Detection of drug-induced apoptosis by flow cytometry after alkaline extraction of ethanol fixed cells

A new flow cytometric method was developed to detect apoptotic cells with fragmented DNA and to determine cell cycle distribution of viable cells, in the same sample, by propidium iodide staining. Apoptosis, in HT58 human B lymphoma cells, was induced by etoposide and/or by staurosporine. Using appropriate alkaline solutions (between 1-10 mN NaOH in 150 mM saline) followed by neutralization with buffer solution, the fragmented DNA can be extracted quantitatively from ethanol fixed cells. Further, good resolution of the cell cycle distribution can be obtained in unimpaired cells without RNase treatment. Furthermore, unlike the widely used hypotonic-detergent extraction of unfixed cells, the suggested extraction method can prevent drug-induced disintegration of dead cells when karyorrhexis occurs. This work was supported by Hungarian National Research Foundation (OTKA I/352 and OTKA II/2622).     

Does the service at a large oncologic out-patient clinic satisfy the patients' perceived need?

Describes the physical status and quality of life in ambulatory oncologic patients seen at the Norwegian Radium Hospital (NRH) and assesses their satisfaction with the out-patient service. During a two-week period in 1993 517 consecutive patients completed a qualify-of-life questionnaire (EORTC QLQ-C30) during their out-patient visit at the NRH. The results of the EORTC QLQ-C30 were compared with those from a similar study performed in 1991 (211 patients evaluated during one week).     

Chronic treatment with epidermal growth factor stimulates growth of the urinary tract in the rat

Twenty-four male Wistar rats, 8 weeks old, were allocated into three groups and treated with human recombinant epidermal growth factor (EGF) administered subcutancously in doses of 0, 30, and 150 g/kg per day for 4 weeks. Blood sampling was done every 2nd week and urine sampling was done for 2 consecutive days every week. The most striking finding was that the ureters were dose dependently enlarged, due to growth of all layers of the ureteric wall. The urothelium of the bladder showed considerable hyperplasticity with a widening of the basal proliferative compartment and a normal differentiation pattern as observed by the expression of carbohydrate epitopes, characterized with lectinohistochemistry. Blood examination revealed a decrease in blood haemoglobin concentration and a slight increase in serum creatinine concentration in the high-dose group. There were no effects of EGF on the urinary excretion of electrolytes, proteins, and endogenous EGF.     

Pulmonary gas exchange capacity is reduced during normovolaemic haemodilution in healthy human subjects

Purpose

To test the hypothesis that a physiological compensatory mechanism maintains respiratory gas exchange during normovolaemic haemodilution.

Methods

Pulmonary gas exchange capacity was evaluated in seven healthy subjects by measuring the lung diffusion of carbon monoxide (DLCO). During the measurement, various breath-holding times, inspiratory volumes, and sitting or supine positions, were randomly selected in an attempt to alter pulmonary capillary perfusion. KCO was calculated as the percentage of theoretical values of the ratio of DLCO by alveolar volume and normalized by sex, age, and height. Normovolaemic haemodilution (NH) was performed by bleeding an average blood volume of 1 L with simultaneous Dextran 60 replacement to obtain an haematocrit below 35%.

Results

After NH, haemoblogin concentration [Hb] decreased from 14.94 ± 0.96 to 12.5 ± 0.98 g · dl^?1 (P < 0.001). KCO decreased (P < 0.02) but remained closely correlated to [Hb] at every lung volume (< 0.02). Breathholding time and body position had no effect.

Conclusion

Moderate NH impairs pulmonary gas exchange capacity in awake, resting healthy subjects. There is no evidence of any compensatory mechanism since the KCO vs [Hb] relationship is unchanged.     

Hypothermia and the 5-HT syndrome induced by CGS 12066B independently of 5-HT(1B) receptor activation

The effects of CGS 12066B (3-14mg/kg), a putative 5-HT(1B) agonist, on 5-HT behavioral syndrome, motor activity and body temperature, were investigated in rats. The animals were well adapted to the experimental conditions before testing, and data sampling started at the same hour for each rat. The highest dose of CGS 12066B clearly reduced body temperature and induced flat body posture and hindlimb abduction. No significant change was seen in motor activity. The CGS 12066B-induced changes were not antagonized by 5-HT(1B) receptor antagonists, or antagonists at other 5-HT receptor. In fact, the 5-HT(1A) antagonist NAN-190 and especially the non-selective 5-HT antagonist methiothepin, with definite 5-HT(1B) receptor blocking properties, both potentiated the decrease in body temperature. The findings suggest that the behavioral and body temperature effects of CGS 12066B are not easily explained by 5-HT(1B) receptor stimulation, but may be mediated by activation of non-serotonergic mechanisms. Similar conclusions in studies with other 5-HT(1B) agonists suggest a common problem with such drugs.     

