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Biomedical subjects

H Takeyama

Publications and source records attributed to H Takeyama.

At least 37 records · Page 2Linked to original sources
PubMed2001

Isolation of Magnetospirillum magneticum AMB-1 mutants defective in bacterial magnetic particle synthesis by transposon mutagenesis.

Nonmagnetic mutants of Magnetospirillum magneticum AMB-1 were recovered following mini-Tn5 transposon mutagenesis. Transconjugants with kanamycin resistance were obtained at a frequency of 2.7 x 10(-7) per recipient. Of 3327 transconjugants, 62 were defective for bacterial magnetic particle (BMP) synthesis. The frequency of independent transposition events for nonmagnetic mutants was about 1.4% in transconjugants. Further analysis of DNA sequences flanking transposon by inverted polymerase chain reaction allowed isolation of at least 10 genes or DNA sequences involved in BMP synthesis in M. magneticum AMB-1.

Bacterial Proteins↗
PubMed2001

Synthesis of bacterial magnetic particles during cell cycle of Magnetospirillum magneticum AMB-1.

We investigated the relationship between the synthesis of bacterial magnetic particles (BMPs) and the transcription of magA gene-encoding iron transport protein using synchronous culture of Magnetospirillum magneticum AMB-1. Synchronously cultured cells were subjected to transmission electron microscopic observation and fluorescence in situ hybridization. The average number of BMPs slowly increased in the cell with increasing cell size. A sharp increase in BMPs occurred just before cell division and resulted in maximum BMP production of 30 particles/cell. The transcription of magA was regulated immediately before and after cell division.

Bacterial Proteins↗
PubMed2001

Pulmonary lymphoma of large B-cell type mimicking Wegener's granulomatosis.

A 27-year-old man with a primary pulmonary lymphoma of large B-cell type is described. Symptoms involved both the upper and lower respiratory tract. A chest roentgenogram showed a dense mass with cavitation. Transbronchial biopsy specimens revealed no atypical cells, rather they demonstrated granulomatous infiltration and vasculitis consistent with but not conclusively diagnostic of Wegener's granulomatosis. The pulmonary mass became smaller after sulfamethoxazole-trimethoprim therapy. These features suggested Wegener's granulomatosis. However, an open biopsy specimen was diagnostic for diffuse lymphoma of large B-cell type. High-grade pulmonary lymphoma should be considered in the differential diagnosis of patients with clinical and pathologic features suggesting Wegener's granulomatosis.

Adult↗
PubMed2001

Compound heterozygosity for alpha-1-antitrypsin (S(iiyama) and QO(clayton)) in an Oriental patient.

Alpha-1-antitrypsin (alpha1AT) deficiency is extremely rare among Orientals. We treated a 37-year-old man with severe pulmonary emphysema associated with a low serum concentration of alpha1AT. Mutation analysis of the alpha1AT gene was performed using a reverse transcription-polymerase chain reaction followed by sequencing. The patient proved to be a compound heterozygote carrying a S(iiyama) deficient allele and a QO(clayton) null allele. This is the first Japanese case of alpha1AT deficiency to arise from such compound heterozygosity in a family with no apparent consanguineous marriage, suggesting that the gene frequency for deficient alleles might be somewhat higher than previously estimated.

Adult↗
PubMed2001

[A case of advanced gastric cancer that was resectable after asctic fluid had disappeared following administration of TS-1].

A 60-year-old man who had suffered from epigastic pain and general malaise from November 1999 was admitted to our hospital due to Borrmann type 3 gastric cancer with ascites on December 7, 1999. We considered a radical B operation impossible, and placed the patient on neoadjuvant TS-1 chemotherapy consisting of 1 M tegafur, 0.4 M gimestat, and 1 M otastat potassium. There were no side effects other than Grade 1 nausea and mild loss of appetite throughout the chemotherapy. After 8 weeks of administration, the primary lesion was reduced in size, and ascitic fluid had disappeared on abdominal computed tomography images. Therefore, a total gastrectomy with splenectomy and D2 lymph node dissection was performed on March 31, 2000. This was a radical B operation that was not possible earlier. The pathological diagnosis was tub2, SE, N1, CY0, H0, P0, M0, INF gamma, ly1, v1, PM (-), DM (-) and the antitumor efficacy of TS-1 was Grade 2 histologically. The patient remains alive and in good condition with no relapse of the gastric cancer 8 months after surgery.

