超低频振动对人体影响的研究

为研究超低频振动对人的视力、操作能力、胃电图、人体平衡稳定性和主观感觉的影响。实验采用０．２５、０．５、０．６３、０．８和１．０Ｈｚ五个振动频率，并参考之轴振动（头－足向）运动病频率范围，将实验结果按三个频段进行了分析。被试者取半仰卧位。结果表明，视力、操作能力、平衡稳定性不但与频率有关，而且随振动加速度的增加而降低。除视力外，它们随频率变化的规律符合所分频段含义，胃电图主频率改变和主观感觉级测试进一步说明了这一点。０．２５Ｈｚ不仅处在Ｚ轴全身振动的运动病敏感频段，而且也是Ｘ轴全身振动的敏感频率。因此，载人航天飞行中，不仅应避开０．２５Ｈｚ的Ｚ轴全身振动，而且也应避开０．２５Ｈｚ的ｘ轴全身振动。     

Temporal expression of urokinase plasminogen activator, plasminogen activator inhibitor and gelatinase-B in chronic wound fluid switches from a chronic to acute wound profile with progression to healing

The plasminogen activator/plasmin system is known to initiate a proteolytic cascade resulting in the activation of matrix metalloproteinases in vitro leading to the degradation of extracellular matrix. To investigate whether or not this cascade is present during delayed wound healing and contributes to the pathophysiological basis of impaired healing we examined the temporal expression of urokinase plasminogen activator, plasminogen activator inhibitor-1 and gelatinase-B in fluid collected from chronic venous leg ulcers compared to acute surgical mastectomy wounds. Using a chromogenic substrate assay, levels of active urokinase plasminogen activator in chronic wounds were found to be about five fold higher compared to sera and two fold higher compared to mastectomy wounds. Levels of active plasminogen activator inhibitor-1 in chronic wounds were four times higher than those found in sera and two times higher than those found in mastectomy wound fluid. Using a fibrin overlay system and reverse zymography, we found that when the wound was not healing, the expression of urokinase plasminogen activator in chronic wound fluid was initially detected in the active forms (50 and 33 kDa), but that as the wound healed and decreased in size, was detected as an inhibitor- bound urokinase plasminogen activator-plasminogen activator inhibitor-1 complex ( congruent with 80-116 kDa). When the expression of active urokinase plasminogen activator was highest, no plasminogen activator inhibitor-1 was detectable. In contrast, urokinase plasminogen activator was always detected in the inhibitor bound form as a urokinase plasminogen activator-plasminogen activator inhibitor-1 complex in blood- and plasma-derived serum and mastectomy wound fluid. Plasminogen activator inhibitor-1 was detected in blood-derived serum and mastectomy wound fluid but not in plasma derived serum. Expression of matrix metalloproteinase-9 in chronic wound fluids, analyzed by gelatin zymography, showed that when urokinase plasminogen activator was detected in the active forms, matrix metalloproteinase-9 was overexpressed by approximately twice that found in mastectomy wounds and approximately 30 times that detected in blood-derived sera. When urokinase plasminogen activator appeared almost entirely as an enzyme- inhibitor complex, the level of expression of matrix metalloproteinase-9 was similar to that seen in mastectomy wound fluid. We conclude that the switch in urokinase plasminogen activator expression from an active to inhibitor bound form correlates with the decrease seen in matrix metalloproteinase-9 expression suggesting the presence of a proteolytic cascade initiated by the plasminogen activator/plasmin system during wound healing leading to the activation of matrix metalloproteinase-9. In addition, expression of urokinase plasminogen activator and matrix metalloproteinase-9 appear to be useful biomarkers to determine clinical wound healing status.     

Limited M1 Disease: A Significant Prognostic Factor for Stage IV Breast Cancer

Purpose

The prognosis of patients with breast cancer presenting with distant metastasis can vary depending on disease extent. This study evaluates a definition of limited M1 disease in association with survival in a cohort of women presenting with metastatic breast cancer.

Methods

The study cohort comprised 692 women referred to the BC Cancer Agency between 1996 and 2005 with M1 breast cancer at presentation. Limited M1 disease was defined as <5 metastatic lesions confined to one anatomic subsite. Extensive M1 disease was defined as ??5 lesions or disease in more than one subsite. Clinicopathologic and treatment characteristics and overall survival (OS) were compared between subjects with limited (n?=?233) versus extensive (n?=?459) M1 disease. Multivariable analysis was performed by Cox regression modeling.

Results

Median follow-up time was 1.9?years. Five-year Kaplan-Meier OS was significantly higher in patients with limited compared to extensive M1 disease (29.7 vs. 13.1?%, p?p?Conclusions Limited M1 disease, defined as <5 metastatic lesions confined to one anatomic subsite, is a relevant favorable prognostic factor in patients with stage IV breast cancer. This definition may be used in conjunction with other clinicopathologic factors to select patients for more aggressive systemic and locoregional treatments.     

Histopathologic staining of low temperature cutaneous burns: Comparing biomarkers of epithelial and vascular injury reveals utility of HMGB1 and hematoxylin phloxine saffron

Histopathology remains the gold standard for evaluation of burn depth, progression, and healing, but burn literature offers little guidance on the best stains for analysis of these complex and evolving injuries. A battery of histochemical and immunohistochemical stains was compared on adjacent sections to determine the best stains for histopathologic study and imaging of burns. Using a validated porcine model of vertical burn progression, full‐thickness cutaneous biopsies were stained using hematoxylin and eosin, Hematoxylin phloxine saffron (HPS), Masson Trichrome, Elastin Von Gieson, Movatt's Pentachrome, vimentin, CD31, KI‐67, caspase 3a, and high mobility group box 1. Depth of collagen degeneration, cellular necrosis, apoptosis, and vascular occlusion; and reparative processes of cellular hyperplasia, reepithelialization, and new collagen deposition were measured by ocular microscopy. High mobility group box 1 was superior for necrosis between 1 and 24 hours postburn. Vimentin underestimated necrosis until 48 hours postburn. For overall assessment, hematoxylin and eosin and HPS were comparable, except for analysis of thermally injured collagen, vessel occlusion, erythrocyte extravasation, and polariscopic study of collagen deposition, where HPS was superior. HPS stain offers specific advantages in histopathologic burn analysis. Inexpensive and rapid to produce, HPS allows users to analyze eosinophilic components more precisely than standard hematoxylin and eosin.     

