Differential effects of vascular endothelial growth factor A isoforms in a mouse brain metastasis model of human melanoma

We reported previously that vascular endothelial growth factor isoform A (VEGF-A) expression by Mel57 human melanoma cells led to tumor progression in a murine brain metastasis model in an angiogenesis-independent fashion by dilation of co-opted, pre-existing vessels and concomitant enhanced blood supply (B. Kusters et al., Cancer Res., 62: 341-345, 2002). Here, we compare the activities of the 121, 165, and 189 VEGF-A isoforms in this model by transfecting Mel57 cells with the respective cDNAs and by injecting the resulting stably transfected cell lines in the internal carotid arteries of nude mice (n = 10 for each isoform). Although the three isoforms had similar potency to induce endothelial cell proliferation, VEGF(121) expression did not result in sprouting angiogenesis but rather led to extensive vasodilation and increased permeability of pre-existing, predominantly peritumoral vessels. Sometimes, proliferating endothelial cells accumulated in vessel lumina, giving these a microvascular, glomeruloid, proliferation-like appearance. Expression of VEGF(165) or VEGF(189) was associated with induction of an intratumoral neovascular bed. In VEGF(165)-expressing tumors, daughter endothelial cells were distributed among newly formed vessels that were extensively dilated. This also occurred in VEGF(189) tumors, but there, vasodilation was less pronounced. Using contrast-enhanced magnetic resonance imaging, the different vascular phenotypes were visualized on characteristic radiological images. VEGF(165) expression was the most unfavorable of the three. Mice carrying VEGF(165) tumors became moribund earlier than those carrying VEGF(121)-expressing tumors (16 +/- 4 days versus 22 +/- 3 days). Our data demonstrate that VEGF-A isoforms differ in angiogenic properties that can be visualized by contrast-enhanced magnetic resonance imaging.     

On the effect of biochemotherapy in metastatic malignant melanoma: an immunopathological evaluation

Although immunotherapy and biochemotherapy have shown promise, producing a subset of durable responses, for the majority of patients with metastatic melanoma the prognosis is still poor. Therefore there is a great need for predictive tests to identify patients with a high probability of responding. Furthermore, there is also a need for a better understanding of the mechanisms of action during treatment in order to be able to monitor the relevant antitumour reactivity during treatment and to optimize the efficacy of future immunotherapy and biochemotherapy. In the present study histopathological regression criteria were used to study the efficacy of biochemotherapy. Thirty-two patients with metastatic malignant melanoma (18 with regional disease and 14 with systemic disease) were treated with biochemotherapy (cisplatin 30 mg/m2 intravenously on days 1-3, dacarbazine 250 mg/m2 intravenously on days 1-3 and interferon-alpha2b 10 million IU subcutaneously 3 days a week, every 28 days). Pre-treatment fine needle aspirates were obtained from metastases to analyse the number of tumour-infiltrating CD4+ lymphocytes. Therapeutic efficacy was evaluated in metastases resected after treatment using histopathological criteria of tumour regression. Comparisons were also made with metastases from 17 untreated patients, all with regional disease. Regressive changes of 25% or more (of the section area) were found in two of the 17 untreated patients with regional disease compared with 13 of the 18 patients with regional disease and 10 of the 14 patients with systemic disease after biochemotherapy. Fifty per cent of the patients with regional disease showed a high degree of regressive changes (75-100% of the section area) after biochemotherapy. These results demonstrate the occurrence of an antitumour reactivity in the majority of patients. Patients with extensive regressive changes in 75-100% of the analysed biopsies were also found to have a longer overall survival (P = 0.019). In patients with regional disease there was a close correlation between a larger number of CD4+ lymphocytes pre-treatment and a higher degree of regressive changes post-treatment (P < 0.05). Thus, immunohistochemical analysis of tumour biopsies shortly after treatment seems to be a good surrogate endpoint. This technique also allows detailed analysis of antitumour reactivity and escape mechanisms.     

Effectiveness of sirolimus-eluting stent for treatment of left main coronary artery disease

The present study reports on the clinical outcome of 31 consecutive patients with left main coronary artery disease treated with a sirolimus-eluting stent. The implantation of this stent was associated with abolition of post-discharge fatal events and percutaneous reintervention.     

