The beneficial effects of 40% and 100% O2 inhalations on acutely-induced myocardial ischemia in dogs

The effectiveness of O2 inhalation on the acutely-induced ischemic myocardium in dogs was investigated. In 22 open-chest mongrel dogs, the left anterior descending coronary artery was partially occluded to reduce coronary flow. The regional coronary vein accompanying the artery was cannulated to obtain coronary venous blood. Switching of inspiratory gas from room air to 40% O2 produced an elevation of coronary venous O2 saturation from 35.8 +/- 12.7 (S.D.) to 41.1 +/- 11.9% and shifting of myocardial lactate production to utilization (from -0.9 +/- 36.9 to 5.0 +/- 36.7%), indicating that 40% O2 inhalation ameliorated ischemia. Application of 100% O2 inhalation caused even more beneficial effects; coronary venous O2 saturation was elevated to 50.6 +/- 12.6% and myocardial lactate extraction was improved to 7.8 +/- 40.5%. The present study indicated that 40% O2 inhalation was effective and 100% O2 inhalation even more effective in ameliorating acutely-induced myocardial ischemia. Decreases in myocardial contractile force and left ventricular size and suppression of sympathoadrenal activity might be possible mechanisms for these beneficial effects.     

Current state and effectiveness of abdominal ultrasonography in complete medical screening

Purpose The current state and effectiveness of abdominal ultrasonography (US) were investigated by reviewing statistical data for US of the kidney as part of complete medical screenings conducted at our institution between April 1994 and March 2004. Methods Among 4339 individuals with US findings, computed tomography (CT) was performed on 129 individuals at our institution. Among these individuals, US findings and CT diagnoses were compared and analyzed. Results US findings indicated renal tumors in 73 of the 129 subjects, and the breakdown of CT diagnoses for these 73 individuals was as follows: no lesion, n = 45 (61.6%); simple renal cyst, n = 13 (17.8%); complicated renal cyst, n = 5 (6.8%); suspected malignant tumor, n = 5 (6.8%); renal angiomyolipoma, n = 2 (2.7%); pelvic dilatation, n = 1 (1.4%); granuloma, n = 1 (1.4%); teratoma, n = 1 (1.4%). Magnetic resonance imaging (MRI) was performed on 4 of the 5 subjects with suspected malignant tumor, and surgery was performed in all 4 cases with suspected kidney cancer. Kidney cancer was histopathologically confirmed in 2 patients, resulting in a detection rate of 0.046% for kidney cancer by US as part of a complete medical screening. In the 2 patients with kidney cancer, differentiating cystic renal cell cancer from a renal cyst was not possible based on US findings alone in 1 patient, and no thorough examinations were performed in the 3 years leading up to surgery. Conclusions These results suggest that additional US and thorough examinations are necessary if a lesion cannot be confirmed as a simple renal cyst on initial US. Furthermore, to improve the skill levels of healthcare professionals who perform and interpret US, a feedback system should be established where data related to complete medical screenings are available to the personnel involved.     

Quantification of the Learning Curve for Arthroscopic Os Trigonum Excision

The purpose of the present study was to quantify the learning curve for arthroscopic os trigonum excision using the log-linear model. Twenty-three consecutive feet underwent arthroscopic os trigonum excision and release of the flexor hallucis longus. The required time from the beginning of shaving of the soft tissue until completion of os trigonum excision and release of the flexor hallucis longus (van Dijk time) was recorded. Regression analysis was applied to predict the required time on the basis of the cumulative case volume after logarithmic transformation of both statistics. The mean required time was 35.2 (range 9 to 90) minutes. After logarithmic transformation, a significant linear correlation was observed between the required time and the cumulative case volume (p?=?.0043). The best-fit linear equation was calculated as log (y, estimated required time)? = ?0.41 log (x, case volume) + 1.86, resulting in an estimated learning rate of 75.3% (= 2^?0.41). The results showed an overall time reduction in arthroscopic os trigonum excision in support of a learning curve effect with an ~75% learning rate, indicating that the required time for arthroscopic os trigonum excision can decrease by ≤25% when the cumulative volume of cases has doubled.     

