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PubMed1997

Serum immunoreactive leptin concentrations in a Canadian aboriginal population with high rates of NIDDM.

OBJECTIVE: To better understand the relationship between leptin and the anthropometric and physiological variables associated with diabetes, we measured this protein in an isolated Canadian aboriginal population with very high rates of NIDDM. RESEARCH DESIGN AND METHODS: There were 728 individuals aged 10-79 years who participated in a population-based survey to determine the prevalence of NIDDM and its associated risk factors. Fasting blood samples for glucose, insulin, triglyceride, and leptin were collected; a 75-g oral glucose tolerance test was administered and a second blood sample drawn after 120 min. Height, weight, and waist and hip circumference were determined, and percent body fat was estimated using biological impedance analysis. Fitness level was assessed in a subsample of individuals using a validated submaximal step test. The relationship between serum leptin and the other variables was assessed using Spearman's correlation coefficients and multiple linear regression. RESULTS: Serum leptin concentration was strongly correlated with adiposity, and levels were substantially higher in female subjects in all age-groups. For male subjects, percent body fat, fasting insulin level, and waist circumference were significant independent predictors of log serum leptin concentration in a multiple linear regression model (R2 = 0.582). For female subjects, these variables plus glucose tolerance status were included in the final model (R2 = 0.633). Fitness level, when included with the main effects of the above models, was a significant predictor for male subjects only. CONCLUSIONS: In an isolated aboriginal community with high rates of diabetes, we found significant independent relationships between leptin and percent body fat and between leptin and fasting insulin. As documented in other populations, the higher leptin concentration among female subjects may reflect differential leptin production from different adipose tissue beds, or leptin resistance. Independent relationships also existed among leptin and glucose tolerance status in female subjects and fitness level in male subjects.

Adolescent↗

PubMedDate not supplied

Semen analysis in men from Mérida, Venezuela, over a 15-year period.

To determine the possible changes in semen quality of Venezuelan men from 1981 to 1995, a retrospective analysis of semen volume and sperm concentrations was carried out for 2313 men from infertile couples. According to the sperm counts the sample was categorized in four groups: A, 0 sperm; B, <20 x 10(6) sperm/mL; C, 20-200 x 10(6) sperm/mL; D, 2200 x 10(6) sperm/mL. The percentage of men in each group was 9.1, 18.8, 63. 1, and 9.0%, respectively. The frequency of azoospermia and oligozoospermia (groups A and B) did not change over the last 15 years. On the contrary, the frequency showed a significant increase in group C and a decrease in group D. The range of the means of semen volume was 2.6-3.6 mL, linear regression analysis did not show a decrease in seminal fluid volume over time. The range of the means of sperm concentrations were 6.2-12.0 x 10(6) sperm/mL, 73-100 x 10(6) sperm/mL), and 230-340 sperm x 10(6)/mL in groups B, C, and D, respectively. Linear regression analysis revealed a significant reduction in the means of sperm concentrations only in group D. Excluding the azoospermic group, the analysis of pooled data (B + C + D), did not show a significant change in the means of sperm density throughout time. In the semen samples with sperm counts below 200 x 10(6)/mL the means of sperm concentration did not change in the 15-year period of observation.

Adult↗

PubMed1995

[Relative hypoparathyroidism associated with CAPD treatment using normo-calcemic (3.5mEq/1) dialysate: an approach from transperitoneal calcium balance].

