Measurement of kinetic parameters in skeletal muscle by magnetic resonance imaging with an intravascular agent.

The purpose of this work was to investigate the use of an intravascular contrast agent to determine perfusion kinetics in skeletal muscle. A two-compartment kinetic model was used to represent the flux of contrast agent between the intravascular space and extravascular extracellular space (EES). The relationship between the image signal-to-noise ratio (SNR) and errors in estimating permeability surface area product (Ktrans), interstitial volume (ve), and plasma volume (vp) for linear and nonlinear curve-fitting methods was estimated from Monte Carlo simulations. Similar results were obtained for both methods. For an image SNR of 60, the estimated errors in these parameters were 10%, 22%, and 17%, respectively. In vivo experiments were conducted in rabbits to examine physiological differences between these parameters in the soleus (SOL) and tibialis anterior (TA) muscles in the hind limb. Values for Ktrans were significantly higher in the SOL (3.2+/-0.9 vs. 2.0+/-0.5x10(-3) min-1), as were values for vp (3.4+/-0.8 vs. 2.1+/-0.7%). Differences in ve for the two muscles (8.7+/-2.2 vs. 8.5+/-1.6%) were not found to be significant. These results demonstrate that relevant physiological metrics can be calculated in skeletal muscle using MRI with an intravascular contrast agent.     

Etanercept decreases tumor necrosis factor-α activity in chronic wound fluid

High levels of tumor necrosis factor-alpha (TNF-alpha), a pro-inflammatory cytokine, are present in the wound fluid of chronic nonhealing wounds. This leads to increased inflammation, cytokine expression, and ultimately results in impaired wound healing and tissue destruction. Etanercept is a recombinant fusion protein that consists of the soluble TNF receptor (p75) linked to the Fc portion of human IgG1. It is an effective inhibitor of TNF-alpha and has been shown to provide rapid and sustained improvement in rheumatoid arthritis by acting as a soluble receptor binding TNF-alpha and preventing its proinflammatory activities. Therefore, the aim of this study was to determine whether Etanercept could inhibit TNF-alpha activity in chronic wound fluid. Wound fluid was collected from the venous leg ulcers of 16 different patients. The effect of Etanercept on TNF-alpha activity was evaluated using both a TNF-alpha bioassay and an enzyme-linked immunoassay. Etanercept was found to reduce the cytotoxic effect of chronic wound fluid on L929 fibroblasts by approximately 30% and neutralized TNF-alpha binding in the enzyme-linked immunoassay by up to 80%. Direct application of Etanercept to chronic wounds may therefore reduce the inflammatory activity of TNF-alpha, which could reduce the chronicity of venous leg ulcers and thus aid in the healing of these wounds.     

PTEN及Bcl-2蛋白在膀胱移行细胞癌中的表达及其意义

目的：探讨PTEN及Bcl-2蛋白在膀胱移行细胞癌的表达规律及其临床意义。方法：应用免疫组织化学链亲和素-生物素-霉复合物（SP）方法检测43例膀胱移行细胞癌和7例正常黏膜组织中PTEN及Bcl-2蛋白的表达．分析二者的表达与膀胱癌病理参数的关系。结果：（1）G1、G2、G3肿瘤PTEN表达阳性率分别为85．7％、80．4％、73．3％，浸润性肿瘤和表浅性肿瘤表达阳性率分别为70．4％和93．8％，说明PTEN表达阳性率与肿瘤病理分级、临床分期有关。（2）G。、G2、G3肿瘤Bcl-2表达阳性率分别为14．2％、57．14％、66．67％，浸润性肿瘤和表浅性肿瘤表达阳性率分别为59．3％和43．8％，说明Bcl-2表达阳性率与肿瘤病理分级、临床分期有关。（3）随着肿瘤恶性程度的增高和临床分期进展，PTEN蛋白阳性率呈下降，Bcl-2表达呈增高趋势，二者表达呈负相关关系。结论：PTEN的抑癌作用可能与Bcl-2有关．二者的异常表达在膀胱移行细胞癌的发生、发展过程中起重要作用。二者同时检测有助于判断预后。     

