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PubMed1990

GM1 gangliosides in the treatment of spinal cord injury: report of preliminary data analysis.

A prospective, randomized, placebo-controlled, double-blinded spinal cord injury GM1 ganglioside drug trial was completed. Of the 37 patients entered over a 16 month period, 34 patients (23 cervical and 11 thoracic injuries) received the test drug protocol and completed the one year follow up period. The neurologic recovery was quantified by serial measurement of the ASIA motor score throughout the acute hospital course and one year long follow up period. The primary variable used to assess neurologic recovery was the difference in the ASIA motor score from the admission value to the value at one year. The GM1 group had an average motor recovery of 36.9 points whereas the placebo group had an average change of 21.6 points (t-test difference, p = 0.088). Analysis of the secondary variable, the area under the ASIA motor score versus the logarithm of time, and the use of rank order nonparametric statistic on both the primary and secondary variables to sort neurologic recovery obtained similar statistical differences between the GM1 and placebo treatment groups. Randomization imbalances in baseline severity of injury and division of cervical and thoracic injury occurred in the trial. Because of this fact and the small sample size of the study verification of these results by a larger study is required.

Double-Blind Method↗
PubMed1990

Assessment of quality of life in school-aged children: a method--phase I.

This is part one of a programme of research directed toward the assessment of the Quality of Life (QOL) in chronically ill school-aged children. Phase I empirically derived QOL indicators of specific value to school-aged children. The ultimate purpose is to help health care professionals reduce or eliminate adverse consequences of chronic illnesses and their treatment in school-aged children through systematic identification and evaluation of these consequences as perceived by children. A convenience sample of 96 well children, aged 7 through 12 years, were interviewed to identify QOL indicators. Data collected included: demographic profiles of the child and parents; three wishes projective question (obtains data about the child's fantasies and wishes); semi-structured interviews (obtains information regarding the physical, psychosocial, and social development while focusing on the child's activities, family life, and home environment); and What Worries You (Your Child) the Most Questionnaire (lists 30 anxiety-provoking childhood experiences). Descriptive and nonparametric statistics will be used to describe the sample and compare the child and parent's responses, respectively. Data from the interviews will be analyzed to identify common themes. A category system was inductively derived to from the themes. The specific QOL indicators will be derived from the categories to provide a foundation for an instrument to psychometrically tested. This instrument will then be modified for use with children with chronic illness.

Child↗
PubMed1989

Prognostic significance (relapse, non-relapse) of nuclear shape parameters in lymph node negative breast cancer.

A series of 15 postmenopausal patients with stage I invasive breast cancer (pT1-2, pNO, cMO) of uniform histologic type (ductal, NOS) was selected from the Basel Cancer Registry for retrospective analysis. A group of seven patients with a minimal disease-free survival of 9 years was compared to a group of eight patients with clinical and/or histopathological relapse within 8 years of mastectomy. Computer-assisted morphometry of cancer nuclei in routine histological material was used to investigate possible correlations of clinical outcome with nuclear size and shape parameters. Significant differences were found for certain shape descriptors by nonparametric statistical analysis. Stepwise discriminant analysis was applied to find the best combination of parameters separating the two prognostic groups. Application of the 'leaving one out method' showed correct classification in 6 of 8 recurrent cases and in all non-recurrent cases. The number of patients is small, therefore the results should be carefully interpreted.

Breast Neoplasms↗
PubMed1989

An evaluation of chiropractic manipulation as a treatment of hyperactivity in children.

The principle aim of this study was to determine the effectiveness of chiropractic manipulative therapy in the treatment of children with hyperactivity. Using blinds between investigators and a single subject research design, the investigators evaluated the effectiveness of the treatment for reducing activity levels of hyperactive children. Data collection included independent evaluations of behavior using a unique wrist-watch type device to mechanically measure activity while the children completed tasks simulating school-work. Further evaluations included electrodermal tests to measure autonomic nervous system activity. Chiropractic clinical evaluations to measure improvement in spinal biomechanics were also completed. Placebo care was given prior to chiropractic intervention. Data were analyzed visually and using nonparametric statistical methods. Five of seven children showed improvement in mean behavioral scores from placebo care to treatment. Four of seven showed improvement in arousal levels, and the improvement in the group as a whole was highly significant (p = 0.009). Agreement between tests was also high in this study. For all seven children, three of the four principal tests used to detect improvement were in agreement either positively or negatively (parent ratings of activity, motion recorder scores, electrodermal measures, and X-rays of spinal distortions). While the behavioral improvement taken alone can only be considered suggestive, the strong interest agreement can be taken as more impressive evidence that the majority of the children in this study did, in fact, improve under specific chiropractic care. The results of this study, then, are not conclusive, however, they do suggest that chiropractic manipulation has the potential to become an important nondrug intervention for children with hyperactivity. Further investigation in this area is certainly warranted.

