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PubMed2000

Effect of a la carte and snack bar foods at school on children's lunchtime intake of fruits and vegetables.

OBJECTIVES: To compare lunch fruit, juice, and vegetable (FJV) intake of fourth-grade students who receive only National School Lunch Program meals and fifth-grade students who also have access to a school snack bar and to compare FJV intake by meal source among fifth-grade students. DESIGN: Cross-sectional study: students completed FJV preference questionnaires and 5 days of lunch food records in classrooms. SUBJECTS/SETTING: 312 fourth- and 282 fifth-grade students in south Texas. MAIN OUTCOME MEASURES: Mean FJV consumption. STATISTICAL ANALYSES PERFORMED: Descriptive statistics, correlation analyses, analysis of variance, analysis of covariance. RESULTS: Fourth-grade students (n = 312) consumed significantly more fruits, juices, and vegetables (0.80 serving) than fifth-grade students (n = 282) (0.60 serving). Students whose parents reported a high school education or less consumed more regular and total vegetables than students whose parents reported some college or higher education. There were no interaction effects among gender, grade, ethnic, or family education groups. Fifth-grade students who ate only snack bar meals consumed significantly less total fruits, juices, and vegetables (0.40 serving) than fifth-grade students who ate school lunch meals (0.82 serving). Controlling for FJV preferences did not change the main effect for grade level in the FJV consumption models. APPLICATIONS/CONCLUSIONS: FJV consumption during school lunch is low. School foodservice staff should identify FJV items that middle school students prefer and increase availability of those items in middle school cafeterias and snack bars.

Beverages↗
PubMed1999

Temporary neurological dysfunction after deep hypothermic circulatory arrest: a clinical marker of long-term functional deficit.

BACKGROUND: With increasing clinical experience, it has become clear that two distinct forms of neurological injury occur after operations on the thoracic aorta that require temporary exclusion of the cerebral circulation. Traditionally, evaluation of neurological outcome was limited to reporting the incidence of postoperative stroke related to ischemic infarcts due to particulate embolization. More recently, the symptom complex defined as "temporary neurological dysfunction" (TND) was recognized as a functional manifestation of subtle and presumably transient brain injury, but whether this early postoperative syndrome is associated with long-term deficits of cognitive and intellectual functions has not been established. METHODS: With Institution Review Board approval, 105 patients undergoing elective thoracic aortic surgery were entered into a protocol involving neuropsychological evaluation with a battery of tests preoperatively, and 1 and 6 weeks postoperatively. Patients who could not be tested adequately or had documented strokes were eliminated from final analysis. Seventy-one patients completed the neuropsychological evaluation, which consisted of eight tests consolidated into five domains: attention, cognitive speed, memory, executive function, and fine motor function. Independent observers also determined whether temporary dysfunction was present, and graded its severity based on a fixed but subjective clinical scale, ranging from simple disorientation and lethargy or confusion (grade 1-2) to prolonged extreme agitation or psychotic behavior requiring treatment with psychotropic drugs (grade 3-5). Data were normalized to baseline values, and were analyzed using analysis of variance, analysis of covariance (ANCOVA), and chi2 as necessary. RESULTS: A previous analysis had shown that patients who could not be tested or had poor scores 1 week postoperatively were more likely to perform poorly at 6 weeks (odds ratio 5.27, p < 0.01). In the current study, in order to determine the clinical relevance of TND, patients were analyzed retrospectively according to their performance in neuropsychological testing: patients with no change or a decline of less than 50% in tests of memory, motor function, and attention 1 week postoperatively (group 1, n = 49) were compared with those with a negative change exceeding 50% in the same functions at 1 week (group 2, n = 22). The overall incidence of TND was 28.1% (20/71). The incidence of TND in group 2 (14/22, 63%) was significantly higher than in group 1 (6/49, 12%; p = 0.0006). Similarly, the severity of TND (as assessed by clinical score > 2) was also significantly higher in group 2 (11/14) compared with group 1 (0/6; p = 0.006.) CONCLUSIONS: The incidence and severity of clinically apparent temporary neurological dysfunction correlates significantly with poor performance on neuropsychological tests 1 week postoperatively. Such poor performance predicts continued deficits in memory and motor function at 6 weeks. Thus, TND may not be a benign self-limited condition as previously supposed, but rather a clinical marker for insidious but significant neurological injury associated with measurable long-term deficits in cerebral function. A concerted effort to reduce the incidence of this complication is therefore necessary.

