Ten patients with lung cancer and mediastinal tumor invading the mediastinal structures underwent replacement of superior vena cava (SVC) with ringed Gore-Tex to resect malignant tumors. In patients with lung cancer sleeve pneumonectomy (3 patients), sleeve lobectomy (1 patients) and tracheal resection (one patient) were performed simultaneously. By resection of the VCS system, invasive thymomas were able to be resected completely in 2 of 3 patients. In 2 patients with mediastinal tumors, one with metastatic testicular chorio carcinoma and one with malignant lymphoma of non-Hodgkin type, aggressive chemotherapy was followed by resection of the residual tumors including VCS. Except for one patient, there was no sign showing disturbance of the venous return in the VCS system in the 5 to 43 months' postoperative follow up period. We conclude that ringed Gore-Tex graft permits the extended operation for intrathoracic malignancies invading the mediastinal structures.
To select a proper laser for arthroscopic laser meniscotomy, we studied the menisci ablation rate and damaged layer thickness made by various laser irradiations. The pig knee-joint menisci were used as sample materials. We use eight different lasers from UV region to IR region, pulsed or cw: ArF, KrF, XeCl, XeF excimer lasers, Ar+ UV, Ar+ visible, CO and CO2 lasers. We irradiated these lasers on menisci at an input power density of 60J/cm2/sec.The proper laser for the arthroscopic laser meniscotomy must indicate high ablation rate and thin damaged layer for menisci. Furthermore it can be delivered by flexible fibers. In this point of view, we concluded that the proper laser satisfying those requirements may be XeC1 excimer laser.
Results of epidemiological studies concerning the association between smoking and alcohol use and gallstone risk are inconsistent. We examined the relation of smoking and alcohol use to gallstone disease in Japanese men.We investigated 174 cases having gallstones as determined by ultrasonography, 104 cases of postcholecystectomy state, and 6,906 controls having a normal gallbladder in the consecutive series of 7,637 men aged 48-59 years receiving a retirement health examination at four hospitals of the Self-Defense Forces from 1986 to 1994. Fifty men had been aware of having gallstones. Known gallstones and postcholecystectomy state were combined as known gallstone disease. Smoking and drinking habits were ascertained by a self-administered questionnaire. Statistical adjustment was made for body mass index, glucose tolerance status, Self-Defense Forces rank, hospital, and either cigarette smoking or alcohol use.Cigarette smoking was not measurably associated with either prevalent gallstones or postcholecystectomy state, nor with either newly diagnosed gallstones or known gallstone disease. Alcohol use was related to a significant decrease in the prevalence odds of both gallstones and postcholecystectomy state, and the decrease was slightly more profound for known gallstone disease.Cigarette smoking is probably unrelated to the gallstone risk, and alcohol consumption seems to confer protection against gallstone formation.
Alcohol drinking as well as cigarette smoking has been associated with development of colorectal polyps. Asians such as Japanese, Chinese and Korean have high frequency of genetic polymorphism in low Km aldehyde dehydrogenase (ALDH2) gene which greatly regulates alcohol intake. In the present study, we investigated associations of this polymorphism and lifestyles with colorectal polyps in self-defense forces personnels in Japan. All subjects received colonoscopy at a retirement health examination. The ALDH2 genotype was determined using polymerase chain reaction and restriction fragment length polymorphism method. Frequency of the ALDH2 genotype was not different between those with colorectal polyps (n=69) and those without the polyps (n=131). Smoking was associated with development of colorectal polyps (OR=4.7, 95% confidence interval= 1.9-11.5) in the ALDH2 proficient genotype. The association appeared to be enhanced by drinking alcohol since a synergistic effect of smoking and alcohol drinking (>_60 ml/day) was indicated (OR=9.9, 95% confidence interval=2.9-34.1) by logistic regression analysis. In the ALDH2 deficient genotype, however, we could not evaluate interactions of smoking and alcohol drinking on colorectal polyp development because of the small sample size of heavy alcohol drinkers. The genotype analysis would be useful in evaluating effects of environmental factors on outcomes for each genetically defined subpopulation. J Epidemiol, 2000 ; 10 : 366-371
The laser ablation characteristics of the procine menisci by the various laser irradiations were studied. We employed nine laser wavelengthes from ultraviolet(UV) region to infrared(IR) region, pulsed or continuous wave(cw). They were ArF(193nm in wavelength, pulsed), KrF(248nm, pulsed), XeC1(308nm, pulsed), XeF(351nm, pulsed), Ar ion UV(351nm,cw), Ar ion visible(515nm, cw), Nd:YAG(1.06pm, cw), C0(5.3pm, cw) and C02(10.6jim, cw) lasers. All laser irradiation experiments were performed in vitro with a fixed laser beam to the menisci in air circumstance. The ablation rate and damaged layer thickness were measured. In order to compare the ablation characteristics of various laser wavelengths at the same condition, the laser irradiation energy density was kept constant to 60,J/cm2/sec. The ablation rate by the energy density of 1J/cm2 and the damaged layer thickness by the energy density of 1200J/cm2 were measured. The measured menisci ablation rate by ArF excimer laser was 9.5 (ArF 9.5), (KrF 92.1), (XeCl 74.4), (XeF 2.3), (Ar ion UV 64.8), (CO 69.5), (CO2 204.9) )ig/J. The damaged layer thickness of menisci by ArF excimer laser was 119 (ArF 119), (KrF 12), (XeCl 299), (XeF 645), (Ar ion UV 860), (CO 1105), (CO2 1209) pm. This study will investigate if the ablation characteristics depends on the wavelength of lasers and on emission mode (pulsed or cw). In the case of XeC1 excimer laser irradiation experiment, the contact irradiation to menisci in the water circumstance were carried out. The ablation rate using XeC1 excimer laser in water by the contact method was almost equal to that by the non-contact method in air. The damaged layer thickness using XeC1 excimer laser in water was considerably thin compared with that by the non-contact method in air. We expect that this study for menisci laser ablation may be contribute the progress in arthroscopic laser meniscectomy.
This case-control study examined the relationship between the occurrence of colonic polyps in men in their fifties and the level of their physical fitness while in their thirties. The subjects consisted of 51 male Japan Self-Defense Forces officials in their fifties who had colonic polyps, as diagnosed by colonoscopic examination, and 46 control individuals. As an indicator of physical fitness between 30 and 39, we selected the best time recorded for each individual during that decade of life for the 1,500 meter Physical Fitness Test run. We calculated the odds ratio for polyps according to selected risk factors (including physical fitness), and a logistic regression analysis was used to adjust for possible confounding variables. Odds ratio (95% confidence interval, p value) for colonic polyps with physical fitness in the thirties was 0.36 (0.16-0.82, p < 0.05). With adjustment for the subjects' maximum Body Mass Index in both their thirties and fifties, and serum total cholesterol, the odds ratio was 0.39 (0.15-0.99, p < 0.05). We suggest that the occurrence of colonic polyps in men in their fifties can be reduced by maintaining a high level of physical fitness while in their thirties.
