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T Kan

Publications and source records attributed to T Kan.

At least 19 recordsLinked to original sources
PubMed2006

Transcriptional profiling suggests that Barrett's metaplasia is an early intermediate stage in esophageal adenocarcinogenesis.

To investigate the relationship between Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC), we determined gene expression profiles of discrete pathological stages of esophageal neoplasia using a sequence-verified human cDNA microarray. Fifty one RNAs, comprising 24 normal esophagi (NE), 18 BEs, and nine EACs were hybridized to cDNA microarrays. Five statistical analyses were used for the data analysis. Genes showing significantly different expression levels among the three sample groups were identified. Genes were grouped into functional categories based on the Gene Ontology Consortium. Surprisingly, the expression pattern of BE was significantly more similar to EAC than to NE, notwithstanding the known histopathologic differences between BE and EAC. The pattern of NE was clearly distinct from that of EAC. Thirty-six genes were the most differentially modulated, according to these microarray data, in BE-associated neoplastic progression. Twelve genes were significantly differentially expressed in cancer-associated BE's plus EAC (as a single combined tissue group) vs noncancer-associated BE's. These genes represent potential biomarkers to diagnose EAC at its early stages. Our results demonstrate that molecular events at the transcriptional level in BE are remarkably similar to BE's-associated adenocarcinoma of the esophagus. This finding alarmingly implies that BE is biologically closer to cancer than to normal esophagus, and that the cancer risk of BE is perhaps higher than we had imagined. These findings suggest that changes modulated at the molecular biologic level supervene earlier than histologic changes, and that BE is an early intermediate stage in the process of EAC.

Adenocarcinoma↗
PubMed2004

[Extrapleural pneumonectomy for malignant pleural mesothelioma].

Standard treatment for malignant pleural mesothelioma (MPM) has not been proved yet. However, it has been recognized that extrapleural pneumonectomy (EPP) is a treatment of choice for epithelial MPM when combined with adjuvant therapies though EPP may frequently cause fetal complications. We report 5 cases of MPM with EPP, including 1 with good prognosis. Sixteen patients with MPM were admitted to our hospital between 1988 and 2003. Five patients underwent EPP, among which 4 were male and 1 female with ages from 46 to 61 years old. Histologically, 3 of them were epithelial and 2 were biphasic. Those with biphasic experienced acute respiratory failure and empyema, and died 81 days and 8 months after the surgery respectively. Among those with epithelial MPM, 2 are alive with no recurrence at 129 and 29 months after the surgery, and the other, followed by postoperative radiotherapy, died at 12 months. More cases with EPP or randomized controlled trials regarding EPP are necessary to evaluate efficacy of EPP for MPM.

Female↗
PubMed2003

Validity of intraoperative pathological diagnosis of paratracheal lymph node as a strategy for selection of patients for cervical lymph node dissection during esophagectomy.

The aim of this paper is to examine whether intraoperative examination of paratracheal nodes can indicate cervical node dissection and whether this approach is valid. From 1988 to 1997, 76 patients with thoracic esophageal squamous cell carcinoma received esophagectomies with and without cervical lymph node (LN) dissection based on the results of intraoperative pathological diagnosis from selective checking of paratracheal LN. We retrospectively examined the outcomes for the patients and the micro metastasis in the dissected lymph node using cytokeratin staining. Three of the seven patients with cervical LN dissection were detected as having cervical LN metastasis by postoperative hematoxylin-eosin or cytokeratin staining. Five (7%) of the 69 patients without cervical LN dissection had cervical LN recurrence after the operation. Four of the seven patients who were diagnosed as having metastasis or micro metastasis in paratracheal LN by postoperative examination had cervical LN recurrence after the operation. In conclusion, the esophagectomy with and without cervical LN dissection for thoracic esophageal squamous cell carcinoma based on the results of intraoperative pathological diagnosis from selective checking of paratracheal LN was not fully acceptable. The reliability of intraoperative pathological diagnosis of selective checking may improve by increasing the number of checked LN and the detection of micro metastasis.

Aged↗
PubMed2001

Gene expression profiling in human esophageal cancers using cDNA microarray.

Human esophageal cancer cell lines and human esophageal cancer tissues were profiled on cDNA microarrays. In esophageal cancer cell lines, KYAE and OE-33 (adenocarcinomas) were distinguished from KYSE series (squamous cell carcinomas). Although SK-GT-4 and TE7 were derived from adenocarcinomas, they had a comparatively similar expression profile to the KYSE series. A set of genes whose expression commonly either increased or decreased in cancer cell lines was identified. Genes that were characteristically expressed in KYAE and OE-33 were also identified. The gene expression profiles of cancer tissues (CTs) were remarkably different from those of the cancer cell lines (CCLs). Notable differences between CCLs and CTs were observed in matrix metalloproteinases, plasminogen activator, collagens, paxillin, and thrombospondin 2, etc., whose expression was not increased in CCLs but increased in CTs. Twenty-three genes were extracted to categorize patients according to their prognoses, and clustering analyses, using these genes, were performed successfully.