Antimetabolites, Antineoplastic↗
PubMed2001

[Efficacy of intraperitoneal chemotherapy for peritoneal recurrence of gastric carcinoma].

We report a patient in whom intraperitoneal chemotherapy was effective against peritoneal recurrence of gastric carcinoma. A 74-year-old woman underwent total gastrectomy with splenectomy and transverse colectomy for Borrmann type IV gastric carcinoma (curability B) in January 2000. The diagnosis was Stage IV gastric carcinoma (T4, N2, P1, H0, M0 and CY0). In July 2000, peritoneal recurrence occurred along with slight elevation of CEA. In September, two ports were inserted into the upper and lower peritoneal cavity for intraperitoneal chemotherapy with low-dose CDDP and 5-FU plus MMC. She was followed-up for four months as an outpatient and received intraperitoneal chemotherapy biweekly with good control of peritoneal metastasis. However, she died of bone and lung metastases in January 2001. Intraperitoneal chemotherapy was effective in this patient for peritoneal recurrence of gastric carcinoma and could be delivered on an outpatient basis while maintaining the patient's quality of life.

Administration, Oral↗
PubMed2001

[Orchiectomy for tuberculous epididymitis: a report of two cases with intractable to antituberculosis treatment].

This paper describes two cases with tuberculous epididymitis. The first case was a 69-year-old man who was admitted to our hospital because of ulceration or right scrotum. Physical examination revealed a hard, rounded, a little bigger than egg-sized mass in the right scrotum. The second case was a 40-year-old man who was admitted to our hospital because of cough, fever and body weight loss. He was treated for pulmonary tuberculosis with isoniazid, rifampicin, streptomycin and pyrazinamide. Six months after admission, he complained of a painless swelling of the right scrotum. Physical examination revealed a hard, rounded, more than egg-sized mass in the right scrotum. Right orchiectomy was performed in these two cases, and they were cured.

Adult↗
PubMed2001

[Bacteria isolated from surgical infections and their susceptibilities to antimicrobial agents. Special references to bacteria isolated between April 1998 and March 1999].

The annual multicenter studies on isolated bacteria from infections in general surgery and their antimicrobial susceptibility have been conducted in Japan since July 1982. This paper describes the results obtained in fiscal 1998 (from April 1998 to March 1999). The number of cases investigated as objectives was 225 for one year. A total of 429 strains (121 strains from primary infections and 308 strains from postoperative infections) were isolated from 183 cases (81.3% of total cases). In primary infections, the isolation rates of anaerobes and Escherichia coli were higher than in postoperative infections, while in postoperative infections, those of Gram-positive aerobes and Pseudomonas aeruginosa were higher than in primary infections. On the whole, among Gram-positive aerobes, the isolation rate of Enterococcus faecalis was the highest, followed by Staphylococcus aureus with high frequency in isolation from postoperative infections. Among Gram-positive anaerobes, Peptostreptococcus spp. and Streptococcus spp. were predominantly isolated. Among Gram-negative aerobes, E. coli, P. aeruginosa, Klebsiella pneumoniae and Enterobacter cloacae were frequently isolated. Among Gram-negative anaerobes, Bacteroides fragilis group was the majority of isolates. In primary infections, the percentage of Gram-negative aerobes has gradually increased since fiscal 1995 or 1996 with these years as the turning point, while those of Gram-positive and Gram-negative anaerobes have gradually declined. In postoperative infections, the percentage of Gram-negative anaerobes has increased continuously since the mid-1980s. The percentage of MRSA among S. aureus rose to 89.7%, which was the highest level since the beginning of this study. The susceptibilities of B. fragilis, which did not show apparent changes, were recognized to have decreased against cephems in fiscal 1998. Among other bacteria in B. fragilis group, development of resistance to cephems has continued on a long-term basis since the mid-1980s. E. coli and K. pneuminiae have obviously not changed in susceptibilities, however, the susceptibilities of isolated strains in fiscal 1998 against high-generation cephems, oxacephems and monobactams have declined. We found neither vancomycin-resistant nor teicoplanin-resistant strains of S. aureus and Enterococcus spp.

