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A bi-enzymatic biosensor for monitoring of dihydroxyacetone production during oxidation of glycerol by bacterial cells of Gluconobacter oxydans is presented. Galactose oxidase oxidizes dihydroxyacetone efficiently producing hydrogen peroxide, which reacts with co-immobilized peroxidase and ferrocene pre-adsorbed on graphite electrode. This mediator-based bi-enzymatic biosensor possesses very high sensitivity (4.7 µA/mM in phosphate buffer), low detection limit (0.8 µM, signal/noise = 3), short response time (22 s, 95% of steady-state) and broad linear range (0.002-0.55 mM in phosphate buffer). The effect of pH, temperature, type of buffer, as well as different stabilizers (combinations of a polyelectrolyte and a polyol) on the sensor performance were carefully optimized and discussed. Dihydroxyacetone produced during a batch conversion of glycerol by the pectate-immobilized bacteria in an air-lift reactor was determined by the biosensor and by reference spectrophotometric method. Both methods were compared and were in a very good correlation. The main advantage of the biosensor is a very short time needed for sample analysis (less than 1 min).

The authors evaluated using clinical and echocardiographic examination the effect of chemotherapy involving bolus administration of doxorubicin on the heart muscle in 90 patients with non-Hodgkin lymphoma and with Hodgkin lymphoma. In 18% of patients they found an asymptomatic decrease of the left ventricular ejection fraction during chemotherapy, chronic cardiotoxicity was recorded in 5% patients, in 2% of the patients one year after termination of chemotherapy a clinically latent myocardial infarction was found. The diastolic function was impaired (impaired relaxation) in 44% patients after terminated chemotherapy and in 50% after one year. Echocardiographic examination provided evidence that the impaired systolic and diastolic function persists even after one year following termination of chemotherapy. High-dose chemotherapy with administration of peripheral stem cells did not lead to marked deterioration of left ventricular function as compared with patients who did not undergo this treatment. The main clinical complications--death, cardiotoxicity, relapse of the malignant disease, cardiovascular complications--were present in the course of a 18.5-month follow up after establishment of the diagnosis in 32% of the patients.

In the literature various regimes are described for successful collection of haematopoietic stem cells in patients with multiple myeloma. Most frequently cyclophosphamide is used, 5 g/m2 combined with different doses of haematopoietic growth factors. In our group the yields and tolerance of three stimulating regimes are compared: 1. cyclophosphamide 5 g/m2 and filgrastim (G-CSF) 5 micrograms/kg 2. cyclophosphamide 5 mg/m2 and filgrastim 10 micrograms/kg 3. cyclophosphamide 5 g/m2 and figrastim 5 micrograms/kg along with erythropoitin 50 IU/kg. Cyclophsphamide is administered always on the first day and the haematopoietic growth factors then from the third day till the end of collection of haematopoitic cells. In patients with multiple myeloma where only four cycles of VAD chemotherapy preceded and where radiotherapy of the axial skeleton was not used, optimal collection of haematopoietic stem cells was achieved after administration of cyclohosphamide 5 g/m2 with subsequent administration of 5 micrograms/kg G-CSF. By increasing the dose of G-CSF to 10 micrograms/kg or adding 50 IU/kg erthropoietin did not lead to a significant improvement of the tolerance and yield of this procedure.

The authors evaluated a group of 48 patients with relapsing or resistant Hodgkin's disease. The patients were treated by life-saving chemotherapy followed by large doses of chemotherapy and autologous transplantation of haematopoietic cells. For life-saving chemotherapy they used most frequently a combination of VIM in 40 patients and combinations of DHAP, MINE, MiniDexaBEAM. In 11 patients they changed the regime of life-saving chemotherapy because of a poor response. After completed life-saving chemotherapy 18 (37.5%) patients were in CR, 27 (56.2%) in PR and in 3 (6.3%) the disease progressed. For large dose chemotherapy the authors used BEAM in 32 patients, CBV in 2, Busulfan with Cyclophosphamide in 13 patients and Busulfan with Melfalan in one patient. After completion of large dose chemotherapy and subsequent autologous transplantation of bone marrow 31 (64.6%) patients were in CR, 8 (16.7%) in PR and the disease progressed in 9 (18.7%). In August 1999 a total of 44.9% patients in CR survive, the median period of follow up after autologous transplantation was 23 months. Life-saving chemotherapy with subsequent large dose chemotherapy led in the investigated group to induction of CR in 64.6% patients which is the basic prerequisite of long-term survival.