Attention Deficit Disorder with Hyperactivity↗
PubMedDate not supplied

Double-blind, placebo-controlled clinical evaluation of guaimesal in outpatients.

One hundred and forty outpatients, males and females aged 14 to 70 years, with acute febrile bronchitis, afebrile chronic bronchitis, or flares of chronic bronchitis were treated for seven days with one soft gelatin capsule (500 mg) of guaimesal thrice daily or matching placebo. No other potentially interfering treatment (antibiotic, antipyretic, or anti-inflammatory) was administered concomitantly. Before and after treatment, vital capacity, residual volume, and maximum expiratory volume per second were measured and recorded. Both before treatment and after 2, 4, and 7 days of treatment, body temperature was measured and cough frequency and intensity as well as expectorate amount and fluidity were scored and recorded along with the total symptom score. At the end of treatment, the overall clinical efficacy was rated and recorded. Potential side effects were monitored by questioning the patients; general safety (laboratory tests) was not monitored. All data were analyzed according to multivariate, parametric, and nonparametric statistical methods and stratified by treatment, sex, age, and diagnosis. For each monitored symptom and sign, guaimesal exhibited a favorable effect which was significantly greater in extent and significantly faster in recovery rate than that associated with spontaneous recovery. Within two days from the start of therapy, fever, cough frequency and intensity, and expectorate fluidity had significantly improved. By the fourth day the expectorate amount had significantly decreased. Further improvement was noted at subsequent times of observation. After a week, according to the spirometric parameters, the respiratory function was restored to a considerable extent. Overall, 75.7% of the patients receiving guaimesal experienced complete or almost complete recovery within the period of observation. With placebo, occasional improvement was seen for cough intensity and for expectorate amount, and this improvement was significantly less in extent and significantly slower than that recorded with guaimesal. Overall, 8.6% of placebo-treated patients experienced a clinically detectable degree of recovery. The subjective tolerance of guaimesal was comparable to that of placebo in terms of both the frequency and the nature of the side effects. Mild, transient gastric effects were reported by 11.4% of patients receiving guaimesal and by 8.6% of patients receiving placebo. These effects did not require a variation of dose or specific treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1988

Coronary bypass grafting after failed elective and failed emergent percutaneous angioplasty. Relative risks of emergent surgical intervention.

Emergency coronary artery bypass grafting after failed elective percutaneous transluminal coronary angioplasty can be performed with acceptable complication rates. Recently, however, a new class of patients with unsuccessful angioplasty has evolved with the use of thrombolytic therapy and emergent angioplasty as treatment for developing acute myocardial infarction. The efficacy of surgical intervention after failure of angioplasty in this setting has not been demonstrated. This report compares the results of coronary bypass done emergently after either failed elective or failed emergent angioplasty. Between March 1984 and September 1986; 1350 angioplasty procedures were performed at our institution, 393 for acute myocardial infarction. Of the 111 patients who came to operation, 42 had had unsuccessful elective angioplasty and 69 unsuccessful angioplasty done in the clinical setting of an evolving acute myocardial infarction detected by electrocardiographic criteria. Twenty-one of the 42 patients having unsuccessful elective angioplasty (group I) and 32 of the 69 with unsuccessful emergent angioplasty (group II) underwent emergency coronary artery bypass grafting. A retrospective nonparametric statistical comparison of the two groups was performed. Age, preoperative ejection fraction, distribution of vessels undergoing angioplasty, and number of vessels bypassed were not statistically different. All group II patients received thrombolytic therapy, and a reperfusion catheter was used in over half the patients in each group. Three group I and six group II patients required a preoperative balloon pump, and half the patients in each group required postoperative inotropic support. One patient in group I (4.7%) and two patients in group II (6.2%) died (no significant difference). Only five patients in group I (23.8%) and 11 in group II (34.3%) had enzymatic and electrocardiographic evidence of an acute myocardial infarction at discharge. Six patients in group II (15.6%) required reexploration for bleeding, versus none in group I (p = 0.04). Nonhemorrhagic complication rates, mean in-patient and acute care days, total hospital charges, and blood product utilization rates were not statistically different. These data indicate that emergency coronary artery bypass grafting can be performed when necessary in the setting of failed emergent percutaneous transluminal coronary angioplasty with results comparable to coronary bypass after failed elective angioplasty.

