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1.
Hypertriglyceridemia induced by short-term lipid infusions causes redistribution of neutral lipid components between endogenous lipoproteins and emulsion particles. To determine whether such redistribution occurs over a long-term infusion period and affects lipoprotein pattern, we studied seven patients with inflammatory bowel disease who received cyclic home parenteral nutrition for two consecutive periods of 3 months with two different lipid emulsions. During each period, they received in random order either an emulsion composed exclusively of soy-derived long-chain triglycerides (LCTs) or another emulsion containing an equal weight:weight mixture of long- and medium-chain triglycerides (MCTs/LCTs). Both emulsions contained 20 triglycerides (TGs) and 1.2 phospholipids. Lipids provided 50 of nonprotein energy. Blood samples were taken once a week, 1 hour before the end of infusion (during) and again after a 6- to 8-h lipid-free interval (baseline). During infusion, there was a moderate increase of plasma TGs and phospholipids and a slight decrease of plasma esterified cholesterol (CE) and free cholesterol. Most of the plasma TGs increase occurred in the very-low-density lipoprotein fraction (containing both emulsion particles and the endogenous very-low-density lipoprotein), but there was also an increase of TGs content in low-density lipoprotein (LDL) and high-density lipoprotein (HDL) that was more pronounced with MCTs/LCTs. Acquisition by exogenous particles of CE transferred from LDL and HDL was significant for the LCT emulsion only. Although no change was observed in plasma lipid concentration of baseline samples during 3 months of home parenteral nutrition, some modifications were observed in the composition of lipoprotein fractions demonstrating a redistribution of lipid components.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

2.
In 49 prematures (25 infected and 24 healthy) serum cholesterol and triglycerides concentrations, value of alpha, pre-beta and beta serum lipoproteins (by electrophoresis) and activity of AspAt, AlAt and GGTP were estimated. It was stated, that the mean serum cholesterol concentration at the beginning of infection was significantly lower than in healthy babies, but in 2-3 week of disease the mean value of this parameter was significantly higher than in first week of life. Mean value of alpha lipoprotein was significantly lower, mean value of pre-beta and beta lipoproteins were higher in sick prematures than in control. In septic prematures positive correlation between the high serum cholesterol concentration and activity of GGTP and AspAt was found. In 30% of all septic neonates hepatitis and in 65% of dead infected prematures structural damage of liver were noted.  相似文献   

3.
We have demonstrated organ damage after long-term administration of lipid-based parenteral nutrition, possibly initiated by intravascular pooling of lipid and phagocytes, in both rats and pigs. To evaluate whether accumulation of lipid could simply be caused by mechanical filtration, a comparative study of three separate capillary beds was performed. Rats were given lipid emulsion (n = 5) or isotonic saline (n = 4) through central venous catheters for 3 weeks. Using both light and electron microscopy, lipid accumulation and structural changes in the rat myocard were compared to those in the lung and liver. The study provides evidence that within myocardial capillaries both peripheral blood monocytes and endothelial cells performed phagocytosis of lipid droplets following administration of lipid emulsion, but no large-scale intravascular pooling of lipid resulted. Morphometry of the myocard detected no lipid increase in the myocytes from the rats given lipid emulsion compared with controls and in neither were there any stigmata of vasculitis or myocardial damage, in contrast to the lung and liver, where intravascular pooling of lipid and phagocytes was seen. This indicates that phagocytosis was an important mechanism involved in entrapment and elimination of lipid.  相似文献   

4.
The experiments on mice of line SHR have shown that in animals, delivered by Cesarean section I hour following intrauterine injection of 40 mg/Kg of DMBA in mothers (a period of maximum concentration of the carcinogen in the tissues of foetuses) and sacrificed one year later, carcinogenesis proceeded much more intensively than in mice, which after transplacental DMBA exposure continued their intrauterine development for 6 hours longer, i.e. till complete disintegration of DMBA. An enhancement of the transplacental carcinogenic effect was manifested in a reliable increase of the total frequency of the appearance of different neoplasms, in more frequent development of lung, ovary and mammary tumors, and also in the appearance of malignant lung tumors-adenocarcinomas. A considerable enhancement of the transplacental blastomogenic effect in these mice was due to exclusion of the detoxication function of the maternal organism.  相似文献   

