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PubMed2001

Tapering off prednisolone and cyclosporin the first year after renal transplantation: the effect on glucose tolerance.

BACKGROUND: Glucose intolerance is an untoward side effect of some immunosuppressive and anti-hypertensive drugs. The primary aim of the present prospective observational study was to test the hypothesis that tapering off prednisolone and cyclosporin (CsA) the first year after transplantation may have beneficial effects on glucose tolerance in renal transplant recipients. METHODS: Ninety-one non-diabetic recipients were included, and 87 patients underwent a 75 g oral glucose tolerance test both 10 weeks and 1 year after renal transplantation. The change over time in 2-h blood glucose was compared with a number of variables potentially influencing glucose tolerance. RESULTS: The proportion of glucose intolerant recipients was reduced from 55 to 34% during the study. Univariate linear regression analysis showed a significant association between the reduction in daily prednisolone dose down to 5 mg and decline in blood glucose (P=0.001), whereas weight gain was associated with increasing blood glucose (P=0.031). Each 1-mg reduction of prednisolone dose leads to an estimated decline in 2-h blood glucose of 0.12 mmol/l based on the multiple linear regression model (P=0.003). Twelve out of 22 patients with post-transplant diabetes mellitus (PTDM) at baseline improved to normal or impaired glucose tolerance. Ten PTDM-subjects who remained diabetic 1 year after transplantation had lower serum insulin levels during the oral glucose challenge, and five patients treated with anti-diabetic drugs at baseline required hypoglycaemic drugs also at follow up. The decline in CsA level of 100 microg/l and the lower number of patients treated with beta-blockers at follow-up, did not alter glucose tolerance significantly. CONCLUSIONS: Tapering off prednisolone, but not CsA, significantly improves glucose tolerance during the first year after renal transplantation.

Adult↗

PubMed2000

Plasma RNA viral load predicts the rate of CD4 T cell decline and death in HIV-2-infected patients in West Africa.

OBJECTIVE: To examine whether the levels of plasma RNA and DNA provirus predict the rate of CD4 cell decline and patient death. DESIGN: Retrospective analysis of HIV-2 cohort subjects. METHODS: Fifty-two subjects were recruited between January 1991 and December 1992. HIV-2 RNA levels in plasma and DNA levels in peripheral blood mononuclear cells (PBMC) were measured using in-house quantitative PCR assays. The annual rate of CD4 cell decline was calculated using the least-squares method. The survival data on 31 December 1997 were used. RESULTS: The mean percentage of CD4 cells at baseline was 30.7 (SD, 9.5). In a linear regression model, the annual rate of CD4 cell decline was 1.76 CD4% faster for every increase in one log10 RNA copies/ml [95% confidence interval (CI), 0.81-2.7; P = 0.0006; r = 0.46; n = 52] and 1.76 CD4% faster for every increase in log10 DNA copies/10(5) PBMC (95% CI 0.46-3.1; P = 0.01; r = 0.33; n = 42). In a multiple linear regression model, RNA load was related to CD4 decline independently of DNA load (P = 0.02). The overall mortality rate was 7.29/100 person-years. In a Cox regression model, the hazard rate increased by 2.12 for each log10 increase in RNA load (95% CI, 1.3-3.5; P = 0.0023) but only by 1.09 for each log10 increase in DNA load (95% CI, 0.64-1.87; P = 0.8). CONCLUSION: This longitudinal study shows for the first time that a baseline HIV-2 RNA load predicts the rate of disease progression. HIV-2-infected patients with a high viral load may need to be treated as vigorously as HIV-1 patients.

Adolescent↗

PubMed2000

Physical activity level is an independent predictor of the diurnal variation in blood pressure.

