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Insulin-like growth factor I as a predictor of cortical bone mass in a long-term study of ovariectomized and estrogen-treated rats.

The relationship between serum insulin-like growth factor I (IGF-I) and cortical bone mass, formation and resorption and length of bone in a long-term experiment on intact, ovariectomized and estrogen-treated/substituted rats was studied by using multiple linear regression analysis. The study comprised intact rats killed at 2, 6, 9, 12, 15, and 24 months of age, rats ovariectomized 6 months old and killed at 9, 12, 15, and 24 months of age, and intact and ovariectomized rats treated with a low dose of estrogen for 8 months before they were killed at 24 months of age. Serum IGF-I, bone length and total, subperiosteal and subendocortical bone mass in mid-diaphyseal cross sections of the femur were determined. Changes in the latter two variables, respectively, represent the net result of subperiosteal bone formation and subendocortical bone resorption. Multiple linear regression analysis showed that IGF-I was a positive determinant of cortical bone mass and subperiosteal bone formation. In aged rats, IGF-I was also a positive determinant of bone length, whereas IGF-I was not found to be a determinant of subendocortical bone resorption. The analyses showed that long-term treatment of aged rats with a low dose of estrogen had a dual effect on cortical bone by inhibiting subperiosteal formation and subendocortical resorption. The results revealed a relationship between endogenous circulating IGF-I and local anabolic actions of the growth factor in bones. Thus, IGF-I may be a valuable serum marker of cortical bone formation and length of long bones when considering estrogen-depleted and estrogen-treated rats.

Animals↗

Effect of different dispersing agents on the characteristics of Eudragit microspheres prepared by a solvent evaporation method.

Eudragit RS microspheres containing verapamil HCl for oral use were prepared using three different dispersing agents: aluminium tristearate, magnesium stearate and sucrose stearate, by a solvent evaporation method. The effects of the type and concentration of the dispersing agents and the inner phase polymer concentration on the size and T63.2%, (the time at which 63.2% of the drug is released) of microspheres were determined by multiple linear regression analysis. The morphology of microspheres was characterized by scanning electron microscopy. The surface of microspheres prepared with sucrose stearate was smoother and non-porous and the drug release from these microspheres was the fastest. When aluminium tristearate or magnesium stearate were used as dispersing agents, the particle size of microspheres became smaller. Increasing amounts of these two dispersing agents led to the accumulation of their free particles onto the surfaces of the microspheres. The drug release from the microspheres was slower than that of the microspheres from sucrose stearate depending on their hydrophobic structures. According to the results of the multiple linear regression analysis among the dispersing agents used, aluminium tristearate showed the best correlation between the examined input (dispersing agent and polymer concentrations) and output (T63.2%. and particle size) variables.

Acrylic Resins↗

Comparison of two quality-of-life instruments for cancer patients: the functional assessment of cancer therapy-general and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30.

PURPOSE: To compare two quality-of-life (QOL) questionnaires for cancer patients, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (EORTC QLQ-C30) and the Functional Assessment of Cancer Therapy-General (Fact-G), on the basis of empirical data. PATIENTS AND METHODS: Two hundred forty-four patients with a diagnosis of breast cancer or Hodgkin's disease completed both the EORTC QLQ-C30 and the FACT-G (German language version) during the same session. Questionnaire data were analyzed on a subscale basis using correlation analysis, canonical correlation, and multiple linear regression. RESULTS: Correlations between corresponding subscales of the FACT-G and the EORTC QLQ-C30 ranged from r =.14 for the social domain (very poor agreement) to r =.66 for the physical domain (good agreement), with r values for the other domains lying between these extremes. Canonical correlation analysis for the two sets of subscales revealed that overall agreement between the two instruments was only moderate (first canonical correlation coefficient r =.85, but overall redundancy less than 40%). Of the five FACT-G subscales, only one, physical well-being, was well represented by the EORTC QLQ-C30 subscales (multiple linear regression, R(2) =.67). Only three of eight EORTC QLQ-C30 subscales (physical functioning, global QOL, general symptoms) were represented fairly well by FACT-G subscales (R(2) =.43 to.60). The lowest R(2) values (<.15; ie, virtually no representation by the other instrument) were found for the FACT-G social well-being and relation with doctors and EORTC QLQ-C30 cognitive functioning subscales. CONCLUSION: For the sample investigated, the EORTC QLQ-C30 and the FACT-G were found to measure markedly different aspects of QOL, despite considerable overlap. Replicability provided, this implies that neither of the two QOL instruments can be replaced by the other and that a direct comparison of results obtained with the two instruments is not possible.

