[Treatment-refractory anaemia in a 35-year-old heart transplant recipient on chronic hemodialysis]. / Therapierefraktäre Anämie bei einem 35-jährigen Dialysepatienten nach Herztransplantation.

This article presents a case of pure red cell aplasia in a 35-year-old heart transplant recipient on chronic hemodialysis. Elevated parvovirus B19 immunoglobulin M blood levels were detected along with a high viral load of 80 billion IU/ml quantified by polymerase chain reaction. Bone marrow examination revealed giant proerythroblasts confirming parvovirus B19 infection. High-dose intravenous immunoglobulin was used for treatment. Anaemia had significantly improved 4 weeks later. Parvovirus B19 infection should be excluded in organ transplant recipients with anaemia due to ineffective erythropoiesis.

Actin-microtubule interplay coordinates spindle assembly in human oocytes.

Mammalian oocytes assemble a bipolar acentriolar microtubule spindle to segregate chromosomes during asymmetric division. There is increasing evidence that actin in the spindle interior not only participates in spindle migration and positioning but also protects oocytes from chromosome segregation errors leading to aneuploidy. Here we show that actin is an integral component of the meiotic machinery that closely interacts with microtubules during all major events of human oocyte maturation from the time point of spindle assembly till polar body extrusion and metaphase arrest. With the aid of drugs selectively affecting cytoskeleton dynamics and transiently disturbing the integrity of the two cytoskeleton systems, we identify interdependent structural rearrangements indicative of a close communication between actin and microtubules as fundamental feature of human oocytes. Our data support a model of actin-microtubule interplay that is essential for bipolar spindle assembly and correct partitioning of the nuclear genome in human oocyte meiosis.