肩、肘关节外科新进展

肩关节（Shoulder） 旋转袖（Rotator Cuff） 基础研究（Basic Science） Zuckerman讨论了软骨诱导形态发生蛋白-2（cartilagederived morphogenetic protein-2，CDMP-2）的早期工作。在鼠肌腱修复中，4周时CDMP-2治疗组的修复强度高于未治疗组。Dines讨论了关于血小板衍生生长因子（platelet—derived growth factor，PDGF）和胰岛素样生长因子-1（insulin-like growth factor-1，IGF-1）最初的研究观察。     

7-甲氧基-4′-羟基-3′-二乙胺甲基异黄酮(MHDF)对大鼠血流动力学和主动脉的作用

本实验观察了MHDF对整体大鼠血流动力学和离体大鼠胸主动脉的作用。结果表明iv MHDF(3～12.8 mg/kg)能降低大鼠左心室±dp/dt_max,V_max,V_pm和LVSP,延长T-dp/dt_max,减慢心率。MHDF还能舒张大鼠胸主动脉,ED₅₀为6.5×10^-6mol/L;非竞争拮抗NA和CaCl₂致主脉收缩,pD₂′为3.11±0.21和3.73±0.07;抑制高K⁺致主动脉收缩,IC₅₀为1.76×10^-5mol/L。提示MHDF对血管的作用与α受体阻断剂不同,而可能与钙拮抗有关。     

Repetitive, negligible force reaching in rats induces pathological overloading of upper extremity bones.

Work-related repetitive motion disorders are costly. Immunohistochemical changes in bones resulting from repetitive reaching and grasping in 17 rats were examined. After 3-6 weeks, numbers of ED1+ macrophages and osteoclasts increased at periosteal surfaces of sites of muscle and interosseous membrane attachment and metaphyses of reach and nonreach forelimbs. These findings indicate pathological overloading leading to inflammation and subsequent bone resorption. INTRODUCTION: Sixty-five percent of all occupational illnesses in U.S. private industry are attributed to musculoskeletal disorders arising from the performance of repeated motion, yet the precise mechanisms of tissue pathophysiology have yet to be determined for work-related musculoskeletal disorders. This study investigates changes in upper extremity bone tissues resulting from performance of a voluntary highly repetitive, negligible force reaching and grasping task in rats. MATERIALS AND METHODS: Seventeen rats reached an average of 8.3 times/minute for 45-mg food pellets for 2 h/day, 3 days/week for up to 12 weeks. Seven rats served as normal or trained controls. Radius, ulna, humerus, and scapula were collected bilaterally as follows: radius and ulna at 0, 3, 4, 5, 6, and 12 weeks and humerus and scapula at 0, 4, and 6 weeks. Bones were examined for ED1-immunoreactive mononuclear cells and osteoclasts. Double-labeling immunohistochemistry was performed for ED1 (monocyte/macrophage lineage cell marker) and TRACP (osteoclast marker) to confirm that ED1+ multinucleated cells were osteoclasts. Differences in the number of ED1+ cells over time were analyzed by ANOVA. RESULTS: Between 3 and 6 weeks of task performance, the number of ED1+ mononuclear cells and osteoclasts increased significantly at the periosteal surfaces of the distal radius and ulna of the reach and nonreach limbs compared with control rats. These cells also increased at periosteal surfaces of humerus and scapula of both forelimbs by 4-6 weeks. These cellular increases were greatest at muscle attachments and metaphyseal regions, but they were also present at some interosseous membrane attachments. The number of ED1+ cells decreased to control levels in radius and ulna by 12 weeks. CONCLUSIONS: Increases in ED1+ mononuclear cells and osteoclasts indicate that highly repetitive, negligible force reaching causes pathological overloading of bone leading to inflammation and osteolysis of periosteal bone tissues.     

Relation of latex-specific IgE titer and symptoms in patients allergic to latex

BACKGROUND: The relation between latex-specific IgE titer and the type or total number of latex-induced symptoms has not been previously investigated. OBJECTIVE: We sought to determine the association of latex-IgE in vitro assay results with the type, number, or severity of symptoms in patients allergic to latex. METHODS: Ninety-one patients with positive histories and positive skin test responses were identified as having type I allergy. Data was collected for reported symptoms after latex exposure. Symptom severity was quantitated by 2 scores: (1) the total number of symptoms to latex exposure and (2) a symptom severity score (3 = anaphylaxis, 2 = asthma, and 1 = rhinoconjunctivitis, urticaria, or both). All subjects underwent AlaSTAT and CAP tests. RESULTS: AlaSTAT class was associated with total number of symptoms (r = 0.32, P <.001) and severity score (r = 0.33, P <.002). Similarly, CAP class was associated with both number of symptoms (r = 0.32, P <. 0001) and severity score (r = 0.31, P <.001). Among the symptoms reported, asthma had the strongest association with a positive in vitro IgE assay (odds ratio = 6.7 [95% confidence interval = 1.9, 25. 6]), followed by urticaria (odds ratio = 1.9 [95% confidence interval = 0.8, 4.6]). Contact dermatitis had no statistical association with in vitro assays in this study. AlaSTAT and CAP class correlated together significantly (r = 0.58, P <.001). CONCLUSION: Patients allergic to latex with higher AlaSTAT or CAP class were more symptomatic. Increasing class or titer also predicted more severe symptoms. Higher class of either the AlaSTAT or CAP assay to latex was strongly associated with latex-related asthma and urticaria and marginally associated with latex-related rhinoconjunctivitis.     

Frequency and significance of complete atrioventricular block after coronary artery bypass grafting

Three hundred forty-eight consecutive patients were evaluated during 1985 and 1986 for the development of complete atrioventricular (AV) block after coronary artery bypass grafting. Cold (4 degrees) asanguineous potassium cardioplegia with temperature monitoring was used uniformly. AV block developed in 56 instances (16%). In 32 patients (group 1) the block was transient (less than 6 hours) and in 24 it was persistent (group 2). Left main coronary artery stenosis in conjunction with total obstruction of a dominant right coronary artery occurred more commonly in patients manifesting AV block (18 of 56, 32%) than in those without it (35 of 292, 12%) (p less than 0.05). Complete occlusion of a dominant right coronary artery was observed with equal frequency in patients with and without AV block. The presence of an ungraftable right coronary artery, however, was significantly more frequent in the AV block group: 16 of 37 (47%) vs 6 of 194 (3%) (p less than 0.01). Endarterectomy of the right coronary artery was performed in 8 of 24 patients (33%) with persistent AV block versus none in the patients with transient AV block (n = 32) or normal sinus rhythm postoperatively (n = 292) (p less than 0.0001). Persistent AV block (greater than 6 hours) was associated with myocardial infarction in 6 patients (25%) (p less than 0.05) and with low cardiac output in 18 patients (75%) (p less than 0.0001). In conclusion, AV block after myocardial revascularization was frequently associated with the presence of multivessel coronary disease and an ungraftable dominant right coronary artery. Persistent (greater than 6 hours) AV block was correlated with both perioperative myocardial infarction and low cardiac output.