OBJECTIVE: The aim of this study was to define the relationship between physical activity and the magnitude of the percentage fall in blood pressure at night (nocturnal dip). METHODS: We simultaneously monitored 24-h ambulatory blood pressure and measured physical activity by actigraphy in 434 patients. Blood pressure was measured every 20 min; the actigraph integrated an activity score every 10 s. Mean daytime and night-time activity were calculated from mean scores for the 15 min preceding each blood pressure measurement. Nocturnal dip in systolic and diastolic blood pressure (SBP and DBP) were regressed on mean (log-transformed) daytime activity. Mean night-time activity, age, gender, smoking status, body mass index (BMI) and clinic blood pressure were added into a multiple linear regression. RESULTS: The patient group was heterogeneous in age, gender and mean 24-h blood pressure. Mean daytime activity level was significantly and positively associated with the magnitude of the nocturnal dip in both SBP and DBP. Increased night-time activity was significantly associated with a smaller nocturnal dip. Older patients had a smaller nocturnal dip per log unit daytime activity. Nocturnal dip in SBP was greater in males, and smaller in those taking antihypertensive medications. Smoking, BMI and clinical blood pressure level were not associated with the extent of the nocturnal dip after adjustment for other factors. CONCLUSIONS: Daytime and night-time physical activity levels are independently and significantly predictive of the magnitude of the nocturnal dip in blood pressure. Variation in activity may confound interpretation of 24-h ambulatory blood pressure monitoring, and contribute to the poor reproducibility of dipper status.

Adult↗

PubMed1992

Whole-brain irradiation and decline in intelligence: the influence of dose and age on IQ score.

PURPOSE: Decline in intelligence can occur after whole-brain cranial irradiation for childhood malignancy. The purpose of this analysis was to estimate better the impact of dose and age at time of irradiation on IQ decline. PATIENTS AND METHODS: A total of 48 children were studied. We combined two previously reported studies that included 15 patients with pediatric acute lymphocytic leukemia (ALL) and 18 pediatric patients with medulloblastoma/posterior fossa primitive neural ectodermal tumors (PNETs) in whom serial IQ tests were administered. Another 15 patients (nine ALL and six PNET) were studied subsequent to these reports. This experience included ALL patients who were treated with whole-brain irradiation at doses of 18 Gy (n = 9) and 24 Gy (n = 15), and PNET patients who were treated with 18 Gy (n = 5), 22 to 24 Gy (n = 2), and 32 to 40 Gy (n = 17). Multiple regression models were constructed to estimate expected IQ score after treatment based on initial IQ score, age at treatment, and dose of whole-brain irradiation. RESULTS: Using a multiple linear regression model to correct for initial IQ and age at treatment, patients who received a dose of 36 Gy to the whole brain were estimated to score 8.2 points less on IQ testing than those with 24 Gy (95% confidence interval [CI], 1.8 to 14.6) and 12.3 points less than those who received 18 Gy (95% CI, 2.7 to 21.7). Older age at the time of irradiation resulted in less decline in subsequent IQ score. The predicted IQ decline is 11.9 points less in a 10-year-old patient than in a 3-year-old patient (95% CI, 4.2 to 19.6) for equivalent doses of irradiation. The model to predict IQ accounts for half the total variation in IQ score. There was no significant difference between the coefficients that reflected IQ decrease from radiation dose between subgroups who had ALL versus those with PNET. CONCLUSIONS: One can forecast final IQ score based on the initial IQ score, dose of irradiation, and age at time of irradiation. Our findings should aid in the selection of appropriate therapy when whole-brain irradiation is needed.

Adolescent↗

PubMed2004

Association of breastfeeding with maternal control of infant feeding at age 1 year.

