Respiratory rhythmically regulated electrical stimulation of paralyzed laryngeal muscles

Electrical stimulation of the posterior cricoarytenoid muscle, synchronized with inspiration, was achieved in dogs, utilizing a radio frequency stimulus triggered by a chest wall expansion transducer. This system brings about the abduction of the paralyzed vocal cord for the entire duration of inspiration, which allows a normal flow of air through the larynx. The stimulation system could be tested successfully in actual experiments in dogs with artificial paralysis of the recurrent laryngeal nerve. Its effectiveness could be proved through observation of the vocal cord movements (photographic documentation) and recording subglottic pressure variations. Transmission of stimulation energy is effected by electrical induction.

Effect of family relationships on psychogeriatric patients

Severe strain has been repeatedly reported in the families of psychogeriatric patients. Nevertheless, many families continue to provide a great deal of support, despite the undoubted burden involved. A retrospective study of short-term outcome in 60 psychogeriatric referrals demonstrated the importance of some aspects of the relationship between the patient and their key supporting relative. In the sample as a whole, and in functional patients, the extent to which a positive communication system existed was significant. In patients with dementia, poor outcome was related to the patient being less dependent and more dominant in their interaction with the relative. The implications of this study for intervention and future research are discussed.

On sources of error in the biochemical study of perilymph (guinea-pig)

Contamination of perilymph with other fluids (cerebrospinal fluid, tissue fluid, blood, endolymph) together with sampling, anaesthesia, surgical intervention or food intake of the animals may considerably affect the analytical result. The numerous possible artefacts seem to be the main reason why varying values are given in the literature for the same chemical component of perilymph. This is also partly true of cerebrospinal fluid and blood. The effect of some sources of error on selected chemical components of perilymph, cerebrospinal fluid and blood is briefly summarized.

[Total lactate dehydrogenase activity of perilymph, plasma and cerebrospinal fluid in unstressed and noise stressed guinea pigs]

The total activity of lactate dehydrogenase (LDH) of perilymph (PL), plasma, and cerebrospinal fluid (CSF) of unexposed and sound-exposed guinea pigs was examined with due consideration of the principal sources of error. To test the purity of PL samples, protein, potassium, and sodium were determined simultaneously (Table 1). The LDH was analysed fluorometrically. It was found that there are considerable differences in the LDH activities of PL, CSF, and plasma (Table 2). The mean activity of PL was three to four times higher than that of CSF and only about half that of plasma. No significant difference was found between the PL in scala tympani and scala vestibuli. The most frequent LDH values of the individual fluids (Fig. 2) were somewhat lower than the mean values calculated. Immediately (less than or equal to 60 min) after exposing the animals to wide-band noise at an intensity of 140 dB SPL for 10 min, the mean PL values of the scala tympani and scala vestibuli were found to be somewhat higher than in unexposed animals (Table 3). Eighteen hours after the exposure, slightly higher activity was only detectable in PL of the scala vestibuli. The differences were not found to be significant. The LDH values of CSF and plasma remained unchanged both less than or equal to 60 min and 18 h after noise exposure.

[Obesity in childhood]

It is impossible to make general statements on obesity, and apply them to all adipose patients. These statements can be more or less valid for various populations of obese subjects depending on the definition of obesity chosen. Obesity in infancy should not be disregarded, although it has not been proven that obese infants become obese adults, whereas obese adolescents tend to remain obese. Obesity is genetically determined yet exogenous factors are more or less necessary for its development. The significance of risk factors changes during childhood, depends on the gender, and varies with different populations. The hypothesis that obese patients have a diminished thermogenesis should be considered although it is not clear whether this applies to all obese patients. Research on disregulation of appetite could result in further clarification of the pathogenic mechanism causing obesity. Treatment of obesity is necessary in patients with 120% or more overweight related to height, preferably before age of 7 years to take advantage of further growth as a regulating factor.

Influence of genes associated with the main histocompatibility complex on deoxyribonucleic acid excision repair capacity and bleomycin sensitivity in mouse lymphocytes

In sets of mice congenic at H-2 and upon two backgrounds, and selected according to known differences in strain-specific lifespans, DNA repair efficiency in spleen cells was compared by two techniques: excision repair capacity following UV-irradiation, and bleomycin sensitivity. Significant differences between certain congenic partner sets were noted with both techniques, suggesting that the main histocompatibility complex influences DNA repair capacity.

Membrane receptors and their redistribution in lymphoproliferative disorders

Lymphoid cells from 20 patients with lymphoproliferative disorders, including chronic lymphocytic leukemia, hairy cell leukemia, Sezary syndrome, lymphoma, and lymphadenitis, were studied for redistribution of surface membrane immunoglobulins (SmIg) and concanavalin A (Con-A) receptors. Fluorescein-labeled polyvalent goat anti-human immunoglobulin and fluoresceinated concanavalin A were used as ligands. Results were similar with both ligands. The highest percentage of capping of ligand-membrane receptors was noted in mononuclear cells from patients with "hairy" cell leukemia: from 24% to 90%. These cells showed moderate to marked fluorescein activity and were able to cap within 15 min at 4 degrees C. Chronic lymphocytic leukemia cells showed a weak fluorescein stain with a very low percentage of cells (0%--16%) capping. Lymph node cells from patients with lymphoma demonstrated moderate to strong fluorescein activity with only an average of 3% of the cells capping; while lymphoid cells from patients with lymphaedenitis showed an average of 27.5% capping and moderate fluorescein activity. Capping of Con-A receptors in mononuclear cells from patients with Sezary syndrome was poor (0%--14%) with moderate fluorescein intensity. This report demonstrates difference in density and mobility of binding sites for SmIg and Con-A on the surface membrane of lymphoid cells from various subclasses of lymphoproliferative disorders. These differences may assist in the differential diagnosis and classification of these conditions.