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T Kodama

Publications and source records attributed to T Kodama.

At least 289 records · Page 16Linked to original sources
PubMed1998

Low-grade B cell lymphoma of mucosa-associated lymphoid tissue in the thymus of a patient with rheumatoid arthritis.

The majority of thymic lymphomas are either lymphoblastic lymphoma, large B cell lymphoma or Hodgkin's disease, and other types of non-Hodgkin lymphoma are rare. A case of low-grade B cell lymphoma of mucosa-associated lymphoid tissue (MALT) in the thymus is reported. A 55-year-old Japanese female with a history of rheumatoid arthritis (RA) complained of back pain. A mediastinal tumor was identified by computerized tomography and magnetic resonance imaging, and the thymus was resected through median sternotomy. The solid and nodular tumor had several small satellite extensions and was completely confined to within the thymus. Histologically, monotonous medium-sized centrocyte-like cells occupied the medulla of the thymus and infiltrated Hassall's corpuscles (lymphoepithelial lesions). Immunohistochemically, tumor cells were positive for CD20 and CD79a. IgA and kappa light chain restriction were also found in plasmacytoid cells in the tumor. Clonal rearrangement of the immunoglobulin heavy chain gene was demonstrated by polymerase chain reaction. This case was diagnosed as MALT-type low-grade B cell lymphoma in the thymus. This is the first report of low-grade B cell lymphoma in the thymus associated with RA. As autoimmune diseases are known to be associated with lymphoid neoplasms, it is suggested that the RA played an important role in the development of malignant lymphoma in this case.

Antigens, CD20↗
PubMed1998

A spore coat protein, CotS, of Bacillus subtilis is synthesized under the regulation of sigmaK and GerE during development and is located in the inner coat layer of spores.

The spore coat of Bacillus subtilis has a unique morphology and consists of polypeptides of different sizes, whose synthesis and assembly are precisely regulated by a cascade of transcription factors and regulatory proteins. We examined the factors that regulate cotS gene expression and CotS assembly into the coat layer of B. subtilis by Northern blot and Western blot analysis. Transcription of cotS mRNA was not detected in sporulating cells of sigmaK and gerE mutants by Northern blot analysis. By Western blot analysis using anti-CotS antibody, CotS was first detected in protein samples solubilized from wild-type cells at 5 h after the start of sporulation. CotS was not detected in the vegetative cells and spores of a gerE mutant or in the spores of mutants deficient in sigmaE, sigmaF, sigmaG, or sigmaK. CotS was detected in the sporangium but not in the spores of a cotE mutant. The sequence of the promoter region of cotS was similar to the consensus sequences for binding of sigmaK and GerE. These results demonstrate that sigmaK and GerE are required for cotS expression and that CotE is essential for the assembly of CotS in the coat. Immunoelectron microscopic observation using anti-CotS antibody revealed that CotS is located within the spore coat, in particular in the inner coats of dormant spores.

Amino Acid Sequence↗
PubMed1998

Comparison of four serological tests to determine the CagA or VacA status of Helicobacter pylori strains.

We compared four tests for antibodies to CagA or VacA, HelicoBlot 2. 0, RIDA Blot Helicobacter, CHIRON RIBA H. pylori SIA, and an enzyme-linked immunosorbent assay using recombinant CagA. Immunoblot assays were accurate for determining Helicobacter pylori status but poor for determining CagA or VacA status (accuracy, 66 to 80% for CagA status and 34 to 67% for VacA status). None can be recommended for determining CagA or VacA status.

Antigens, Bacterial↗
PubMed1998

Evaluation of a membrane filter assay system, Ortho HCV Ab Quick Pack, for detection of anti-hepatitis C virus antibody.

A simple membrane immunoassay assay system, Quik Pack, for the detection of hepatitis C virus antibody was compared with two enzyme-linked immunosorbent assays (ELISAs) in a study of 600 serum samples. Quik Pack exhibited excellent sensitivity and specificity: 96.0 and 99.7%, respectively, versus the ELISA-2 and 99.7 and 99.4%, respectively, versus the ELISA-3.

Enzyme-Linked Immunosorbent Assay↗
PubMed1998

Variants of the 3' region of the cagA gene in Helicobacter pylori isolates from patients with different H. pylori-associated diseases.