OBJECTIVE: Previous studies have found that breastfeeding may protect infants against future overweight. One proposed mechanism is that breastfeeding, compared with bottle-feeding, may promote maternal feeding styles that are less controlling and more responsive to infant cues of hunger and satiety, thereby allowing infants greater self-regulation of energy intake. The objective of this study was to examine whether preponderance of breastfeeding in the first 6 months of life and breastfeeding duration are associated with less maternal restrictive behavior and less pressure to eat. METHODS: We studied 1160 mother-infant pairs in Project Viva, an ongoing prospective cohort study of pregnant mothers and their children. The main outcome measures were mothers' reports of restricting their children's food intake and of pressuring their children to eat more food, as measured by a modified Child Feeding Questionnaire (CFQ) at 1 year postpartum. Restriction was defined by strongly agreeing or agreeing with the following question from the modified CFQ: "I have to be careful not to feed my child too much." We derived a continuous pressure to eat score from 5 questions of the modified CFQ. We used multiple logistic regression to examine the association between preponderance of breastfeeding in the first 6 months of life, breastfeeding duration, and mothers' restriction of children's access to food. We used multiple linear regression, both before and after adjusting for several groups of confounders, to predict the effects of breastfeeding on the mothers' scores for pressuring their children to eat. RESULTS: The mean (SD) age of the women was 32.4 (4.8) years; 24% of the women were nonwhite, and 32% were primigravidas. At 6 months postpartum, 24% of the mothers were exclusively breastfeeding, 25% were mixed feeding, 41% had weaned, and 10% had fed their infants formula only. The mean (SD) duration of breastfeeding was 6.3 (4.5) months. Thirteen percent of the mothers strongly agreed or agreed with the restriction question. The mean (SD) score on the pressure to eat scale was 5.3 (3.7), and the range was 0 to 20. After adjusting for mothers' preexisting concerns about their children's future eating and weight status, as well as sociodemographic, economic, and anthropometric predictors of breastfeeding duration, we found that the longer the mothers breastfed, the less likely they were to restrict their children's food intake at age 1 year. The adjusted odds ratio was 0.89 (95% confidence interval [CI]: 0.84-0.95) for each 1-month increment in breastfeeding duration. In addition, we found that compared with mothers who were exclusively formula feeding, mothers who were exclusively breastfeeding at 6 months of age had much lower odds of restricting their children's food intake at 1 year (odds ratio: 0.27; 95% CI: 0.10-0.72). Preponderance of breastfeeding in the first 6 months of life and breastfeeding duration (beta = -0.01 points on the 0-20 scale for each additional 1 month of breastfeeding [95% CI: -0.07 to 0.05]) were not related to mothers' pressuring their children to eat more. CONCLUSION: Mothers who fed their infants breast milk in early infancy and who breastfed for longer periods reported less restrictive behavior regarding child feeding at 1 year. Additional longitudinal studies should examine the extent to which any protective effect of breastfeeding on overweight is explained by decreased maternal feeding restriction.

Adult↗

PubMed1996

Availability for poults of phosphorus from meat and bone meals of different particle sizes.

Two experiments were conducted to compare the dietary availability of P from meat and bone meal (MBM) with that of P from dicalcium phosphate (DP) for poults. Two batches of the same MBM were tested. The batches differed in fineness of grind; one was passed through a 10-mesh screen (openings of 2.03 mm) (MBM1O) and the other through a 12-mesh screen (openings of 1.91 mm) (MBM12). In Experiments 1 and 2, the low-P basal diets contained, by analysis, 0.54% P (0.2% nonphytate P) and 0.64% P (0.3% nonphytate P), respectively. Each batch of MBM and DP were included in isocaloric, equinitrogenous diets to obtain increments of 0.1, 0.2, 0.3, and 0.4% P added to the basal diet. Three pens, each containing seven poults, were assigned to each of the 13 dietary treatments. Poults were fed the diets from 5 to 11 and 6 to 13 d of age in Experiments 1 and 2, respectively. Regression analyses of the data showed that increases in BW and tibia ash were linearly related (P </= 0.01) to percentage dietary P and to quantity of P consumed. Common intercept multiple linear regression was used to derive relative availabilities (RA) with DP assigned a value of 100. On the basis of BW gains, RA of MBM1O and MBM12 ranged from 99.1 to 105.5, depending on the independent variable and the experiment. Similarly, on the basis of tibia ash, RA ranged from 97.3 to 104.8. None of the RA differed (P > 0.05) from 100. Thus, the RA of P from MBM tested were equal to that of P from DP, and particle size of the MBM did not affect RA of P.

