Lichenoid histopathologic changes in patients with clinical diagnoses of exfoliative dermatitis.

Among 30 patients who received a clinical diagnosis of exfoliative dermatitis and were biopsied between 1982 and 1990, nine showed microscopic features of lichenoid dermatitis. Clinical information was available in eight of these cases. Possible etiologic factors included lymphoma, herpes simplex infection, connective tissue disease, and (in five cases) reactions to drugs. In each instance, microscopic features included a superficial perivascular lymphocytic infiltrate involving the dermal-epidermal interface, vacuolar alteration of the basilar layer, and individually necrotic keratinocytes at all levels of the epidermis. Such microscopic changes are not usually described in connection with exfoliative dermatitis, with the possible exception of those cases related to lichen planus or lupus erythematosus. Disseminated lichenoid drug eruption is one possible interpretation of the drug-induced cases. Erythema multiforme is another condition that has similar microscopic features and has been associated with drugs (many of which also cause exfoliative dermatitis), infectious agents, neoplasms, and connective tissue diseases. Lichenoid dermatitis can become generalized and clinically mimic and exfoliative dermatitis. Many, but not all, of these eruptions may be triggered by drugs.     

Assessing cervical dislocation as a humane euthanasia method in mice

Research investigators often choose to euthanize mice by cervical dislocation (CD) when other methods would interfere with the aims of a research project. Others choose CD to assure death in mice treated with injected or inhaled euthanasia agents. CD was first approved for mouse euthanasia in 1972 by the AVMA Panel on Euthanasia, although scientific assessment of its humaneness has been sparse. Here we compared 4 methods of spinal dislocation--3 targeting the cervical area (CD) and one the thoracic region--in regard to time to respiratory arrest in anesthetized mice. Of the 81 mice that underwent CD by 1 of the 3 methods tested, 17 (21%) continued to breathe, and euthanasia was scored as unsuccessful. Postmortem radiography revealed cervical spinal lesions in 5 of the 17 cases of unsuccessful CD euthanasia. In addition, 63 of the 64 successfully euthanized mice had radiographically visible lesions in the high cervical or atlantooccipital region. In addition, 50 of 64 (78%) mice euthanized successfully had radiographically visible thoracic or lumbar lesions or both. Intentionally creating a midthoracic dislocation in anesthetized mice failed to induce respiratory arrest and death in any of the 18 mice subjected to that procedure. We conclude that CD of mice holds the potential for unsuccessful euthanasia, that anesthesia could be valuable for CD skills training and assessment, and that postmortem radiography has minimal promise in quality-control assessments.     

Reduction in Postoperative High-Density Lipoprotein Cholesterol Levels in Children Undergoing the Fontan Operation

Despite the emerging relevance of high-density lipoprotein (HDL) in the inflammatory cascade and vascular barrier integrity, HDL levels in children undergoing cardiac surgery are unexplored. As a measure of HDL levels, the HDL-cholesterol (HDL-C) in single-ventricle patients was quantified before and after the Fontan operation, and it was determined whether relationships existed between the duration and the type of postoperative pleural effusions. The study prospectively enrolled 12 children undergoing the Fontan operation. Plasma HDL-C levels were measured before and after cardiopulmonary bypass. The outcome variables of interest were the duration and type of chest tube drainage (chylous vs. nonchylous). The Kendall rank correlation coefficient and the Wilcoxon rank sum test were used. There were 11 complete observations. The median preoperative HDL-C level for all the subjects was 30?mg/dl (range, 24-53?mg/dl), and the median postcardiopulmonary bypass level was 21?mg/dl (range, 14-46?mg/dl) (p?=?0.004). There was a tendency toward a moderate inverse correlation (-0.42) between the postcardiopulmonary bypass HDL-C level and the duration of chest tube drainage, but the result was not statistically significant (p?=?0.07). In the chylous effusion group, the median postcardiopulmonary bypass HDL-C tended to be lower (16 vs. 23?mg/dl; p?=?0.09). After the Fontan operation, the plasma HDL-C levels in children are significantly reduced. It is reasonable to conclude that the reduction in HDL-C reflects reduced plasma levels of HDL particles, which may have pertinent implications in postoperative pleural effusions given the antiinflammatory and endothelial barrier functions of HDL.     

