A New Pacemaker for Monitoring Asystole and Prevention of Adams-Stokes Syndrome and Sudden Cardiac Death

Patients with suspected Adams-Stokes syndrome are examined by Holter monitoring. During the monitoring, there is the danger of syncopes occurring and there are even reports of sudden cardiac death. We therefore developed a pacemaker for cardiac arrest monitoring and the prevention of Adams-Stokes syndrome and sudden cardiac death, which has the following functions: (1) the longest escape interval of the pacemaker not exceeding the value at which syncope is induced is determined by the decline of the mean heart rate including the asystole to a certain threshold rate; (2) once the pacemaker escapes from the interval it continues pacing for a while at a physiological rate to allow recover from ischemias in organs or tissues; and (3) to prevent overdrive suppression to the heart, the pacing rate gradually declines and stops pacing until the next asystole. This pacemaker is useful not only in the diagnosis of Adams-Stokes syndrome but also in pharmacological and pathophysiological studies and in determining when pacing should cease.     

Intestinal Brush-border Membrane Transport of Monocarboxylic Acids Mediated by Proton-coupled Transport and Anion Antiport Mechanisms

Intestinal brush-border membrane transport of monocarboxylic acids was investigated by using rabbit intestinal brush-border membrane vesicles (BBMVs) and isolated intestinal tissues mounted on Ussing-type chambers. [³H]Mevalonic acid uptake by BBMVs showed an overshoot phenomenon in the presence of an inwardly directed proton gradient, but not in the presence of an inwardly directed sodium gradient or an outwardly directed HCO₃^? or chloride gradient. Initial uptake of mevalonic acid was saturable in the presence of a proton gradient. Uptake of [³H]mevalonic acid was inhibited by various monocarboxylic acids, including acetic acid, benzoic acid, lactic acid, nicotinic acid, pravastatin, salicylic acid and valproic acid, but not by dicarboxylic acid or amino acids. Acetic acid, which is transported by both anion antiport and proton-coupled transport systems, induced serosal bicarbonate-dependent alkalinization in the mucosal-side bathing solution of rabbit jejunal tissues, when examined in Ussing-type chambers. Pravastatin, which is a structural analogue of mevalonic acid and is absorbed via proton-coupled transport like mevalonic acid, did not. The result demonstrates that acetic acid is transported by the bicarbonate-dependent anion antiport system, whereas pravastatin is not. So, it is suggested that monocarboxylic acids are transported by at least two independent transporters, namely, a proton-coupled transporter for most monocarboxylic acids, including mevalonic acid, pravastatin and acetic acid, and an anion antiporter for acetic acid, but not for mevalonic acid or pravastatin. Activation of anion antiporter can induce HCO₃^? secretion in intact intestine.     

Primary Adrenocortical Carcinoma and Ganglioneuroblastoma Followed by Rhabdomyosarcoma in a Child: A Case Report

We report a case of a young child affected by triple cancerswho developed a pleomorphic rhabdomyosarcoma of the retroperitoneumfollowing prophylactic chemotherapy after surgery for doubleprimary adrenocortical carcinoma and ganglioneuroblastoma. It is suggested that genetic susceptibility and chemotherapymight be responsible for the development of rhabdomyosarcomaas the second malignant neoplasm.     

Diagnostic Significance of Two Fetal Proteins, {alpha}f and r{beta}s, in Hepatoma and Other Neoplastic Diseases

Incidences of f and rßs components were studied inserum samples from patients with various malignant and non-malignantdiseases. With the micro-Ouchterlony method, af was detectedexclusively in cases of hepatocellular carcinoma of which theincidence was 83.5%, whereas the incidence of rßswas 47.7%. However, rßs was also detected in somemalignant disease other than hepatocellular carcinoma, withan incidence of 16.5%, and was also detected in a small numberof cases of non-neoplastic liver diseases. Though not tumor-specific, rßs as one of the fetalserum proteins can be detected in cases of non-f-producing hepatomaand in cases of malignancies other than hepatoma. Thus, thedetection of this protein may be of diagnostic significance.Possible mechanism of the appearance of this protein in theblood was discussed.     