Adenocarcinoma↗
PubMed2001

[A case of lung cancer underwent carinal resection with right upper lobectomy and carinal reconstruction with double-barreled anastomosis].

A 70-year-old male complaining cough was admitted to our hospital. Bronchoscopic examination revealed a tumor mass which occluded the orifice of the right upper lobe. Chest computed tomographic (CT) scans gave the image of tumor invasion at the carina. The pathological diagnosis of the tumor was squamous cell carcinoma. Operation was accomplished by right posterolateral thoracotomy approach through the fifth rib bed. The carinal resection with right upper lobectomy was followed by a double-barreled anastomosis of the right intermediate trunk and left main-stem bronchus into the carina. The operation was successfully performed and was considered curative. The length of resected airway measured 4.0 cm from tracheal line of resection to the divided the right intermediate trunk. Reinforcement of the anastomosis was not performed in this case. No postoperative complication occurred but mild ischemia of the anastomosis. The patient died of recurrent tumor in a year and 2 months after operation.

Aged↗
PubMed2001

[Is the bronchoscopic criteria of early lung cancer valid?].

We studied the validity of the bronchoscopic criteria of the early lung cancer using the surgical specimen excised between 1980 and 1999. Twenty-four cases with squamous cell carcinoma of the lung of clinical stage I were located subsegmental or more proximal bronchi and trachea, and the size less than 20 mm in greatest dimension. We histopathologically investigated the endoscopic features in relation to the width of superficial extent, the depth of cancer invasion, and lymph node metastasis. Tumors of the thickened type lesions less than 20 mm in greatest dimension showed no invasion into the cartilaginous layer and no lymph node metastasis. On the other hand, in the nodular and polypoid types, invasion beyond the cartilaginous layer was observed more or less, and lymph node metastasis was observed in 1 case. These cases would not be suitable for bronchoscopic (photodynamic) therapy. In conclusion, the bronchoscopic criteria of early lung cancer is valid in the thickened type, but not in the nodular type or polypoid type.

Aged↗
PubMed2000

Hydroxy-Directed, SmI(2)-Induced Conversion of Carbohydrates into Carbocycles.

Polyoxygenated six-membered carbocycles were derived from carbohydrates with complete stereocontrol through hydroxy-directed coupling cyclization induced by SmI(2). For example, the cis-1,3-cyclohexanediol 3 is obtained from the D-glucopyranoside derivative 1 in excellent yield. The coupling cyclization is initiated by single-electron transfer from SmI(2) to the formyl group of the delta-hydroxy aldehyde 2 generated in an equilibrium process.

Journal Article↗
PubMed2000

Total synthesis of polyamine toxin HO-416b and Agel-489 using a 2-nitrobenzenesulfonamide strategy.

Total synthesis of spider toxins HO-416b (1) and Agel-489 (2) was accomplished using the 2-nitrobenzenesulfonamide (Ns) group as both a protecting and activating group. In this strategy, the C-N bonds were constructed by alkylation of sulfonamides with alkyl halides or Mitsunobu reaction with the corresponding alcohol. Beginning with monoprotection of the symmetrical diamine, the construction of the backbone from diamine 3 was efficiently accomplished in 7 steps for 14 and 9 steps for 29. Removal of the Ns group while the substrate was attached to a novel solid support enabled the efficient isolation of this highly polar compound.

Indoles↗
PubMed2000

[Validity and controversies in the new postoperative pathologic TNM classification based on the results of surgical treatment of non-small cell lung cancer].

In 1997, the latest revision of the International System for Staging Lung Cancer was published. To validate the new pathologic TNM classification for non-small cell lung cancer (NSCLC), we analyzed the survival data of 455 patients who underwent pulmonary resection and pathologic staging at our institution from January 1980 through December 1999. The overall 5-year survival rate was 51.0%. Using the revised new stage classification, the survival rate for each stage was as follows; IA: 74.2%, IB: 66.4%, IIA: 56.0%, IIB: 51.8%, IIIA: 21.0%, IIIB: 16.0%, and IV: 0%. The current TNM classification well reflected the long-term prognostic hierarchy. There were significant differences in survival rates between patients with stage IA and IB, and between patients with stage IIB and IIIA. However, there was no significant difference between patients with stage IIA and IIB. No significant difference in survival was observed among patients with stage IIIA, stage IIIB, and stage IV. Five-year survival rate of 48.3% in the T3N0M0 category was significantly better than that of 21.0% found in the new stage IIIA. The survival of patients with intrapulmonary metastases in the same lobe (pm1) was not significantly better than that found in the stage IV. The TNM staging system accurately reflects the prognosis in NSCLC, but some stage definitions can be discussed.

