Cardiac MRI findings to differentiate athlete's heart from hypertrophic (HCM), arrhythmogenic right ventricular (ARVC) and dilated (DCM) cardiomyopathy.

To provide clinically relevant criteria for differentiation between the athlete's heart and similar appearing hypertrophic (HCM), dilated (DCM), and arrhythmogenic right-ventricular cardiomyopathy (ARVC) in MRI. 40 top-level athletes were prospectively examined with cardiac MR (CMR) in two university centres and compared to retrospectively recruited patients diagnosed with HCM (n = 14), ARVC (n = 18), and DCM (n = 48). Analysed MR imaging parameters in the whole study cohort included morphology, functional parameters and late gadolinium enhancement (LGE). Mean left-ventricular enddiastolic volume index (LVEDVI) was high in athletes (105 ml/m2) but significantly lower compared to DCM (132 ml/m2; p = 0.001). Mean LV ejection fraction (EF) was 61% in athletes, below normal in 7 (18%) athletes vs. EF 29% in DCM, below normal in 46 (96%) patients (p < 0.0001). Mean RV-EF was 54% in athletes vs. 60% in HCM, 46% in ARVC, and 41% in DCM (p < 0.0001). Mean interventricular myocardial thickness was 10 mm in athletes vs. 12 mm in HCM (p = 0.0005), 9 mm in ARVC, and 9 mm in DCM. LGE was present in 1 (5%) athlete, 8 (57%) HCM, 10 (56%) ARVC, and 21 (44%) DCM patients (p < 0.0001). Healthy athletes' hearts are characterized by both hypertrophy and dilation, low EF of both ventricles at rest, and increased interventricular septal thickness with a low prevalence of LGE. Differentiation of athlete's heart from other non-ischemic cardiomyopathies in MRI can be challenging due to a significant overlap of characteristics also seen in HCM, ARVC, and DCM.

Expression of anaphylatoxin receptors on platelets in patients with coronary heart disease.

OBJECTIVE: Inhibition of components of the complement system or of its receptors has been postulated as a concept for primary and secondary prevention in atherosclerosis and was applied in clinical trials. Although the anaphylatoxin-receptors C3aR and C5aR are commonly associated with inflammatory cells, in vitro studies suggested their expression also on platelets. METHODS AND RESULTS: Expression levels of C3aR and C5aR were measured by flow cytometry in a collective of 302 patients with documented coronary artery disease (CAD) including patients with stable CAD (n = 152), unstable angina (n = 54), acute myocardial infarction (AMI; Non-ST elevation myocardial infarction, n = 70, ST elevation MI, n = 26) or healthy controls (n = 21). Patients with stable CAD, unstable angina or AMI had significantly higher expression of C5aR on platelets in comparison to healthy controls (MFI 14.68 (5.2), 14.56 (5.18) and 13.34 (4.52) versus 10.68 (3.1)); p < 0.001). In contrast, the expression of C3aR on platelets was significantly enhanced in patients with stable and unstable CAD but not in patients with AMI compared to controls. While there was a strong correlation between the soluble ligands of these receptors C3a and C5a, we observed only a weak correlation with their receptors on platelets. Similarly, agonist induced aggregation (MEA, ADP, and TRAP) showed only a weak correlation with the expression level of anaphylatoxin - receptors on platelets. Of note, the expression of both anaphylatoxin-receptors on platelets strongly correlated with platelet activation as assessed with the surface activation marker P-selectin (r = 0.47, p > 0.001 for C3aR, r = 0.76 for C5aR, p < 0.001). Likewise, we observed a positive correlation of C3aR with other molecules associated with platelet activation such as SDF-1. CONCLUSION: In summary, we observed a positive correlation between the expression of anaphylatoxin-receptors C3aR and C5aR with platelet activation in patients with CAD. Further investigations are needed to study the clinical and mechanistic relevance of these findings.

Does the federal Family and Medical Leave Act of 1993 create a hole in ERISA preemption?

ERISA's board preemption provision has survived many challenges to its scope and effect. Now it may have succumbed in the face of a few statements tucked into the legislative history of the federal Family and Medical Leave Act (FMLA). Language in the legislative history presents the view that the Act was meant to overturn ERISA preemption of state family and medical leave laws. The text of the FMLA contains no corroborating language to support that view. However, at least one court found the statements in the legislative history to be persuasive and ruled that under the FMLA, ERISA does not preempt state family and medical leave laws that regulate ERISA plans. If other courts follow that decision, there will be great implications to employee benefit plan regulation and administration. This article explores the court's decision and the relationship between the FMLA and ERISA preemption.

