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L Schreier

Publications and source records attributed to L Schreier.

16 recordsLinked to original sources
PubMed2006

Metabolic syndrome throughout the menopausal transition: influence of age and menopausal status.

OBJECTIVE: To assess the relationship between the main components of both the metabolic syndrome and insulin resistance and menopausal status in the menopausal transition. METHODS: A total of 124 healthy women were divided into four groups according to their menstrual status: the first group consisted of 35 women in menopausal transition with menstrual bleeding (MTM) and with cycles between 35 and 80 days; the second group was composed of 29 women in menopausal transition with 3-6 months of amenorrhea (MTA). The third group consisted of 31 postmenopausal women (PostM) and the fourth group of 29 premenopausal women (PreM) with regular cycles. The metabolic syndrome was evaluated following the ATP III criteria. Evaluation of insulin resistance was made through the HOMA, QUICKI and McAuley indices and the triglycerides/high density lipoprotein (HDL) cholesterol ratio. RESULTS: The triglycerides/HDL cholesterol ratio increased in MTM, MTA and PostM women in comparison with PreM women. A slight decrease in the QUIKI index (p = 0.06) and a decrease in the McAuley index (p < 0.001) were observed in MTM, MTA and PostM women in comparison to PreM women. The relative frequencies of metabolic syndrome in the four groups were: PreM, 0%; MTM, 20%; MTA, 21%; and PostM, 22% (p = 0.0001). The most frequent markers of the metabolic syndrome were increased waist circumference, low HDL cholesterol levels and hypertension. Linear regression between menopausal status and metabolic syndrome was lost when age was added to the model. CONCLUSIONS: The frequency of metabolic syndrome increased from the time of the menopausal transition to the postmenopause. Abdominal obesity was the most frequent feature observed. Nevertheless, aging erased the effect of the menopause on the metabolic syndrome. In order to prevent cardiovascular disease, the metabolic syndrome must be evaluated from the time of the menopausal transition.

Adult↗
PubMed2005

Endogenous hypertriglyceridemia intensifies the course of cerulein-induced pancreatitis in rat: relation with changes in the VLDL composition.

AIMS: To study if the course of cerulein-induced pancreatitis in rats changes in a state of triglyceride-rich lipoprotein metabolism alteration. METHODS: Two groups of rats received control diet during a 90-day period (A) and sucrose-rich diet to induce endogenous hypertriglyceridemia (B). Subgroups A2 and B2 received i.p. 45 microg cerulein/kg body weight (to induce acute pancreatitis). Histological examination of pancreas tissue, serum pancreatic lipase, lipoprotein profile and VLDL chemical composition were assessed. Then, pancreatic lipase hydrolytic activity on VLDL-triglycerides was evaluated in vitro. RESULTS: Cellular vacuolization was observed in all of the cerulein-injected rats, but only in subgroup B2 fat necrosis was present. Serum triglycerides were higher in subgroup B1 than in subgroup A1 (mean +/- SEM, mg/dl 123,77 +/- 25.7 vs. 65.8 +/- 7, p < 0.01). Triglycerides from rats fed with sucrose-rich diet, decreased after cerulein-induced pancreatitis (80.38 +/- 11.3 vs. 123,77 +/- 25.7, p < 0.02). Moreover, the endogenous hypertriglyceridemic rats showed an increment of VLDL triglyceride content, which decreased when rats were injected with cerulein. A negative correlation was found between VLDL-triglyceride content and serum pancreatic lipase activity (r = 0.58, p < 0.02). The in vitro assay showed a decrease in VLDL-triglyceride content post incubation with pancreatic lipase enriched serum (mean +/- SD: 59.2 +/- 27.7%, p < 0.01). CONCLUSIONS: The endogenous hypertriglyceridemia intensifies the course of cerulein-induced pancreatitis and it could be related to the decrease in VLDL-triglycerides as a consequence of pancreatic lipase hydrolytic activity.

Acute Disease↗
PubMed2004

A new approach to the quantitative measurement of dense LDL subfractions.

