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Y Mikami

Publications and source records attributed to Y Mikami.

At least 73 records · Page 4Linked to original sources
PubMed2001

Detection of myocardial viability using rest-redistribution thallium-201 imaging in a stress 99Tcm-tetrofosmin/rest thallium-201 dual-isotope protocol.

This study investigated the utility of optional thallium-201 (201Tl) imaging for detecting myocardial viability in the stress 99Tcm-tetrofosmin/rest 201Tl dual-isotope protocol. Seventy-nine patients with old myocardial infarction and 25 patients with acute myocardial infarction underwent acquisition of three consecutive 201Tl images (early, intermediate and delayed) using the dual-isotope protocol. A polar map was created and defect scores (extent and severity) were determined by comparison with normal control data. Fluorodeoxyglucose positron emission tomography was also performed in 16 patients with old myocardial infarction. In patients with old infarction, the severity score decreased significantly from the early to the intermediate images, and decreased further on the delayed images. In patients with acute infarction, the score increased from the early to the intermediate images, but not on the delayed images. Regional uptake on the delayed images showed a better correlation with the fluorodeoxyglucose images than that on the early images. Redistribution on the delayed images was exclusively observed in the myocardial segments with less uptake than that estimated by fluorodeoxyglucose. In conclusion, addition of delayed 201Tl imaging to the dual-isotope protocol could improve the sensitivity for detecting myocardial viability.

Aged↗
PubMed2001

Characterization of In53, a class 1 plasmid- and composite transposon-located integron of Escherichia coli which carries an unusual array of gene cassettes.

Further characterization of the genetic environment of the gene encoding the Escherichia coli extended-spectrum beta-lactamase, bla(VEB-1), revealed the presence of a plasmid-located class 1 integron, In53, which carried eight functional resistance gene cassettes in addition to bla(VEB-1). While the aadB and the arr-2 gene cassettes were identical to those previously described, the remaining cassettes were novel: (i) a novel nonenzymatic chloramphenicol resistance gene of the cmlA family, (ii) a qac allele encoding a member of the small multidrug resistance family of proteins, (iii) a cassette, aacA1b/orfG, which encodes a novel 6'-N-acetyltransferase, and (iv) a fused gene cassette, oxa10/aadA1, which is made of two cassettes previously described as single cassettes. In addition, oxa10 and aadA1 genes were expressed from their own promoter sequence present upstream of the oxa10 cassette. arr-2 coded for a protein that shared 54% amino acid identity with the rifampin ADP-ribosylating transferase encoded by the arr-1 gene from Mycobacterium smegmatis DSM43756. While in M. smegmatis, the main inactivated compound was 23-ribosyl-rifampin, the inactivated antibiotic recovered from E. coli culture was 23-O-ADP-ribosyl-rifampin. The integrase gene of In53 was interrupted by an IS26 insertion sequence, which was also present in the 3' conserved segment. Thus, In53 is a truncated integron located on a composite transposon, named Tn2000, bounded by two IS26 elements in opposite orientations. Target site duplication at both ends of the transposon indicated that the integron likely was inserted into the plasmid through a transpositional process. This is the first description of an integron located on a composite transposon.

Amino Acid Sequence↗
PubMed2001

Molecular characterization of new clinical isolates of Candida albicans and C. dubliniensis in Japan: analysis reveals a new genotype of C. albicans with group I intron.

The genetic diversity of recent clinical isolates of Candida albicans in Japan was studied on the basis of amplified DNA band lengths determined with a specific PCR primer reported to have been designed to span a transposable intron region in the 25S rRNA gene. Our analyses of 301 clinical isolates of C. albicans showed that they could be classified into five genotypes: genotype A (172 isolates), genotype B (66 isolates), genotype C (56 isolates), genotype D (C. dubliniensis; 5 isolates), and a new genotype (designated genotype E; 2 isolates). The new genotype E was characterized to have a group I intron-like sequence, which is longer than hitherto reported ones and which has a nucleotide sequence length of 962 bp. Our analysis of the 962-bp sequence indicated that it is composed of an intron similar to that of C. dubliniensis of 621 bp with a 341-bp insertion. Analysis of the sequence of the internal transcribed spacer (ITS) region of the genotype E strain showed that its sequence is identical to those of strains of other genotypes, with only a few base substitution differences. Throughout the study, the possible horizontal transfer of the group I intron between C. dubliniensis and C. albicans was suggested. A high degree of correlation between the presence of a group I intron in C. albicans genotype E and susceptibility to the antifungal agent flucytosine was observed. The five isolates of C. dubliniensis examined in the present study showed genetic diversity when they were compared by randomly amplified polymorphic DNA fingerprinting pattern analysis, and this diversity was also confirmed by the analysis of ITS region sequences.