Adult↗

Impact of nocturia on symptom-specific quality of life among community-dwelling adults aged 40 years and older.

OBJECTIVES: To evaluate factors predicting the effect of nocturia in a community-based cohort of adults using a nocturia-specific quality-of-life (N-QOL) questionnaire. METHODS: From October 2004 to February 2005, adults aged 40 years old or older living in Matsu, Taiwan and reporting nocturia of one episode or more per night were interviewed with a 12-item N-QOL questionnaire consisting of Sleep/Energy and Bother/Concern subscales. Univariate analyses were used to analyze the effects of demographic characteristics, frequency and duration of nocturia, and sleeping characteristics on the N-QOL score. Multiple linear regression analysis was used to identify factors predicting the N-QOL score. RESULTS: A total of 663 adults completed this study (mean age 59.4 years). The average N-QOL scores (a lower score indicates worse QOL) were 91.4 +/- 11.2, 83.7 +/- 13.2, 77.6 +/- 16.8, and 67.6 +/- 21.2 for nocturia episodes of 1, 2, 3, and 4 or more per night, respectively (P < 0.001). Men reported significantly lower N-QOL (85.6 +/- 15.1 versus 88.9 +/- 13.1, P = 0.003) and Bother/Concern subscale scores (42.0 +/- 8.4 versus 44.0 +/- 7.4, P < 0.001), but not Energy/Sleep subscale scores (43.6 +/- 7.8 versus 44.4 +/- 7.3, P = 0.158) than women. On multiple linear regression analysis, increasing nocturia episodes (regression coefficient -6.2, 95% confidence interval -7.4 to -5.0), male sex (regression coefficient -3.5, 95% confidence interval -5.4 to -1.5), and degree of sleeping disturbance after nocturia (regression coefficient -4.5, 95% confidence interval -5.6 to -3.4) independently predicted a significantly lower N-QOL score. CONCLUSIONS: The results of our study have confirmed that nocturia has a more significant QOL impact when the patient has two or more episodes per night. Moreover, men experienced a greater impact from nocturia than women, particularly in the Bother/Concern domain.

Adult↗

Iron overload in patients with chronic hepatitis C virus infection: clinical and histological study.

BACKGROUND: Recently it has been found that iron is an important element in the natural history of hepatitis C. Serum markers of iron stores are frequently increased in chronic hepatitis C virus (HCV)-infected carriers but the real impact of the hepatic iron overload is poorly understood. The purpose of the present paper was to determine the prevalence of iron overload and to study the relationship between hepatic iron concentration (HIC) and clinical, biochemical and histological characteristics in chronic HCV-infected carriers. METHODS: Patients presenting with anti-HCV and HCV-RNA were included. Hepatic iron concentration was determined in liver tissue by atomic absorption spectrophotometry. The association between HIC and age, gender, risk factor of transmission, duration of infection, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, iron and serum ferritin, transferrin saturation, HCV-RNA level, grading of inflammatory activity, staging of fibrosis, hepatic steatosis, and stainable iron was analyzed. Statistical analysis included the Mann-Whitney test and a multiple linear regression model. RESULTS: Ninety-six patients (58% male) with a mean age of 44 +/- 10 years were studied. Serum iron, ferritin and transferrin saturation were elevated in 28%, 27% and 12.5% of patients, respectively. Stainable iron was detected in few patients (15.6%). Higher grades of stainable iron (2 and 3) were observed in only 7%. The HIC (>30 mmol/g dry weight) was elevated in five patients (5%). Neither grading nor staging were related to HIC. Higher HIC were observed in male patients (P < 0.001), in patients with elevated serum ferritin (P = 0.001) and in patients with stainable iron (grades 2 and 3; P = 0.001). Multiple linear regression analysis showed that only stainable iron was independently correlated with HIC (P = 0.003). CONCLUSIONS: Iron overload in chronically HCV-infected patients was uncommon and hepatic iron content seemed not to be related to the liver damage process. In the eventuality of iron overload, histochemical liver iron is a useful marker to estimate HIC.

Adult↗

Body composition in hemodialysis patients--is it different from that of normal subjects?

