Reference intervals of red blood cell parameters and platelet count for healthy adults in Japan.

Although it is known that red blood cell (RBC) parameters and platelet count depend on ethnicity and sex, their reference intervals in healthy Asian populations are limited. The aim of this study was to establish reference intervals for RBC parameters and platelet count for healthy adults in Japan. A total of 750 healthy adults (447 women and 303 men; median age 40 years (18-67 years) at seven Japanese centers who participated in regular medical checkups entered this study. Their RBC parameters and platelet count were measured using automated hematocytometers. The reference intervals of the RBC parameters and platelet count according to sex in healthy adults were determined. There was an age-specific decrease in RBC counts and an age-specific increase in mean corpuscular volume in men. This study emphasizes the need to consider sex and age in the clinical use of reference intervals of RBC parameters.

Reference intervals of white blood cell parameters for healthy adults in japan.

INTRODUCTION: While white blood cell (WBC) parameters have been suggested to depend on ethnicity and gender, reference intervals in healthy Asian populations are limited. The present study established reference intervals of WBC parameters for healthy adults in Japan. METHODS: A total of 750 healthy adults (447 women and 303 men; 18-67 years old, median 40 years old) at 7 Japanese centers who participated in regular medical checkups entered this study. The WBC parameters were measured using automated hematocytometers and blood film reviews by a manual microscopic examination. RESULTS: The reference intervals of the WBC parameters according to gender in healthy adults were determined. Age-specific decreases in WBC counts of both gender groups and in neutrophil counts of women were noted. Favorable correlations between the hematocytometer and microscopic methods were found in neutrophils, lymphocytes, and eosinophils but not in monocytes or basophils. CONCLUSION: This study suggests the need to consider gender and age in the clinical use of reference intervals of WBC parameters.

Reduction in adverse reactions to platelets by the removal of plasma supernatant and resuspension in a new additive solution (M-sol).

BACKGROUND: Leukodepletion reduces but does not eliminate adverse reactions to platelet concentrate (PC). As an alternative strategy, plasma reduction or washing of platelets should be considered. However, the efficacy of this strategy is still unclear. STUDY DESIGN AND METHODS: A total of 12 patients who experienced adverse reactions at a 29 to 100 percent reaction rate for plasma-PC were enrolled. The reactions were allergic reactions and nonhemolytic transfusion reactions, such as chills. Plasma-removed PC (W/R-PC), which was suspended in a recently developed additive solution (M-sol) containing less than 20 mL plasma, was prepared. W/R-PCs in M-sol were then transfused into patients after an overnight storage period; the occurrence of adverse reactions was monitored and 1- and 24-hour corrected count increment (CCI) values were evaluated. RESULTS: Although plasma-PC caused reaction in 12 patients, W/R-PC prevented reactions in 11 of 12 patients, with 1 patient having one minor allergic reaction of 15 transfusions. There was a significant difference in the incidence of reaction (p < 0.0001, Fisher's exact test). On a per-transfusion basis, the reaction rate for W/R-PC (1/156, 0.64%; 95% confidence interval [CI], 0.02%-3.5%) was reduced significantly compared to that for plasma-PC (117/276, 42%; 95% CI, 36%-48%; p < 0.0001). W/R-PC gave findings of satisfactory CCI at 1 hour (22,400 +/- 8,000/microL) and 24 hours (15,400 +/- 8,000/microL). No clinically evident bleeding episodes were recorded. CONCLUSIONS: W/R-PC suspended in M-sol in the presence of less than 20 mL plasma can be transfused safely and eliminate a wide range of adverse reactions to plasma-PC.

[Sideroblastic anemia after prolonged linezolid therapy].

Linezolid is an effective and well-tolerated antibiotic for the treatment of infections caused by Gram-positive pathogens. Some reports have shown that linezolid treatment for more than 2 weeks has been associated with reversible bone marrow suppression, especially thrombocytopenia and anemia. We encountered a case of sideroblastic anemia following prolonged linezolid therapy in a laryngeal cancer patient. He received linezolid therapy for multiple abscesses due to MRSA. Before treatment, the Hb level was 12.5 g/dl and then slowly decreased to 5.9 g/dl for 2 months during treatment. Ringed sideroblasts were detected in the bone marrow. Linezolid was discontinued and the Hb level was slowly increased. This case was considered to reflect a rare complication of linezolid therapy.

Community-based suicide prevention through group activity for the elderly successfully reduced the high suicide rate for females.

