New theory on the pathogenesis of acute myocardial infarction

Autopsy studies of hearts from 140 patients who had suffered acute myocardial infarction (AMI) and 26 cases of sudden coronary death revealed two distinct types of myocardial cell death: "kinetic cell death" (KD) and "static cell death" (SD). In KD, the predominant type of cell death in AMI-myofibrils disintegrated through alternating overcontraction and overextension. KD was found not only in patients having died after some time had elapsed from the onset of AMI, but also in cases of sudden coronary death. Muscle fibers in SD, which by contrast began to appear at least seven hours after the onset of AMI, characteristically preserved cross striations, while their nuclei were pyknotic or had already disappeared. Such fibers were observed only in territories peripheral to occlusive coronary thrombus, a secondary rather than a primary event that takes place during the course of AMI. As a result of the above observations, we were able to produce a new experimental model of AMI using mongrel dogs. As a preparatory procedure we first injected them intravenously with 2% calcium chloride at a constant rate for 90 or 120 minutes, and then with a sudden injection of caffeine, calcium chloride and catecholamine in order to induce KD. In contrast, ligation of the intraventricular coronary artery near its origin caused SD of myocardial fibers in the dependent territories. Overall results led us to conclude that AMI is initiated by instantaneous overcontraction of myocardial fibers, resulting in their KD, a phenomenon that could be called "myocardial self-destruction."     

Brainstem afferents to the omnipause region in the cat: a horseradish peroxidase study

"Omnipause" neurons (OPNs), located in the nucleus raphe pontis and the reticular formation, actively suppress saccadic eye movements during intersaccadic intervals. To determine the brainstem afferents that may inhibit the OPNs and thereby allow a saccade to occur, we injected horseradish peroxidase into the raphe pontis of four cats at the site of physiologically identified OPNs. Labeled neurons were found in a number of brainstem nuclei. The greatest concentrations, composed of small to medium-sized neurons, were located in a group of nuclei around the habenulopeduncular tract, in the rostral mesencephalic reticular formation, in the deep layers of the superior colliculus, and in parts of the subjacent cuneiform and subcuneiform reticular nuclei. Smaller numbers were found in the nucleus reticularis pontis oralis. Caudal to the injection site, labeled neurons were scattered in parts of the nuclei reticularis gigantocellularis, paragigantocellularis dorsalis, and paragigantocellularis lateralis. A few neurons were labeled in a restricted region of the causal part of the nucleus prepositus hypoglossi and in the nucleus reticularis medullaris ventralis. Larger numbers of neurons were labeled in the dorsal column nuclei and in parts of the cochlear nuclei. Smaller numbers were found in the spinal trigeminal nucleus, the lateral nucleus of the superior olive, and the fastigial nucleus of the cerebellum. The nonreticular brainstem projections may contribute sensory information in a number of modalities since OPNs respond to visual, somesthetic, and auditory stimuli. Our findings indicate a number of regions that may contain neural elements impinging on the OPNs. The best prospects for a saccade initiation signal from one of the labeled populations appear to be the meso-diencephalic reticular formation and/or the superior colliculus.     

Effects of Daily Matcha and Caffeine Intake on Mild Acute Psychological Stress-Related Cognitive Function in Middle-Aged and Older Adults: A Randomized Placebo-Controlled Study

Matcha, a type of green tea, has a higher amino acid content than other types of tea. We previously examined the ability of matcha to improve cognitive function in older adults and determined that continuous matcha intake improves attention and executive function. This study aimed to compare the effects of matcha and caffeine and clarify the differences between these effects. The study was registered at the University Hospital Medical Information Network (UMIN000036578). The effect of single and continuous intake was compared, and the usefulness of continuous intake was evaluated under the stress condition. The Uchida–Kraepelin test (UKT) was used to induce mild acute stress, and the Cognitrax was used to evaluate cognitive function. A single dose of caffeine improved attentional function during or after stress loading. The reduced reaction time in the Cognitrax, observed following a single dose of matcha, was likely due to caffeine. The matcha group showed an increase in the amount of work after continuous intake, whereas the caffeine group only showed an increase in the amount of work for the UKT after a single dose. Ingesting matcha with caffeine improves both attention and work performance when suffering from psychological stress compared with caffeine alone.     