We investigated factors affecting net transperitoneal calcium balance (Ca-BL) and the level of parathyroid hormone in relation to stepwise changes in serum calcium, by short PET (peritoneal equibrium test during 240 min: using 2000 ml of 2.5% dextrose dialysate containing 1.75 mmol/L Ca) in uremic patients undergoing stable CAPD. We calculated Ca-BL (mg/effluent/PET) of 244 effluents obtained from 90 patients receiving calcium carbonate as a phosphate binder without vitamin D supplementation. Their serum calcium level corrected with albumin (cSCa), alkaline phosphatase activity (ALP) and intact-PTH level was 9.7 +/- 0.9 mg/dl, 236 +/- 83 mIU/ml and 153.0 +/- 172.4 pg/ml, respectively. We proposed two statistic significant regression lines between Ca-BL and total drainage effluent volume (Ca-BL = 133X - 0.056: r = 0.981, P < 0.001), cSCa (Ca-BL = -12.9X + 123.6: r = 0.941, P < 0.01). Total drainage volume (TDV) and cSCa were two major factors affecting Ca-BL. A TDV level of 2430 ml/240 min-PET or more was required for positive Ca-BL in cases with 9.5-10.0 mg/dl of cSCa, using this linear regression analysis. A cSCa level of 9.6 mg/dl or more was also required for positive Ca-BL in cases with 2400-2600 ml/240min-PET. We also proposed a significant linear regression line between the intact-PTH level and cSCa (i-PTH = -90.5X + 1015.8, r = 0.973, P < 0.01). This line suggest that 200 pg/ml of intact PTH was obtained by 9.0 mg/dl or less of cSCa level in 90 CAPD uremic patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1996

Effects of the water-soluble fraction of partially combusted crude oil from Kuwait's oil fires (from Desert Storm) on survival and growth of the marine fish Menidia beryllina.

Effects of the water-soluble fraction of partially combusted crude oil (PCCO) from oil fires in Kuwait on survival and growth of the marine fish Menidia beryllina were studied relative to those of Kuwaiti crude oil (CO). Survival was studied as a function of total petroleum hydrocarbon concentrations [TPH] in 96-hr static exposures. The specific growth rate (SGR) and specific growth inhibition (SGI) percentage were studied as a function of [TPH] in 16-day flowthrough exposure. Survival in the highest PCCO-associated exposure ([TPH] = 0.64 mg/liter) declined from 95% after 48 hr to 60% at 120 hr of exposure. Linear regression analysis of the [TPH]-SGR relationships resulted in statistically significant (P < 0.001) concentration-dependent decrease of 0.19 in SGR of fish exposed to PCCO water-soluble fraction and of 9.6 x 10(-3) in SGR of fish exposed to CO water-soluble fraction. Linear regression analysis of the [TPH]-SGI relationships showed statistically significant (P < 0.001) concentration-dependent increase of 3.38% per TPH concentration unit (mg/liter) in SGI of fish exposed to PCCO water-soluble fraction, whereas the increase in SGI observed under CO exposures was 0.18% per TPH concentration unit. The toxicity of PCCO was exhibited at a much lower TPH concentration; the EC50 of PCCO was reached at a water TPH concentration of 12.42 mg/liter, while the EC50 of CO was reached at a water TPH concentration of 193.23 mg/liter. The comparative toxicity of the CO and PCCO water-soluble fractions and the difference in their chemical and physical characteristics suggest that the larger contribution of polycyclic aromatic hydrocarbons and other breakdown products to the concentration of PCCO-associated TPHs in water resulted in a larger effect on growth of the marine fish M. beryllina.

Animals↗

PubMed1993

Cross-calibration of DXA equipment: upgrading from a Hologic QDR 1000/W to a QDR 2000.