Chagasic heart disease in Mexico. 1st case diagnosed by positive xenodiagnosis

We describe the first case of chronic Chagas heart disease in México, in whom the illness was corroborated by means of the "xenodiagnosis". The patient had changing bundle branch block and also A-V block that required insertion of a pacemaker. This disease is seldom seen in Mexico.     

Pharmacokinetics and oral bioavailability of pyridostigmine in man

Summary The pharmacokinetics of pyridostigmine was evaluated after intravenous injection in two healthy male volunteers and after oral administration to five subjects. Plasma concentrations of pyridostigmine were determined after ion pair extraction from plasma and analysis by gas chromatography — mass spectrometry with chemical ionization, using d₆-pyridostigmine as internal standard. Degradation of pyridostigmine in vitro was compensated for by use of the deuterated internal standard and by rapid cooling and separation of plasma after blood sampling. After intravenous administration of pyridostigmine 2.5 mg the plasma elimination half-life was 1.52 h, the volume of distribution was 1.43 l/kg and the plasma clearance 0.65 l/kg × h. The pharmacokinetic constants were very similar after oral administration of pyridostigmine 120 mg; the elimination half-life was 1.78±0.24 h, the volume of distribution 1.64±0.29 l/kg and the plasma clearance was 0.66±0.22 l/kg × h. The bioavailability was calculated to be 7.6±2.4%. When pyridostigmine was taken together with food, the time to reach the peak plasma concentration was prolonged from 1.7 to 3.2 h. Bioavailability, however, was not influenced by concomitant food intake. Steady-state plasma concentrations of pyridostigmine were measured in myasthenic patients on their ordinary dose schedule of cholinesterase inhibitor drugs. More than a seven-fold difference in steady-state plasma concentration was found between patients taking approximately the same daily dose of pyridostigmine.     

Clinical pharmacology of pyridostigmine and neostigmine in patients with myasthenia gravis.

Determination of plasma concentration of pyridostigmine in 20 myasthenic patients on maintenance therapy revealed rather small intraindividual variations within a dose interval. The predose concentration varied considerably between different patients and up to seven fold in patients on the same daily dose. No pharmacokinetic interaction between pyridostigmine and neostigmine was found in five patients studied. In six patients the decrement in the deltoid muscle was studied in parallel with determination of the plasma concentrations following administration of pyridostigmine or neostigmine. In these patients the existence of a "bell-shaped" dose response curve is suggested with the maximal effect at a concentration of 30-60 ng/ml for pyridostigmine and 5-15 ng/ml for neostigmine.     

Experimental regional myocardial ischaemia and myocardial uptake of potassium analogues; Intercomparison of 42K, 86Rb and 201Tl

The uptake of ⁴²K, ⁸⁶Rb and ²⁰¹Tl by non-ischaemic and ischaemic myocardium was determined in rats with coronary artery ligature lasting 10, 30, 60 and 120 min, and in control rats without ischaemia. Whereas the myocardial concentration of ²⁰¹Tl and ⁴²K in control rats was similar and higher than that of ⁸⁶Rb, ²⁰¹Tl was superior to the other two radionuclides due to its significantly higher accumulation in non-ischaemic myocardium and the higher ratio of non-ischaemic to ischaemic radioactivity.The ⁸⁶Rb accumulation in non-ischaemic myocardium and non-ischaemic/ischaemic ratio began to decrease from its maximum at 10 min. ²⁰¹Tl, ⁴²K and ⁸⁶Rb blood levels in intact animals decreased rapidly after intravenous injection to low and nearly stabilized values at 5 min.Na⁺K⁺-ATPase activity in the ischeamic myocardium was high in the acutely ischaemic myocardium and decreased to below control levels after 4 h of ischaemia; changes in activity could not influence the low uptake of potassium analogues in fresh ischaemic myocardium.     

Food intake, eating-related complaints, and smell and taste sensations in patients with cancer of the lung, ovary and breast undergoing chemotherapy

Nutritional status and energy and protein intake were studied in 52 patients with cancer of the breast, ovary or lung before, after 1, and after 3 cycles of aggressive chemotherapy. Pre-treatment intakes were somewhat lower than recommended and did not change after 3 cycles of chemotherapy, neither did nutritional status. Many patients had eating-related complaints, but these complaints did not increase significantly with chemotherapeutic treatment. In 31 patients electrical taste detection thresholds and chemical smell detection thresholds were measured before and after 3 cycles of chemotherapy. Changes in thresholds had no relation to changes in energy and protein intake. Perceived taste and smell changes were not reflected in chemosensory threshold values.