Angioplasty, Balloon↗
PubMed1988

Measures of central tendency, variability, and relative standing in nonnormal distributions: alternatives to the mean and standard score.

There are two major disadvantages to reporting test results in standardized scores such as z-scores or t-scores when describing individuals with disabilities. (1) Raw scores on many tasks from disabled individuals are notoriously nonnormal. They are asymmetric, in that they are skewed toward poor scores. (2) Low z-scores give a false impression of dysfunction because able-bodied subjects are often grossly overqualified for the application in question; they may have levels of strength or quickness several orders of magnitude greater than what is needed to do the assessment task. A recommended alternative is to describe the performance of disabled individuals using nonparametric statistics, and to report scores in boxplots, showing the extremes, the median, and the quartiles. Such points are easy to calculate and to interpret, and they are robust against outliers.

Disability Evaluation↗
PubMed1986

Mespirenone and other 15,16-methylene-17-spirolactones, a new type of steroidal aldosterone antagonists.

The ability of a series of 15,16-methylene-spirolactones in comparison to known antimineralocorticoids to inhibit the renal actions of aldosterone was tested in adrenalectomized, glucocorticoid-treated rats. The standard procedure involved continuous i.v. infusion with an isotonic solution of low sodium content (0.05% NaCl + 5.2% glucose, 3 ml/rat/h) supplemented with d-aldosterone [1 micrograms/(kg X h)] resulting in a long-lasting reduction of renal sodium excretion, increase of renal potassium excretion and hence decrease of the urinary Na/K-ratio. In some experiments sodium input was increased (0.2% NaCl + 4.3% glucose or 0.9% NaCl, respectively). The test drugs either were administered orally 1 h before start of the infusion or were added to the infused solution. With the exception of two steroids which could only be tested at single doses, all compounds were administered at three doses ranging from 2.2 to 40 mg/kg (p.o.) or from 0.83 to 6.7 mg/kg/h (i.v.). Spironolactone or spirorenone (oral administration) and potassium canrenoate (i.v. infusion) served as reference compounds. The antimineralocorticoid activity of the steroids was judged by the increase in the aldosterone-lowered Na/K-ratio in urine which was collected at hourly intervals for 15 or 21 h, respectively. Adrenalectomized, glucocorticoid-treated rats receiving an i.v. infusion without aldosterone were used as controls. To obtain preliminary information on potential antiandrogenic and progestogenic (side-)effects, binding of the test-compounds to androgen receptors (rat prostate cytosol) and progestogen receptors (rabbit uterus cytosol) was measured in vitro using 3H-dihydrotestosterone (DHT) and 3H-progesterone (prog.) as tracer and unlabelled DHT and prog. as references. All steroids tested exhibited antimineralocorticoid activity. For compounds tested at three doses levels the potency relative to the standard used was evaluated using regression analysis based on the Na/K-ratio or the log (Na X 100)/K-ratio. The relative potency of the other compounds was estimated by comparing the biological effect of single doses of test drug and standard drug, respectively, using nonparametric statistical tests.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1988

Thirty-five years of Tropical biology: a quantitative history.

Citation indices are inappropriate measures of scientific output and impact. For that reason, nonparametric statistics were preferred to analyze 35 years of publication on Tropical biology in the Revista de Biología Tropical. The most frequent subjects are animal taxonomy, human biology-including medicine- ecology and animal behavior. Botany papers are less frequent and mainly deal with morphology and taxonomy. Applied studies are not predominant. In that period, only one case of unethical experimentation with humans was discovered in a paper of Mexican origin. The proportion of foreign institutions publishing in the journal has increased from 23% (1953-1963) to 50% in the last decade; similarly, the number of studies done in the Neotropics is on the rise. English and Spanish are equally frequent, although English is the basic language of ethology and evolution and Spanish predominates in papers on animal morphology and parasitology. Most Costa Rican authors publish in Spanish, in contrast with many of their Latin American colleagues. In recent years, there is a tendency to publish shorter papers written by more than one author. The Revista de Biología Tropical, covered by 18 data bases, accounts for most exchanges and sales in the Universidad de Costa Rica and has worldwide distribution.

Biology↗
PubMed1987

The spatial distribution of neurons and glia in human cortex based on the poisson distribution.