In this study, the cross-calibration of a fan beam DXA system (Hologic QDR-2000) to a pencil beam scanner from the same manufacturer (Hologic QDR-1000/W) is described. The scanners were calibrated by the manufacturer using the same anthropomorphic spine phantom at installation. To verify consistent machine calibration, a group of 69 female subjects, aged 46-75, had anteroposterior (AP) spine and proximal femur scans on the QDR-1000/W followed by pencil and array scans of the same sites on the QDR-2000 during the same visit. Many of the subjects had bilateral examinations of the proximal femur for a total of 123 hip scans. Pencil and array area, bone mineral content (BMC), and bone mineral density (BMD) from the QDR-2000 were compared with the values obtained on the QDR-1000/W, and linear regression equations were derived for relating the two instruments. At the spine, no differences were found between the QDR-1000/W BMD values and the QDR-2000 array BMD values. A slight difference between pencil beam modes was detected but was not deemed clinically significant. Linear regression models relating the QDR-2000 and QDR-1000/W AP spine BMD measurements showed correlation coefficients greater than 0.99, with slopes of 1.00, intercepts equivalent to zero, and small root mean square errors. Comparisons at the proximal femur showed equivalency at the femoral neck and trochanter regions for the two machines in pencil mode, but slight increases in BMC and BMD at the other femoral sites on the QDR-2000 in both pencil and array mode. Correlation coefficients were 0.97-0.99 for all measurement regions except for Ward's.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗

PubMed2003

Clarifying gender interactions in multivariate analysis.

OBJECTIVES: To examine a linear regression model to predict physical fitness using an alternative concept to analyse gender interactions. METHODS: Data were obtained from the Berne Lifestyle Panel, a survey on health and lifestyles of 56-66 years old Bernese citizens. A measure of physical fitness was regressed on gender, education and their interaction as central explanatory variables and age as confounding factor. For ease of interpretation, two dummy variables of education are introduced, one for female, the other for male education. The model with education dummy variables is compared to a linear regression model without interaction stratified by gender, and with a model with the multiplicative gender-education interaction term without stratification. RESULTS: The use of dummy variables ensures an accurate description of both women's and men's associations of education with the dependant variable, without losing any explanatory power due to stratification. CONCLUSION: The results show that the use of dummy variables is a rewarding alternative to stratification and conventional gender interaction analysis, providing both sufficient statistical information and a basis for straightforward interpretation.

Aged↗

PubMed2003

[No influence of urinary nitrate excretion on the goitre prevalence in Germany].

BACKGROUND: It has long been known that nitrate combined with iodiduria < 100 micro gI(-)/l has a goitrogenic effect. The cause is a partial blockage of the sodium- iodide symporter together with a hindrance to iodide absorption in the intestine. 90% of the intake of nitrate is excreted in urine. Therefore nitraturia provides information about the population. The rare epidemiological studies of the influence of NO(3)(-) on goitre are limited to a small selection of older, regional samples. Our aim was to investigate the role of nitrate in the occurrence of goitre in Germany. METHODS: Using random samples from 3,059 clinically healthy persons of both sexes between 18 and 70 years old from all over Germany, we examined nitraturia and the prevalence of goitre or nodules, including the corresponding iodiduria. (Sonography: 7.5 MHz linear transducer; nitrate determination: isocratic ion chromatography; iodide determination: cerium-arsenite method.) Both the NO(3)(-) and the iodide excretion in spontaneous urine were measured in relation to 1 g creatinine. Statistical processing: Mann-Whitney U-Test, correlation analysis, multivariate linear regression analysis. RESULTS: Median for nitraturia: 55.2 mg NO(3)(-)/g creatinine (men 61.5, women 51.5; p < 0.03). Significant increase in regional nitrate excretion from North to South and from East to West. No statistical connection between nitraturia, thyroid size and nodules. In the multivariate linear regression analysis relating to thyroid size/focal lesions, NO(3)(-) played the smallest part among the variables age, gender, body mass index, iodiduria, nitraturia. In the case of iodiduria with < 50 micro g I(-)/g creatinine (n = 71), there was a correlation between nitraturia and thyroid size (r = 0.18; p < 0.05). All persons with a nitraturia of > 60 mg NO(3)(-)/g creatinine (n = 1,166) evidenced a correlation with the thyroid size (r = 0.18; p < 0.01). CONCLUSION: Since alimentary iodine shortage in Germany has been overcome to a large extent (iodiduria 100-200 micro gI(-)/l) and the nitrate content lies clearly below the WHO limit, the goitrogenic effect of nitrate is only of individual and not of epidemiological importance. The slight regional differences in NO(3)(-) excretion are the consequence of the nitrate content in drinking water and have no effect on the thyroid gland.

