Search PubMed⌕ Search

Biomedical subjects

Y Mikami

Publications and source records attributed to Y Mikami.

At least 109 records · Page 6Linked to original sources
PubMed2000

New PCR primer pairs specific for Candida dubliniensis and detection of the fungi from the Candida albicans clinical isolates in Japan.

The genetic patterns of Candida dubliniensis, including type strain, were analyzed by random amplified polymorphic DNA (RAPD) method in comparison with those of reference Candida albicans genotypes A, B and C strains. This RAPD pattern analysis showed that the patterns of two strains of C. dubliniensis including the type strain are very similar to the three oligo PCR primers used, but different from other C. albicans genotypes A, B and C strains with most of the PCR primers tested. The RAPD band considered to be specific for C. dubliniensis in one oligo primer was extracted and sequenced. Based on the sequence information (417-bp), two new PCR primer pairs specific for C. dubliniensis were prepared. The survey of 58 strains of Candida clinical isolates using these newly prepared PCR primer pairs identified as C. albicans in Japan suggested the presence of one strain of C. dubliniensis. The phenotypic characteristics and the sequence analysis of the variable D1/D2 domain of the large subunit (26S) ribosomal DNA of the strain confirmed that it belongs to C. dubliniensis. The usefulness and specificity of these PCR primer pairs for the identification of C. dubliniensis are discussed.

Base Sequence↗
PubMed2000

Geographic grouping of Cryptococcus neoformans var. gattii by random amplified polymorphic DNA fingerprint patterns and ITS sequence divergence.

Eleven reference strains of Cryptococcus neoformans var. gattii were analyzed by random amplified polymorphic DNA (RAPD) patterns using three oligo primers. Three major RAPD pattern profiles (profiles I, II and III) were identified with A-1 oligo primer. Each profile was found to relate to a geographic region. Since the strains which belong to profiles I and II were mainly the isolates from America, and profile III from Asia with A-1 primer, these three profiles were assigned to the geographic grouping of America-1, America-2 and Asia, respectively. Analysis of rDNA sequences coding an internal transcribed spacer (ITS) region of C. neformans var. gattii revealed that the fungus with each RAPD profile has characteristic base sequences at the four positions (10 and 15 positions in ITS1 and 8 and 56 positions at ITS2) of the ITS regions. On the basis of the combinations of the four bases specific for the ITS regions, four ITS types, AAGG (America-1), AAAC (America-2), GGGC (Asia-1) and AGGC (Asia-2) were identified: the geographic group of Asia was further classified into two subgroups of Asia-1 and Asia-2 based on the ITS typing. Clinical isolates from Thailand (6 strains) and Brazil (7 strains) were found to belong to the geographic group of America-1 nd America-2, respectively. Five reference strains of C. neoformans var. gattii from the CBS culture collection were classified into two America-2, one Asia-1 and two Asia-2 groups. This ITS region analysis allowed us to distinguish all isolates of C. neoformans var. gattii into four geographic groups based on the ITS base sequence, and further molecular epidemiological and ecological research on this fungus is recommended.

Base Sequence↗
PubMed2000

[A case of clear cell carcinoma of the ovary responding to a paclitaxel-carboplatin combination chemotherapy].

Clear cell carcinoma of the ovary is believed to be chemoresistant; therefore, choosing anticancer agents is often difficult. In this report we present a case of ovarian clear cell carcinoma that showed a significant response to a combination chemotherapy with paclitaxel and carboplatin. The patient is a 51-year-old Japanese female with a history of Gn-RH treatment for endometriosis that was terminated three years before the presentation of this disease. She was referred to our hospital because of a huge abdominal mass. The initial surgery revealed the tumor was a clear cell carcinoma of the left ovary, showing a predominantly solid growth pattern as well as papillary and tubular patterns. Both architectural and nuclear grades were interpreted as 3, and mitotic count was up to 5/10 high-power fields. Therefore, the tumor was considered to be grade 2. A huge para-aortic lymph node metastasis was not resectable. Combination chemotherapy using paclitaxel at 175 mg/m2 in 3 hr intravenous infusion followed by intraperitoneal infusion of carboplatin at AUC of 7.5 as a bolus was administered. The regression rate of the para-aortic lymph node metastasis was 85%, lasting more than 5 months. We believe that the combination of paclitaxel and carboplatin is one treatment choice for clear cell carcinoma of the ovary.

