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PubMed1988

Ontogeny of gonadotropic and thyrotropic cells in fetal mouse anterior pituitary. Comparison between two species C57 BL6 and Balb/C.

The fetal period constitutes a determinant stage in the ontogenesis of the hypothalamo-hypophysial-gonadal system. This work mainly concerns gonadotropic and thyrotropic functions and compares their different aspects in two strains of fetal mice. Balb/c and C57 BL6 fetal mice were studied at 16, 17, 18 and 19 days of gestation. The appearance and distribution of immunoreactive gonadotropic and thyrotropic cells of the anterior pituitary were observed by immunocytology using an indirect method with anti-porcine luteinizing hormone beta serum, anti-bovine thyrotrope hormone serum after saturation with bovine luteinizing hormone and anti-rat luteinizing hormone serum. In the two strains and in both sexes, LH gonadotropes appeared at 17 days of gestation and preferentially localized in the ventral part of the anterior lobe; a similar distribution was noted at 18 days and there was an increase in the number and staining intensity of labeled cells. By 19 days of gestation the gonadotrophs seemed more numerous, more generally distributed throughout the gland and often abutted to sinusoidal capillaries. An account of immunoreactive cells with anti-porcine luteinizing hormone serum and statistical evaluation of the results performed by variance analysis showed significant differences between the two strains. LH gonadotropic cells were always more numerous at each day of gestation in Balb/c fetuses especially in female fetuses. The possibility of a different evolution and/or differentiation for this cell population is discussed. Comparison of gonadotropic function between rat fetuses, mouse fetuses and human fetuses lead us to conclude that mouse fetuses appeared as an experimental model more closely related to human fetuses.

Animals↗
PubMed1987

Computed tomography brain changes in parkinsonian dementia.

In order to evaluate the relationship between brain atrophy and the motor and cognitive function in Parkinson's disease, we have evaluated CT changes in 132 consecutive patients and compared them to measures of physical and mental decline, using intercorrelations and variance analysis. The result demonstrated age as a most important factor relating to brain atrophy. After correction for this determinant, it became clear that the motor and cognitive parameters were interdependent but they affected similar CT parameters. The effect of motor decline was the stronger of the two and it was the only one which correlated with cortical atrophy. The results support the notion of subcortical changes underlying the dementia of Parkinson's disease.

Aged↗
PubMed1988

Polygenic control of quantitative antibody responsiveness: restrictions of the multispecific effect related to the selection antigen.

Among the differences observed between the various high (H) and low (L) antibody responder lines of mice resulting from distinct bidirectional selective breedings, one of the most puzzling is the variation in the "multispecific effect," i.e., in the modification of antibody responses to antigens unrelated to those used during the selection. The best examples are the H and L lines of selection IV, selected on the basis of responses to somatic antigen of Salmonella which do not differ in their antibody responses to sheep erythrocytes (SE). However, a wide range of variability is observed in the responses of (HIV X LIV)F2 hybrids to this antigen, and it was therefore hypothesized that distinct groups of genes might regulate antibody responses to SE and the somatic antigen. Indeed, a new selection (IV-A) for anti-SE responsiveness started from these (HIV X LIV)F2 successfully produced a high and a low anti-SE responder line. The results of selection IV-A and the variance analysis of (HIV-A X LIV-A)F2 hybrids are reported. They are roughly similar to those in selection I, also carried out for anti-SE responsiveness. In vivo attempts to identify the major regulatory mechanism which contributes to the interline difference indicate that the efficiency of macrophage accessory function has been modified in selection IV-A, as was observed in selection I, whereas this function did not differ in HIV and LIV lines. Probably in relation to the involvement of macrophage function there is a notable increase of the multispecific effect in selection IV-A when compared with selection IV. The results of selection IV-A demonstrate that responsiveness to heterologous erythrocytes and to somatic antigen of Salmonella are under separate polygenic control operating through distinct regulatory mechanisms. The choice of the selection antigen and immunization procedure is of major importance for defining the gene interaction operating in each selective breeding experiment and the extent of its multispecific effect.