Acquired loss of red cell Kell antigens.

A 19-year-old patient with a long history of idiopathic thrombocytopenic purpura developed a potent antibody against a high-incidence antigen in the Kell blood group system. The direct antiglobulin test on his red cells was negative. His cells exhibited profound depression of Kell blood group antigens, but antigens of other blood groups were normal. Transfusion of incompatible blood was well tolerated and differential agglutination tests, using selected Rh antisera, showed in vivo survival of the transfused red cells for more than 8 weeks. However, the transfused red cells also showed acquired loss of Kell antigens. Five months after the initial findings, Kell-related antibody disappeared and Kell antigens reappeared on his red cells. The patient's serum stored from the initial investigation now reacted with his freshly collected red cells. These data suggest that an environmental agent in the patient's plasma was responsible for the temporary loss of Kell antigens from red cells in his circulation.

Acquired loss of red-cell Wj antigen in a patient with Hodgkin's disease.

A patient with Hodgkin's disease became temporarily Wj-negative with alloanti-Wj in his serum. Four human autoantibodies, and 1 of 2 murine monoclonal antibodies, with serological characteristics of anti-Wj were nonreactive with his red cells, confirming that they have anti-Wj specificity. Six siblings of the patient are all Wj-positive. The patient was also temporarily Anton-negative, and cross-testing between Wj and Anton red cells and antisera showed mutual compatibility, indicating that the antigens are the same. The patient and 3 of his 6 siblings are also of the rare Lu: - 13 phenotype, providing the first evidence that this is an inherited characteristic.

Isolation of Kell-active protein from the red cell membrane.

Kell blood-group-active protein has been isolated by labeling red cell surface proteins with 125I, sensitizing intact cells with anti-K1, anti-K2, anti-K7, or anti-K22, solubilizing the cell membranes, isolating immune complexes, and separating their components by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Each antibody separated a protein of approximately 93,000 daltons. Periodic-acid Schiff (PAS) staining of Kell protein showed that it was glycosylated. When separated under non-reducing conditions, Kell protein had different SDS-PAGE characteristics with protein bands of approximately 85,000 daltons and 115,000 daltons. This suggests that in the red cell membrane Kell protein is complexed with other proteins. Quantitative experiments made with anti-K7, anti-K22, and a mixture of anti-K7 and anti-K22 indicate that both antigen specificities are present in the same molecule. These biochemical data support serological studies which indicate that K22 is part of the Kell system.

Positive direct antiglobulin tests at birth without demonstrable maternal antibody.

A healthy 38-year-old white woman had two abortions and three live children. Red cells from each of her living children at birth had a strongly positive direct antiglobulin test. Detailed studies on the third child showed that the cells were sensitized by IgG. Maternal serum, tested by a range of techniques against reagent red cells and the husband's cells, showed no unusual antibody. Maternal serum and eluates prepared from red cells of the third child did not react with fresh cells from the older siblings (aged 7 and 10 years). Follow-up on the third child showed that the direct antiglobulin test was positive at 2 months, weakly positive at 4 months, and negative at 8 months. Red cells collected at 8 months of age did not react with the stored eluate prepared from the baby's sensitized red cells at birth. The most likely explanation of these data is that the children inherited a paternal antigen that is only present as a red cell surface-active structure during fetal development.

An individual with McLeod syndrome and the Kell blood group antigen K(K1).

McLeod syndrome is an X-linked condition in which individuals of McLeod blood group phenotype have weak Kell antigens, acanthocytic red cells, and a muscular disorder. We now report a family in which two brothers have McLeod syndrome. One is K:-1, while the other is the first known K:1 person with McLeod syndrome. The K1 gene in the latter is expressed weakly and was inherited from the father, in whom it is expressed normally. The brothers have the same clinical and laboratory manifestations of McLeod syndrome but have different Kell genes. Therefore, the Kell gene is unlikely to have any positive input into development of McLeod syndrome; its role is one of passive involvement in which its expression is modified.

Autoimmunity and the Kell blood groups: auto-anti-Kpb in a Kp(a+b-) patient.

An example of auto-anti-Kpb in a Kp(a+b-) patient is described. The antibody present in the patient's serum and in eluates from her red cells was IgG. It did not bind complement, and did not cause in vivo hemolysis. 9 months after recognition of the autoimmune state the direct antiglobulin test had become negative and anti-Kpb was no longer detectable. It is postulated that autoimmunity involving the Kell blood group may be precipitated by antigens or enzymes of microbial origin.