Adenocarcinoma, Clear Cell↗
PubMed1999

Gene for a protein capable of enhancing lateral root formation.

Analysis of genes preferentially expressed in hairy roots caused by infection with Agrobacterium rhizogenes has provided insights into the regulation of lateral root formation. A hairy root preferential cDNA, HR7, has been cloned from hairy roots of Hyoscyamus niger. HR7 encodes a novel protein partially homologous to a metallocarboxypeptidase inhibitor and is expressed exclusively in the primordium and base of lateral roots in hairy roots. Overexpression of HR7 in transgenic roots of H. niger dramatically enhances the frequency of lateral root formation. The results of this study indicate that expression of HR7 plays a critical role in initiating lateral root formation.

Amino Acid Sequence↗
PubMed1999

Florid endocervical glandular hyperplasia with intestinal and pyloric gland metaplasia: worrisome benign mimic of "adenoma malignum".

We describe three cases of florid endocervical glandular hyperplasia with intestinal and pyloric gland metaplasia, which can be a benign mimic of adenoma malignum. In two cases, adenoma malignum was seriously considered preoperatively because of watery vaginal discharge and the results of imaging studies. The three cases shared common histopathological features, i.e., (i) proliferating endocervical glands surrounded by clusters of smaller glands, resembling the pyloric glands of the stomach; (ii) occasional intestinal metaplasia; (iii) bland nuclear features; and (iv) predominantly PAS-positive neutral mucin in the glandular epithelium. In two cases, glands were densely and irregularly arranged in some areas. Immunohistochemistry disclosed that the intracytoplasmic mucin of the metaplastic epithelium was positive for M-GGMC-1 (HIK1083), which reacts with mucin of pyloric glands. Monoclonal CEA was negative in all cases. This pseudoneoplastic benign condition should be recognized by both gynecologists and pathologists, although it might be difficult to establish a definite diagnosis preoperatively even with deep cone biopsy.

Adenoma↗
PubMed1999

Ratio of primary and secondary bile acids in feces: possible marker for colorectal cancer?

PURPOSE: Increases in fecal bile acids may play a role in colorectal carcinogenesis. The authors tested the hypothesis that high concentrations of primary and secondary bile acids are more common in patients with colon cancer than in patients with other gastrointestinal diseases. METHODS: In this retrospective study the secondary bile acid deoxycholic acid and the primary bile acid cholic acid were measured in the feces by enzyme-linked immunoabsorbent assay in 63 patients with colorectal cancer, 24 patients with gastric cancer, 11 patients with biliary disorders, and 47 healthy volunteers. RESULTS: Preoperatively, the mean deoxycholic acid values tended to be higher and the cholic acid values were significantly lower in patients with colorectal cancer than in healthy subjects. Patients with other gastrointestinal diseases had lower deoxycholic acid and cholic acid values than healthy subjects. In healthy subjects the deoxycholic acid to cholic acid ratio ranged from 0.10 to 2.86 (mean, 0.88), but in almost two-thirds, the ratio did not exceed 1. In contrast, the mean preoperative ratio in patients with colorectal cancer was 2.26 (range, 0.06-7.17; P < 0.0001) and tended to be higher in patients with advanced cancer and in those with sigmoid and rectal tumors. If 1.1 is taken as the upper limit of normal for deoxycholic acid to cholic acid ratio, 67 percent of patients with colorectal cancer had an abnormal value preoperatively. CONCLUSION: A high deoxycholic acid concentration and deoxycholic acid to cholic acid ratio may be indicators of colorectal cancer. Further study is needed to improve sensitivity and specificity, perhaps by combining fecal bile acid measurements with other tests, and a large prospective trial may be warranted to determine whether these measurements have value in screening for this common cancer.

Adult↗
PubMed1999

Functional evaluation of myocardial viability by 99mTc tetrofosmin gated SPECT--a quantitative comparison with 18F fluorodeoxyglucose positron emission CT (18F FDG PET).