OBJECTIVES: Small dense low-density lipoproteins (LDLs) should be considered a major risk factor for cardiovascular disease, but there is still no recommended method for measuring them or expressing clinical values. We measured the dense LDL portion relatively simply by isolating it using density ultracentrifugation and then giving it a relative, quantitative value. DESIGN AND METHODS: Dense LDLs (d=1.048-1.063 g/mL) were isolated from human plasma at the same time as total LDL (d=1.021-1.063 g/mL) by means of sequential ultracentrifugation, and the former was assessed as a percentage of the latter. A receiver operator characteristic (ROC) curve was used to compare the different LDL components as markers of dense LDLs. The proposed method was compared with non-denaturing gradient gel electrophoresis (NDGGE). In order to obtain clinical data, the dense LDL portion was measured in diabetic and postmenopausal subjects and healthy controls. RESULTS: The ROC curve showed that cholesterol level was a more accurate marker of dense LDLs. The within-run precision (CV) was 2.28%, and the between-run CV was 5.1%. Analytical recovery was 80.2+/-1.6%. The correlation between the proposed method and NDGGE was r=0.90, p<0.001. The dense LDL percentage significantly correlated with serum triglyceride (r=0.57, p<0.001) and high-density lipoprotein cholesterol levels (r=-0.33, p<0.01), but not with the LDL-cholesterol/apolipoprotein B ratio. The diabetic patients and postmenopausal women had higher dense LDL values than the healthy controls. CONCLUSIONS: The results obtained using this procedure are in line with those obtained using NDGGE, which is the conventional assay system for measuring LDL size. Determining the small dense LDL portion by means of its cholesterol content may be a better approach to characterising the risk of cardiovascular disease, even in the presence of relatively normal LDL-cholesterol levels.

Adult↗
PubMed2004

Lipid and lipoprotein profile in menopausal transition. Effects of hormones, age and fat distribution.

The behavior of lipoproteins during the menopausal transition and their relationship with sex hormones and body fat distribution is still unclear. Our aim was to evaluate atherogenic IDL, LDL, Lp(a) and antiatherogenic HDL lipoproteins in four groups of women: premenopausal (n = 20), menopausal transition women with menstrual bleeding (n = 31), menopausal transition women with 3 to 6 months amenorrhea (n = 36), and postmenopausal women (n = 30). We also measured their FSH, LH and estradiol levels along with BMI and waist circumference. Menopausal transition and postmenopausal women showed higher values of waist circumference (p < 0.0032), LDL-cholesterol (p < 0.002), IDL-cholesterol (p < 0.002) and apoprotein B (p < 0.0001) than premenopausal women. Total-cholesterol (p < 0.0001), triglycerides (p < 0.004), IDL-cholesterol and Lp(a) were higher in menopausal transition women with amenorrhea and in postmenopausal women in comparison with premenopausal women. After adjustment according to age and waist circumference, multiple regression analysis showed the increase in total-cholesterol and LDL-cholesterol to be linearly associated to menopausal status and estradiol concentration, whereas Lp(a) was only related to menopausal status. Age was found to be an independent variable in relation to apoprotein B concentration changes. The effect of menopausal status on TG levels did not remain in the model when age, waist and BMI were included (beta = 0.05, p = 0.356). HDL-cholesterol levels were the same in all the groups. Menopause, age and the increase in abdominal fat distribution were three independent and significant factors impairing lipoprotein profiles from the beginning of the menopausal transition.

Adipose Tissue↗
PubMed2002

Impact on lipoprotein profile after long-term testosterone replacement in hypogonadal men.

Testosterone serum levels may influence the lipoprotein metabolism and possibly atherogenic risk. Our aim was to investigate the effects of long-term testosterone supplementation in hypogonadal men on multiple lipoprotein markers. 18 Hypogonadal men were studied before and after 3, 6, and 18 (n = 7) months of treatment with testosterone enanthate. During treatment, serum testosterone and estradiol increased, reaching normal levels (p < 0.0001 and 0.003, respectively). This was associated with a decrease in HDL cholesterol (from 1.40 +/- 0.10 mmol/l to 1.22 +/- 0.08 mmol/l, p < 0.001) after six months at the expense of HDL2 cholesterol (p < 0.01), as well as apoprotein A1 (from 139 +/- 3.4 mg/dl to 126 +/- 3.0 mg/dl, p < 0.005). Hepatic lipase activity increased (p < 0.05) and correlated positively with testosterone (r = 0.56, p < 0.02) and negatively with HDL cholesterol (r = - 0.58, p < 0.02). Total and LDL cholesterol, triglycerides, and apoprotein B did not increase. Among the seven patients who completed 18 months of treatment, triglycerides, total cholesterol, LDL and HDL cholesterol, as well as total cholesterol/HDL cholesterol ratio values did not differ from baseline while apoprotein A1 (p < 0.03) and HDL cholesterol (p < 0.015) remained decreased and hepatic lipase unchanged. Restoration of testosterone levels in hypogonadal men in this study did not reveal unfavorable changes based on total cholesterol/HDL cholesterol and LDL cholesterol/apoprotein B ratios, which are both atherogenic risk markers. Whether the changes in light of lipoprotein metabolism will adversely influence cardiovascular risk over time remains to be determined.

