Sensation Seeking and Cortical Augmenting-Reducing

The experiment was designed to establish the relationship between the Sensation Seeking Scales (SSS) and cortical augmenting-reducing. Forty-nine male undergraduate Ss were used. Ss were presented with five intensities of light flashes in randomly presented blocks of trials at each intensity. Averaged evoked response (AER) amplitudes were measured at each intensity of light. Augmenting-reducing was measured for each S as the slope of the relationship between stimulus intensity and amplitude of response. This slope measure correlated very significantly (r= .59) with the Disinhibition subscale of the SSS and positively, but not significantly, with other subscales. Comparing the low and high scorers on the Disinhibition scale, a significant interaction between groups and stimulus intensities was found but no main effects of stimulus intensity or groups were found. The high Disinhibitors did not differ from the lows at the low stimulus intensities but did differ significantly at the highest intensity where the lows showed a marked reducing tendency. The results show an interesting convergence between the Disinhibition type of sensation seeking, manic tendencies, and the AER.     

Cancer of the colon in an egg donor: policy repercussions for donor recruitment

This paper describes the tragic case of a young woman who died of cancer of the colon after successfully donating eggs to her younger sister. Although there is no direct link between her operation and the subsequent development of bowel carcinoma, this case imparts a feeling of unease when seen in conjunction with other cases reported during the last few years. It is a reminder that little is known of the long-term consequences of some aspects of assisted conception. Women undergoing ovarian stimulation for themselves or a matched recipient have the right to be advised, in an agreed format, that there is some concern about unproven potential risks from the stimulatory drugs. The safety of egg donors must assume priority over all other considerations, including lack of donors or any moral position. The recent decision by the Human Fertilisation and Embryology Authority (HFEA) to withdraw any form of payment or recompense to egg donors does not seem to us to be based on a balance of scientific advances, patient needs and the ethics of gamete supply. They state that the intention to withdraw payments was implicit in the 1990 Human Fertilisation and Embryology (HFE) Act. However the Act was based on the Warnock report made 6 years earlier. Even in 1990 ovum donation was uncommon and fertility drugs had not yet caused any unease. The Act provided the HFEA with discretionary powers to issue directions so that the future policies would be consistent with any emerging new medical evidence. It is imperative that the HFEA provide convincing evidence on how the current policy of payment to donors harms society, donors or recipients, and how in the UK the new policy will improve medical practice in assisted conception. Successful pilot studies must precede the implementation of any new policy. Failure to do this could cause irreversible harm to the practice of assisted conception using donor gametes, which will ultimately be against the basic aims of the 1990 HFE Act.      

Development of Coombs positive haemolytic anaemia in NZB mice injected with Freund's complete adjuvant

Intraperitoneal injection of young adult NZB mice with Freund's complete adjuvant emulsion, alone or incorporating BALB/c mouse erythrocytes, resulted in accelerated direct Coombs conversion and development of splenomegaly. Incorporation of adjuvant with NZB erythrocytes caused an accelerated reactivity in some animals, but in others resulted in a delayed Coombs conversion. In contrast, positive Coombs tests failed to develop at all in NZB mice injected with a Freund's complete adjuvant preparation containing ten times the usual amount of Mycobacterium. These observations might be explained in part by the relative influences of adjuvancy and of antigenic competition on the availability of precursor cells capable of responding to autoantigenic stimulation.     

Life and death decisions: secondary complexes and lipid rafts in TNF receptor family signal transduction

Signaling by receptors in the TNF receptor (TNFR) superfamily mediate biological outcomes ranging from inflammation to apoptosis and other forms of programmed cell death. How receptor signaling mediates these divergent responses is just beginning to be understood. Here, we discuss how receptor submembrane localization and the formation of alternate signaling complexes can alter the fate of cells stimulated through TNFRs with a death domain, also known as "death receptors."     

Blutdruck,relatives Körpergewicht,Alkoholkonsum und Elektrolytausscheidung in der BRD und der DDR: Die Intersalt-Studie

Summary The relationships between body mass index (BMI) and age, alcohol consumption, 24-hr urinary electrolyte excretion, and BP were studied in 588 subjects from three German centers participating inIntersalt, a highly standardized, previously reported protocol. Men and women aged 20–59 were sampled in Bernried, FRG; Cottbus, GDR; and Heidelberg, FRG. The subjects from the three centers did not differ in BMI, level of education, physical activity, cigarette- or alcohol-consumption patterns, or urinary Cl excretion. Mean Na excretion was 167, 147, and 172 mmol/24 hr in Bernried, Cottbus, and Heidelberg, while mean K excretion was 72, 55, and 73 mmol/24 hr, respectively. The excretion of these electrolytes was significantly lower in Cottbus than in Bernried or Heidelberg. BMI increased progressively in men with age; in women BMI plateaued until the 5th decade, after which it increased to equal that of men. In individual centers, the excretion of electrolytes was correlated with BML Sodium and chloride excretion were highly correlated. The data from each individual center were fitted to a multiple regression model. Age, BMI, sex, and alcohol consumption entered the model.

