PubMed Health⌕ Search

Biomedical subjects

C Spring

Publications and source records attributed to C Spring.

15 recordsLinked to original sources

Modification of spontaneous contractility of smooth muscle preparations from the bovine abomasal antrum by serotonin receptor agonists.

The effects of serotonin (5-hydroxytryptamine, 5-HT), a 5-HT2-receptor agonist, alpha-methyl-5-hydroxytryptamine (alpha-M-5-HT) and RS-67506, a 5-HT4 receptor partial agonist, on spontaneous contractility of bovine abomasal smooth muscle preparations were investigated in vitro. Preparations from the abomasal antrum of freshly slaughtered healthy dairy cows were cut parallel to the longitudinal fibres, suspended in isolated organ baths, and concentration-response curves were performed by cumulative application of the 5-HT receptor agonists. Blockade of 5-HT2-induced response was tested with atropine and hexamethonium. Serotonin evoked a significant increase in the area under curve (AUC), whilst the 5-HT2 receptor agonist alpha-M-5-HT significantly increased the AUC and resting tone (RT). RS-67506 induced a significant increase in AUC and RT and a significant decrease in the maximum force. The effect of alpha-M-5-HT was mediated by a muscarinic cholinergic pathway, as the effect of alpha-M-5-HT was inhibited in the presence of atropine but not hexamethonium. It is concluded that 5-HT2 and 5-HT4 receptors are present in the bovine abomasal antrum. Muscarinic receptors are involved in the increase in RT seen after 5-HT2 receptor stimulation.

Abomasum↗

Effect of moisture content on the invertase activity of freeze-dried S. cerevisiae.

The invertase activity of intact Saccharomyces cerevisiae submitted to freezing-thawing was affected by pH, the chemical nature of the buffer, and the freezing cooling rate (CR), leading in some cases to a complete invertase inactivation (acetate buffer, pH 4.0, CR = 0.5 degree C/min). Once established under adequate freezing conditions the invertase activity remained unchanged after freeze-drying. Nevertheless, in some cases the cell-growing capability after freeze-drying diminished around 70%, mainly if the frozen cell suspension was attained through freezing carried out at CR = 0.5 degree C/min. Water sorption isotherms of freeze-dried samples (freeze-dryer Edwards L-4KR; 30 degrees C and 0.1 mB) were determined at 10 and 25 degrees C. The monolayer moisture content (MMC) at each temperature (12.7 and 3.71 for 10 and 25 degrees C, respectively) was calculated from isotherms by applying BET and GAB models. Freeze-dried yeast with water activity (Aw) between 0 and 0.33 (about the MMC value) maintained at 25 degrees C for 235 days and at 89 degrees C for 15 min retained at least 85% of its original invertase activity (IA), whereas samples with Aw > MMC lost at least 60% of its IA. X ray diffraction showed that the freeze-dried cake before and after storage presented an amorphous structure.

Buffers↗

Identifying children with specific reading disabilities from listening and reading discrepancy scores.

A method of identifying children with specific reading disabilities by identifying discrepancies between their reading and listening comprehension scores was validated with disabled and nondisabled readers in Grades 4, 5, and 6. The method is based on a modification of the reading comprehension subtest of the Peabody Individual Achievement Test (Dunn & Markwardt, 1970). In this modification, even-numbered sentences are read by subjects, and odd-numbered sentences are read by the test administrator as subjects listen. The features of this test that reduce demands on working memory, thereby making it suitable for the detection of a discrepancy between reading and listening comprehension in readers with disabilities, are discussed. A significant group-by-modality interaction was obtained. Children with reading disabilities scored significantly lower on reading than on listening comprehension, while nondisabled readers scored slightly higher, but not significantly so, on reading than on listening comprehension. The appropriateness of this method as a substitute for the traditional method, which is based on the detection of a discrepancy between intelligence and reading and which has recently been proscribed in certain school districts, is discussed. Issues concerning the listening comprehension skills of disabled readers are also discussed.

Child↗

[The mouth-plate, an aid in respiratory treatment in intensive care units (author's transl)].

The mouth plate is a new auxiliary device used in respiratory therapy. It is applied to patients who cannot adapt to conventional mouth pieces owing to different anatomical-functional difficulties. Easy clinical application and the air tight effect of the mouth plate permitted efficient respiratory therapy with IPPB in 20 cases with the mentioned difficulties so that some would not need more invasive measures such as endotracheal intubation or even mechanical ventilation. Other possible application in the intensive care unit and also in emergency medicine are mentioned briefly.

Adolescent↗

[A system for "intermitten mandatory ventilation" (IMV) using the engström respspirators ER 200/300 (author's transl)].

At low financial and material costs conventional Engström-respirators (Types ER 200, 300) can be converted to make Intermittent Mandatory Ventilation (IMV) possible. These so converted respirators were examined when a group of patients in a surgical intensive care unit who had undergone mechanical ventilation for a longer period of time was weaned from the respirator. It could be shown that during the step-by-step weaning of these patients no significant changes appeared in the results of the blood gas analyses, which means that the patients' pulmonary function took over again gradually. Doubtlessly, the convertability of the Engström-respirator for IMV will help promote the weaning of patients with respiratory complications by this method.

Intensive Care Units↗

Agreement of mothers' and teachers' hyperactivity ratings with scores on drug-sensitive psychological tests.

Hyperactivity ratings were obtained from parents and teachers for 45 hyperactive, children. The children were also given several psychological tests. Teachers' ratings, but not parents' ratings were negatively correlated with performance on the psychological tests that require sustained attention and on which performance is improved by stimulant drugs. This pattern of correlations was interpreted as evidence that teachers, but not parents, have an opportunity to observe children performing daily tasks that require sustained attention.

Attention↗

Effects of imipramine and methylphenidate on perceptual-motor performance of hyperactive children.

Perceptual-motor effects of imipramine and methylphenidate were evaluated in a double-blind study of 47 hyperactive children. No effects were found for imipramine, although methylphenidate improved performance on several tests. Improvement due to methylphenidate was not related to base-line scores. A discriminant function was computed to compare baseline perceptual-motor scores of the hyperactive and 41 normal children. Only half of the hyperactive children were clearly discriminated from normal children by the discriminant function. The digit-span test, which was not sensitive to methylphenidate, effectively discriminated hyperactive from normal children.

Adolescent↗