Animals↗
PubMed1985

Cardiovascular changes and hearing threshold shifts in men under complex exposures to noise, whole body vibrations, temperatures and competition-type psychic load.

This study deals with changes in the temporary hearing threshold (TTS2), heart rate (HR), R-wave amplitude (RWA), diastolic blood pressure (DBP), systolic blood pressure (SBP), pulse pressure (PP) and reaction time (RT) in subjects (n = 108) who, while working on a choice reaction apparatus, were exposed in an exposure chamber to combinations of noise and vibration at dry bulb temperatures of 20 degrees and 30 degrees C. The study was carried out as a type 2-3-3 factorial experiment, the number of the exposure combinations thus being 18. To find out the effects of competition-type psychic stress, some of the subjects were placed in a competitive group and some in a non-competitive group. The members of the competitive group were given financial encouragement and information on their progress during the test, whereas those in the non-competitive group worked at the rate they considered best without any monetary rewards or interim information. The noise classes were: no noise, a stable broadband (bandwidth 0.2-16.0 kHz) A-weighted noise of 90 dB not related to competition, and a stable broadband A-weighted noise of 90 dB related to competition about the fastest reaction time. The vibration classes were: no vibration, sinusoidal whole body vibration (Z-axis) at a frequency of 5 Hz, and stochastic broadband (bandwidth 2.8-11.2 Hz) whole body vibration (Z-axis). The acceleration (rms) of both vibrations was 2.12 m/s2. One experiment consisted of a control period of 30 min, three consecutive exposure periods of 16 min with an interval of 4 min, and a 15-min recovery period. The variance analysis model best explained the variation in TTS2 values at 4 kHz and second best the variation in TTS2 values at 6 kHz; it explained the variation in HR values third best, the variation in SBP values fourth best and the variation in PP values fifth best. On the other hand, the model explained least well the variation in DBP and RWA values. In general, the explanatory power of the model increased together with the number of exposures. The psychic stress caused by competition accelerated the growth of the TTS2 values, HR values and SBP values, when the subjects were simultaneously exposed to noise or to a combination of noise and vibration. An interesting finding for the continuation of the research project was that sinusoidal and stochastic vibration affected the cardiovascular changes, temporary hearing threshold and reaction times in different ways.

Adolescent↗
PubMed1979

Influence of ciclazindol on monoamine uptake and CNS function in normal subjects.

The potential antidepressant drug ciclazindol inhibited dopamine uptake into human platelets without affecting 5-hydroxytryptamine uptake as compared with a control. It inhibited the tyramine pressor response less than desipramine after single 50-mg oral doses in 6 healthy volunteers under double-blind conditions. Compared with tandamine in a double-blind placebo-controlled study in nine healthy subjects, ciclazindol 50 mg orally caused no significant anticholinergic effects but reduced appetite according to an analysis of variance. Nonparametric analysis did not confirm the anorectic effect. Previous studies had shown that ciclazindol increased glucose uptake into isolated human skeletal muscle independently of insulin. Overall, ciclazindol resembles the antiobesity drug mazindol in molecular structure and pharmacological effects in man. Interactions with sympathomimetic amines and adrenergic neurone-blocking drugs cannot be excluded on the basis of these studies.

Adult↗
PubMed1975

Differential antianginal responsiveness to acebutolol.

