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Biomedical subjects

M Hiyoshi

Publications and source records attributed to M Hiyoshi.

At least 19 recordsLinked to original sources
PubMed2001

Enhancement of oxidative damage to cultured cells and Caenorhabditis elegans by mitochondrial electron transport inhibitors.

The mechanisms that lead to mitochondrial damage under oxidative stress conditions were examined in primary and cultured cells as well as in the nematode Caenorhabditis elegans (C. elegans) treated simultaneously with electron transport inhibitors and oxygen gas. Oxygen loading enhanced the damage of PC 12 cells by thenoyltrifluoroacetone (TTFA, a complex II inhibitor), but did not by rotenone (a complex I inhibitor), antimycin (a complex III inhibitor), and sodium azide (a complex IV inhibitor). In primary hepatocytes, the enhancement was observed with the addition of sodium azide and rotenone, but not by TTFA or antimycin. In the nematode, only rotenone and TTFA enhanced the sensitivity under hyperoxia. These results demonstrate that highly specific inhibitors of electron transport can induce oxygen hypersensitivity in cell levels such as PC 12 cells and primary hepatocytes, and animal level of C. elegans. In addition the cell damage is different dependent on cell type and organism.

Animals↗
PubMed2000

Detection of factor V Leiden in Thai patients with venous thrombosis.

The molecular defect underlying activated protein C resistance (APC-R) is caused by a G to A point mutation in the codon for arginine 506 in the factor V gene (factor V Leiden) which is a major risk factor for venous thrombosis, especially in Caucasian populations. This study is an analysis of the Thai population to determine the prevalence of the factor V Leiden mutation. Twenty-seven patients with apparent venous thrombosis were divided into two groups according to APC-R test. Thirteen patients were diagnosed as positive for n-APC-SR, ratio < 0.8 and fourteen patients were diagnosed as negative for n-APC-SR, ratio > 0.8. Two of thirteen APC-R positive patients and one of fourteen APC-R negative patients were found to have the heterozygous allele for the factor V Leiden mutation but the homozygous allele was not detected in these groups of patients. Neither the heterozygous nor homozygous Leiden mutation was detected in 200 healthy volunteer blood donors. In conclusion, our findings indicate that factor V Leiden mutation is related to venous thrombosis in Thai people. Moreover, a further study of other mutations at the activated protein C cleavage sites of factor V and factor VIII is recommended.

Activated Protein C Resistance↗
PubMed1999

Effects of glucocorticoids on bone mineral density in rheumatoid arthritis patients. A longitudinal study.

We carried out a comparative study in 78 post-menopausal women with rheumatoid arthritis (RA). Forty-four women with a mean disease duration of 17.5 years had been treated with low-dose glucocorticoid (prednisone at < 5 mg/day) for at least 12 months. They were studied for an average period of 3 years and 8 months. The remaining 34 women had been treated only with nonsteroidal anti-rheumatic drugs (NSAIDs) and served as the control group. Bone mineral density (BMD) in the lumbar spine (L2-4) and femoral neck was measured by dual-energy X-ray absorptiometry (DXA). Reduction of BMD in the lumbar spine was significant in both groups (P < 0.05 to approximately 0.01), but there was no statistically significant difference between the two groups. BMD of the femoral neck decreased significantly (P < 0.05) in the prednisone group, but again the difference was not significant between the two groups. Our data suggest that low-dose prednisone administration probably does not induce significant axial bone loss in female RA patients.

Absorptiometry, Photon↗
PubMed1999

Evaluation of a new laboratory test measuring plasma (1-->3)-beta-D-glucan in the diagnosis of Candida deep mycosis: comparison with a serologic test.

We evaluated the effectiveness of the newly developed WAKO beta-glucan test which measures plasma (1-->3)-beta-D-glucan concentrations in the diagnosis of Candida deep mycosis. This test was compared to the Cand-Tec test. The WAKO beta-glucan test and Cand-Tec test were performed on 212 plasma specimens which were taken at 212 instances from 62 immunocompromised patients with serious diseases; i.e. hematopoietic malignancy, solid malignant tumor, etc. The sensitivities and specificities for the WAKO beta-glucan test were 84.8 and 85.9%, respectively, and 60.9 and 80.0% for the Cand-Tec test.

Candidiasis↗
PubMed1999

[A clinical evaluation of the new laboratory method that diagnoses bacterial infection, using silkworm larvae plasma].

