典型工业区周围土壤重金属污染评价及空间分布

以沈阳冶炼厂厂区及其周围土壤为对象,研究土壤重金属污染状况及其空间分布特征.结果表明,调查区域表层土壤(0-20 cm)中,Cd、Pb、Cu和Zn浓度范围分别在7.25-81.20,562.92-1014.10,289.70-527.93,673.36-1021.60 mg/kg,其平均含量分别为国家土壤质量二级标准(GB15618-1995)的74.92,2.27,4.07和3.15倍,污染程度呈现出Cd>Cu>Zn>Pb的特征.在空间分布方面,受人为与环境气象因子的共同影响,原沈阳冶炼厂厂区周围土壤中Cd、Pb、Cu、Zn 4种重金属污染带的空间分布特征呈西北至东南方向分布,西北方向土壤污染最为严重,东北至西南方向和正东至正西方向较轻.4种重金属中,Zn的污染范围最大,Cd污染在空间分布上主要集中于污染点源附近,Pb和Cu的空间分布介于Cd和Zn之间.     

Clinical and immunological effects of treatment with murine anti-CD3 monoclonal antibody along with interleukin 2 in patients with cancer

Anti-CD3 mAb and interleukin 2 (IL-2) were used in a Phase I study to treat 29 patients with cancer. The anti-CD3 was given as an i.v. bolus infusion over 10 min followed by two i.v. 96-h continuous infusions of IL-2 at 3 x 10(6) units/m2/day with a 3-day rest between the IL-2 infusions. Four patients were treated with 6, 18, 60, and 300 microgram/m2 anti-CD3. One patient received 3000 microgram/m2 anti-CD3. This patient developed profound hypotension and the IL-2 infusions were delayed for 2 weeks. Two patients were treated at an intermediate dose of 600 microgram/m2. These patients developed dose-limiting toxicities including hypotension, dyspnea and increased blood urea nitrogen, creatinine, and bilirubin. They were unable to complete their first course of therapy. In an effort to achieve a dose of anti-CD3 which would activate T cells in vivo, pentoxifylline was given to blunt the toxicities seen with anti-CD3 thought to be due predominantly to the cytokine syndrome and tumor necrosis factor release. Four patients received p.o. pentoxifylline to cover an anti-CD3 dose of 600 microgram/m2. The IL-2 infusion was initiated 1 week after the mAb. While there was an anti-CD3 dose-dependent increase in serum tumor necrosis factor level 1 h after mAb infusion, pentoxifylline did not reduce the serum tumor necrosis factor level. There was also an anti-CD3 dose-dependent increase in the serum soluble IL-2 receptor levels. Other immune parameters monitored, including in vitro cytotoxic and proliferative responses and lymphocyte count, were similar to treatment courses with IL-2 alone. Fourteen of 26 patients examined developed human anti-murine antibodies following a single dose of anti-CD3. There were no objective antitumor responses. We conclude that in vivo treatment with anti-CD3 did not enhance T cell activity or expansion with subsequent IL-2 infusion and that the combination of anti-CD3 followed by IL-2 did not improve upon the antitumor activity previously seen with IL-2 alone.     

Vascular endothelial growth factor expression is higher in differentiated thyroid cancer than in normal or benign thyroid

Vascular endothelial growth factor (VEGF) is an angiogenic factor, and its expression has been rarely demonstrated in thyroid tumors. We, therefore, investigated the expression of VEGF messenger RNA (mRNA) and production of VEGF protein in cell lines from human primary and metastatic follicular (FTC-133, FTC-236, and FTC-238), papillary (TPC-1), Hürthle cell (XTC-1), and medullary thyroid cancers (MTC-1.1 and MTC-2.2), and in human thyroid tissues (papillary, follicular, medullary, and Hürthle cell cancers, follicular adenomas, and Graves' thyroid tissue) by Northern blot, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) studies. All thyroid cell lines expressed a 4.2-kilobase VEGF mRNA. The VEGF mRNA levels were higher in the thyroid cancer cell lines than in primary cultures of normal thyroid cells, and higher in thyroid cancers of follicular than those of parafollicular cell origin. The VEGF mRNA levels were similar in primary and metastatic thyroid tumors. Immunohistochemical staining and Northern blot analysis of the cell lines correlated positively, thus thyroid cancer cell lines stained more intensely than normal thyroid cells and follicular tumor cells more intensely than parafollicular tumor cells. Again, no difference was noted in VEGF staining between primary and metastatic thyroid tumors. Deparafinized sections of papillary, follicular, and Hürthle cell cancers also stained much stronger than those of medullary thyroid cancers, benign, or hyperplastic (Graves' disease) thyroid tissue. Thyroid cancer cell lines (XTC-1 > TPC-1 > FTC-133 > MTC-1.1) also secreted more VEGF protein as measured by ELISA than did normal thyroid cells. VEGF secretion of cell lines derived from primary and metastatic thyroid tumors were similar. VEGF mRNA is therefore expressed, and VEGF protein is secreted by normal, hyperplastic, and neoplastic thyroid tissues. The higher levels of VEGF expression in differentiated thyroid cancers of follicular cell origin suggests a role in oncogenesis.     