Six unselected males suffering from documented coronary insufficiency and grade II to III angina were submitted to graded multistage treadmill exercise test on 3 separate occasions, 3.5 hours after ingestion of either 0, 200 or 400 mg of acebutolol, a new cardioselective beta-blocker. Control measures included the random allocation to 6 balanced sequences of administration, the rigid standardisation of double-blind experimental conditions and measurements, and two types of variance analysis (latin-square and split-plot). Performance was evaluated by measuring time elapsed before occurrence of anginal pain and ECG changes, peak heart rate, peak double product (heart rate x systolic pressure), and peak oxygen consumption. The mean values for all 5 criteria showed improvement with the 200 mg dose of acebutolol, and even more so with 400 mg, but this overall effect resulted mainly from the excellent response of 3 of the patients. When patients were grouped into 2 categories of responders and non-responders, a significant Dose x Category interaction was found for all criteria. Furthermore, maximal response under acebutolol was negatively correlated with values under placebo (0 mg); this correlation reached significance for peak heart rate and peak double product. It is concluded that (a) in responders, the beneficial effect of acebutolol was significant on all 5 criteria (p less than 0.05), (b) patients definitely fell into 2 categories of responsiveness and (c) the sensitivity of responders was partly linked to their performance under placebo and partly to unidentified individual factors.

Acebutolol↗
PubMed1988

Generality of test-session observations to kindergarteners' classroom behavior.

Test observations are integral components in the comprehensive assessment of children's academic talents and personal adjustment. They are used to validate standardized test scores obtained during test sessions and to draw inferences about children's general pattern of learning and social adjustment. Unfortunately, little empirical justification exists for extending inferences beyond the confines of test sessions. This issue was examined with 155 kindergarten children using the Stanford Binet Observation Schedule (SBOS), a popular instrument for the summative integration of test-session observations. Children's ratings on the SBOS were used to estimate teacher-observed behavior on the Guide to the Child's Learning Style (GCLS). SBOS and GCLS scores were subjected to independent principal components analyses with varimax rotation and, thereafter, to a joint canonical variance analysis. Weighted factor composites from two SBOS dimensions constituted the predictor data set and three GCLS dimensions the criterion data set. Although multivariate statistical significance was achieved (lambda = .834, F(6,200) = 3.18, p less than .005), cannonical redundancy showed merely 9.4% of classroom behavior predictable from test-session. Results are examined in light of research on the situational specificity of behavior.

Achievement↗
PubMed1988

Polycystic ovarian disease: endocrinological parameters with specific reference to growth hormone and somatomedin-C.

Thirty-three women (22-38 years old) with polycystic ovarian disease (PCOD) were included in this study. The criteria for diagnosis were: an LH/FSH ratio greater than 2.0; polycystic ovaries, diagnosed by means of palpation and ultrasound; androgenism and menstrual cycle abnormalities. Using endocrine parameters, we attempted to define distinct forms of PCOD. The patients were placed in three groups according to serum levels of testosterone (T) and 17 alpha-hydroxyprogesterone (17 alpha OHP) and the estrone/androstendione (E1/delta 4A) ratio. Patients in group I (n = 18) had an elevated T level (greater than 1.0 ng/ml) and a 17 alpha OHP level under 4.0 ng/ml. This type of POCD was called the "androgen" type. Patients in group II (n = 7) had normal T- and 17 alpha OHP levels under 4.0 ng/ml and an elevated (E1/delta 4A) ratio. This type of PCOD was called the "estrogen" type. Group III (n = 8) comprised patients with 17 alpha OHP levels over 4.0 ng/ml. This type of PCOD was called the "adrenocortical" type. In two patients of this group, a modified ACTH test revealed late-onset congenital hyperplasia. The endocrine parameters of the patients with PCOD were compared with those of 17 adult without signs of PCOD. Statistical evaluation was done by variance analysis. Women with acromegaly often show signs of androgenism as well as menstrual cycle abnormalities. This may indicate an association between the growth factors human growth hormone (HGH) and somatomedin-C (Sm-C) and the biosynthese and metabolism of steroid hormone. Recent experiments have demonstrated such associations. Our study showed an association between the HGH and Sm-C levels and abnormal steroid hormone concentrations in women with androgen type PCOD (group I). These patients had a significantly decreased HGH level, a significantly decreased HGH/Sm-C ratio, and an increased average Sm-C level. These data suggest that elevated Sm-C levels can, by a negative-feedback mechanism, inhibit pituitary HGH production. We discuss the possible mechanisms causing elevation of plasma Sm-C, HGH, steroid hormones, excessive food intake, and possibly prolactin seem responsible for the clinical manifestation of increased Sm-C production in adolescence and for its level in the fertile years of patients.