Prestretch potentiation of human skeletal muscle during ballistic movement

The conditions associated prior to and during the transition from prestretch to shortering may have considerable influence on the final performance of muscle. In the present study male subjects of good physical condition performed vertical jumps on the force-platform with and without preliminary counter movement. In the counter movement jump (CMJ) the amplitude of the knee bending, velocity of the prestretch and the force attained at end of prestretch were the primary parameters of interest. In addition the coupling time indicating the transition from the eccentric (prestretch) phase to the concentric phase was recorded from the angular displacement and reaction force curves. In the final calculation the mechanical performance parameters of CMJ were always compared with those of the jumps performed without counter movement. The results indicated in general first that CMJ enhanced the average concentric force and average mechanical power by 423 N (66%) and 1158 W (81%), respectively. This potentiation effect was the higher the higher was the force at end of prestretch (p<0.001). Similarly, the prestretch speed (p<0.001) and short coupling time (p<0.01) were associated with enhanced performance during the concentric phase. The average coupling time was 23 ms. The results are interpreted through changes in the prestretch conditions to modify the acto-myosin cross-bridge formation so that the storage and utilization of elastic energy is associated with high prestretch speed, high eccentric force and short coupling time. The role of the reflex potentiation is also suggested as additional enhancement of the final performance.     

Studies on Ectopic ACTH-Producing Tumors: III. An Ectopic Melanocyte-Stimulating Hormone: Gel Chromatographic Finding and Time-Lapse Color Change of Frog Skin

On isolation of the main melanocyte-stimulating factor fromthe metastatic liver tumor of islet cell carcinoma of the pancreas,it was found to be a peptide resembling human ß-MSHin the time-lapse skin darkening response of Xenopus frogs,but different in the volume of elution on Sephadex gel chromatography.     

Low levels of apoptosis and proliferative activity in colorectal villous tumors: Comparison with tubular tumors

In order to clarlfy the cell kinetics of colorectal villous tumors (VT), 21 villous adenomatous areas and 12 carcinomatous areas within villous adenomas were investigated for proliferative activity and apoptosis and compared with a series of 41 tubular tumors (TT), demonstrating elements of intramucosal carcinomas as well as tubular adenomas (so-called carcinoma in tubular adenoma). Proliferation was estimated in terms of KI-67 labeling indices and mitotic indices, and apoptosis was assessed by DNA nick-end labeling to give apoptotic Indices. Apoptotic indices of villous adenomatous and carcinomatous regions were significantly lower than the values for their tubular counterparts. Kl-67 labeling indices were also significantly lower for adenoma components. Apoptotic indices, Ki-67 labeling indices and mitotic Indices increased with atypia raised in tubular adenoma components. Correlations of mitotic indices with apoptotic indices, Ki-67 labeling Indices with apoptotic indices and mitotic Indices with Ki-67 labeling indices were found for each villous tumor group and tubular tumor group, and the apoptosis and proliferation ratios for villous tumors were relatively low, suggesting a tendency for greater growth due to less cell deletion. Although this is only one of the biological features of villous tumor groups, it might play a major role in generation of malignancy.     

Renal cell carcinoma in dialysis patients: A single center experience

AIM: Renal cell carcinoma (RCC) is a life-threatening complication of end-stage renal disease with an unclear pathogenesis. We evaluated RCC developing in patients undergoing dialysis. METHODS: In 2624 patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis at our hospital between July 1993 and March 2004, we performed annual screening for RCC using abdominal computed tomography and ultrasonography. Patients diagnosed with RCC underwent radical nephrectomy as well as clinical and pathologic evaluation. RESULTS: RCC was detected in 44 patients (1.68%; 31 males and 13 females). The age of RCC patients was 55.5 +/- 11.1 years. Dialysis duration before RCC diagnosis was 11.2 +/- 7.2 years. Most RCC were early stage and low stage by TNM classification, 43 patients had N0M0 RCC, whereas one had N1M0. Tumor size was 2.9 +/- 1.9 cm. The predominant histological type of RCC was common or conventional cell-type carcinoma (clear cell carcinoma and granular cell carcinoma). Of patients, 5(11.4%) had bilateral RCC, and satellite tumor lesions in RCC were detected in 13 (29.5%). In 36 patients (81.8%) RCC was accompanied by acquired cystic disease of the kidney. These patients had longer dialysis durations (P = 0.01) and smaller tumors (P = 0.048). RCC metastasized postoperatively in 4 patients (9.1%), while one (2.3%) died of cancer. CONCLUSIONS: Our dialysis patients showed a higher incidence of RCC than the general population. Prognosis was favorable because tumors were detected by screening when they were small. Therefore, periodical screening for RCC seems very important in dialysis patients.