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991.
BACKGROUND AND AIM: Clinical features of patients who develop gastric cancer after successful eradication of Helicobacter pylori are still unclear. We attempted to identify host factors associated with the discovery of gastric cancer, including changes in the background gastric mucosa in patients with atrophic gastritis. METHODS: We enrolled 101 patients (59 men, 42 women; mean age 56.0 years) who underwent successful eradication therapy. All patients had no neoplastic lesion in the stomach and were diagnosed with corpus atrophic gastritis histologically before the eradication therapy. After successful eradication, these patients were followed up by an annual endoscopic examination (mean follow-up time 63.2 months; range 12-157 months). Fasting sera were obtained before and after eradication therapy and the serum levels of gastrin/pepsinogens were evaluated. RESULTS: Gastric cancer occurred during follow-up in eight of the 101 patients (7.9%). We compared the host features between the cancer-discovered group (n = 8) and the non-discovered group (n = 93). We found no difference in gender, history of previous treatment of gastric cancer, and serum pepsinogen/gastrin levels at entry between them. The trends in alterations of serum markers did not differ between the two groups. However, gastric cancer was more frequently found in older patients (>54 years at eradication) than in others (P < 0.05). CONCLUSION: Improvement of gastric inflammation did not correlate with the discovery of gastric cancer after eradication; however, age at the time of eradication seemed to be important. Strict follow-up after eradication is needed in older patients with atrophic gastritis.  相似文献   
992.
BACKGROUND: Little is known about the prevalence of hepatitis B virus (HBV) DNA and the genotype distribution among patients with liver diseases in Nepal, where obstruction of the hepatic portion of the inferior vena cava (IVCO) is common. The aim of the present paper was to assess the roles of HBV infection and IVCO in liver cirrhosis (LC) and hepatocellular carcinoma (HCC) in Nepal. METHODS: Serum samples from 121 patients (89 male, 32 female; age, 55.0 +/- 13.6 years) with or without IVCO consisting of 70 LC patients and 51 HCC patients in Nepal, were tested for HBV-DNA. RESULTS: The HBV-DNA was detected in 68 patients (56%) including 20 hepatitis B surface antigen (HBsAg)-negative patients: 33 LC patients (47%) and 35 HCC patients (69%) had detectable HBV-DNA (P = 0.0303). Among the 89 patients with IVCO, HBV-DNA was detected in HCC patients significantly more frequently than in LC patients (80%vs 43%, P = 0.0005). The frequency of HBV viremia was significantly higher among HCC patients with IVCO than those without (80%vs 44%, P = 0.0236), and that of HBV viremia with IVCO was significantly higher among HCC patients than among LC patients (55%vs 27%, P = 0.0153). The HBV genotypes A and D were predominant, and genotype A was significantly more frequent among HCC patients than among LC patients (22%vs 6%, P = 0.0090). Among HCC patients, those with genotype A HBV were significantly younger than those with genotype D (43 +/- 13 vs 57 +/- 12 years, P = 0.0252). CONCLUSION: Hepatitis B virus alone (especially genotype A) or in concert with IVCO may be responsible for development of HCC in Nepal.  相似文献   
993.
We retrospectively reviewed four patients with severe motor and intellectual disabilities (SMID), aged 8-56 years, who presented with ulcerative colitis (UC), and discussed causal interrelationships between UC and SMID. UC started at 3-50 years of age with early childhood-onset in two patients. Two patients had an intractable clinical course in which leukocytapheresis and surgery were ineffective, and resulted in steroid-dependency. We failed to find any causal relationships between infectious events, nutrition and anticonvulsants with the development of UC. However, when occult blood in feces is frequently positive in SMID patients, it is important to consider the possibility of UC and to perform an intestinal endoscopic examination.  相似文献   
994.
Introduction Diagnosing corticobasal degeneration is often difficult on the basis of clinical symptoms and radiological images. We aimed to clarify the imaging findings of corticobasal degeneration syndrome (CBDS). Methods Included in the study were 16 patients (8 men, 8 women, 46–75 years old) with clinically diagnosed CBDS. We evaluated the patients’ symptoms and signs, and MR and single-photon emission CT (SPECT) imaging findings. Results All the patients had cerebral atrophy. Asymmetric cerebral atrophy was observed in 13 patients (81%) predominantly contralateral to the side clinically more affected. Atrophy in the cerebral peduncle was observed in seven patients. FLAIR images showed hyperintensity in the subcortical white matter in the frontoparietal lobes in the clinically more affected side in 14 patients, and in the rolandic region in 13 patients. Asymmetric hypoperfusion in the frontoparietal lobes on SPECT images was observed in all of the patients, and in the basal ganglia in 11 patients. Conclusion CBDS might be unique in showing hyperintensity in the subcortical white matter in the rolandic region on FLAIR images with asymmetric atrophy predominantly contralateral to the side clinically more severely affected. Asymmetric atrophy in the cerebral peduncle without signal abnormalities was also characteristic of CBDS. Atrophy in the midbrain tegmentum was also seen in patients with CBDS.  相似文献   
995.
Helicobacter pylori infection induces chronic gastritis and lowers gastric juice ascorbic acid concentrations. We investigated how H. pylori eradication affected multiple variables that could prevent or delay development of new or occult gastric cancer in patients with early gastric cancer treated by endoscopic mucosal resection. Gastric juice pH, nitrite concentrations, and total vitamin C concentrations, serum concentrations of vitamin C and specific H. pylori antibody, and intensity of neutrophil infiltration in gastric mucosa were determined before and after successful H. pylori eradication. Successful eradication increased acid output and ascorbic acid secretion into gastric juice, accompanied by disappearance of polymorphonuclear infiltration from the surface epithelium and decreased gastric juice nitrite concentrations. Our data suggest that H. pylori eradication decreases the nitrosation rate as the ratio of vitamin C to nitrite increases. This decreases reactive oxygen species and nitric oxide, eliminating their damaging effect on DNA and reducing cell turnover.  相似文献   
996.
