Effects of endurance training on resting and post-exercise cardiac autonomic control

PURPOSE: Endurance training induces reductions in both resting and postexercise heart rate (HR). If adaptation in cardiac autonomic regulation is a contributing factor in these reductions, changes in cardiac autonomic nervous system (ANS) should correspond to those in HR during an endurance-training program. We investigated the changes in resting and postexercise HR variabilities (both in the time and frequency domain) over a 6-wk training program. METHODS: HR variability was measured five times in an endurance-training group (N = 7) and four times in a control group (N = 5) during the course of study. RESULTS: Endurance training decreased HR and increased indices of parasympathetic modulation measured both at rest and during postexercise recovery periods. Noteworthy is that no changes in either HR or indices of ANS modulation measured during postexercise recovery periods were detectable after the first 7 d of the study despite continued changes in resting HR and indices in ANS modulation measured between the 7th and 42nd days of the endurance-training program. CONCLUSIONS: The study demonstrates that with endurance-training changes in cardiac ANS modulation partly contribute to a decrease in HR at rest and during postexercise recovery period, and that adaptation of the cardiac autonomic control occurs sooner in immediate postexercise periods than at rest.     

Diffusion tensor imaging in infants with basal ganglia-thalamic lesions.

We performed diffusion tensor imaging in two infants with neonatal hypoxic-ischemic encephalopathy. MRI revealed basal ganglia-thalamic lesions in both patients during the neonatal period. Patient 1 had severe neurological sequelae, whereas patient 2 achieved normal development. Conventional MRI at 12 months of age showed abnormal high-intensity areas in bilateral basal ganglia and thalami in patient 1, whereas no abnormal intensities were recognized in patient 2. Diffusion tensor tractography demonstrated poor depiction of white matter tracts above the level of centrum semiovale in patient 1. Region of interest analysis showed that fractional anisotropy of white matter of centrum semiovale and deep white matter was markedly reduced in patient 1 compared with patient 2, although apparent diffusion coefficient was not largely different between them. Our study suggested that abnormalities of diffusion property will be more widely present than those of conventional MRI. Diffusion tensor imaging will be useful to detect white matter abnormalities in normal-appearing white matter on conventional MRI.     

Risk of developing mesothelioma due to neighborhood exposure to asbestos]

Routes of asbestos exposure consist of occupational and non-occupational exposures, and furthermore the latter is classified as para-occupational, neighborhood or true general environmental exposure. Consequently, in order to evaluate health risk caused by neighborhood exposure to asbestos, it is necessary to exclude risk due to the other exposure routes from overall risk. We reviewed epidemiological studies on the relationship between neighborhood asbestos exposure and risk of mesothelioma. In studies on a crocidolite mine in South Africa and a chrysotile mine in Canada, occupational exposure was not excluded. In studies on a crocidolite mine in Australia and an asbestos manufacturing factory in U.S.A., risk caused by non-occupational exposure was evaluated, but the risk was not classified as para-occupational and neighborhood exposures. In a study on an asbestos cement factory in Italy, first, occupational and para-occupational exposures were excluded, and next, the incidence rate of mesothelioma in neighborhood residents was calculated, so that risk caused by neighborhood exposure could be evaluated. In case-control studies in Italy, South Africa, three European countries and the U.K., risks caused by occupational, para-occupational and neighborhood exposures were evaluated separately. As a whole, relative risk (RR) of neighborhood exposure in crocidolite and amosite mines was about 10 to 30 and RR in major asbestos factories was about 5 to 20. On the other hand, statistically significant RR of neighborhood exposure was not observed in chrysotile mines and some asbestos facilities.     

Carcinogenic risk of heterocyclic amines in combination – Assessment with a liver initiation model

Carcinogenic potential of heterocyclic amines (HCAs) was investigated using an in vivo 5-week initiation assay with quantitative evaluation of glutathione S-transferase placental form (GST-P) positive foci in rat liver. Numbers of GST-P positive foci were significantly increased with individual administration of six different HCAs, indicating utility of the assay. It was therefore applied to investigate risk with multiple HCAs in combination. Unexpectedly, concomitant treatment with 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) did not result in any additive carcinogenicity. In the rats taking MeIQx prior to PhIP the value was almost equal to the sum total of individual data, indicating additive initiation activities. In contrast, simultaneous or prior administration of PhIP rather exerted inhibitory effects on the carcinogenic potential of MeIQx. Moreover, microarray and quantitative RT-PCR assessment revealed that PhIP induced cytochrome P450 1A1, responsible for both activation and detoxification of HCAs, more strongly than MeIQx. It is noteworthy that complex exposure to multiple HCAs is not necessarily associated with increased risk of carcinogenesis because they are simultaneously and continuously ingested under normal circumstances.     