Adult↗
PubMed1990

Inheritance of species-specific behaviors in the paradise fish (Macropodus opercularis): a diallel study.

Species-specific elements of the paradise fish's ethogram were recorded in one familiar and three different unfamiliar environments, which were designed to model certain features of this species' natural habitat: (1) a densely vegetated home range, (2) a novel open field, (3) a small novel place, and (4) a small novel place with a predator. The inheritance of the behavioral elements was investigated employing a five-times-replicated diallel cross among three inbred strains. A detailed Hayman analysis of variance and a variance-covariance analysis were performed to uncover the genetic architectures of these phenotypes. Additive genetic effects and/or ambidirectional dominance was found to be characteristic of most species-specific behavioral elements studied, suggesting an evolutionary history of stabilizing selection.

Animals↗
PubMed1975

Behavior genetic analysis of mouse emotionality. III. The diallel analysis.

A total of 775 pure-strain and F1 mice were obtained from a 6 X 6 diallel mating plan. Previous factor analysis of 42 measures of emotionality identified 14 behavioral factors, ten of which were interpretable. Hayman's analysis of variance and analysis of diallel crosses were applied to each of the factors. In general, the findings indicate that the mode of inheritance for emotionality factors is polygenic and in the direction of complete dominance. However, a major point of this investigation is that the mode of inheritance of highly complex behavior such as emotionality depends on the factor in question. For example, the breakdown of dominance effects by factor was as follows: partial dominance--Motor Discharge, Food Motivation, Tunneling-2, and Activity Level (males); complete dominance--Audiogenic Reactivity, Underwater Swimming (males), and Activity Level (females); overdominance--Acrophobia, Territorial Marking (males). Additional findings include directional dominance for Underwater Swimming and Audiogenic Reactivity, and significant sex differences for eight of the 14 factors.

Animals↗
PubMed1996

Effect of autoclaving on dietary fibre content of beet root (Beta vulgaris). Evaluation by different methods.

Modifications of dietary fibre in beet root during autoclaving have been evaluated by different methods: acid detergent (raw = 1.45%; processed = 1.17%) and neutral detergent (raw = 2.30%; processed = 2.00%), the enzymatic-gravimetric method of Asp (raw = 3.35%; processed = 3.34%), HPLC (raw = 1.42%; processed = 1.60%) and 3,5-dimethylphenol (raw = 0.36; processed = 0.28%). The correlation between different methodologies was studied. Autoclaving was carried out at 121 degrees C under pressure for 15 min. Variance analysis indicated that quantitative variations originating in the thermic treatment were not statistically significant (P > 0.05).

Carbohydrates↗
PubMed1987

[Effect of forced respiration on the stress on puncture channels of sutures in transverse laparotomies of the upper abdomen; experimental studies in the anesthesized dog].

In 11 mongrel dogs in propiophenylpromazine-pentobarbital-anaesthesia the influence of forced respiration on the load of puncture channels of a suture was investigated. For this horizontal suture in the upper abdominal wall, threads No. 3 USP and round needles No. ECT-4 were used. The experiments were carried out in supine position with stretched hindlegs, in supine position with relaxed hindlegs, in lateral position, and in hanging abdominal position. Measurements were performed with a selfconstructed resistance strain gauge element. Rising forced respiration pressure increased the inspiratory load of puncture channels, but there were no significant differences between spontaneous breathing and forced respiration with pressure of 10 cm H2O. In contrary to this there were highly significant differences between spontaneous breathing and forced respiration with pressure of 20 and 30 cm H2O (multiple variance analysis). For instance the load during forced respiration with a pressure of 30 cm H2O in supine position with relaxed hindlegs rose about 67% above pressure values of spontaneous breathing. It could be shown that the expiratory load in the puncture channels was not influenced by forced respiration pressure, but depended on the body position; in dogs it was minimal in side position (45-48 g), higher in supine position with relaxed hindlegs (67-71 g), even higher in supine position with stretched hindlegs (88-92 g), and maximal in hanging abdominal position (109-113 g). By this investigation the increase of load in the puncture channels during forced respiration with pressures of 20 and 30 cm H2O was quantified.

