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Background Thrombotic thrombocytopenic purpura (TTP) is a rare but serious complication in pregnancy that places the mother and fetus at high risk for morbidity and mortality. This case illustrates novel pregnancy complications associated with this rare medical condition. Case presentation A 31-year-old G3P0020 at 28 weeks and 1 day was admitted with severe thrombocytopenia and was ultimately diagnosed with TTP. With therapeutic plasma exchange (TPE), maternal status improved. At 28 weeks 6 days, however, non-reassuring fetal testing prompted cesarean delivery with placental abruption noted intraoperatively. Pathology examination confirmed placental abruption and also revealed multiple placental infarcts. Conclusion While medical management of TTP can significantly improve the health of the mother, this case highlights the potential role of TTP in abruption and other placental pathology and thus, the need for close fetal surveillance throughout an affected pregnancy.

Tungsten accumulates in bone but is neither labile nor inert once absorbed. Tungsten’s relatively high cytosolic solubility and availability are problematic given its association with childhood lymphocytic leukemia. In light of tungsten’s technological prevalence, and the increased concern of regulatory agencies, here we characterize the chemical form and localization in mice exposed to tungsten through drinking water. Using X-ray fluorescence spectroscopy, we report accumulation of tungsten in bone tissue with some sites having ~10-fold greater intensities than background levels. The long bone tissue studied includes cortical, cancellous and bone marrow. Persistence of tungsten in cortical bone tissue following removal of the source indicates that it is retained in an insoluble form. The X-ray absorption near-edge structure spectra for tungsten in these tissues indicate that it is no longer in the originally administered form, orthotungstate, but rather resembles the heteropolytungsate species, phosphotungstate. Tungstate accumulates in bone and can be resistant to chelation therapies typically used to remove heavy metals in vivo. Here, tungstate is shown to accumulate in mouse bone tissue in a persistent, insoluble form proposed to be condensed polytungstate.

Under influence of hematopoietic growth factors, particularly thrombopoietin (TPO), hematopoietic stem cells in the bone marrow go through a process of commitment, proliferation, differentiation, and maturation and become mature megakaryocytes. At this critical point, terminally differentiated megakaryocytes face a new fate: ending the old life as mature megakaryocytes by induction of apoptosis and beginning a new life as platelets by fragmentation of the large megakaryocyte cytoplasm. These events are as important as megakaryocyte commitment, proliferation, differentiation, and maturation, but the molecular mechanisms regulating these events are not well established. Although TPO drives megakaryocyte proliferation and differentiation and protects hematopoietic progenitor cells from death, it does not appear to promote platelet release from terminally differentiated megakaryocytes. Although mature megakaryocyte apoptosis is temporally associated with platelet formation, premature megakaryocyte death directly causes thrombocytopenia in cancer therapy and in diseases such as mvelodysplastic syndromes and human immunodeficiency virus infection. Also, genetic studies have shown that accumulation of megakaryocytes in bone marrow is not necessarily sufficient to produce platelets. All of these findings suggest that platelet release from megakaryocytes is an important and regulated aspect of platelet production, in which megakaryocyte apoptosis may also play a role. This review summarizes recent research progress on megakaryocyte apoptosis and platelet release.

Darbepoetin alfa is a novel erythropoiesis stimulating protein (NESP), which stimulates erythropoiesis by the same mechanism as recombinant human erythropoietin (rHuEPO). NESP has been shown to be safe and efficacious in patients with chronic renal failure. NESP is biochemically distinct from rHuEPO, due to its increased sialic acid content. NESP has an approximately 3-fold greater half-life. rHuEPO has been shown to be safe and effective for the treatment of chemotherapy-induced anaemia. This study assessed the safety and efficacy of NESP administered once per week, under the supervision of a physician, to patients with solid tumours who were receiving multicycle chemotherapy for up to 12 weeks. Three dose cohorts are presented in this sequential, unblinded and dose-escalating study. Thirteen to 59 patients received NESP (0.5, 1.5 or 2.25 mcg kg−1wk−1) in each cohort. Patients were monitored for adverse events, including antibody formation to NESP and for effects on haemoglobin. NESP appeared to be well tolerated. Adverse events were similar across all cohorts and were consistent with the population being studied. No antibody formation was detected over the 16-week study period and follow-up. A dose–response relationship was evident for NESP and multiple measures of efficacy, including proportion of patients responding to NESP and the mean change in haemoglobin by week 4 and end of treatment for NESP 0.5, 1.5 and 2.25 mcg kg−1wk−1cohorts (mean change in haemoglobin at end of treatment was 1.24, 1.73 and 2.15 g dl−1respectively). Controlled studies of this agent at higher doses and less frequent schedules of administration are ongoing. © 2001 Cance Cancer Research Campaign