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Hideaki Nomura

Publications and source records attributed to Hideaki Nomura.

10 recordsLinked to original sources
PubMed2006

Successful resection of advanced pancreatic tail cancer after neoadjuvant gemcitabine chemotherapy: report of a case.

Pancreatic cancer with distant metastasis is not an indication for surgery, and the median survival of these patients is less than 3 months. We report the case of a patient who has survived for 21 months without any signs of recurrence after resection of advanced pancreatic cancer following a course of chemotherapy with gemcitabine (GEM). A 75-year-old man was hospitalized for anorexia and emaciation. Examinations showed pancreatic cancer with distant peritoneal metastasis. After the main tumor and metastasis had been shrunk by GEM chemotherapy, we performed distal pancreatectomy combined with splenectomy. Microscopically, the main tumor was confirmed as moderately differentiated tubular adenocarcinoma with interstitium and fibrosis. The radicality of the surgery was R0, according to the TNM classification of the UICC. The patient recovered well and has had no clinical symptoms for 40 months since the initial chemotherapy. This case suggests that multidisciplinary treatment with GEM may prolong the survival of some patients with unresectable pancreatic cancer.

Adenocarcinoma↗
PubMed2005

Microbial responses using denaturing gradient gel electrophoresis to oil and chemical dispersant in enclosed ecosystems.

Microbial responses to the addition of oil with or without a chemical dispersant were examined in mesocosm and microcosm experiments by using denaturing gradient gel electrophoresis of bacterial ribosomal DNA and direct cell counting. When a water-soluble fraction of oil was added to seawater, increases in cell density were observed in the first 24h, followed by a decrease in abundance and a change in bacterial species composition. After addition of an oil-dispersant mixture, increases in cell density and changes in community structure coincided, and the amount of bacteria remained high. These phenomena also occurred in response to addition of only dispersant. Our results suggest that the chemical dispersant may be used as a nutrient source by some bacterial groups and may directly or indirectly prevent the growth of other bacterial groups.

Bacteria↗
PubMed2003

Study on the fate of petroleum-derived polycyclic aromatic hydrocarbons (PAHs) and the effect of chemical dispersant using an enclosed ecosystem, mesocosm.

Polycyclic Aromatic Hydrocarbons (PAHs) are one of the components found in oil and are of interest because some are toxic. We studied the environmental fate of PAHs and the effects of chemical dispersants using experimental 500 l mesocosm tanks that mimic natural ecosystems. The tanks were filled with seawater spiked with the water-soluble fraction of heavy residual oil. Water samples and settling particles in the tanks were collected periodically and 38 PAH compounds were analyzed by gas chromatography-mass spectrometry (GC-MS). Low molecular weight (LMW) PAHs with less than three benzene rings disappeared rapidly, mostly within 2 days. On the other hand, high molecular weight (HMW) PAHs with more than four benzene rings remained in the water column for a longer time, up to 9 days. Also, significant portions (10-94%) of HMW PAHs settled to the bottom and were caught in the sediment trap. The addition of chemical dispersant accelerated dissolution and biodegradation of PAHs, especially HMW PAHs. The dispersant amplified the amounts of PAHs found in the water column. The amplification was the greater for the more hydrophobic PAHs, with an enrichment factor of up to six times. The increased PAHs resulting from dispersant use overwhelmed the normal degradation and, as a result, higher concentrations of PAHs were observed in water column throughout the experimental period. We conclude that the addition of the dispersant could increase the concentration of water column PAHs and thus increase the exposure and potential toxicity for organisms in the natural environment. By making more hydrocarbon material available to the water column, the application of dispersant reduced the settling of PAHs. For the tank with dispersant, only 6% of chrysene initially introduced was detected in the sediment trap whereas 70% was found in the trap in the tank without dispersant.

Accidents↗
PubMed2003

Study of the effect of water-soluble fractions of heavy-oil on coastal marine organisms using enclosed ecosystems, mesocosms.