Antifungal Agents↗
PubMed2001

Post-transplant malignant lymphoma with monoclonal immunoglobulin gene rearrangement and polyclonal Epstein-Barr virus episomes.

This report describes the case of an 8 year old boy who developed ileocecal B cell lymphoma after liver transplantation. The patient underwent orthotopic liver transplantation for biliary atresia and had been given immunosuppressive drugs--cyclosporin A and tacrolimus hydrate. Six years after the liver transplantation, the patient had a sudden onset of fever and abdominal pain. Necropsy revealed an ileocecal mass that was a B cell lymphoma. Epstein-Barr virus (EBV) encoded RNA 1 was demonstrated in lymphoma cells and hyperplastic follicular germinal centre cells in various tissues. Although monoclonal immunoglobulin gene rearrangement was detected in the liver, EBV episomes were of polyclonal origin and lytic forms of EBV were also demonstrated by Southern blotting. Immunohistochemically, lymphoma cells were positive for p53 but negative for latent membrane protein 1 and EBV nuclear antigen 2. These findings suggested that this B cell lymphoma might have occurred sporadically, regardless of EBV infection.

Biliary Atresia↗
PubMed2001

Benefit of continuous regional arterial infusion of protease inhibitor and antibiotic in the management of acute necrotizing pancreatitis.

Although we have reported the beneficial effect of continuous regional arterial infusion (CRAI) of protease inhibitor and antibiotic on acute necrotizing pancreatitis (ANP), the optimal timing of the initiation of CRAI therapy has not been clarified. The present study was conducted to evaluate whether the difference of the timing of CRAI therapy may affect the clinical course and outcome in ANP. 73 patients with ANP were stratified into three groups according to the interval between the onset and initiation of CRAI therapy as follows: group I (32 patients in whom CRAI therapy was initiated within 48 h after the onset); group II (22 patients in whom CRAI therapy was initiated between 48 and 72 h after the onset), and group III (19 patients in whom CRAI was initiated more than 72 h after the onset). The mortality rate was 3.2% in group I, 9.1% in group II, and 26.3% in group III. The mortality rate was significantly low in group I compared with that in group III. The frequency of respiratory failure in group I was also significantly low compared with that in group III. CRP and APACHE II score were reduced rapidly in both groups I and II after the initiation of CRAI therapy. These results suggested that the optimal timing of CRAI therapy in ANP should be considered to be within 72 h after the onset.

APACHE↗
PubMed2001

Atypical Cryptococcus neoformans isolate from an HIV-infected patient in Brazil.

Cryptococcus neoformans is an important fungal pathogen in immunocompromised hosts. Capsulation, urease and melanin synthesis activity of the fungus are well known virulence factors. Although artificial melanin-deficient mutants of Cr. neoformans have been investigated, the clinical mutant is rare. We found a Cr. neoformans isolate in the cerebrospinal fluid of an AIDS patient which produced a light tan colony on a caffeic acid cornmeal agar (CACA) plate. The mycological feature of the isolate was as follows; normal capsulation, defective inositol assimilation ability, serotype A; urease-positive; mating type alfa; haploid; extremely slow growth in RPMI 1640 medium, Sabouraud dextrose broth, brain heart infusion broth and yeast nitrogen base; lower production of melanin with L-DOPA substrate; and low virulence to ddY mice. We also investigated the partial DNA sequence of CNLAC1 gene between the 3085th to 3623rd base. There were many substitutions, 3 insertions and 3 deletions in the isolate compared with GenBank accession number L22866. The result indicated some functional disorder in the gene. Although the CACA plate is an excellent selective medium for Cr. neoformans, other identification methods should also be used.

Acquired Immunodeficiency Syndrome↗
PubMed2001

Nocardia brasiliensis infection seen on grafted skin of the dorsum of a foot.