Racial Disparities in Depression and Life Satisfaction After Spinal Cord Injury: A Mediational Model

Purpose:

To identify the relationship of race and gender with 3 aspects of life satisfaction and depressive symptoms after spinal cord injury (SCI), evaluating the extent to which socioeconomic factors mediate any observed relationships.

Methods:

Adults with traumatic SCI of at least 1-year duration (N = 1,549) were identified through a Southeastern United States SCI Model System of care, and cross-sectional survey data were collected at a Southeastern United States medical university. Three aspects of life satisfaction (home life satisfaction, vocational satisfaction, global satisfaction) were measured using 20 satisfaction items from the Life Situation Questionnaire-Revised. The Older Adult Health and Mood Questionnaire measured depressive symptoms. MANCOVA assessed mediation of socioeconomic status between race and life satisfaction and depression.

Results:

Home life satisfaction and vocational satisfaction were significantly related to race, with White participants scoring higher than Black participants during the first stage of the regression. However, socioeconomic factors mediated the relationships such that race was no longer significant after considering economic factors. Race was significantly associated with global satisfaction after adjusting for socioeconomic factors. Depression was not significantly related to race. Gender was unrelated to all study outcomes. Of the socioeconomic mediators, family income was a significant predictor of each outcome, whereas education was only predictive of vocational satisfaction.

Conclusion:

Socioeconomic factors are important mediators of the relationship between race and certain aspects of life satisfaction among persons with SCI. Family income and, to a lesser extent, education should be considered when evaluating race differences in life satisfaction after SCI.     

Dysphagia and Associated Respiratory Considerations in Cervical Spinal Cord Injury

Background:

Dysphagia is a relatively common secondary complication that occurs after acute cervical spinal cord injury (SCI). The detrimental consequences of dysphagia in SCI include transient hypoxemia, chemical pneumonitis, atelectasis, bronchospasm, and pneumonia. The expedient diagnosis of dysphagia is imperative to reduce the risk of the development of life-threatening complications.

Objective:

The objective of this study was to identify risk factors for dysphagia after SCI and associated respiratory considerations in acute cervical SCI.

Methods:

Bedside swallow evaluation (BSE) was conducted in 68 individuals with acute cervical SCI who were admitted to an SCI specialty unit. Videofluroscopy swallow study was conducted within 72 hours of BSE when possible.

Results:

This prospective study found dysphagia in 30.9% (21 out of 68) of individuals with acute cervical SCI. Tracheostomy (P = .028), ventilator use (P = .012), and nasogastric tube (P = .049) were found to be significant associated factors for dysphagia. Furthermore, individuals with dysphagia had statistically higher occurrences of pneumonia when compared with persons without dysphagia (P < .001). There was also a trend for individuals with dysphagia to have longer length of stay (P = .087).

Conclusion:

The role of respiratory care practitioners in the care of individuals with SCI who have dysphagia needs to be recognized. Aggressive respiratory care enables individuals with potential dysphagia to be evaluated by a speech pathologist in a timely manner. Early evaluation and intervention for dysphagia could decrease morbidity and improve overall clinical outcomes.     

老年高血压患者血压昼夜节律对左室肥厚的影响

【摘要】 目的 研究老年高血压患者的血压昼夜节律变化对左室肥厚的影响。方法 选取我院126例高血压患者,根据心脏彩超提示左室肥厚情况分为肥厚组（n=52例）和非肥厚组（n=74例）。比较两组动态血压指标及血压变异性,进行多因素分析探讨血压变异性对左室肥厚的影响。 结果 高血压肥厚组24h平均收缩压（24hSBP）、白天平均收缩压（dSBP）、夜间平均收缩压（nSBP）、24h收缩压标准差（24hSSD）、24h舒张压标准差（24hDSD）、白天收缩压标准差（dSSD）、夜间收缩压标准差（nSSD）均高于非肥厚组,差异有统计学意义（P＜005）。Logistic回归分析显示,24h SBP 与dSSD、nSSD为左室肥厚的独立危险因素（P＜005）。结论 老年高血压患者的24h SBP 与dSSD、nSSD是影响左室肥厚的独立危险因素,平稳控制血压对防止左室肥厚的发生有一定影响。     

小肠间质瘤20例诊治分析

目的　总结小肠间质瘤诊断和治疗经验。方法　对1993—2 0 0 4年收治的2 0例小肠间质瘤的临床资料进行回顾性分析。结果　临床表现为黑便、果酱样血便14例、头晕9例、贫血3例,伴腹部疼痛11例,发病时间2个月至7年。确诊方式:剖腹探查12例,腹腔镜探查6例,小肠镜检查2例;手术方式:小肠间质瘤切除18例,胰十二指肠切除术1例,肿瘤无法切除行保守治疗1例。随访6个月至9年,除1例死于脑干出血、2例长期服用甲磺酸伊马替尼(Gleevec)症状部分缓解外,其余17例均健在,间质瘤无复发。结论　小肠间质瘤预后较好,但对不明原因的消化道出血应及早探查,以避免误诊;Gleevec对晚期小肠间质瘤有较好疗效