Inhibition of rabbit gastric epithelial restoration by a water extract ofHelicobacter pylori: evidence using a cultured cell model

The detailed mechanism ofH. pylori-induced gastric damage is still unknown. In this study, we showed that a water extract ofH. pylori retarded the epithelial restoration in a cultured rabbit gastric epithelial cell model with the inhibition of both cell migration and proliferation. Although this inhibitory substance has not yet been biochemically characterized, it is different from knownH. pylori associate-cytotoxins and ammonia. From these results, we hypothesize that these bacteria, directly play a role in disturbance of peptic ulcer healing in vivo. This paper was presented at the Symposium on ‘Cell injury and protection in the gastrointestinal tract: from basic science to clinical perspectives’, October 8–11, 1995, Pécs, Hungary.     

高效液相色谱法测定tRNA~(Ile)的核苷酸组成

用高效液相色谱法(HPLC)分析了纯化的牛肝tRNA~(He)核苷酸组成成份,并根据各成份的峰的面积计算了它们的近似数量。实验表明牛肝tRNA~(He)有76个核苷酸,其中含9种14个稀有碱基。t~6A不能被发现。     

CLINICAL USEFULNESS OF COLONOSCOPIC INSERTION OF A DECOMPRESSION TUBE FOR OBSTRUCTIVE COLORECTAL CANCER

We evaluated the clinical usefulness of colonoscopic insertion of a decompression tube (decompression method) for the treatment of ileus associated with left‐sided colorectal cancer. Decompression method was done in 48 patients with colorectal cancer (38 primary cancer, 10 metastatic cancer). A decompression tube was successfully inserted in all but 10 patients who had primary cancer with severe strictures. The overall insertion rate was 79%. Decompression method improved obstructive symptoms and decreased intestinal gas as evaluated on plain X‐ray films of the abdomen. Emergency operation was unnecessary in 96% of the patients with primary cancers, in whom the decompression tube was successfully inserted. We conclude that decompression method can improve abdominal symptoms caused by obstructive colorectal cancer and reduce the need for emergency operation.     

Hypersusceptibility to DMCM-induced seizures during diazepam withdrawal in mice: evidence for upregulation of NMDA receptors

The present study investigated the role of NMDA (N-methyl-D-aspartate) receptors in the hypersusceptibility to seizures induced by the benzodiazepine inverse agonist DMCM (methyl-6,7-dimethoxy-4-ethyl-β-carboline-3-carboxylate) during diazepam withdrawal The seizure threshold of DMCM was markedly decreased during diazepam withdrawal, reflecting withdrawal hyperexcitability in response to physical dependence. The decrease in the seizure threshold of DMCM in diazepam-withdrawn mice was inhibited by the non-competitive NMDA receptor antagonists MK-801 ((+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)cycloheptan-5,10-imine maleate; 50 μg/kg, s.c.) and ifenprodil (20 mg/kg, i.p.). The effective doses of these compounds were lower than those required to prevent DMCM-induced seizures in chronically vehicle-treated mice. Since MK-801 and ifenprodil do not only bind to NMDA receptors but also to σ receptors, the present study also investigated the effects of σ receptor ligands. The decrease in the seizure threshold of DMCM in diazepam-withdrawn mice was not modified by the σ receptor agonist, (+)-pentazocine (5 mg/kg, s.c.), or the σ receptor antagonist, NE-100 (N,N-dipropyl-2-[4-methoxy-3-(2-phenylethoxy)phenyl]-ethylamine monohydrochloride; 5 mg/kg, i.p.). Furthermore, the latency to the expression of wild running induced by intracerebroventricular administration of NMDA (60 ng/mouse) was also significantly lower in diazepam-withdrawn mice than in vehicle-treated control mice. On the other hand, there was no difference in the spermidine concentration between vehicle-treated control and diazepam-withdrawn mice. In a receptor binding experiment, the B_max value for [³H]-MK-801 binding was significantly increased in cerebrocortical tissues from diazepam-withdrawn mice, while the K_d value did not change in either group. However, the acute addition of a high concentration of diazepam (10 and 100 μM) in vitro did not alter [³H]-MK-801 binding in cerebrocortical membrane preparations. The behavioral experiments suggest that NMDA receptor antagonists may suppress benzodiazepine withdrawal responses, while the biochemical study reveals upregulation of the NMDA receptor, which may play an important role in the hypersusceptibility to DMCM-induced seizure in diazepam-withdrawn mice. Received: 23 July 1997 / Accepted: 27 November 1997     

A case of amyopathic dermatomyositis with acute interstitial pneumonia (DAD pattern)]

A 61-year-old man was admitted to our hospital because of edematous erythema on his upper eyelids and dry cough. No subjective nor objective findings suggestive of skeletal muscle involvement, such as muscle weakness and elevated levels of aldolase and creatine phosphokinase were noted. Chest high-resolution computed tomography revealed a ground glass opacity and consolidation of his lower lung. Skin biopsy findings were compatible with dermatomyositis. Therefore, he was diagnosed as amyopathic dermatomyositis (ADM) with acute interstitial pneumonia and treatment with steroid pulse therapy was started. Since histological evaluation showed diffuse alveolar damage during the initial treatment, the treatment was changed into the combination therapy of prednisolone and cyclosporine. However, his acute interstitial pneumonia did not respond to this treatment and passed away by aggravation of a breathing state and concurrence of disseminated intravascular coagulation. Japanese patients with ADM have been shown to be more frequently associated with intractable acute interstitial pneumonia than Caucasian patients, suggesting that the racial difference influences the occurrence of acute interstitial pneumonia in ADM. Since autoantibodies specific for ADM have not been detected, we performed immunoprecipitation analysis using 35S methionine-labeled K562 cells to identify them. His sera immunoprecipitated a polypeptide of 140 kDa. The 140 kDa polypeptide might be one of autoantibodies specific for ADM with acute interstitial pneumonia, although future analysis using a larger number of patients with ADM will be required to confirm this result.     

