Endoscopic mucosal resection for early gastric cancer: comparison of two modifications of the cap method.

BACKGROUND AND STUDY AIM: Endoscopic mucosal resection using a cap (EMR-C) is an established method for curative resection of early neoplastic lesions; prelooping of the snare may however be difficult and lead to imprecise resection. We therefore compared two modifications of the conventional technique using outer snare placement with an accessory channel in a prospective, nonrandomized study. PATIENTS AND METHODS: Between October 2004 and March 2007, 54 patients (men 37, women 17; mean age 71 years) underwent EMR. One method involved an internally retained snare (IRS) cap, with a fixed prelooped snare inside the cap; the other method used an externally guided snare (EGS) cap with the snare guided over an oblique cap. The main outcome parameters were specimen size, en bloc resection, and complications. RESULTS: There was no difference between use of the IRS and EGS cap methods in relation to specimen size (27.6 vs. 27.1 mm), or rates of en bloc resection (88.9 % vs. 83.3 %); only one perforation occurred, and this was in the EGS group. CONCLUSION: Both techniques appeared to provide similar efficacy, the inner rim of the IRS cap stabilizes aspiration of the lesion compared with the EGS cap that does not have it.

Evaluation of hydrogen absorption cells for observations of the planetary coronas.

Newly designed Lyman-alpha absorption cells for imaging hydrogen planetary corona were characterized using an ultra high resolution Fourier transform spectrometer installed on the DESIRS (Dichroïsme Et Spectroscopie par Interaction avec le Rayonnement Synchrotron) beamline of Synchrotron SOLEIL in France. The early absorption cell installed in the Japanese Mars orbiter NOZOMI launched in 1998 had not been sufficiently optimized due to its short development time. The new absorption cells are equipped with the ability to change various parameters, such as filament shape, applied power, H2 gas pressure, and geometrical configuration. We found that the optical thickness of the new absorption cell was ∼4 times higher than the earlier one at the center wavelength of Lyman-alpha absorption, by optimizing the condition to promote thermal dissociation of H2 molecules into two H atoms on a hot tungsten filament. The Doppler temperature of planetary coronas could be determined with an accuracy better than 100 K with the performance of the newly developed absorption cell.

Grasping-forceps-assisted endoscopic submucosal dissection using a novel irrigation cap-knife for large superficial early gastric cancer.

The technique of endoscopic submucosal dissection (ESD) needs special skills and involves a long procedure. We therefore developed a new type of dissection knife, the irrigation cap-knife (the Kume cap-knife attachment, which uses a fixed snare), that facilitates ESD by just sliding over the muscle layer with a coagulating current. The ESD procedure using the irrigation cap-knife was performed in seven patients with intramucosal gastric cancer. The tumor was separated from the surrounding normal mucosa using the insulated-tip knife. Submucosal dissection was then performed by pushing our device along the muscle layer while applying a coagulating current, at the same time as a grasping forceps, deployed through the accessory channel, was used to push the lesion away from the muscle layer. The rate of en bloc resection was 100% (7/7). The irrigating cap-knife was extremely useful for ESD of large intramucosal cancers in the stomach.

Gamma-ray detection efficiency of the microchannel plate installed as an ion detector in the low energy particle instrument onboard the GEOTAIL satellite.

A microchannel plate (MCP) assembly has been used as an ion detector in the low energy particle (LEP) instrument onboard the magnetospheric satellite GEOTAIL. Recently the MCP assembly has detected gamma rays emitted from an astronomical object and has been shown to provide unique information of gamma rays if they are intense enough. However, the detection efficiency for gamma rays was not measured before launch, and therefore we could not analyze the LEP data quantitatively. In this article, we report the gamma-ray detection efficiency of the MCP assembly. The measured efficiencies are 1.29%+/-0.71% and 0.21%+/-0.14% for normal incidence 60 and 662 keV gamma rays, respectively. The incident angle dependence is also presented. Our calibration is crucial to study high energy astrophysical phenomena by using the LEP.

Serum pepsinogen can predict response to H2-receptor antagonist in patients with functional dyspepsia.