5.
6.
In order to evaluate the role of human follicular fluid (HFF) on the fertilizing capacity of spermatozoa, we studied the effect of HFF on the lipid composition and on the movement characteristics of human spermatozoa. Spermatozoa (spz) from normospermic patients were prepared with a discontinuous Percoll gradient and incubated in Ménézo B2 medium with or without a supplement of 20% HFF (HFF-Percoll spz and B2-Percoll spz respectively) for 2 and 24 h. After 2 h HFF incubation, percentage progressive motility, straight line velocity (VSL), and amplitude of lateral head displacement (ALH) were improved in HFF-Percoll spz as compared to B2-Percoll spz (P < or = 0.05). After a longer incubation period (24 h), lipid changes appeared in HFF-Percoll spz with lower levels of cholesterol (P = 0.02) and phospholipids (P = 0.05). No modification of the cholesterol/phospholipid ratio after 2 and 24 h of incubation in either B2-Percoll spz or HFF-Percoll spz was observed. Such decreases in lipid content of HFF-Percoll spz may be factors which could be taken into account as constituting part of membrane modifications during the capacitation process.  相似文献   

7.
8.
Development of atopic disease was prospectively studied in 148 children from birth to the age of 18 months and related to serum levels of IgG anti-IgE antibody. Children with a dual heredity of allergy, but remaining healthy, had significantly higher IgG anti-IgE levels at birth than children with a similar predisposition to allergy, who became allergic. Children with increased allergy risk, defined by elevated IgE levels at birth (> = 0.53 kU/l) and with probable allergy symptoms had also significantly higher IgG anti-IgE levels at birth than children of the same risk group, developing definite allergy. Independent of allergy risk, there was a significantly lower prevalence of atopic disease in children with cord serum levels of IgG anti-IgE above 350 AU/l than in children with lower levels. Additionally, we showed that the allergy predictive capacity of IgE levels in cord serum was slightly improved in specificity, sensitivity and efficiency by including not only the family history of allergy, but also cord serum levels of IgG anti-IgE. Our results thus raise the possibility that high levels of IgG anti-IgE protect children of increased allergy risk from early development of atopic disease and reduce the severity of symptoms.  相似文献   

9.
Postprandial lipid profiles and release of insulin (INS), intact proinsulin (PI), and 32-33 split proinsulin (SPI) in response to a mixed meal with a high fat content were determined over a 12 h period in non-obese control subjects (n = 10) and non-insulin-dependent (Type 2) diabetic (NIDDM) patients with normotriglyceridaemia (NTG; n = 11) and hypertriglyceridaemia (HTG; n = 10), by calculation of the 'areas under the curves' (AUC). The postprandial triglyceride-AUC was significantly greater in HTG-NIDDM patients (p < 0.05) than in NTG-NIDDM or control subjects. Chylomicron clearance was impaired only in HTG-NIDDM patients (p < 0.05). Chylomicron-remnant clearance was impaired in both groups of NIDDM patients (p < 0.05). The postprandial suppression of plasma non-esterified fatty acid (NEFA) content was impaired in HTG-NIDDM patients (p < 0.05). The postprandial INS-, PI- and SPI-AUCS were significantly greater than in the control subjects (p < 0.05). In NIDDM, triglyceride-AUC correlated significantly with PI and SPI release (triglyceride-AUC vs PI, p < 0.05; triglyceride-AUC vs SPI, p < 0.01). Chylomicron AUC was unrelated to the fasting plasma INS, PI or SPI content, unlike chylomicron-remnant-AUC (Chylomicron-remnant-AUC vs INS, p = NS; chylomicron-remnant-AUC vs PI, p < 0.01; chylomicron-remnant-AUC vs SPI, p < 0.01). The NEFA response was associated with fasting plasma SPI content (NEFA-AUC vs SPI, p < 0.05). Postprandial chylomicron AUC was not related to the overall secretion of INS, PI or SPI. However, triglyceride-, chylomicron-remnant- and NEFA-AUCs were all associated positively with the release of PI and SPI (p < 0.05). In multivariate analyses, chylomicron-remnant clearance had the major relationship with the release of insulin precursors, accounting for 23% of the variability (p < 0.01). Inclusion of overall response of free fatty acids improved the model, with both parameters together accounting for 30% of the variability (p < 0.01). The output of the beta-cell over the postprandial period differed between the NIDDM patients and the control subjects in that when glycaemic stimulation was moderate, the proportion of insulin-like molecules as a percentage of the total output was greater than in control subjects but this was not the situation when glycaemia was greatest. We conclude that abnormal postprandial lipaemia in NIDDM is associated with beta-cell output, possibly mediated by the availability of free fatty acids.  相似文献   