Sensitivity of Bedside Ultrasound and Supine Anteroposterior Chest Radiographs for the Identification of Pneumothorax After Blunt Trauma

Objectives: Supine anteroposterior (AP) chest radiographs in patients with blunt trauma have poor sensitivity for the identification of pneumothorax. Ultrasound (US) has been proposed as an alternative screening test for pneumothorax in this population. The authors conducted an evidence‐based review of the medical literature to compare sensitivity of bedside US and AP chest radiographs in identifying pneumothorax after blunt trauma. Methods: MEDLINE and EMBASE databases were searched for trials from 1965 through June 2009 using a search strategy derived from the following PICO formulation of our clinical question: patients included adult (18 + years) emergency department (ED) patients in whom pneumothorax was suspected after blunt trauma. The intervention was thoracic ultrasonography for the detection of pneumothorax. The comparator was the supine AP chest radiograph during the initial evaluation of the patient. The outcome was the diagnostic performance of US in identifying the presence of pneumothorax in the study population. The criterion standard for the presence or absence of pneumothorax was computed tomography (CT) of the chest or a rush of air during thoracostomy tube placement (in unstable patients). Prospective, observational trials of emergency physician (EP)‐performed thoracic US were included. Trials in which the exams were performed by radiologists or surgeons, or trials that investigated patients suffering penetrating trauma or with spontaneous or iatrogenic pneumothoraces, were excluded. The methodologic quality of the studies was assessed. Qualitative methods were used to summarize the study results. Data analysis consisted of test performance (sensitivity and specificity, with 95% confidence intervals [CIs]) of thoracic US and supine AP chest radiography. Results: Four prospective observational studies were identified, with a total of 606 subjects who met the inclusion and exclusion criteria. The sensitivity and specificity of US for the detection of pneumothorax ranged from 86% to 98% and 97% to 100%, respectively. The sensitivity of supine AP chest radiographs for the detection of pneumothorax ranged from 28% to 75%. The specificity of supine AP chest radiographs was 100% in all included studies. Conclusions: This evidence‐based review suggests that bedside thoracic US is a more sensitive screening test than supine AP chest radiography for the detection of pneumothorax in adult patients with blunt chest trauma. ACADEMIC EMERGENCY MEDICINE 2010; 17:11–17 © 2010 by the Society for Academic Emergency Medicine     

Transcutaneous oxygen measurements predict a beneficial response to hyperbaric oxygen therapy in patients with nonhealing wounds and critical limb ischemia.

Hyperbaric oxygen (HBO) therapy may be a useful adjunct in the treatment of patients with wounds associated with critical limb ischemia. These patients either cannot undergo a successful bypass or may not heal after vascular reconstruction alone. Identification of patients likely to benefit from HBO is essential before treatment, as this therapy is time-consuming, costly, and not without risk. Transcutaneous oxygen measurements (TCOM) can be used to evaluate the degree of hypoxia in ischemic tissue. In this study we evaluated whether TCOM could be used to identify those patients who would or would not benefit from HBO therapy. Our hypothesis is that a difference in transcutaneous oxygen tension readings measured near the ischemic lesion with the patient breathing room air and while breathing 100 per cent oxygen at ambient pressure may be predictive of wound healing with adjunctive hyperbaric oxygen therapy. Thirty-six patients with critical limb ischemia and nonhealing ulcers were referred for HBO therapy. They were deemed either nonreconstructible from a vascular surgical viewpoint, had failed prior revascularization attempts, or could not achieve complete wound healing even after a successful revascularization. Pretreatment assessment included a room air and post-100 per cent-O2 challenge TCOM reading obtained in the vicinity of the open wound. Hyperbaric oxygen treatments at 2.0 to 2.5 atm were then administered until healing occurred or failure was confirmed. All patients undergoing HBO had a baseline TCOM of <40 torr. Twenty-seven patients had an increase in TCOM of >10 torr with oxygen inhalation at initial evaluation. Of these patients, 19 (70%) healed their wounds with HBO therapy. Conversely the increase in TCOM was <10 torr in nine patients, and only one of these patients (11%) ultimately healed (P < 0.01). Patients with nonhealing ischemic extremity wounds may heal with adjunctive HBO therapy. We can predictably identify patients who are likely to benefit from this modality using TCOM at the time of initial evaluation. An increase of tissue O2 tension of > or =10 torr when breathing pure O2 suggests that the patient may benefit from HBO therapy. Those patients with an increase of <10 torr are unlikely to receive benefit from this treatment modality.     

Preparedness for caring of cancer survivors: A multi-institutional study of medical students and oncology fellows

Background. Despite recent advances in cancer survivorship knowledge and care, most medical schools lack a comprehensive survivorship curriculum, potentially leaving students ill-prepared for caring of survivors. Methods. A total of 211 students and 22 oncology fellows in 3 institutions completed a questionnaire assessing knowledge and experience in survivorship care. Results. Medical students and oncology fellows lack knowledge in key survivorship issues. Students were exposed to cancer survivors frequently in medical school but only half received instruction or practiced critical components of survivorship care. Conclusions. Improvement of both undergraduate and postgraduate training in survivorship care is urgently warranted.     

葛根素的心血管系统药理作用及机理研究

纵观近年来对葛根素在心血管系统药理作用及机理研究方面的进展发现，葛根素对心血管系统具有抗心律失常、降血压、扩张冠状动脉、抗心肌缺血、抗过氧化、抗缺血-再灌注损伤、影响血液动力学和血小板聚集、保护血管等作用。其临床应用前景良好，其药效机制研究及临床应用有待更深一步的探究。