Adolescent↗

PubMed1989

Ultrastructural morphometric analysis of papillary neoplasms: biological and diagnostic relevance.

Ten papillary adenocarcinomas of thyroid origin (P-Thy), ten papillary adenocarcinomas of ovarian origin (P-Ov), and eight papillary neoplasms of non-thyroid/non-ovarian origin (P-Other) were morphometrically compared using 19 distinct quantitative nuclear and nucleolar parameters as a database for diagnosis. The selected cases consisted of 16 primary and 12 metastatic neoplasms. It was determined that the P-Thy group had a significantly smaller nucleolar area (NuA) and nucleolar perimeter (NuP), and smaller SDs of nuclear area (NA), NuA, and NuP compared with the P-Ov and P-Other groups (P less than .05). The P-Ov group had a significantly smaller SD of NA compared with the P-Other group (P less than .05). The P-Ov group exhibited the greatest variability among the papillary neoplasms. Linear regression analysis indicated that in the P-Thy group alone there was a significant correlation between mean nuclear form factor (4 pi A/P2) and mean NuA (r = -.82; P less than .01), and mean NP and mean NuA (r = +.77; P less than .01). Linear regression analysis also indicated that in the P-Ov group alone, there was a significant correlation between mean NA and mean NuA (r = +.75; P less than .02). Morphometric domains were established using statistically significant sets of variables that distinguished between the groups. The application of three-dimensional computerized cluster analysis techniques indicated that the P-Thy group consistently had the smallest morphometric domains. It was concluded that ultrastructural morphometric analysis of papillary neoplasms has diagnostic potential and reveals interesting biological relationships among distinct nuclear features in the different groups of neoplasms.

Adenocarcinoma, Papillary↗

PubMed2002

Characterization of emissions from burning incense.

The primary objective of this study was to improve the characterization of particulate matter emissions from burning incense. Emissions of particulate matter were measured for 23 different types of incense using a cyclone/filter method. Emission rates for PM2.5 (particulate matter less than 2.5 microm in aerodynamic diameter) ranged from 7 to 202 mg/h, and PM2.5 emission factors ranged from 5 to 56 mg/g of incense burned. Emission rates were also determined using an electrical low pressure impactor (ELPI) and a small electrostatic precipitator (ESP), and emission rates were compared to those determined using the cyclone/filter method. Emission rates determined by the ELPI method were consistently lower than those determined by the cyclone/filter method, and a linear regression correlation was found between emission rates determined by the two methods. Emission rates determined by the ESP method were consistently higher than those determined by the cyclone/filter method, indicating that the ESP may be a more effective method for measuring semivolatile particle emissions. A linear regression correlation was also found between emission rates determined by the ESP and cyclone/filter methods. Particle size distributions were measured with the ELPI, and distributions were found to be similar for most types of incense that were tested. Size distributions by mass typically ranged from approximately 0.06 to 2.5 microm in aerodynamic diameter, with peak values between 0.26 and 0.65 microm. Results indicated that burning incense emits fine particulate matter in large quantities compared to other indoor sources. An indoor air quality model showed that indoor concentrations of PM25 can far exceed the outdoor concentrations specified by the US EPA's National Ambient Air Quality Standards (NAAQS), so incense smoke can pose a health risk to people due to inhalation exposure of particulate matter. Emissions of carbon monoxide (CO), nitric oxide (NO), and sulfur dioxide (SO2) were also measured for seven types of incense. Emission rates of the gaseous pollutants were sufficient to cause indoor concentrations, estimated using the indoor air quality model, to exceed the outdoor concentrations specified by the NAAQS under certain conditions. However, the incense samples that were tested would fill a room with thick smoke under these conditions.

Air Pollutants↗

PubMed2002

Predictive mapping of air pollution involving sparse spatial observations.

