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71.
M. Flesch A. Sachinidis Y. D. Ko K. Kraft H. Vetter 《Journal of molecular medicine (Berlin, Germany)》1994,72(12):944-950
In recent years there have been many studies demonstrating a correlation between increased arterial blood pressure and altered lipid profiles, and there has been an especially positive correlation between high cholesterol levels and blood pressure. There are differences between the various reports that are important. In our study the lipid distribution in 105 hypertensive patients with mild or moderate arterial hypertension according to WHO criteria without clinically or ultrasonographically apparent atherosclerosis was compared to the lipid distribution in 65 age-matched healthy persons. On the epidemiological level a significant, positive association was found between LDL serum levels (P 0.001), Apo B serum levels (P 0.001), serum triglyceride levels (P 0.05) and VLDL serum levels (P 0.01) and arterial hypertension. However, in contrast to recent reports, no significant difference was found between total serum cholesterol levels in normotensives and hypertensives, and there was no difference in HDL serum levels. No evidence could be found for a significant increase in lipoprotein (a) serum levels in hypertensives.Abbreviations LDL
low density lipoprotein
- VLDL
very low density lipoprotein
- HDL
high density lipoprotein
- Apo B 100
apolipoprotein B 100
- Apo A I
apolipoprotein A I
Correspondence to: H. Vetter 相似文献
72.
M. A. Christmass B. Dawson C. Goodman P. G. Arthur 《Acta physiologica (Oxford, England)》2001,172(1):39-52
The role of work period duration as the principal factor influencing carbohydrate metabolism during intermittent exercise has been investigated. Fuel oxidation rates and muscle glycogen and free carnitine content were compared between two protocols of sustained intermittent intense exercise with identical treadmill speed and total work duration. In the first experiment subjects (n=6) completed 40 min of intermittent treadmill running involving a work : recovery cycle of 6 : 9 s or 24 : 36 s on separate days. With 24 : 36 s exercise a higher rate of carbohydrate oxidation approached significance (P=0.057), whilst fat oxidation rate was lower (P ≤ 0.01) and plasma lactate concentration higher (P ≤ 0.01). Muscle glycogen was lower post‐exercise with 24 : 36 s (P ≤ 0.05). Muscle free carnitine decreased (P ≤ 0.05), but there was no difference between protocols. In the second experiment a separate group of subjects (n=5) repeated the intermittent exercise protocols with the addition of a 10‐min bout of intense exercise, followed by 43 ± 5 min passive recovery, prior to sustained (40 min) intermittent exercise. For this experiment the difference in fuel use observed previously between 6 : 9 s and 24 : 36 s was abolished. Carbohydrate and fat oxidation, plasma lactate and muscle glycogen levels were similar in 6 : 9 s and 24 : 36 s. When compared with the first experiment, this result was because of reduced carbohydrate oxidation in 24 : 36 s (P ≤ 0.05). There was no difference, and no change, in muscle free carnitine between protocols. A 10‐min bout of intense exercise, followed by 43 ± 5 min of passive recovery, substantially modifies fuel use during subsequent intermittent intense exercise. 相似文献
73.
Effects of social factors on adrenal weight and related physiology of Macaca fascicularis 总被引:1,自引:0,他引:1
Increased adrenal cortical activity and hypertrophy of adrenal glands associated with defeat and social subordination have been reported frequently in small mammals; these adrenal changes have been linked to impairments in immune response, glucose metabolism and reproductive performance. Similar studies in primates have produced variable results. The current study was undertaken to illuminate the effects of social status on the adrenal gland and to examine concurrent effects of social variables on other physiological systems in Macaca fascicularis, in an initial exploration of the hypothesis that high and low social status have different physiological consequences. Sixty adult male M. fascicularis were housed in social groups of n = 5, under either stable or unstable social conditions. It was found that subordinate animals had heavier adrenal glands and somewhat higher plasma glucose concentrations than dominants. In contrast, dominants had higher blood pressure and worsened atherosclerosis, under some conditions, than subordinates. These data appear to offer preliminary support for Henry and Stephen's hypothesis of differential arousal of dominant and subordinate animals. 相似文献
74.
