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Seiichi Tanaka

Publications and source records attributed to Seiichi Tanaka.

15 recordsLinked to original sources
PubMed2006

Small-cell neuroendocrine carcinoma of the ampulla of Vater.

We report a patient (an 80-year-old woman) with anemia and fecal occult blood, who had an emergency operation for carcinoma of the cecum (well-differentiated adenocarcinoma without local lymph node metastasis). Postoperative magnetic resonance cholangiopancreatography, cholangiography, and upper gastroduodenal endoscopy showed a tumor of the ampulla of Vater, and pylorus-preserving pancreatoduodenectomy was performed. Histology of the resected tumor was that of small-cell carcinoma, and immunohistochemistry showed positive staining for neuron-specific enolase, chromogranin A, and synaptophysin, confirming the neuroendocrine nature of the tumor. As the histology of the tumor was distinct from cecal carcinoma, and no tumors were found in other organs, the tumor was diagnosed as primary small-cell neuroendocrine carcinoma of the ampulla of Vater. The patient died due to multiple liver metastases of the carcinoma of the ampulla of Vater 7 months after the pancreatoduodenectomy. The clinical and morphological features of this disease have been reported in nine individuals previously.

Adenocarcinoma↗
PubMed2005

A mother and a child with maternally inherited diabetes and deafness (MIDD) showing atrophy of the cerebrum, cerebellum and brainstem on magnetic resonance imaging (MRI).

A mother and a child with maternally inherited diabetes and deafness (MIDD) showing atrophy of the cerebrum, cerebellum and brainstem on magnetic resonance imaging (MRI) were reported. The proband had slowly progressive cerebellar ataxia and her son had depression. Mitochondrial DNA purified from their leucocytes had the heteroplasmic point mutation at position 3243 (A-->G). Involvement of the central nervous system should be considered in MIDD as well as in other mitochondrial diseases.

Adult↗
PubMed2005

[Second-line chemotherapy with bi-weekly CPT-11 and cisplatin for recurrent colorectal cancer resistant to 5-FU based chemotherapy].

Second-line chemotherapy with bi-weekly CPT-11 and cisplatin (CDDP) was given to 19 patients with recurrent colorectal cancer resistant to 5-FU based chemotherapy. The 19 patients consisted of 18 men and 1 woman with a mean age of 61.3 years. Nine patients had liver metastasis, 4 had lung metastasis, 2 had local recurrence, 2 had both local recurrence and lung metastasis, respectively, 1 had local metastasis and lymph node metastasis, and 1 had bone metastasis. CPT-11 (80 mg/m2) and CDDP (30 mg/m2) were administered bi-weekly. The objective overall response rate was 15.8%. The time to progression was 146 days, and the median survival time was 477 days. Grade 3 leucopenia and nausea occurred in 1 patient (5.3%). CPT-11 and CDDP treatment should be considered as second-line chemotherapy for colorectal cancer resistant to 5-FU based chemotherapy.

Adult↗
PubMed2004

Use of herpesvirus papio 2 as an alternative antigen in immunoblotting assay for B virus diagnosis.

Herpesvirus papio 2 (HVP2), which infects baboons, is much more closely related genetically and antigenically to monkey B virus (BV) than to human herpes simplex virus 1(HSV1) and other related herpes viruses. The usefulness of HVP2 as an alternative test antigen in immunoblotting assays to detect BV-antibody in macaque monkey sera was assessed. Six HVP2 proteins reacted with BV-positive sera in immunoblotting. No specific bands could be detected with BV-negative sera. These results show the usefulness of HVP2 antigen as an alternative and safer antigen than authentic BV antigen in detecting BV antibody in immunoblotting.

Animals↗
PubMed2004

Role of IL-6 and IL-1beta in reactivation by acetylcholine of latently infecting pseudorabies virus.

We previously reported that the latently infecting Pseudorabies virus (PrV) could be reactivated by injection of swine or mice with acetylcholine. However, the mechanism of the reactivation was not clear yet. In this study, we analyzed the kinetics of cytokines related to stress to clarify the relationship between virus reactivation by acetylcholine and the immune system. IL-6 and IL-1beta were detected in mice after stimulation with acetylcholine. This shows that acetylcholine induced physiological stress conditions. However, there seemed to be no relationship between the kinetics of the cytokine levels and PrV excretion. Moreover, neither IL-6 nor IL-1beta alone could reactivate latently infecting PrV. Thus, acetylcholine causes the reactivation of latent PrV via a mechanism not involving these immunological factors.