Aged↗
PubMed1998

The effect of high-dose albumin therapy on local cerebral perfusion after transient focal cerebral ischemia in rats.

We have shown that high-concentration albumin therapy is markedly neuroprotective in focal cerebral ischemia. The present study was conducted to ascertain the degree to which hemodynamic alterations are responsible for this therapeutic effect. Normothermic, physiologically regulated male Sprague-Dawley rats received a 2-h period of middle cerebral artery occlusion (MCAo) by insertion of an intraluminal suture coated with poly-L-lysine. Albumin (25% human serum albumin solution) or vehicle (0.9% sodium chloride) was administered intravenously at a dose of 1% of body weight immediately after suture withdrawal following 2-h MCAo. Local cerebral blood flow (LCBF) was measured autoradiographically with 14C-iodoantipyrine after 1 h of recirculation. Novel image-processing methods were used to compare average LCBF data sets against previously obtained infarction-frequency data on a pixel-by-pixel basis. Albumin therapy reduced mean hematocrit by 42% but produced no other systemic alterations. Pixel-based histopathological analysis revealed large, consistent cortical and subcortical infarcts in saline-treated rats with MCAo; albumin therapy reduced mean cortical infarct volume by 85%. Within regions showing albumin-associated neuroprotection, numbers of pixels having LCBF in the upper ischemic-core flow range (0.12-0.24 ml g-1 min-1) were reduced by 8.6-fold by albumin therapy when compared to saline-treated rats; and numbers of pixels with LCBF in the lower penumbral flow range (0.24-0.36 ml g-1 min-1) were reduced by 3. 1-fold in albumin-treated rats (p=0.04 by repeated-measures analysis of variance). Analysis of the [albumin-saline] 3-dimensional difference-image data set revealed a circumferential zone of statistically significant albumin-associated LCBF increase within the posterior portion of the ischemic hemisphere, surrounding the core-region of prior ischemia. Thus, high-concentration albumin therapy improves local perfusion to regions of critical LCBF reduction. The spatial extent of this LCBF effect, however, appears too small to account fully for the marked neuroprotective efficacy of this therapy. We suggest that other, non-hemodynamic mechanisms may also be contributory.

Animals↗
PubMed2000

Hospitalization for peptic ulcer bleeding: evaluation of a risk scoring system in clinical practice.

BACKGROUND: Upper gastrointestinal tract haemorrhage is a common cause of hospitalization: resource utilization in management of peptic ulcer bleeding varies considerably with no apparent effect on patient outcome. Several risk score systems based on endoscopic and clinical data have been proposed and validated in order to aid patient management. AIM: To assess clinical reliability of a scoring system and to define guidelines to improve efficiency of patient management without reducing efficacy METHODS: We considered all patients admitted to our unit for bleeding peptic ulcer over a one-year period. Every patient had an early endoscopy (within 12 hours) and therapy according to the appearance of the ulcer defined by Forrest classification. All subjects were classified into low-, intermediate- and high-risk patients on basis of clinical and endoscopic features according to "Cedar Sinai Medical Center predictive index" which was applied retrospectively in first six months then perspectively for the last period using the results obtained from first semester. For each risk group, we compared Length of Hospital Stay number of blood units used in transfusion, rebleeding rate, need for surgery as well as mortality in the two periods, using Student t test. We correlated Length of Hospital Stay and every score parameter by applying analysis of variance to results over the one-year period. RESULTS: Study population consists of 91 patients. Recurrent bleeding was observed in only three entering the high-risk group, only one of whom needed surgery Overall mortality was 9.8% (9 patients, only one for rebleeding). Variance analysis showed that the only parameter of the "Cedar Sinai Medical Center predictive index" which correlated with Length of Hospital Stay was comorbidity (p < or =0.05). Comparing the two periods, a close application of the score in the last six months allowed Length of Hospital Stay to be reduced in low-risk patients (t test with p=0.004) resulting in early discharge of 33% of cases without affecting patient outcome. CONCLUSIONS: This study confirms the reliability of the "Cedar Sinai Medical Center predictive index" in clinical practice improving the strategy of applying economic resources. Longer Length of Hospital Stay of intermediate- and high-risk groups is influenced more by comorbidities than by endoscopic findings. Early discharge was possible in one third of low risk patients. An accurate evaluation clinical para meters on admission together with early endoscopy may achieve the goal of reducing costs with a correct patient management.