In vivo activities of mutants of vascular endothelial growth factor (VEGF) with differential in vitro activities

VEGF mutants in which Cys51 or Cys60 are converted into a serine are poor inducers of proliferation in human umbilical vein endothelial cells, but they have wild-type activity in the Miles vascular permeability assay. To assess the contribution of proliferation vs. other VEGF activities such as vascular permeability, to tumor angiogenesis and growth, C127I cells, transfected with BPV-based expression plasmids carrying wild-type or mutated VEGF cDNAs, were injected subcutaneously in BALB/c nu/nu mice. From C127I cells expressing wtVEGF(165), intensely vascularized and invasive tumors developed within 2 to 3 weeks. From cells expressing VEGF-Cys51Ser or VEGF-Cys60Ser, tumors developed only after 2 to 3 months, comparable to the time of development of control tumors, i.e., tumors from cells transfected with empty vector. Despite the late take, the VEGF-Cys51Ser and VEGF-Cys60Ser tumors developed an extensive vascular bed with an architecture comparable to that of recombinant wtVEGF-producing tumors whereas control tumors had a considerably lower vascular density. No metastases were detected in mice carrying either wtVEGF or mutant VEGF expressing tumors. Thus, because proliferation-defective VEGF-mutants cannot induce angiogenesis, we conclude that the proliferation-inducing effect of VEGF is crucial for tumor angiogenesis and growth. The hypervasculature in the tumors expressing these VEGF-mutants suggests, however, that other VEGF-activities, such as the induction of vascular permeability, strongly affects vascular density and vascular structure. Furthermore, neither overexpression of VEGF or a high vascular density or hyperpermeability of tumor vasculature is necessarily followed by metastasis.     

Contractile speed and fatigue of adductor pollicis muscle in multiple sclerosis

The purpose of the study was to investigate differences in contractile speed, force, and fatigability of the adductor pollicis muscle between 12 patients with multiple sclerosis (MS) and 8 sedentary control subjects matched for age and gender. There were no differences between the patients with MS and control subjects with respect to the percentage of maximal muscle force that could be recruited during voluntary effort (95.5 +/- 3.9% and 98.2 +/- 2.0%, respectively, P = 0.10), the stimulation frequency/force and force/velocity relationships, the rates of force development and relaxation, fatigue resistance, and the recovery rate of adductor pollicis muscle. However, previous results from the same group of MS patients showed that quadriceps femoris muscle force and resistance to fatigue were reduced. Therefore, our data support the clinical experience that, in patients with MS, lower limb muscle function is more or earlier affected than upper limb muscle function.     

刑事警察心理健康调查分析

①目的了解刑事警察的心理健康状况，为心理干预提供依据。②方法对济宁市刑警队员进行症状自评量表（Symptom Checklist 90．SCL-90）、焦虑自评量表（Self—rating Anxiety state，SAS）、抑郁自评量表（Self—rating Depression scale，SDS）评定。③结果济宁市刑警队员的SCL-90、SAS、SDS量表评分与全国常模相比存在显著性差异。④结论。刑事警察职业是一种特殊职业，该职业对队员的心理健康有显著的影响，这种影响随着从事刑警工作时间的不同而改变。     

黄芪注射液对肝纤维化大鼠模型肝细胞胶原及TGF-β_1表达的影响

目的探讨黄芪注射液抗肝纤维化及对TGF-β1、Col-Ⅰ表达的影响。方法将35只SD大鼠随机分为正常对照组、CCl4诱导肝纤维化模型组和黄芪干预组。至造模第10周,处死所有大鼠,采用PV免疫组化方法检测Col-Ⅰ在各组肝组织中的表达,ELISA法检测TGF-β1在各组血清中的表达。结果经CCl4诱导成功建立大鼠肝纤维化模型,随着肝纤维化程度的进展,肝组织中Col-Ⅰ和血清中TGF-β1表达明显增强。在正常对照组、黄芪干预组和肝纤维化模型组肝组织中Col-Ⅰ表达的平均光密度值分别为0.298、0.315、0.503,模型组与前两组比较差异均有显著性（P〈0.01）,而黄芪干预组与正常组肝组织比较差异无统计学意义（P〉0.05）。在正常对照组、黄芪干预组和肝纤维化模型组大鼠血清中TGF-β1表达含量分别为491.29pg/L、629.91pg/L、959.09pg/L,呈递增趋势。模型组与前两组比较差异均有显著性（P〈0.01）,黄芪干预组与正常组比较其表达含量无显著差异（P〉0.05）。结论黄芪注射液可以显著抑制实验性肝纤维化大鼠模型的肝纤维化,这种抑制作用可能与抑制I型胶原蛋白及TGF-β1的表达有关。