BACKGROUND: Therapy for the relief of symptoms of functional dyspepsia is unpredictable. AIM: To identify which patients may benefit from antisecretory therapy. METHODS: Twenty-seven patients with functional dyspepsia were selected to receive H2-receptor antagonist (H2RA) treatment for 4 weeks. Serum pepsinogen A, pepsinogen C and gastrin were measured, and Helicobacter pylori status was determined. Symptoms were assessed at baseline and after H2RA treatment. RESULTS: Fourteen patients were identified as H2RA responders and the remaining patients were non-responders. No differences were found between responders and non-responders with regard to serum pepsinogen A, pepsinogen C, gastrin and H. pylori status. However, the pepsinogen A/C ratio was significantly higher in responders than in non-responders. Ten of the 13 functional dyspepsia patients (77%) with a high value of the pepsinogen A/C ratio (> or = 4.5) achieved symptom resolution by H2RA, compared with only one of the eight patients (13%) with a low value of the pepsinogen A/C ratio (< or = 3.0). CONCLUSIONS: The serum pepsinogen A/C ratio seems to identify those functional dyspepsia patients for whom acid control provides benefit. This ratio may be a practical tool for the management of functional dyspepsia patients.

Glutamine synthetase gene expression at elevated hydrostatic pressure in a deep-sea piezophilic Shewanella violacea.

A glutamine synthetase gene (glnA) was isolated from a deep-sea piezophilic bacterium, Shewanella violacea strain DSS12. A 7.5-kb SacI fragment containing the complete glnA gene was cloned and sequenced. The glnA gene was found to encode a protein consisting of 469 amino acid residues, showing 75.0% identity to the glutamine synthetase of Escherichia coli. Primer extension analyses revealed two transcription initiation sites in glnA and expression from each site was positively regulated by pressure. Putative promoters recognized by sigma(70) and sigma(54) were identified in the region upstream of glnA. An electrophoretic mobility shift assay demonstrated that S. violacea sigma(54) specifically binds to the promoter region of glnA, suggesting that sigma(54) may play an important role in pressure-regulated transcription in this piezophilic bacterium.

Design, fabrication, and properties of macroscale supramolecular fibers consisted of fully hydrogen-bonded pseudo-polymer chains.

Macro-scale supramolecular fibers composed of hydrogen bonded pseudo-polymer chains of guanosine derivatives were fibricated, and physical properties of the fibers were investigated.

Cronkhite-Canada syndrome: report of two cases.

Two cases of Cronkhite-Canada syndrome are reported. In the first case, a 56-year-old woman had an adenoma of the colon, arising within the Cronkhite-Canada polyps, which was removed by endoscopic polypectomy. This suggests possible neoplastic transformation of polyps in this syndrome. She achieved remission with corticosteroids, but the polyposis recurred (only in the stomach) 7 months after the remission. In the recurrent polyposis, corticosteroid therapy resulted again in complete remission, which has lasted for 5 years. In the second case, a 69-year-old man developed typical manifestations of the syndrome while under emotional stress. He had a past history of chronic pityriasis lichenoides, and serum antinuclear antibody was positive. These findings suggested a possible role of autoimmune response in the pathogenesis of the syndrome. Corticosteroids were also effective in this patient.

Varioliform gastritis and duodenitis associated with protein-losing gastroenteropathy, treated with omeprazole.

A 44-year-old female with varioliform gastritis and duodenitis had gastrointestinal protein loss revealed by 111indium chloride scintigraphy. Treatment with omeprazole, a proton pump inhibitor, for 2 months, followed by famotidine, resulted in clinical improvement with resolution of the gastroduodenal lesions and protein loss. Colonization of the stomach with Helicobacter pylori was found before and after the treatment. The results in this patient suggest that omeprazole can be of value for the treatment of varioliform gastritis associated with protein-losing gastroenteropathy. The role of Helicobacter pylori in the pathogenesis of this disease is unclear.

Multiple hepatic infarction after transcatheter arterial infusion with SMANCS.