OBJECTIVE: Body composition assessment is an important method of evaluating nutritional and metabolic status in hemodialysis patients. PATIENTS AND METHODS: To assess the body composition of hemodialysis patients, we used dual-energy X ray absorptiometry to test 40 stable chronic hemodialysis patients and 40 normal subjects. The patients were from 38 to 70 years old, and all without diabetic mellitus. Comparing with the hemodialysis patients, the normal subjects were selected on a one-to-one base with the same sex and about the same age, body weight and height. RESULTS: The lean body mass/body weight (LBM/BW) ratio had no significant statistical difference between hemodialysis patients and normal subjects in this study (63.02 +/- 8.42% vs 64.80 +/- 7.92%, p =0.3308). The male LBM/BW ratio was higher than that of the female (71.07 +/- 4.63% vs 59.30 +/- 6.35%, p < 0.0001). According to the multiple linear regression analyses, the LBM of hemodialysis patients had positive correlation with gender (p < 0.0001), height (p = 0.0360) and weight (p < 0.0001). The total bone mineral density (BMD) of hemodialysis patients was found to be lower than that of the normal subjects (0.90 +/- 0.10 g/cm vs 0.97 +/- 0.08 g/cm, p = 0.0092). The BMD had been found to be low in the hemodialysis patients with serum intact parathyroid hormone (iPTH) > 1,700 pg/ml. The BMD had negative correlation with age in the female hemodialysis patients (r = 0.63, p = 0.0009), but no correlation in the male hemodialysis patients and in the female or male normal subjects. With the multiple linear regression analyses, the BMD of hemodialysis patients had positive correlation with weight (p = 0.0329) and negative correlation with age (p = 0.0183) and serum iPTH (p = 0.0231). CONCLUSION: We concluded that: the LBM/BW ratio of hemodialysis patients was not different from that of normal subjects. Severe secondary hyperparathyroidism hemodialysis patients had low BMD. The BMD had negative correlation with age in the female hemodialysis patients.

Adult↗

Specificity of release of biogenic amines from isolated rat brain tissue as a function of the meta substituent of N-ethylamphetamine derivatives.

The actions of several meta-substituted N-ethylamphetamines on the release, uptake and catabolism of biogenic amines were investigated in vitro in two regions of rat brain. Each of the compounds released 3H-norepinephrine from chopped cerebral cortex, and 3H-dopamine and 3H-5-hydroxytryptamine from chopped corpus striatum. Stepwise multiple linear regression analyses indicated that the potencies (EC50 values) with which the compounds released 3H-norepinephrine were inversely related (r = 0.94) to the size of the meta substituent. Addition of substituent lipophilic or electronic effects to the regression equation did not greatly improve the correlation. However, the maximal release of 3H-norepinephrine produced by these compounds was directly related only to substituent lipophilic effects (r = 0.95). The potencies and maxima with which the compounds released 3H-dopamine or 3H-5-hydroxytryptamine and the potencies with which the compounds inhibited the uptake of the 3H-amines were not correlated with substituent size, lipophilicity or electronegativity. Variations in meta substituent also altered the degree to which the release 3H-amines were metabolized by monoamine oxidase. Multiple linear regression analyses indicated that for each of the 3H-amines, the maximal percent increase in 3H-deaminated metabolites produced by the drugs was directly correlated only with substituent size (r = 0.85, 0.89 and 0.95 for 3H-norepinephrine, 3H-dopamine and 3H-5-hydroxytryptamine, respectively). Comparisons among the potencies with which compounds released the various 3H-amines indicated that, in general, as substituent size increased, the compounds became relatively less potent in releasing 3H-catecholamines and relatively more potent in releasing 3H-5-hydroxytryptamine. Thus, these studies indicate that variations in the meta substituent group of N-ethylamphetamine derivatives determine the affinity of the derivatives for norepinephrine nerve endings and the relative affinities of the derivatives for norepinephrine, dopamine and 5-hydroxytryptamine nerve endings.

Amphetamines↗

Predicting isolated postchallenge hyperglycaemia: a new approach; Tehran Lipid and Glucose Study (TLGS).

