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Biomedical subjects

S Yoshida

Publications and source records attributed to S Yoshida.

At least 37 records · Page 2Linked to original sources

Living-related small bowel transplantation: two cases experiences.

We have recently performed living-related small bowel transplantation for 2 patients. The first patient was a 14-year-old boy with total parenteral nutrition (TPN)-dependent short-bowel syndrome associated with hypoganglionosis of the entire intestine. He received a bowel graft from his 43-year-old mother. The second patient was a 27-year-old woman, who had massive enterectomy due to volvulus and developed vitamin deficiencies and severe metabolic disorders as a result of long-term TPN. She underwent living-related bowel transplantation from her 57-year-old mother. Blood types were ABO identical, cytotoxic cross matches were negative, and cytomegalovirus statuses were positive-to-positive in both cases. Up to one third of the donor bowel was harvested from the donor distal ileum more than 30 cm away from the ileocecal valve. The graft vessels were connected to infrarenal aorta, and inferior vena cava. The immunosuppressive regimen consisted of daclizumab, tacrolimus, and steroid. The graft surveillance was accomplished using zoom endoscopy and mucosal biopsy. The first patient developed progressive acute cellular rejection (ACR) on the 9th postoperative day (POD)-9 requiring OKT-3 therapy, which was effective. Two months after transplantation, he was weaned from TPN, tolerating oral intake with a fully functioning graft. The second patient experienced no episode of ACR and was weaned off TPN on POD-29 with a functioning graft. Her metabolic disorder dramatically improved after bowel transplantation. Both donors had no complication and were discharged from the hospital on POD-10. Living-related bowel transplantation is an extreme option of treatment for patients with short-bowel syndrome.

Adolescent↗

Novel mutation in ABCC6 gene in a Japanese pedigree with pseudoxanthoma elasticum and retinitis pigmentosa.

PURPOSE: To report a novel mutation of the ABCC6 gene in a Japanese family that had a case of pseudoxanthoma elasticum (PXE) another with PXE and retinitis pigmentosa. METHODS: Ophthalmologic examinations were performed, and the ABCC6 gene was analysed by direct genomic sequencing. RESULTS: Fundus examinations of the 48-year-old proband disclosed angioid streaks and a peud'orange appearance of the retina of the both eyes, whereas both of his 25- and 20-year-old daughters had pigmentary degeneration and angioid streaks. In the sibilings, the mixed cone-rod ERG was almost nondetectable, whereas that of the proband was well-preserved. Molecular genetic analysis revealed that the proband has a homozygous nonsense mutation at the 595 bp in the ABCC6, and the siblings were heterozygous for the same mutation. This mutation was not detected in Japanese subjects in the JSNP database (http://snp.ims.u-tokyo.ac.jp/). CONCLUSIONS: Our results demonstrated an association between a novel mutation in the ABCC6 gene and PXE in a Japanese family.

Adult↗

Allogeneic hematopoietic stem cell transplantation provides sustained long-term survival for patients with adult T-cell leukemia/lymphoma.

Adult T-cell leukemia/lymphoma (ATLL) is a distinct peripheral T-cell neoplasm that is highly resistant to chemotherapy. Several groups, including ours, have reported encouraging results of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with ATLL. To confirm our previous report and to establish the basis for a phase II clinical study, we analyzed 40 allo-HSCT for acute and lymphoma types of ATLL in seven institutions in Japan between 1997 and 2002. All evaluable cases entered complete remission (CR) after allo-HSCT and the median survival time was 9.6 months for all patients. The estimated 3-year overall and relapse-free survival, and disease relapse were 45.3, 33.8 and 39.3%, respectively. Among 10 cases with ATLL relapse, five cases achieved CR again: three by the reduction or cessation of immunosuppressive agents, which suggested a graft-versus-ATLL (GvATLL) effect. However, univariate or multivariate analysis did not show any benefit of graft-versus-host disease (GVHD) on the prevention of relapse. These results suggested that allo-HSCT was effective for some patients with aggressive ATLL, and that the GvATLL effect could be achieved even without GVHD. A new phase II trial to test the efficacy of allo-HSCT for ATLL is warranted.

Adult↗

Prevention of amputation caused by rheumatic diseases following a novel therapy of exposing bone marrow, occlusive dressing and subsequent epidermal grafting.