The CagA protein of Helicobacter pylori is an immunogenic antigen of variable size and unknown function that has been associated with increased virulence as well as two mutually exclusive diseases, duodenal ulcer and gastric carcinoma. The 3' region of the cagA gene contains repeated sequences. To determine whether there are structural changes in the 3' region of cagA that predict outcome of H. pylori infection, we examined 155 cagA gene-positive H. pylori isolates from Japanese patients including 50 patients with simple gastritis, 40 with gastric ulcer, 35 with duodenal ulcer, and 30 with gastric cancer. The 3' region of the cagA gene was amplified by PCR followed by sequencing. CagA proteins were detected by immunoblotting using a polyclonal antibody against recombinant CagA. One hundred forty-five strains yielded PCR products of 642 to 651 bp; 10 strains had products of 756 to 813 bp. The sequence of the 3' region of the cagA gene in Japan differs markedly from the primary sequence of cagA genes from Western isolates. Sequence analysis of the PCR products showed four types of primary gene structure (designated types A, B, C, and D) depending on the type and number of repeats. Six of the seven type C strains were found in patients with gastric cancer (P < 0.01 in comparison to noncancer patients). Comparison of type A and type C strains from patients with gastric cancer showed that type C was associated with higher levels of CagA antibody and more severe degrees of atrophy. Differences in cagA genotype may be useful for molecular epidemiology and may provide a marker for differences in virulence among cagA-positive H. pylori strains.

Adult↗
PubMed1998

Chemokines in the gastric mucosa in Helicobacter pylori infection.

BACKGROUND: Although chemokines have been suggested to play an important role in Helicobacter pylori associated gastritis, few studies have investigated the role of chemokines other than interleukin 8 (IL-8) in gastric mucosa. AIMS: To investigate the expression and production patterns of various chemokines using gastric biopsy specimens. METHODS: In 192 patients, expression patterns of C-X-C chemokines (IL-8 and growth regulated alpha (GRO alpha)) and C-C chemokines (regulated on activation, normal T cell expressed and presumably secreted (RANTES), monocyte chemotactic and activating factor (MCAF), macrophage inflammatory protein 1 alpha (MIP-1 alpha), and MIP-1 beta) were examined using reverse transcription polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay (ELISA). cagA gene was identified using PCR. RESULTS: H pylori infection was associated with increased rates of expression of mRNA for IL-8, GRO alpha, RANTES, and MIP-1 alpha and with increased levels of mucosal IL-8 and GRO alpha. IL-8 and GRO alpha levels correlated with the density of H pylori in both the antrum and corpus. The levels of these chemokines correlated with cellular infiltration in the antrum but not the corpus. cagA gene positive H pylori infection was associated with increased rates of expression of mRNA for IL-8 and GRO alpha and with increased levels of these chemokines. CONCLUSION: H pylori infection is associated with increased expression rates and production of C-X-C chemokines (IL-8 and GRO alpha), but not with increased production of C-C chemokines. Although H pylori infection is associated with increased C-X-C chemokines in the antrum and corpus, there is a difference in the inflammatory response between these two areas of the stomach.

Adult↗
PubMed1998

Characterization of two Chinese hamster ovary cell lines expressing the COOH-terminal domains of sterol regulatory element-binding protein (SREBP)-1.

Sterol regulatory element-binding proteins (SREBPs) regulate transcription of genes encoding enzymes in the cholesterol biosynthetic pathway and the LDL receptor. These proteins are synthesized as membrane-bound precursors and processed to generate the NH2-terminal domains, mature transcription factors. We established two Chinese hamster ovary (CHO) cell lines, CHO-421 expressing the truncated hamster SREBP-1 (amino acids 421-1133) with two transmenbrane domains and CHO-557 expressing another truncated SREBP-1 (amino acids 557-1133) without any transmembrane domains, to investigate the fate of the COOH terminus after cleavage of the NH2-terminal mature SREBP. The cell fractionation experiments revealed that the two proteins, regardless of the absence of transmembrane domains in the SREBP (557-1133), similarly localized in the nuclear envelope and the microsomal membrane fractions, suggesting that these proteins appear to be tightly bound to a membrane protein(s) localizing on the nuclear and endoplasmic reticulum (ER) membranes. Although we predicted that overexpression of the COOH-terminal domains, which were thought to be involved in the regulation of SREBP processing, would result in disruption of the SREBP-dependent transcriptional regulation of several genes, the mRNA levels for 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) synthase in these two cell lines were regulated in a sterol-dependent manner. Pulse-chase experiments revealed that the SREBP (421-1133) was relatively rapidly degraded (t1/2 = 4-6 hr) and that the intracellular cholesterol level did not affect the half-life time. The degradation of the SREBP (421-1133) was not suppressed by the treatment of a calpain inhibitor, N-acetyl-leucyl-leucyl-norleucynal (ALLN), which blocks the proteolysis of some proteins within or near the ER. In CHO-557 cells the SREBP (557-1133) was much more rapidly degraded (t1/2 = 1-2 hr), suggesting that the cytosolic COOH-terminal domain is accessible to the enzymatic attacks from the cytoplasm. Taken together, overexpression of the COOH-terminal domains does not affect the regulation of SREBP processing and the domains are rapidly turned over by the cytosolic proteolytic process distinct from the ALLN-sensitive ER degradative pathway.