For the past 4 years a 23 y-old female has noticed erythema on the dorsum of the right foot, where skin was grafted due to a traffic accident 20 years ago. She visited the Department of Dermatology of Gifu Prefectural Hospital on Oct. 19, 1998; her general health was good. Physical examination disclosed a swelling with erythema, papules and pustules on the dorsum of the right foot. The results of routine laboratory investigations were within normal limits except for the white blood cell count (11,300/mm(3)), blood sediment rate (25 mm/hrs), C reactive protein (1.21) and rheumatoid factor (x 16.6). Several yellowish and verrucous or wrinkled colonies were grown on Sabourauds agar culture from the biopsied specimen of the foot. Histopathological features showed epidermal hyperplasia with elongation of rete ridges and granulomatous changes in the dermis; many mononuclear and giant cells were present, and several positive fine filamentous and irregularly branching structures with PAS and Grocott stains were seen in the granulomatous nests. Both clinical and histopathological features led to speculation of Nocardia infection, and Nocardia brasiliensis was determined. The patient was treated by surgical total resection including the grafted skin. Although a soybean-sized nodule was seen on the border of the skin-graft of the foot three months later, there was no recurrence after the local resection.

Adult↗
PubMed2001

[Two cases of canine histoplasmosis in Japan].

Histoplasmosis is distributed in tropical, subtropical and temperate zones of the world. The disease is one of the imported mycoses in Japan. To date, although more than 30 human and one canine case of histoplasmosis have been reported in Japan, some including that of the canine might have been infected domestically, since the patients have no history of going abroad. The pathogen of histoplasmosis is thus believed to be present in our country. We examined skin biopsies from two dogs in Tokyo and Kumamoto, and found fungal elements 1-2 or 2-4 microEm in diameter in the macrophages. The homology of DNA sequences for the ITS rRNA gene were correspondent to Ajellomyces capsulatus at a rate of more than 97.4%. Therefore, the two dogs were diagnosed as having been infected with Histoplasma capsulatum which is the anamorph of A. capsulatus. Since the dogs had no history of having been outside Japan and had not been brought from an endemic area, they might have been infected domestically. Further epidemiological surveys on canine histoplasmosis may be able to estimate autochthonous human cases in Japan.

Animals↗
PubMed2001

Detection of gp43 and ITS1-5.8S-ITS2 ribosomal RNA genes of Paracoccidioides brasiliensis in paraffin-embedded tissue.

Paracoccidioidomycosis (PCM) is a deep mycosis caused by the thermo-dependent dimorphic fungus Paracoccidioides brasiliensis and is prevalent in Latin American countries. An increase in PCM has been reported in recent years and the disease is now recognized as one of the imported fungal infections in Japan. To date, more than 15 cases of PCM have been reported in our country, and five of them were diagnosed by clinical and histopathological findings without mycological study. We applied 2 nested polymerase chain reaction (PCR) amplification methods for detecting P. brasiliensis genes from paraffin-embedded tissue specimens. Successfully amplified were: a 473 base pairs fragment of gp43 gene of P. brasiliensis (located from 741st to 1,213rd base), and a 418 base pairs fragment of 5.8S ribosomal RNA gene of P. brasilienisis which included internal transcribed spacers (ITS) 1 and 2 (located from 131st at ITS1 to 195th at ITS2) in paraffin-embedded murine tissues infected with P. brasiliensis yeast cells. The authenticity of the PCR products was confirmed by nucleotide sequence analysis. These results indicate that the two nested PCR methods may be useful for diagnosis of PCM.

Animals↗
PubMed2001

Molecular identification of a clinical isolate of non-pigmented and asporogenic Aspergillus fumigatus strain which cannot be identified by traditional morphological methods.

A non-pigmented and asporogenic fungal strain without taxonomically useful characteristics was isolated from sputum of a patient with chronic bronchitis. Although the taxonomic position could not be determined based on traditional morphological criteria, the fungus was identified as an Aspergillus fumigatus mutant strain by molecular techniques including ITS sequence analysis and PCR identification system using a PCR primer pair specific for A. fumigatus. Usefulness of these molecular techniques for the identification of non-classifiable fungal strains in a clinical laboratory is discussed.

Aspergillus fumigatus↗
PubMed2001

Glycosylative inactivation of chalcomycin and tylosin by a clinically isolated Nocardia asteroides strain.

Studies on the susceptibility of pathogenic Nocardia to macrolide antibiotics, chalcomycin and tylosin, showed that most of the Nocardia species examined were highly resistant to both antibiotics, although N. nova was moderately susceptible. N. asteroides IFM 0339 converted these macrolides into inactive metabolites by glycosylation at 2'-OH or glycosylation and reduction of the 20-formyl group. The structures of the metabolites were determined from NMR and MS data to be 2'-[O-(beta-D-glucopyranosyl)]chalcomycin (2), 2'-[O-(beta-D-glucopyranosyl)]tylosin (5) and 20-dihydro-2'-[O-(beta-D-glucopyranosyl)]tylosin (4).