We report a female case of variant form of tako-tsubo cardiomyopathy in which wall motion of the distal segment was preserved. In the current case, left ventriculography showed akinesia of the mid portion and normokinesia of the distal and basal portions of the left ventricular chamber. ST-segment elevation was obvious in leads V1-3 rather than in leads V4-6. Because ST-segment elevation is absent in left precordial leads, cardiologists should take care not to fail to diagnose variant form of tako-tsubo cardiomyopathy.  相似文献   
997.
A 76-year-old female with atrial fibrillation and prior cerebral infarction had chest discomfort during rehabilitation for left hemiparesis, and visited the nearby hospital. Her ECG, which was obtained 10 min after the onset, showed marked ST-segment elevation in leads I, II, III, aV(F) and V(2-6), and she was referred to our hospital for cardiac examination. On admission, her ECG, which was obtained 50 min after the onset, showed poor R wave progression and mild ST-segment elevation in leads V(5-6). During only 10 min after the admission, the ST-segment level increased dynamically, and it decreased spontaneously again. Left ventriculography showed akinesia of the mid-to-distal portion and hyperkinesia of the basal portion of the left ventricular chamber, and coronary angiography showed no significant coronary artery disease despite of significant ST-segment elevation. We diagnosed her as having tako-tsubo cardiomyopathy. She was discharged well 10 days later.  相似文献   
998.
A 35-year-old man initially presented with cough and fever. Computed tomography (CT) revealed diffuse small cysts in the lung, and multiple nodules in the liver. Lung and liver biopsies revealed that pathology was consistent with Langerhans cell histiocytosis. Lung shadows increased despite cessation of smoking, whereas the liver involvement improved. After initiating treatment with prednisolone, the chest CT findings improved. However, the liver nodules started to increase while tapering prednisolone. Intravenous etoposide was started, and the liver nodules decreased markedly. The difference in the clinical course between the lung and liver lesions might have been the result of differences in the clonality of these two organs.  相似文献   
999.
Using in vivo patch-clamp technique, the slow oscillation of membrane currents was characterized by its synaptic nature, correlation with electroencephalogram (EEG) and responses to different anesthetic agents, in primary somatosensory cortex (SI) neurons in urethane-anesthetized rats. In more than 90% of the SI neurons, the slow oscillation of the inward currents (0.1-2.5 Hz) with the duration of several hundreds of a millisecond was observed at the holding membrane potential of -70 mV. The reversal potential of the inward currents was approximately 0 mV and was suppressed by application of an alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptor antagonist. In most cases (> 90%) the inward current was synchronized with positive wave of the surface EEG recorded from ipsilateral and even contralateral cortical regions. The frequency as well as duration of the slow oscillation decreased by a volatile anesthetic agent, isoflurane (1.5-5.0%), and excitatory postsynaptic currents (EPSCs) were almost abolished at the highest concentration. Intraperitoneal injection of pentobarbital (25 mg/kg) also decreased the frequency of the slow oscillation without affecting short EPSCs. When gamma-aminobutyric acid A (GABA(A)) receptors were activated by local microinjection of muscimol (3 x 10(-3) m, 1-10 microL) into the thalamus, the frequency of the slow oscillation markedly decreased, but was not abolished completely. These findings suggest that the slow oscillation of the inward currents is generated by the summation of glutamatergic EPSCs, and affected by isoflurane and pentobarbital differently. In addition, GABAergic system in the thalamus can affect the frequency, but is not essentially implicated in the genesis of the slow oscillation.  相似文献   
1000.
OBJECTIVE: Recent reports have shown that patients infected with Helicobacter pylori (H. pylori) have a higher risk of gastric cancer. However, the mechanism of this increased risk is still unclear. In the gastric mucosa, the size of a continuously renewed population of cells is determined by the rates of cell production and of cell loss. Ornithine decarboxylase (ODC) activity is elevated in various gastrointestinal cancers and serves as a marker of mucosal proliferative activity. Apoptosis occurs throughout the gut and is associated with cell loss. Both cell proliferation and cell loss have important roles in H. pylori-associated gastric carcinogenesis. Therefore, we investigated the effect of H. pylori eradication on ODC activity and apoptosis in the gastric mucosa of patients with atrophic gastritis and gastric ulcers. METHODS: Biopsy specimens of the gastric antrum were obtained at endoscopy from 17 H. pylori-positive gastric ulcers patients and 15 H. pylori-positive gastritis patients before and 4 wk after eradication therapy with amoxicillin, omeprazole, and a new anti-ulcer agent, ecabet sodium, and from 10 gastric ulcer patients in whom ulcer healed but H. pylori was left untreated. ODC activity and induction of apoptosis were determined immunohistochemically. RESULTS: H. pylori was successfully eradicated with the triple therapy in 12 (80%) of 15 gastritis patients and 13 (76%) of 17 gastric ulcer patients. ODC activity was present in the gastric mucosa in 21 (84%) patients before eradication but in only four (16%) patients after successful eradication (p = 0.0005). The apoptotic index increased significantly (p = 0.0006) from 4.2% +/- 0.4% before treatment to 7.4% +/- 0.5% after successful eradication. CONCLUSIONS: Successful eradication of H. pylori decreases mucosal ODC activity and increases apoptosis in the gastric mucosa. These findings indicate that by decreasing mucosal cell proliferation and increasing epithelial cell loss, H. pylori eradication may help decrease the subsequent risk of gastric cancer.  相似文献   
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