The leftward deletion alpha-thal-2 haplotype in a black subject with hemoglobin SS

We have identified a black individual with homozygous sickle cell anemia who is the silent carrier of alpha-thalassemia (genotype - alpha/alpha alpha) due to heterozygosity for the leftward deletion alpha-thal-2 haplotype. This deletion has not been described previously in a black subject and is the only leftward deletion that we have found among 255 alpha-thal-2 chromosomes from sickle cell subjects. Its effects on the clinical, hematologic, biosynthetic, and cellular pathology of sickle cell anemia resemble those reported for the common alpha-thalassemia genotypes of the black population.     

Negative charge distribution and density on the surface of oxygenated normal and sickle red cells

Negative charges on the external surface of red cells were visualized by colloidal iron hydroxide labelling of 50% of the membrane area after osmotic hemolysis and glutaraldehyde fixation. Counts were made over randomly selected areas on electron micrographs at 350,000 x magnification. Statistical analyses showed that at the 95% level of confidence there was no significant difference between oxygenated normal (AA) and sickle (SS) cells in either the distribution or the density of negative charges.     

MR imaging of the scrotum: normal anatomy

High-resolution magnetic resonance (MR) imaging with a surface coil was utilized to evaluate the normal scrotum. Scrotal contents, spermatic canal, and inguinal regions were visualized within the same field of view. Differences in signal intensity in the testis, epididymis, tunica albuginea, fluid, fat, and spermatic cord allowed for clear delineation of these structures in detail. The high contrast and spatial resolution of MR imaging, coupled with the wide field of view and absence of ionizing radiation, make MR imaging well suited for evaluation of the scrotum.     

Parental beliefs associated with the use of child restraint devices

Despite the passage of laws mandating the use of child restraintdevices (CRDs), children remain at risk of injury and deathfrom car crashes. This risk could be substantially reduced ifparents complied with laws concerning CRDs. In this study ahierarchical model consisting of five different types of beliefsconcerning CRD use is developed and tested by means of a telephonesurvey of 140 parents in North Carolina. Tested are parents'beliefs concerning: (i) the consequences of having their childride in a CRD; (ii) the safety of alternatives to CRD use forchild passengers; (iii) the likelihood of their child's beingin a crash; (iv) the probability of injuries of varying severityassociated with potential crashes; and (v) the role of attributionsin mediating the effects of previous crash experiences. ParentalCRD use was significantly associated with the first and secondtypes of beliefs in the model. Implications of the study forthe design of programs promoting CRD use are discussed.     

Quantitation of CD62, soluble CD62, and lysosome-associated membrane proteins 1 and 2 for evaluation of the quality of stored platelet concentrates

BACKGROUND: Platelets become activated during storage, which results in secretion of granules, vesiculation of microparticles, secretion of protein, and a number of other biochemical and morphologic processes that decrease the utility of platelet concentrates stored for transfusion. STUDY DESIGN AND METHODS: To evaluate the quality of stored platelet concentrates, the cell surface expression of specific activation-dependent antigens (CD62 and lysosome-associated membrane proteins 1 and 2 [LAMP-1, LAMP-2]) on platelets stored in a hospital blood bank over a 7-day period was examined. Relative microparticle counts and the expression of CD62 by microparticles, as well as platelet concentrate supernatant levels of soluble CD62, were determined. RESULTS: The percentage of platelets expressing CD62 increased significantly from Day 1 to Day 5 (p < 0.05) of storage; the mean fluorescence values for CD62 did not. In contrast, the mean fluorescence values of LAMP-1 and LAMP-2 rose significantly (p < 0.01 and p < 0.05, respectively) between Days 1 and 5. Significant declines in CD62, LAMP-1, and LAMP-2 percent expression and mean fluorescence were seen on Day 6 of storage (p < 0.001). Microparticle numbers increased significantly during storage and correlated with levels of CD62 protein (free and membrane-bound) (r = 0.95 vs. Day 2, p < 0.05; r = 0.88 vs. Day 5, p < 0.05). CONCLUSION: Flow cytometric evaluations of the expression of cell surface CD62, LAMP-1, and LAMP-2 are complementary tests that, especially when used in conjunction with the quantitation of CD62 protein, provided a simple and effective means of evaluating the quality of platelet concentrates stored for transfusion.