2-甲酰(乙酰)取代喹啉缩氨基硫脲的合成

缩氨基硫脲类化合物有抗肿瘤、抗病毒和抗菌等多种药理活性。Barret等首次报道了乙二醛二缩氨基硫脲(Ⅰ)的抗疟活性。Klayman等研究了缩     

Das sinunasale undifferenzierte Karzinom

Sinonasal undifferentiated carcinoma (SNUC) is a rare tumor of the nasal cavity and paranasal sinuses first described in 1986. Olfactory neuroblastoma and SNUC may appear quite similar on histological examination. Due to the fact that olfactory neuroblastoma has a much better prognosis, a distinction with SNUC has to be drawn. We report a case of SNUC and describe the role of immunohistochemistry in making an accurate histological diagnosis. In addition, potential factors influencing the development of SNUC described in the literature and current treatment modalities are discussed. Despite aggressive and multimodal treatment regimens, the outcomes of patients suffering from SNUC have remained dismal. A randomized controlled clinical study could be the basis for determining the optimal treatment for SNUC.     

Brain metastases in patients under 50?years of age: retrospective analysis

Several previous publications suggested that younger patients with brain metastases have longer survival than older patients. However, detailed studies of younger patient groups are scarce. Therefore, a multi-institutional analysis of younger patients with brain metastases was performed (defined as adults with age <50?years). Prognostic factors for survival were examined by uni- and multivariate analyses and compared to those obtained in patients with age ??50?years. Multivariate analysis of 106 patients (median age 44?years, range 23?C49?years) revealed three independent prognostic factors for survival: performance status, extracranial metastases and primary tumor control. Survival was significantly better in patients treated after the year 2000 (median 9.4?months) as compared to those treated before the year 2000 (median 5.1?months, p?=?0.04). This improvement appeared to be related to an increased use of surgery or radiosurgery (SRS) and decreasing numbers of patients with uncontrolled primary tumor. Irrespective of management approach, survival beyond 5?years was uncommon (actuarial rate 6?%; 17?% in patients treated with upfront surgery or SRS). In conclusion, more intense multidisciplinary approaches aiming at control both in the brain, extracranial metastatic sites, and primary tumor site might have contributed to gradual survival improvements in recent years. Nevertheless, further efforts are necessary to improve long-term survival.     

Activated protein C decreases plasminogen activator-inhibitor activity in endothelial cell-conditioned medium

Confluent cultures of endothelial cells from human umbilical cord were used to study the effect of activated human protein C (APC) on the production of plasminogen activators, plasminogen activator-inhibitor, and factor VIII-related antigen. Addition of APC to the cells in a serum-free medium did not affect the production of tissue-type plasminogen activator (t-PA) or factor VIII-related antigen; under all measured conditions, no urokinase activity was found. However, less plasminogen activator-inhibitor activity accumulated in the conditioned medium in the presence of APC. This decrease was dose dependent and could be prevented by specific anti-protein C antibodies. No decrease was observed with the zymogen protein C or with diisopropylfluorophosphate-inactivated APC. APC also decreased the t-PA inhibitor activity in endothelial cell-conditioned medium in the absence of cells, which suggests that the effect of APC is at least partly due to a direct effect of APC on the plasminogen activator- inhibitor. High concentrations of thrombin-but not of factor Xa or IXa-- had a similar effect on the t-PA inhibitor activity. The effect of APC on the plasminogen activator-inhibitor provides a new mechanism by which APC may enhance fibrinolysis. The data suggest that activation of the coagulation system may lead to a secondary increase of the fibrinolytic activity by changing the balance between plasminogen activator(s) and its (their) fast-acting inhibitor.     