AIMS: To determine factors predicting isolated postchallenge hyperglycaemia (IPH) defined as fasting plasma glucose (FPG) < 7.0 mmol/l and 2-h plasma glucose (2-hPG) >or= 11.1 mmol/l after an oral glucose tolerance test (OGTT) and factors influencing the value of 2-hPG in a population-based study. MATERIALS AND METHODS: From 15,005 participants in the Tehran Lipid and Glucose Study (TLGS), we analysed the results of OGTTs in 5386 individuals (2909 women and 2437 men) aged >or= 20 years, free of known diabetes and any other disorders influencing glucose metabolism. Logistic and multiple linear regression models were developed to predict IPH and the 2-hPG, respectively. RESULTS: The overall prevalence of non-diabetic subjects, IPH and undiagnosed Type 2 diabetes mellitus (FPG >or= 7.0 mmol/l) were 94.5% (n = 5088), 2.5% (n = 133) and 3.1% (n = 165), respectively. Of subjects with IPH, 29.3% (n = 39) had FPG levels < 5.6 mmol/l. Factors associated with IPH were FPG (mmol/l) [odds ratio (OR) 11.05, 95% confidence interval (CI) 7.9, 15.4], age >or= 40 years (OR 2.0, 95% CI 1.3, 3.2), abnormal waist circumference (OR 2.1, 95% CI 1.4, 3.1) and serum triglycerides >or= 1.7 mmol/l (OR 2.0, 95% CI 1.3, 3.1). In the multiple linear regression model, six explanatory factors (FPG, age, female sex, triglycerides, systolic blood pressure, waist circumference) were positively related to 2-hPG. CONCLUSIONS: The model could predict 47.7% of total variance of 2-hPG. Based on our results in this Iranian population, OGTT can be recommended in subjects with FPG < 7.0 mmol/l in the presence of abnormal waist circumference and triglycerides, age >or= 40 years and in particular when FPG is close to 7.0 mmol/l.

Adult↗

Relationship between salivary histatin 5 levels and Candida CFU counts in healthy elderly.

OBJECTIVES: Few epidemiological studies have confirmed the antifungal activity of histatin 5 in saliva against Candida species. The purpose of this study was to examine the relationship between concentrations of histatin 5 and the number of cultivable Candida in saliva samples from elderly. METHODS: Whole saliva samples were obtained from 124 elderly people, 65 years or older, living in a rural community. The concentrations of histatin 5 in saliva samples were determined by the enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody. Total colony-forming units (CFUs) were counted on a selective medium for Candida. Multiple linear regression analysis was performed to determine the independent contribution of explanatory variables to Candida CFUs using age, sex, histatin 5 concentration and type of denture prosthesis as independent variables. RESULTS: Saliva samples from 104 subjects (84%) were candidal colony-positive. The youngest group (65-69 years old) showed significantly smaller Candida CFU counts than those in the older group. The mean Candida CFU count of denture wearers was significantly higher than that of non-denture wearers. Significantly negative associations were found between Candida CFU counts and histatin 5 level in the oldest group (p < 0.05) and in the full-denture wearers (p < 0.01). Multiple linear regression analysis revealed that Candida CFU counts were mostly associated with type of dentures, followed by histatin 5 concentration. CONCLUSION: Possible activity of histatin 5 against Candida in whole saliva of elderly people was epidemiologically confirmed. The area covered by the prostheses was a strong factor associated with the Candida CFU count.

Age Factors↗

Is the metabolic syndrome an independent risk factor for erectile dysfunction?

PURPOSE: We determined the role of the metabolic syndrome as an independent risk factor for erectile dysfunction. MATERIALS AND METHODS: Men participating in a health screening project completed the International Index of Erectile Function-5. The metabolic syndrome was defined according to the 2005 International Diabetes Federation consensus definition. Multiple linear regression, ANOVA and chi-square tests were used to investigate the impact of the metabolic syndrome on erectile dysfunction. RESULTS: A total of 2,371 men with a mean age of 46.1 years (SD 9.9, range 30 to 69) were analyzed. Of the men 33.4% (652) had no erectile dysfunction (International Index of Erectile Function-5 score 22 to 25), 59.7% (1,166) had mild erectile dysfunction (International Index of Erectile Function-5 score 17 to 21) and 6.9% (134) had moderate to severe erectile dysfunction (International Index of Erectile Function-5 score 5 to 16). The metabolic syndrome was present in 33.8% (794). In a multiple linear regression analysis an increased waist-to-hip ratio (p = 0.01) and metabolic syndrome (p = 0.01) turned out to be independently associated with a decreased International Index of Erectile Function-5 score. When stratified according to age, the metabolic syndrome was correlated to erectile dysfunction only in men 50 years old or older with an increase of severe erectile dysfunction by 48% (p = 0.01). CONCLUSIONS: The metabolic syndrome and an increased waist-to-hip ratio are independently associated with a decreased International Index of Erectile Function-5 score. The metabolic syndrome in men older than 50 years is significantly associated with a higher proportion of moderate to severe erectile dysfunction.