We report a patient with hepatocellular carcinoma who developed multiple hepatic infarction after transcatheter arterial infusion (TAI) with a suspension of styrene maleic acid neocarzinostatin (SMANCS) and Lipiodol (SMANCS/Lipiodol). The parameters of hepatic functional reserve were apparently decreased after the second TAI with SMANCS/Lipiodol, and the patient died of hepatic failure 103 days after the second TAI. The autopsy liver specimen revealed multiple hepatic infarctions associated with peripheral arterial stenosis or occlusion, and portal thrombosis. It is speculated that both the arterial occlusion and the portal thrombosis caused the hepatic infarction, based on a long-term insufficiency of blood supply to the hepatocytes arising from toxic arteritis caused by SMANCS/Lipiodol.

Pericardiac metastasis from advanced gastric cancer.

A 64-year-old man complaining of anterior chest pain, weight loss, and neck tumors was found to have advanced gastric cancer with pleuritis carcinomatosa and multiple lymph node and bone metastases. The patient was treated with combination chemotherapy consisting of mitomycin C (MMC), tegafur (UFT), and lentinan, and then with MMC and 5-fluorouracil (5FU) instillation into the pleural spaces after pleural drainage. With these treatments, the primary tumors and cancerous ulcers of the stomach improved markedly, and the lymph node enlargement and pleural effusion disappeared completely. Afterwards pericardiac metastasis complicated by cardiac tamponade occurred, but repeated pericardiocentesis and administration of MMC into the pericardiac cavity effectively eliminated the effusion. These treatments appeared potentially useful for advanced gastric cancer with generalized metastases including pericardiac involvement. However, the patient died of cardiac tamponade with massive pericardiac bleeding, probably due to the repeated pericardiocentesis and/or the administration of anticancer drugs.

A case of mesenteric venous thrombosis after endoscopic variceal band ligation.

A rare case of isolated superior mesenteric venous thrombosis (MVT) after endoscopic variceal band ligation (EVL) is reported. A 64-year-old woman with a history of idiopathic portal hypertension presented at the emergency room with vomiting, increasing cramping abdominal pain, and low-grade fever. She had undergone EVL for esophageal varices 4 months before and had had intermittent attacks of mild abdominal pain after the EVL. Ultrasonogram of the abdomen demonstrated marked concentric wall thickening of the ileal loop. Enhanced computed tomographic (CT) scan revealed a central lucency in the lumen of the superior mesenteric vein, surrounded by a high-density vein wall, corresponding to a thrombus. An isolated MVT and venous collateral network in the splanchnic area were confirmed by angiography. Supportive therapy, i.e., water and electrolyte replacement, and anticoagulation improved the clinical condition and radiologic status. This case of MVT after EVL suggests a possible relationship between EVL and MVT. It is necessary for clinicians to be aware of this relationship for the early diagnosis of MVT.

Contribution of endothelin-1 to disruption of blood-brain barrier permeability in dogs.

We examined the effect of intracisternal application of endothelin-1 (ET-1) on the permeability of fluorescein into the cerebrospinal fluid (CSF) in beagle dogs in order to evaluate its role in disruption of blood-brain barrier (BBB) permeability seen in the subarachnoid hemorrhage animal model. Intracisternal application of their autologous blood for producing a canine two-hemorrhage model revealed an enhanced fluorescein permeability into the CSF together with the development of cerebral vasospasm. A single dose of ET-1 (40 pmol/animal) significantly increased penetration of fluorescein compared with that in normal dogs. Although its magnitude was much less than that in the two-hemorrhage model after the first administration of ET-1, the second challenge of the same dose of ET-1 with a 48-h interval produced marked disruption of BBB permeability similar to those in the animal model. Moreover, the ET-1-induced enhancement of fluorescein permeability into the CSF was completely prevented by intracisternal pretreatment with an endothelin ET(A)-receptor selective antagonist, S-0139 (0.03 mg/kg), as were the ET-1-induced cerebral vasoconstriction and behavioral changes as previously reported. Thus, we conclude that ET-1 acting on the adventitial site of brain in dogs contributes to the disruption of BBB permeability via endothelin ET(A)-receptor mediation.

The relative biological effectiveness of accelerated carbon ions with different LET for inducing mitotic crossing over and intragenic reversion of the white-ivory allele in Drosophila larvae.

