Induction of tumour necrosis factor-α by single and repeated doses of the antitumour agent 5,6-dimethylxanthenone-4-acetic acid

5,6-Dimethylxanthenone-4-acetic acid (DMXAA), a low-molecular-weight biological response modifier scheduled for clinical evaluation, induced synthesis of tumour necrosis factor- (TNF-) in serum of mice, with maximal activity being observed at 2–3 h after administration. At a dose of 27.5 mg/kg, DMXAA induced similar TNF- concentrations as did flavone-8-acetic acid given at its maximum tolerated dose (MTD; 330 mg/kg), whereas 8-methylxanthenone-4-acetic acid, which has no antitumour activity, did not induce serum TNF- at its MTD (440 mg/kg). The dependence of schedule on TNF- induction was studied by giving DMXAA to mice in two doses of 27.5 mg/kg each separated by different intervals. An interval of 0 (i.e 55 mg/kg given in a single dose) produced a TNF- concentration 9-fold that produced hy a single dose of 27.5 mg/kg. This dose, although higher than the MTD of 30 mg/kg, did not affect the health of mice at the time of assay (3 h). An interval of 1 day produced very low levels of serum TNF- after the second injection. An interval of 3 days produced high levels of serum TNF- after the second injection (9-fold that detected in mice receiving 27.5 mg/kg in a single dose) but no long-term toxicity, whereas an interval of 7 days produced an intermediate response. Thus, the first dose can either potentiate or suppress the TNF- response to a second dose. Mice with advanced subcutaneous colon 38 tumours were treated either with a single dose of DMXAA (27.5 mg/kg) or with a divided dose (two doses of 27.5 mg/kg given 3 days apart). Both the cure rate and the tumour-growth delay were enhanced by the divided-dose schedule. The results are relevant to the design of clinical administration schedules of DMXAA and emphasise the importance of TNF- induction in the antitumour response.This study was supported by the Auckland Division of the Cancer Society of New Zealand and by the Health Research Council of New Zealand     

Hard tissue laser ablation mechanisms

The aim of this work is the experimental and theoretical investigation of the influence of variable laser parameters (wavelength, fluence, pulse repetition rate) and of the optical and thermophysical properties of bone tissue (absorption coefficient, tissue inhomogeneity) as well as of the sample thickness on ablation thresholds and ablation rate. Ablation and perforation experiments were conducted using a semiconductively pre-ionized transverse excitation atmospheric pressure (TEA) carbon dioxide (CO₂) laser (10.6m and a sliding discharge TEA [hydrogen fluoride (HF)] laser (2.9m). The experimental data are discussed with respect to the following ablation mechanisms: thermal melting and vaporization process, pressure oscillation of gases released by the thermal decomposition of collagen and/or apatite, stresses due to the expansion of superheated water.     

Local interferon therapy for lip carcinoma

In a prospective non-randomized study 21 patients with lower lip squamous cell carcinoma were treated with human natural leukocyte interferon (HNLI). The response rate was measured by a size reduction of more than 25% and was 81%. A complete response rate was considered to be a cure according to histopathological and clinical findings and was 48%. The response rate of six lower lip squamous cell carcinoma cases treated with recombinant interferon alpha 2c was 67% and the complete response rate was 17%. Three patients with basal cell carcinoma of the upper lip were also treated with HNLI. All three patients were cured, as determined by histopathological and clinical findings. These findings indicate that interferon can be a useful alternative therapy for lip carcinoma either with or without surgery.     

手术前后补硒对结直肠癌患者免疫功能的影响

目的　研究手术前后服用酵母硒对结直肠癌患者免疫功能的作用。方法　1998 年3 月～1999 年3月,将我院的40 例大肠癌患者,随机分成对照组和治疗组,分别给予一般酵母和酵母硒(600μg/d) 持续2 周,观察治疗前后血硒水平、T 细胞亚群和免疫球蛋白,以及细胞因子αTNF 的变化。结果　补硒后,血硒由0 .79 ±0 .17μmol/L上升到0 .99 ±0 .23μmol/L,P< 0 .05 ;CD4 由24 .09 ±4 .10 % 上升到27 .95 ±4 .91 % ,CD8 由20 .18 ±2 .48 % 上升到23 .09 ±4 .47 % ,P< 0 .05 ;血清中Ig M 从83 .7 ±22 .37mg % 上升到103 .69 ±35 .49mg % ,P< 0 .05 。结论　手术前后给大肠癌患者服用酵母硒可明显地提高其血硒水平,改善机体的免疫功能并增强抗肿瘤的能力。     

