The Usefulness of Magnetic Resonance Imaging in the Diagnosis of Anterolateral Impingement of the Ankle

The purpose of this study is to assess the sensitivity and specificity of magnetic resonance imaging (MRI) in the diagnosis of anterolateral impingement of the ankle and to assess the most helpful sequence in making the diagnosis. Twenty-four patients who had undergone ankle arthroscopy were chosen. Twelve patients had arthroscopically documented anterolateral impingement, and 12 patients with no impingement on arthroscopy served as controls. Two musculoskeletal radiologists and an orthopedic surgeon, blinded to the operative diagnosis, retrospectively reviewed selective MRI images in the sagittal, axial, and coronal planes. The sensitivities and specificities were calculated for all 3 reviewers. The Kendall coefficient of concordance was calculated for overall agreement among reviewers. Sensitivities varied from 0.75 to 0.83, whereas specificities varied from 0.75 to 1.00. Using the Fisher exact test of contingency, the sensitivities and specificities showed that all reviewers' interpretations were statistically significant with P = .039, .001, and .012, respectively. The axial images were felt to be most helpful in making the diagnosis. The physicians felt that the sagittal images were helpful in 67%, 83%, and 100%, respectively. MRI is a useful tool that can aid the clinician in the diagnosis of anterolateral impingement of the ankle. T1 sagittal images demonstrating displacement of the normal fat signal anterior to the fibula by scar can be useful and help to confirm the diagnosis.     

142Effects of Low‐Frequency Ultrasound Applied In Vitro to Highly Antibiotic‐Resistant Acinetobacter Isolates Recovered From Soldiers Returning From Iraq

Abstract  Brooke Army Medical Center isolated 25 highly antibiotic‐resistant Acinetobacter ssp . (primarily A. baumannii ) from wounded soldiers returning from Iraq. Concern about effective treatment of these organisms led our institution to begin investigating low‐frequency ultrasound (LFU) as a method of increasing the effectiveness of antibiotics on A.baumannii in wound management. Studies have suggested that LFU applied in conjunction with antibiotics may increase their overall effectiveness. We hypothesize that combining antibiotics with LFU may be an effective method of wound management and that this combination may be synergistic in its overall effect. In this initial work, we wanted to determine if sonocation would have an effect on our organism of interest, A. baumannii . We selected several organisms, both gram positive and gram negative, that have been shown to be killed by sonocation ( E. coli, S. aureus , and S. pyogenes ) and added three highly resistant A. baumannii isolates. Bacterial death was measured by both colony counts after 24 hours of growth and acridine orange staining using a standard protocol.
Colony counts were significantly reduced by sonocation. Furthermore, A.'baumannii colony counts were also greatly reduced by sonocation. Actual cell destruction was also visualized using acridine orange staining. Our data support the assertion that sonocation has an antibacterial effect on some bacteria, including A. baumannii . Our next step is to add antimicrobial agents and determine if their effectiveness can be increased by sonocation.     

Prudent strategies for elective red blood cell transfusion.

OBJECTIVE: To review the literature on the appropriateness of red blood cell transfusion and current physician practice, with emphasis on the physiologic and symptomatic implications of elective transfusion in the treatment of anemia. DATA SOURCES: Studies on the therapeutic use of red blood cell transfusion were identified through a search of MEDLINE (1966 to the present) and through a manual review of bibliographies of identified articles. In addition, evidence was solicited from selected experts in the field and recent consensus panels that have developed transfusion guidelines. DATA SYNTHESIS: No controlled trials of blood transfusion were identified, but data were available on four issues relevant to transfusion practice: current physician practice and evidence for excessive use of red blood cell transfusion; physiologic adaptation to anemia; human tolerance of low hemoglobin levels; and strategies for reducing homologous transfusion requirements. CONCLUSIONS: Despite the recent decline in red blood cell use because of concerns about infection, current transfusion practice remains variable because physicians have disparate views about its appropriateness. The remarkable human tolerance of anemia suggests that clinicians can accept hemoglobin levels above 70 g/L (7 g/dL) in most patients with self-limited anemia. In patients with impaired cardiovascular status or with anemias that will not resolve spontaneously, however, the data are insufficient to determine minimum acceptable hemoglobin levels, and therapy must be guided by the clinical situation. Several therapeutic strategies and pharmacologic interventions are available in the perioperative and non-operative settings to further reduce red blood cell use.     

Serum erythropoietin levels and blood component therapy after autologous bone marrow transplantation: implications for erythropoietin therapy in this setting.

To determine the potential impact of recombinant human erythropoietin (EPO) therapy in patients undergoing autologous bone marrow transplantation (BMT) and colony-stimulating factor therapy, we assayed endogenous serum EPO levels and noted blood transfusion requirements in relapsed non-Hodgkin's lymphoma patients treated with high-dose chemo-radiation therapy and autologous BMT. Hematocrit and reticulocyte counts were determined daily, and hematocrit was maintained in the 25-30% range by transfusion according to criteria established by our hospital transfusion committee. EPO levels were measured by radioimmunoassay and were determined at baseline, throughout therapy, and 2 and 3 months after BMT. Serum EPO levels increased more than 25-fold above baseline in most subjects after initiating chemoradiation therapy. No correlation was noted between serum EPO and hematocrit, reticulocyte count or serum creatinine. Total red blood cell units transfused ranged from 4 to 15 (mean 7.7). Mean total donor exposures (red blood cell plus platelet units transfused) were 83.6 units (range 16-175). Serum EPO levels increased early in the course of preparation for autologous BMT and remained elevated for at least 2-3 weeks thereafter although at a lower level. Red blood cell transfusions were required despite very high EPO levels after BMT. Red cell transfusions, moreover, accounted for only 9.2% (69 of 746) of total donor exposures and only 5.8% (42 of 746) of donor exposures during the interval when pharmacologic doses of erythropoietin might be of benefit. In contrast to the potential benefit of colony-stimulating factors such as G-CSF and GM-CSF in BMT, our study suggests limited value for erythropoietin therapy in this setting.     

