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PubMed1990

Prediction of length of hospitalization of adolescent psychiatric inpatients utilizing the Pd Scale of the MMPI and demographic data.

This study attempts to determine whether selected personality and demographic information can be utilized to predict the length of stay of adolescents in an inpatient therapeutic program. Predictor variables included scores on the five Harris-Lingoes Psychopathic-Deviate subscales of the Minnesota Multiphasic Personality Inventory (MMPI), Wechsler Intelligence Scale for Children-Revised (WISC-R scores, and sex, age, parent, and sibling information. Data were collected from case files of 140 adolescents, ages 12 to 18 years, who had been admitted to a state hospital from 1979 to 1985. Each of these adolescents had obtained a score of 70 or above on the Psychopathic-Deviate (Pd) Scale of the MMPI. A preliminary correlational investigation of the data was conducted, followed by stepwise regression analysis. Regression analysis revealed that only sex and the presence of an older sister(s) were significant in prediction of length of stay of inpatient adolescents with elevated Pd scores.

Adolescent↗

PubMed1983

Sex-related differences in the concentrations of apolipoprotein E in human blood plasma and plasma lipoproteins.

Apolipoprotein E (apoE) and lipoprotein cholesterol and triglycerides were measured in blood serum of 272 persons randomly selected from a large industrial population in northern California. Serum apoE level increased linearly by 0.013 mg/dl with each 1 mg/dl increase in very low density lipoprotein (VLDL) triglycerides. This estimate was independent of sex and the use of sex hormones by women. Compositional studies of isolated apoVLDL in 156 hypertriglyceridemic men and 162 normotriglyceridemic persons of both sexes from the same population also indicated that the content of apoE was independent of VLDL level, sex, and hormone use. The estimate of the relationship between serum apoE and VLDL-triglycerides derived from these compositional studies was comparable to that derived by regression analysis. Regression analysis also indicated that only 10-20% of the apoE in the serum of the average person is in the VLDL fraction. Serum apoE levels were 1.4 mg/dl higher in women than in men with the same VLDL-triglyceride level and 1.8 mg/dl lower in women using contraceptive drugs than in nonusers of like age and VLDL-triglyceride level.

Adult↗

PubMed2003

Determinants of subjective quality of life in post acute patients with schizophrenia.

Although Quality of Life (QoL) is of growing interest in schizophrenia research, little is known about putative causal determinants of this multidimensional construct. The present study explored the utility of objective indicators, psychopathological symptoms and psychosocial concepts drawn from empirical findings in community samples and the vulnerability-stress-coping model of schizophrenia for predicting general subjective QoL in post acute patients with schizophrenia. The analyses were based on cross-sectional data from 66 post acute patients with schizophrenia. The relationships between QoL and possible determinants were investigated using correlational analysis, regression analysis and structural equation techniques. As a result no significant relationships between objective indicators and general QoL were found. The strongest significant determinants were depressive symptoms and the psychosocial concepts of negative coping, perceived social support and self-efficacy. The empirical causal modelling results indicated that depression led to a direct negative impact upon QoL, whereas the other determinants had direct negative or positive effects on depression and affected QoL indirectly. One could conclude that to enhance patients' QoL, improvements in depressive symptoms, negative coping style, social support and self-efficacy seem to be most effective.

Activities of Daily Living↗

PubMed2005

PSA nadir predicts biochemical and distant failures after external beam radiotherapy for prostate cancer: a multi-institutional analysis.