P^16基因蛋白在子宫颈鳞癌组织中的表达

应用免疫组织化学方法对58例子宫颈鳞状上皮细胞癌及5例宫颈上皮内瘤样病变标本的P^16基因表达进行研究,取8例正常子宫颈组织作对照,结果显示：P16基因的阳性表达率在宫颈鳞癌,宫颈上此内瘤样病谱及正常宫颈组织中分别为43．1％,40％,12．5％,肿瘤病理分级越低,临床分期越晚,阳性表达率越低,差异有显著性（P＜0．05）,提示：P16基因的异常表达在子宫颈鳞癌的发生,发展过程中起重要作用。     

筋膜内子宫切除术86例临床分析

目的：报告筋膜内子宫全切术的方法及优点。方法：统计分析８６例筋膜内子宫全切与同期８０例子宫全切两组病人手术时间、术中出血、术后性功能、阴道脱垂情况进行对照。结果：筋膜内子宫全切术的手术时间及术中出血量均较子宫全切术明显减少,前者由于保留了宫颈外口及阴道的完整性,术后无１例阴道脱垂且性生活影响较小,结论：提倡对每例患者行子宫切除宫颈去留都应权衡利弊,以提高手术满意度和术后生活质量。     

P53与ras癌基因产物对直肠癌的诊断价值

目的提高直肠癌术前活检的诊断率。方法5年来手术治疗的168例直肠癌病人中,有20例（11．9％）第一次手术前活检不能明确诊断。对其中17例患者的活检组织石蜡标本（实验组）和10例正常肠粘膜活检标本（对照组）进行常规病理、P53与ras癌基因产物检测。结果实验组中P53与ras基因表达阳性率分别为71％与47％,阳性率均高于常规病理,有显著性差异。17例标本中,11例为不典型增生,5例仅有慢性炎症。不典型增生的P53与ras基因表达分别为11例和7例,而慢性炎症则全部为阴性。二者之间,两种基因表达阳性率均有显著差异。实验结果还显示P53与ras基因表达有较好的一致性。对照组的10例正常肠粘膜的活检标本P53与ras基因检测结果均阴性,与实验组比较,P53阳性率有显著差异。结论P53与ras基因表达检测,可以作为常规病理的补充,提高直肠良恶性病变的鉴别力。     

Trends in oral cancer mortality in Japan: 1950-1993

OBJECTIVES: To investigate trends in mortality rates of oral cancer patients in Japan between 1950 and 1993 by sex, age and cancer site, and compare the results with previous studies to determine whether there are any common characteristics of oral cancer patterns between Japan and European countries. MATERIAL AND METHODS: The mortality data obtained from the Japanese Vital Statistics were analyzed using the 5-year moving average method, and the mortality rates were adjusted to the 1990 world population by age and sex. Age-specific mortality rates were analyzed by birth cohort. RESULTS: The age-standardized mortality rates among the males increased from 1.14 per 100,000 person--years in 1952 to 1.84 in 1991, whereas the corresponding rate among females changed little over the same period. Cancer of the tongue was the most common cause of death in Japan among the five studied oral regions: lip, tongue, floor of the mouth, major salivary glands and oropharynx, males aged under 54 born in 1920 or later were found to have an increased risk of such disease. CONCLUSION: Further epidemiological investigations are necessary to clarify the etiology of oral cancer in Japan.     

心脏介入治疗院内感染的调查分析

目的：对我科心脏介入治疗后的院内感染发生率及易感因素进行回顾性调查分析,并探讨其防治措施。　方法： 我科自１９７３～１９９９年６ 月共收治行心脏介入治疗患者１ １００ 例,按照年龄、性别、手术种类、院内感染发生率及感染部位等资料进行比较分析。　结果：１ １００ 例患者中,术后感染２７例,感染率为２．４５％ 。包括经皮二尖瓣球囊成形术（ＰＢＭＶ）３８０ 例,感染２１ 例,感染率为５．５３％ ;永久性心脏起搏器安置术５２０ 例,感染６ 例,感染率为１．１５％ ;射频消融术２００ 例,无感染发生。最常见的感染为血管相关性感染和切口感染。感染发生与性别无显著相关性。　结论： 心脏介入治疗后院内感染发生率较低,通过严格的无菌操作和抗生素的合理应用,可防止院内感染的发生。     

右侧房室旁道的射频消融治疗

目的：报道２０例右侧房室折返性心动过速（ＡＶＲＴ）的射频消融疗效和体会。　方法：２０例ＡＶＲＴ患者,其中显性右侧旁路１５例,隐匿性右侧旁路５ 例,均给予射频消融治疗。　结果：１５ 例右侧显性旁道１３例消融成功,其中复发１例,再次消融成功;５ 例隐匿性旁路全部消融成功,消融成功率为９０％ ,无并发症。　结论：射频消融是一种治疗右侧ＡＶＲＴ安全而有效的方法。