A mathematical model is proposed to describe the intracellularCa
2+ (Ca
i) transient and electrical activity of vascular endothelial cells (VEC) elicited by fluid shear stress (τ). The intracellularCa
2+ store of the model VEC is comprised of aCa
i-sensitive (sc) and an inositol (1,4,5)-trisphosphate (IP
3)-sensitive compartment (dc). The dc [Ca
2+] is refilled by the sc whose [Ca
2+] is the same as extracellular [Ca
2+].IP
3 produced by the τ-deformed mechanoreceptors discharges the dcCa
2+ into the cytosol. The increase of cytosolic[Ca
2+] inducesCa
2+ release (CICR) from the sc. The raisedCa
i activates aCa
i-activatedK
+ current (I
K, Ca) and inhibitsIP
3 production. The cell membrane potential is determined byI
K, Ca, voltage-dependentNa
+ andK
+ currents. Steady τ>0.1 dyne/cm2 elicits aCa
i varies sigmoidally withLog
10(τ) with a maximal peakCa
i of 150 nM at τ=4 dynes/cm2. Step increases of τ fail to elicit aCa
2+ response in cells previously stimulated by a lower shear. TheCa
2+ response gradually decreases with repetitive τ stimuli. Pulsatile shear elicits two to three times higherCa
i and hyperpolarizes the cell more than steady shear of the same magnitude. The simulatedCa
2+ responses to τ are quantitatively and qualitatively similar to those observed in cultured VEC. The model provides a possible
explanation of why the vasodilating stimulus is greater for pulsatile flow than for nonpulsatile flow. 相似文献
75.
The metabolism of D-galactose is a major feature of red-algal physiology. We have cloned and sequenced a gene from the red
alga Gracilaria gracilis that encodes a key enzyme of D-galactose metabolism, galactose-1-phosphate uridylyltransferase (GALT). This gene, designated
GgGALT1, is apparently devoid of introns. A potential TATA box, four potential CAAT boxes, and a repeated sequence occur in the 5′-flanking
region. The predicted 369-aa peptide shares significant sequence similarity with GALTs from other organisms (human, 47%; Saccharomyces cerevisiae, 49%; Solanum tuberosum, 49%). Southern-hybridization analysis reveals two related, but apparently not identical, GALT genes in the nuclear genome
of G. gracilis. Sequence analysis indicates that the GgGALT1 enzyme lacks a rubredoxin “knuckle” motif, which in bacterial and fungal GALTs
is involved in binding zinc. An open reading frame encoding a potential peptidyl tRNA hydrolase occurs 179 bp downstream from
the GgGALT1 gene.
Received: 6 April / 2 June 1998 相似文献
76.
Department of Biology, Grodno Medical Institute. Department of Pathological Anatomy, A. V. Vishnevskii Institute of Surgery, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR D. S. Sarkisow.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 3, pp. 357–360, March, 1989. 相似文献
77.
Whitman SA Wacker MJ Richmond SR Godard MP 《Pflügers Archiv : European journal of physiology》2005,450(6):437-446
The primary mechanism that contributes to decreasing skeletal muscle strength and size with healthy aging is not presently known. This study examined the contribution of the ubiquitin–proteasome pathway and apoptosis to skeletal muscle wasting in older adults (n = 21; mean age = 72.76 ± 8.31 years) and young controls (n = 21; mean age = 21.48 ± 2.93 years). Subjects underwent a percutaneous muscle biopsy of the vastus lateralis to determine: (1) ubiquitin ligase gene expression (MAFbx and MuRF1); (2) frequency of apoptosis; and (3) individual fiber type and cross-sectional area. In addition, a whole muscle strength test was also performed. A one-way ANOVA revealed significant increases in the number of positive TUNEL cells in older adults (87%; p < 0.05), although no significant increase in caspase-3/7 activity was detected. Additionally, ubiquitin ligase gene expression, individual muscle fiber type and CSA were not different between old and young subjects. Muscle strength was also significantly lower in old compared to young subjects (p < 0.05). In conclusion, this study indicates a preferential role for apoptosis contributing to decreases in muscle function with age. 相似文献
78.