PURPOSE: To determine the significance of prostate-specific antigen (PSA) nadir (nPSA) and the time to nPSA (T(nPSA)) in predicting biochemical or clinical disease-free survival (PSA-DFS) and distant metastasis-free survival (DMFS) in patients treated with definitive external beam radiotherapy (RT) for clinical Stage T1b-T2 prostate cancer. METHODS AND MATERIALS: Nine participating institutions submitted data on 4839 patients treated between 1986 and 1995 for Stage T1b-T2cN0-NxM0 prostate cancer. All patients were treated definitively with RT alone to doses > or =60 Gy, without neoadjuvant or planned adjuvant androgen suppression. A total of 4833 patients with a median follow-up of 6.3 years met the criteria for analysis. Two endpoints were considered: (1) PSA-DFS, defined as freedom from PSA failure (American Society for Therapeutic Radiology and Oncology definition), initiation of androgen suppression after completion of RT, or documented local or distant failure; and (2) DMFS, defined as freedom from clinically apparent distant failure. In patients with failure, nPSA was defined as the lowest PSA measurement before any failure. In patients without failure, nPSA was the lowest PSA measurement during the entire follow-up period. T(nPSA) was calculated from the completion of RT to the nPSA date. RESULTS: A greater nPSA level and shorter T(nPSA) were associated with decreased PSA-DFS and DMFS in all patients and in all risk categories (low [Stage T1b, T1c, or T2a, Gleason score < or =6, and PSA level < or =10 ng/mL], intermediate [Stage T1b, T1c, or T2a, Gleason score < or =6, and PSA level >10 but < or =20 ng/mL, or Stage T2b or T2c, Gleason score < or =6, and PSA level < or =20 ng/mL, or Gleason score 7 and PSA level < or =20 ng/mL], and high [Gleason score 8-10 or PSA level >20 ng/mL]), regardless of RT dose. The 8-year PSA-DFS and DMFS rate for patients with nPSA <0.5 ng/mL was 75% and 97%; nPSA > or =0.5 but <1.0 ng/mL, 52% and 96%; nPSA > or =1.0 but <2.0 ng/mL, 40% and 91%; and nPSA > or =2.0 ng/mL, 17% and 73%, respectively. The 8-year PSA-DFS and DMFS rate for patients with T(nPSA) <6 months was 27% and 66%; T(nPSA) > or =6 but <12 months, 31% and 85%; T(nPSA) > or =12 but <24 months, 42% and 94%; and T(nPSA) > or =24 months, 75% and 99%, respectively. A shorter T(nPSA) was associated with decreased PSA-DFS and DMFS, regardless of the nPSA. Both nPSA and T(nPSA) were significant predictors of PSA-DFS and DMFS in multivariate models incorporating clinical stage, Gleason score, initial PSA level, and RT dose. The significance of nPSA and T(nPSA) was supported by landmark analysis, as well as by analysis of nPSA and T(nPSA) as time-dependent covariates. A dose > or =70 Gy was associated with a lower nPSA level and longer T(nPSA) in all risk categories, and a greater dose was significantly associated with greater PSA-DFS and DMFS in multivariate analysis. Regression analysis confirmed that higher clinical stage, Gleason score, and initial PSA were associated with a greater nPSA level. CONCLUSION: The results of this large, multi-institutional analysis of 4833 patients have provided important evidence that nPSA and T(nPSA) after definitive external beam RT are not only predictive of a predominantly PSA endpoint (PSA-DFS), but are also predictive of distant metastasis in all clinical risk categories. Greater RT doses were associated with lower nPSA, longer T(nPSA), and improved PSA-DFS and DMFS.

Disease-Free Survival↗

PubMedDate not supplied

The effect of body position on bioelectrical resistance in individuals with spinal cord injury.

The purpose of this study was to determine the effect of four different body positions on the resistance of the human body as assessed by Biodynamics Model 310 Body Composition Analyzer in a healthy population (Group A, n = 69) and long-term spinal cord injured (Group B, n = 13). Group A were tested in four body positions: supine, half-lying, standing and sitting in a wheelchair, while Group B were tested in supine and sitting positions. Testing order was randomized. A one-way repeated measures analysis of variance and a paired t-test demonstrated significant differences between position (p < 0.0001, Group A; p < 0.01, Group B respectively). In both groups, the greatest reduction in resistance was demonstrated for the sitting position. These differences were similar for both groups, as demonstrated by covariant analysis. Regression analysis demonstrated that supine resistance can be accurately predicted (R2 = 0.98) from assessments in a wheelchair. Such data transformations may be indicated where supine positioning is problematic or when wheelchair assessment procedures are more appropriate.

Adult↗

PubMed2000

Successful lecturing: a prospective study to validate attributes of the effective medical lecture.