UNLABELLED: To validate functional analysis of gated SPECT in detecting myocardial viability, seventeen patients (male 15, female 2, mean age 58) with angiographically proven chronic ischemic heart disease (RCA 6, LAD 10, LCX 1) and eight normal volunteers (all male) were studied. All patients underwent 18F FDG PET and 99mTc tetrofosmin (TF) gated SPECT within a week. After being displayed in a polar map, myocardial perfusion was regionally determined by the mean count in 9 segments at end diastole (ED) and end systole (ES) in gated SPECT. Systolic function was determined by the count increase ratio from ED to ES (WTI: ES - ED/ED). Glucose metabolism was assessed by 18F FDG PET in the segments correspondent to those defined for SPECT. TF %uptake of < 60% was defined as hypoperfusion, and FDG %uptake of < 50% was defined as reduced glucose metabolism. RESULTS: The myocardial segments were classified into 3 categories: "normal" perfusion (n = 85), "mismatch" (reduced perfusion with reserved FDG uptake, n = 25) and "matched" reduced perfusion and metabolic reduction (n = 26). Mean WTI in "mismatch" segment was 0.38 +/- 0.21, and was significantly greater than that in "matched reduced" segments, 0.15 +/- 0.20 (p < 0.001). It was also greater than that in "normal" segments, 0.27 +/- 0.16. Regression analysis showed that association between WTI and FDG %uptake was significant (r = 0.57, p < 0.0005) for the ischemic segments ("mismatch" + "matched", n = 51), but the association was weak for the entire segments although it was statistically significant (r = 0.26, p = 0.02, n = 136). CONCLUSION: For the segments determined as infarct by perfusion image, systolic functional analysis by gated SPECT is helpful in differentiation of a viable myocardial region or artifact from a scar. Nevertheless, further clinical and technical assessment is required for ECG gating to eliminate overestimation of viability and to warrant clinical use.

Adult↗
PubMed1999

Insufficiency fracture of the femoral neck after intramedullary nailing.

We report a patient with insufficiency fracture that occurred after intramedullary nailing for a subtrochanteric fracture. Intramedullary nailing is speculated to have increased the stress in the already osteoporotic subcapital region. It therefore should be recognized as a causative factor in insufficiency fracture of the femoral neck. Careful follow-up is needed for patients with this condition.

Aged↗
PubMed1999

Low-grade endometrial stromal sarcoma with intracardiac extension. Evolution of extensive smooth muscle differentiation and usefulness of immunohistochemistry for its recognition and distinction from intravenous leiomyomatosis.

This case, a rare example of low-grade endometrial stroma sarcoma with extensive smooth muscle differentiation which extended to the inferior vena cava and cardiac chambers closely resembling intravenous leiomyomatosis grossly and microscopically, illustrates the importance of extensive sectioning and the usefulness of immunohistochemistry. Although spindle cell components arranged in interlacing bundles consistent with smooth muscle differentiation were recognizable in the primary tumor (on retrospective review), extensive smooth muscle differentiation in the recurrent tumors masked prototypical morphologic features of stromal sarcoma and only small neoplastic stromal components were preserved in limited areas, leading to initial failure to distinguish the lesion from intravenous leiomyomatosis. The immunophenotyping disclosed two distinct cell populations in the tumor: i.e. vimentin-positive and smooth muscle marker negative stromal cells, and vimentin-negative spindle-shaped desmin-positive smooth muscle cells. Our observation suggests that the predominance of a smooth muscle component in such a tumor can be misleading and does not always warrant a diagnosis of intravenous leiomyomatosis, nor does it predict a benign clinical course. This case also provides an insight into the relationship of the endometrial stroma and myometrium, and their cell of origin and the histogenesis of endometrial stromal sarcoma.

Actins↗
PubMed1999

Antifungal susceptibility of Aspergillus species isolated from invasive oral infection in neutropenic patients with hematologic malignancies.

