Methodology of cultivating human tissue in diffusion chambers

The proliferative activity of human pulmonary carcinoma cells has been examined by autoradiography in 48 cultures in diffuse chambers, incubated with 3H thymidine under various conditions. 3H thymidine has been injected intraperitoneally to one group of animals, in another group the diffuse chambers have been removed from the animals and incubated in culture medium with 3H thymidine in the same concentration. The proliferation intensity of the cell cultures from the same patients has been virtually the same in both modes of incubation. This permits simplifying the autoradiography technique for such experiments, thus helping to avoid the difficulties connected with radioactive waste utilization.     

Surface acidic sites on supported titanium-magnesium catalyst for propylene polymerization: ESR study via adsorption of stable nitroxyl radicals

ESR was used for studying the interaction between the stable nitroxyl radical TEMPO (2,2,6,6-tetramethylpyperidin-1-oxyl) and the titanium-magnesium catalysts TiCl₄/MgCl₂ and TiCl₄/MgCl₂ · nD (D is either diisobutyl phthalate or 2,2-diisobutyl-1,3-dimethoxypropane), as well as TiCl₄/MgCl₂ · nD treated with triethylaluminium. In all cases, only part of the surface titanium complexes (18–53 mol-%) exhibit Lewis acid properties and can interact with TEMPO. The portion of titanium complexes with acidic properties depends on the composition and preparation of the catalysts, and it decreases upon treatment with triethylaluminium.     

Medium-term results of heart transplantation using donors over 63 years of age

BACKGROUND: The continual shortage of hearts for transplantation (HTx) led to the expansion of the donor pool by accepting older donors. We compared the medium-term follow-up of patients after HTx with older hearts (over the age of 63 years) with those of patients after HTx with younger hearts. PATIENTS AND METHODS: Since April 1994 we have used hearts for HTx from donors older than the age of 63 years. Until November 1998, 309 HTx and 9 re-HTx were performed in 309 adults with a mean age of 50.7+/-10.9 years (range 17-68 years). There were 252 men and 57 women. The patients were divided into two groups: group I--donor age under 63 years (296 patients, mean age 50.4+/-11 years; mean donor age 38.1+/-13 years; mean follow-up 1.7+/-1.6 years); group II-donor age of more than 63 years (13 patients, mean age 57.4+/-5.6 years; mean donor age 65.1+/-2.1; mean follow-up 2.2+/-1.6 years). There were no differences in the etiology of heart failure, gender, or ischemia time between the groups. The patients in group II were significantly older (P = 0.008). Multiple factors were analyzed in the groups, which included changes in the left/right ventricle ejection fraction, early postoperative mortality (up to 30 days), cumulative survival rates and cardiac-dependent morbidity [myocardial infarction, malignant arrhythmias, coronary stenosis (>50% in one of the main coronary arteries) and transplant vasculopathy]. Additionally, freedom from cytomegalovirus infection (rise of titer or seroconversion) and freedom of acute rejection episodes grade > or =2 (International Society of Heart & Lung Transplantation [ISHLT]) were analyzed. RESULTS: After 1 year mean left and right ventricle ejection fraction were good in both groups and did not significantly change for up to 2 years. No Re-HTx was performed in group II. The early postoperative mortality was similar in both groups (P = 0.8). Also, the cumulative survival rates were similar in both groups (P = 0.87). Long-term cardiac morbidity was lower in group I (P = 0.03). The long-term freedom from cytomegalovirus infection in group I was significantly higher when compared with group II (P = 0.0002). The long-term freedom from severe rejection episodes was similar in both groups (P = 0.3) CONCLUSION: The study found a significant increase in long-term cardiac morbidity due to more focal coronary stenosis in group II, and freedom from cytomegalovirus infection, but did not find significant differences in the long-term survival between patients who received hearts from donors of up to 63 years of age and from those more than 63 years. The acceptance of donors older than 63 years old for HTx does not worsen the outcome of the recipients. The careful selection of older donors, with close monitoring of the coronary situation after HTx and expanded indications for revascularization of older hearts, could make HTx with older hearts, even in older recipients, a safe option.     

The state of the pulmonary surfactant system in patients with the acute pulmonary damage syndrome

There were examined the surface-active properties and phospholipidious contents of the breathed out air condensate and the general respiratory compliance (C) in 21 patients with an acute pulmonary damage syndrome (APDS), caused by pancreonecrosis, peritonitis, polytrauma, sepsis. The lowering of the surface activity, reducing of phosphatidylcholine content and raising of phosphatidylethanolamine level, significant C lowering were noted. Such changes were more pronounced in patients, which have died subsequently. This testifies the profound inhibition of the pulmonary surfactant system activity in patients with APDS. It is expedient to apply the exogenic surfactant preparations for the treatment of patients with APDS.     

Biomedical Fiber-Optic Temperature and Pressure Sensors

The construction of biomedical fiber-optic temperature and pressure sensors is reviewed. The sensors can be used in surgery and oncology. High-technology products for biomedical applications of this class are discussed. Progress in fiber-optic technology has lead to the introduction of new fiber-optic sensors in the medical equipment industry. A catheter with a temperature sensor for an endoscope with 6.0-m operating channel is described.