the cities of Volgograd and Volzhsky for the first time. In total, 1 323 500 individuals were examined including the populations of Volgograd and Volzhsky (1 012 800 and 310 700 persons, respectively). The prevalence of neurological diseases with autosomal dominant (AD), autosomal recessive (AR), and X-linked recessive inheritance was estimated. These data were compared with the estimates previously obtained for different population of the Russian Federation. A decrease was found in general HDNS load in Volgograd and Volzhsky. The compared populations were shown to differ in a contribution of AD, AR, and X-linked recessive diseases into the HDNS load formation. The possible effect of population dynamics factors on the HDNS load structure is discussed.  相似文献   

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Opisthorchis viverrini infection induces inflammation-mediated oxidative stress and liver injury, which may alter α-tocopherol and lipid metabolism. We investigated plasma α-tocopherol and lipid profiles in hamsters infected with O. viverrini. Levels of α-tocopherol, cholesterol, and low-density lipoprotein increased in the acute phase of infection. In the chronic phase, α-tocopherol decreased, while triglyceride and very low-density lipoprotein increased. Notably, high-density lipoprotein decreased both in the acute and chronic phases. In the liver, cholesteryl oleate, triolein, and oleic acid decreased in the acute phase, and increased in the chronic phase. Such chronological changes were negatively correlated with the plasma α-tocopherol level. The expression of α-tocopherol-related molecules, ATP-binding cassette transporter A1 (ABCA1) and α-tocopherol transfer protein, increased throughout the experiment. These results suggest that O. viverrini infection profoundly affects on lipid and α-tocopherol metabolism in due course of infection.  相似文献   

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Summary The role of iodine in the formation of cold follicles (not labeled on autoradiograms after radioiodine administration) was analysed in ICR female mice during aging and involution of thyroid hyperplasia, by use of light and electron microscopy and by comparing autoradiographic and analytical ion-microscopic images for the same follicle in serial sections. The proportion of cold and partly cold (displaying a patchy or ring labeling pattern on autoradiograms) follicles increased significantly during aging. This increase was more pronounced in old mice fed an iodine-rich diet as compared to mice fed a moderate iodine diet. Similarly, during goiter involution produced by refeeding iodine, the follicular heterogeneity of iodine metabolism was more accentuated with a high dose of iodine, regardless of the age of the mice. The follicular lumina of hot and cold follicles had the same concentration of stable iodine, as shown by analytical ion microscopy, and the cells of both types of follicles formed colloid droplets in response to TSH. Furthermore, when a goitrogenic treatment was induced in aged mice, some cold follicles persisted after 8 days, but all follicles resumed hot after 16 days. By analytical ion microscopy, 127iodine was also found inside thyroid cells of old mice, but the cytoplasmic patches of 127iodine were not labeled with 125iodine. They corresponded to lipofuscin pigments and secondary lysosomes, as observed in serial sections at the electron-microscopic level. This intracellular stable iodine could constitute a slow turnover compartment not used for hormone synthesis.Portions of this work were presented at the 15th and 17th Annual Meetings of the European Thyroid Association (Stockholm 1986; Montpellier 1988). This work was supported in part by the Association de la Recherche sur le Cancer (ARC) and a cooperative programme Communauté Française de Belgique-France  相似文献   

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Although a relationship between depression and cardiovascular events has been suggested, past study results regarding the risk of stroke in relation to depression by subgroups are ambiguous. The aim of this study was to investigate the influence of depressive symptoms on risk of incident ischemic stroke in elderly according to age and sex. This prospective cohort study followed up 3852 subjects older than 55 years. Baseline depressive symptoms were defined by a score ≥5 on the Geriatric Depression Scale or antidepressant intake. The outcome measure was incident ischemic stroke within 6 years of follow-up. Multivariate Cox-proportional hazard models as well as cumulative survival analyses were computed. A total of 156 ischemic strokes occurred during the study period (24 strokes in the age-group<65 years and 132 strokes in the age-group≥65 years). The distribution of strokes in sex-subgroups was 4.5% in men and 3.7% in women. The multivariate analysis showed an elevated stroke risk (Hazard Ratio (HR): 2.84, 95% CI 1.11–7.29, p = 0.030) in subjects from 55 to 64 years with depressive symptoms at baseline but not in subjects older than 65 years. In the multivariate analysis according to sex the risk was increased in women (HR: 1.62, 95% CI 1.02–2.57, P = 0.043) but not in men. The Cox-regression model for interaction showed a significant interaction between age and sex (HR: 3.24, 95% CI 1.21–8.69, P = 0.020). This study corroborates that depressive symptoms pose an important risk for ischemic stroke, which is particularly remarkable in women and patients younger than 65 years.  相似文献   

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Summary The presence of dopamine--hydroxylase (DBH) and phenylethanol-amine-N-methyltransferase (PNMT) immunoreactivity in specific neurones of the snail Helix aspersa has been demonstrated. In addition, high performance liquid chromatography and electrochemical detection have revealed the presence of noradrenaline and adrenaline in the snail central nervous system, although the major catecholamine is dopamine. These results suggest that adrenaline, and perhaps noradrenaline, have transmitter or modulatory functions in the snail nervous system.  相似文献   

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