Mechanism for polarisation of cardiac tissue at a sealed boundary

If current is flowing in cardiac tissue, and if the myocardial fibres approach a sealed boundary at an angle, then the tissue within a few length constants of the boundary is polarised. This polarisation occurs when the cardiac tissue has different anisotropy ratios in the intracellular and extracellular spaces. This new mechanism of tissue polarisation is demonstrated using a simple, analytical model, and it is shown quantitatively that this polarisation can be nearly as large as that occurring near an electrode.     

A gamma camera for measurements of internal contamination after a radiological accident.

After a radiological accident with the release of large amounts of radionuclides into the environment, measurements of the external and internal exposure of the public will be urgently required. The aim of this study was to investigate the properties of a gamma camera with regard to measurements of internal contamination. The gamma camera was used as a detector without any imaging function. The lowest minimum detectable activity, 100 Bq 131I in thyroid measured over the neck and 400 Bq 137Cs in the whole body measured over the trunk (1 min measuring time), was found when using the lowest (50 keV-450 keV) energy interval among the three investigated (also 550-750 keV and 450-550 keV), in measurements without a collimator. The mechanical difficulties in handling a gamma camera without a collimator may also have to be considered. It is essential to pay attention to the influence of body size on both background and sensitivity. Provided proper calibrations are carried out and routines for measurements are established, a gamma camera is useful for fast identification and quantification of internal contamination with gamma-emitting radionuclides down to levels so low that in most situations they give a low contribution to the effective dose.     

Restraint-induced stress ulcer. I. Hypothalamic,urinary, and adrenal biochemical studies

The purpose of these experiments was to study the incidence of stress ulcers in restrained rats and to correlate it with hypothalamic and adrenal cortical and medullary activity, with and without vagotomy. A total of 217 adult rats were used, grouped into 56 sets, and distributed at random in 5 experimental groups. Restraint was followed by a 79% incidence of ulceration in the glandular portion of the gastric mucosa. Vagotomy made these worse (p<0.01). Hypothalamic levels of catecholamines and serotonin showed no significant changes. Urinary measurements revealed decreased excretion of 17-ketosteroids (p<0.001), increased excretion of uropepsinogen (p<0.01), and no significant changes in vanillylmandelic acid among the rats submitted to immobilization. In the adrenal glands of stressed animals, there was a decreased level of catecholamines (p<0.01) and no significant changes in corticosteroid content (17-ketosteroids). These results suggest that hypothalamic stimulation and the participation of the adrenal glands are not essential factors in the pathogenesis of restraint-induced experimental stress ulcer.     

A new method for evaluation of the acrosome reaction in viable human spermatozoa

The acrosome reaction of human spermatozoa was induced by changes of temperature. Spermatozoa were collected from fertile donors and a patient group, and selected by the "swim-up" method. The spermatozoa were treated in two different ways: Protocol I: 24 hours at room temperature followed by additional incubation at 37 degrees C for 3 hours (control), and protocol II: 24 hours at 4 degrees C followed by additional incubation at 37 degrees C for 3 hours. The acrosome reaction of the viable spermatozoa was evaluated by a new method utilizing indirect immunofluorescence with anti-outer acrosomal membrane antibodies and exposure to a hypo-osmotic medium. In fertile donors as well as in the patient group, significant induction of the acrosome reaction (20%) was evident after exposure to low temperature (4 degrees C). The spontaneous rate of acrosome reaction in the control group was below 7%.     