Animals↗

PubMed2002

Raised maternal serum placenta growth factor concentration during the second trimester is associated with Down syndrome.

OBJECTIVES: To compare early second-trimester maternal serum placenta growth factor concentrations in Down syndrome pregnancies and those in normal pregnancies. METHODS: A case-control study was performed to evaluate the maternal serum placenta growth factor concentrations in 36 Down syndrome and 320 normal pregnancies with matched gestational age during the second trimester. For the detection of serum concentrations of placenta growth factor, a quantitative sandwich enzyme immunoassay technique (R & D Systems Inc., Minneapolis, Minnesota, USA) was performed. RESULTS: Using a multiple linear regression model, maternal serum placenta growth factor level was associated with gestational age (p<0.001) and the existence of Down syndrome pregnancy (p<0.001). After converting maternal serum placenta growth factor concentrations of each analyte to multiples of the appropriate gestational median (MoM), placenta growth factor MoM (p<0.001) was revealed to be an independent variable for Down syndrome pregnancies after adjusting for the effects of maternal age (p<0.001), free beta-hCG (p<0.001) and AFP (p=0.014) by multivariate logistic regression analysis. CONCLUSIONS: Maternal serum placenta growth factor concentration was elevated in Down syndrome pregnancies during the early second trimester. Placenta growth factor might be a novel marker for maternal serum Down syndrome screening.

Biomarkers↗

PubMed1993

Oral contraceptive use and blood pressure levels among women workers in São Paulo, Brazil.

Oral contraceptive use has been increasing in Brazil since the late 1970s, and oral contraceptives have been associated with higher incidence of cardiovascular diseases, including hypertension, since their release in the United States and Europe. We examined the association between oral contraceptive use and blood pressure levels in 1457 workers from 10 sectors of the economy, between the ages of 15 and 49 years, in São Paulo, Brazil. Oral contraceptive use was associated with higher age, lower parity, higher income, white ethnic group, and administrative occupations. Using multiple linear regression and logistic regression techniques, we evaluated blood pressure and hypertension differences between users and nonusers. Oral contraceptive users had a mean systolic blood pressure 2.6 mm Hg higher than nonusers after adjustment for multiple potential confounders, including age, income, parity, ethnicity, body mass index, and occupation. There was a statistically significant positive trend between length of time on oral contraceptives and mean systolic blood pressure levels. After adjustment for demographic and social variables, there were no differences between whites and blacks. Oral contraceptive users have an adjusted odds ratio for hypertension of 2.66 (95% CI: 1.51-4.70). The finding of an increasingly positive association between oral contraceptive use and mean systolic blood pressure level suggests cause and effect. This observation has substantial importance because systolic blood pressure is considered the primary predictor of blood pressure-associated morbidity and mortality. This may pose a particular problem in Brazil, since most women on oral contraceptives are not under medical supervision.

Adolescent↗

PubMed1992

Determinants of plasma fibrinogen: relation to body weight, waist-to-hip ratio, smoking, alcohol, age, and sex. Results from the second MONICA Augsburg survey 1989-1990.