Adolescent↗
PubMed1998

hobo Induced rearrangements in the yellow locus influence the insulation effect of the gypsy su(Hw)-binding region in Drosophila melanogaster.

The su(Hw) protein is responsible for the insulation mediated by the su(Hw)-binding region present in the gypsy retrotransposon. In the y2 mutant, su(Hw) protein partially inhibits yellow transcription by repressing the function of transcriptional enhancers located distally from the yellow promoter with respect to gypsy. y2 mutation derivatives have been induced by the insertion of two hobo copies on the both sides of gypsy: into the yellow intron and into the 5' regulatory region upstream of the wing and body enhancers. The hobo elements have the same structure and orientation, opposite to the direction of yellow transcription. In the sequence context, where two copies of hobo are separated by the su(Hw)-binding region, hobo-dependent rearrangements are frequently associated with duplications of the region between the hobo elements. Duplication of the su(Hw)-binding region strongly inhibits the insulation of the yellow promoter separated from the body and wing enhancers by gypsy. These results provide a better insight into mechanisms by which the su(Hw)-binding region affects the enhancer function.

Animals↗
PubMed1997

Anti-allergic effect of tea-leaf saponin (TLS) from tea leaves (Camellia sinensis var. sinensis).

We investigated the anti-allergic effect of tea-leaf saponin (TLS), which was a mixture of saponins separated from the leaves of Camellia sinensis var. sinensis, in guinea pigs and rats. TLS (20-100 mg/kg) dose-dependently inhibited experimentally-induced asthma, and ID50 was 61.7 mg/kg. TLS (20-100 mg/kg) dose-dependently inhibited a 48 h homologous PCA (passive cutaneous anaphylaxis) reaction, and the inhibitory effect was similar to that of tranilast. TLS (1-100 microg/ml) also inhibited the release of antigen-induced leukotriene (LT) C4 from sensitized guinea pig lung samples in a dose-dependent fashion, but did not prevent histamine release. TLS (0.01-0.5 microg/ml) inhibited histamine release from rat peritoneal mast cells induced by compound 48/80. At higher concentrations, TLS elicited histamine release. These findings suggest that TLS may be a useful protective agent against clinical allergy, and that the inhibitory effects of TLS on mediator release are in some way related to its inhibitory effect on experimentally-induced asthma and PCA reaction.

Airway Resistance↗
PubMed1995

[A case of gastric cancer developed in the gastric tube 11 years after subtotal esophagectomy for esophageal cancer].

A case of adenocarcinoma developed in the reconstructed gastric tube after esophagectomy was reported. The patient was 66 years old man and he had received subtotal esophagectomy for the carcinoma of the esophagus 11 years previously. The follow-up examination of upper GI series revealed an ulcerative lesion in the lower part of the gastric tube and endoscopic biopsy showed adenocarcinoma. The partial resection of the lower gastric tube with mediansternotomy was performed because of limiting the invasion of the carcinoma. Pathological examination showed that poorly differentiated adenocarcinoma with signet ring cells had invaded muscularis propria. The postoperative course was uneventful and he is well without any recurrence 6 months after the operation. A double carcinoma, such as esophageal cancer concomitant gastric cancer is not rare, but a carcinoma of the gastric tube which was substituted for the esophagus is rare. Recently, the incidence of carcinoma of the gastric tube is increasing due to the increasingly long-term survival rate of patients who had esophageal carcinoma. In order to ensure the early detection of a second carcinoma which can minimalize damage from curative resections, follow up examinations should be conducted with the utmost diligence.

Adenocarcinoma↗
PubMed1995

Inhibitory effect of epinastine on superoxide generation by rat neutrophils.

We studied the effects of antiallergic drugs, epinastine, ketotifen, oxatomide, mequitazine and cromolyn sodium on superoxide anion (O2-) generation from rat neutrophils. Epinastine, ketotifen, oxatomide and mequitazine dose-dependently prevented the N-formyl-Met-Leu-Phe- and phorbol 12-myristate 13-acetate-induced O2- generation, but cromolyn sodium did not prevent it. When membrane and cytosol fractions were incubated with each drug, epinastine, ketotifen and mequitazine prevented O2- generation. On the other hand, when only the membrane fraction was incubated with each drug, ketotifen and mequitazine prevented O2- generation, but epinastine did not. Epinastine may inhibit the NADPH oxidase system through the obstruction of NADPH oxidase-associated cytosol components.