Animals↗
PubMed1998

Irsogladine maleate may preserve gastric mucosal hydrophobicity against ethanol in phospholipids independent way in rats.

Irsogladine maleate (IM) has been used as a mucosal protective agent, whose action is partially explained as enhancement of mucosal blood flow, increase of cellular cyclic AMP and facilitation of gap-junctional intercellular communication. Effect of IM on rat gastric mucosal hydrophobicity, one of the mucosal barrier properties, was investigated, in comparison with that of 16,16-dimethyl prostaglandin E2 (dmPGE2). IM alone had no effect on mucosal hydrophobicity and mucosal phospholipids content. dmPGE2 alone did not change mucosal hydrophobicity significantly, but remarkably increased mucosal surface-active phospholipids. Intragastric administration of absolute ethanol significantly decreased gastric mucosal hydrophobicity and mucosal phospholipids content. IM could prevent the decrease in mucosal hydrophobicity by ethanol, maintaining the surface mucus gel layer and mucosal surface phospholipids almost as non-damaged control levels, whereas dmPGE2 also prevented the decrease in mucosal hydrophobicity by ethanol, with the surface epithelium being partially exfoliated and mucosal surface-active phospholipids showing remarkable enhancement. These results suggest that IM may preserve gastric mucosal hydrophobicity against ethanol, not through enhancement of mucosal phospholipids content like prostaglandin, but possibly through its reported stabilization action to the epithelial cell lining, which may preserve the surface epithelium with the mucous gel layer containing surface-active phospholipids, a possible origin of mucosal hydrophobicity.

Animals↗
PubMed1998

The role of the nirQOP genes in energy conservation during anaerobic growth of Pseudomonas aeruginosa.

The nirQOP operon, which is located between the genes for nitrite reductase and nitric oxide reductase in Pseudomonas aeruginosa, encodes a putative ATP-binding protein and two putative transmembrane proteins. Phylogenetic analysis showed that NirO belongs to the family of subunit III of cytochrome oxidases but is distantly related to the other bacterial or mitochondrial proteins. P. aeruginosa strains that lacked the nirOP genes had all enzyme activities for denitrification and could grow under anaerobic conditions with nitrate or nitrite as an electron acceptor. However, the energy conservation efficiency of anaerobic respiration was lower in these strains than in strains harboring the nirOP gene.

Amino Acid Sequence↗
PubMed1998

Mediastinal germ cell tumor complicated by visceral hemangiomatosis.

This report describes an extremely rare combination of mediastinal germ cell tumor and visceral hemangiomatosis in a 17-year-old boy who initially presented with chest pain and dyspnea. He was treated with chemotherapy consisting of cisplatin, cyclophosphamide, bleomycin, vinblastine, and dactinomycin followed by surgery. Multiple low-density nodules developed in the spleen three weeks later, suggesting metastases from the primary tumor, but the resected specimen showed cavernous hemangiomas within the splenic parenchyma. The patient died of recurrence of germ cell tumor 19 months after the initial treatment. Postmortem examination disclosed multiple hemangiomas in the lung and liver similar to those in the spleen.

Adolescent↗
PubMed1998

Transsacral rectopexy for complete rectal prolapse.