OBJECTIVE: The aim of this study was to evaluate the relevance of in vitro antifungal susceptibility to clinical response in neutropenic patients with invasive oral aspergillosis. STUDY DESIGN: Nine isolates of Aspergillus species were obtained from invasive oral infections in 9 patients with hematologic malignancies and tested for their in vitro susceptibility to amphotericin B, fluconazole, miconazole, 5-fluorocytosine, and itraconazole. Minimal inhibitory concentration values of the 5 drugs were obtained for each fungus through use of a microdilution broth method. The patients were treated with intravenous amphotericin B (30-50 mg/day) in combination with oral 5-fluorocytosine (3000-6000 mg/day) and/or oral itraconazole (200 mg/day). RESULTS: Amphotericin B and itraconazole were found to be very active, with minimal inhibitory concentration values of 0.861 and 0.194 microg/mL, respectively. Miconazole and 5-fluorocytosine showed minimal inhibitory concentration values of 1.72 and 3.56 microg/mL, respectively. On the other hand, fluconazole FCZ showed low activity, with a minimal inhibitory concentration value in excess of 64.0 microg/mL. During neutropenia, combined antifungal chemotherapy stabilized oral aspergillosis and prevented the spread of oral lesions in 8 patients in whom neutrophil counts eventually recovered. CONCLUSIONS: The results imply that in vitro susceptibility testing may serve as an informative parameter with respect to the efficacy of these antifungals in the treatment of invasive oral aspergillosis, inducing fungal stasis until the neutrophils recover.

Adult↗
PubMed1999

Morphological and immunohistochemical changes in intestinal mucosa and PYY release following total colectomy with ileal pouch-anal anastomosis in dogs.

Other studies have shown that both morphological and functional adaptation occur in the ileal mucosa after total colectomy and may be mediated by humoral factors. To elucidate the participation of peptide YY (PYY) in intestinal adaptation after total proctocolectomy with ileal pouch-anal anastomosis (IPAA), changes in the number of PYY-containing cells and in histological appearance in the intestinal mucosa, especially in the mucosa of ileal pouch, were investigated in dogs. We further examined changes in postprandial PYY release in relation to those in PYY-containing cells. Ten adult beagle dogs underwent IPAA. Before and 2, 6, and 12 months after surgery, a test meal was given, and blood samples were taken from a foreleg vein at intervals for 3 hr for measurements of plasma PYY concentration by radioimmunoassay. Before and one year after surgery, morphological studies of the intestinal mucosa were performed using parameters such as villous height (VH), mucosal thickness (MT), and villous index (VI). Immunohistochemical studies of PYY were also done in the intestinal mucosa. Both fasting and postprandial plasma PYY levels were reduced to half of the preoperative levels at two months after surgery. Thereafter, postprandial levels approached preoperative concentrations, while fasting levels remained unchanged. VH, MT, and VI were significantly smaller in the ileal pouch than in the ileal end of the controls. The MT of the ileal pouch was similar to that of the colon. PYY-containing cells in the mucosa of the ileal pouch were distributed more densely than those in the ileal end, similar to those in the colon of the controls. It was concluded that after IPAA, the pouch mucosa gradually changed to resemble the colonic mucosa not only in histological appearance but also in the population of PYY-containing cells. It is therefore considered that colonic transformation of the ileal-pouch mucosa is closely related to the increase in the number of PYY-containing cells and the steady recovery of postprandial PYY secretion.

Animals↗
PubMed1999

Identification and characterization of a new intermediate in the ribosylative inactivation pathway of rifampin by Mycobacterium smegmatis.

Mycobacterium smegmatis DSM 43756 inactivates rifampin by ribosylation. To study this process of rifampicin, all possible inactivated forms of the antibiotic were extracted and purified. Structural studies showed the presence of a new inactivation product, designated RIP-TAp(23-phosphoribosyl-rifampin). Formation of 23-(O-ADP-ribosyl)rifampin (RIP-TAs) is the first step, followed by removal of AMP to give rise to the newly identified compound. Lastly, dephosphorylation leads to formation of 23-ribosyl-rifampin (RIP-Mb). Feeding experiments with the ADP-ribosylated antibiotic obtained from the cell homogenates of an Escherichia coli strain carrying the cloned M. smegmatis gene confirmed this rifampin inactivation process.