Based upon the phenomenon that the peptidoglycan, a common component of Gram positive and negative bacteria, reacts specifically with silkworm larvae plasma (SLP), a new laboratory method named "SLP test" was developed to measure the reaction products in plasma quantitatively as SLP. This SLP test seems to be able to diagnose both Gram positive and negative bacterial infection. So we evaluated its usefulness in diagnosing clinical infectious diseases. This study included 14 patients with result to positive bacterial blood culture, 22 patients with bacterial local infection, 7 patients without any evidence of bacterial infection, and 19 healthy volunteers. It seemed that the cut-off value of this SLP test should be set at 0.6 ng/ml. The sensitivity and specificity of this SLP test were 57.1%, 100%, respectively. A significant difference was not detected statistically between SLP values of patients with Gram positive and Gram negative bacterial infectious diseases. So the SLP test did not appeared specific to either Gram positive or Gram negative bacteria. This test may become a new method diagnosing bacterial infectious disease.

Adult↗
PubMed1999

Which type of underlying disease facilitates cytomegalovirus infection? Comparison of benign disease, hematopoietic malignancy, and post-bone-marrow or renal transplantation status by using the first standardized objective PCR test for cytomegalovirus detection.

All immunocompromised hosts, such as infants, the elderly, patients with advanced cancer, and patients being treated with immunosuppressants, etc., are said to be more susceptible to cytomegalovirus (CMV) infection or CMV disease. However, we questioned the validity of this conclusion and attempted to detect CMV viremia in the plasma of subjects by using the AMPLICOR CMV test (Roche Diagnostics Systems, Branchburg, NJ), the first standardized PCR kit for CMV infection. One hundred healthy volunteers whose CMV IgG titer was < 4 and 100 healthy volunteers whose IgG titer for CMV was > or = 4 were studied. None of the subjects in either healthy group was positive for CMV viremia. Patients who were suspected of CMV infection were divided into four groups and tested: [1] 104 patients with benign disease, only one of whom was positive for CMV [2] 99 patients with hematopoietic malignancy who had not undergone bone marrow transplantation and all of whom were negative for CMV infection [3] 120 post-bone-marrow transplantation, 28 of whom were CMV positive, [4] 37 post-renal transplantation patients, 19 of whom were CMV positive. A statistically significant difference in CMV positivity was found by the non-parametric Kruskal-Wallis test (p < 0.0001) among the four disease group. CMV infection has been said to occur in all types of immunocompromised patients, however, based on our findings, we conclude that CMV infection tends to occur in post-transplantation status and does not tend to occur in patients with hematopoietic malignancy if they have not undergone transplantation.

Adult↗
PubMed1998

Reduced susceptibility to collagen-induced arthritis in mice deficient in IFN-gamma receptor.

Collagen-induced arthritis (CIA) is an arthritic model that was developed after immunization with type II collagen (CII). Apparently, contradictory results have been reported regarding the role of IFN-gamma in the development of CIA. Therefore, we employed IFN-gamma R-deficient mice to study the role of IFN-gamma. To introduce the CIA susceptibility gene (H-2q), IFN-gamma R-deficient (H-2b/b/IFN-gamma R-/-) mice were mated with DBA/1 (H-2q/q/IFN-gamma R+/+) mice; next, the F1 mice were interbred to yield F2 offspring bearing different combinations of H-2 (H-2q/q, H-2q/b, and H-2b/b) and IFN-gamma R (IFN-gamma R+/+, IFN-gamma R+/-, and IFN-gamma R-/-) genes. Although the H-2q allele appeared to confer susceptibility to CIA, mice that were homozygous for the IFN-gamma R mutation showed a substantially decreased incidence and severity of CIA. The CII-specific IgG levels of serum samples, which are known to be involved in the development of CIA, were remarkably reduced in IFN-gamma R-/- mice. Furthermore, the anti-CII IgG2a levels controlled by IFN-gamma R were significantly reduced in IFN-gamma R-/- F2 mice compared with those seen in IFN-gamma R+/+ and IFN-gamma R+/- mice, although the levels of all IgG subclass Abs examined were lower in IFN-gamma R-/- mice than in IFN-gamma R+/+ mice. No clear evidence of the imbalance of Th1/Th2 cytokines was observed in CII-immunized, IFN-gamma R-deficient mice. Taken together, these results suggest that IFN-gamma exacerbates CIA by affecting, at least, levels of CII-specific IgG Ab rather than the imbalance of Th1/Th2 cells.

Animals↗
PubMed1998

Outcomes for patients undergoing one or more total hip and knee arthroplasties.

