APOE, APOE promoter, and Tau genotypes and risk for concussion in college athletes.

OBJECTIVE: To investigate associations of APOE, APOE promoter (G-219T), and tau protein exon 6 polymorphisms (47 and 53) and a history of self-reported concussion in college athletes. DESIGN: Multi-center cross-sectional study. SETTING: Male football and male and female soccer programs at the University of South Carolina, Jacksonville University, Benedict College, and the College of Charleston. PARTICIPANTS: Active 18- to 30-year-old (n = 195) intercollegiate male football players and male and female soccer players during 2001 and 2002. ASSESSMENT OF RISK FACTORS: Written questionnaires and blood or mouthwash samples for DNA for genotyping by RFLP/PCR. MAIN OUTCOME MEASUREMENT: Self-reported history of concussions over the previous 8 years. RESULTS: A statistically significant, nearly 3-fold increase in risk of a history of concussion for those with the APOE promoter G-219T TT genotype relative to the GG genotype (OR, 2.8; 95% CI, 1.1 to 6.9) adjusted for age, sport, school, and years in their primary sport, a finding that was stronger for Cantu grade 2 and 3 concussions. CONCLUSIONS: These results suggest that college athletes with an APOE promoter G-219T TT genotype may be at increased risk for having a history of concussions, especially more severe concussions. Although there was some support for the possibility that the tau 53 polymorphism may be associated with increased risk of prior concussion (OR, 2.1; 95% CI, 0.3 to 14.5), there was no support for an association with APOE genotypes. The results of this cross-sectional study support the need for a prospective study of genetic factors, such as APOE promoter polymorphisms, and the incidence of and sequelae from concussions in college athletes.     

Pulmonary embolism after hip or knee replacement: postoperative changes on pulmonary scintigrams in asymptomatic patients

Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients.     

Accuracy of digital imaging interpretation on an 1K × 1K PC-based workstation in the emergency department

The purpose of this study was to evaluate the accuracy of interpretation of digital radiographs on 1K × 1K PC-based workstations and compare it to that of 2K × 2K workstations in our filmless emergency department. We reviewed 1013 studies, of which 404 were chest, 133 abdominal, and 476 musculoskeletal. All studies were interpreted prospectively on the 1K × 1K workstation, and the findings were compared to those on the 2K × 2K diagnostic workstation which served as the control. Among all the studies performed, 515 were negative (255 chest, 91 abdominal, and 169 musculoskeletal). Another 498 had positive findings (149 chest, 42 abdominal, and 307 musculoskeletal). When the cases were reviewed on the 1K × 1K monitor, the diagnosis was missed in 5 of the 149 positive chest cases (3.35 %), in 5 of the 307 positive musculoskeletal cases (1.63 %), and in none of the 42 positive abdominal cases (0 %). In total, we misinterpreted 10 of the 498 positive cases (2.01 %). The miss rate of the 1K × 1K clinicians' review station is low and acceptable for its stated purpose. However, we doubt that it can be used for primary diagnostic purposes.     

Colonoscopy in the patient requiring anticoagulation

PURPOSE: The aim of this study was to assess perioperative warfarin management and complications in patients requiring colonoscopy. METHODS: We retrospectively reviewed 109 cases of colonoscopies performed on 94 patients requiring anticoagulation with warfarin. Patients stopped their warfarin three days before colonoscopy. Coagulation profiles obtained just before the colonoscopy showed a median prothrombin time of 13.4 seconds with a range of 11.1 to 29.1 (normal range, 10.9–13) and a median international normalized ratio of 1.2 with a range of 0.9 to 2.6. Patients restarted warfarin the day after the examination. RESULTS: During the 109 colonoscopies, 47 percent of the patients underwent either hot biopsy or snare polypectomy. One examination that included several biopsies was associated with a hemorrhagic complication (0.92 percent) requiring hospitalization and transfusion. Subset analysis of the therapeutic (biopsy and snare polypectomy) group indicated a slightly higher complication rate (1.96 percent) with a median international normalized ratio of 1.3 (range, 1–2.3) and a median prothrombin time of 13.7 (range, 11.6–25.9). CONCLUSION: Patients taking warfarin for anticoagulation may safely undergo colonoscopy. The risk of hemorrhagic complications increases slightly with hot biopsy or snare procedures. Further studies are needed to refine guidelines for colonoscopy in the patient requiring anticoagulation.Poster presentation at The American Society of Colon and Rectal Surgeons' 100th Anniversary and Tripartite Meeting, Washington D.C., May 1 to 6, 1999.     

Kinetics of peripheral blood mononuclear cell mobilization with chemotherapy and/or granulocyte-colony-stimulating factor: implications for yield of hematopoietic progenitor cell collections

BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies.     

预激态补骨脂素抑制 K562细胞增殖的实验研究

本研究的目的是观察预激态补骨脂素对K562细胞增殖的影响，为补骨脂素的临床应用提供实验依据。取预激态补骨脂素和晚激态补骨脂素处理的细胞，在培养后检测台盼蓝拒染细胞数和白血病细胞集落，并对它们在台盼蓝拒染细胞抑制率(TBIR)、细胞增殖抑制率(CPIR)和集落形成抑制率(CFIR)方面的差异进行比较。结果表明：预激态补骨脂素对K562细胞增殖有抑制作用；随着预激态补骨脂素浓度的增加，其抑制作用也随之增强；预激态补骨脂素与晚激态补骨脂素的TBIR、CPIR、CFIR各值比的差异不显著；为使预激态补骨脂素要充分发挥对K562细胞的抑制作用，补骨脂素的紫外线照射时间应在10分钟以上；与K562细胞作用时间也应大于12小时；抑制作用会因预激态补骨脂素预激后搁置时间的延长而下降，在6小时内作用最强。结论：预激态补骨脂素和晚激态补骨脂素对K562细胞的增殖均表现出抑制作用，有望作为临床的抗肿瘤用药。