Adult↗

Homocysteine level and coronary artery disease.

Atherosclerosis, and its most common manifestation, coronary artery disease (CAD), are rather common causes of morbidity and mortality worldwide. Recognition of its various risk factors is important to planning effective preventive measures. After the homocysteine theory was presented in 1969, attention has been directed toward the serum homocysteine level as a coronary artery disease risk factor. The authors aimed to assess the relationship between hyperhomocysteinemia and CAD in an Iranian population. In a case control study, 197 individuals (male: 123 [62.4%]) who were scheduled for coronary angiography were selected. Venous samples were taken from the patients in fasting state before angiography. Data about age, sex, risk factors (eg, hypertension, diabetes, smoking, hyperlipidemia, obesity) were obtained from prepared questionnaires. Homocysteine levels in patients were measured by ELISA method. A homocysteine level above 15 mumol/liter was considered high. Angiography reports and homocysteine levels were analyzed by independent sample t test, one-way ANOVA, multiple linear regression, and stratified analysis. In comparison with the patients with normal angiography reports (32.5%), patients with abnormal angiography reports (67.5%) had increased levels of homocysteine (p = 0.001). About 28.1% of patients with normal angiography reports had hyperhomocysteinemia. After further evaluation, linear correlations were detected between the numbers of involved vessels and homocysteine level (p = 0.000). Multiple linear regression analysis of data detected that in individuals without any risk factors, the relationship was stronger and more meaningful (p = 0.000). These data show that hyperhomocysteinemia is related to CAD as an independent risk factor. In individuals without any risk factors a linear correlation between homocysteine level and numbers of coronary artery involvement was present. If this equation is confirmed prospectively in other studies, the level of plasma homocysteine may he used as a noninvasive way of predicting the number of diseased coronary arteries.

Adult↗

The needs of patients with arthritis: the patient's perspective.

OBJECTIVE: To identify concerns and learning interests of patients with arthritis. METHODS: A questionnaire was developed, pilot tested, and then used to evaluate 197 patients with arthritis, including osteoarthritis (OA) (n = 41), rheumatoid arthritis (RA) (n = 57), back disease (n = 55), systemic lupus erythematosus (n = 27), and systemic sclerosis (SSc) (n = 17). Twenty concerns and 12 learning interests were rated. Questionnaires were also administered to assess physical disability (Health Assessment Questionnaire), psychological disability (Arthritis Impact Measurement Scales 2), and pain (visual analog scale). Participants addressed accessibility of health services, satisfaction with their physician, psychosocial needs, use of self-help groups, and behavioral strategies used to assist coping. Patients with RA, OA, and back disease, at both a community and a hospital center, were tested to assess whether concerns and learning interests differed based on site of treatment. Analytic methods included analysis of variance, factor analysis, and multiple linear regression. RESULTS: There were no differences in concerns or learning interests based on treatment site. Between diagnostic groups, patients with SSc were more interested in learning about self-help groups. The most frequently reported concern was worsening of the illness. The majority of respondents were interested in learning more about topics that were illness specific. The physician was chosen as the preferred source of information, and the preferred format was in writing. On factor analysis, the 20 concerns were reduced to 5 factors: psychological, coping, medication, social, and financial. Three factors were identified for learning interests: the illness, traditional health management topics, and nontraditional health management topics. Stepwise multiple linear regression revealed predictors for the 5 concern and 3 learning interest factors. The concerns were best predicted by self-reported disease severity, physical disability, and psychological distress, while learning interests were best predicted by self-reported disease severity, pain, and self-help group membership. CONCLUSION: Concerns and learning interests of persons with arthritis did not differ based on the center of treatment or the diagnosis, but can be predicted by the level of pain and simple measures of disability. Better understanding of the relationship between health status and patient-perceived needs will result in improved patient-centered care.

Activities of Daily Living↗

Adiponectin is independently associated with insulin sensitivity in women with polycystic ovary syndrome.

