A cross-sectional analysis of the effects of various centrifugation speeds and inclusion of the buffy coat in platelet-rich plasma preparation.

INTRODUCTION: Platelet-rich plasma is an autologous blood preparation which is used in various medical specialties because of its regenerative properties. There is a wide variation in platelet-rich plasma preparation protocols and attaining the ideal platelet yield (>1 million platelets/µL) in a clinic setting can be challenging. We aimed at analyzing the centrifuge spin rates at which to attain an ideal platelet-rich plasma yield and also to study the effect of inclusion of the buffy coat after the first spin on the final platelet concentration in platelet-rich plasma. METHODS: Seventy-five whole blood samples were obtained and divided into two groups - (1) leukocyte-rich platelet-rich plasma group and (2) leukocyte-poor platelet-rich plasma group. Samples in both groups were centrifuged using the dual spin method, at one of three centrifugation speed combinations (initial "soft" spin and second "hard" spin speeds, respectively): (1) 100 g/400 g, (2) 350 g/1350 g and (3) 900 g/1800 g. Platelet, red blood cell (RBC) and white blood cell (WBC) counts in both groups were compared. RESULTS: The 100 g/400 g spin gave a high platelet yield (increase of 395.4 ± 111.1%) in the leukocyte-poor-platelet-rich plasma group, while in the leukocyte-rich platelet-rich plasma group both 100 g/400 g and 350 g/1350 g spins resulted in significantly higher yields with an increase of 691.5 ± 316.3% and 738.6 ± 193.3%, respectively. LIMITATIONS: The study was limited by a smaller sample size in the pure platelet-rich plasma (leukocyte-poor platelet-rich plasma) group. CONCLUSION: Ideal platelet yields can be achieved with both the 100 g/400 g as well as the 350 g/1350 g spins using the buffy coat inclusion method while the 100 g/400 g spin for "pure" platelet-rich plasma accomplishes a near-ideal platelet count with significantly reduced contamination with other cells.

[Chronobiological aspects of the action of diaminodiphenylsulfone on hematological mice induces in summer and winter seasons ]. / Khronobiologicheskie aspekty vliianiia diaminodifenilsul'fona na gematologicheskie pokazateli u myshei v letnii i zimnii sezony goda.

Mice experiments were made to study effects of diaminodiphenylsulphone (DDS)--basic antileprous drug--on circadian rhythms of hemoglobin levels, counts of red cells and leukocytes. The time of the drug administration varied within the day while seasons of the year were two--winter and summer. Blood components were studied with unified methods. The results of the study showed that DDS has significant effects on the structure of circadian rhythms of the above blood components. These effects correlate with the season of the year and time of DDS administration.

Investigations into the haemolytic effects of dapsone therapy in leprosy patients.

Investigations into the haemolytic effects of dapsone therapy were carried out in forty four leprosy patients admitted to the Sacred Heart Leprosy Centre, Kumbakonam. They received weight based dapsone dosages varying from 1.3-3.3 mg/kg body weight. Blood levels and urinary Dapsone/creatinine ratio were assessed at 1 day, 7 days and 30 days of Dapsone treatment. At the same points of time, haematological observations were also carried out. Serum bilirubin as well as blood mathaemoglobin were also examined. The findings showed a reduction in Hb levels at 30 days observation in a good proportion of cases on 100 mg. In one case (child) weighing 15 kg and receiving 50 mg dapsone increased mathaemoglobin was observed. It is suggested that dapsone dosage be regulated to body weight and preferably not to exceed 1.5 mg/kg body weight.

Vitamin E and dapsone-induced hemolysis.

Sixteen patients, each receiving 100 mg of dapsone per day, were studied for evidence of hemolysis. Vitamin E (dl-alpha tocopherol acetate), 800 mg/day, was then administered for up to three months, and dapsone therapy was continued at the same dose. Hemolysis factors were reexamined immediately prior to cessation of vitamin E therapy. No substantial change was demonstrable for levels of hemoglobin, reticulocyte count, and haptoglobin at the end of vitamin E therapy, despite a significant rise in serum vitamin E levels. Erythrocyte survival measured in four patients before and at the end of vitamin E therapy also showed no substantial change. Erythrocyte Heinz body count, however, fell in nine of 15 patients studied, and none showed an increase in this measurement while receiving vitamin E. We conclude that in patients receiving dapsone at 100 mg/day, vitamin E therapy at 800 mg/day does not substantially ameliorate the hemolytic effect of this drug.