Grafting assay distinguishes promotion sensitive from promotion resistant JB6 cells

The JB6 mouse epidermal cell system has been used extensively as an in vitro transformation model for the study of tumor promotion. The standard JB6 cell assay for promotion of transformation is carried out in soft agar or other anchorage independent conditions. The present study was directed to the development of an in vivo model to distinguish the promotion resistant (P-) and promotion sensitive (P+) progression phenotypes. Results indicate that the grafting assay distinguishes P- and P+ cells in vivo with P+ but not P- cells forming tumors within 7-9 weeks. Expression of dominant negative mutant jun TAM67 blocks both anchorage independent transformation response and graft bed tumor formation by P+ cells, suggesting that the requirement for AP-1 activation in transformation now applies in vivo. Expression of mutated p53 produced a gain of P+ phenotype in P- cells in vitro, but not in vivo. Histochemical and Northern blot analysis for expression of various keratinocyte markers revealed no evidence for expression, suggesting a loss of keratinocyte markers following establishment in culture. In summary, the skin-grafting assay described in this study appears to be a valid in vivo assay for distinguishing the preneoplastic progression phenotypes represented by JB6 P- and P+ cells.      

Prevention of radiation-induced central nervous system toxicity: a role for amifostine?

PURPOSE: To review the role of amifostine (WR-2721) in ameliorating radiation-induced central nervous system (CNS) toxicity. MATERIALS AND METHODS: Literature review and presentation of preliminary animal experiments designed to test the efficacy of both intrathecal and subcutaneous application of amifostine. RESULTS: Despite its inability to cross the blood-brain barrier, amifostine appears promising because it protects blood vessels against radiation-induced damage. Vascular damage is one of the most important components in the development of CNS toxicity after radiotherapy. Furthermore, the increased permeability of the blood-brain barrier during fractionated radiotherapy might allow penetration of amifostine. Three animal studies with systemic administration found positive results after brain irradiation with different fractionation schedules, total doses and amifostine doses. One study where amifostine was given after radiotherapy showed no protection, suggesting that the timing of the drug application is crucial. Further data suggest that either intrathecal or systemic administration might protect the spinal cord as well. In our experience with spinal cord irradiation, systemic administration was more effective than intrathecal. Regarding CNS protection, the optimum dose of amifostine has yet to be determined. CONCLUSION: Several independent experiments provided preliminary evidence that modulation of the radiation response of the CNS in vivo by systemic administration of amifostine is possible and feasible. Additional studies are warranted to investigate the protective effect with differing regimens of administration, more clinically relevant fractionation regimens and longer follow-up.     

Epidermal growth factor receptor as a target to improve treatment of lung cancer

Despite considerable efforts to reduce tobacco use, lung cancer remains the most common cancer in both men and women. Recent advances in radiation therapy and chemotherapy for lung cancer have yielded encouraging results, but survival in patients with locally advanced non-small-cell lung cancer (NSCLC) remains poor. As more and more molecular changes and their importance in malignant tissues continue to be characterized, approaches to target those aberrant pathways are being actively explored. The epidermal growth factor receptor (EGFR) is commonly overexpressed in NSCLC, particularly squamous cell carcinoma, and has been implicated in the development and progression of this disease, although a clear correlation with prognosis has not been established. Several different strategies have been developed to target and block the EGFR and its downstream effects, and some of them have been intensively studied in preclinical and clinical studies as a single-agent approach or in combination with radiation therapy or chemotherapy. In this article, we review the role of EGFR in lung cancer, as well as preclinical and clinical data on strategies to interfere with EGFR signaling alone or in combination with chemotherapy, radiation, or both.     

Differential diagnosis of parapharyngeal mass

BACKGROUND: Parapharyngeal lesions are rare. Tumors arising in the parapharyngeal space can be silent clinically for a long period of time. Physical findings like dislocation of the pharyngeal walls or cervical swelling are often recognized by chance. MATERIAL AND METHODS: Representing three cases of parapharyngeal tumors the differential diagnosis of parapharyngeal masses and the importance of the magnetic resonance imaging will be shown. CONCLUSIONS: Mostly, parapharyngeal masses are represented by salivary gland tumors (40%-50%). The second most common tumors in the parapharyngeal space are neurogenic tumors (17%-25%). Paragangliomas are the third group of common parapharyngeal lesions (10%-15%). A mixed group of lesions like branchial cleft cysts, lymph nodes and hematogenic tumors represent the remaining part of the parapharyngeal masses (10%-33%). Most of the lesions (80%) are benign. Because of the magnetic response imaging a reliable preoperative diagnosis is possible in more than 80% of the tumors. The surgical management may also be influenced by the location of the tumor shown in the magnetic resonance imaging.