In the second World Health Organization MONItoring Trends and Determinants in CArdiovascular Disease (MONICA) Augsburg survey in 1989-1990 (n = 4,940), the association between nephelometric plasma fibrinogen level and lifestyle-related potential determinants was assessed in 4,434 subjects aged 25-74 years (89.8% of participants). Irrespective of pregnancy and the use of oral contraceptives, crude fibrinogen values were consistently higher in women than in men of all ages (age-standardized difference, 12.2 mg/dl; 95% confidence interval, 7.0-17.4 mg/dl). Fibrinogen concentrations were positively correlated (p less than or equal to 0.0001) with age, body mass index, and waist-to-hip ratio in both sexes and with cigarette smoking in men and were negatively correlated with alcohol consumption in both sexes. In multiple linear regression analyses using categorized determinants as independent variables, a strongly J-shaped relation for body mass index in women and a linear association for waist-to-hip ratio in men were revealed. Smoking had a dose-dependent effect on fibrinogen concentration in men but a lesser effect in women. For alcohol consumption a U-shaped association was found, particularly in men. The curvilinear relations were confirmed in multiple polynomial regression models using continuous determinant variables. The potential epidemiological impact of a determinant was assessed by calculating differences in adjusted fibrinogen concentrations associated with the 10th and 90th percentile values of the determinant distributions actually observed among the study participants. This impact on the population fibrinogen level was most pronounced for age in both sexes, followed by body mass index, cigarette smoking, and alcohol consumption in women and by smoking, waist-to-hip ratio, and alcohol consumption in men.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗

PubMedDate not supplied

Diagnostic tools to determine the quality of "transparent" regression-based QSARs: the "modelling power" plot.

A bivariate plot is presented for comparing two or more QSAR models. It is based on two new statistics associated with a regression model, the "descriptive power" (Dp), which is estimated through the relative uncertainty of model coefficients, and the "predictive power" (Pp), which is estimated through both the fitted and cross-validated explained variance of the response variable (i.e., biological activity). An algorithm was developed for performing equivalent multiple linear regression and partial-least-squares calculations. The results were validated by comparison with widely accepted commercial software. Dp and Pp statistics are defined to vary from 0 to 100%, so the modeler has a intuitive impression of the descriptive (i.e., global importance of the selected descriptors) and predictive (i.e., possibility of performing QSAR or just SAR estimations) power. These statistics represent a point in the Dp versus Pp "modelling power" plot, which facilitates visual multiple models comparison, but also could be used to substitute classical statistics and could even be combined to obtain a unique parameter to define (or compare) the model's quality.

Animals↗

PubMed1978

Failure of total calcium corrected for protein, albumin, and pH to correctly assess free calcium status.

The clinical effectiveness of published algorithms in correcting serum total calcium (CaT) for the effects of protein, albumin, and pH was tested. Corrected calcium (CaC) values obtained by 13 of these methods were compared with values of measured free calcium (CaF) in 55 samples from normal controls and 404 samples from patients with various disorders of calcium metabolism. Three criteria were used to compare either CaC or CaT with measured CaF: 1) the correlation coefficient, 2) the average absolute deviation from measured CaF of the values of CaF predicted by the linear regression of CaF on each CaC, and 3) the number of samples in which CaC or CaT gave a different impression of normality than measured CaF. Application of the 13 published algorithms produced varied results, but none produced substantially better agreement between CaC and CaF than was found between CaT and CaF. The application of additional algorithms derived by multiple linear regression using our data base gave slightly better results than any of the published algorithms, but many values of CaC remained which were disparate from the measured value of CaF. Correction of measured total calcium by using other concurrently obtained chemistry values does not seem to adequately predict calcium status as measured by free calcium.

Autoanalysis↗

PubMed2000

[Knowledge about hypertension and blood pressure level].

