We studied the influences of chronic tobacco exposure on aging and oxidant-antioxidant balance in two different strains of mice, hitherto called SAM (senescence-accelerated mice). One is a senescence-prone strain, "SAM-P/2," and another is a senescence-resistant strain, "SAM-R/1." We used 100 male mice--20 young (12 weeks of age) mice and 30 mature (24 weeks of age) mice from each strain. Half of each series were housed in a Hamburg II machine and exposed to tobacco smoke inhalation for five weeks. The result was that fewer of the mature SAM-P/2 survived compared with the mature SAM-R/1 after chronic tobacco inhalation. The grading of senility in the mature SAM-P/2 was also significantly higher than that in the mature SAM-R/1. The reduction of glutathione contents of blood and liver after tobacco exposure in the mature SAM-P/2 was greater than that in the young SAM-P/2 and the mature SAM-R/1. Moreover, oxygen radical generation of total blood cells stimulated by phorbol-myristate-acetate or opsonized zymosan showed a greater increase in the mature SAM-P/2 compared to the young SAM-P/2 and the mature SAM-R/1. These results indicate that the senescence-prone strain (SAM-P/2) was more susceptible to tobacco smoke exposure than the resistant strain (SAM-R/1). The impaired oxidant-antioxidant balance in the SAM-P/2 may therefore contribute to the process of senescence acceleration.

Aging↗

PubMedDate not supplied

Influences of cisplatin combination chemotherapy on oxygen radical generation by blood in elderly and adult patients with lung cancer.

Oxygen radical generation by blood cells before and after chemotherapy was investigated in 16 elderly (72.8 +/- 1.0 years) and 14 adult (45.0 +/- 2.4 years) patients with lung cancer, using a lucigenin-dependent chemiluminescence method. The oxygen radical generation by 100 microliters of blood before chemotherapy in the elderly and the adults was 3,784 +/- 123 and 3,969 +/- 125 chemiluminescence (CL), respectively. The value decreased gradually and reached a nadir at 2 weeks after therapy (elderly: 1,090 +/- 37; adult: 1,114 +/- 38 CL). Peripheral leukocyte counts also reached a nadir then: 1,308 +/- 140 and 1,288 +/- 44/mm3, respectively. However, the oxygen-radical-generating activity per leukocyte was not different before and after the therapy (elderly: 0.94 +/- 0.14 CL before to 0.83 +/- 0.09 CL after; adult: 0.97 +/- 0.13 CL before to 0.87 +/- 0.10 CL after). These results indicate that a decrease in oxygen radical generation by blood following chemotherapy is mainly due to a decrease in the number of polymorphonuclear neutrophils both in elderly and adult patients.

Adenocarcinoma↗

PubMedDate not supplied

Influences of tobacco smoke and vitamin E depletion on the distal lung of weanling rats.

Tobacco smoke is associated with pulmonary emphysema via elastase-antielastase and oxidant-antioxidant imbalance. This study addressed the tobacco smoke-induced changes in the lungs of weanling rats with vitamin E depletion. Three-week-old Wistar rats fed on vitamin E-depleted or normal diet were intermittently exposed to tobacco smoke by Hamburg II machines for 4 weeks. Tobacco smoke significantly suppressed body weight increases, particularly in the vitamin E-depleted group. In the normal diet group, tobacco smoke induced emphysematous changes with significant increases in the mean linear intercept (Lm) and the destructive index (DI), which was supported by an increase in elastase-like activity and a decrease in elastase inhibitory capacity (EIC) in bronchoalveolar lavage (BAL) fluid. Vitamin E depletion alone altered neither Lm nor DI. In tobacco-exposed animals in addition to vitamin E depletion, elastase-like activity, EIC in BAL fluid and DI were comparable to that in tobacco-exposed animals on a normal diet. However, Lm was markedly decreased with thickened epithelium and shrunk alveolar space. These results suggest that vitamin E depletion, when linked to tobacco exposure, might induce impaired lung development in the weanling rats, which is different from the emphysematous changes.

Animals↗

PubMedDate not supplied

[Analysis of nocturnal disturbed breathing in the elderly using desaturation index].

This study was conducted to examine the nocturnal ventilatory parameters and gas exchange in the elderly with nocturnal disturbed breathing. In order to facilitate analysis of ventilatory parameters with minimum manpower, we developed an unattended continuous nocturnal monitoring system for ventilation and arterial oxygen saturation. Using this system, nocturnal ventilatory parameters and gas exchange were investigated in our geriatric ward. We investigated 30 elderly subjects aged between 65 and 94 (mean age 77.8 +/- 6.5 years, male; female = 15:15). The subjects were free of severe cardiovascular and cerebrovascular disorders, and underwent 10 hours of continuous monitoring of ventilation and arterial oxygen saturation (SaO2). Number of significant desaturation (SDS; desaturation greater than 4% in SaO2 from the baseline value) and desaturation index (DI; sigma SDS(%) x duration (hour)) were calculated using the same system. The number of apnea episodes significantly correlated with DI and the number of SDS. DI also significantly correlated with lowest SaO2, while the number of SDS and the number of apneas were not found to be correlated with lowest SaO2. The number of SDS and the number of apnea episodes did not correlated with lowest SaO2. From the view point of gas exchange during the night, newly introduced DI is more comprehensive parameter when compared with the number of apneas or SDS. Subjects with a DI of over 0.5 were assigned to the group A (n = 8, mean age = 77.8) and the remaining subjects were assigned to group B (n = 22, mean age = 77.8). We compared the group A with the group B regarding nocturnal ventilatory parameters and SaO2.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