Abdomen↗
PubMed1996

Visual hallucinosis: the major clinical determinant of distorted chromatic contour perception in Parkinson's disease.

Recently distorted chromatic contour perception has been demonstrated in Parkinson's disease (PD). The aim of our study is to determine the clinical factors which influence chromatic contour perception in PD. Chromatic and achromatic contour perception, colour discrimination and clinical data were evaluated in 73 patients with PD. We used a computer-aided method to determine the chromatic fusion time (CFT) which indicates the acuity of monochromatic contour perception. Chromatic CFT was generally shortened in patients as compared to controls (p < 0.01), whereas achromatic CFT was not significantly different. Variance analysis revealed the ability of colour discrimination and the risk of visual hallucinations as statistically significant (p < 0.05) variables influencing contour perception of certain stimuli. In contrast, disease stage, disease duration and disease severity have no relevant effect on chromatic contour perception in Parkinson's disease. On the basis of those properties one may suggest that distorted chromatic contour perception is due to an impairment at a central stage of visual processing in PD and an imbalance of the serotonergic system. Whether CFT is a reliable method to predict the individual risk of hallucinosis in PD has to be evaluated.

Aged↗
PubMed1994

Photometric measurement of pressure-induced blanching of livor mortis as an aid to estimating time of death. Application of a new system for quantifying pressure-induced blanching in lividity.

A newly developed digital system employs photometric measurement of pressure-induced blanching of livor mortis to estimate time of death. The conventional method of applying pressure with thumb or forceps relies largely on subjective interpretation. Our system improves on this method by photometric quantification of color changes produced by defined magnitudes of pressure. We tested the new system by applying increasing levels of pressure to lividity in 50 cadavers with known time of death. Characteristics courses for pressure-induced changes were found for the brightness component of livor mortis, revealing distinct differences between the respective postmortem intervals. The surface areas under these curves were then calculated and distributed into 10-hour postmortem time categories. Variance analysis of these surface values revealed clear differences between the time categories, especially in the medians. Distinct differences between the various postmortem time categories were also evident for the chroma component of livor mortis. The new system offers a further method--in addition to body temperature, rigor mortis, and the electrical responsiveness of skeletal muscles--for estimating time of death, especially after long postmortem intervals.

Equipment Design↗
PubMed1996

The subarachnoid space surrounding the optic nerves. An ultrasound study of the optic nerve sheath.

The presence of enlarged optic nerve sheaths (ONS) suggests that raised intracranial pressure is transmitted to the perineural subarachnoid space (SAS). This phenomenon has gained interest because ultrasound methods are able to quantify the optic nerve sheath diameter (ONSD) in-vivo non-invasively with a resolution below 0.5 mm. In order to study the normal variation and distensibility of the human ONS. Histologic techniques and sonographic measurements were applied to 54 human optic n. specimens before and after exposure to pressure. In untreated postmortem specimens, the largest diameters were found 3 mm behind the globe (baseline range: 2.1 to 4.8 mm). Following volume injection into the orbital perineural SAS, all n. sheaths were enlarged (maximum ONSD 6.5 mm). The sheath expansion affected predominantly its anterior section (mean 1.6 mm, e.g. 50.2%); the posterior regions showed markedly less dilatation (31.6%). No relation was found between the change of ONSD and the baseline diameter. Variance analysis of the sonographic results showed that the observed ONSD change depends on (a) the position of measurement along the nerve, as well as on (b) the origin of the nerve (different/same subject), whereas lateral (left/right) or inter-investigator differences proved negligible. Our results suggest that individual factors determine both baseline sheath diameter and distensibility. The different extent of pressure-induced sheath expansion along the nerve may be partly due to the non-uniform distribution of subarachnoid trabecular fibers between nerve and sheath. In conclusion, measurements of the ONSD for clinical purposes should be targeted to the region immediately behind the globe. Under conditions of raised pressure around the intraorbital optic n., bilateral ONSD measurements should give comparable findings.