The authors investigated by echocardiography changes of left ventricular function in 79 patients with non-Hodgkin lymphoma or Hodgkin's disease who were treated by chemotherapy containing doxorubicin. In 22% patients they diagnosed during treatment a significant gradual decline of the left ventricular ejection fraction (change > 10% or a drop of EF below 50%) after a cumulative dose of 185 +/- 52 mg/m2 doxorubicin (median 200 mg/m2). Changes of the ejection fraction were at the expense of an increasing endsystolic left ventricular volume. These changes correlated closely with the increase of endsystolic stress of the left ventricular wall (r = -0.87). After administration of a cumulative doxorubicin dose of 100 mg/m2 a significant deterioration of indicators of diastolic filling of the left ventricle occurred--of the isovolumic relaxation period (IRP) and deceleration time (DT). The contribution of these early changes of diastolic function of the left ventricle for assessment of the risk of development of systolic dysfunction is not unequivocal. Prolongation of IRP > 12% as compared with the baseline value and at the same time above 95 ms had a 50% sensitivity, 50% specificity, a 26% positive prediction value a 74% negative prediction value and 50% diagnostic accuracy, change of DT > 13%, and at the same time prolongation above 200 ms had a 47% sensitivity 55% specificity, a 22% positive prediction value, a 78% negative prediction value and a 53% diagnostic accuracy. The authors found a significant relationship between the assessed changes of left ventricular function and clinical and haemodynamic indicators. Only the patients' age correlated significantly with IRP and DT values. Changes of the left ventricular ejection fraction were not associated with clinical signs of cardiac failure, they did not call for cardiological intervention and did not affect the course of chemotherapy. Contrary to some statements in the literature, the authors did not consider the described functional changes as sufficient to justify interference with chemotherapy. On the other hand, their importance for the development of late sequelae of chemotherapy with anthracyclines in adult patients must be based on long-term prospective follow-up.

Background: Autologous peripheral blood stem cell transplantation (APBSCT) is gradually replacing autologous bone marrow transplantation in many clinical settings. The key question is how to evaluate the quality of grafts. We analyzed the relationship between hematopoietic reconstitution and characteristics of patients and grafts., Methods and Results: Data from 95 APBSCTs were analyzed. Peripheral stem cells were obtained after mobilization using anti-neoplastic chemotherapy followed by Neupogen (G-CSF). After high dose chemotherapy and APBSCT, patients received Leucomax (GM-CSF). Patients were reinfused with a median of 6.1 x 10(6) (range 0.83-29.3) CD34+ cells/kg, and 25.1 x 10(4) (range 1.0-167.0) CFU-GM/kg of body weight. The median time to engraftment was 12 days (both for granulocytes 1 x 10(9)/l and platelets 50 x 10(9)/l). We found a significant correlation between the number of CD34+ cells and CFU-GM reinfused and also between their respective graft sizes and time to leukocytes, platelets, and granulocytes recovery. We did not find a significant correlation between the number of mononuclear cells reinfused and any analyzed parameter (time to engraftment, age, diagnosis, number of previous chemotherapies, type of mobilization or high-dose regimen). However, administration of preparative high-dose chemotherapy consisted of busulphan and cyclophosphamide was associated with the risk of a transient secondary graft failure., Conclusions: We conclude that the content of progenitors in PBSC grafts and time to booth leukocyte and platelet recovery are best estimated by the number of CD34+ cells (not less than 1 x 10(6)/kg) and CFU-GM (not less than 1 x 10(4)/kg). The number of mononuclear cells in an autologous PBSC graft is not suitable and useful for prediction of engraftment rate. There is probably no additional benefit of reinfusion of more than 8-10 x 10(6) CD34+ cells/kg and/or 50 x 10(4) CFU-GM/kg, because hematopoietic recovery is not more rapid.

Background: In patients with haematological malignities infectious complications take a very rapid course, and in particular during the period of neutropenia, they are not necessarily manifested by a clear symptomatology. Frequently they may be manifested only by an elevated temperature and general deterioration of the condition. The onset of shock then can be rapid and surprising. The objective of the work was to identify clinical and laboratory signs warning against the possible development of septic shock., Methods and Results: The investigation comprised a total of 38 patients hospitalised due to infectious complications at the intensive care unit because of general deterioration of the condition. 18 developed septic shock (group S), the remaining 20 (group N) achieved during hospitalisation at the ICU a stabilised condition. In both groups the laboratory values and clinical condition were followed up for 2-3 days prior to deterioration of the condition. Risk factors for development of septic shock in the group of investigated patients were: unusual weakness, heart rate above 95/min. beyond the temperature peak, hypoalbuminaemia, mucositis, hypokalaemia, presence of a central venous catheter and administration of parenteral nutrition.

