Hemopathologic consequences of protracted gamma irradiation: alterations in granulocyte reserves and granutocyte mobilization

Aplastic anemia and myelogenous leukemia are prominent pathologic effects in beagles exposed to continuous, daily, low-dose gamma irradiation. In the present work, granulocyte reserves and related mobilization functions have been sequentially assessed by the endotoxin stress assay during the preclinical and clinical phases of these hemopoietic disorders. Characteristic patterns of granulocyte reserve mobilization are described that reflect given stages of pathologic progression. For radiation-induced leukemia, a five stage pattern has been proposed. In contrast, a simple pattern of progressive, time- dependent contraction of granulocyte reserves and mobilization capacity was noted in the development of terminal aplastic anemia. Early preclinical phases of radiation-induced leukemia appear to involve an extensive depletion of the granulocyte reserves ((phase I) during the first approximately 200 days of exposure followed by a partial renewal of the reserves and associated mobilization functions approximately 200 and 400 days (phase II). Sustained, subnormal granulocyte mobilizations (phase III) following endotoxin stress typify the responses of dogs during the intermediate phase, whereas late preclinical, preleukemic stages (phase IV) are characterized by a further expansion of the reserves and in the mobilization capacities, particularly of the less mature granulocytes. Such late alterations in the pattern of granulocyte mobilization, together with other noted cellular aberrancies in the peripheral blood and marrow, appear to indicate leukemia (phase V) onset.     

Lower limb vasodilatory capacity is not reduced in patients with moderate COPD

We compared exercise capacity (peak O₂ uptake; V̇O_2peak) and lower limb vasodilatory capacity in 9 patients with moderate COPD (FEV₁ 52.7 ± 7.6% predicted) and 9 age-matched healthy control subjects. V̇O_2peak was measured via open circuit spirometry during incremental cycling. Calf blood flow (CBF) measurements were obtained at rest and after 5 minutes of ischemia using venous occlusion plethysmography. While V̇O_2peak was significantly lower in the COPD patients (15.8 ± 3.5 mL·kg⁻¹·min⁻¹) compared with the control group (25.2 ± 3.5 mL·kg⁻¹·min⁻¹), there were no significant differences between groups in peak CBF or peak calf conductance measured 7 seconds post-ischemia. V̇O_2peak was significantly correlated with peak CBF and peak conductance in the control group, whereas no significant relationship was found between these variables in the COPD group. However, the rate of decay in blood flow following ischemia was significantly slower (p < 0.05) for the COPD group (−0.036 ± 0.005 mL·100 mL⁻¹·min⁻¹·s⁻¹) when compared with controls (−0.048 ± 0.015 mL·100 mL⁻¹·min⁻¹·s⁻¹). The results suggest that the lower peak exercise capacity in patients with moderate COPD is not related to a loss in leg vasodilatory capacity.     

Development, validation, and implementation of a questionnaire assessing disease knowledge and understanding in adult cystic fibrosis patients

BackgroundThe number of adults living with cystic fibrosis (CF) is increasing, necessitating an assessment of knowledge in this growing population.MethodsA questionnaire assessing CF knowledge was completed by 100 CF patients (median age: 26.0 years, range 17–49 years; median FEV₁: 57.0% predicted, range 20–127% predicted). Level of knowledge was correlated with clinical and sociodemographic characteristics.ResultsQuestionnaire validation showed acceptable internal consistency (α = 0.75) and test–retest reliability (0.94). Patients had fair overall understanding of CF (mean = 72.4%, SD = 13.1), with greater knowledge of lung and gastrointestinal topics (mean = 81.6%, SD = 11.6) than reproduction and genetics topics (mean = 57.9%, SD = 24.1). Females and those with post-secondary education scored significantly higher (p < 0.05).ConclusionsThis study validated a questionnaire that can be utilized to assess CF knowledge. Although CF patients understand most aspects of their disease, knowledge deficits are common – particularly regarding genetics and reproduction – and should be considered when developing CF education programs.     

Apparent Acute Reversible Right Ventricular Pacing‐Induced Left Ventricular Dysfunction

Apparent Acute Reversible Right Ventricular Pacing‐Induced Left Ventricular Dysfunction . We report the case of a 70‐year‐old Caucasian male with a dual chamber (right atrium/right ventricle) pacemaker implanted for sinus node dysfunction and not pacemaker (PM) dependent who was found to have an apparent acute worsening of left ventricular (LV) function with right ventricular (RV) apical pacing caused by the mode switch to VVI pacing as battery depletion occurred. LV dysfunction resolved immediately with RV pacing turned off. To our knowledge, this is the first report of this phenomenon. (J Cardiovasc Electrophysiol, Vol. 24, pp. 224‐226, February 2013)     

Coronary Angioplasty in Low Risk Patients with Low Dose Heparin and Immediate Withdrawal of the Femoral Sheath

This study reports our preliminary experience of percutaneous coronary angioplasty with low dose heparin and immediate withdrawal of the femoral sheath. After selection, 120 patients underwent a procedure with a low dose of heparin (4,300 ± 700 IU). A total of 120 of 123 lesions (97.6%) were treated successfully by the femoral route. There were no major cardiac complications during the procedure and hospital stay. Patients were allowed to be ambulant 6 hours after the procedure. No significant bleeding occurred. There was no need for surgery relative to the approach route nor for blood transfusion. The use of low dose heparin and immediate withdrawal of the femoral sheath did not increase the risk of coronary angioplasty in these selected patients. The period of bed confinement was shortened and the patients were ambulant earlier, leading to a reduction in their hospital stay with no increase in costs.     

贯叶金丝桃愈伤组织的诱导及其有效成分的定性

目的 :诱导出贯叶金丝桃的愈伤组织 ,并确定其中含有金丝桃素。方法 :在不同条件下采用组织培养技术 ,进行贯叶金丝桃的愈伤组织诱导研究 ,用HPLC方法确定其中含有的金丝桃素。结果和结论 :最佳诱导条件是MS基本培养基加入生长调节物质 2 ,4 D(4μg·L- 1 )和 6 BA(0 .2 μg·L- 1 )。叶腋等分生组织较多的部位易于诱导愈伤组织。诱导出的愈伤组织 ,经HPLC方法确定其含金丝桃素