Hemodialysis in schizophrenia

Summary Therapeutic trials with hemodialysis have been performed in three cases of chronic schizophrenia. The severely ill patients had been hospitalized for more than ten years and had not responded to different types of conventional somatic treatment. Psychopathology was evaluated by use of the IMPS, BPRS, and NOSIE scales. No improvement could be observed as a consequence of 12 (11 in one case) hemodialysis treatments. Rather, some deterioration occurred in two of the patients. This result is not in accord with the markedly positive findings of Wagemaker and Cade (1977). However, further studies appear necessary to render final conclusions.Supported by a Stipendium of the Fritz-Thyssen-Foundation, Cologne     

Precancerous lesions of the stomach

The etiology of stomach cancer in relation to preexisting mucosal alterations is described and discussed from a review of the literature and our own previously reported experience. The incidence of cancerization or malignant change of gastric polyp, chronic gastric ulcer, and chronic gastritis varies considerably from researcher to researcher. Clinical follow-up studies in many cases of gastric polyp and chronic ulcer discovered in the mass survey examination of the stomach revealed incidences of malignant degeneration of 2.3% of the gastric polyp cases and 2.06% of the gastric ulcer cases.

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Résumé Les relations entre altérations préexistantes de la muqueuse et étiologie du cancer gastrique sont décrites et discutées, avec revue de la littérature et de notre expérience personnelle. La fréquence des cancérisations ou des dégénérescences malignes des polypes gastriques, de l'ulcère gastrique chronique et de la gastrite chronique est éminemment variable d'une étude à l'autre. Les follow-up de populations soumises à des examens systématiques de dépistage indiquent que la fréquence des dégénérescences malignes est de 2.3% pour les polypes gastriques et de 2.06% pour l'ulcère gastrique.

     

Lung contamination among foundry workers

Summary Ten iron foundry workers representing typical foundry occupations were examined. The amount of lung contamination was estimated after the workers' thoracic area had been magnetized and the remanent magnetic field measured. Chest radiographs were classified according to the siderotic, silicotic, and nonspecific changes found; and the changes were then divided into four categories.The preliminary results of the electron micrographs indicated that the size and shape of the pollutants varied greatly according to the type of foundry site. In addition, the estimated amount of lung contaminants in the subjects varied between 30 and 600 mg. A good correlation (r=0.86) was obtained between radiological siderotic and silicotic changes, and the correlation between both of these radiological findings and the measured average permanent magnetic field was rather good (r=0.60). There was no correlation between the estimated exposure (neither length nor magnitude) and the amount of retained lung contaminants, and therefore a balance between retention and clearance seemed to have been achieved. These results indicate that the magnetic measuring method can be used to evaluate the amount of lung contaminants retained by foundry workers.     

Comparison of postoperative complications following radical and modified radical mastectomy

A retrospective study was carried out by reviewing the files of 100 patients who had undergone radical mastectomy and 100 patients who had undergone modified radical mastectomy from 1966 to 1975 for the purpose of comparing early and late complications. In each group, 80 patients were involved in long-term follow-up. Immediate postoperative complications—notably seromas, wound infection, and flap necrosis—were found to be considerably fewer following modified radical mastectomy. There was also a significantly lower incidence of late complications, such as limb edema and recurrent infection, after modified radical mastectomy. Since the cure rates achieved by the two radical mastectomy procedures appear to be similar, it is concluded that modified radical mastectomy is the procedure of choice in stages I and II cancer of the breast.

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Résumé Nous avons relevé les dossiers de 100 patientes traitées par mammectomie radicale conventionelle et de 100 patientes traitées par mammectomie radicale modifiée et avons comparé les complications post-opératoires observées dans les 2 groupes. Toutes les patientes furent opérées entre 1966 et 1975. Dans chaque groupe, nous avions un recul suffisant chez 80 patientes pour évaluer les résultats à long terme. Les complications post-opératoires, immédiates (sérÔmes, infections de plaie, nécrose de greffe cutanée) ou tardives (lymphoedème du bras, infections à répétition), furent beaucoup plus rares après mammectomie radicale modifiée. Etant donné que les taux de guérison obtenus avec ces 2 opérations semblent Être les mÊmes, nous en concluons que la mammectomie radicale modifiée est l'opération de choix pour traiter les cancers du sein au stade I et II.