丹酚酸A对大鼠半乳糖性白内障形成的抑制作用

业已证明,丹酚酸A有较强的抗氧化和清除自由基等多方面的作用。本实验用大鼠半乳糖性白内障模型,研究局部应用丹酚酸A对白内障形成的影响。结果表明,局部用0.05%的丹酚酸A(每日滴眼两次)对白内障的形成有一定的抑制作用,使白内障形成过程减缓。而且给药组动物晶体内过氧化氢和脂质过氧化产物(MDA)含量减少,蛋白巯基和总巯基增加。体外实验表明,丹酚酸A对醛糖还原酶有一定抑制作用。以上结果提示,丹酚酸A可通过不同途径抑制白内障的形成,对糖性白内障的防治有一定意义。     

Complicated pancreatic abscesses: problems in interventional management

Twenty-five patients with grade D or E pancreatitis underwent percutaneous drainage. These patients required multiple computed tomography (CT) examinations, multiple catheter insertions, multiple catheter manipulations, and long-term catheter drainage. Eight of the 25 patients were successfully treated with catheter drainage alone. Sixteen underwent surgical drainage, ten after attempts at percutaneous drainage and six prior to radiologic drainage. Of the ten patients who had initial percutaneous drainage, only four were clinically improved from the drainage procedure alone. Although the fluid component of the abscess was often adequately drained in all ten patients, surgery was required to remove pieces of necrotic debris. Six patients who underwent surgical debridement had residual abscesses in the post-operative period and were all successfully treated with percutaneous drainage. One patient died from unrelated causes. Successful interventional management of patients with pancreatic abscesses requires intensive radiologic intervention and monitoring and may be better served by a combination of radiologic and surgical means.     

Superparamagnetic iron oxide: enhanced detection of focal splenic tumors with MR imaging

Superparamagnetic iron oxide (AMI-25), a reticuloendothelial cell-specific contrast agent for magnetic resonance (MR) imaging, was evaluated for its ability to permit detection of splenic metastases in 18 patients. Superparamagnetic iron oxide, at a dose of 30 mumol of iron per kilogram, decreased the signal intensity of spleen from 19.5 +/- 4.8 to 3.1 +/- 2.2 (spin-echo sequence, repetition time msec/echo time msec = 1,500/42; P less than .05), without changing the signal intensity of tumor. As a result, the tumor-spleen contrast-to-noise ratio increased from 0.2 (tumor isointense relative to spleen) to 18.0 (tumor hyperintense relative to spleen). As a consequence of increased contrast, splenic tumors were detected in four of 18 patients (45 individual lesions; P less than .05), whereas nonenhanced MR imaging permitted detection of splenic lesions in only two of 18 patients (four individual lesions). Maximum tumor-spleen contrast was achieved within 60 minutes after intravenous administration. These initial clinical results indicate that MR imaging with superparamagnetic iron oxide may offer improved accuracy in the diagnosis of splenic tumors.     

Topoisomerase II beta expression level correlates with doxorubicin-induced apoptosis in peripheral blood cells

Anthracyclines are widely used in oncology. Both the response and side-effects of anthracyclines are individually variable, but determinants or predictive markers of this variability are not available. We investigated the variability in the expression of the anthracycline targets topoisomerases II (topo II) alpha and beta and its significance for the apoptotic response following exposure to the anthracycline doxorubicin. Only topo II beta protein expression was detected in peripheral blood cells. Usually considered a constitutively expressed protein, topo II beta varied 3-, 18-, and 16-fold on the mRNA, protein and activity levels, respectively, among the volunteers tested. In addition, the expression of topo II beta was modified by several mitogens, suggesting a role in the regulation of cell cycle. Strikingly, topo II beta activity correlated statistically significantly with the apoptotic response in peripheral blood leukocytes exposed to 1 μM doxorubicin. A longitudinal study in a subset of study subjects demonstrated that 30% of the topo II expression variability may be inherited. However, resequencing of the TOP2B gene in 48 unrelated individuals revealed only 8 gene variants, none of them with obvious effects on the expression or protein sequence of topo II beta. Taken together, the apoptotic response to doxorubicin in peripheral blood cells may be mediated by topo II beta. The expression level of topo II beta is intra- and inter-individually variable, and may in part determine the apoptotic response to doxorubicin and other anthracyclines.     

A projection of the impact of lipid-lowering therapy on high-risk employee disability and medical costs

OBJECTIVE: The objective of this study was to examine the impact of introducing rosuvastatin calcium on direct and indirect costs among patients at high risk for coronary heart disease. METHODS: An economic simulation model was developed to project the number of cardiovascular events and associated direct and indirect costs under varying treatment scenarios. RESULTS: In an average-sized commercial health plan with 210,000 covered lives and 9,336 high-risk patients, an uptake of rosuvastatin by 11% of high-risk patients would result in eight fewer cardiovascular events, a net savings of 0.85 million dollars in direct medical costs and a net savings of 36,404 dollars in productivity loss over a period of 5 years. The overall reduction in total costs is equivalent to 1735 dollars per rosuvastatin-treated patient. CONCLUSIONS: At current statin prices, the use of rosuvastatin could lead to fewer cardiovascular events and lower direct and indirect costs.