Instability of reference diameter in the evaluation of stenosis after coronary angioplasty: Percent diameter stenosis overestimates dilative effects due to reference diameter reduction

Purpose: To examine changes in the reference segment luminal diameter after coronary angioplasty. Methods: Sixty-one patients with stable angina pectoris or old myocardial infarction were examined. Coronary angiograms were recorded before coronary angioplasty (pre-angioplasty) and immediately after (post-angioplasty), as well as 3 months after. Artery diameters were measured on cine-film using quantitative coronary angiographic analysis. Results: The diameters of the proximal segment not involved in the balloon inflation and segments in the other artery did not change significantly after angioplasty, but the reference segment diameter significantly decreased (4.7%). More than 10% luminal reduction was observed in seven patients (11%) and more than 5% reduction was observed in 25 patients (41%). More than 5% underestimation of the stenosis was observed in 22 patients (36%) when the post-angioplasty reference diameter was used as the reference diameter, compared with when the pre-angioplasty measurement was used and more than 10% underestimation was observed in five patients (8%). Conclusion: This study indicated that evaluation by percent diameter stenosis, with the reference diameter from immediately after angioplasty, overestimates the dilative effects of coronary angioplasty, and that it is thus better to evaluate the efficacy of angioplasty using the absolute diameter in addition to percent luminal stenosis.     

Tumorigenicity of arsenic trioxide to the lung in Syrian golden hamsters by intermittent instillations

The tumorigenicity of arsenic trioxide was investigated in female Syrian golden hamsters which were given a total of 5.25 mg or 3.75 mg as arsenic by intratracheal instillations once a week. As controls, hamsters were treated with the vehicle, phosphate buffer solution. During the total life span, 3 lung adenomas were manifested in 10 hamsters or 2 lung adenomas in another 20 hamsters after 15 instillations of arsenic, while no lung tumor was detected among 35 hamsters in 2 control groups. The results show that arsenic trioxide is tumorigenic to the lung of Syrian golden hamsters.     

Comparison of bare metal stent with pioglitazone versus sirolimus-eluting stent for percutaneous coronary intervention in patients with Type 2 diabetes mellitus

BackgroundDrug-eluting stents (DESs) have been shown to decrease restenosis as compared with bare-metal stents. Recently, thiazolidinediones effectively reduced restenosis and the risk of repeat target vessel revascularization. We conducted a study to compare the performance of a DES with that of a bare-metal stent with pioglitazone in patients with Type 2 diabetes mellitus (DM).MethodsThe study was a prospective cohort trial involving 38 Type 2 diabetic patients referred for coronary stenting who were assigned to either the sirolimus-eluting stent (SES) group or the pioglitazone group. Quantitative coronary angiography was performed at study entry and at 6 months of follow-up to evaluate in-stent late luminal loss and the percentage of the luminal diameter and the rate of restenosis. We also analyzed major adverse cardiac events (MACE) at 12 months.ResultsThere were no significant differences in glycemic control levels or in lipid levels in the two groups at follow up. The insulin and homeostasis model assessment insulin resistance at follow-up were significantly lower in the pioglitazone group than in the SES group. The percentage of restenosis was similar between the SES group and the pioglitazone group. The incidence of MACE at 1 year tended to be lower in the pioglitazone group than in the SES group.ConclusionsThe bare-metal stent with pioglitazone is not inferior to the SES in the present study and is one of therapeutic strategies of percutaneous coronary intervention for patients with DM.     

A Case of Duodenal Duplication

Abstract: Duplication of the duodenum is extremely rare. Including the present case, duodenal duplication in adults has been reported in only 20 cases in Japan. All previously reported cases underwent open surgery, and endoscopic resection has not previously been reported. In this report, we describe a patient in whom a duodenal duplication was endoscopically resectable, demonstrating the usefulness of endoscopic resection for the treatment of this malformation.     

Toxicity to rats of methanol-fueled engine exhaust inhaled continuously for 28 days.

Fischer 344 rats were exposed to three concentrations of exhaust generated by an M85 methanol-fueled engine (methanol with 15% gasoline) without catalyst for 8 h/d, 7 d/wk for 7, 14, 21, or 28 d. Concentration- and time-dependent yellowing of the fur was prominent in all treated groups. Concentration-dependent increases in the erythrocyte count, hematocrit, hemoglobin concentration, formaldehyde in plasma, and carboxyhemoglobin in the erythrocytes, and decrease in serum alkaline phosphatase activity were seen after all exposure periods. Histopathologically, lesions were found in the nasal cavity and lungs after 7 d of exposure. Squamous metaplasia of the respiratory epithelium of level 1 (level of the posterior edge of the upper incisor teeth) lining of the nasoturbinate and/or maxilloturbinate and infiltration of neutrophils into the submucosa, and decreases of Clara cells in the terminal bronchiolus and of cilia in the bronchiolar epithelium, were observed in the high-concentration group (carbon monoxide, 94 ppm; formaldehyde, 6.9 ppm; methanol, 17.9 ppm; nitrogen oxides, 52.7 ppm; nitrogen dioxide, 10.6 ppm). The histopathological extents of several lesions increased slightly with the exposure time. Slight squamous metaplasia and hyperplasia of the respiratory epithelium at level 1 were also observed in the medium-concentration group (one in three of the high-concentration group). No histopathological changes were found in the olfactory epithelium of the nasal cavity. In the low-concentration group (one in nine of the high-concentration group), no marked histopathological changes in these organs were observed. These results may suggest that the lesions observed in the nasal cavity of rats exposed to methanol-fueled engine exhaust were mainly caused by formaldehyde, although other components in the exhaust also may have affected nasal cavity and/or lungs to less extent.     