The UPAO test in preoperative evaluation for major pulmonary resection: an operative case with markedly improved ventilatory function after radical pulmonary resection for lung cancer associated with pulmonary emphysema.

A 65-year-old man was admitted to our hospital for treatment of a squamous cell carcinoma in his right lung. Respiratory function testing showed an extremely reduced forced expiratory volume in 1 second (FEV1) of 1.0 l (29.9% of predicted), and a reduced FEV1/FVC ratio of 24.1%. Arterial blood gases on room air showed a pH of 7.41, a PaCO(2) of 36.7 mmHg, and a PaO(2) of 79.3 mmHg. To assess the predictive postoperative cardiopulmonary function, unilateral pulmonary artery occlusion (UPAO) testing was performed. In the condition of right main PA occlusion, the mean pulmonary artery pressure (mPAP), cardiac index (CI) and total pulmonary vessel resistance index (TPVRI) was 18 mmHg, 3.2 l/min/m(2) and 443.37 dyne.sec.cm(-5)/m(2), respectively. He underwent a middle lobectomy with combined partial resection of both the upper and lower lobes. He also underwent simultaneous resection of a giant bulla arising from the right upper lobe as lung volume reduction surgery. At 80 days after the operation, his FEV1 rose to 1.88 l, and the PaO(2) on room air was improved to 88.9 mmHg. UPAO testing was suggested to be more useful than routine pulmonary function test to determine the accurate predictive postoperative cardiopulmonary function and to decide indication for a radical operation.     

Carbohydrate structures of human alpha-fetoprotein of patients with hepatocellular carcinoma: presence of fucosylated and non-fucosylated triantennary glycans.

Chemical structures of the sugar chains of various human alpha-fetoprotein (AFP) species with different affinity for Concanavalin A (Con A) and Lens culinaris agglutinin (LCA) were examined by pyridylamination of their oligosaccharides and stepwise exoglycosidase digestion. Using reversed-phase and size-fractionation high performance liquid chromatography systems we identified six pyridylamino-sugar chains. The Con A-reactive and LCA-nonreactive species of AFP from patients with hepatocellular carcinoma contained a biantennary sugar chain, and the Con A-reactive and LCA-reactive species had a biantennary one with a fucose residue at the innermost N-acetylglucosamine residue. The Con A-nonreactive and LCA-reactive species contained a biantennary sugar chain both with a bisecting-N-acetylglucosamine residue at the trimannosyl core and with a focus residue at the innermost N-acetylglucosamine residue. The Con A-nonreactive and LCA-nonreactive species contained a fucosylated triantennary sugar chain as a major component, and two minor components: a triantennary sugar chain and a biantennary sugar chain with a bisecting-N-acetylglucosamine residue at the trimannosyl core. Thus, the fucosylated and non-fucosylated triantennary sugar chains were newly identified in human AFP. Essentially identical results were obtained for AFP from the patient with gallbladder carcinoma which metastasizes to the liver. These results indicate that the increment in fucosylation and branching to form new antennae is a characteristic feature of the carbohydrate chains of AFP from patients with neoplastic diseases of the liver.     

A novel missense mutation, F826Y, in the mineralocorticoid receptor gene in Japanese hypertensives: its implications for clinical phenotypes.

A gain-of-function mutation resulting in the S810L amino acid substitution in the hormone-binding domain of the mineralocorticoid receptor (MR, locus symbol NR3C2) is responsible for early-onset hypertension that is exacerbated in pregnancy. The objective of this study was to test whether other types of missense mutations in the hormone-binding domain could be implicated in hypertension in Japanese. Here, we screened 942 Japanese patients with hypertension for the S810L mutation in exon 6 in the MR. We did not identify the S810L mutation in our hypertensive population, indicating that S810L does not play a major role in the etiology of essential hypertension in Japanese. However, we identified a novel missense mutation, F826Y, in three patients in a heterozygous state, in addition to four single nucleotide polymorphisms, including one synonymous mutation (L809L). The F826Y mutation is present in the MR hormone-binding domain and might affect the ligand affinity. The F826Y mutation was also identified in 13 individuals (5 hypertensives and 8 normotensives) in a Japanese general population (n=3,655). The allele frequency was 0.00178. The frequencies of the F826Y mutation in the hypertensive population (3/942) and in the hypertensive group (5/ 1,480) and the normotensive group (8/2,175) in the general population were not significantly different, suggesting that this mutation does not greatly affect hypertension. Although it is unclear at present whether or not the F826Y mutation makes a substantial contribution to the mineralocorticoid receptor activity, this missense mutation may contribute, to some extent, to clinical phenotypes through its effects on MR.     

Synaptic relationships between axon terminals from the mediodorsal thalamic nucleus and layer III pyramidal cells in the prelimbic cortex of the rat

A combined study of anterograde axonal degeneration and Golgi electron microscopic technique was designed to examine the distribution and density of axon terminals from the mediodorsal thalamic nucleus (MD) over layer III pyramidal cells in the prelimbic cortex of the rat. The reconstructive analysis of serial ultrathin sections of gold-toned apical and basal dendrites of layer III pyramidal cells showed that degenerating thalamocortical axon terminals from MD formed asymmetrical synaptic contacts predominantly with dendritic spines of the identified basal dendrites as well as apical dendrites. There was little difference in the numerical density of thalamocortical synapses from MD per unit length of both apical and basal dendrites.