Innovative Fixation Technique for Avulsion Fractures of the Calcaneal Tuberosity

Avulsion fractures of the calcaneal tuberosity, although relatively uncommon, occur more frequently in patients with osteoporosis and in the elderly. The results of closed manipulation are poor in these fractures, usually requiring open reduction and internal fixation. However, it is difficult to fix the bone fragment rigidly, because the avulsed bone fragment is small and thin, and the bone quality of the calcaneal body in the elderly is poor. Hence, it is necessary to limit prolonged weight-bearing after the operation. We performed an innovative surgical procedure of suture fixation to the anchor screw in four cases, following which earlier postoperative rehabilitation with full weight-bearing walking and range of motion exercises was possible, and bony union was achieved without repeated displacement of the fragment in all patients. We believe this technique would prove useful in surgical management of calcaneal tuberosity avulsion fractures.     

Outcome of advanced renal cell carcinoma arising in end-stage renal disease: comparison with sporadic renal cell carcinoma

Clinical and Experimental Nephrology - The data regarding oncological outcome in advanced renal cell carcinoma (RCC) arising in end-stage renal disease (ESRD) are limited. Patients diagnosed with...     

A double-blind trial on the effect of bunazosin hydrochloride for the symptoms of benign prostatic hypertrophy]

A multicenter clinical trial was carried out on 372 patients in double-blind conditions in order to determine the clinical effects of Ea-0643 (bunazosin hydrochloride) on voiding disorders in benign prostatic hypertrophy, compared with paraprost and placebo. Of the 372 patients, 129 were assigned to bunazosin hydrochloride, 118 to paraprost and 125 to placebo. The improvement rating for all five subjective symptoms improved with passage of time in all the bunazosin hydrochloride, paraprost and placebo groups. A higher improvement rating was obtained in the bunazosin hydrochloride group for retarded urination, urinary stream condition and abdominal pressure at voiding, while the improvement rating was higher for prolonged urination in the placebo group and for residual urine in the paraprost group, but there was no significant difference in improvement ratings between the groups. The daily frequency of voiding decreased to a significant extent in the bunazosin hydrochloride and placebo group at week 1, and there was a significant difference between the bunazosin hydrochloride and the paraprost groups and between the placebo and the paraprost groups. The improvement rating for conditions of voiding was higher with the bunazosin hydrochloride group, when "slightly or better improved" cases were taken into account, but there was no difference between the groups. As for objective symptoms, maximum and average flow rate, useful measures for clinical evaluation of drug effects on voiding disorders, were significantly increased, with a decrease to match in residual urine ratio in the bunazosin hydrochloride group. In terms of maximum and average flow rate bunazosin hydrochloride was significantly superior to paraprost at weeks 1 and 2 and superior to placebo at weeks 2 and 4 and at the final evaluation as well. In terms of residual urine ratio bunazosin hydrochloride was superior to both paraprost and placebo. The global improvement rating, as assessed by the U- and chi 2-tests, was significantly higher in the bunazosin hydrochloride group than in the paraprost group, and there was a significant difference in global improvement ratings, as assessed by the chi 2-test, between the placebo and the paraprost groups, when "moderately or better improved" cases were taken into account. The stratified analysis of the prostate glands, subjective symptoms, maximum flow rate and residual urine ratio revealed that in patients with more advanced conditions the bunazosin hydrochloride group showed significantly superior improvement rates than the paraprost and placebo groups.(ABSTRACT TRUNCATED AT 400 WORDS)     

Stereological estimation of mean nuclear volume in bladder cancer--measurement by point sampled intercepts

To obtain objective information about bladder cancer, we measured the mean nuclear volume of bladder cancer cells by using the "Point Sampled Intercepts" method, which was published by Gundersen et al. Thirty one cases of bladder cancer were selected and divided into 2 groups: group A; no recurrence over 3 years after initial TUR (12 cases), group B; cystectomy or cancer death (19 cases). Estimated mean nuclear volume was significantly smaller in group A than in group B. It is suggested that estimation of the mean nuclear volume by this stereological method may provide objective information for predicting the prognosis of patients with bladder cancers. Further studies in additional patients are required to substantiate the predictive potential of this method.     

Spontaneous perforation of the rectosigmoid colon: a report of 2 cases

Spontaneous perforation of rectosigmoid colon is rare but usually results in severe peritonitis, with very high mortality. Two cases of spontaneous rectosigmoid perforations are reported here along with a brief literatures review.