Adult↗
PubMed2003

A comparison of antimicrobial susceptibility patterns for Staphylococcus aureus in organic and conventional dairy herds.

Selective pressure from antimicrobial use, mutations, or acquisition of foreign resistance determinants mediate antimicrobial resistance. If antimicrobial use is the major selective pressure encouraging the development of resistance, then reduced use should result in decreased resistance. We compared antimicrobial susceptibility patterns of Staphylococcus aureus isolates obtained from milk samples from 22 organic (nonantibiotic using) dairy herds to isolates from 16 conventional dairy herds. Susceptibility testing was performed by disk diffusion, and zone diameters were recorded in millimeters for 144 isolates from organic farms and 117 isolates from conventional farms and were also classified as susceptible or not-susceptible (intermediate and resistant categories combined). Strength of association between high or low use and proportion susceptible was evaluated by Chi-square analysis and differences in mean zone diameter for isolates from organic farms versus isolates from conventional farms were compared by analysis of variance. Analysis was done for each antimicrobial and deemed significant at p < or = 0.05. Differences in antimicrobial susceptibility were observed between S. aureus isolates from organic and conventional herds for seven of the nine antibiotics studied. Herds that were certified organic had S. aureus isolates that were more susceptible to antimicrobials. Overall, S. aureus isolates from both organic and conventional herds showed good susceptibility to most commonly used bovine mastitis antimicrobials; however, isolates from organic herds were significantly more susceptible. Longitudinal studies of herds undergoing the transition to organic farming would help elucidate the dynamics of antimicrobial resistance and the potential return of antimicrobial susceptibility.

Animal Husbandry↗
PubMed1994

HIV type 2 proviral load measured by quantitative polymerase chain reaction correlates with CD4+ lymphopenia in HIV type 2-infected individuals.

The efficiency of detection of 2 sets of primer pairs from putatively conserved regions of the human immunodeficiency virus type 2 (HIV-2) genome were assessed in 86 seropositive individuals from The Gambia by nested polymerase chain reaction (PCR). HIV-2 long terminal repeat (LTR) target sequences were detected in DNA extracted from peripheral blood mononuclear cells (PBMCs) in 84 of 86 (97%) individuals whereas HIV-2 integrase (pol) gene sequences were detected in 39 of 41 (95%) individuals. The use of LTR target sequences and recombinant Pfu DNA polymerase, rather than Taq polymerase, in a modified secondary amplification reaction mediated the incorporation of 35S-labeled nucleotides in a quantitative radiometric assay. This sensitive assay was used to quantify HIV-2 proviral DNA in clinical samples and compared well with estimations by limiting end-point dilution of target molecules. A linear response between counts and the number of copies amplified from serial dilutions of pROD10 plasmid DNA (3-2000 copies) yielded a standard curve to allow extrapolation to clinical data. Increased levels of HIV-2 proviral DNA, expressed as copies per 10(5) CD4-positive lymphocytes, were associated with declining CD4 count in 63 adult patients (Spearman rank correlation, r = -0.71, n = 63, p < 0.001) and with the occurrence of HIV-related clinical disease. Kruskall-Wallis analysis of variance analysis showed the mean proviral copy number (log10) to be significantly different between groups (p < 0.001) where CD4 counts were grouped as < 200/mm3 (3.4 +/- 1.05 copies), 200-500/mm3 (2.84 +/- 0.93 copies), and > 500/mm3 (1.88 +/- 0.43 copies).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2004

Construct validity of self-reported historical physical activity.