NA:YAG激光虹膜切除术治疗闭角型青光眼201例临床观察

目的评价NA：YAG激光虹膜切除术治疗原发性闭角型青光眼和葡萄膜炎继发青光眼的临床疗效。方法回顾分析192例219眼原发性闭角型青光眼和9例葡萄膜炎继发青光眼，接受NA：YAG激光虹膜切除术后的临床效果，随诊16—46月。结果激光切孔一次成功205眼（占89e），激光能量在11—17．1mJ，67％病例在22—84Mj，击射次数2-33次。葡萄膜炎继发青光眼9眼均二次激光后虹膜孔通畅。95．61％术后眼压正常，视野无变化，术后早期一过性眼压升高占34％，术中出血占36％，房角色素增加占47％，1例术后28月接受小量切除术，8例术后需配合使用降眼压药物控制眼压。结论NA：YAG激光虹膜切除术是一种治疗闭角型青光眼的安全有效的方法。术前掌握适应症，把握手术时机，充分的术前准备是手术成功的关键。     

肾移植术后并发尿路上皮肿瘤的临床分析

目的 分析肾移植患者并发尿路上皮肿瘤的特点，探讨其诊治方法。方法 自1998～2003年肾移植患者1293例，术后发生尿路上皮恶性肿瘤21例（1．6％）。男4例，女17例。17例原发病为慢性问质性肾炎。发生尿路上皮肿瘤距肾移植6～62个月，平均26个月。其中膀胱癌6例，单侧肾盂或输尿管癌6例，单侧肾盂或输尿管、膀胱癌8例，双侧肾盂输尿管癌1例。10例上尿路肿瘤发生部位与移植肾同侧，4例发生于移植肾对侧。临床症状以无痛性肉服血尿和反复泌尿系感染为主。19例行手术治疗，术后所有患者免疫抑制剂用量减少1／3并辅以局部灌注化疗。结果 2例行姑息性治疗的晚期肿瘤患者分别于发现肿瘤5、8个月死亡。余19例现已随访2～5年。13例肿瘤复发，复发部位为膀胱或对侧原。肾、输尿管。所有患者在免疫抑制剂减量期间均未出现急性排斥。2例因切除移植肾恢复透析，17例肾功能正常。结论 慢性间质性。肾炎导致。肾功能衰竭的。肾移植患者和女性肾移植患者易发生移植后尿路上皮肿瘤；移植肾同侧上尿路较对侧好发肿瘤；对移植肾对侧为首发的上尿路发生肿瘤者可预防性行双侧上尿路根治性切除。     

Academic Degrees and Clinical Practice Characteristics: The University of Washington Physician Assistant Program: 1969-2000

CONTEXT: The physician assistant profession has been moving toward requiring master's degrees for new practitioners, but some argue this could change the face of the discipline. PURPOSE: To see if there is an association between physician assistants' academic degrees and practice in primary care, in rural areas, and with the medically underserved. METHODS: Surveys were sent to 880 graduates of the first 32 University of Washington physician assistant classes through 2000. Respondents noted their academic degree at program entry and the highest degree attained at any time up to the time of survey. Relationships between practice characteristics and academic degree levels were tested by unadjusted odds ratios and logistic regression after controlling for year of graduation and sex. RESULTS: Of the 478 respondents, 54% worked in primary care, about 30% practiced in nonmetropolitan communities, and 42% reported providing care for the medically underserved. Respondents with no degree (33% of total at entry, 24% at survey) were significantly more likely than degree holders to work in primary care and nonmetropolitan areas. Respondents with no degree at program entry were significantly more likely, and those with no degree at the time of the survey were marginally more likely, to self-report work with the medically underserved. CONCLUSION: Respondents with no academic degree are significantly more likely to demonstrate a commitment to primary, rural, and underserved health care. These findings may inform the national debate about the impact of required advanced degrees on the practice patterns of nonphysician providers.