Alzheimer's disease: Report of two autopsy cases with a clinical diagnosis of corticobasal degeneration

Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Corticobasal degeneration (CBD) is a rare neurodegenerative disease affecting adults, being characterized clinically by a combination of extrapyramidal signs and focal cortical syndromes. In both diseases, tau deposits are a characteristic neuropathological feature. We report two new patients with autopsy‐proven AD, in whom clinical diagnoses of CBD were made during life. The ages of the patients at onset were 52 and 67 years, and the disease durations were 9 and 15 years, respectively. At autopsy, both cases exhibited marked cortical atrophy with evident neuronal loss in the convex areas of the frontal and parietal lobes. Immunohistochemically, AT8‐positive neurofibrillary tangles (NFTs) and Aβ‐positive senile plaques (SPs) were widespread and abundant in the cerebral cortex (Alzheimer pathology stage VI/C of Braak and Braak), leading us to the final pathological diagnosis of AD. No tau lesions suggestive of CBD were observed, and the deep gray matter areas, including the substantia nigra, were unremarkable (exceptionally, only mild neuronal loss was noted in the putamen in case 2). These findings further strengthen the idea that in AD, neurodegeneration with tau and Aβ deposits may begin in the fronto‐parietal neocortical areas, which are often preferentially affected in CBD, earlier than, or as early as the medial temporal lobe, and that extrapyramidal signs, such as rigidity and tremor, can occur in the absence of neuronal loss in the basal ganglia and substantia nigra.     

Usefulness of computed tomography in the diagnosis of an overdose

Computed tomography (CT) is superior for the detection of substances with low radiolucency in comparison with abdominal roentgenograms. In the present study, medical chart review was retrospectively performed for patients who were admitted and underwent plain CT including the stomach on arrival to investigate whether CT is useful for diagnosing overdose (OD). The subjects were divided into patients with OD who did not undergo gastric lavage (OD group) and those without OD (Control group). The presence of a radiopaque area (Hounsfield number over 100 on a range of interest of 3 mm2) in the stomach on CT was defined as a positive finding. The average Glasgow Coma Scale in the OD group (n=11) was significantly lower than that in the Control group (n=137). Positive findings on CT were found more frequently in the OD group than in the Control group (100 vs. 19.7%, p＜0.0001). Based on the finding of a high-density deposition in the bottom of the stomach, the CT predicted OD with 98.5% specificity. Accordingly, CT findings of a high-density deposition in the stomach of a patient with a diminished consciousness may suggest the presence of a recent overdose.     

Is metabolic syndrome a risk factor for carotid atherosclerosis in normotensive and prehypertensive individuals?

AIM: We have investigated whether metabolic syndrome is a risk factor for carotid atherosclerosis also in normotensive or prehypertensive individuals. METHODS: We analyzed the data from 851 subjects who had a blood pressure of less than 140/90 mmHg and were not taking antihypertensive medication. Metabolic syndrome was defined according to three different criteria: Japan criteria (Japan-MetS); those of the National Cholesterol Education Program (NCEP)-Adult Treatment Panel III (ATP III) (NCEP-MetS); and modified NCEP-ATP III criteria in which body mass index was used as a surrogate for waist circumference (modified NCEP-MetS). RESULTS: Japan-MetS, NCEP-MetS, and modified NCEP-MetS were found, respectively, in 1%, 4%, and 4%, of women, and in 10%, 5%, and 9%, of men. After the adjustment for gender and age, the association between MetS and carotid atherosclerosis did not reach statistical significance. CONCLUSION: Although the number of enrolled subjects was relatively small, these data may further support the importance of controlling blood pressure within the optimal range for the purpose of preventing atherosclerosis in individuals with metabolic syndrome.     

Multimodality therapy using brachytherapy for caval tumor of hepatocellular carcinoma

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) invading the inferior vena cava will expose patients to a risk of sudden death. Effective therapeutic approaches have not been established for caval tumor. This pilot study was conducted to evaluate the feasibility, safety, and clinical efficacy of multimodality therapy using endovascular brachytherapy with iridium-192 for caval tumor. METHODOLOGY: Six consecutive patients underwent endovascular high-dose-rate brachytherapy. An iridium-192 source was placed adjacent to the caval tumor through a vascular sheath introduced via the femoral vein. The total dose of brachytherapy ranged from 10 to 14Gy (5-7Gy per fraction). Hepatic arterial infusion chemotherapy was used in combination in all patients and external-beam radiotherapy was performed in 5 patients. RESULTS: Endovascular brachytherapy was technically successful in all patients. There were no complications related to brachytherapy. The median period of follow-up was 14.5 months (range, 3-29 months). Complete response and partial response were achieved in 2 (33%) and 4 (67%) patients, respectively. The 1- and 2-year survival rates were 50% and 17%, respectively, with a median survival of 14 months. CONCLUSIONS: Multimodality therapy using endovascular brachytherapy was a feasible, safe, and effective treatment for patients with advanced HCC invading the inferior vena cava.