Lymphokine abnormalities in aplastic anemia: implications for the mechanism of action of antithymocyte globulin

Anti-thymocyte globulin (ATG) provides effective therapy for many patients with aplastic anemia, and its mechanism of action has been presumed to be secondary to lymphocytotoxicity. However, our studies of lymphocyte function in aplastic anemia show marked abnormalities of lymphokine production, which ATG may modulate. In 12 of 17 patients with aplastic anemia, interleukin 2 (IL2) production was markedly elevated in vitro (P less than .01 by paired statistical analysis). Expression of the IL2 receptor, or Tac antigen, on peripheral lymphocytes assessed by flow microfluorometry was also increased above the normal range in 11 of 15 cases. Studies of ATG suggested that it might act to stimulate lymphocyte function. In vitro, ATG is a mitogen, as measured by incorporation of 3H-thymidine into blood mononuclear cells; the response of cells to ATG from patients with aplastic anemia was exaggerated in comparison with normals. Cell proliferation was accompanied by production of IL2 to levels that were, in some cases, similar to those obtained with lectin stimulation. Finally, supernatants from lymphocytes cultured in the presence of ATG were able to replace adherent cells in providing growth factors for the support of nonadherent cells in methylcellulose hematopoietic colony assays. These results provide a mechanism for an "immunostimulatory" action of ATG in effecting hematopoietic response in some patients with aplastic anemia.     

Human thrombopoietin levels are high when thrombocytopenia is due to megakaryocyte deficiency and low when due to increased platelet destruction

Thrombopoietin (TPO), the ligand for c-mpl, stimulates proliferation of committed megakaryocytic progenitors and induces maturation of megakaryocytes. To better understand factors regulating TPO levels, we measured blood levels of TPO in patients with impaired platelet production due to aplastic anemia (AA) and with platelet destructive disorders, including idiopathic thrombocytopenic purpura (ITP), posttransfusion purpura (PTP), drug purpura (DP), and X-linked thrombocytopenia (XLTP). The TPO receptor capture enzyme immunoassay (EIA) used had a detection limit of integral of approximately-150 to 200 pg/mL. TPO was undetectable in 88 of 89 normal individuals. Eighteen of 19 patients with AA and a mean platelet count (MPC) of 18,000/microliters (2,000 to 61,000/microliters) had markedly elevated TPO levels (mean, 1,467 pg/mL; range, 597 to 3,834 pg/mL). Eight AA patients who responded to immunosuppressive therapy with their MPC increasing to 140,000/microliters (92,000 to 175,000/microliters) had substantial decreases in TPO (mean, 440 pg/mL; range, 193 to 771 pg/mL). Initial TPO levels did not differ significantly between responders and nonresponders. In contrast, all 21 patients with ITP and an MPC of 16,000/microliters (1,000 to 51,000 /microliters) had undetectable TPO levels, as did 6 patients with acute PTP or DP and 2 patients with XLTP. Megakaryocyte mass, reflected in the rate of platelet production, appears to be the major determinant of TPO levels in thrombocytopenic patients rather than circulating platelet levels per se. Measurement of serum TPO may be useful in differentiating thrombocytopenias due to peripheral destruction from those due to thrombopoietic failure.     

REPAIR OF ABDOMINAL AORTIC ANEURYSM AFTER RENAL TRANSPLANTATION WITHOUT RENAL PROTECTION

SUMMARY The successful resection is reported of an abdominal aortic aneurysm after renal transplantation without the use of bypass or cooling procedure to preserve the kidney.     

JunB as a potential mediator of PTHrP actions: new gene targets Ephrin B1 and VCAM‐1

Parathyroid hormone‐related protein (PTHrP) is an integral mediator of physiologic and pathologic processes and has demonstrated actions in the periodontium. PTHrP functions via AP‐1, and specifically through JunB. This study identified JunB‐dependent downstream mediators of PTHrP using OCCM cementoblastic transfectants with JunB over‐ or reduced expression. Over‐expressing cells showed an increase in proliferation, while the opposite was seen in siRNA transfected cells. Microarray analysis of over‐expressing cells revealed more than 1000 regulated genes. Three genes were investigated in more detail. The PTH/PTHrP receptor (PTHR1) and ephrin B1 (EfnB1) were down‐regulated, and vascular cell adhesion molecule‐1 (VCAM‐1) was up‐regulated with JunB over‐expression. JunB siRNA transfectants had increased PTHR1, but reduced ephrin B1 and unaltered VCAM‐1 in vitro. To validate these targets, parental OCCM cells and primary osteoblasts were treated with PTHrP, resulting in reduced PTHR1 and ephrin B1, and increased VCAM‐1. Cell transfectants were implanted subcutaneously in vivo, and microarray analysis and RT‐PCR performed. Over‐expression of JunB down‐regulated PTHR1 and ephrin B1, and increased VCAM‐1. JunB siRNA transfectant implants had increased PTHR1 and ephrin B1, but no altered VCAM‐1. These data highlight new gene targets for PTHrP and indicate JunB is a critical mediator of PTHrP actions.     

The rising rate of admissions for tonsillitis and neck space abscesses in England, 1991–2011

Introduction

Sore throats and tonsillitis represent a considerable health burden as well as a significant source of expenditure for the National Health Service (NHS). As part of the recent NHS savings drive, the introduction of ‘procedures of low clinical effectiveness’ (PoLCE) lists has reinforced a large reduction in the number of tonsillectomies performed. We carried out a cross-sectional study of trends in emergency sore throat admissions in the context of the number of tonsillectomies performed.

Methods

Hospital Episode Statistics (HES) data were extracted. Office for National Statistics data were also used.

Results

Between 1991 and 2011, the overall tonsillectomy rate fell by 44%. In the same time, the admission rate for tonsillitis rose by 310% (Pearson’s r=–0.67, p=0.01). The peritonsillar abscess admission rate rose by 31% (r=–0.79, p<0.01). Between 1996 and 2011, the overall tonsillectomy rate fell by 41% and the retro and parapharyngeal abscess admission rate rose by 39% (r=–0.55, p=0.026). There was a 14% overall increase in tonsillectomy and sore throat associated bed days. This was despite the large fall in tonsillectomy numbers and the reduction in length of hospital stay.

Conclusions

Efforts to reduce the tonsillectomy rate are correlated with a significant rise in emergency admissions. The rise in the retro and parapharyngeal abscess rate is perhaps most alarming given the very high mortality of these conditions. Bed day data suggest that no net saving has been made despite the new measures.     

Fall prediction using decision tree analysis in acute care units

[Purpose] To present an accurate and straight-forward system of fall prediction by performing decision tree analysis using both the fall assessment sheet and Berg balance scale (BBS). [Participants and Methods] The participants in this retrospective study were inpatients from acute care units. We extracted the risk factors for falls from the fall assessment and performed a decision tree analysis using the extracted fall risk factors and BBS score. [Results] “History of more than one fall in the last 1 year”, “Muscle weakness”, “Use of a walking aid or wheelchair”, “Requires assistance for transfer”, “Use of Narcotics”, “Dangerous behavior”, and “High degree of self-reliance” were fall risk factors. The decision tree analysis extracted five fall risk factors, with an area under the curve of 0.7919. Patients with no history of falls and who did not require assistance for transfer or those with a BBS score ≥51 did not fall. [Conclusion] Decision tree-based fall prediction was useful and straightforward and revealed that patients with no history of falling and those who did not require assistance for transfer or had a BBS score ≥51 had a low risk of falling.Key words: Falling, Balance, Decision tree