Antibiotics, Antitubercular↗
PubMed1999

Basement membrane material in ovarian clear cell carcinoma: correlation with growth pattern and nuclear grade.

Stromal hyalinization in ovarian clear cell carcinomas has been suggested to be caused by deposition of basement membrane (BM) material, but the biological and diagnostic significance of this finding remains unknown. The distribution of BM material in 17 primary ovarian clear cell carcinomas was examined semiquantitatively using hematoxylin and eosin-stained sections and immunohistochemistry with antibodies to laminin and type IV collagen. For comparison, other surface epithelial tumors, including 8 serous tumors of low malignant potential, 10 serous adenocarcinomas, 6 mucinous tumors of low malignant potential, 5 mucinous adenocarcinomas, 6 endometrioid carcinomas, 4 Brenner tumors, 1 transitional cell carcinoma, and 3 undifferentiated carcinomas, were examined. Stromal hyalinization was found in all 17 clear cell carcinomas and was immunoreactive for type IV collagen and laminin. Other types of surface epithelial tumor lacked these findings. In clear cell carcinoma, areas showing a papillary pattern tended to show abundant deposition regardless of nuclear grade, whereas in solid, tubular, or cystic areas, the deposition was more prominent in areas showing high-nuclear-grade features (grade 2 and 3) than in areas with low-nuclear-grade features (grade 1). Dense deposition of BM material recognized as stromal hyalinization on hematoxylin and eosin-stained sections in primary ovarian clear cell carcinoma is a characteristic feature that is not seen in other ovarian surface epithelial tumors. This matrix production correlates with high-nuclear-grade features and papillary growth pattern.

Adenocarcinoma, Clear Cell↗
PubMed1999

Expression of vascular endothelial growth factor (VEGF) family members in breast cancer.

Vascular endothelial growth factor (VEGF)-A is known to play an important role in tumor angiogenesis. Three additional members of the VEGF family, VEGF-B, -C and -D, have recently been discovered. VEGF-C and VEGF-D are ligands for VEGF receptor-3, which is expressed in the endothelium of lymphatic vessels. The expression of VEGF-C is known to be associated with the development of lymphatic vessels. Therefore, it is conceivable that VEGF-C and VEGF-D might play a role in the development of lymphatic vessels in solid tumors. To obtain some clue as to this role, we developed a semi-quantitative reverse transcription-polymerase chain reaction method to investigate the mRNA expression levels of each VEGF family member in breast cancer. All the VEGF family members were expressed at different levels in seven human breast cancer cell lines explored. Although VEGF-A and VEGF-B expressions were detected in both node-positive and node-negative breast tumors, VEGF-C expression was detected only in node-positive tumors. VEGF-D expression was detected only in an inflammatory breast cancer and a tumor which developed an inflammatory skin metastasis. These findings suggest a possible relationship between the expression level of VEGF-C and/or VEGF-D and the development of lymphatic tumor spread.

Adult↗
PubMed1999

Knowledge and reported behaviour concerning the prevention of caries in children: a questionnaire survey of Japanese parents resident in London, UK.

The objective of this study was to assess the knowledge and self-reported behaviours of a sample of Japanese parents resident in London, UK with respect to the prevention of caries in their children. Japanese parents were asked to complete a structured questionnaire which was distributed through the school authorities to seventeen primary schools. Data was collected on: socio-demographics, dental service use in their children, knowledge and reported behaviours with respect to the prevention of dental caries in their children. After one reminder the questionnaire response rate was 69 per cent (n = 111). The mean age of the children was 6.75 years (range 3-12 years) and 73 per cent had been born in Japan. Those respondents with children born in the UK were more likely to take their children to the dentist regularly and more likely to correctly identify the cause and prevention of dental caries. Whilst a majority of respondents reported that their children brushed their teeth twice daily, toothpaste was not used by one quarter of the children. Barriers to dental attendance were identified. Whilst there were some similarities in levels of knowledge and reported behaviours, the parents of Japanese born children were disadvantaged with respect to knowledge about the causes and prevention of dental caries and the use of UK primary dental care services. These parents should be offered information about these issues.

Adolescent↗