OBJECTIVE: In a study conducted over 3 large symposia on intensive review of internal medicine, we previously assessed the features that were most important to course participants in evaluating the quality of a lecture. In this study, we attempt to validate these observations by assessing prospectively the extent to which ratings of specific lecture features would predict the overall evaluation of lectures. MEASUREMENTS AND MAIN RESULTS: After each lecture, 143 to 355 course participants rated the overall lecture quality of 69 speakers involved in a large symposium on intensive review of internal medicine. In addition, 7 selected participants and the course directors rated specific lecture features and overall quality for each speaker. The relations among the variables were assessed through Pearson correlation coefficients and cluster analysis. Regression analysis was performed to determine which features would predict the overall lecture quality ratings. The features that most highly correlated with ratings of overall lecture quality were the speaker's abilities to identify key points (r =.797) and be engaging (r =.782), the lecture clarity (r =.754), and the slide comprehensibility (r =.691) and format (r =.660). The three lecture features of engaging the audience, lecture clarity, and using a case-based format were identified through regression as the strongest predictors of overall lecture quality ratings (R2 = 0.67, P = 0.0001). CONCLUSIONS: We have identified core lecture features that positively affect the success of the lecture. We believe our findings are useful for lecturers wanting to improve their effectiveness and for educators who design continuing medical education curricula.

Education, Medical, Continuing↗

PubMed1993

Dementia, agitation, and care in the nursing home.

OBJECTIVE: To examine the behavioral and functional problems of the cognitively impaired. DESIGN: A survey of a cohort of residents from six nursing homes. PARTICIPANTS: Subjects were randomly selected based on a minimum age of 70 years and a Resource Utilization Group (RUG) classification of the Physical or Behavioral type. Of those eligible, 44% (n = 366) agreed to participate. The participants and non-participants had similar demographics except for a higher incidence of mental illness in the non-participant group, which did not have a significant impact on agitation. SETTING: Six nursing homes in New York City, three voluntary non-profit and three proprietary. MEASUREMENT: The study used chart review, assessment of residents' cognitive and functional abilities, nursing assistants' ratings of residents' functional abilities, behavioral problems, and the amount of effort required in care, and time-motion observations of staff-resident interactions. RESULTS: Residents' level of cognitive impairment had a significant impact on problem behaviors during ADL tasks, along with supervision required in patient care (P < 0.05). These results were validated by time-motion analysis. Regression analysis revealed that for non-demented subjects, the best indicator of care needs was health status, while for demented residents the best indicator was cognitive status (P < 0.0001). CONCLUSIONS: The care needs of residents with dementia are better estimated by a mental status test for cognitive impairment then by ADL assessment alone. Greater agitation is associated with increasing cognitive impairment. Further, agitation and behavioral problems associated with care result in a need for increased staff supervision.

Activities of Daily Living↗

PubMedDate not supplied

Accuracy and clinical correlates of two different methods for chromogranin A assay in neuroendocrine tumors.

Measurement of chromogranin A (CgA) plays a major role in the management of neuroendocrine tumors (NET); however, reliable assaying of CgA is made difficult by the rapid hydrolysis following its release into the bloodstream. This study was aimed at the assessment of two assays for CgA in NET patients. CgA was measured in 93 patients by means of an enzyme-linked immunosorbent assay (ELISA) and an immunoradiometric assay (IRMA). The specificity and sensitivity of CgA were evaluated in relation to tumor histology. The clinical accuracy of the two assays was evaluated by receiver-operating characteristic (ROC) curve analysis. Regression analysis demonstrated different immunoreactivity for CgA of the antibodies used in the two kits (r = 0.61). The two assays had different accuracy also in classifying patients according to their clinical condition (91% vs 64% specificity and 79% vs 79% sensitivity for the ELISA and IRMA assay, respectively) and tumor histology (81% vs 85% sensitivity for the ELISA and IRMA assays, respectively, in carcinoids; 92% vs 67% sensitivity for the ELISA and IRMA assays, respectively, in pancreatic islet cell tumors). The different clinical accuracy of the two assays was confirmed by the ROC analysis (AUC = 0.90 vs AUC = 0.87 for the ELISA and IRMA assays, respectively). In conclusion, because of the poor standardization of the commercially available measurement tools the clinical accuracy of CgA measurement depends on the assay used. This makes it difficult to compare CgA values measured with different kits and affects the clinical accuracy of the different assays for CgA.