OBJECTIVE: The polycystic ovary syndrome (PCOS) is associated with obesity and insulin resistance predisposing to diabetes mellitus type 2 and atherosclerosis. Adiponectin is a recently discovered adipocytokine with insulin-sensitizing and putative antiatherosclerotic properties. The aim of the study was to elucidate determinants of circulating adiponectin levels and to investigate the potential role of adiponectin in insulin resistance in PCOS women. PATIENTS AND MEASUREMENTS: Plasma adiponectin and parameters of obesity, insulin resistance and hyperandrogenism were measured In 62 women with PCOS and in 35 healthy female controls. RESULTS: Both in PCOS and controls, adiponectin levels were lower in overweight or obese women than in normal-weight women, without any difference between PCOS and controls after adjustment for body mass index (BMI). In PCOS and in controls there was a significant correlation of adiponectin with BMI (r = -0.516, P < 0.001), fasting insulin (r = -0.404, P < 0.001), homeostasis model sensitivity (HOMA %S) (r = -0.424, P < 0.001) and testosterone (r = -0.279, P < 0.01), but no correlation with androstenedione (r = -0.112, P = 0.325), 17-OH-progesterone (r =-0.031, P = 0.784) or the LH/FSH ratio (r =-0.033, P = 0.753). Multiple linear regression analysis revealed that BMI and HOMA %S but not testosterone were independently associated with adiponectin plasma levels, explaining 16% (BMI) and 13% (HOMA %S) of the variability of adiponectin, respectively. In PCOS patients insulin sensitivity, as indicated by continuous infusion of glucose with model assessment (CIGMA %S) was significantly correlated with adiponectin (r = 0.55; P < 0.001), BMI (r =-0.575; P < 0.001), waist-to-hip ratio (WHR) (r =-0.48; P = 0.001), body fat mass assessed by dual-energy X-ray-absorptiometry (DEXA) [Dexa-fat (total) (r = -0.61; P < 0.001) and Dexa-fat (trunk) (r = -0.59; P < 0.001)] and with testosterone (r = -0.42; P = 0.001). Multiple linear regression analysis demonstrated that markers of obesity such as BMI, total or truncal fat mass, age and adiponectin were independently associated with CIGMA %S, and that circulating adiponectin accounted for about 18% of the degree of insulin resistance in PCOS. By contrast, testosterone was not a significant factor, suggesting that PCOS per se did not affect insulin sensitivity independent from obesity, age and adiponectin. Metformin treatment for 6 months in insulin-resistant PCOS women (n = 9) had no effect on plasma adiponectin (P = 0.59) despite significant loss of weight and fat mass and improvement in hyperandrogenaemia. CONCLUSIONS: PCOS per se is not associated with decreased levels of plasma adiponectin. However, circulating adiponectin is independently associated with the degree of insulin resistance in PCOS women and may contribute to the development and/or maintenance of insulin resistance independent from adiposity.

Adiponectin↗

Monitoring of intrathoracic volemia and cardiac output in critically ill children.

AIM: Hemodynamic monitoring is an important step in the management of critically ill children despite the difficulty in measuring preload indices continuously. The aim of the study was to analyze cardiac output parameters and preload indices after acute changes in mean airway pressure and volemia. METHODS: Twenty-three children treated at our unit were enrolled in a prospective non randomized cohort study. Respiration was supported by controlled mechanical ventilation with positive expiratory-end pressure (PEEP), peak inspiratory pressure <20 cm H(2)O and mean airway pressure <10 cm H(2)O, and hemodynamic monitoring using the PiCCO system. Hemodynamic parameters were measured at T0 (base line), T(1) (after an increase in PEEP of 5 cm H(2)O for 10 min), and T(2) (after fluid challenge). The statistical analysis (BMPD New System software package) comprised comparison of changes at T(0) vs T(1), T(1) vs T(2) and T(0) vs T(2), construction of 3 correlation matrices and multiple linear regression analysis. RESULTS: Sixty-nine hemodynamic parameters were measured in the 23 patients. A comparison between T(0) and T(1) showed no significant changes; differences between T(0) and T(2) were found for cardiac index (CI), (p=0.003); between T(0) and T(2) significant differences were found for CI (p=0.0015), intrathoracic blood volume index (ITBVI) (p=0.04) and stroke volume index (SVI) (p=0.06). The analysis of the correlation matrices yielded ITBVI with CI (p=0.0006), ITBVI with SVI (p=1 x 10(-5)), CI with SVI (p=0.002); a significant correlation between CI and extravascular lung water index (EVLWI) was found only at T(1). Multiple linear regression analysis showed that ITBVI and SVI were predictive for variance of CI at each time point. CONCLUSION: ITBVI measured by a volumetric monitoring system such as the PiCCO may be considered a sensitive preload indicator also in critically ill children.