A prospective study was carried out to analyze the clinical and functional results of transsacral rectopexy with a DEXON mesh in the elderly or poor risk patients with complete rectal prolapse. Six patients with complete rectal prolapse were operated from 1994 to 1996. All patients could be traced for examination with anorectal manometry and defecography. None of the patients had recurrence for the longest three years. In postoperative clinical symptoms, fecal incontinence score recovered from the preoperative mean score of 3.8 to the postoperative 1.2 and constipation was improved in 4 out of 5 cases (80.0%). Straining anorectal angle (S-ARA) by defecography improved from the preoperative value of 120.6 +/- 6.9 degrees to the postoperative value of 98.5 +/- 3.5 degrees (p < 0.05) and the perineal descent (PD) improved from the preoperative value of 16.2 +/- 2.5 cm to the postoperative value 8.1 +/- 1.3 cm (p < 0.05). Maximal resting pressure (MRP) increased from the preoperative value of 20.5 +/- 3.7 cmH2O to the postoperative value of 40.5 +/- 4.8 cmH2O (p < 0.05). Transsacral rectopexy with DEXON mesh for complete rectal prolapse is useful as this technique is simple to conduct, can be applied to the elderly or poor risk patients, replaces rectal prolapse, improves defecation troubles and recovers fecal incontinence.

Aged↗
PubMed1998

Intraductal ultrasonography for treatment of Tis and T1 colorectal cancer.

The aim of the study was to determine the treatment for Tis and T1 colorectal cancer and the depth of cancer invasion which was examined preoperatively by intraductal ultrasonography (IDUS) using a 20 MHz high frequency thin sonoprobe. IDUS was performed on 62 patients with Tis and T1 colorectal cancer using 20 MHz radial images. The tumors imaged by IDUS were classified into 3 groups according to the degree of lesions in the 5 layers of the large intestinal wall: Tis showing no changes in the third layer, T1 with slight invasion in which the ruptured region in the third layer occupied less than 50% of the tumor diameter, and T1 with massive invasion in which the ruptured region in the third layer occupied more than 50% of the tumor diameter. The correct preoperative diagnosis of the depth of the lesions was obtained in 21 of the 23 patients with Tis (91.3%), in 18 of the 21 patients with T1 with slight invasion (85.7%), and in 8 of the 11 patients with T1 with massive invasion (72.7%). In conclusion, IDUS can be used for endoscopic examination of the large intestinal cancer to judge whether local treatment or not.

Colonoscopy↗
PubMed1998

Endoscopic removal with clipping for colonic lipomas.

Endoscopic removal of colonic lipoma of 2 cm in size or more is not widely used because of the risk of complications which are a hemorrhage and a perforation associated with endoscopic resection. We report here safety endoscopic removal using a bipolar snare and clipping the mucosa of the defective region in three cases with large colonic lipoma. We consider that this technique enhanced the safety of the endoscopic procedure.

Aged↗
PubMed1998

Comparative epidemiology of cancers of the testis, lung, bladder and stomach with special reference to the possible implication of environmental hormones in the recent risk changes of the 4 neoplasia types.

The purpose of this study is to extract common features of an environmental hormone-oriented neoplasia by comparatively investigating the epidemiological characteristics of testicular cancer in Denmark with those of other cancers, of which the age-adjusted incidence rates (AAIRs) underwent remarkable increase or decrease in the time range of early 1960's to mid 1980's. Practically, the log-transformed (log) AAIRs and the corresponding log ASIRs (age-specific incidence rates) were used in parallel to investigate the dynamic aspect of cancer risk changes in time and space. The present study includes cancers of the testis, lung, bladder and stomach as study subjects, and followed the chronological transition of cancer risk for each tumor type and for each population unit from early 1960's to mid 1980's. In space, the present study includes the data for 6 population units as follows: Denmark, Birmingham-England, the State of New York less New York city, Miyagi-Japan, Puerto Rico and Cali-Colombia. Since 3 neoplasias other than testicular cancer were associated with male predominance of cancer risk, 1st order regression analysis was applied to a set of 5 chronologically consecutive data of log AAIRs for a given tumor to comparatively investigate the sex discrimination of cancer risk for each of 3 neoplasia types. Results obtained are as follows: a) the ASIR profile of testicular cancer in Denmark (a high-risk country) was a composite of an adult type surge and an infant type surge (a product of in utero carcinogenic insult). Consistent ascension of both the adult type surge and the infant type surge of the ASIR profile was observed in parallel with the straight line increase of log AAIR of testicular cancer in Denmark. b) The ASIR profiles of testicular cancer for Miyagi-Japan (a low-risk country with steady increase of log AAIR) experienced new emergence of the infant type surge that was detectable in the profile for the years 1968-1971 and 1983-1987, but not in the profile for the years 1959-1960. c) The ASIR profiles of testicular cancer for Cali-Colombia (a low-risk country with no sign of risk increase) was free of the infant type surge throughout the study period. d) Temporary emergence of the infant type surge was experienced in cancers of the lung and bladder in early 1970's. In space, the infant type surge had preference of occurrence for a high-risk country to a low-risk country, and for a male population to a female population. e) Another feature of environmental hormone-oriented tumor was found in the recent risk decrease of gastric cancer of which the rate of risk decrease was distinct in Western countries and Japan, but not in Cali-Colombia. Puerto Rico was ranked as an in-between existence--a violation to the rules of Westernization effect for cancer risk. f) The relation between the male log AAIR and the male log AAIR less female log AAIR for a given tumor type was found to have a good fitness to the equilibrium model of which the members are destined to interact with each other under the law of mass action. The above mathematical strictness was found to be valid with all of cancers of the liver, skin, lung, bladder, stomach and esophagus--a finding to indicate that the relation between the changes of male cancer risk and that of female cancer risk in time and space is defined by the law of mass action regardless of the presence or absence of environmental hormone impact, and that no marker is available to detect possible implication of the environmental hormones with this system. g) The significance of the last finding in cancer etiology was discussed in the light of the steroid criminal hypothesis of human carcinogenesis in general. In conclusion, the recent risk changes of cancers of all the testis, lung, bladder and stomach in high-risk areas are in part to be explained in terms of the environmental hormone impact.