10.
A comparative analysis of the reactivity of nickel and its alloy with rhenium during their direct current polarization in sulfuric acid solutions (50–150 g/L, 25–60°C) is carried out. The regions of anodic potentials of their active dissolution and passivation are determined on the basis of the analysis results. The chemical compositions of the passivation films of electrode polarization are determined by X-ray photoelectron spectroscopy. The mechanism of film formation is established. The influence of the depolarizing ability of rhenium in the alloy composition on the depassivation of the alloy is revealed and evaluated.  相似文献   

11.
The immediate effect on the pulmonary circulation of reoxygenation with either room air or 100% O2 was studied in newborn piglets. Hypoxemia was induced by ventilation with 8% O2 until base excess was <-20 mmol/L or mean arterial blood pressure was <20 mm Hg. Reoxygenation was performed with either room air (n = 9) or 100% O2 (n = 9). Mean pulmonary artery pressure increased during hypoxemia (p = 0.012). After 5 min of reoxygenation, pulmonary artery pressure increased further from 24 +/- 2 mm Hg at the end of hypoxemia to 35 +/- 3 mm Hg (p = 0.0077 versus baseline) in the room air group and from 27 +/- 3 mm Hg at the end of hypoxemia to 30 +/- 2 mm Hg (p = 0.011 versus baseline) in the O2 group (NS between groups). Pulmonary vascular resistance index increased (p = 0.0005) during hypoxemia. During early reoxygenation pulmonary vascular resistance index decreased rapidly to values comparable to baseline within 5 min of reoxygenation in both groups (NS between groups). Plasma endothelin-1 (ET-1) decreased during hypoxemia from 1.5 +/- 0.1 ng/L at baseline to 1.2 +/- 0.1 ng/L at the end of hypoxemia (p = 0.003). After 30 min of reoxygenation plasma ET-1 increased to 1.8 +/- 0.3 and 1.5 +/- 0.2 ng/L in the room air and O2 groups, respectively (p = 0.0077 in each group versus end hypoxemia; NS between groups). We conclude that hypoxemic pulmonary hypertension and plasma ET-1 normalizes as quickly when reoxygenation is performed with room air as with 100% O2 in this hypoxia model with newborn piglets.  相似文献   

12.
Calcipotriol and corticosteroids, two therapy modalities frequently prescribed in the treatment of psoriasis, are often used in combination. The aim of the present study was to determine whether the cell biological response pattern of concurrent use of calcipotriol and corticosteroids is different from calcipotriol monotherapy. Forty patients with chronic plaque psoriasis were divided at random in four parallel groups and treated for 8 weeks with: (1) calcipotriol cream (50 micrograms/g once daily); (2) calcipotriol cream twice daily; (3) calcipotriol and clobetasone 17-butyrate (0.5 mg/g) creams; and (4) calcipotriol and betamethasone 17-valerate (1 mg/g) creams. Before and after treatment keratotome biopsies were taken and single cell suspensions prepared for flow cytometric analysis. Flow cytometric multiparameter quantification of markers for proliferation (TO-PRO-3), differentiation (antikeratin 10) and inflammation (antivimentin) was used to evaluate all four therapy modalities. A statistically significant decrease of the percentage of basal cells in S- and G2M-phase (proliferation) was obtained with all therapy modalities, except for calcipotriol monotherapy applied once daily. A significant reduction of the number of vimentin-positive cells (non-keratinocytes) was observed following combined treatment with calcipotriol and clobetasone butyrate. In contrast, monotherapy with calcipotriol had virtually no effect on the number of vimentin-positive cells. It can be concluded that: (i) calcipotriol monotherapy, applied once daily was less antiproliferative compared with twice daily applications of calcipotriol or the combined treatment with corticosteroids and that (ii) the combination of calcipotriol and corticosteroids proved to have a marked effect on the percentage of non-keratinocytes, in contrast to the modest effect of calcipotriol.  相似文献   

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