A dispermic chimerism detected in a Taiwanese potential unrelated hematopoietic stem cell donor.

Chimerism is defined as the presence of 2 or more than 1 genetically distinct cell populations in an organism. Dispermic chimeras are derived from the fertilization of 1 or 2 matured nuclei by 2 sperms. We here report detection of a healthy and phenotypically normal female with normal ABO red blood cell typing in whom dispermic chimerism was suspected after 3 alleles were identified at multiple human leukocyte antigen (HLA) loci using molecular HLA analysis. Molecular HLA typing showed the donor to have 3 HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1 alleles in blood, saliva and nail samples. In addition, 3 of her 9 short tandem repeat loci also showed to have 3 distinct alleles in blood, nail and saliva specimens. In all investigations, the third alleles were attributed to a dual paternal contribution. This case represents a dispermic chimerism, with 2 paternal and 1 maternal haplotypes variably distributed throughout body tissues in a healthy and phenotypically normal female without abnormalities in erythrocyte ABO blood group. The origin of this chimerism is probably due to the fertilization of a single egg and its polar body, or a parthenogenetic egg, by 2 sperms.

Trace elements burden in geriatric hemodialysis patients: a prospective multicenter collaborative study.

INTRODUCTION: Hemodialysis therapy and the aging process have been reported to interfere with the trace element (TE) status in the body. This multicenter collaborative study on blood levels of TE in geriatric hemodialysis (HD) patients was carried out with an aim to clarify the impact of the aging process and HD therapy on the TE status in such patients. METHODS: One hundred and fifty-one HD patients (65 male, 86 female), all aged over 60 (68.2+/-3.86 y), and 112 elderly controls (58 male, 54 female) with a mean age of 67.5+/-3.03 were enrolled. All patients underwent standard HD for at least 6 months. The artificial kidneys used were hollow-fiber dialyzers of cellulose membranes. Water used for HD was prepared by reverse osmosis. Blood was collected in the morning prior to dialysis and after fasting. Atomic absorption spectrophotometry was applied to measure blood levels of Pb, Cd and Hg as well as plasma levels of Cu, Zn and Al. Data are presented as mean +/- SEM. Student's t-test and linear regression were applied for statistics. RESULTS: Our geriatric chronic HD patients showed a marked elevation of blood Al and decreased plasma Zn concentrations. The blood levels of Cu, Cd, Pb and Hg were within normal limits. The blood concentrations of Al, Cu and Pb were significantly higher in HD patients than in the normal elderly controls, whereas Cd and Hg were similar in both groups, and Zn were lower in HD patients. Plasma Zn value decreased as dialysis duration increased, however there was a reversely linear correlation between plasma Zn and age. CONCLUSIONS: This data reported can be regarded as a starting point and may serve as an insight to further studies on TE imbalances in geriatric and chronic HD populations.

Structure and mechanical properties of selected biological materials.

Mineralized biological tissues offer insight into how nature has evolved these components to optimize multifunctional purposes. These mineral constituents are weak by themselves, but interact with the organic matrix to produce materials with unexpected mechanical properties. The hierarchical structure of these materials is at the crux of this enhancement. Microstructural features such as organized, layered organic/inorganic structures and the presence of porous and fibrous elements are common in many biological components. The organic and inorganic portions interact at the molecular and micro-levels synergistically to enhance the mechanical function. In this paper, we report on recent progress on studies of the abalone and Araguaia river clam shells, arthropod exoskeletons, antlers, tusks, teeth and bird beaks.

Cardiac manifestations of fatal enterovirus infection during the 1998 outbreak in Taiwan.

BACKGROUND: An outbreak of hand-foot-and-mouth disease caused by enterovirus infection occurred in Taiwan in 1998 and more than 70 infants and children with fulminant courses died. We compared the cardiac manifestations of fatal cases with patients who survived the enterovirus infection. METHODS: A total 187 patients with enterovirus infection were treated at Taichung Veterans General Hospital between April and June 1998. Enterovirus infection was diagnosed by history, clinical features, polymerase chain reaction study and/or viral culture. Cardiac examinations including complete physical examinations, electrocardiography and echocardiography were performed on seven cases (group I) with or without central nervous system (CNS) involvement, 30 patients with CNS involvement (group II), and 150 patients without CNS involvement (group III). RESULTS: There were no significant differences in sex distribution, days of fever, heart rate, systemic blood pressure or time from the onset of symptoms to hospital admission among the three groups. All group I patients had features of acute congestive heart failure, pulmonary edema and neurologic signs except one who presented with right-sided heart failure and neurologic signs. The echocardiographic findings of group I were a lower fractional shortening, lower ejection fraction, and more severe and higher incidence of mitral regurgitation (p < 0.01) than in groups II and III, but there were no significant differences in end-systolic wall stress, left ventricular end-diastolic internal dimension and incidence of pericardial effusion among the three groups. CONCLUSIONS: We conclude that seven infants and children (group I) died due to either severe cardiomyopathy or encephalopathy. The possible pathogenesis of enterovirus infection leading to death is reviewed and analyzed.