The purpose of this study was to determine the construct-related validity of self-reported historical walking, running, and jogging (WRJ) activity on the basis of data from the Aerobics Center Longitudinal Study (Dallas, Texas). A total of 4,100 men and 963 women underwent at least one medical examination between 1976 and 1985 and completed a follow-up questionnaire in 1986. Levels of glucose, cholesterol, and triglycerides, resting systolic blood pressure, body mass index (weight (kg)/height (m)(2)), and cardiorespiratory fitness were measured at the time of the medical examination. The follow-up questionnaire assessed WRJ and other strenuous activities for each year from 1976 through 1985. Data analysis included Spearman and partial correlations, analysis of variance, analysis of covariance, and t tests. Results indicated significant correlations between recalled WRJ and treadmill times for each year throughout the 10-year period (r = 0.40-0.61). Participants were classified as historically either sufficiently physically active to receive a health benefit or insufficiently active for a health benefit. Engaging in sufficient levels of historical WRJ was associated with higher treadmill times and lower body mass indices for men and women and lower triglyceride levels for men. Self-reported historical WRJ can be assessed with reasonable validity in comparison with measured treadmill performance, with no decay in accuracy of reporting for up to 10 years in the past.

Adolescent↗
PubMed2002

Integrated care pathways for vascular surgery: an analysis of the first 18 months.

OBJECTIVES: A review of the use of previously described integrated care pathways (ICPs) established for three elective vascular surgical procedures. DESIGN: A retrospective analysis of information gathered prospectively over an initial 18 month period of use of vascular surgical ICPs. SUBJECT: Patients admitted to a single vascular unit for "open" repair of abdominal aortic aneurysm (AAA), carotid endarterectomy, or femoropopliteal bypass grafting. METHODS: An analysis of variance data, length of stay, and costings after the use of ICPs, compared with previous clinical practice. RESULTS: Variance data were gathered for each of the three procedures. Variances of medication prescribing and delays in discharge were common to all procedures. In particular: (i) gastrointestinal complications were more specific to AAA repair and (ii) wound drains were removed a day later than originally proposed after femoropopliteal bypass. Overall, improved efficiency due to use of ICPs reduced the length of stay for all procedures, which was reflected in a potential cost saving of some 25%. CONCLUSION: There are clear benefits to the use of ICPs, resulting in more structured, efficient, and cost effective patient care. Recommended changes to current practice based on variance analysis will require continued audit to sustain this "evidence based" approach.

Aortic Aneurysm, Abdominal↗
PubMed1983

Histamine skin test in cluster headache: effects of dihydroergotamine with timed release.

The histamine skin test, as modified by Giacovazzo, was carried out on 20 patients with cluster headache and on 20 control subjects, 10 of whom suffered from migraine and 10 who were healthy volunteers not presenting any form of headache. The test was carried out before and after 30 days treatment with timed-release dihydroergotamine methanesulphonate in a dose of 10 mg/day. Data recorded on a "headache time chart" before and after treatment were evaluated by statistical analysis. Block variance analysis was used to evaluate results of three parameters (latency time, hyperemia diameter, extinction time) emerging from the histamine skin test before and after treatment. A statistical comparison was also made of data obtained in basal conditions in the three groups of subjects, in order to confirm the usefulness of this simple test in the diagnosis of cluster headache.

Adult↗
PubMed2005

Sub-chronic inhalation of high concentrations of manganese sulfate induces lower airway pathology in rhesus monkeys.

