Serum cholinesterase activity and proteosynthetic function of liver in patients with diabetes mellitus.

INTRODUCTION: Diabetes mellitus is associated with a lot of changes in intermediary metabolism and several authors reported on higher frequency of liver diseases in patients with diabetes. AIM OF THE STUDY: Was to establish the changes of blood serum cholinesterase, prealbumin and albumin, parameters which are accepted as an index of liver proteosynthetic function, in patients with diabetes mellitus. PATIENTS AND METHODS: The study group consisted of 207 patients with diabetes mellitus (83 patients with type I and 124 patients with type II diabetes mellitus). Control group consisted of 179 healthy subjects. The activity of cholinesterase was assayed by the kinetic method, concentrations of prealbumin and albumin were determined immunochemically. RESULTS: Activity of serum cholinesterase was significantly higher in group of patients with diabetes mellitus than in control group (65.05 vs 73.33 microkat/l). The concentration of prealbumin was lower in blood serum of patients with diabetes than in controls (308.10 vs 285.85 mg/l). Serum levels of albumin were not different in both studied groups. After dividing of patients according to the type of diabetes, 80 % of abnormal values of cholinesterase and prealbumin were present in patients with type II diabetes. CONCLUSIONS: The results of our study showed abnormal values of determined liver tests approximately in 22 % of patients with diabetes mellitus. The character of laboratory changes--increased activity of cholinesterase, decreased concentration of prealbumin and normal levels of albumin, suggests development of liver steatosis in these patients. The most of pathological findings were in patients with diabetes type II (Tab. 3, Ref. 20).

Recent efforts in artificial heart research in Czechoslovakia.

The authors present basic information about the technical development of the total artificial heart (TAH) and TAH drivers. Long-term experiments, in which the TAH TNS-Brno-II and VII and the Rostock hearts were implanted, are described. Long-term experiments were dedicated to analysis of specific pathophysiologic problems (venous hypertension, thrombogenesis, and calcification) in order to increase survival rates. Thrombogenesis has been partially solved in the TNS-BRNO-VII device by optimal TAH construction using an asymmetric driving diaphragm, the undulating motion of which produced excellent results. Two methods for prevention of increase in central venous pressure (CVP) are verified: administration of antihypertensive drugs and atrial electrical stimulation. Of 155 calves studied, 50 long-term experiments in calves and one in a goat were done. The survival of these animals extended from 31 to 293 days of pumping (average survival, 116.9 days). To prevent driving diaphragm calcification, we have incorporated exogenic inhibitors of calcification into the diaphragm biomaterial (polyurethane). A unique long-term experiment with intrathoracic TAH implantation in the goat is also described. In addition clinical use of the TAH as a bridge to transplantation is discussed. Parallel research with the left ventricular assist device (LVAD) system was studied experimentally, and twice used in patients. The TAH TNS-BRNO-VII/80/clin/ was used in four patients. It worked faultlessly for 22 hours to 10 days. More precise and specific indications for TAH implantation when used as a bridge to transplantation are needed.

Control and driving of pneumatic total artificial hearts TNS-BRNO-II and -III in long-term experiments.

Hemodynamic analysis was carried out during long-term experiments with the pneumatic total artificial hearts TNS-BRNO-II and TNS-BRNO-III to determine standard methods of starting artificial hearts and criteria for their long-term operation in vivo. In long-term experiments, regulatory mechanisms automatically regulating the systole length and diastolic aspiration pressure have also been verified. Comparison of hemodynamic variables obtained from invasive measurements with pneumatic pressure curves permitted the control and monitoring of the experiment in its entirety by noninvasive methods only. The control of the artificial heart using the Chirasist TN 3 and Chirasist TN 4 was adapted to specific properties of the pumps, above all to the functions of the atypical inlet valves. The terminal stages of the experiments have shown that a 100-ml pump can ensure survival of experimental calves up to 210 kg body weight.

A comparative study of a group of eight calves, surviving longer than 1 month with the total artificial heart.

Over the last 2 1/2 years, eight calves with implanted total artificial hearts (from experimental group IV) have survived for greater than 1 month. In this group two subgroups were further differentiated, subgroup IVa, including three calves surviving 31, 35, and 75 days, and subgroup IVb, with five calves surviving 104, 142, 150, and 155 days and one calf still surviving greater than 160 days. Mean survival in the fourth group was greater than 106.5 days. The artificial ventricles used were the TNS-BRNO-II made of polymethylmethacrylate (seven calves) and the TNS-BRNO-III, made of segmented polyetherurethane (one calf). The controller and driving units were of our own design. The Chirasist-TN-3 and TN-4 worked without trouble over the total duration of the studies in all calves. Autoregulation of suction was used in three of these calves. All calves survived in good physiological condition; however, some common changes were observed in all of them, such as a gradual central venous pressure increase and liver enlargement. Anticoagulation therapy was used in all calves. Causes of death were technical in three cases and biological in four. Body weight gains were normal in the majority of these calves, with slight individual differences observed. Diaphragm mineralization of various degrees was observed in three cases. In one of them it was directly related to the cause of death. These results are very encouraging for further development of the total artificial heart research in our center.