Anti-Bacterial Agents↗
PubMed2001

[Desmoid tumor of the chest wall infiltrating into the brachial plexus: report of a resected case].

We report a case of a desmoid tumor which developed in the apex of the chest wall. A 18-year-old woman was admitted with left shoulder pain. Chest X-ray showed a mass shadow in the left upper lung field. Chest MRI demonstrated the mass infiltrated into the left brachial plexus. A desmoid tumor was suspected on percutaneous needle biopsy. Resection of the tumor was performed. The mass was 13 x 9 x 5 cm in size and diagnosed pathologically as desmoid tumor. Adjunctive postoperative radiation therapy of 60 Gy was done. Postoperative course was uneventful except motor disturbances of the left fingers. At 15 months postoperatively, there was no evidence of recurrence.

Adolescent↗
PubMed2001

[Effect of combination chemotherapy with nedaplatin and 5-FU for head and neck squamous cell carcinoma].

Nedaplatin (254-S), which is a cisplatin (CDDP) analog, is an effective agent for head and neck squamous cell carcinoma (HNSCC). 254-S is expected to play an important role in neo-adjuvant chemotherapy (NAC) for HNSCC in place of CDDP. We have been using combination chemotherapy including CDDP, 5-FU, MTX and LV. The response rate and CR rate of this 4-drug combined chemotherapy are 87% and 33%. Thirty-six patients with HNSCC were treated with 5-FU, 800 mg/m2/day for 5 days and 254-S, 100 mg/m2 on day 4. Chemotherapy was discontinued in one patient because of allergic shock. Three patients showed a CR and 10 patients showed a PR. The response rate and CR rate of 254-S plus 5-FU chemotherapy were 37.1% and 8.6%. These were inferior to those with the 4-drug combined chemotherapy. Fourteen percent of patients showed grade 3 leukocytopenia, and 17% showed more than grade 3 thrombocytopenia. The effect of combination chemotherapy of 254-S and 5-FU was inferior to that of the previous chemotherapy including CDDP, 5-FU, MTX and LV. Further study or another combination therapy including 254-S will be essential for improving efficacy against HNSCC.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

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Journal Article↗
PubMed2000

Negative MRI findings with invasive cervical biopsy may indicate stage IA cervical carcinoma.

OBJECTIVE: We attempted to prospectively determine the role of magnetic resonance imaging (MRI) in very early cervical cancer. STUDY DESIGN: T2-weighted and T1-dynamic enhanced images from patients with invasive or noninvasive lesions of the cervix were reviewed by two radiologists who had no clinical information on these patients. At least 12 longitudinal sections prepared from the surgically removed cervix were reviewed by a pathologist. The correlation between MRI and histological findings was analyzed in terms of depth of invasion. RESULTS: Seventy-nine cases were entered into the study and 75 were evaluable. Accuracy of T2 MR images for invasive and noninvasive disease by Radiologist 1 and Radiologist 2 was 0.8533 and 0.7733, respectively. Accuracy was greater (0.9867 and 0.9467, respectively) for the detection of noninvasive plus microinvasive lesions </=5 mm vs invasive lesions >5 mm. Dynamic technique provided only limited additional value in the detection of microinvasive cervical carcinoma. CONCLUSION: Simple T2 MRI is useful in differentiating noninvasive or microinvasive cervical lesions from invasive cervical carcinoma of the cervix >5 mm.

Adult↗
PubMed2000

Pregnancy in a woman with a Y chromosome after removal of an ovarian dysgerminoma.

BACKGROUND: It appears to be a general belief that pregnancy might be impossible in women with the XY karyotype. Therefore, it is recommended that patients with dysgerminoma of the ovary associated with the XY karyotype should undergo a bilateral salpingo-oophorectomy. CASE: We report an extremely rare case of a true hermaphrodite with a 20% 46,XX/80% 46,XY karyotype who became pregnant after removal of an ovarian dysgerminoma. The patient had a completely normal female phenotype. A dysgerminoma with ovotestis was found in the right ovary. Two courses of chemotherapy following a right salpingo-oophorectomy were carried out. Nine months later she became pregnant and delivered a healthy male infant. CONCLUSION: A unilateral salpingo-oophorectomy followed by combination chemotherapy can be the treatment of choice for any woman who wishes to preserve her capacity for conception at the time of operation for dysgerminoma of the ovary.

Adolescent↗