Changes in wall shear stress magnitude after aneurysm rupture

Computational fluid dynamics (CFD) studies on cerebral aneurysms have attempted to identify surrogate hemodynamic parameters to predict rupture risk. We present a case of bilateral mirror image aneurysms, one of which ruptured soon after imaging. Wall shear stress values of the ruptured aneurysm changed by 20–30 % after rupture because of change in the aneurysm shape. Findings from our case suggest that CFD studies comparing unruptured and ruptured aneurysms may not yield valid estimation on aneurysm rupture risk because of changes in aneurysm shape after rupture. Changes in aneurysm shape after rupture should be considered in CFD research.     

Comparative evaluation of image quality among different detector configurations using area detector computed tomography

The 320-detector row computed tomography (CT) system, i.e., the area detector CT (ADCT), can perform helical scanning with detector configurations of 4-, 16-, 32-, 64-, 80-, 100-, and 160-detector rows for routine CT examinations. This phantom study aimed to compare the quality of images obtained using helical scan mode with different detector configurations. The image quality was measured using modulation transfer function (MTF) and noise power spectrum (NPS). The system performance function (SP), based on the pre-whitening theorem, was calculated as MTF²/NPS, and compared between configurations. Five detector configurations, i.e., 0.5 × 16 mm (16 row), 0.5 × 64 mm (64 row), 0.5 × 80 mm (80 row), 0.5 × 100 mm (100 row), and 0.5 × 160 mm (160 row), were compared using a constant volume CT dose index (CTDI_vol) of 25 mGy, simulating the scan of an adult abdomen, and with a constant effective mAs value. The MTF was measured using the wire method, and the NPS was measured from images of a 20-cm diameter phantom with uniform content. The SP of 80-row configuration was the best, for the constant CTDI_vol, followed by the 64-, 160-, 16-, and 100-row configurations. The decrease in the rate of the 100- and 160-row configurations from the 80-row configuration was approximately 30%. For the constant effective mAs, the SPs of the 100-row and 160-row configurations were significantly lower, compared with the other three detector configurations. The 80- and 64-row configurations were adequate in cases that required dose efficiency rather than scan speed.     

Impact of venous invasion on the efficacy of adjuvant chemotherapy in elderly patients with stage III colorectal cancer

One of the reasons for the underuse of adjuvant chemotherapy in elderly patients with stage III colorectal cancer is a small survival benefit. This retrospective study sought to identify the predictive factors for elderly patients who could obtain a sufficient survival benefit. We reviewed the data of 1354 elderly patients (aged ≥70 years) with stage III colorectal cancer who underwent complete resection between January 1997 and December 2006. The efficacy of adjuvant chemotherapy was assessed, and the risk factors for recurrence were determined. The efficacy of adjuvant chemotherapy was also assessed after stratification for the above-mentioned risk factors for recurrence. There was a tendency for adjuvant chemotherapy to be effective in elderly patients (hazard ratio 0.84; 95% CI 0.70–1.01). Age, tumor location, pathology findings, tumor depth, venous invasion and lymph node metastasis were identified to be independent risk factors for recurrence by univariate and multivariate analyses. Among these factors, adjuvant chemotherapy was much effective in the elderly patients with high venous invasion (v2-3) (hazard ratio 0.69; 95% CI 0.52–0.91). High venous invasion (v2-3) was identified to be a predictive factor for elderly patients with stage III colorectal cancer who gained a sufficient survival benefit.     

Endoscopic mucosal resection of a rectal malakoplakia in a healthy adult

Malakoplakia in the gastrointestinal tract is rare in healthy young people without underlying disease. Sufficient tissue is required for accurate diagnosis. We describe a malakoplakia that developed in a healthy young woman and was treated by endoscopic mucosal resection (EMR). A 40‐year‐old woman with a history of taking oral contraceptives until one year earlier was referred to our hospital with anal bleeding and constipation. A colonoscopy carried out at our another hospital 18 months earlier disclosed no abnormal findings. Colonoscopy at presentation revealed a yellowish‐white tumor, 5 mm in diameter, in the rectum. The lesion was slightly protruded and had a smooth flat surface, without erosion or ulceration. EMR was carried out for a definitive diagnosis. Histopathological examination showed that the tumor contained granular histiocytes, positive for CD68 and negative forcytokeratin (AE1/AE3). Several histiocytes contained intracytoplasmic round bodies (Michaelis–Gutmann bodies), which reacted positively with periodic acid‐Schiff and calcium (Von Kossa) stains. Intracytoplasmic Escherichia coli (von Hansemann bodies) were identified by Giemsa staining. Based on these results, the tumor in the rectum was diagnosed as a malakoplakia. Following EMR, the patient did not receive further treatment for malakoplakia because she had no symptoms associated with malakoplakia. She has been well for more than 9 months, with no symptoms of disease. Awareness of colorectal malakoplakia is important in patients taking steroids, including oral contraceptives.     