BACKGROUND: Neurotoxicity and pulmonary dysfunction are well-recognized problems associated with prolonged human exposure to high concentrations of airborne manganese. Surprisingly, histological characterization of pulmonary responses induced by manganese remains incomplete. The primary objective of this study was to characterize histologic changes in the monkey respiratory tract following manganese inhalation. METHODS: Subchronic (6 hr/day, 5 days/week) inhalation exposure of young male rhesus monkeys to manganese sulfate was performed. One cohort of monkeys (n = 4-6 animals/exposure concentration) was exposed to air or manganese sulfate at 0.06, 0.3, or 1.5 mg Mn/m3 for 65 exposure days. Another eight monkeys were exposed to manganese sulfate at 1.5 mg Mn/m3 for 65 exposure days and held for 45 or 90 days before evaluation. A second cohort (n = 4 monkeys per time point) was exposed to manganese sulfate at 1.5 mg Mn/m3 and evaluated after 15 or 33 exposure days. Evaluations included measurement of lung manganese concentrations and evaluation of respiratory histologic changes. Tissue manganese concentrations were compared for the exposure and control groups by tests for homogeneity of variance, analysis of variance, followed by Dunnett's multiple comparison. Histopathological findings were evaluated using a Pearson's Chi-Square test. RESULTS: Animals exposed to manganese sulfate at > or = 0.3 mg Mn/m3 for 65 days had increased lung manganese concentrations. Exposure to manganese sulfate at 1.5 mg Mn/m3 for > or = 15 exposure days resulted in increased lung manganese concentrations, mild subacute bronchiolitis, alveolar duct inflammation, and proliferation of bronchus-associated lymphoid tissue. Bronchiolitis and alveolar duct inflammatory changes were absent 45 days post-exposure, suggesting that these lesions are reversible upon cessation of subchronic high-dose manganese exposure. CONCLUSION: High-dose subchronic manganese sulfate inhalation is associated with increased lung manganese concentrations and small airway inflammatory changes in the absence of observable clinical signs. Subchronic exposure to manganese sulfate at exposure concentrations (< or = 0.3 mg Mn/m3) similar to the current 8-hr occupational threshold limit value established for inhaled manganese was not associated with pulmonary pathology.

Acute Disease↗
PubMed2003

Bivariate variance-component analysis, with application to systolic blood pressure and total cholesterol levels in the Framingham Heart Study.

BACKGROUND: The correlations between systolic blood pressure (SBP) and total cholesterol levels (CHOL) might result from genetic or environmental factors that determine variation in the phenotypes and are shared by family members. Based on 330 nuclear families in the Framingham Heart Study, we used a multivariate normal model, implemented in the software FISHER, to estimate genetic and shared environmental components of variation and genetic and shared environmental correlation between the phenotypes. The natural logarithm of the phenotypes measured at the last visit in both Cohort 1 and 2 was used in the analyses. The antihypertensive treatment effect was corrected before adjustment of the systolic blood pressure for age, sex, and cohort. RESULTS: The univariate correlation coefficient was statistically significant for sibling pairs and parent-offspring pairs, but not significant for spouse pairs. In the bivariate analysis, the cross-trait correlation coefficients were not statistically significant for all relative pairs. The shared environmental correlation was statistically significant, but the genetic correlation was not significant. CONCLUSION: There is no significant evidence for a close genetic correlation between systolic blood pressure and total cholesterol levels. However, some shared environmental factors may determine the variation of both phenotypes.

Adult Children↗
PubMed2004

Post-traumatic stress and disability.

BACKGROUND: Post-traumatic stress is thought to account for significant disability. It is also known to be highly comorbid with other psychiatric conditions such as depression and alcohol dependence. AIMS: To determine the relationship between post-traumatic stress, depression, alcohol dependence and disability. METHOD: Seventy armed services personnel were assessed for DSM-IV diagnoses of post-traumatic stress disorder, major depressive disorder and alcohol dependence, and with continuous measures of symptoms of post-traumatic stress, depression and alcohol dependence following a traumatic event. These variables, as predictors of disability (using the Sheehan Disability Scale), were analysed using multivariate analysis of variance, analysis of covariance and multiple regression backward elimination models. RESULTS: No significant interaction was found for the diagnostic variables even after controlling for the continuous symptom measures. In the regression models, symptoms of depression were a significant predictor of total disability (R(2)=0.39). Symptoms of alcohol dependence and post-traumatic stress did not significantly predict disability. CONCLUSIONS: Since post-traumatic stress was not found to be associated with disability, its clinical importance may be questionable.

Adult↗
PubMed2006

Suprasternal Doppler estimation of cardiac output: standard versus sequential combined spinal epidural anesthesia for cesarean delivery.