The lack of social support is the most common risk factor for late-life suicide. Few previous community-based interventions against the lack of social relationships reduced suicide. This study aims to evaluate outcomes of a community-based prevention program against suicide amongst the elderly in rural Japan. During 1995-2002, the program based on population strategy including group activity, psychoeducation and self-assessment of depression but no screening for depression, was implemented for elderly residents in Yuri town, Japan (5-year average population 6817; 5-year average suicide rate [> or =65 years old] 291.4/10(5)). Changes in the relative risk of suicide for individuals (> or =65 years old) before and after the 8-year implementation were estimated by the incidence rate ratio (IRR), using a quasi-experimental design with a neighboring reference, Chokai town, Japan (5-year average population 8136; 5-year average suicide rate [> or =65 years old] 216.5/10(5)). The risk of elderly females in Yuri completing suicide was reduced by 76% (age-adjusted IRR, 0.24; 95% CI, 0.10-0.58), while there was no change in the risks for Yuri's elderly males and both Chokai's elderly males and females. General loglinear analysis estimated a ratio of the female IRR in Yuri to that in its Akita prefecture of 0.35 (95% CI, 0.14-0.84), showing that the reduction of the risk in the intervention area was greater than a historical trend. A community-based suicide prevention through a group intervention designed to increase knowledge and to cultivate social relationships would be effective for elderly females but not males.

Differential blocking action of dihydropyridine Ca2+ antagonists on a T-type Ca2+ channel (alpha1G) expressed in Xenopus oocytes.

Recent reports show that efonidipine, a dihydropyridine Ca2+ antagonist, has blocking action on T-type Ca2+ channels, which may produce favorable actions on cardiovascular systems. However, the effects of other dihydropyridine Ca2+ antagonists on T-type Ca2+ channels have not been investigated yet. Therefore, in this study, we examined the effects of dihydropyridine compounds clinically used for treatment of hypertension on a T-type Ca2+ channel subtype, alpha1G, expressed in Xenopus oocytes. These effects were compared with those on T-type Ca2+ channel. Rabbit L-type (alpha1Calpha2/deltabeta1a) or rat T-type (alpha1G) Ca2+ channel was expressed in Xenopus oocytes by injection of cRNA for each subunit. The Ba currents through expressed channels were measured by conventional 2-microelectrode voltage-clamp methods. Twelve DHPs (amlodipine, barnidipine, benidipine, cilnidipine, efonidipine, felodipine, manidipine, nicardipine, nifedipine, nilvadipine, nimodipine, nitrendipine) and mibefradil were tested. Cilnidipine, felodipine, nifedipine, nilvadipine, minodipine, and nitrendipine had little effect on the T-type channel. The blocks by drugs at 10 microM were less than 10% at a holding potential of -100 mV. The remaining 6 drugs had blocking action on the T-type channel comparable to that on the L-type channel. The blocking actions were also comparable to that by mibefradil. These results show that many dihydropyridine Ca2+ antagonists have blocking action on the alpha1G channel subtype. The action of dihydropyridine Ca2+ antagonists in clinical treatment should be evaluated on the basis of subtype selectivity.

Identification of R(-)-isomer of efonidipine as a selective blocker of T-type Ca2+ channels.

Efonidipine, a derivative of dihydropyridine Ca(2+) antagonist, is known to block both L- and T-type Ca(2+) channels. It remains to be clarified, however, whether efonidipine affects other voltage-dependent Ca(2+) channel subtypes such as N-, P/Q- and R-types, and whether the optical isomers of efonidipine have different selectivities in blocking these Ca(2+) channels, including L- and T-types. To address these issues, the effects of efonidipine and its R(-)- and S(+)-isomers on these Ca(2+) channel subtypes were examined electrophysiologically in the expression systems using Xenopus oocytes and baby hamster kidney cells (BHK tk-ts13). Efonidipine, a mixture of R(-)- and S(+)-isomers, exerted blocking actions on L- and T-types, but no effects on N-, P/Q- and R-type Ca(2+) channels. The selective blocking actions on L- and T-type channels were reproduced by the S(+)-efonidipine isomer. By contrast, the R(-)-efonidipine isomer preferentially blocked T-type channels. The blocking actions of efonidipine and its enantiomers were dependent on holding potentials. These findings indicate that the R(-)-isomer of efonidipine is a specific blocker of the T-type Ca(2+) channel.