Production of RBC autoantibody mimicking anti-D specificity following transfusion in a patient with weak D Type 15.

BACKGROUND: Weak D-type RBCs have fewer D epitopes, but it remains unclear whether individuals with certain types of weak D produce alloanti-D directed at D epitopes absent from the RBCs, and whether it is an alloantibody or an autoantibody. We report the first case of a patient with a weak D Type 15 who produced autoantibodies mimicking alloanti-D. CASE REPORT: A 52-year-old Japanese male with weak D developed anti-D 3 months after transfusion of D-negative and -positive RBCs, and the antibody persisted for 24 months with a consistently negative direct antiglobulin test. Eluates from the patient's RBCs demonstrated anti-D specificity. The recipient did not exhibit any signs of delayed hemolytic transfusion reaction. As his anti-D was removed by the different adsorbing cells of weak D Type 15 and autologous as well as D positive, D negative, weak D Type 24, and partial DVa, it was thought to be an autoantibody mimicking anti-D rather than an alloantibody. The patient's RBCs reacted weakly with the 13 anti-D reagents used in the study. Polymerase chain reaction and nucleotide sequencing revealed that the patient had an RHD genotype of RHD*01N.01/RHD*15. CONCLUSION: Anti-D, produced in a patient with weak D Type 15 after transfusion, was found to be mimicking autoanti-D. Alloanti-D was excluded by an adsorption study with different RBC types.

Effects of the brown rice diet on visceral obesity and endothelial function: the BRAVO study.

Brown rice (BR) and white rice (WR) produce different glycaemic responses and their consumption may affect the dietary management of obesity. In the present study, the effects of BR and WR on abdominal fat distribution, metabolic parameters and endothelial function were evaluated in subjects with the metabolic syndrome in a randomised cross-over fashion. In study 1, acute postprandial metabolic parameters and flow- and nitroglycerine-mediated dilation (FMD and NMD) of the brachial artery were determined in male volunteers with or without the metabolic syndrome after ingestion of either BR or WR. The increases in glucose and insulin AUC were lower after ingestion of BR than after ingestion of WR (P= 0·041 and P= 0·045, respectively). FMD values were decreased 60 min after ingestion of WR (P= 0·037 v. baseline), but the decrease was protected after ingestion of BR. In study 2, a separate cohort of male volunteers (n 27) with the metabolic syndrome was randomised into two groups with different BR and WR consumption patterns. The values of weight-based parameters were decreased after consumption of BR for 8 weeks, but returned to baseline values after a WR consumption period. Insulin resistance and total cholesterol and LDL-cholesterol levels were reduced after consumption of BR. In conclusion, consumption of BR may be beneficial, partly owing to the lowering of glycaemic response, and may protect postprandial endothelial function in subjects with the metabolic syndrome. Long-term beneficial effects of BR on metabolic parameters and endothelial function were also observed.