Humans↗
PubMedDate not supplied

The impact of daily work load during pregnancy and/or postnatal life on the heart microstructure of rat male offspring.

The microstructure of the cardiac muscle of four groups of male rats was investigated: control (EC) and exercised (EE) offspring of mothers exercised during pregnancy, and control (CC) and exercised (CE) offspring of inactive control mothers. The differences between groups were subjected to variance analysis and multiple range testing according to Duncan. Total body weight did not differ during the entire experiment. With the exception of the subgroup CE (lower values) the absolute and relative (mg/100 g total B.W.) weight of the cardiac muscle did not differ either. The number of heart fibres and capillaries per mm2 was highest in subgroup EE, and significantly lowest in subgroup CC. The capillary: fibre ratio was significantly highest in EE; diffusion distance (D/2) was shortest in EE. Other groups were intermediate. A greater impact of prenatal than postnatal work load on the microstructure of the cardiac muscle of the offspring was demonstrated.

Animals↗
PubMed1994

Circulating soluble intercellular adhesion molecule-1 (sICAM-1) in active inflammatory bowel disease.

Intercellular adhesion molecule (ICAM)-1 promotes the initial interaction between macrophages and T cells during immune activation. We have measured serum levels of soluble ICAM-1 (sICAM-1) by ELISA in 27 patients with ulcerative colitis (UC), 31 with Crohn's disease (CD), and 29 healthy subjects. The median sICAM-1 serum concentration was significantly increased in inflammatory bowel disease (IBD) patients (355 ng/ml, range 195-855) compared to controls (245 ng/ml, 155-580) (P = 0.001). Variance analysis for trend showed that sICAM-1 levels were significantly higher in patients with active CD and UC, compared to those with inactive disease and controls (P = 0.00002). The concentration of sICAM-1 was higher in CD patients (365 ng/ml 230-470) compared to UC (300 ng/ml 195-855) (P = 0.01). Furthermore, weak but significant correlations were found between serum levels of sICAM-1 and: soluble IL-2 receptors, orosomucoid, and C-reactive protein. It is suggested that increased circulating sICAM-1 levels may reflect increased adhesiveness and signal transmission across cells, probably as a result of shedding of the parent molecule during local cellular immunoresponses in vivo.

Acute-Phase Proteins↗
PubMed1992

Do motor evoked potentials allow quantitative assessment of motor function in patients with spinal cord lesions?

Motor evoked potentials (MEP) were recorded in a total of 110 patients with tumorous (n = 39) and non-tumorous (n = 71) lesions of the cervical (n = 59), thoracic (n = 37) and thoracolumbar (n = 14) spinal cord. In all cases MEP were elicited by electrical stimulations, and in 50 of them also by magnetoelectric stimulation, of the motor cortex. The peripheral conduction time was determined by electrical stimulation of the lumbar nerve roots. It was the aim of this study to determine whether 1. MEP are sensitive for detection of lesions along the spinal cord and 2. whether they allow quantitative assessment of motor function. To achieve this goal, we compared potential and clinical findings of our patients, each divided into seven categories. Our results clearly showed the high sensitivity of MEP for semi-quantitative evaluation of motor function, as there were no false negative results in our series. Moreover, unilaterally accentuated motor deficits correlated significantly with changes in MEP, which were affected more strongly on the corresponding side (Student's t-test, alpha = 0.05). However, clinical and electrophysiological findings did not correlate in the quantitative evaluation of the motor status as established by variance analysis (F = 0.52). There was no difference in results with respect to the electrical and magnetoelectric stimulation technique. Our results lead to the following conclusions. MEP are sensitive for semi-quantitative evaluation of spinal motor function; however, MEP do not allow quantification of the clinical motor status.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