RE‐EPITHELIALIZATION OF SQUAMOUS EPITHELIUM FOR A RADIATION‐INDUCED RECTAL ULCER WHILE GIVING AN ECABET SODIUM ENEMA

The present patient developed a severe rectal ulcer more than 1 month after having received external beam radiation therapy for prostate cancer. Surveillance endoscopy every 3 months demonstrated healing of this rectal ulcer using a novel therapy. He was given enemas with ecabet sodium, which provides physical protection and promotes healing by increasing prostaglandin E₂, and this process induced squamous metaplasia that halted the progression of the ulcer of radiation proctitis as a late‐phase reaction. Intrapapillary capillary loops were visualized with magnified narrow band imaging at the healing ulcer site as seen via the esophagus and, moreover, demonstrated histologically.     

Square-stepping exercise and fall risk factors in older adults: a single-blind, randomized controlled trial

BACKGROUND: Decreased fitness of the lower extremities is a potentially modifiable fall risk factor. This study aimed to compare two exercise programs--square-stepping exercise (SSE), which is a low-cost indoor program, and walking--for improving the fitness of the lower extremities. METHODS: We randomly allocated 68 community-dwelling older adults (age 65-74 years) to either the SSE or walking group (W group). During the 12-week regimen, the SSE group participated in 70-minute exercise sessions conducted twice a week at a local health center, and the W group participated in outdoor supervised walking sessions conducted weekly. The W group was instructed to increase the number of daily steps. Prior to and after the program, we obtained information on 11 physical performance tests for known fall risk factors and 3 self-reported scales. The fall incidence was followed-up for 8 months. RESULTS: At 12 weeks postregimen, significant differences were observed between the two exercise groups with respect to leg power (1 item), balance (2 items), agility (2 items), reaction time (2 items), and a self-reported scale (1 item); the SSE group demonstrated a marked improvement in the above-mentioned items with Group x Time interactions. Significant time effects were observed in the tests involving chair stands, functional reach, and standing up from a lying-down position without Group x Time interactions. During the follow-up period, the fall rates per person-year in the SSE and W groups were 23.4% and 33.3%, respectively (p =.31). CONCLUSION: Although further studies are required, SSE is apparently more effective than walking in reducing fall risk factors, and it appears that it may be recommended as a health promotion exercise in older adults.     

Health benefits associated with exercise habituation in older Japanese men

BACKGROUND AND AIMS: The purpose of this study was to compare the effects of exercise habituation (3-32 years, mean 13.2 years) on physical vitality among five different groups. METHODS: One hundred and two independent, community-dwelling elderly Japanese men, aged 64.6 +/- 6.6 years, were recruited as subjects. The vital age test battery consisted of various coronary heart disease risk factors and physical fitness elements. RESULTS: The results of analysis of variance revealed that vital age as an index of physical vitality was youngest in joggers (47.9 yr, N=18), intermediate in trekkers (55.8 yr, N=20) and walkers (59.1 yr, N=18), and oldest (69.6 yr, N=20) in patients with ischemic heart disease (IHD). The difference between chronological age and vital age was approximately 15 years (p<0.05) in joggers, and 8 years (p<0.05) in trekkers and walkers. The vital age of sedentary persons (N=26) was only 1.9 years (NS) younger than their chronological age, which was similar to the difference (vital age of 64.1 +/- 8.5 yr vs chronological age of 65.7 +/- 5.4 yr) previously observed in similarly aged exercising IHD patients. CONCLUSIONS: These results indicate that exercise habituation significantly affects the overall health status of most individuals, irrespective of mode of exercise. Among the three modes of exercise, jogging may be most beneficial. Furthermore, regularly exercising coronary patients may have physical vitality similar to that of sedentary men.     

Effect of cilostazol, a phosphodiesterase inhibitor, on carotid IMT in Japanese type 2 diabetic patients

The aim of this study was to investigate the effect of cilostazol, a cAMP phosphodiesterase inhibitor, on carotid artery intima-media thickness (IMT) and on the incidence of cardiovascular events in Japanese subjects with type 2 diabetes. A total of 62 type 2 diabetic subjects were allocated equally to the cilostazol treatment group (n = 31) and the control group (n = 31). Carotid IMT was evaluated before and after treatment using B-mode ultrasonography. After the study period (mean +/- SD: 2.6 +/- 0.17 years), carotid IMT showed a significantly greater increase in the control group than in the cilostazol group (0.12 +/- 0.14 mm vs. 0.04 +/- 0.02 mm, p < 0.05). In the control group, 1 out of 31 patients suffered from symptomatic cerebral infarction and 1 had angina pectoris during the observation period. On the other hand, no subject in the cilostazol group developed cardiovascular events during the study period. At baseline, the diabetic patients given cilostazol had a significantly lower HbA1c level than the control subjects, but the other atherosclerotic risk factors (BMI, blood pressure, and serum lipids) and the duration of diabetes did not differ between the two groups. These results indicate that cilostazol therapy can attenuate the increase of carotid artery IMT in Japanese subjects with type 2 diabetes.