Adolescent↗

[Drug costs in reformed primary care: effect of training activities on drug savings].

OBJECTIVE: To determine the influence on drug expenditures by reformed primary care services of factors relative to the personal characteristics of prescribers, their training and training activities, their professional practice, organizational factors, and characteristics of the patient population attended. MATERIAL AND METHODS: This cross-sectional, observational study was carried out in the Sabadell Primary Care Directorate, Vallés Occidental region (Barcelona, Spain). This primary care directorate is responsible for the health-care needs of 9 municipalities (with a total population of 254,971 inhabitants). It has 12 Basic Health Areas, 8 of which have Primary Care Teams. The area of study included these 8 primary care teams and the unit of analysis contained 68 of 80 staff physicians. The quantitative prescription indicators (dependent variables) were: total annual drug expenditure, drug expenditure per user and year (users being understood as patients with an open medical record), drug expenditure per visit and year, mean cost per prescription, prescription/user ratio, and prescription/visit ratio. Descriptive, bivariate, and multiple linear regression analyses were made. RESULTS: The variables predictive of greater drug expenditures were: patient age, visits, frequentation, referrals to primary-care specialists, urban municipality, physicians with primary care and hospital practice, time on staff, and physician age. Participation in training activities was predictive of drug savings, with each primary-care training session attended producing a mean annual savings in drug expenditures of 50 ptas and 15 ptas per user and visit, respectively. Every hour dedicated to training in the community produced a savings of almost 60,000 ptas in annual drug expenditures. For each rational-drug-use session, the mean price of prescriptions decreased by 52 ptas. In the multiple linear regression models obtained, the variables that most frequently helped to explain variations between prescribers in relation to drug expenditures were: patient age, urban municipality, and primary-care-team training activities (as factors in drug savings). CONCLUSIONS: This study confirmed that patient age, frequentation, and type of municipality increased drug expenditures. Urban municipalities, as opposed to rural or semirural municipalities, were associated with a significantly greater expense, in contrast with prevailing opinion. Our results suggested that drug expenditures increase with referrals to specialists. An interesting new finding is that physicians with simultaneous primary care and hospital practice generated more drug expenditures. Finally, we emphasize the importance of training the primary-care team in promoting drug savings (four models: drug expenditures by users, drug expenditures per visit, prescriptions per user, and prescriptions per visit), rational-drug-use activities, which tended to reduce the mean cost of prescriptions, and community training activities, which clearly reduced annual total drug expenditures.

Aged↗

[Multiple analysis on the gastric impetus associated factors in patients with liver cirrhosis].

OBJECTIVE: To investigate mechanism and relation of some disorder motive forces of digest system in patients with liver cirrhosis. METHODS: Plasma vasoactive intestinal peptide (VIP), gastrin and motilin (MTL), electrogastrogram (EGG) and pH value of gastric juice in 24 hours; gastric elimination time by isotope. All above factors have been determined in patients with liver cirrhosis and analyzed with multiple linear regressions. While a group of normal cases has been observed as control. RESULTS: Compared to the control group, higher level of VIP and Gastrin and lower MTL down were observed in liver cirrhosis group (Plasma VIP, Gastrin and MTL are 14.8+/-4.8, 58.6+/-29.8 and 360+/-54.2 separately, t=5.181, 0.05, t=3.871, 0.01 and t=5.529, 0.05 separately). The EGG dominant frequency (DF) and dominant power (DP) decreased around diet; normal slow wave number (N%) decreased and gastric excretion time prolonged, lower bradygastrias (B%) and pH value of 24 hours gastric juice denoted the incline of return movement, there are remarked different with 0.05 or 0.01 separately. Throughout analyzing these factors with multiple linear regressions, there are remarkable relationship between liver cirrhosis and pH value of gastric juice; gastrointestinal hormone and EGG with 0.05 or 0.01. CONCLUSION: (1) There are remarkable gastro esophageal function abnormal which has been conveyed by disorder gastric electric physiology and gastric elimination time in patients with liver cirrhosis. It is suggested that unusual gastrointestinal hormone played an important role during these abnormal process. (2) There is remarkable changing of pH value of 24 hours gastric juice denoted the opposite movement of gastroduodenal juice in patients with liver cirrhosis.