Anti-Bacterial Agents↗
PubMed2000

Cloning and characterization of a gene, mpsA, encoding a protein associated with intracellular magnetic particles from Magnetospirillum sp. strain AMB-1.

Proteins located within the lipid bilayer, surrounding the intracellular bacterial magnetic particles (BMP) from Magnetospirillum sp. AMB-1, were separated using SDS-PAGE. Several major proteins of approximate molecular weight 66.2, 35.6, and 24.8 kDa were identified. The N-terminal amino acid sequence of one of these proteins, designated MpsA, was determined and used to design a pair of PCR primers which amplified a 105 bp DNA fragment from AMB-1 genomic DNA. Gene-walking, using anchored PCR, was used to determine the complete nucleotide sequence (954 bp) of the mpsA gene. The mpsA encodes a 317 amino acid protein which does not have an N-terminal cytoplasmic transport signal sequence. Intracellular localization studies were carried out using an mpsA-luc gene fusion expressed in AMB-1 following gene transfer by conjugation. The gene fusion was constructed by cloning a 1.6 kb mpsA fragment upstream of luc in the conjugal plasmid pKLC. The MpsA-Luc fusion protein was preferentially located on the magnetic particle membrane. Although the function of MpsA remains unknown, homology searches suggest similarity with the alpha subunit of acetyl-CoA carboxylase and the CoA-binding motif.

Amino Acid Sequence↗
PubMed2000

Two Tandemly Arrayed Transfer-RNA-Derived SINEs of the Medaka (Oryzias latipes).

Two tandemly arrayed short interspersed repetitive element (SINE) sequences were found in medaka (Oryzias latipes). These two SINE sequences, designated SINE1 and SINE2, were flanked by a 180-bp AT-rich region. Both appeared to be derived from transfer RNA. The former exhibited 80% sequence homology to human tRNA(Ala) and the latter exhibited 94% sequence homology to rat tRNA(Ser). SINE1 contained the retroviral U5 region, whereas SINE2 did not. This is the first sequence-level demonstration of the existence of neighboring SINEs in medaka.

Journal Article↗
PubMed2000

Discrimination between Atlantic and Pacific Subspecies of Northern Bluefin Tuna (Thunnus thynnus) by Magnetic-Capture Hybridization Using Bacterial Magnetic Particles.

The previously developed magnetic-capture hybridization technique employing bacterial magnetic particles was applied to discriminate between Atlantic and Pacific subspecies of the northern bluefin tuna (Thunnus thynnus) using specific DNA sequences. Nucleotide sequences of a 925-bp fragment (ATCO) flanking the mitochondrial ATPase and cytochrome oxidase subunit III genes in these two subspecies were compared. Two regions having single-nucleotide and three-nucleotide differences between the subspecies were adopted to design DNA probes (NR1, 21-mer; NR2, 29-mer), and two internal primer sets were designed to amplify DNA fragments containing these regions. The DNA probes were immobilized on bacterial magnetic particles via streptavidin-biotin conjugation and subjected to magnetic-capture hybridization with the digoxigenin-labeled fragments amplified using the internal primers. The luminescence intensities of DNA on bacterial magnetic particles obtained by hybridization between the probes and the complementary fragments were higher than those obtained by hybridization with noncomplementary fragments. These data suggest that this system employing DNA on bacterial magnetic particles may be useful for discrimination of these two subspecies by recognizing a single-nucleotide difference.