BACKGROUND: Sequential (Seq) combined spinal epidural (CSE) may provide better cardiovascular stability than standard (Std) CSE for cesarean delivery. We compared the cardiovascular stability of both techniques using suprasternal Doppler. METHODS: Healthy women (n = 40) scheduled for elective cesarean delivery were randomized into two groups; Std or Seq CSE. Serial measures of cardiac output indices, including minute distance, stroke distance, stroke volume, peak velocity, and corrected flow time, were recorded before and after intravascular fluid administration and after CSE. Women received either hyperbaric bupivacaine 10 mg (Std) or 5 mg (Seq) with intrathecal fentanyl 15 microg. An epidural top-up with bupivacaine 0.5% w/v (5 mL at 20 min in the Std group and 10 mL at 15 min followed by 5 mL at 25 min in the Seq group) was given if predefined sensory targets were not met. Data were collected every 5 min after intrathecal injection. Hypotension was treated with ephedrine. Statistical analyses included repeated measures analysis of variance, analysis of covariance and Student's t-test. P < 0.05 denoted significance. RESULTS: Results showed no difference in cardiac output, minute distance, stroke distance, stroke volume, peak velocity, or corrected flow time between groups over the first 20 min after spinal injection. For whole measurement periods, mean lowest values for these same measures showed no group differences. CONCLUSION: We therefore found no benefit in terms of cardiovascular stability of Seq to Std CSE for elective cesarean delivery in the healthy pregnant population.

Anesthesia, Epidural↗
PubMed2006

Effects of post-electrophoretic analysis on variance in gel-based proteomics.

2D electrophoresis (2DE) is a prominent separation method for complex proteomes. Although recent advances have increased the utility of this method in quantitative proteomics studies, many sources of variance still exist. This review discusses the post-electrophoretic sources of variance in current 2DE analysis. The essential improvements in protein visualization and software algorithms that have made 2DE a leading quantitative proteomics method are briefly reviewed. A number of shortcomings in the post-electrophoretic analysis of 2DE data that require further attention are highlighted. Topics discussed include protein visualization and image acquisition, internal standards and normalization methods, background subtraction algorithms, normality of distribution, and the need for standardized tests for the evaluation of 2DE analysis software packages.

Electrophoresis, Gel, Two-Dimensional↗
PubMed2006

Assessment of a practice effect in serial sensory organization testing scores of healthy adults.

This study assessed whether a practice effect occurs across five serial administrations of the sensory organization test. Composite equilibrium scores and mean equilibrium scores from 30 healthy volunteers (M age=36.9, SD = 12.2 yr.) performing each of the six test conditions were examined using a two-way repeated-measures analysis of variance. Analysis yielded a significant interaction between testing condition and time, as well as significant main effects for both condition and time. Pairwise comparisons showed significant differences among test conditions and the first and second times of test administration. Analysis of simple effects between the two administrations identified significant increases in composite equilibrium scores and mean equilibrium scores on two sway-referenced support surface conditions, vision removed and sway-referenced visual surround. An immediate increase in equilibrium scores suggests clinicians and researchers allow one pracatice trial before recording test scores for baseline measurements.

Adult↗
PubMed1996

Effects of aquatic therapy on joint flexibility and functional ability in subjects with rheumatic disease.

Currently, there is a deficit of objective data showing the efficacy of aquatic exercise therapy in improving function in individuals with rheumatic disease. The purpose of this study was to quantify the effectiveness of aquatic therapy in changing joint motion, functional status, assistance, pain, and difficulty in 13 subjects with rheumatic disease. Active joint motion and Functional Status Index scores of assistance, pain, and difficulty were taken prior to and following 8 weeks of aquatic therapy. Multivariate analysis of variance, analysis of covariance procedure controlling for pain, and a Pearson correlation between active joint motion and Functional Status Index changes and between assistance, pain, and difficulty scores of the Functional Status Index were conducted. Results showed a significant difference between the pre and post means of active joint motion, Functional Status Index, pain, and difficulty (p < .05); a significant, negative relationship between pain and active joint motion of select joints; and positive correlations between assistance and pain, assistance and difficulty, and pain and difficulty. The decreased pain and difficulty experienced in performing daily tasks contributed significantly (94%) to the overall increased functional status and active joint motion for select joints. These findings support aquatic therapy as an effective means of increasing joint flexibility and functional ability while reducing pain and difficulty with daily tasks.

Activities of Daily Living↗