First use of an untethered, vented electric left ventricular assist device for long-term support

This report describes the first long-term (505-day) application of the vented electric (VE) HeartMate left ventricular assist device (LVAD) (Thermo Cardiosystems, Inc). The device consists of an abdominally placed, battery-powered titanium blood pump that, in contrast to earlier pneumatically powered systems, allows patients untethered freedom of movement. The batteries last 5 to 8 hours and can be changed on a rotating basis indefinitely. The patient, a 33-year-old man (90 kg, blood type O) with idiopathic cardiomyopathy, experienced end-organ heart failure (New York Heart Association [NYHA] class IV) while he was awaiting heart transplantation. When his hemodynamic criteria met those outlined in the protocol, we implanted the VE-LVAD as a bridge to transplantation. The patient was supported by the device for more than 16 months. His cardiac status returned to NYHA class I, and he was eventually allowed to take day trips outside the hospital as he awaited transplantation. The VE-LVAD enabled the patient to participate in activities such as eating in restaurants, going to movies, and practicing basketball shots. Unfortunately, the patient died suddenly due to a neurological thromboembolic event that occurred on day 503 of VE-LVAD support. The VE-LVAD improved native left ventricular function by chronic unloading, and ventricular remodeling resulted in a more normal configuration anatomically, physiologically, and ultimately, histologically and pathologically.     

Striatal [18F]fluorodopa utilization after COMT inhibition with entacapone studied with PET in advanced Parkinson's disease

The effect of peripheral catechol-O-methyltransferase (COMT) inhibition with entacapone on striatal uptake of 6-[18F]fluoro-L-dopa (FDOPA) was studied with PET both without and with entacapone in fifteen advanced parkinsonian patients and six healthy controls. Entacapone significantly enhanced the fraction of unmetabolized FDOPA in plasma from 16% to about 50% at 80 minutes after FDOPA injection in all subjects. The striatal to occipital ratios and the striatal FDOPA uptake, expressed as a modified decarboxylation coefficient (k3R0), was significantly increased in healthy controls, whereas in parkinsonian patients the increase was significant only in the caudate. On the other hand, the influx constant (Ki) decreased significantly in the caudate and putamen in parkinsonian patients; in healthy controls the Ki remained virtually unchanged. Effective peripheral COMT inhibition markedly increased the fraction of FDOPA in plasma and thus its availability in the brain for decarboxylation both in patients and control subjects. However, the change in striatal FDOPA uptake was modest in the advanced parkinsonian patients as compared to that in control subjects, because of the advanced disease, decreased storage capacity, or both.     

Sex differences in the pharmacological treatment of hypertension: a review of population-based studies

OBJECTIVE: To summarize all available literature on sex differences in the pharmacological treatment of hypertension with respect to the percentage of hypertensive patients treated pharmacologically and the selection of antihypertensive drugs. The influences of the calendar period, age, definition of hypertension, prevalence of hypertension and country on these sex differences were examined. DATA IDENTIFICATION: A secondary analysis of data from 46 population-based studies in 22 countries on the prevalence of pharmacologically treated hypertension was conducted to estimate sex ratios for the prevalence of drug treatment for hypertension. RESULT: Overall, women with hypertension were 1.33-fold [95% confidence interval (CI) 1.32-1.34] more likely to be treated pharmacologically for hypertension than were hypertensive men. With increasing age, the female: male ratio for pharmacological treatment of hypertension decreased from 2.26 (95% CI 1.56-3.27) at ages 20-29 years to 1.22 (95% CI 1.11-1.34) at ages 60-69 years. In all countries more women than men were treated for hypertension, with the biggest difference observed in the USSR (1983-1986), where about twice as many women as men were treated for hypertension. Women more frequently used diuretics, whereas men more often used beta-blockers, angiotensin converting enzyme inhibitors and calcium antagonists. CONCLUSIONS: Hypertensive women are more often treated for hypertension than hypertensive men and their pattern of use of antihypertensive drugs differs from that of men. Further research is required in order to explain sex differences in the treatment of hypertension with respect to the prevalence of pharmacological treatment of hypertension and choice of antihypertensive drugs, and to investigate the consequences of this difference for long-term outcomes.     

Enhanced Inhibition of Listeria monocytogenes by Glycerol Monolaurate with Organic Acids

Glycerol monolaurate (ML) inhibition of Listeria monocytogenes was affected by pH and testing matrix. We investigated antimicrobial effects of ML combined with acetic, benzoic, citric, and lactic acids (AA, BA, CA, and LA) on L. monocytogenes in broth medium and crawfish tail meat. Minimum inhibitory concentrations were lower when ML was combined with each acid in dual combination. ML combined with sublethal amounts of AA, BA, or LA gave greater inhibition than for the most active compound alone. No interaction occurred between ML and CA. ML had no influence on pH of media containing organic acids. ML or LA in crawfish tail meat had reduced activity. ML activity was influenced by type of organic acid used. Combining ML with organic acids may provide similar protection to other precooked ready-to-eat foods.