A limited number of sample points greatly reduces the availability of appropriate spatial interpolation methods. This is a common problem when one attempts to accurately predict air pollution levels across a metropolitan area. Using ground-level ozone concentrations in the Tucson, Arizona, region as an example, this paper discusses the above problem and its solution, which involves the use of linear regression. A large range of temporal variability is used to compensate for sparse spatial observations (i.e. few ozone monitors). Gridded estimates of emissions of ozone precursor chemicals, which are developed, stored, and manipulated within a geographic information system, are the core predictor variables in multiple linear regression models. Cross-validation of the pooled models reveals an overall R2 of 0.90 and approximately 7% error. Composite ozone maps predict that the highest ozone concentrations occur in a monitor-less area on the eastern edge of Tucson. The maps also reveal the need for ozone monitors in industrialized areas and in rural, forested areas.

Air Pollutants↗

PubMed1992

An assessment of critical anthropometric dimensions for predicting the fit of a half-mask respirator.

The purpose of this study was to determine if facial dimensions for a group of subjects were predictive of the fit factors measured while one brand of half-mask respirator was worn. Fit factors and 12 facial dimensions measured on 30 female and 38 male subjects were analyzed by correlation coefficients; weighted, multiple linear regression; and discriminant analysis. Data were analyzed for all subjects, gender subgroups, a race subgroup (whites only), and race/gender subgroups. Significant correlation coefficients with the log-transformed fit factors were found for four dimensions; four dimensions had significant coefficients in four or more multiple linear regression models. Only two dimensions had significant coefficients in four or more discriminant analysis models. Menton-subnasale (lower face) length was the only dimension included in all three of these groups. Gender-specific regression models had very high coefficient of determination values (R2 > 0.85). Discriminant analysis of the data for all subjects and race/gender subgroups found very good predictive scores for statistical software-generated models and menton-subnasale length alone; these scores were significantly better than those for the model with the respirator test panel dimensions (face length and lip width). These analyses found that facial dimensions were good predictors of respirator fit for those subjects wearing one brand of half-mask respirator. Lower face length was consistently indicated as being correlated or associated with fit. These results would indicate that dimensions other than those currently used may be more appropriate to define a half-mask respirator test panel.

Adult↗

PubMed2006

Renal function and 25-hydroxyvitamin D concentrations predict parathyroid hormone levels in renal transplant patients.

BACKGROUND: Recent guidelines suggest supplementation with ergocalciferol (vitamin D(2)) in chronic kidney disease stages 3 and 4 patients with elevated parathyroid hormone (PTH) levels and 25-hydroxyvitamin D (25OHD) levels <75 nmol/l. These guidelines are also applied to renal transplant patients. However, the prevalence rates of 25OHD deficiency and its association with PTH levels in renal transplant populations have not been extensively examined. We aimed to document the prevalence rates of 25OHD deficiency [defined by serum levels <40 nmol/l (<16 ng/ml)] and insufficiency [<75 nmol/l (<30 ng/ml)] in a single renal transplant centre, and examine its relationship with PTH levels. METHODS: Serum 25OHD and PTH concentrations were measured in 419 transplant patients attending a single renal transplant clinic over a 4-month period. Demographic and biochemical data were also collected, including serum creatinine, calcium, phosphate and albumin. Simple and multiple linear regression analysis were performed. RESULTS: In 27.3% of the patients, 25OHD deficiency was present, and 75.5% had insufficiency. On univariate analysis, 25OHD, serum albumin and estimated glomerular filtration rate (eGFR) were significantly associated with PTH levels (P < 0.0001, P = 0.004 and P < 0.0001, respectively). Multiple linear regression demonstrated that only 25OHD, eGFR and serum phosphate were significantly predictive of PTH levels (R(2) = 0.19, P < 0.0001). In this model, a 75 nmol/l increase in 25OHD will only result in a maximal reduction in PTH of 2.0 pmol/l. CONCLUSIONS: We conclude that 25OHD deficiency and insufficiency are common in renal transplant patients and may exacerbate secondary hyperparathyroidism. However, 25OHD, eGFR and phosphate only account for 19% of the variability in PTH levels. In addition, even a large increase in serum 25OHD levels is likely to result in only a small reduction in PTH. Therefore, alternative approaches to managing hyperparathyroidism in renal transplant recipients rather than supplementation with ergocalciferol are warranted.