Background: Treatment of Hodgkin's disease (HD) and non-Hodgkin lymphomas (NHL) is still unsatisfactory in patients resistant to primary therapy or those with early relapses. The objective of the trial was to test whether salvage regimens based on a combination of iphosphamide and etopozide have a sufficient anti-lymphoma effect, while the toxicity is still acceptable, and in conjunction with growth factors as satisfactory mobilizing potential for the collection of peripheral stem cells (PBSC)., Methods and Results: A group of 40 patients with relapsing and/or primary therapy resisting lymphomas (14 NHL, 26 HD) were treated by life saving or stimulating chemotherapy VIM (etopozide, iphosphamide, methotrexate) and MINE (iphosphamide mitoxanthrone, etopozide; mostly NHL). If the response to these regimes was inadequate, to some patients in addition mini (dexa) regimes were administered, BEAM and DHAP resp., with the objective to achieve maximum reduction of the tumourous mass before high-dosage treatment with the support of autologous PBSC. The authors administered 119 cycles of salvage chemotherapy (51 VIM, 46 MINE, 22 mini-dexa-BEAM and DHAP). The toxicity of chemotherapy and the therapeutic response were evaluated according to WHO criteria. The toxicity of VIM and MINE, with the exception for mobilization of desirable transient leukopenia, was not serious. During stimulation of PBSC on average three leukophereses were made and on average 9.9. 10(6) CD34+ cells/kg body weight of the patient were obtained and 53.2. 10(4) CFU-GM/kg (VIM), and 13.5. 10(6) CD34+ cells/kg 53.4. 10(4) CFU-GM/kg (MINE) resp. A total of 64% (MINE) and 61% (VIM) therapeutic responses were obtained, 14% (MINE) and 26% (VIM) complete remissions and 50% (MINE) and 35% (VIM) partial remissions., Conclusions: Life saving regimes, VIM and MINE, have a good antilymphoma activity, low toxicity and in combination with growth factors (filgrastim) they ensure a good collection of PBSC. As compared with other regimens, in particular for stimulation, VIM and MINE appear to be better.

Seventy-two Czech plum pox virus (PPV) isolates from different hosts were tested by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). In addition, the coat protein mobility and the RsaI restriction fragment length polymorphism (RFLP) pattern of reverse transcription-polymerase chain reaction-(RT-PCR) amplified coat protein (CP) gene fragment of the isolates were analysed. Both PPV-D and PPV-M serotypes were found in the Czech Republic. The results obtained by these different methods were in accord with exception of a few cases probably caused by mutation or recombination.

A follow-up study of persons with pleural plaques was concluded in 1984. The first cohort was made up of employees and retired workers with direct absestos exposure in an asbestos factory (AZ factory) producing heat-resistant textiles, friction engine parts and heat-resistant boards. The raw material was imported chrysotile and small amounts of crocidolite. The follow-up was started in the 1950s. Our second cohort comprised residents selected by radiographic screening in a vast area surrounding the AZ factory who had had indirect asbestos exposure by airborn asbestos fibres. The follow-up period began in the 1970s. A control group consisted of employees and retired workers of a railway repair shop, without exposure to asbestos dust and within a corresponding age bracket. At the time of assessing our results, most of the subjects assigned to all the three groups were no longer alive so we were able to analyse data regarding their life and death. Hyalinosis complicata and pleural mesothelioma (peritoneal mesothelioma in one case) were present and resulted in death only in those with direct asbestos exposure. While lung cancer was among the causes of death in both cohorts with exposure as well as in the control group, its prevalence in the group with direct exposure was significantly higher than in the control group. By contrast, "other neoplasia" was found both in the control group and in exposed persons without any specific prevalence.

Sixty patients with silicosis were examined by right heart catheterization and lung function tests during 1958-1966. In the 12-20 years follow-up the information was received of 57 patients (95%). 38 patients died (66.6%), 26 of them of the sequelae of silicosis. The death rate and the length of survival are related to mean pulmonary artery pressure, pressure gradient across pulmonary vascular bed, pulmonary vascular bed, pulmonary vascular resistance (PVR), arterial oxygen saturation (SaO2), vital capacity (VC) and forced expiratory volume (FEV). 12-year mortality in patients with pulmonary hypertension at rest was 81.3%, in contrast to 40.2% in the other patients. No patient with PVR higher than 2.55 u. survived. No patients with SaO2 lower than 89% survived 10 years. Patients with VC higher than 4000 ml at the initial examination are still living. By the method of discriminating analysis 2 main factors determining the prognosis were identified: pulmonary artery pressure and FEV 1".