BACKGROUND: The improvement of efficacy of the hypertension prevention and patient education largely depend on determination of the hypertension risk factors and increase in knowledge about hypertension. The aim of this study was to assess correlation between the environmental factors and knowledge about hypertension and occasionally measured blood pressure values. MATERIALS AND METHODS: The studied group consisted of 485 subjects, who voluntarily participated in the street-based hypertension screening program in Cracow (summer 1997). All subjects were asked to fill out a questionnaire concerning their health behaviours (i.e. stress, smoking and drinking habits) and a test to evaluate their knowledge about hypertension and its risk factors. The blood pressure measurement were taken using semiautomatic device (Digital Blood Pressure UA-702), in the sitting position, after a rest minimum five minutes. The study group consisted of persons with negative history of hypertension (n = 440), and untreated hypertensive patients (n = 45). In order to assess the influence of different factors on blood pressure level, the subjects were divided into two groups according to the presence or absence of a particular risk factor. In the statistical analysis Student's t-test, chi 2 and linear regression analysis with adjustment for possible confuses were used. All values were presented as mean +/- SD. RESULTS: The mean age was 37.1 +/- 17.8 years. Participants were well educated (75.9% had finished college or high school), and there were more women than men in the study group (57.5% vs 42.5%). 24.1% of participants had blood pressure values exceeding 140/90 mmHg. Multiple linear regression demonstrated that age, body mass index and knowledge about hypertension significantly influenced the level of systolic blood pressure; while only body mass index was among the factors determining diastolic blood pressure. CONCLUSIONS: This study confirms the influence of age, male gender, body mass index, alcohol consumption, stress and the snoring on the blood pressure level. The association between the knowledge about hypertension risk factors or hypertension and occasionally measured blood pressure values has been demonstrated.

Adult↗

PubMed1983

A nonlinear regression-kinetic method for quantification of serum triglycerides.

We report a new kinetic approach to the quantification of triglycerides (triacylglycerols) in human sera. The new approach combines a commercially available enzyme-reagent system with a multiple-linear-regression data-processing method. Values of absorbance collected at 3-s intervals between 20 and 305 s are fitted to a pseudo-first-order model to compute the total change in absorbance expected if the reaction were to proceed to equilibrium. The computed absorbance change varies linearly with triglyceride concentration between 3 and 20 mumol/L (after 250-fold dilution of sample). The pooled relative standard deviation was 7.2% for 23 serum samples with triglyceride concentrations between 3 and 20 mumol/L. Comparison of kinetic (y) and equilibrium (x) absorbance changes for the 23 sera gave a least-squares equation of y = 0.994x + 0.00066, confirming good agreement between the methods. The temperature coefficient is less than 0.2% per degree Celsius.

Humans↗

PubMed1999

The relationship between early age of onset of initial substance use and engaging in multiple health risk behaviors among young adolescents.

BACKGROUND: Previous research based on problem-behavior theory has found that early age of onset of substance use is associated with engaging in multiple health risk behaviors among high school students. It is unknown whether these relationships begin during early adolescence. OBJECTIVE: To examine the relationships between early age of onset of cigarette, alcohol, marijuana, and cocaine use and engaging in multiple risk behaviors among middle school students. METHODS: A modified version of the Centers for Disease Control and Prevention Youth Risk Behavior Survey was administered to 2227 sixth through eighth grade students attending 53 randomly selected middle schools in North Carolina. A Health Risk Behavior Scale was constructed from 16 behaviors, including indicators of violence and weapon carrying; current substance use; nonuse of helmets when biking, in-line skating or skateboarding; not wearing a seat belt; riding with a driver who had been drinking; and suicide plans. Among this sample of middle school students, the scale had a mean (SD) of 4.1 (2.7) (range=O-15), and had a high internal reliability coefficient (alpha(=0.74). The independent variables included first time use of cigarettes, alcohol, marijuana, and cocaine at age 11 years or earlier; actual age of onset of each substance; race and ethnicity; family composition; sex; school grade; academic ranking; and older age for school grade. These data were analyzed with analysis of variance, Spearman r, and multiple linear regression. RESULTS: All the independent variables were found to be associated (P<.005) with the Health Risk Behavior Scale during the bivariate analyses. When each of these significant variables were entered into a multiple regression model, having smoked at age 11 years or younger accounted for 21.9% of the variation in the Health Risk Behavior Scale. Male sex, early marijuana or cocaine use, older age, lower academic rank, white race, and living in a 1-parent family explained an additional 19.1% of variation in the model (adjusted R2=0.41, P<.001). When the actual ages of onset of the use of substances were analyzed, in order of magnitude; age of onset of smoking; male sex; age of onset of alcohol and marijuana use; age; lower academic ranking; age of onset of cocaine use; white race; and lower academic rating accounted for 52.8% (P<.001) of the variation in the Health Risk Behavior Scale. CONCLUSION: Even when considering sociodemographic factors, early age of onset of cigarette use was the strongest correlate of the number of health risk behaviors in which these young adolescents had engaged. Early onset of use of other substances was also associated with a clustering of health risk behaviors among this sample of middle school students. The findings suggest that screening for early experimentation with tobacco and other substance use will help identify young adolescents at increased risk for engaging in multiple health risk behaviors.