A method was devised that employs deviations from the Poisson distribution to analyze the spatial arrangement of neurons and glia in human cerebral cortex. A field of randomly distributed points equal in number of a sample field of neuronal or glial cells is generated by computer, and the proportion of cells in the sample field that are closer to the nearest neighboring cells than to the nearest randomly distributed point is determined. We call this proportion the "Poisson ratio." When the cells are randomly distributed, the Poisson ratio is equal to 0.5. If the Poisson ratio is less than 0.5, the cells are farther away from one another than a random distribution would predict (exclusionary pattern); if the Poisson ratio is greater than 0.5, the cells are closer to one another than a random distribution would predict (clustering). A simple nonparametric statistical test is used to determine the significance of differences in the ratios. This method was applied to samples of human cerebral cortex in order to test the hypothesis that patients with schizophrenic psychosis may have an altered pattern of neuronal clustering. The analysis revealed that there is no difference in the nearest-neighbor distribution of either neurons or glia between psychotic patients and controls. It was found, however, that there is a highly significant difference in the spatial distribution of neurons versus glia in human cerebral cortex. Neurons of layers II to VI in the human cortex show greater-than-expected distances among them and are distributed according to an exclusionary pattern, while neurons in layer I show a clustering pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral Cortex↗
PubMed1987

Vital microscopic studies on the capillary distribution of leukocytes in the rat cremaster muscle.

Leukocyte capillary distribution was studied with vital fluorescence microscopy in the rat cremaster muscle. Ten terminal arterioles, each in a different animal, with 2 to 7 capillaries and with a total leukocyte flux ranging from 97 to 571 cells, were analysed. Nonparametric statistics was used for the analyses of the experimental data. In order to characterize the pathways for leukocyte flux in the networks, the leukocyte concentration for each capillary was calculated in relation to the network inflow leukocyte concentration and to the bifurcation inflow leukocyte concentration. The study shows a strong positive correlation between the relative capillary leukocyte concentration and the capillary volume flow and the position of the capillary in the network, respectively. There was no correlation between the relative capillary leukocyte concentration and capillary branching angle. A relative leukocyte concentration above unity, indicating an enrichment of leukocytes, was found in capillaries with a high volume flow and in capillaries located at the downstream end of the arterioles. In addition, the analyses show a very strong correlation between capillary volume flow and the position of the capillary along the arteriole, the capillaries located at the downstream end having the highest volume flows. In conclusion, the present study provides evidence for the existence of volume flow dependent preferential pathways for leukocyte passage across the capillary network in the rat cremaster muscle.

Animals↗
PubMed1979

Analysis of biochemical genetic data on Jewish populations: II. Results and interpretations of heterogeneity indices and distance measures with respect to standards.

A nonparametric statistical methodology is used for the analysis of biochemical frequency data observed on a series of nine Jewish and six non-Jewish populations. Two categories of statistics are used: heterogeneity indices and various distance measures with respect to a standard. The latter are more discriminating in exploiting historical, geographical and culturally relevant information. A number of partial orderings and distance relationships among the populations are determined. Our concern in this study is to analyze similarities and differences among the Jewish populations, in terms of the gene frequency distributions for a number of genetic markers. Typical questions discussed are as follows: These Jewish populations differ in certain morphological and anthropometric traits. Are there corresponding differences in biochemical genetic constitution? How can we assess the extent of heterogeneity between and within groupings? Which class of markers (blood typings or protein loci) discriminates better among the separate populations? The results are quite surprising. For example, we found the Ashkenazi, Sephardi and Iraqi Jewish populations to be consistently close in genetic constitution and distant from all the other populations, namely the Yemenite and Cochin Jews, the Arabs, and the non-Jewish German and Russian populations. We found the Polish Jewish community the most heterogeneous among all Jewish populations. The blood loci discriminate better than the protein loci. A number of possible interpretations and hypotheses for these and other results are offered. The method devised for this analysis should prove useful in studying similarities and differences for other groups of populations for which substantial biochemical polymorphic data are available.

Blood Group Antigens↗
PubMed1979

National Cooperative Crohn's Disease Study: study design and conduct of the study.

The design and execution of the National Cooperative Crohn's Disease Study are described in this paper. The Study incorporated several noteworthy features developed to meet specific demands of the disease and its therapy. A standard clinical grading system, the Crohn's Disease Activity Index (CDAI) was developed to allow uniform decentralized clinical evaluation and decision-making throughout the 5 yr of the study. All three drugs in widespread clinical use in Crohn's disease were studied both for suppressive and prophylactic efficacy and for toxicity. The study employed a scheme for double-blind evaluation of patient progress which allowed adjustment of prednisone dose according to the degree of illness and ensured continuous monitoring for serious toxicity of any study drug. Results were analyzed primarily by ranking the clinical outcome of every patient according to a uniform and detailed scheme and applying Wilcoxon nonparametric statistics. Outcome was also analyzed by life-table methods. Eleven hundred nineteen patients were entered and 604 patients were randomized at 14 study centers during the 5-yr duration of the study. Twenty patients were eliminated from analysis as not meeting diagnostic criteria for Crohn's disease, and another 15 patients were eliminated as not meeting other preestablished criteria for analysis. Nine percent of randomized patients, equally distributed in the four treatment groups, withdrew as noncompliant. Ninety percent of patients completed all or all but one protocol-specified visits, and 95% completed the final radiologic and sigmoidoscopic evaluation.

