Human adductor muscles atrophy after short duration of unweighting.

The purpose of this study was to investigate the effect of 20 days of bed rest (BR) on the physiological cross-sectional area (PCSA) of the adductor (AD) muscle group. Five healthy men and five healthy women were kept on a horizontal bed for 20 days. To calculate the PCSA of the AD muscle group, transaxial magnetic resonance imaging of the right thigh was acquired four times for each of the subjects: (1) pre BR, (2) on the tenth day of BR, (3) post BR, and (4) 1 month after BR. Overall, the PCSA measurements of the AD muscle group and its individual muscles were significantly decreased on the tenth day of BR and at post BR; however, they had recovered to the baseline within 1 month of the reambulation period. The amount and pattern of relative change in the PCSA measurements of the AD muscle group were similar to those of the knee extensor (KE) and knee flexor (KF) muscle groups studied previously. These results suggested that the AD muscle group showed an atrophic response that was similar to the KE and KF muscle groups after unweighting; therefore, we should pay much more attention to the AD muscle group when considering countermeasures for future human spaceflight projects.

[Final results of a randomized clinical trial of adjuvant intraportal chemotherapy for colorectal cancer: Intraportal Chemotherapy for Colorectal Cancer Group].

The purpose of the present multi-center collaborative study was to elucidate the efficacy of intraportal chemotherapy with the combination of 5-FU and MMC for the prevention of liver recurrence after resection for colorectal cancer. A total of 125 patients with Stage II, III, and IV colorectal cancer were enrolled in this study between June 1993 and December 1995. Of them, 45 patients were randomized to a portal group: 10 mg/body of mitomycin one shot portal infusion, before and after 500 mg/m2 of 5-FU per 24 h for 7 days portal infusion followed by administration of oral 5-FU. Fifty-three patients were randomized to a control group: oral administration of 5-FU. Twelve patients suffered from temporary mild liver damage. One patient (2%) in the portal group and 6 patients (11%) in the control group developed liver metastases; there was not a significant difference between these two groups regarding development of liver metastases. There was also no significant difference by tumor stage between the portal and control groups regarding development of liver metastases. The 5-year survival rate and 5-year disease-free survival were 84.3% and 81.9%, respectively, in the portal group, and 70.7% and 72.4%, respectively, in the control group; the difference was not significant. Although there was not a significant difference between the portal and control groups regarding the prognosis in stage II, there was a significant difference between the portal and control groups regarding the 5-year disease free survival in stage III (81.1% vs 54.2%). These results suggest that intraportal chemotherapy is effective for stage III colorectal cancer.

Changes in mood status and neurotic levels during a 20-day bed rest.

This study evaluated changes of mood status and depressive and neurotic levels in nine young male subjects during a 20-day 6 degrees head-down tilting bed rest and examined whether exercise training modified these changes. Participants were asked to complete psychometrical inventories on before, during, and after the bed rest experiment. Depressive and neurotic levels were enhanced during bed rest period according to the Japanese version of Zung's Self-rating Depression Scale and the Japanese version of the General Health Questionnaire. Mood state "vigor" was impaired and "confusion" was increased during bed rest and recumbent control periods compared to pre-bed rest and ambulatory control periods according to the Japanese version of Profiles of Mood State, whereas the mood "tension-anxiety", "depression-dejection", "anger-hostility" and "fatigue" were relatively stable during experiment. Isometric exercise training did not modify these results. Microgravity, along with confinement to bed and isolation from familiar environments, induced impairment of mental status.

Effects of rapid saline infusion on orthostatic intolerance and autonomic tone after 20 days bed rest.

To test whether acute volume expansion can normalize orthostatic intolerance and autonomic tone after prolonged bed rest (BR), 23 men were subjected to 20 days BR. Left ventricular (LV) echocardiography was performed during the lower body negative pressure (LBNP) test before and after BR with and without preceding rapid infusion of saline (1,500 ml/30 min). Saline infusion restored heart rate, LV dimension, and stroke volume during LBNP, increased cardiac output (from 4.1 +/- 1 to 5.3 +/- 1 L/min), and normalized LBNP tolerance time (from 11 +/- 4 to 23 +/- 6 minutes). In 9 men, a Holter electrocardiogram was recorded on the day before BR, the fourth and twentieth days of BR, and the day after BR. The high-frequency component of heart rate variability during sleep gradually decreased and reached the lowest level on the day after BR (100%, 66 +/- 16%, 39 +/- 18%, 10 +/- 8%). Thus, restoring decreased blood volume is an effective countermeasure for orthostatic intolerance after BR. However, decreased vagal tone persisted, suggesting reset autonomic tone.

The natural history model of hepatitis C virus infection and the economic evaluation of alpha interferon treatment.

Interferon (IFN) therapy is used for the treatment of hepatitis C virus (HCV) disease, but is so expensive that it creates controversy as to whether or not it is effective use of limited health care resources. In order to make this judgement possible, it must be necessary to build a comprehensive disease model of HCV infection from social perspective. A Markov chain model of the natural history of HCV infection in male patients was developed. Parameters on the clinical phase of the disease were adopted from published reports, but those of the non-clinical phase were estimated from the data on blood donation and mortality rates from the disease. Then, adding in the modeling of treatment outcome from IFN therapy and cost-benefit analysis, IFN therapy was economically evaluated. Using this model, it was shown that (1) IFN therapy for chronic hepatitis C (CHC) would be economically beneficial at least in the Japanese situation, (2) the complete response rate to therapy would be the most sensitive factor affecting outcome, and (3) the younger the person cured by IFN therapy, the greater the benefit seen. These results demonstrate that IFN therapy would be beneficial in the case of the CHC patients (male).

Influence of perioperative blood transfusion on the prognosis of patients with gastric cancer receiving anticancer chemotherapy.

BACKGROUND: The deleterious effect of blood transfusions on survival has been reported in patients with cancers of various organs. However, it remains unclear whether there is any adverse effect of blood transfusion when the patients are administered anticancer drugs after surgery for gastric cancers.METHODS: Data from patients with gastric resection for advanced gastric cancer were retrospectively analyzed to determine the influence of perioperative blood transfusion on the survival rate. All patients were administered anticancer drugs (mitomycin C [MMC] and tegafur-uracil [UFT]). Sixty-nine (33%) of 208 patients received blood transfusion perioperatively, while 139 patients (67%) did not receive transfusion. Multivariate analysis of clinicopathologic prognostic factors, including blood transfusion, was performed. Lymphocyte subsets were measured to investigate the immunosuppressive effect of blood transfusion.RESULTS: The 5-year survival rate was 48.8% in the 69 transfused patients and 66.9% in the 139 non-transfused patients ( P < 0.01). Cox's multiple regression analysis showed that, when patients received anticancer drugs, perioperative blood transfusion was not a significant factor affecting survival after the gastric cancer surgery. However, the CD4/CD8 ratio at 3 months after the surgery was significantly lower in the transfused group than in the non-transfused group.CONCLUSION: Blood transfusion did not affect the survival of operated patients who received postoperative adjuvant chemotherapy. However, the finding that the ratio of CD4/CD8 after surgery was significantly higher in the non-transfused group than in the transfused group supports the notion that transfusion causes broad-spectrum immunosuppression.