Mesocosm facilities composed of 4 experimental and 2 reservoir tanks (1.5 m in diameter, 3.0 m in depth and 5 tons in capacity) made of FRP plastics, were constructed in the concrete fish rearing pond in the Fisheries Laboratory, The University of Tokyo. The water-soluble fraction of Rank A heavy residual oil was formed by mixing 500 g of the oil with 10 l of seawater, which was introduced to the 5000 l-capacity tanks. Experimental Run 4 was conducted from May 31 to June 7, 2000. Oil concentrations in the tanks were 4.5 microg/l called LOW, and 13.5 microg/l, called HIGH tank. Bacterial growth rates very quickly accelerated in the HIGH tank just after the loading of oil which corresponded with a high increase of bacterial cells in the same tank after 2 days. Later, bacterial numbers in HIGH tank rapidly decreased, corresponding with the rapid increase of heterotrophic nano-flagellates and virus numbers on the same day. Sediment traps were deployed at the bottom of the experimental tanks, and were periodically retrieved. These samples were observed both under light microscope and epi-fluorescent microscope with UV-excitation. It was observed that the main components of the vertical flux were amorphous suspended matter, mostly originating from dead phytoplankton and living diatoms. It was further observed from the pictures that vertical transport of oil emulsions were probably conducted after adsorption to amorphous suspended matter and living diatoms, and were settling in the sediment traps at the bottom of the tanks. This means that the main force which drives the soluble fraction of oil into bottom sediment would be vertical flux of such amorphous suspended particles and phytoplankton. Further incubation of the samples revealed that the oil emulsions were degraded by the activity of autochtonous bacteria in the sediment in aerobic condition.

Animals↗
PubMedDate not supplied

Laparoscopy-assisted colon resection for mucosa-associated lymphoid tissue (MALT) lymphoma in the cecum.

Colonic MALToma (mucosa-associated lymphoid tissue lymphoma) has not been well investigated compared to stomach MALToma which is related to Helicobacter pylori infection. We report the uncommon case of MALToma in the cecum initially identified as submucosal tumor, successfully treated by laparoscopy-assisted resection with systemic lymphadectomy. As the metastatic ability and sensitivity against chemotherapy of colonic MALToma is not known, temporally, this treatment seems to be the best choice.

Adult↗
PubMedDate not supplied

Hyperamylasemia after hepatic resection.

BACKGROUND/AIMS: Hyperamylasemia often occurs after hepatectomy, but the detailed mechanism of this phenomenon remains unclear. The aim of this study was to analyze factors that may be associated with the development of hyperamylasemia following hepatic resection. METHODOLOGY: The Pringle maneuver was performed in 12 patients (Pringle group), the hemihepatic vascular occlusion technique in 11 patients (Hemihepatic group). RESULTS: In the Pringle group, postoperative serum amylase levels were elevated significantly in comparison with the preoperative levels, but were not elevated in the hemihepatic group. CONCLUSIONS: It is suggested that portal congestion by portal triad interruption carries a potential risk of serum amylase elevation and pancreatitis after hepatectomy.

Adult↗
PubMedDate not supplied

Comparison of the functional and morphological changes in the pancreatic remnant between pylorus-preserving pancreatoduodenectomy and pancreatoduodenectomy.

BACKGROUND/AIMS: Pylorus-preserving pancreatoduodenectomy preserves the secretion of gastrointestinal hormones from the distal stomach and duodenum, whereas after pancreatoduodenectomy they are no longer secreted. It has been suggested that some gastrointestinal hormones exert a trophic effect on the pancreas, although this effect has not been documented in man. It was postulated that the ablation of gastrointestinal hormones, such as gastrin by pancreatoduodenectomy is an important cause of postoperative pancreatic atrophy and, since pylorus-preserving pancreatoduodenectomy preserves the secretion of these hormones, it would be more effective than pancreatoduodenectomy for the maintenance of postoperative pancreatic function. METHODOLOGY: We measured postoperative pancreatic function, parenchymal thickness of pancreas and the release of gastrin in patients who underwent pancreatoduodenectomy or pylorus-preserving pancreatoduodenectomy who had survived > 1 year without tumor recurrence. RESULTS: After pylorus-preserving pancreatoduodenectomy, exocrine pancreatic function, parenchymal thickness of pancreas and gastrin release were significantly greater than after pancreatoduodenectomy. CONCLUSIONS: We concluded that postoperative atrophy of the distal pancreas after pancreatoduodenectomy occurs, in part because of resections of the duodenum and distal stomach, which is the source of trophic stimuli, gastrin.

Ampulla of Vater↗
PubMedDate not supplied

Arterial hemorrhage by pseudoaneurysms following pancreatoduodenectomy.

Experienced centers report reduced operative mortality after pancreatoduodenectomy for cancer, but significant complications continue to occur in as many as 25% of patients. Anastomotic disruption leads to sepsis in the pancreatic bed where major vascular structures have been exposed by regional lymphadenectomy, creating a setting for arterial erosion or ligature slough and massive hemorrhage. Dehiscence of the pancreatojejunostomy is a particular risk. We presented one patient with arterial hemorrhage from visceral artery pseudoaneurysm after pancreatoduodenectomy, who had had sentinel bleeding from the abdominal drains or gastrointestinal tract. Sentinel bleeding after pancreatoduodenectomy indicates local sepsis and probable anastomotic dehiscence. Recognition of its significance and prompt response may prevent exsanguination.

Adenocarcinoma↗