Hepatic vascular side effects of styrene maleic acid neocarzinostatin in the treatment of hepatocellular carcinoma

Styrene-maleic acid neocarzinostatin (SMANCS) sometimes causes hepatic vascular side effects, including arterial stricture, obstruction, and arterio-portal shunt. A total of 128 intra-arterial SMANCS injection treatments, performed for 89 patients with hepatocellular carcinoma, were analyzed to determine the relationship between angiographic findings and subsequent hepatic vascular injuries. After SMANCS therapy, hepatic arterial stricture or obstruction occurred in 5 patients (5/128; 3.9%), arterio-portal shunting in 12 (12/128; 9.4%), liver shrinkage in 4 (4/128; 3.1%), and cholangitis or biloma in 2 (2/128; 1.6%). Among 23 patients whose plain abdominal X-ray films just after SMANCS injection showed Lipiodol retention in the hepatic artery, 5 patients developed arterial obstruction, 10 developed arterio-portal shunt, and 2, cholangitis or biloma. Among 26 patients with Lipiodol retention in the portal vein, 4 developed hepatic lobe atrophy with aggravation of liver function. Among 3 patients with Lipiodol retention in both the hepatic artery and the portal vein, 1 developed arterio-portal shunt. In 76 treatments without excessive Lipiodol retention, only 1 of the patients developed arterio-portal shunt. Excessive retention of Lipiodol in hepatic vascular beds just after SMANCS therapy was significantly associated with future vascular side effects (22/52 vs 1/76; P < 0.0001). Lipiodol retention in arteries just after SMANCS injection was closely associated with subsequent arterial obstruction or arterio-portal shunt, and Lipiodol retention in the portal vein was related to subsequent hepatic lobe atrophy. Received: April 28, 1999 / Accepted: November 26, 1999     

Primary nonsecretory plasma cell leukemia: a rare variant of multiple myeloma

 We report a patient with primary nonsecretory plasma cell leukemia. These cells resembled prolymphocytes and expressed only CD38 and CD56. Due to the atypical morphology and lack of monoclonal immunoglobulins in both serum and urine, it was difficult to make a correct diagnosis. Electron-microscopic and immunocytochemical cytoplasmic studies were useful. Received: May 4, 1998 / Accepted: September 3, 1998     

Smoking before surgery predicts poor long-term survival in patients with stage I non-small-cell lung carcinomas.

PURPOSE: The majority of lung carcinoma patients requiring resection have smoking habits prior to surgical treatment, and the correlation of smoking with postoperative complications is well known. However, few studies have investigated the correlation between long-term survival and cigarette smoking in patients with primary, resected lung carcinoma. We analyzed the relationship between clinical factors, including cigarette smoking before surgery, and 10-year survival in stage I non-small-cell lung carcinoma (NSCLC). PATIENTS AND METHODS: Cigarette smoking habit and other factors influencing either the overall survival or the disease-specific survival rates of patients with stage I primary, resected NSCLC were evaluated according to the Cox proportional hazards model using a total of 369 patients with stage I-NSCLC. RESULTS: Comparison of the cause of death in patients with 30 or more pack-years and patients with less than 30 pack-years showed significant differences in the prevalence of recurrent disease and onset of nonmalignant disease. Multivariate analysis demonstrated significant correlations between overall survival and age and pack-years. Disease-specific survival showed significant correlations with age, tumor classification, and visceral pleural invasion. CONCLUSION: Smoking pack-years is an important clinical prognostic factor in evaluating overall long-term survival in patients with stage I primary, resected NSCLC.     

Induction of effective antitumor immunity in a mouse brain tumor model using B7-1 (CD80) and intercellular adhesive molecule 1 (ICAM-1; CD54) transfection and recombinant interleukin 12.

Although tumor-specific T lymphocytes recognize tumor-associated antigens (TAA) present on their cell surface via major histocompatibility complex (MHC) molecules, T cells require other activating signals. These are provided by costimulatory molecules, including B7-1 (CD80), B7-2 (CD86) and intercellular adhesive molecule 1 (ICAM-1; CD54). Transfecting mouse tumor cell lines with the B7 gene can lead to primary tumor rejection and the establishment of protective immunity. However, some studies have shown that the B7 effect upon T-cell-dependent tumor immunity is limited. Therefore, we examined the antitumor effects of recombinant interleukin 12 (IL-12) and genetically engineered glioma cells expressing B7-1 or both B7-1 and ICAM-1. Vaccination of mice with B7-1-expressing tumor cells substantially inhibited the growth of subcutaneously inoculated gliomas but not those located in the brain. Vaccination with B7-1-expressing tumor cells and systemic recombinant IL-12 (rIL-12) was more effective than either B7-1-expressing tumor cells or rIL-12 alone. Our murine brain tumor model also showed that vaccination with tumor cells expressing both B7-1 and ICAM-1 combined with rIL-12 prolonged survival. We have demonstrated the therapeutic potential of vaccination with rIL-12 and tumor cells expressing both B7-1 and ICAM-1 in the control of glioma growth.