Perinatal mortality in Marondera district

In an attempt to identify factors associated with stillbirths and those occuring in the 1st week of life, perinatal deaths in infants born in health facilities in Marondera Districts occurred during a 7 months period 1986 were recorded and analyzed. 66 such deaths out of a total of 1900 births, giving a perinatal mortality rate of 35/1000 total births. The largest groups with identifiable cause were intrapartum asphyxia (14 deaths) and severe prematurity (birthweight 1500 gm) (8 deaths). The other associated causes of perinatal deaths were antepartum hemorrhage, code prolapse, toxemia of pregnancy, ruptured uterus, severe congenital abnormalities and intrauterine infections.     

The role of microfilaments in the healing of the corneal endothelium

Actin microfilaments are presumed to play a role in cell locomotion. The function of these filaments may be selectively suppressed by cytochalasin. A dose-dependent delay of the repair of a corneal endothelial defect by the application of cytochalasin in tissue culture has been observed by SEM. This observation confirms that the actin microfilaments are important for the endothelial repair.     

Intraoperative and Immediate Postoperative Management of Calves Undergoing Valve or Total Artificial Heart Implantation

The intraoperative and immediate postoperative management data were recorded in a series of twelve artificial device implantation operations in calves. Nine of these were valved conduit experiments not requiring cardiopulmonary bypass, and three were total artificial heart implantations in which bypass was needed. The intraoperative and immediate postoperative management procedures of this laboratory are described including anesthesia, respiratory and drug therapy, and cardiopulmonary bypass management. This paper shows how these procedures may aid in reducing the recovery times of research animals.     

Occupational causes of laryngeal cancer.

In a case-control study of all new cases of laryngeal cancer in Denmark from 1980 to 1982, 326 cases and 1134 community selected controls participated. Questionnaires were used to obtain information on education, occupation, and number of occupational exposures as well as smoking and drinking habits. High risk ratios for laryngeal cancer were found for semiskilled and unskilled workers, workers exposed to dust, out of doors workers, drivers, and people working in the cement industries and port services. The study hypothesis was that exposure to chromium or nickel increases the incidence rate of laryngeal cancer. No support for this was found concerning chromium, but exposure to nickel had a statistically significant risk ratio of 1.7.     

Smoking and ciliary movement in the upper respiratory tract

Summary Using the microphoto-oscillographic method for recording ciliary activity in the respiratory tract we studied ciliary function in a group of normal persons and in patients having various laryngeal diseases. We tried to assess ciliary activity in heavy smokers versus moderate smokers/non-smokers. Like previous authors we found ciliary activity to be reduced or totally abolished in moderate and in heavy smokers. The possibility of the carcinogenic effect of cigarette smoking is discussed in the light of the reduced ciliary activity. Heavily soluble carcinogens trapped in the bronchial mucosa will thus be able to remain in contact with this mucosa for a long time and exert their action.

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Zusammenfassung Die Aktivität der Cilien der Atmungswege wurde an einer Gruppe normaler Personen und einer mit schweren Kehlkopferkrankungen mittels der Mikrophoto-Oseillographie untersucht. Bei dem Versuch, die Cilienaktivität starker Raucher gegenüber mäßigen und Nichtrauchern zu vergleichen, fanden wir wie vorangehende Autoren die Aktivitat bei gemäßigten und schweren Rauchern vermindert oder völlig aufgehoben. Die Möglichkeit eines carcinogenen Effektes des Zigarettenrauchers wird in bezug auf die verminderte Cilientdtigkeit diskutiert. Schwerlösbare Carcinogene, die auf die Bronchialschleimhaut gelangen, können so lange Zeit mit der Schleimhaut in Kontakt bleiben und ihre Wirkung ausüben.

     

Thrombus generation within the artificial heart.

The sites of thrombus formation in the Jarvik III artificial heart were studied in 20 consecutive calf experiments. Identical design and implantation procedures were used with two different surfaces. The 10 anticoagulated calves receiving Dacron-fibrilized silicone rubber surfaces survived an average of 296 hours. In contrast, the 10 nonanticoagulated calves with smooth poyurethane hearts survived 545 hours. The polyurethane surfaces were constantly clean. However, the rough surfaces were coated with variable amounts of thrombi. The sharp angle between the diaphragm and housing contained varying amounts of thrombi deposits in 75 per cent of the cases. Thrombe deposition occurred on 41 per cent of the valves. These thrombe were the source of emboli into the kidney, brain, and lungs. Turbulences and stagnation areas generated thrombus formation. Anticoagulation did not prevent thrombus formation. It would appear that heart free of turbulence and stagnation areas must be designed to eliminate thromboembolism.     

Effect of exercise on oxygen consumption, heart rate, and the electrocardiogram of pigs

Pigs were exercised for 5 min at five different treadmill speeds (1.0-1.8 m X s-1) (3 degrees incline), while oxygen consumption (MO2), carbon dioxide production (MCO2), and the electrocardiogram (ECG) were recorded continuously. Data were taken at rest, during exercise, and at 2, 5, 15, and 30 min after exercise. Values for MO2, MCO2, and heart rate (HR) showed progressive increases with increasing treadmill speed. The respiratory exchange ratio (R) increased during exercise and approached 1.0, but peak values were seen shortly after exercise. Heart rate, MO2, MCO2, and R reached steady-state values after 2 min of exercise, which were maintained for the duration of exercise. In most cases, these variables had returned to control levels 15 min after exercise. A high correlation between HR and MO2 was found in these animals. Prominent increases in T-wave amplitude of the ECG were associated with exercise and early recovery. The metabolic and cardiac changes associated with exercise in these animals were all qualitatively similar to responses seen in exercising humans. Thus, this study further supports the belief that the pig is a good model for studying the cardiopulmonary responses to exercise in humans.     

Risk of nonocular cancer among retinoblastoma patients and their parents. A population-based study in Denmark, 1943-1984

The risk of nonocular cancer among survivors of retinoblastoma has been investigated in a population-based study in Denmark, 1943 to 1984. None of the survivors had been treated with chemotherapeutic drugs. Forty-eight patients were treated with x-rays, and 102 patients were treated primarily with surgical removal of the eye(s). The overall relative risk (RR) for a new primary cancer was 4.2 (95% confidence limits, 1.1-11.5). In the subgroup of genetic retinoblastoma the risk was 15.4 (95% confidence limits, 2.6-50.8) and in the group of nonhereditary cancer the risk was 1.7 (95% confidence limits, 0.1-8.5). For all retinoblastoma patients the RR of bone cancer was 100 (95% confidence limits, 17-330). Parents not having retinoblastoma themselves were not at increased risk for nonocular cancer.     

Cholecystectomy rate in autopsies from a Danish urban area. Frederiksberg 1914-1987

A review of 7,647 autopsies performed in 1914-1987 on 3,629 women and 4,018 men aged 50-79 years in a Danish urban area demonstrated significant increase in the rate of cholecystectomy (p less than 10(-3] for men and women 'at risk', i.e. with stone-containing or removed gallbladder. The rates for men and women were approximately parallel, but with median 10% (range -4%-27%) higher in the women. In 1987 the corresponding rates at autopsies were 37% for women and 21% for men. As cholecystectomy rates are products of multiple variables which may be independent of the individual patient, such figures are a questionable measure of morbidity from gallstones, but so long as cholecystectomy rates rise, the need for treatment cannot have been met.