Acetylcholine↗
PubMed2004

[A case of recurrent gallbladder cancer responding to combination chemotherapy of TS-1 and CDDP].

A 76-year-old man suffering from advanced gallbladder cancer after hepato-pancreaticoduodenectomy had cholangitis and serum elevation of CA19-9 2 years and 6 months after the operation. A recurrent tumor had been recognized from the hilar to the surrounding inferior vena cava, and stenosis of jejunum utilized for pancreaticocholedoco-jejunostomy. A bypass operation of jejunum was performed. Combination chemotherapy with TS-1 100 mg/day (3 weeks) and CDDP 30 mg/day (day 1, 8 drip infusion) in 1 course was performed, and a partial response (PR) was noted. Diarrhea of grade III and decreased WBC of grade II were recognized, and were improved. Two courses of the same chemotherapeutic regimen were carried out. Among 5 months, recurrent tumor showed preservation of PR. Into 3 course of chemotherapy, radiation therapy was selected for second opinion. But recurrent tumor was enlarged acutely, and radiation therapy was stopped. He died 15 months after the first detection of chemotherapy. The combination chemotherapy of TS-1 and CDDP seems to be beneficial therapy for advanced gallbladder cancer.

Aged↗
PubMed2003

Effect of mild stress in mice latently infected pseudorabies virus.

Stress is one of the important factors that induces reactivation of pseudorabies virus (PrV) in latently infected pigs. We established a murine model of latent PrV infection and examined the effects of mild stress treatment in order to demonstrate that this model simulates natural infection in the pig. Latently infected mice excreted PrV from the nasal cavity under stress treatments consisting of restraint, exposure to cold or transport. Similar reactions have been observed upon treatment with acetylcholine and dexamethasone. The present findings demonstrate that these kinds of mild stress reactivate the virus in murine latent infection models in a manner similar to the induction of latent infection in pigs in the field.

Acetylcholine↗
PubMed2003

[Rabies virus].

Explore the source record for details and available documents.

Animals↗
PubMed2003

[A case of gastric cancer with multiple liver metastasis responding to combination therapy of CPT-11 and CDDP].

A 63-year-old man suffering from advanced gastric carcinoma after distal gastric resection had multiple liver metastases 5 months after the operation. He underwent 3 courses of combination chemotherapy of 5-FU 600 mg/day with CDDP 50 mg/day, etoposide 100 mg/day and Leucovorin 30 mg/day for 5 days (FLEP), but progressive disease (PD) was noted. One additional course of combination chemotherapy with CPT-11 140 mg/day and CDDP 40 mg/day biweekly was performed and a complete response (CR) was noted. After 4 months, recurrence of a liver metastasis on S8 was demonstrated and 2 courses of the same chemotherapeutic regimen were carried out. Over 5 months, recurrence of the liver metastasis showed no change (NC) and resection of S8 of the liver was performed. No recurrence was after 6 months, but the patient died 34 months after the first detection of the occurrence of multiple liver metastases. The combination chemotherapy of CPT-11 with CDDP was also administered to other patients at our outpatient clinic and seems to be useful therapy for improving outcome.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

Dehydroepiandrosterone (DHEA) as a possible source for estrogen formation in bone cells: correlation between bone mineral density and serum DHEA-sulfate concentration in postmenopausal women, and the presence of aromatase to be enhanced by 1,25-dihydroxyvitamin D3 in human osteoblasts.

A significant positive correlation between bone mineral density (BMD) and serum dehydroepiandrosterone sulfate (DHEA-S) was found in 120 postmenopausal women (51-99 years old) but no correlation was seen between BMD and serum estradiol. In subset analysis, strong positive correlation of serum DHEA-S and estrone with BMD was observed in postmenopausal women aged less than 69 years old. To study a possible role of DHEA-S in preventing osteoporosis, we characterized aromatase activity converting androgens to estrogens in human osteoblasts, because postmenopausal women maintain considerable levels of adrenal androgens. Glucocorticoids at 10(-9) to 10(-7) M induced transiently the expression of and the enzymatic activity of aromatase cytochrome P450 (P450AROM) in primary cultured osteoblasts. 1,25-Dihydroxyvitamin D3 (1,25-(OH)(2)D(3)) alone did not induce the aromatase activity, but enhanced and maintained the glucocorticoid-induced P450AROM gene expression. Analysis of the activity of P450AROM gene 1b (I.4) promoter, which is used dominantly in human osteoblasts, indicated that the region from -888 bp to -500 bp, which does not contain a typical vitamin D responsive element, is responsible for the enhancing effect of 1,25-(OH)(2)D(3). These results may suggest that adrenal androgen, DHEA, is converted to estrone in osteoblast by P450AROM, which is positively regulated by glucocorticoid and 1,25-(OH)(2)D(3), and is important in maintaining BMD in the sixth to the seventh decade, after menopause.