Effects of glutathione depletion on the acute nephrotoxic potential of arsenite and on arsenic metabolism in hamsters

Our previous study showed that pretreatment with buthionine sulfoximine (BSO), which inhibits glutathione synthesis, results in acute renal failure with oliguria in hamsters ingesting sodium arsenite (5 mg As/kg). For a deeper understanding of the relationship between arsenic metabolism and the subsequent development of nephrotoxicity, we studied excretion, tissue retention, biotransformation, pharmacokinetics, and histopathological events in the kidneys of hamsters both with and without BSO pretreatment. The total amount of arsenic excreted in the urine and feces within 72 hr of arsenite administration was more than fivefold lower in BSO-pretreated animals than in the controls without pretreatment (9.2 versus 53.4% of the arsenic dose). The persistence of high amounts of total arsenic was apparent in the blood, liver, and kidneys of BSO-pretreated hamsters, even though the content of inorganic arsenic steadily decreased with time. The disappearance of inorganic arsenic from the blood showed a biphasic elimination pattern characterized first by a rapid component with a half-life of 4.5 hr and second by a slower component with a half-life of 58.0 hr in the BSO-pretreated hamsters, while these half-lives were 0.6 and 11.0 hr, respectively, in the controls. BSO pretreatment not only impaired the excretion of inorganic arsenic, but also impaired its methylation. Combined BSO/arsenite treatment resulted in renal tubular necrosis which was prominent at 1 hr after arsenite administration. By 1 hr, the renal content of inorganic arsenic in the BSO-pretreated animals was 1.7 times higher than that in the controls. This study demonstrates that glutathione depletion elicits the nephrotoxic manifestations of arsenic poisoning.     

Three Cases of Esophageal Granular Cell Tumor

Abstract: Although it has long been thought that granular cell tumor (GCT) is relatively uncommon in the esophagus, in recent years, reports of this disease have increased due to advances in endoscopic examination and endoscopic therapy. The authors recently experienced three cases of esophageal GCT, all of whom underwent endoscopic polypectomy. Endoscopic findings were consistent with Yamada's type I or II, the surface of the lesions being smooth and the color white or whitish-yellow. These three cases were treated by endoscopic polypectomy. In case 1, the resection was made possible by raising the tumor with forceps under a 2-channel-scope. In case 2, the tumor was resectable following submucosal injection of physiological saline. In case 3, the tumor was resected via strangulation with a snare. The lesions described herein were diagnosed as benign and completely resected by polypectomy, though some showed differences in nuclear size or dyskaryosis. As numerous points remain to be clarified regarding the clinical characteristics of this tumor, and some tumors have been diagnosed as malignant despite being small, it appears that endoscopic polypectomy should be performed for the purpose of diagnosis as well as complete resection.     

A randomized comparison of pioglitazone to inhibit restenosis after coronary stenting in patients with type 2 diabetes

OBJECTIVE: Recent studies have demonstrated that the treatment with thiazolidinediones reduces in-stent restenosis. The aim of this study was to elucidate the mechanism of the efficacy of pioglitazone for preventing in-stent restenosis in type 2 diabetic patients. RESEARCH DESIGN AND METHODS: We conducted a prospective, randomized trial involving 54 type 2 diabetic patients referred for coronary stenting who were randomly assigned to either the control or the pioglitazone group. Quantitative coronary angiography was performed at study entry and at 6 months follow-up. Endothelial nitric oxide synthase (eNOS), tumor necrosis factor alpha, interleukin-6, leptin, and adiponectin were measured at study entry and at 6 months follow-up. RESULTS: A total of 28 patients were randomly assigned to the control group, and 26 patients were assigned to the pioglitazone group. There were no significant differences in glycemic control levels or in lipid levels in the two groups at baseline or at follow-up. Insulin, homeostasis model assessment of insulin resistance, eNOS, and leptin at follow-up were significantly reduced in the pioglitazone group compared with the control group. The late luminal loss and in-stent restenosis were significantly less in the pioglitazone group than in the control group. Leptin independently correlated with late luminal loss at multiple regression analysis. CONCLUSIONS: The treatment with pioglitazone in type 2 diabetic patients significantly reduced leptin. This decreased leptin improved insulin resistance and endothelial function with the reduction of insulin. The improved endothelial function affected the reduction of in-stent restenosis.