Adolescent↗

PubMed1994

Sensitivity of catalyst/base ratio on curing of resin luting agents: polymerization exotherm analysis.

OBJECTIVES: Currently, the proposed test of the International Standardization Organization (ISO) for measuring working and setting times of resin luting agents is based on measurement of times to reach specified stages on the polymerization exotherm. The objective of this study was to use this test to investigate the influence of variations in the mass ratios of catalyst paste to base paste on the working and setting times of three dual-cured dental resin luting agents. METHODS: The materials used were Dicor Light Activated Cement (Dentsply International Inc.), Palfique Inlay Resin Cement (Tokuyama Soda Co.), and Vivadent Dual Cement (Vivadent). Fifteen specimens of each material were tested for working time by spatulating mass ratios from 0.7 to 1.3 for 30s at 23 degrees C and recording the time from beginning of spatulation to the time at which a temperature increase occurs. Ten specimens of each material were tested for setting time by spatulating in a similar manner at 37 degrees C and recording the time at which the temperature reaches a maximum value. RESULTS: The data were fitted to the relation, In t = In A + Bm, where t is the time in seconds, m is the mass ratio, and A and B are regression coefficients. The results suggest that working and setting times of the specimens were independent of variations in mass ratio. A comparison among the materials was made by using a multiple linear regression with the relation, In t = In C + Dm + E gamma + Fm gamma, where gamma is a dummy variable to help distinguish between materials, and C, D, E, and F are regression coefficients. The results suggest that differences in materials influence the working time but not the setting time. SIGNIFICANCE: These results infer that variations in mass ratio (+/- 20%) often observed in the clinical setting should not have a significant influence on the working and setting times of resin luting agents.

Acrylic Resins↗

PubMed2006

Increase of CXC chemokine CXCL10 and CC chemokine CCL2 serum levels in normal ageing.

No study has evaluated contemporaneously serum CXC and CC chemokines changes in normal ageing. Serum levels of CXCL10 (sCXCL10) (CXC) and CCL2 (sCCL2) (CC) prototype chemokines have been measured in 164 healthy subjects, from 10 to 79 years of age (82 males/82 females). By simple regression analysis, sCXCL10 and sCCL2 were significantly related with increasing age (r=0.32, p<0.001; r=0.31, p<0.0001, respectively), and with each other (r=0.30, p=0.0004). In a multiple linear regression model, only age and sCCL2 were significantly related to sCXCL10 levels (p<0.001); age and sCXCL10 were significantly related to sCCL2 levels (p<0.001). Subjects with high sCXCL10 levels (>150 pg/ml) were not significantly associated with those with high sCCL2 levels (>559 pg/ml). This study, performed in healthy subjects on an age gradient, demonstrates an increase of sCXCL10 and sCCL2 with advancing age; the differential increase of sCXCL10 or sCCL2 may reflect a general shift towards Th1 or Th2 cytokines pattern, respectively.

Adolescent↗

PubMedDate not supplied

Effects of multimicronutrient supplementation on helminth reinfection: a randomized, controlled trial in Kenyan schoolchildren.