Female↗

All cause mortality and its determinants in middle aged men in Finland, The Netherlands, and Italy in a 25 year follow up.

STUDY OBJECTIVE: The aims were (1) to compare all cause mortality in population samples of different cultures; and (2) to cross predict fatal event by risk functions involving risk factors usually measured in cardiovascular epidemiology. DESIGN: The study was a 25 year prospective cohort study. The prediction of all cause mortality was made using the multiple logistic equation as a function of 12 risk factors; the prediction of months lived after entry examination was made by the multiple linear regression using the same factors. POPULATION SAMPLES: There were five cohorts of men aged 40-59 years, from Finland (two cohorts, 1677 men), from The Netherlands (one cohort, 878 men), and from Italy (two cohorts, 1712 men). SETTING: The Finnish cohorts came from geographically defined rural areas, the Dutch cohort from a small town in central Holland, and the Italian cohorts from rural villages in northern and central Italy. MEASUREMENTS AND MAIN RESULTS: All cause mortality was highest in Finland (557 per 1000), and lower in The Netherlands (477) and in Italy (475). The solutions of the multiple logistic function showed the significant and almost universal predictive role of certain factors, with rare exceptions. These were age, blood pressure, cigarette smoking, and arm circumference (the latter with a negative relationship). Similar results were obtained when solving a multiple linear regression equation predicting the number of months lived after entry examination as a function of the same factors. The prediction of fatal events in each country, using the risk functions of the others, produced limited errors, the smallest one being -2% and the largest +11%. When solving the logistic model in the pool of all the cohorts with the addition of dummy variables for the identification of nationality, it also appeared that only a small part of the mortality differences between countries is not explained by 12 available risk factors. CONCLUSIONS: A small set of risk factors seems to explain the intercohort differences of 25 year all cause mortality in population samples of three rather different cultures.

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Influence of age, sex, folate and vitamin B12 status on plasma homocysteine in Saudis.

OBJECTIVE: To evaluate the reference intervals for fasting total plasma homocysteine concentrations in Saudi healthy males and females in relation to age, sex and the nutritional status of folate and vitamin B12. METHODS: A prospective study was conducted on randomly selected Saudi healthy males (n=642) and females (n=784) living in the Jeddah area, Kingdom of Saudi Arabia. Plasma homocysteine together with serum folate and plasma vitamin B12 concentrations were determined. Analysis of variance was used to examine differences among various groups according to age, sex or folate, or both or vitamin B12 status for different variables. Correlations were carried out using multiple linear regression analysis. RESULTS: Reference intervals for plasma homocysteine concentrations in Saudi healthy males and females (age 20 -69 years) was documented. The age-adjusted geometric mean of plasma homocysteine concentration was significantly greater in males (9.91 micromol/L) than in females (8.08 micromol/L) (P<0.0001). In both males and females, values for serum folate and plasma vitamin B12 concentrations significantly and negatively correlated with plasma homocysteine concentrations (P<0.000). Serum total cholesterol showed significant positive correlations with plasma homocysteine in both males (r=0.448, P<0.000) and females (r=0.313; P < 0.000). Diastolic (r= 0.182; P<0.001) and systolic (r=0.309; P < 0.000) blood pressure values showed significant positive correlations with plasma homocysteine concentrations in females only. Stepwise multiple linear regression analysis showed that in both males and females, age, sex, serum folate, and waist-to-hip ratio and plasma vitamin B12 were significant determinants of plasma homocysteine concentrations. CONCLUSION: The first data on plasma homocysteine concentrations in Saudi healthy males and females are reported. Age and sex differences were confirmed and a significant inverse relationship between plasma homocysteine concentrations and that of serum folate and plasma vitamin B12 was observed. Various independent variables including age, sex, serum folate, waist-to-hip ratio and plasma vitamin B12 contributed to the changes in plasma homocysteine. Plasma homocysteine concentrations should be evaluated in patients at risk for cardiovascular and other related diseases in the Saudi population.

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