Antibody-mediated glycophorin C coligation on K562 cells induces phosphatidylserine exposure and cell death in an atypical apoptotic process.

BACKGROUND: Glycophorin C (GPC) is necessary in the maintenance of red blood cell structure. Severe autoimmune hemolytic anemia and hemolytic disease of the fetus and newborn (HDFN) have been associated with Gerbich (Ge) blood group system antigens expressed on GPC. Previous in vitro studies with cord blood progenitor cells have shown that anti-Ge suppresses erythropoiesis. STUDY DESIGN AND METHODS: Here, we evaluated the K562 erythroleukemic cell line to study the cellular effects of a murine anti-GPC. Cell proliferation was evaluated after treatment with anti-GPC. Flow cytometry was used to evaluate exofacial phosphatidylserine (PS) expression and cell viability (propidium iodide binding). Cell morphology was evaluated under light microscopy with cytospin preparations stained with May-Grünwald Giemsa. RESULTS: Anti-GPC dramatically inhibited K562 proliferation and increased PS expression, consistent with cytoplasmic blebbing, suggesting evidence of apoptosis. Z-VAD-FMK, an inhibitor of classical apoptosis, was unable to reverse the suppressive effect of anti-GPC. However, hemin was able to attenuate growth suppression. CONCLUSION: Together, the data suggest that anti-GPC suppresses erythroid proliferation through the induction of nonclassical apoptosis.

Predictive blood group genetics in hemolytic disease of the fetus and newborn: a 10-year review of a laboratory evaluation of amniotic fluid-derived DNA.

OBJECTIVE: To identify the types of requests, the patterns of testing, and the error rates associated with the genetic identification of fetuses at risk for immune-mediated hemolytic disease. METHOD: Retrospective review of the laboratory information system for all fetal blood group genotyping tests performed at Mount Sinai Hospital, Toronto, Canada from January 1997 to December 2006. RESULTS: Amniotic fluid-derived DNA, from 220 women (243 pregnancies), was tested for one or more antigens (279 tests) when the father was heterozygous for the inferred blood group antigen or was unavailable. The PCR amplification failure rate of amniotic fluid-derived DNA was 5.0%. When the father was considered hemizygous for RHD or was not available, the fetus was positive in 68.6% and 72.7% of cases, respectively. Two amniotic fluid-derived DNA KEL1 SSP-PCR results did not correlate with the result determined from cultured amniocyte DNA. CONCLUSIONS: Paternal RHD hemizygosity may be overestimated. Thus, we recommend that RHD zygosity be established by molecular analysis of the RHD breakpoint. Cultured amniocytes should be reserved for testing if the amniotic fluid-derived DNA is inconclusive due to PCR amplification failure. We use PCR-RFLP genotyping methods for RHCE*E/RHCE*e (Rh E/e), KEL1/KEL2 (K/k), FYA/FYB (Fy(a/b)), and JKA/JKB (Jk(a/b)).

Lymphangiogenesis following obstruction of large postnodal lymphatics in sheep.

We examined the impact of lymph flow obstruction in large post-nodal lymphatic vessels in sheep. A silk ligature was placed 2 cm downstream from the prescapular or popliteal lymph node and tightened to interrupt flow. At 6, 12 and 16 weeks after lymph flow blockage, a network of small interconnecting lymphatics (approximately 10-40 microm in diameter) could be observed in the vicinity of the ligature. These were identified using antibodies to the lymphatic endothelial markers LYVE-1 or VEGFR-3 or unequivocally, with the upstream intraluminal injection of the non-specific cell dye CFDA-SE. The observed lymphangiogenesis coincided with increased levels of Prox1, Tie2 (Y992) phosphorylation, MAPK activation, and decreased Akt activition. In the popliteal preparations, saline was infused into the prenodal ducts upstream of the regeneration site. The slopes of the inflow pressure versus flow relationships were 17.3+/-3.6, immediately after vessel obstruction, 36.2+/-9.6 at 6 weeks and 15.0+/-5.3 at 12-16 weeks. For comparison, the average slope in a completely intact popliteal system was 3.1+/-0.3 (from a previous publication). The resistance to flow remained high up to 12-16 weeks after flow obstruction suggesting that normal flow parameters had not been achieved over this time. The lymph node appeared to have some role in limiting the impact of post-nodal lymph obstruction, a function that appeared to be compromised by lymph stasis.

Delirium in the postoperative cardiac patient: a review.

UNLABELLED: BACKGROUND AND AIM OF REVIEW: Cardiac surgery is increasingly common and relatively safe, but there are frequent reports of neuropsychiatric sequelae occurring in the postoperative period. One of the most common neuropsychiatric presentations of cardiac surgery is delirium, also called postcardiotomy delirium (PCD). Despite the vast numbers of cardiac surgeries performed today, there is a paucity of data on risk factors and management options of PCD available to the clinician. This review aims to summarize available information, increase clinicians' awareness of PCD and suggest effective management of this illness. METHODS: Our literature search was completed using the databases Medline and CINAHL; it was limited to human and English language studies from 1964 to the present. Search terms included "delirium," "agitation," "postoperative," "cardiac," "neuropsychiatric," "neuroleptics," "psychosis," "surgery," "treatment," "postcardiotomy," and "pharmacotherapy." RESULTS: Our review of the literature revealed several risk factors for PCD, as well as various options for its pharmacological management. CONCLUSIONS: A multifactorial model should be applied when considering risk stratification for and prevention of delirium postoperatively. Pharmacologically, conventional antipsychotic agents, such as haloperidol, have long been used to manage delirium. In light of haloperidol's side effects, particularly those applicable to the cardiac patient, further research is required into the role of second generation antipsychotics. These agents are common in clinical use, and may be the preferred medications.

Treatment of agitation following traumatic brain injury: a review of the literature.

Agitation, restlessness, and aggression are frequent neurobehavioural sequelae in the early stages of recovery from traumatic brain injury (TBI). These behavioural symptoms disrupt patient care and impede rehabilitation efforts. We review the current literature (1985 onwards) examining the pharmacological management of post-TBI agitation in both acute and post-acute conditions. This article will assess the evidence for the use of selected alkylphenols, benzodiazepines, estrogens, antiandrogens, neuroleptics/antipsychotics, antidepressants, anti-Parkinsonian agents, antipsychotics, anticonvulsants, lithium carbonate, buspirone, beta-blockers, and psychostimulants in agitated TBI survivors. Review of the literature suggests that there is limited evidence to accurately guide clinicians in the management of this patient population.