A randomized, placebo-controlled, double-blind, two-by-two factorial trial was carried out among 977 schoolchildren from 19 primary schools in Nyanza Province, Kenya from February 1995 to February 1996. The interventions were multimicronutrient supplementation (vitamin A, 1000 micrograms; vitamin B1, 1.4 mg; vitamin B2, 1.6 mg; vitamin B6, 1.7 mg; vitamin B12, 2.0 micrograms; folate, 150 micrograms; niacin, 16 mg; vitamin C, 50 mg; vitamin D, 5 micrograms; vitamin E, 8 mg; iron, 18 mg; zinc, 20 mg; copper, 2.0 mg; iodine, 150 micrograms; selenium, 40 micrograms) and multihelminth chemotherapy (albendazole 600 mg in a single dose and/or praziquantel 40 mg/kg in a single dose). This paper reports the effects of the supplementation given on all school days on reinfection with hookworm, Ascaris lumbricoides, Trichuris trichiura and Schistosoma mansoni after 11 months. Baseline prevalence and geometric mean intensity for hookworm, A. lumbricoides, T. trichiura and S. mansoni in all children investigated were 54.7%, 13.8%, 45.6% and 70.0%, respectively and 8.6, 2.7, 5.9 and 19.4 eggs per gram (epg), respectively. Children received a mean of 2.3 multimicronutrient/placebo tablets per school week, giving a compliance rate of 46%. Children given multimicronutrients had a slightly, but significantly, lower intensity of S. mansoni reinfection compared with children given placebo (5.5 epg vs. 7.7 epg, P = 0.047). Multiple linear regression analyses controlling for baseline infection status confirmed this, as children who received micronutrients were reinfected with S. mansoni at only 69% of the intensity of those who received placebo. Multiple logistic regression analyses revealed that micronutrient supplementation was associated with a lower S. mansoni reinfection rate (odds ratio = 0.7) although this was only of borderline significance (P = 0.090). There were no significant differences in reinfection rates or intensities of hookworm, A. lumbricoides and T. trichiura. The effect on S. mansoni infection intensity is particularly interesting given the low compliance, suggesting that full micronutrient supplementation might have a role to play in S. mansoni control programmes.

Adolescent↗

PubMed2003

Bias in assessment of health-related quality of life in a hemodialysis population: a comparison of self-administered and interviewer-administered surveys in the HEMO study.

ABSTRACT. Examined is the relationship of patient-reported health-related quality of life (HRQOL) to the mode of survey administration in the Hemodialysis Study. In addition to self-administered surveys to assess HRQOL, interviewer-administered surveys were made available to include patients with poor vision, decreased manual dexterity, or strong preference. For examining the predictors of participation by self-administration of the survey, multiple logistic regression was performed. For examining the relationship of HRQOL results to mode of survey administration, adjusted differences between the self-administered and interviewer-administered groups were obtained from multiple linear regression models accounting for sociodemographic and case-mix factors. A total of 978 of the first 1000 subjects in the Hemodialysis Study completed the survey by interview (n = 427) or by self-administration (n = 551). The interviewer-administered group was older, was more likely black, had longer duration of ESRD, had a higher prevalence of diabetes, and had more severe comorbidity (all P < 0.01). After adjustment for these differences, patients in the interviewer-administered group had higher scores on scales that measured Role-Physical, Role-Emotional, and Effects of Kidney Disease (all P < 0.001). Dialysis studies that restrict HRQOL measurement to patients who are able to complete surveys without assistance will not accurately represent the health of the overall hemodialysis population. Clinical studies and clinical practices using HRQOL as an outcome should include interviewer administration or risk a selection bias against subjects with older age, minority status, and higher level of comorbidity. Future investigation should include research of survey modalities with a low response burden such as telephone interview, computer-assisted interview, and proxy administration.

Adolescent↗