Biomarkers↗

PubMed2005

Adaptation of a surface antigen-based ELISA for the detection of antibodies against Neospora caninum in bovine milk.

The aim of the present study was to determine whether an ELISA based on a 38-kDa surface antigen (NcSRS2) of Neospora caninum tachyzoites could be used to examine bovine milk for antibodies against N. caninum. A total of 797 undiluted milk samples from N. caninum-infected herds were examined in the p38-ELISA. Milk results of individual animals were compared with those obtained by the same ELISA for the corresponding serum samples. The linear correlation between milk and serum antibody results of individual animals was characterized by an adjusted R(2) of 0.644. The examination of the two-graph receiver-operating characteristics revealed an optimal cut-off of 0.150 to obtain similar results in the examination of milk and serum. With this cut-off, the test had a specificity and a sensitivity relative to the serum results of 93%. Using this cut-off, excellent agreement was observed between milk and serum results (Kappa 0.85; 95% CI, 0.781-0.920). A cut-off of 0.450 resulted in a specificity of 99% relative to the serum results. At this cut-off, the sensitivity of the test was 80% relative to the serum-ELISA and agreement was slightly lower (Kappa = 0.82; 95%CI, 0.749-0.887). An optimized linear regression model suggests that, in addition to the result in the p38-serum-ELISA, the variables abortion risk (ABRISK) (abortion between 100 and 269 days pregnant) and the age of the animal (AGE) affected the result of the p38-milk-ELISA. The optimized linear regression model had an adjusted R(2) of 0.8501.

Animals↗

PubMed2006

An ecological study on the association of public dental health activities and sociodemographic characteristics with caries prevalence in Japanese 3-year-old children.

The aim of this ecological study was to determine the association of the frequency of dental health activities conducted as public health service and sociodemographic characteristics with caries prevalence in Japanese 3-year-old children using data for each municipality as one unit. Data on caries prevalence in 3-year-old children in 2000 were obtained from 3,251 municipalities (almost all municipalities in Japan). Caries prevalence for each municipality was recalculated using the empirical Bayes estimation model to make adjustments for variations in municipalities with small numbers of children. Explanatory factors included annual frequency of dental health activities such as dental health education and topical fluoride application programs and various sociodemographic characteristics. Multiple linear regression analysis was applied to examine the associations between caries prevalence and annual frequency of dental health activities with adjustment of other sociodemographic variables. Variations in caries prevalence in municipalities with small populations became smaller after being adjusted by the empirical Bayes estimation model. Multiple linear regression analysis showed significant associations of caries prevalence with sociodemographic characteristics such as the proportion of residents with university degrees, total fertility rate, and the proportion of workers in the manufacturing industry (p < 0.001). Annual frequency of topical fluoride application showed a significant but relatively weak association with caries prevalence (p < 0.001), explaining only 0.8% of the total variation in caries prevalence, whereas no correlation was found between caries prevalence and annual frequency of dental health education. It was concluded that the effect of the fluoride application service on caries prevalence in 3-year-old children, although statistically significant, was of far lower clinical significance than sociodemographic characteristics.

Cariostatic Agents↗

PubMed1995

Medication with ursodeoxycholic acid enhances the biliary clearance of polyethylene glycol 900, but not mannitol.