Denmark↗
PubMed1998

Involvement of macrophage scavenger receptors in protection against murine malaria.

Macrophage scavenger receptor A (MSR-A) deficient mice MSR-A(-/-) were infected by the intraperitoneal injection of the Plasmodium berghei NK65 strain in the erythrocytic stage. The MSR-A(-/-) mice died significantly earlier than the control mice (P=0.060). In the surviving mice, two peaks of parasitemia were observed: the first 5-7 days and the second at 2-3 weeks after infection. Death of all MSR-A(-/-) mice occurred at either peak of parasitemia, suggesting that MSR-A protects mice from severe infection. This model may be useful for the study of molecular mechanisms of macrophage functions in malaria infection.

Animals↗
PubMed1998

[Thirteen-week intravenous repeated dose toxicity study of T-3762, a novel parenteral quinolone antimicrobial agent, and four-week recovery test in cynomolgus monkeys].

A thirteen-week intravenous repeated dose toxicity study of T-3762, parenteral quinolone antimicrobial agent, and four-week recovery test was carried out in male and female cynomolgus monkeys at dosages of 26, 52 and 104 mg/kg. The following results were obtained. 1) There was no death of animals during administration period at any dose levels. In general signs, there was no abnormality at any dose levels. 2) In appetite, body weights and ophthalmological examination, there was no abnormality attributable to the treatment. 3) In urinalysis, hematological examination and biochemical examination, there was no abnormality attributable to the treatment. 4) In organ weights, macroscopic findings and histopathological findings, there was no abnormality attributable to the treatment. 5) From these results in this study, no-toxic dose level of T-3762 for cynomolgus monkeys is considered over 104 mg/kg.

Animals↗
PubMed1998

[Reproductive and developmental toxicity study of T-3762 in rats administered intravenously during the period of organogenesis].

A teratogenicity study of T-3762, an injectable new quinolone antibacterial agent, was conducted in Sprague-Dawley rats to determine the effects on dams and next generations. T-3762 was administered intravenously to pregnant rats at the dose levels of 26, 78 and 156 mg/kg/day from day 7 to day 17 of gestation, during the organogenesis. 1. In the dams, there were no effects on general condition, food intake, water intake and body weight in the T-3762 treated groups. There were no abnormal findings on the autopsy at the end of gestation and lactation periods in the T-3762 treated groups. 2. In the fetuses, there were no effects on the number of dead and live fetuses, sex ratio and body weight in the T-3762 treated groups. No external, visceral and skeletal abnormalities attributed to T-3762 were observed. 3. In the offspring, there were no effects on birth rate, viability, differentiation of external development, body weight, sensory function, emotionality, learning ability and reproductive performance in the T-3762 treated groups. From these results, no-toxic dose levels of T-3762 are considered to be 156 mg/kg for the general toxicity and the reproductive toxicity of parents and for the development of next generation, respectively.

Animals↗