Adolescent↗

PubMed1991

Assessment of body composition of poultry by nuclear magnetic resonance imaging and spectroscopy.

Nuclear magnetic resonance (NMR) imaging and spectroscopy were used to assess body composition of the chicken and turkey poult. The NMR imaging was performed using a clinical, whole-body imaging system operating at 1.5 tesla (T; 63 MHz). Three-dimensional reconstruction of cross-sectional images made along the transaxial plane was used to estimate mass of the Pectoralis muscle of chickens ranging in weight from 140 to 2,760 g. Results indicate that NMR imaging can be used to determine size of the Pectoralis muscle (R2 = .99) in the bird, thus permitting repetitive measurements during the growth and development of the bird. The NMR spectroscopy was performed using an imaging spectrometer operating at 4.7 T (200 MHz). Integral areas of the water and lipid proton peaks of the spectra were compared with the water and lipid content of the whole body as determined by chemical analysis. Regression analysis of measurements made on turkey poults, ranging in weight from 115 to 630 g (n = 6), resulted in R2 values of .94 for NMR water proton peak area and total body water, .93 for NMR lipid proton peak area and total body lipid, and .96 for NMR water proton peak area and total body protein. From NMR spectroscopy of chickens weighing 528 +/- 18 g (n = 6), the relative area of the lipid peak correlated with whole-body lipid (R2 = .97). Thus, whole-body spectroscopy of smaller birds can be used to measure total body water, protein, and lipid content.

Animals↗

PubMed2004

Effect of body mass index on nonalcoholic fatty liver disease in patients undergoing minimally invasive bariatric surgery.

The risk factors for nonalcoholic fatty liver disease in patients undergoing bariatric surgery are under study. We wanted to determine the correlation between nonalcoholic fatty liver disease and patient factors such as obesity and liver function tests. A retrospective analysis was performed on 177 nonalcoholic morbidly obese patients who underwent laparoscopic Roux-en-Y gastric bypass with liver biopsy, to identify risk factors for nonalcoholic fatty liver disease. The histologic grade of liver disease was compared with preoperative body mass index, age, and liver function tests. Simple steatosis and steatohepatitis were present in 90% and 42% of patients, respectively. Elevated transaminase levels were an independent risk for liver disease. Body mass index and liver disease were not correlated with univariate analysis. Regression analysis performed on age, body mass index, and liver disease demonstrated that the risk for liver disease increased with body mass index in the younger (<35 years old) age group and decreased with body mass index in the older (>45 years old) age group. There was a high incidence of steatosis and steatohepatitis in these nonalcoholic bariatric patients, and elevated transaminase level was indicative of disease. Body mass index was a positive risk factor for liver disease in younger patients but a negative risk factor in the older patients.

Adult↗

PubMed1997

Body fat percentage of children varies according to their diet composition.

OBJECTIVE: To ascertain the association between diet composition and body fat percentage in 9- and 10-year-old children. Also, to examine the influence of gender, total energy intake, fitness, physical activity, and parental body mass on the relationship between diet composition and adiposity. DESIGN: Diet composition was assessed using the National Cancer Institute food frequency questionnaire, and adiposity was measured using the average of results determined using two skinfold equations. Fitness levels and physical activity were ascertained using the 1-mile run/walk test and a self-report 15-item scale, respectively. SUBJECTS: A sample of 262 children (162 boys and 100 girls, mean age = 9.8 +/- 0.5 years) participated. STATISTICAL ANALYSIS: Regression analysis was used to determine the extent to which diet composition contributed to adiposity without statistical control for any potentially confounding variables. Partial correlations were calculated to assess the relationship between macronutrient intake and adiposity after potential confounders (gender, total energy intake, physical fitness, and parental body mass) were controlled statistically. RESULTS: Energy intake was positively related to adiposity. Fat intake, calculated as a percentage of total energy, was also positively related to adiposity, before and after control for potential confounding variables. Percentage of energy derived from carbohydrate was inversely related to adiposity, before and after controlling for potential confounders. APPLICATIONS: These findings indicate that the macronutrient intake of children, particularly dietary fat and carbohydrate intake, may play a role in adiposity, independent of the influence of total energy intake, gender, physical fitness, and parental body mass index.