Ursodeoxycholic acid (UDCA) is a nontoxic bile acid currently used in the treatment of different cholestatic diseases. This bile acid is also considered to be a 'hypercholeretic bile acid'. The effects of daily administration of UDCA on bile flow and the bile acid secretion rate in man are not fully known. The aim of this study was to explore the effects by UDCA on bile flow and its different functions. The biliary clearances of polyethylene glycol 900 (PEG 900) and mannitol were measured simultaneously in patients with an indwelling T tube after cholecystectomy. One group (n = 6) were given UDCA (10 mg/kg/day) for at least 14 days before the investigation and a control group (n = 8) received no bile acid treatment. The bile secretion was studied in acute experiments where bile was drained for 6 h. The bile plasma ratio for PEG 900 was 31 and that for mannitol was 0.7 which corresponds well with the results obtained in different animal species. The relationship between bile flow and the bile salt secretion rate, as expressed by linear regression analysis, showed no difference between the 2 groups (control y = 0.22 + 0.012x, r = 0.61, p < 0.001; UDCA y = 0.20 + 0.016x, r = 0.88, p < 0.001). The relationship between the biliary clearance of PEG 900 and the bile salt secretion rate, as expressed with linear regression analysis, showed a significantly steeper slope for the UDCA-treated patients (control y = 8.1 + 0.34x, r = 0.41, p < 0.05; UDCA y = 5 + 1.58x, r = 0.78, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed2002

Endothelin system in normal and hypertensive pregnancy.

Pre-eclampsia complicates approximately 5-7% of pregnancies and it may be deleterious to both maternal and fetal health. In a prospective study, we investigated plasma endothelin (ET)-1 concentration within the 24th and 36th gestational week in non-smoking pregnant women. Thirty women fulfilled the criteria for the diagnosis of pre-eclampsia according to the American College of Obstetricians and Gynaecologists: de novo arterial hypertension after the 20th gestational week in at least two separate measurements and proteinuria of more than 300 mg/l in a random specimen. For comparison, we analysed blood samples from 125 non-pre-eclamptic pregnant women. ET-1 concentrations were higher in pre-eclamptic pregnancies at both time points (mean+/-S.D.: 1.07+/-2.00 versus 0.54+/-0.56 pg/ml, P=0.045 at 24th week; 0.75+/-1.20 versus 0.44+/-0.45 pg/ml, P=0.023 at 36th week). Receiver operating characteristic (ROC) curves revealed a significant interaction between ET-1 plasma concentrations at the 36th week and the diagnosis of pre-eclampsia [area under the curve (AUC)+/-S.E.M.: 0.657+/-0.049, P=0.008] and a cut-off value at 0.30 pg/ml. Multivariate analysis showed a 4.6-fold higher chance (95% confidence interval: 1.7-12.1, P=0.002) for the diagnosis of pre-eclampsia in pregnant women with ET-1 plasma concentration higher than 0.30 pg/ml at the 36th week. Interaction between ET-1 plasma concentration at the 24th week and diagnosis of pre-eclampsia was not significant in ROC curve analysis (AUC+/-S.E.M.: 0.594+/-0.071, P=0.278). Interestingly, we found a strong positive correlation between ET-1 concentration in the 24th and 36th week in linear regression analysis in pre-eclamptic (r=0.99, P<0.001) and non-pre-eclamptic pregnancies (r=0.61, P<0.001) with a slightly, non-significant decrease from the 24th to 36th week (for group means see above), indicating individual plasma ET-1 levels even in non-pre-eclamptic pregnancies. Linear regression analysis showed no correlation between blood pressure or urine protein excretion and ET-1 plasma concentration in non-pre-eclamptic pregnant women. In conclusion, our prospective study indicates that the ET system is, in contrast to most other forms of human hypertension, activated in pre-eclamptic pregnant women.

Adult↗

PubMed1998

The relation of fasting insulin to blood pressure in a multiethnic population: the Miami Community Health Study.