PURPOSE: To evaluate the relative biological effectiveness (RBE) of accelerated carbon ions generated with a synchrotron for inducing mutations as a function of linear energy transfer (LET), using the loss of heterozygosity for wing-hair mutations and the reversion of the mutant white-ivory eye-colour in Drosophila melanogaster. MATERIALS AND METHODS: The measurements were made using a combined mutation assay system so that induced mutant wing-hair clones as well as revertant eye-colour clones can be detected simultaneously in the same fly. Larvae were irradiated at the age of 72+/-6 h post-oviposition with X-rays or carbon ions with LET values of 13, 60 and 95 keV/microm. RESULTS: The RBE of carbon ions for producing wing-hair mosaic spots increased with increasing LET values. The RBE for the induction of eye-colour mutants did not change with LET. The estimated RBE values were found to be in the range 2 to 6.5 for the wing-hair and nearly unity for the eye-colour mosaic spot mutations. CONCLUSIONS: RBE-LET relationships were obtained for the induction of wing-hair and eye-colour mosaic spots. These relationships suggest that more complex types of DNA damage, such as nonrejoinable strand breaks that increase with LET, may be responsible for inducing the wing-hair mutation, while more simple forms of molecular damage induce reversion in the white-ivory allele.

Distinct difference in relative biological effectiveness of 252Cf neutrons for the induction of mitotic crossing over and intragenic reversion of the white-ivory allele in Drosophila melanogaster.

The relative biological effectiveness (RBE) of 252Cf neutrons was determined for two different types of somatic mutations, i.e., loss heterozygosity for wing-hair mutations and reversion of the mutant white-ivory eye-color, in Drosophila melanogaster. Loss of heterozygosity for wing-hair mutations results predominantly from mitotic crossing over induced in wing anlage cells of larvae, while the reverse mutation of eye color is due to an intragenic structural change in the white locus on the X-chromosome. For a quantitative comparison of RBE values for these events, we have constructed a combined mutation assay system so that induced mutant wing-hair clones as well as revertant eye-color clones can be detected simultaneously in the same individuals. Larvae were irradiated at the age of 80 +/- 4 h post-oviposition with 252Cf neutrons or 137Cs gamma-rays, and male adult flies were examined under the microscope for the presence of the two types of clonal mosaic spots appearing. The induction of wing-hair spots per dose unit was much greater for 252Cf neutrons than for 137Cs gamma-rays, whereas the frequencies of eye-color reversion were similar for neutrons and gamma-rays. The estimated RBE values of neutrons were 8.5 and 1.2 for the induction of mutant wing-hair spots and revertant eye-color spots, respectively. These results indicate that the RBE of neutrons is much greater for mitotic crossing over in comparison to the intragenic white-ivory reversion events. Possible causes for the difference in RBE are discussed.

Generalized concept of the LET-RBE relationship of radiation-induced chromosome aberration and cell death.

The frequency of chromosome aberrations per traversal of a nucleus by a charged particle at the low dose limit increases proportionally to the square of the linear energy transfer (LET), peaks at about 100 keV/micron and then decreases with further increase of LET. This has long been interpreted as an excessive energy deposition over the necessary energy required to produce a biologically effective event. Here, we present an alternative interpretation. Cell traversed by a charged particle has certain probability to receive lethal damage leading to direct death. Such events may increase with an increase of LET and the number of charged particles traversing the cell. Assuming that the lethal damage is distributed according to a Poisson distribution, the probability that a cell has no such damage is expressed by e-cLx, where c is a constant, L is LET, and x is the number of charged particles traversing the cell. From these assumptions, the frequency of chromosome aberration in surviving cells can be described by Y = alpha SD + beta S2D2 with the empirical relation Y = alpha D + beta D2 in the low LET region, where S = e-cL, alpha is a value proportional to LET, beta is a constant, and D is the absorbed dose. This model readily explains the empirically established relationship between LET and relative biological effectiveness (RBE). The model can also be applied to clonogenic survival. If cells can survive and they have neither unstable chromosome aberrations nor other lethal damage, the LET-RBE relationship for clonogenic survival forms a humped curve. The relationship between LET and inactivation cross-section becomes proportional to the square of LET in the low LET region when the frequency of a directly lethal events is sufficiently smaller than unity, and the inactivation cross-section saturates to the cell nucleus cross-sectional area with an increase in LET in the high LET region.