Azathioprine↗
PubMed1985

Outcome of patients treated by an aminoglycoside pharmacokinetic dosing service.

Differences in outcome between patients whose aminoglycoside dosing regimens were individualized by a clinical pharmacokinetic dosing service (CPDS) and patients who did not receive CPDS consultation were evaluated by retrospective chart review. Data for a number of dependent variables that might affect patient outcome were collected from the medical records of 42 patients with culture-proven gram-negative pneumonia or sepsis who had received CPDS dosing consultations and 60 similar patients who had not received CPDS consultations. Data were also collected for a number of analytical and categorical independent variables to evaluate sources of variation between the groups. Variables were compared using both parametric and nonparametric statistical tests. For patients whose dosing regimens had been individualized by the CPDS, length of aminoglycoside therapy and length of stay were significantly shorter, changes in serum creatinine concentration from baseline were significantly smaller, and mortality was significantly lower; morbidity was reduced by significantly fewer incidences of aminoglycoside nephrotoxicity. Significant differences existed between the mean dosing intervals, mean numbers of serum aminoglycoside concentration determinations, and mean baseline serum creatinine concentrations for the two groups. Although a favorable difference in patient outcome was demonstrated for patients whose dosing regimens were individualized by the CPDS, unmeasurable differences between the two groups of patients make it difficult to attribute the difference solely to the effect of the dosing service.

Adolescent↗
PubMed1979

Correlation of in vitro growth properties and tumorigenicity of Syrian hamster cell lines.

Several in vitro phenotypic characteristics frequently associated with neoplastic cells were examined in a series of spontaneous and benzo(a)pyrene-induced Syrian hamster clonal cell lines which differed in their degree of tumorigenicity. Nonparametric statistical analysis demonstrated cloning efficiency in semisolid agar, enhanced fibrinolytic activity, decreased serum requirement for growth, decreased organization of intracellular actin, and increased cloning efficiency in liquid medium to be correlated with tumorigenicity. These correlations were not only qualitative but also quantitative. This suggests that the factors determining the degree of tumorigenicity of a cell can be cellular growth properties.

Actins↗
PubMed1982

A comparative study of metronidazole and sulfasalazine for active Crohn's disease: the cooperative Crohn's disease study in Sweden. I. Design and methodologic considerations.

The design and execution of the Cooperative Crohn's Disease Study in Sweden are described in this paper. A double-blind, double-dummy, crossover (2 X 4 mo) technique was used to compare the suppressive efficacy of metronidazole (0.4 g b.i.d.) and sulfasalazine (1.5 g b.i.d.). The number of randomized patients (78) presented approximately one-third of the available population. The Crohn's Disease Activity Index and the plasma level of orosomucoid were the main variables for clinical evaluation. Results were analyzed primarily in the first treatment period by ranking the clinical outcome of every patient according to a uniform and detailed scheme and applying Wilcoxon nonparametric statistics. The cross-over data only served as additional information. Thirty-six patients had had earlier and mostly positive experience with sulfasalazine. Repeated plasma drug analysis indicated good compliance. The blindness of the trial was tested and appeared satisfactory. The coordination of the trial proceeded as planned. A lack of full conformity in the electroimmunoassay of orosomucoid was taken care of satisfactorily.

Adult↗
PubMedDate not supplied

Prognostic value of cytologic examination of peritoneal washings in patients with endometrial carcinoma.

Peritoneal pelvic washings from 54 women with pathologic stage I endometrial carcinoma were evaluated in a blind retrospective fashion for the concentration of malignant cells present. None of the 42 patients with normal washings developed recurrence after a median disease-free survival of 36 months. Of the 12 patients with adenocarcinoma in the washings, 4 had high concentrations of malignant cells (greater than 1000 cells/100 ml sample), and all 4 died as a consequence of carcinoma within two years. The remaining eight patients had lower concentrations of malignant cells in the washings (less than 1000 cells/100 ml sample), and six of these patients had no evidence of disease after 37 to 64 months. Cox's nonparametric statistical model showed that increasing concentrations of adenocarcinoma cells in washings significantly shortened the time to recurrence of disease. The abundance of malignant cells has prognostic importance in identifying those patients with pathologic stage I disease who may require more aggressive therapy.

Adenocarcinoma↗