Journal Article↗
PubMed2000

Production of eicosapentaenoic acid by a recombinant marine cyanobacterium, Synechococcus sp.

The eicosapentaenoic acid (EPA) synthesis gene cluster from an EPA-producing bacterium, Shewanella sp. SCRC-2738, was cloned into a broad-host range vector, pJRD215, and then introduced into a marine cyanobacterium, Synechococcus sp. NKBG15041c, by conjugation. The transconjugant cyanobacteria produced 3.7 +/- 0.2% (2.24 +/- 0.13 mg/L) EPA (n-3) and 2.5 +/- 0.2% (1.49 +/- 0.06 mg/L) eicosatetraenoic acid (n-3) of the total fatty acids when the cells were cultured at 23 degrees C at a light intensity of 1,000-1,500 Lux. The EPA and eico-satetraenoic acid contents of the cells were increased to 4.6 +/- 0.6% (3.86 +/- 1.11 mg/L) and 4.7 +/- 0.3% (3.86 +/- 0.82 mg/L), and 7.5 +/- 0.3% (1.76 +/- 0.10 mg/L) and 5.1 +/- 0.2% (1.19 +/- 0.06 mg/L) when they were cultured at low temperature (18 degrees C) and at lower light intensity (40 Lux), respectively.

Alteromonas↗
PubMed2000

PCDDs/DFs emissions from crematories in Japan.

Concentrations of PCDDs and PCDFs in emission gases from 10 crematories were measured. The relationship between PCDDs/DFs and several factors such as structure, equipment and operational state of the crematory is discussed. Furthermore, emission of PCDDs/DFs from all crematories in Japan is estimated. The following results are obtained: (1) total concentration of PCDDs/DFs was 2.2-290 ng/N m3, whose TEQ concentration was 0.0099-6.5 ng TEQ/N m3; (2) total concentration of PCDFs was higher than that of PCDDs; (3) T4CDFs was the highest in the homologue pattern and 2,3,7,8-T4CDF was the highest in the isomer pattern; (4) emission of PCDDs/DFs was the largest in the first 20 min of cremation; (5) concentration of PCDDs/DFs was related to the existence of a secondary combustion chamber and a dust collector, and the ratio of the numbers of main and secondary combustion chambers; (6) total emission of PCDDs/DFs from crematories in Japan was estimated to be 8.9 g TEQ/yr.

Age Factors↗
PubMed2000

Acetylcholine-induced smooth muscle contraction of intrapulmonary small bronchi is augmented in antigen-induced airway hyperresponsive rats.

Smooth muscle responsiveness of intrapulmonary small bronchi obtained from repeatedly antigen-challenged rats was compared with that from control animals to determine whether smooth muscle contractility of peripheral airways is augmented by such repeated challenge. In intact (non-permeabilized) smooth muscles of intrapulmonary bronchi, the acetylcholine (ACh)-induced contractile response was significantly augmented in the repeated challenge group, although 60-mM K+-induced contraction was within the normal level. In beta-escin-permeabilized muscles, no significant difference between groups was observed in the Ca2+-induced contractile responses. Thus, augmented ACh-induced contraction of intact intrapulmonary small bronchial smooth muscle might be, at least in part, due to an enhanced ACh-mediated Ca2+-sensitizing signal.

Acetylcholine↗
PubMed2000

Two-dimensional analysis of proteins specific to the bacterial magnetic particle membrane from Magnetospirillum sp. AMB-1.

We report the identification of five proteins expressed specifically on the bacterial magnetic particle (BMP) membrane of Magnetospirillum sp. AMB-1. These proteins are major components of the BMP membrane. The molecular weights were determined to be 12.0, 16.0, 24.8, 35.6, and 66.2 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Of these five, the 16.0-kDa protein was the most abundant in the BMP membrane. Furthermore, the 16.0-kDa protein consisted of two components each of differing pI. The 35.6-kDa protein was the second most abundant protein of the five detected.

Bacterial Proteins↗