Adipose Tissue↗

PubMed1989

Prediction of arterial oxygen partial pressure from intrapulmonary venous admixture.

A short program was developed to predict the PaO2 at a given FIO2 by using arterial and mixed venous blood gas data obtained at an FIO2 of 1.0. Our program resolves Adair's equation and the shunt equation inversely, on the assumption that intrapulmonary venous admixture and the arteriovenous oxygen content difference remain constant during the study. The study was conducted on 19 patients with respiratory failure who were intubated and mechanically ventilated. According to linear regression analysis, regression coefficients of 0.91 and 0.97 were obtained between the measured PaO2 values and those estimated by the arterial/alveolar oxygen tension ratio (PaO2/PaO2) and our program, respectively (n = 23). The PaO2 values were predicted more accurately by our program than those calculated by PaO2/PaO2. Because our program is simple enough to be carried out with a pocket computer, it may be helpful in a bedside decision of lowering FIO2, especially in patients who require a high FIO2 level to maintain sufficient arterial oxygenation.

Blood Gas Analysis↗

PubMed2000

A robust structure-activity relationship (SAR) model for esters that cause skin irritation in humans.

A structure-activity relationship (SAR) model has been developed to discriminate skin irritant from nonirritant esters. The model is based on the physicochemical properties of 42 esters that were tested in humans for skin irritation. Nineteen physicochemical parameters that represent transport, electronic, and steric properties were calculated for each chemical. Best subsets regression analysis indicated candidate models for further analysis. Regression analyses identified significant models (p < 0.05) that had variables that were also significant (p < 0.05). These candidate models were evaluated using linear discriminant analysis to determine if the irritant esters could be discriminated from nonirritant esters. The stability of the model was evident from the consistency of parameters among ten submodels generated using multiple random sampling of the database. The sensitivity of the ten models, evaluated by "leave-one-out" cross-validation, ranged from 0. 846 to 0.923, with a mean of 0.885 +/- 0.025 (95% CI). The specificity ranged from 0.615 to 0.923, with a mean of 0.738 +/- 0.06 (CI). Compared with nonirritant esters, irritant esters had lower density, lower water solubility, lower sum of partial positive charges, higher Hansen hydrogen bonding parameter, and higher Hansen dispersion parameter. The results indicate that physicochemical features of esters contribute to their ability to cause skin irritation in humans, and that chemical partitioning into the epidermis and intermolecular reactions are likely important components of the response. This model is applicable for prediction of human irritation of esters yet untested.

Chemical Phenomena↗

PubMed2004

Quantitative and qualitative evaluations of fetal lung with MR imaging.

PURPOSE: To measure both volume and signal intensity of the fetal lung at magnetic resonance (MR) imaging and to evaluate the clinical use of this method to predict fetal pulmonary hypoplasia. MATERIALS AND METHODS: A total of 87 fetuses evaluated with MR imaging at 24-39 weeks of gestation were classified into a control group with good respiratory outcome (group A, n = 58) or a poor outcome group with severe respiratory disturbance after birth (group B, n = 29). Planimetric measurement of total lung volume and calculation of the ratio of lung signal intensity to spinal fluid signal intensity (L/SF) were performed on MR images by using region-of-interest analysis. Regression analysis, analysis of covariance, analysis of variance, and receiver operating characteristic (ROC) analysis were performed. RESULTS: The best fit for group A lung volume was represented by the regression line V = (2.41 x G) - 37.6 (r = 0.537, P <.001), in which V is lung volume and G is gestational weeks; that for group B, by V = (0.97 x G) - 14.0 (r = 0.378, P <.05). Results of analysis of covariance with gestational weeks used as a covariate showed a significant difference in lung volume between the two groups (P <.001). Mean +/- SEM for L/SF ratio was 0.817 +/- 0.013 and 0.598 +/- 0.019 in groups A and B, respectively (P <.001). For prediction of postnatal respiratory outcome, the area under the ROC curve for lung volume and L/SF ratio combined was 0.990, significantly higher than that for lung volume alone (P <.05). CONCLUSION: Simultaneous measurement of fetal lung volume and signal intensity on MR images is a promising method for predicting fetal pulmonary hypoplasia.