     

Genetic analyses of gustation in the fowl

Preferences towards quinine sulfate (QS) and dextrose (DEX) were tested in purelines and reciprocal crosses of two lines of chickens that had undergone 22 generations of selection for high and low juvenile body weight. Parental line-F₁ comparisons provided evidence for non-additive genetic variation for hedonic sensitivity towards QS and DEX, though in opposite directions. Additive genetic variation appeared to influence the preference ratios for both stimuli at super-threshold concentrations. These results are discussed with regard to their evolutionary implications.     

Cephalic-phase insulin secretion in normal and pancreatic islet-transplanted rats

The ability of saccharin, in comparison with glucose and tap water, to elicit glycemia-independent neurally mediated insulin secretion was investigated in chronically catheterized, freely moving rats. Plasma glucose and insulin concentrations were measured continuously from venous blood with a sampling resolution of one per minute. In normal rats, 1 ml of 0.15% saccharin caused a significant rapid rise in peripheral plasma insulin levels lasting up to 5 min, without significant changes in glycemia. Tap water alone also induced a transient elevation in insulinemia but was much smaller than the saccharin-induced response. In streptozotocin diabetic rats bearing intrahepatic, presumably denervated islet isografts, these rapid insulin responses to oral saccharin and tap water stimulation were completely abolished, whereas the early insulin response to intravenous glucose was decreased by only about 30%. These results are consistent with the concept of gustatory and other oral sensory signals acting as triggers for neurally mediated insulin release.     

The interaction of lymphocytes with autologous red cells

There is a relatively large degree of adherence of rabbit thymocytes to autologous or homologous mature and nucleated red cells, but not to heterologous red cells. The adherence is augmented by sera and a variety of protein solutions. It is inhibited by 4 × 10⁻³M iodoacetate or pretreatment of red cells by 0.01 to 0.5 per cent trypsin solution. Thymocytes obtained from one- to 7-day-old rabbits adhere to rabbit red cells to a larger extent than do thymocytes of adult rabbits. Significant autologous or homologous thymocyte-red cell adherence also occurred in the rat but not in the mouse or guinea pig. Heterologous adherence was not evident except in mixtures containing guinea pig thymocytes and rabbit red cells or mouse thymocytes and rat red cells. It is postulated that the adherence of thymocytes to the red cells occurs through nonimmune mechanisms and that it is likely to affect the homing patterns of the lymphocytes.     

Immunohistochemical localization of apolipoproteins A-I and B in human carotid arteries

Decreased plasma levels of apolipoprotein A-I (apo A-I) and increased plasma levels of apolipoprotein B (apo B) have been shown to correlate with increased risk of atherosclerosis. While many studies have investigated the plasma levels of these apolipoproteins with regard to their value as predictors of cardiovascular disease, comparatively little is known about their precise tissue localization in atherosclerotic plaques. The purpose of this study was to determine the tissue localization of apo A-I and apo B in atherosclerotic segments of human carotid arteries through the use of immunohistochemical techniques. With tissue samples obtained from surgery and autopsy, apo A-I and apo B were found to be present in atherosclerotic plaques and absent in normal arterial tissue. In the plaques, both apo A-I and apo B were found extracellularly, primarily in the lipid core, but also in connective tissue. In addition, both apo A-I and apo B were found intracellularly in foam cells. This similar intracellular and extracellular distribution of apo A-I and apo B was unexpected, in view of their differing associations with atherosclerosis.     

A placebo-controlled trial of procaterol: A new long-acting oral beta2-agonist in bronchial asthma

Procaterol hydrochloride, a potent beta 2-adrenergic bronchodilator developed in Japan, was evaluated in a double-blind, placebo-controlled study for efficacy and safety in 45 patients (ages 18 to 55 yr) with chronic documented reversible airway disease. After a 1-week placebo washout period, patients were administered either 0.05 mg or 0.10 mg of procaterol or placebo twice daily for 2 wk. Spirometric determinations, vital signs, and ECGs were obtained at 1/2, 1, 2, 4, 6, and 8 hr after the first dose and at the same time intervals after 1 and 2 wk of treatment. Patients recorded on a daily basis peak flow rates, asthma symptoms, need for supplemental aerosol, concurrent medications, and side effects. Spirometry results indicated significant improvement in pulmonary function with both doses of procaterol compared with placebo (P less than 0.05). The larger dose was generally more effective. Bronchodilatation was evident 1/2 hr after dosing and peaked at 2 hr. At 8 hr after 0.10 mg of procaterol, FEV1 was still above predose values. Daily peak flow rates were significantly higher with 0.10 mg than with 0.05 mg (P less than 0.05) and placebo (P less than 0.001). Tremor and nervousness were the most frequent side effects. They occurred in a dose-related frequency, were mild and transient, and occurred early in treatment. No significant drug-related changes were noted in ECGs, heart rate, blood pressure, or clinical laboratory data. Procaterol was found to be an effective, well-tolerated oral bronchodilator with a long duration of action, especially at 0.10 mg twice daily.