Association between inflammation and epithelial damage-restitution processes in allergic airways in vivo

Background Associations between allergen challenge-induced sites of epithelial damage and the distribution of leucocytes and extravasated plasma remain unexplored. Objective To study neutrophils, eosinophils, and fibrinogen at allergen challenge-induced patchy epithelial damage-restitution sites in guinea-pig trachea. Methods After local challenge tracheal tissue (cryo sections and whole-mounts) and lumen (selective tracheal lavage) were examined at 1, 5, and 24 h. Eosinophils, neutrophils and fibrinogen were identified by histochemistry. Results Neutrophils increased markedly in tracheal lavage fluids and in tissue and were strongly associated with the challenge-induced epithelial craters of damage-restitution. At 1 and 24 h eosinophils were increased in the tracheal lumen whereas the surrounding tissue displayed a reversed pattern. Gels rich in fibrinogen, neutrophils, and eosinophils were present in epithelial crater areas, protruding into the lumen. Clusters of free eosinophil granules, Cfegs, released through lysis of eosinophils, and neutrophils with long cytoplasmatic protrusions abounded in these crater areas. Conclusions The present findings provide important new insights into allergic airways where sites of epithelial damage-restitution processes emerge as the major loci for eosinophil, neutrophil, and plasma protein activities, the latter likely causing leukocyte adhesion and activation in vivo. The disttibution of eosinophils in this study suggests roles of these cells both in airway mucosa and in regional lymph nodes. Based on the present study we also propose that lysis of eosinophils and Cfegs generation are a major paradigm for activation of these cells in vivo.     

鞍区肿瘤术后中枢性低钠血症的诊断和治疗

目的:探讨鞍区肿瘤术后中枢性低钠血症的诊断及处理方法。方法:对我科近四年鞍区肿瘤术后并发中枢性低钠血症的58例患者进行回顾性分析,术前、手术当日及术后每日定时检测血钠,观察尿量变化,测定中心静脉压,确定低钠血症的类型并给予相应的处理。结果:56例恢复正常,1例死于严重肺部感染,1例自动出院。结论:鞍区肿瘤易出现抗利尿激素分泌不当综合症和脑性耗盐综合症两种类型。前者需限水治疗,后者应予以充分补钠、补水,根据水、钠检测水平治疗。     

Novel proteins with binding specificity for DNA CTG repeats and RNA CUG repeats: implications for myotonic dystrophy

While an unstable CTG triplet repeat expansion is responsible for myotonic dystrophy, the mechanism whereby this genetic defect induces the disease remains unknown. To detect proteins binding to CTG triplet repeats, we performed bandshift analysis using as probes double- stranded DNA fragments having CTG repeats [ds(CTG)6-10] and single- stranded oligonucleotides having CTG repeats ss(CTG)8 or RNA CUG triplet repeats (CUG)8. The source of protein was nuclear and cytoplasmic extracts of HeLa cells, fibroblasts and myotubes. Proteins binding to the double-stranded DNA repeat [ds(CTG)6-10], were inhibited by nonlabeled ds(CTG)6-10, but not by a non-specific DNA fragment (USF/AD-ML). Another protein binding to ssCTG probe and RNA CUG probe was inhibited by nonlabeled (CTG)8 and (CUG)8. Nonlabeled oligos with different triplet repeat sequences, ss(CAG)8 or ss(CGG)8, did not inhibit binding to the ss(CTG)8 probe. However, when labeled as probes, the (CAG)8 and (CGG)8 bound to proteins distinct from the CTG proteins and binding was inhibited by nonlabeled (CAG)8 or (CGG)8 respectively. The protein binding only to the RNA repeat (CUG)8 was inhibited by nonlabeled (CUG)8 but not by nonlabeled single- or double-stranded CTG repeats. Furthermore, the CUG-BP exhibited no binding to an RNA oligonucleotide of triplet repeats of the same length but having a different sequence, CGG. The CUG binding protein was localized to the cytoplasm, whereas dsDNA binding proteins were localized to the nuclear extract. Thus, several trinucleotide binding proteins exist and their specificity is determined by the triplet sequence. The novel protein, CUG-BP, is particularly interesting since it binds to triplet repeats known to be present in myotonin protein kinase mRNA which is responsible for myotonic dystrophy.      

The effect of recombinant human erythropoietin therapy on red cell expansion during autologous blood donation

As the result of the institution of coordinated programs involving regional blood centers, hospital blood banks, information services, and physicians, preoperative autologous blood donation, a previously underutilized practice, has become a standard of care in a number of elective surgical procedures. In addition, the administration of recombinant human erythropoietin has been shown to facilitate the collection of autologous blood from patients scheduled for elective orthopaedic surgery. An analysis of the findings in a study of 263 orthopaedic surgical patients in which the relationship between autologous blood ordering, collection and storage, and subsequent blood transfusion was studied indicates that both blood ordering and blood procurement practices are significant factors with regard to allogeneic blood exposure.