24,25-Dihydroxyvitamin D 3↗
PubMed2002

Genetic analysis of rabies virus isolates in the Philippines.

To determine the genetic characteristics of the rabies virus in the Philippines, 59 rabies virus isolates were obtained from domestic rabid dogs and their partial nucleotide sequences of nucleoprotein (N) gene were compared. Based on comparison with reported sequences, phylogenetic analysis revealed that all isolates from the Philippines had close genetic relations and formed two subgroups. The Philippines isolates belonged to a different lineage from other Asian isolates but were closer to them than to terrestrial isolates and laboratory strains. Several specific nucleotide and amino acid substitutions were observed among the Philippines isolates. Our results suggest that rabies viruses in the Philippines might have a characteristic evolution.

Amino Acid Sequence↗
PubMed2002

Identification of immunodominant neutralizing epitopes on the hemagglutinin protein of rinderpest virus.

The immunodominant epitopes on the hemagglutinin protein of rinderpest virus (RPV-H) were determined by analyzing selected monoclonal antibody (MAb)-resistant mutants and estimating the level of antibody against each epitope in five RPV-infected rabbits with the competitive enzyme-linked immunosorbent assay (c-ELISA). Six neutralizing epitopes were identified, at residues 474 (epitope A), 243 (B), 548 to 551 (D), 587 to 592 (E), 310 to 313 (G), and 383 to 387 (H), from the data on the amino acid substitutions of hemagglutinin protein of MAb-resistant mutants and the reactivities of MAbs against RPV-H to the other morbilliviruses. The epitopes identified in this study are all positioned on the loop of the propeller-like structure in a hypothetical three-dimensional model of RPV-H (J. P. M. Langedijk et al., J. Virol. 71:6155-6167, 1997). Polyclonal sera obtained from five rabbits infected experimentally with RPV were examined by c-ELISA using a biotinylated MAb against each epitope as a competitor. Although these rabbit sera hardly blocked binding of each MAb to epitopes A and B, they moderately blocked binding of each MAb to epitopes G and D and strongly blocked binding of each MAb to epitopes E and H. These results suggest that epitopes at residues 383 to 387 and 587 to 592 may be immunodominant in humoral immunity to RPV infection.

Amino Acid Sequence↗
PubMedDate not supplied

Mucosa-associated lymphoid tissue-type lymphoproliferative lesion of the common bile duct.

Only a few cases of primary lymphoma of the common bile duct have been reported up to now. Here, we report a mucosa-associated lymphoid tissue (MALT)-type lymphoproliferative lesion of the common bile duct with some considerations about MALT lymphoma and benign lymphoproliferation. The patient, a 71-year-old woman, was admitted to our hospital because of progressive epigastric pain. Abdominal ultrasonography, magnetic resonance cholangiopancreatography, endoscopic retrograde cholangiopancreatography, and abdominal computed tomography showed a non-specific finding of stenosis of the common bile duct due to thickening of the wall. Angiography provided little diagnostic information. Bile duct carcinoma was diagnosed and pylorus-preserving pancreaticoduodenectomy was performed. Histological examination revealed that the common bile duct was occupied by full-thickness proliferation of lymphoplasma cells with many reactive lymph follicles. The histological features were somewhat consistent with those of MALT lymphoma. However, we could not determine the clonal proliferation of lymphoplasma cells in either immunohistochemical immunoglobulin light chain restriction of the plasma cells or in polymerase chain reaction based immunoglobulin heavy chain gene rearrangement. The present case may be categorized as a borderline lesion close to benign lymphoproliferation. To the best of our knowledge, there have been no reports of cases similar to the present case.

Aged↗