Animals↗
PubMed1995

The influence of Helicobacter pylori infection on the progression of gastric mucosal atrophy and occurrence of gastric cancer.

AIM: To study the effects of Helicobacter pylori infection on the progression of gastric mucosal atrophy and the development of gastric cancer. PATIENTS AND METHODS: We investigated the extension of the atrophic area as assessed on the basis of the Kimura-Takemoto atrophic patterns and the development of gastric cancer in a selected sample of 64 patients who were endoscopically followed up for more than 3 years, and who showed H. pylori infection by culture at the start of the investigation and at some stages during the follow-up. RESULTS: No progression of atrophy was observed in 14 patients who were H. pylori-negative at the beginning of the follow-up, whereas various degrees of expansion of the atrophic area were found in 22% of 50 positive cases. Well differentiated mucosal cancer was diagnosed in four patients during the follow-up. These patients displayed moderate to severe atrophy. At the beginning of the follow-up, 50% of patients were H. pylori culture-positive, but all patients had H. pylori antibodies in their blood. CONCLUSIONS: The results support the view that H. pylori infection influences the development of atrophic gastritis and is related to the pathogenesis of gastric cancer.

Adult↗
PubMed1994

Superoxide anion-induced histamine release from rat peritoneal mast cells.

We investigated the properties of superoxide anion (O2-)-induced histamine release from rat peritoneal mast cells using superoxide anion radicals obtained from potassium superoxide (KO2). KO2 elicited a rapid histamine release in a dose-dependent fashion, without lactate dehydrogenase (LDH) release. The KO2-induced release was temperature- and energy-dependent. KO2 rapidly increased the intracellular free Ca2+ concentration, accompanied by a marked increase of Ca(2+)-uptake. These findings indicate that the increase in intracellular Ca2+ concentration is involved in the initiation of KO2-induced histamine release, and KO2 could be used as an agent of O2(-)-induced biological reactions.

Animals↗
PubMed1993

Effects of transgalactosylated disaccharides on the human intestinal microflora and their metabolism.

The effects of transgalactosylated disaccharide (TD) intake on human fecal microflora and their metabolism were investigated in 12 Japanese males. TD is a mixture of sugars, galactosyl galactose, and galactosyl glucose, synthesized from lactose through the transgalactosylation reaction of Streptococcus thermophilus beta-galactosidase. Volunteers took 15 g of the test sugar daily for 6 days. The TD ingestion increased the number of bifidobacteria and lactobacilli, but decreased the number of Bacteroidaceae and Candida spp. in the feces. The ratio of bifidobacteria to total bacteria increased from 0.28 to 0.51. TD decreased the fecal concentrations of propionic acid, isobutyric acid, isovaleric acid, and valeric acid. This sugar also lowered the fecal pH, and the concentrations of fecal ammonia, p-cresol, and indole. Moreover, a positive correlation was found between the concentration of ammonia, and that of branched-chain fatty acids (isobutyric acid and isovaleric acid), p-cresol, and indole. All of these compounds are produced from amino acids through deamination by the intestinal bacteria. The depression of amino acid fermentation by intestinal bacteria may be involved in the reduction of fecal ammonia. These results suggest that a part of the transgalactosylated disaccharides passes into the colon, inducing changes in the colonic microflora composition, hastening carbohydrate fermentation, and depressing amino acid fermentation in the human gut.

Adult↗
PubMed1993

[The effect of prostaglandin E1 and prostaglandin F2 alpha in the ischemic small intestine of dogs].

The effect of PGE1 and PGF2 alpha in the ischemic intestinal tract were examined. In 40 mongrel dogs, we studied ischemic models of small intestine. PGE1 or PGF2 alpha was injected into the anterior mesenteric artery after reperfusion according to each occlusion time, and the tissue blood flow was measured on both mucosal and serous sides of small intestinal loop by laser flowmeter to examine the relation to the extent of tissue damage. Tissue blood flow of the ischemic intestine after the injection of PGE1 increased by 148-208% in the 3-5 hr occlusion group and by 86-110% in the 7-10 hr occlusion group. Tissue blood flow after the injection of PGF2 alpha decreased by 39-59% in the 3-5 hr occlusion group and by 1-15% in the 7-10 hr occlusion group. These results indicate that the effect of PGE1 and PGF2 alpha in the ischemic intestine would be available up to 3-5 hr of ischemia. Histological examination revealed that viability of the remaining crypt was high in the PGE1 injection group but low in the PGF2 alpha injection group. These findings suggest that PGE1, if try at the early stage, would be effective for the treatment of ischemic lesion.

Alprostadil↗