PURPOSE: The aim of this study was to examine the associations among fasting insulin, adiposity, waist girth, and blood pressure among a nondiabetic multiethnic population. METHODS: A cross-sectional study was performed among 25-44-year-old African-Americans (n = 159), Cuban-Americans (n = 128), and non-Hispanic whites (n = 207) selected from Dade County, Florida. Fasting insulin levels were correlated with resting blood pressure level within each ethnic group. The separate effects of percentage body fat and waist girth on the association between blood pressure and insulin were analyzed in multiple linear regression and analysis of covariance. RESULTS: Fasting insulin was positively associated with systolic (r = 0.26-0.39; P < 0.01) and diastolic blood pressure (r = 0.19-0.30; P = 0.10 to P < 0.001) among women of all ethnic groups and among non-Hispanic white men (r = 0.27; P < 0.05). Stepwise linear regression analyses revealed statistically significant associations between systolic and diastolic blood pressure and fasting insulin level in non-Hispanic whites independent of other covariates, including sex and percentage body fat (P < 0.001). Fasting insulin was also independently and significantly related to systolic blood pressure among African-Americans (P = 0.02). Among Cuban-Americans, sex and percentage body fat were the main correlates of blood pressure level. Analysis of covariance revealed a relationship between insulin and blood pressure that was independent of waist girth among men and women. CONCLUSIONS: Fasting insulin level and blood pressure were positively associated among African-Americans and non-Hispanic whites. This association was not entirely due to the common association with percentage body fat or waist girth.

Adipose Tissue↗

PubMed2001

Amniotic fluid lipopolysaccharide-binding protein and soluble CD14 as mediators of the inflammatory response in preterm labor.

OBJECTIVE: Our purpose was to determine the association of lipopolysaccharide-binding protein (LBP) and soluble CD14 (sCD14) with the proinflammatory response among women in preterm labor. The binding of lipopolysaccharide (LPS) with LBP and sCD14 activates macrophages at LPS concentrations up to 1000 times lower than required with LPS alone. LBP and sCD14 in amniotic fluid could explain the high concentrations of cytokines present in the amniotic fluid of culture-positive women and the presence of cytokines in the amniotic fluid of culture-negative women. STUDY DESIGN: A cohort of 169 afebrile women in preterm labor with intact membranes had amniotic fluid collected by transabdominal amniocentesis for culture and for LBP, sCD14, and interleukin 6 (IL-6) determinations by enzyme-linked immunosorbent assay. IL-6 levels of >2 ng/mL were considered elevated. Statistical analyses included analysis of variance, multiple comparisons with Bonferroni correction, and linear regression. RESULTS: All 169 amniotic fluid samples had measurable LBP and sCD14. Subjects were categorized by amniotic fluid culture results and IL-6 concentration into 3 groups: (1) positive amniotic fluid culture, (2) negative amniotic fluid culture, elevated IL-6 concentration, and (3) negative amniotic fluid culture, low IL-6 level. Geometric mean LBP and sCD14 levels differed significantly among groups such that levels were approximately twice as high among pregnancies with positive amniotic fluid culture or elevated IL-6 compared with those without evidence of inflammation (both P <.001). sCD14 was inversely associated with enrollment gestational age independent of amniotic fluid culture results and IL-6 concentrations. Among culture negative, low IL-6 pregnancies, sCD14 decreased 3.5% for each additional week of gestation (95% confidence interval [CI], 0.01%-6.4%; P =.02). LBP levels showed a similar trend in this group (P =.09). One hundred eleven subjects had detectable IL-6 levels. Among these subjects, IL-6 increased by 2.1-fold for every 10-fold increase in LBP (95% CI, 1.1-4.0; P =.02) and by 28.4-fold for every 10-fold increase in sCD14 (95% CI, 10.4-77.4; P <.001) with adjustment for gestational age by linear regression. CONCLUSIONS: LBP and sCD14 are present in amniotic fluid of preterm pregnancies and are linearly associated with amniotic fluid IL-6 concentrations. These molecules may amplify the cytokine response and thereby help explain the presence of cytokines in amniotic fluid when culturable quantities of microbes are absent.

Acute-Phase Proteins↗