Either total hip arthroplasty (THA), total knee arthroplasty (TKA) or both were performed in 105 patients from 1981 to 1994. These patients were experiencing severe joint destruction in the lower extremities due to rheumatoid arthritis (RA). These patients were followed for more than 2 years after their last operation. Eighty-six patients were alive and 19 patients had died at the time of follow-up. The 86 living patients were divided into four groups based on the number of replaced joints. Their pre- and postoperative conditions, including such factors as pain, mobility and disability for the quality of life (QOL), were compared. All of the four groups showed some reduction in pain and disability, and an improvement in ambulation after the operations. The 19 deceased patients were classified into two groups, one including those with multiple (three or four) arthroplasties and the other, those with only a small number (one or two). The mean age at death was lower (55.7+/-6.2 years) in patients with multiple arthroplasties than that (69.1+/-7.5 years) in patients with only a small number of arthroplasties. Secondary diseases from RA, such as amyloidosis, spinal injury and pulmonary fibrosis, were found to be the primary cause of death in patients with multiple arthroplasties. The most important finding in this study is that although RA patients with multiple arthroplasties in the lower extremities improved their QOL, they were still afflicted with secondary diseases derived from RA and experienced complications that could shorten their lifespan.

Adult↗
PubMed1998

A convenient method of DNA extraction from blood anticoagulated with EDTA.

Surplus blood often remains after routine clinical tests using EDTA-anticoagulated samples. To use this blood for DNA analysis, we isolated white cells by adherence to polyethylene terephthalate fibers, which could be stored for several weeks transported by mail after methanol fixation. DNA yield was sufficient and correlated with white cell count. Extracted DNA was free of hemoglobin contamination and durable to polymerase chain reaction and enzyme digestion, which yielded products visualized as well-separated bands on electrophoresis. We found our method to be practical for the routine clinical laboratory.

Adult↗
PubMed1998

[Treatment of hepatosplenic candidiasis with liposomal amphotericin B in a patient with acute leukemia; a case report of the experience of use of liposomal amphotericin B].

We report a 26-year-old male patient with acute myelocytic leukemia and hepatosplenic candidiasis during his clinical course. His hepatosplenic candidiasis was refractoty to itraconazole and fluconazol. He developed serious side-effect such as renal dysfunction, when conventional amphotericin B was given. Then he was treated with liposomal amphotericin B (Abelcet). This therapy was safe and effective for him. He was able to be treated with 3075 mg of a liposomal amphotericin B. This was ten times as much as the dose of conventional amphotericin B which was given earlier until amphotericin B was stopped because of renal dysfunction. Liposomal amphotericin B seems to be a safe and effective therapy for systemic fungal infectin and should be considered more in Japan.

Adult↗
PubMed1998

DNA extraction from human urinary sediment.

DNA was extracted from urinary sediments and was sufficient for polymerase chain reaction (PCR) and enzymatic analysis, even if DNA from microorganisms coexisted. From urine samples, the yield of DNA ranged from trace levels to 20 micrograms per 10 mL urine. When urinary sediment was stored in ethanol, DNA remained stable for 2 weeks or more. Individual identification and sex determination could easily be performed using either fresh or ethanol-fixed urine. In conclusion, urine can be used as a source for PCR-based investigations and genetic studies.

Adolescent↗
PubMed1997

Successful treatment for active cytomegalovirus infection by cytomegalovirus antibody-enriched immunoglobulin in a renal transplant recipient.

Active cytomegalovirus (CMV) infection was treated successfully by only CMV antibody-enriched immunoglobulin (CMV-IG) in a renal transplant recipient. CMV-IG was injected at 86 mg/kg i.v. twice a day for a total of 16 days (4 plus 12 days, interrupted by a pause of 4 days), followed by weekly i.v. injection of 86 mg/kg (7 weeks). Active CMV infection was diagnosed on the basis of DNAemia in plasma, by a newly developed CMV polymerase chain reaction (PCR) test (AMPLICOR CMV). The disappearance of CMV from plasma was confirmed by this PCR test. It seems that single CMV-IG therapy is worth consideration for the treatment of CMV infection.

Antibodies, Viral↗
PubMed1997

Evaluation of the AMPLICOR CMV test for direct detection of cytomegalovirus in plasma specimens.

We evaluated the AMPLICOR CMV test (PCR) for the direct detection of cytomegalovirus in plasma. Sixty-eight specimens were involved for the comparison between the AMPLICOR test and the antigenemia assay. The sensitivities, specificities, and positive and negative predictive values were 97.1, 100, 100, and 97.1%, respectively, for the AMPLICOR test and 79.4, 100, 100, and 82.9%, respectively, for the antigenemia assay.

Antigens, Viral↗
PubMed1997

[Chronic myelogenous leukemia expressing two bcr-abl chimeric mRNA; a case report].

Chronic myelogenous leukemia (CML) expresses two types of bcr-abl chimeric mRNA. One is b3a2 type in which bcr exon 3 binds to abl exon 2, the other is b2a2 type that bcr exon 2 binds to abl exon 2. Either bcr-abl is normally expressed, but both types of bcr-abl mRNA can be expressed at the same time in a patient. We report here a rare case of CML expressing two types of bcr-abl mRNA and discuss the possibility that this double expression would help to monitor the clinical course of CML.

Adult↗