Lung preservation solution substrate composition affects rat lung oxidative metabolism during hypothermic storage 总被引:1,自引:0,他引:1
Peltz M Hamilton TT He TT Adams GA Koshy S Burgess SC Chao RY Jessen ME Meyer DM 《Respiratory physiology & neurobiology》2005,148(3):2771-283
Lungs harvested for transplantation utilize oxygen after procurement. We investigated the effects of storage solution substrate composition on pulmonary oxidative metabolism and energetics during the preservation interval. Rat lungs were harvested and stored at 10 degrees C in low-potassium dextran (LPD) solution. Groups of lungs were preserved with preservation solution containing 5mM carbon-13 ((13)C) labeled glucose or increasing concentrations of (13)C labeled pyruvate. Additional groups of rat lungs were studied with dichloroacetate (DCA) added to the pyruvate-modified preservation solutions. Oxidative metabolism (measured by (13)C-enrichment of glutamate) and adenine nucleotide levels were quantified. Increasing preservation solution pyruvate concentration augmented glutamate (13)C-enrichment up to a concentration of 32mM pyruvate. DCA further stimulated oxidative metabolism only at lower concentrations of pyruvate (4 and 8mM). ATP and ADP were not different among groups, but AMP levels were higher in the glucose group. These data suggest that altering the substrate composition of the preservation solution influences lung metabolism during allograft preservation for transplantation. 相似文献
79.
Under the condition of obvious iron-overload, there is a zonal hernoeiderin (iron) deposition in hepatic lobules. The deposition is heavtest in the periporfal (zone 1) and lightest in the perivenws (zone 3) hepatocytes. However, the mechanism for this pattern of iron deposition is obscure. Hepatic tissues from control, iron-deficlent or ironoverloaded Wistar rats me used to study its pathogenesis. iron-deficiency was Induced by a low Iron regimen. Ironoverload was produced by repeated intraperitoneal injections of ferric nitrilotriace-We (Fe3+ -NTA) for 1–4 months. Liver tissues of the rats were lmmunohistochemically and histochemically stained for tmnaferrin receptor (TfR), transferrin (Tf), ferritin (Ft), and iron. The staining intensity of TfR, Tf and Ft increased in hepatocytes of iron-deflctent rats and decreased in that of the iromverloaded in comparison with the control rats. TfR atalning was strong in zone 1, with gradual transition into weak staining in zone 3 hepatocytes of the rat liver. TfR located primarily on the hepatocyte membrane. Tf had both membranous and cytoplasmic distribution. Many hepatocytes in group B had strong cytoplasmic Tf staining. Conversely, only a few hepatocytes had weakly stained cytoplasmic Tf in group C. Hepatocytes and Kupffer cells were Ft positive in control rats. Ft was distributed only in the cytoplasm. The staining intensity of Ft was stronger in zone 3 than in zone 1 hepatocytes of iron-deficient rats. In iron-overloaded rats, the iron deposition was severe in zone 1 and mild in zone 3 hepatocytes. These findings suggest that uptake of iron into hepatocytes in vivo is regulated and mediated by TfR and Tf. Gradient TfR distribution from zone 1 to 3 hepatocytes and active TfR-Tf mediated iron uptake resuited in the zonal iron deposition in the hepatic lobule of iron-overloaded rats. 相似文献
80.
H. Denz B. Orth G. Weiss R. Herrmann P. Huber H. Wachter D. Fuchs 《Journal of molecular medicine (Berlin, Germany)》1993,71(1):37-41
Summary Weight loss is the main symptom of so-called tumor cachexia. The pathogenetic mechanisms underlying cachexia are poorly understood; however, it appears that enhanced formation of cytokines such as interferon- and tumor necrosis factor- are involved. In 94 patients suffering from hematological neoplasias we compared body weight changes with serum neopterin, tryptophan, and kynurenine. Biochemical changes, the formation of neopterin, the degradation of tryptophan are closely related to interferon- activity. The majority of our patients had increased neopterin and decreased tryptophan concentrations. Weight loss was seen particularly in patients with higher neopterin and lower tryptophan values. An association between higher neopterin levels and greater weight loss was apparent at study entry and during the follow-up of patients. Our data support the concept that weight loss is closely linked to endogenous interferon- activity.Abbreviations NHL
non-Hodgkin's lymphoma
- HD
Hodgkin's disease
- MM
multiple myeloma
- MGUS
monoclonal gammopathy of unknown significance
- IFN-
interferon-
- TNF-
tumor necrosis factor- 相似文献