Fetal Organ Maturity↗

PubMedDate not supplied

A charcoal sampling method and a colorimetric analytical procedure for carbon disulfide. Measurement data from a viscose rayon manufacturing plant.

A charcoal sampling method and a colorimetric analytical method for carbon disulfide were developed. The methods were validated at relevant concentration of CS2. Precision and accuracy were acceptable (23%-6% and 36%-1%) at 25-400 micrograms CS2 deposited on the solid sorbent. The methods were calibrated with charcoal tube sampling and GC-FPD analysis. Regression analysis was performed on duplicate samples and a correlation coefficient of 0.96 and a regression coefficient of 0.8 were obtained. Occupational hygiene measurements were performed in a rayon manufacturing plant. A great proportion of TWA concentrations exceeded the swedish TLV (16 mg/m3) at all sample sites.

Air Pollutants, Occupational↗

PubMedDate not supplied

Computational simulation of biomechanics in e-PTFE and venous Miller's cuffs: implications for intimal hyperplasia.

A computational distal end-to-side Miller's cuff anastomotic model was used to analyse the possible difference in intimal hyperplasia (IH) formed between e-PTFE and venous cuffs. A large strain FEA model was used to compute the strain after physiological loading and the deformed geometries used as wall boundaries for CFD analysis. Regression analysis was performed to investigate relationships between mechanical factors and prior IH. The results showed that the venous Miller's cuff anastomosis deformed twice as much as the e-PTFE cuff and that the expansion of both cuffs generated elevated strains in the artery floor while the fluid shear indices were qualitatively similar in each case. In the e-PTFE cuff, the strain and OSI correlated with IH in a proportional and equivalent manner; however, these regressions grossly over-estimated the predicted IH in the vein cuff. Thus, biomechanical effects may be important in synthetically cuffed anastomoses, but do not account for the reduced IH in venous cuffed anastomoses.

Anastomosis, Surgical↗

PubMed1981

Long-term stability of a stabilized liquid quality-control serum.

To evaluate the long-term stability of a new liquid quality-control serum ("Decision", Beckman Instruments, Inc.) stabilized with ethylene glycol (330 mL/L), we analyzed it for 22 commonly measured analytes during storage at 2--8 degrees C for 24 days or -15 to -20 degrees C for 55 weeks. Three separate laboratories replicated the analyses, using various analytical methodologies. The data were subjected to linear regression analysis, regressing concentration on time. Analytes were considered unstable when the linear regression coefficient was unequal to zero with 95% or greater probability in all three laboratories. By this criterion all of the analytes were stable for at least 24 days when the control serum was stored at refrigerator temperature and for at least 55 weeks at freezer temperature. We conclude this material is a satisfactory substitute for existing lyophilized quality-control materials and offers certain advantages: stability, vial-to-vial uniformity, decreased waste, and eliminated reconstitution.

Blood Chemical Analysis↗

PubMed1994

The effect of age on plasma level of setiptiline maleate in depressed patients.

1. Setiptiline maleate (SPT) was administered orally to 45 subjects aged 22-86 years and steady state plasma levels were determined by mass fragment chromatography (GC-MF) to examine the effect of aging on those values. 2. There was a significant correlation between the plasma levels and daily dose. However, there was a wide interindividual variability. 3. Dose-corrected plasma level (DC-PL), or values corrected by dividing the plasma level by daily dose/body weight, was used as the systemic drug clearance parameter. 4. DC-PL was compared among 7 age groups of the subjects distributed in 10-year-intervals. DC-PL showed no difference among groups of subjects between the > 29 years bracket to the 70 years bracket, but showed significantly higher values in those in the > 80 bracket compared to all age groups and subjects in the < 79 bracket. 5. There was a significant correlation between the age of patients and DC-PL according to polynomial response curve analysis. Regression analysis yielded the equation y = -52.72 + 7.05 x -0.17 x2 + 0.01 x3 (n = 45, r = 0.49, p < 0.01).

Adult↗