The nervous system function of patients with periodontitis

Analysis of the function of the nervous system, based on clinical, neurological, and psychological studies in 78 patients with generalized periodontitis, revealed central regulation disorders without signs of organic lesions of the brain in 76% patients. The authors claim that stress and a high level of personal anxiety may be responsible for the development of these disorders, which was confirmed by the results of psychological testing.     

The role of cytoplasmic [Ca2+] in glucose-induced inhibition of respiration and oxidative phosphorylation in Ehrlich ascites tumour cells: a novel mechanism of the Crabtree effect

The effect of Ca2+ on energy-coupling parameters of Ehrlich ascites carcinoma was studied in digitonin-permeabilized cells. In nominally Ca-free medium the permeabilized cells respond to the addition of ADP by increased oxygen uptake with externally added respiratory substrates (succinate or pyruvate), decrease of the mitochondrial membrane potential (delta psi) and alkalinization of the medium. This typical behaviour is drastically changed if Ca2+ is added. The subsequent addition of ADP induces neither State 3 respiration, nor decrease of delta psi, nor alkalinization of the medium, indicating a complete block of ATP synthesis. These effects are produced by both a single pulse of 100 microM Ca2+ and a preincubation for 2 min with 0.4-1.0 microM Ca2+. Preincubation of the cells with glucose or deoxyglucose prior to permeabilization makes them sensitive to Ca2+ concentrations as low as 0.3 microM. In view of the previous finding that glucose and deoxyglucose produce an increase of cytoplasmic [Ca2+] in Ehrlich ascites cells [Teplova VV. Bogucka K. Czyz A. Evtodienko YuV. Duszyński J. Wojtczak L. (1993) Biochem. Biophys. Res. Commun., 196, 1148-1154; Czyz A. Teplova VV. Sabala P. Czarny M. Evtodienko YuV. Wojtczak L. (1993) Acta Biochim. Polon., 40, 539-544], the present results suggest that cytoplasmic Ca2+ plays a crucial role in the Crabtree effect.     

Effects of granisetron with doxorubicin or epirubicin on ECG intervals

Commercially available serotonin-type 3 (5-HT3) receptor antagonists (ondansetron, granisetron, and tropisetron) have shown no clinically significant adverse effects on the cardiovascular system. In the dose-ranging evaluation of dolasetron, computer-generated ECGs revealed clinically asymptomatic prolongations of ECG intervals. We performed a clinical trial in which the possible changes in ECG intervals following a single 3-mg i.v. injection of granisetron and an injection of either doxorubicin or epirubicin were registered using computerized ECG analysis in cancer patients. A total of 30 patients who were designated to receive 3 mg granisetron i.v. for the prophylaxis of emesis induced by doxorubicin or epirubicin were entered into the study. Computer-generated ECG tracings were obtained before treatment, following the injection of 3mg granisetron, and immediately after doxorubicin or epirubicin injection. The mean PR interval duration increased from 160 to 166 ms after granisetron infusion (P=0.02). Doxorubicin and epirubicin did not potentiate this change. There was no statistically significant change in cardiac rhythm, QRS duration, or QTc intervals. The observed minor changes in the PR time following i.v. injection of granisetron do not seem to be of clinical relevance.