Adult↗
PubMed2002

Kinetics of in vitro lipolysis of human very low-density lipoprotein by lipoprotein lipase.

BACKGROUND AND AIM: An initial step in the catabolism of triglyceride-rich lipoprotein involves the hydrolysis of the triglyceride moiety by lipoprotein lipase (LPL). As differences in the lipolytic behaviour of very low-density lipoprotein (VLDL) particles have been observed, it is possible that different VLDL particles have a different affinity to the enzyme, which means that their fate may partially depend on the LPL-mediated hydrolysis of their triglyceride content. Our aim was to determine whether variation in VLDL chemical composition affects their properties as a substrate for LPL. METHODS AND RESULTS: Isolated VLDL was incubated in vitro with bovine LPL to determine substrate affinity. Under optimal assay conditions, free fatty acids were measured and the kinetic indicators for in vitro triglyceride hydrolysis (Km and Vmax) were calculated. VLDL cholesterol (VLDL-C), VLDL-apoB and the cholesterol/triglyceride ratio were assessed and the triglyceride/protein and triglyceride/apoB ratios were calculated as lipoprotein size estimators. VLDL-C, VLDL-apoB and the VLDL-C/triglyceride ratio positively correlated with Km: r = 0.52, p < 0.01; r = 0.52, p < 0.03; r = 0.69, p < 0.001 respectively. No correlation was found between the VLDL-triglyceride/protein or the VLDL-triglyceride/apoB ratios and Km (r = -0.20, and -0.06 respectively, p = not significant). Of the subjects' anthropometric characteristics, only the waist/hip ratio significantly correlated with Km: r = 0.63, p < 0.01. CONCLUSIONS: In the present study, we investigated the substrate function of VLDL particles in vitro. Enzyme affinity seems to be associated with cholesterol-triglyceride content or the number of VLDL particles rather than particle size. It may be expected that VLDL with a low cholesterol/triglyceride ratio will be efficiently lypolised by LPL, thus leading to the formation of a smaller particle with atherogenic potential.

Animals↗
PubMed1989

Respiratory failure in asthma during the third trimester: report of two cases.

We are reporting the cases of two pregnant women with life-threatening asthma, who required mechanical ventilation of the lungs and later were delivered of healthy infants. Maintenance of an adequate PaO2 is essential in such cases. To accepted asthma therapy, we added a warm metaproterenol-saline solution irrigation and suction, which functions like bronchoalveolar lavage to facilitate recovery.

Adult↗
PubMed1987

Vomiting as a dominant symptom of asthma.

These three cases are presented as additional evidence that vomiting can be a dominant symptom of asthma. Coughing and wheezing can be overlooked or ignored. Asthma must be considered in the differential diagnosis of vomiting.

Adult↗
PubMed1984

The vomiting asthmatic.

Attention is called to vomiting as a major manifestation of asthma. The diagnosis requires only careful history and examination. Symptoms respond well to therapy for asthma. Asthma should be included in the differential diagnosis of recurrent or severe vomiting. If this is done, unnecessary diagnostic procedures can be avoided and proper therapy can be promptly instituted.

Asthma↗
PubMed1975

Adrenalin treatment for hereditary angioneurotic edema.

In two patients studied with HAE the repeated use of 1.0 cc of 1:1000 epinephrine every hour for episodes threatening the upper airway resulted in both subjective and objective improvement of signs and symptoms in a manner we interpret as helpful. No harmful side effects have been encountered in these two young, otherwise healthy, people. Until a more definite therapy is found, we believe repeated high doses of adrenalin should be considered in young patients with HAE presenting with symptoms and signs of airway involvement.

Adult↗