BACKGROUND: Wounds with exposed bones caused by rheumatic diseases commonly result in amputation despite progress in our understanding of wound-healing mechanisms. OBJECTIVES: To determine whether an experimental therapy of bone marrow exposure, an occlusive dressing and subsequent grafting of epidermal sheets accelerates healing and reduces the need for amputation in patients with rheumatic diseases. METHODS: Fifteen patients, including those with rheumatoid arthritis or systemic sclerosis, who had wounds with exposed bones were treated either with the standard procedure, consisting of local wound care, debridement with a scalpel, bed rest and parenteral antibiotics (n = 8), or with a newly developed experimental procedure (n = 7). In that new procedure, the affected bone was initially exposed by debridement with a scalpel, followed by partial excision with a bone scraper until bleeding was observed from the exposed bone. The lesions were immediately covered with an occlusive dressing, and were eventually treated with epidermal grafts obtained from suction blisters. RESULTS: A comparison with standard therapy demonstrated that the time needed for wound healing was similar, but that the newly developed combination therapy reduced the risk of amputation (P = 0.020). No skin ulcers or erosions were observed for at least 1 year in five of seven patients (72%) due to the adoption of stable palmoplantar-type characteristics in grafts derived from the trunk epidermis. CONCLUSIONS: Our study indicates that exposure of bone marrow cells plus an occlusive dressing accelerates the healing of skin ulcers at least partly through the preparation of a healthy well-granulated wound bed and that subsequent epidermal grafting achieves site-specific differentiation through epithelial-mesenchymal interactions.

Adult↗

Bone marrow cells differentiate into wound myofibroblasts and accelerate the healing of wounds with exposed bones when combined with an occlusive dressing.

BACKGROUND: The usefulness of bone marrow cells in accelerating wound healing has not been evaluated despite increasing evidence that bone marrow contains mesenchymal stem cells that have multipotentiality to differentiate into various types of cells after they enter the microenvironment of a specific tissue (niche). OBJECTIVES: To determine the effects of bone marrow cells and occlusive dressings in promoting wound healing in rats. METHODS: We investigated by grafting, biopsy and immunohistochemistry whether various types of cells derived from green fluorescent protein (GFP)-transgenic rats would differentiate into wound component cells when administered topically on the wounds of rats. We also investigated whether topical application of bone marrow cells with an occlusive dressing would accelerate the healing of wounds with exposed bones, as measured by planimetry. RESULTS: GFP-labelled bone marrow cells contained multipotent stem cells that sufficiently differentiated into wound myofibroblasts presenting with alpha-smooth muscle actin in granulation tissue. Other types of cells, including myocytes, adipocytes, peripheral blood cells from buffy coat and dermal fibroblasts, did not express myofibroblast characteristics morphologically or immunohistochemically. Application of bone marrow cells and an occlusive dressing accelerated the repair of wounds with exposed bones, compared with an occlusive dressing only or with the topical administration of bone marrow cells plus a semidry to dry dressing. CONCLUSIONS: Our study indicates that bone marrow cells accelerate the healing of wounds at least in part through their differentiation into wound myofibroblasts. Thus, treatment of wounds with bone marrow cells and a supportive occlusive dressing is effective in promoting the formation of healthy granulation tissue and also for the preparation of an ideal wound bed.

Animals↗

Effect of tacrolimus in a patient with pure red-cell aplasia.

A 78-year-old woman has suffered from pure red-cell aplasia (PRCA) associated with generalized myasthenia gravis and thymoma. Cyclosporin A (CyA) with corticosteroid increased numbers of erythroid cells in her bone marrow cells but she required monthly blood transfusions. Administration of tacrolimus as a substitution for CyA inhibited progression of anemia without the need for further blood transfusion. No serious side effects were observed. This case demonstrates that tacrolimus is another option of treatment for PRCA in patients who fail to respond to CyA.

Aged↗

Long-term follow-up of chronic hepatitis B after the emergence of mutations in the hepatitis B virus polymerase region.

Treatment of chronic hepatitis B has been greatly improved by the use of lamivudine, but mutations occur in the polymerase region of hepatitis B virus (HBV) and lamivudine-resistant mutants frequently develop. The emergence of lamivudine-resistant strains of HBV is a problem for treating chronic hepatitis B using lamivudine. We observed biochemical and virological changes in 15 patients with chronic hepatitis B for a median period of 29 months (range: 4-42 months) after the emergence of lamivudine-resistant mutants of HBV. Patterns of mutation of the polymerase gene were examined by sequencing the LLAQ motif in domain B and the YMDD motif in domain C. Exacerbation of liver dysfunction occurred in 14 (93.3%) of the 15 patients at a median of 4 months after the emergence of mutations. However, exacerbation of liver dysfunction was observed only in four patients (26.7%) at the time of appearance of the first mutations and in 80.0% of the patients at the time of appearance of the second mutations. Increase in serum alanine aminotransferase (ALT) levels was significantly greater at the time of appearance of second mutations (P = 0.0096). In most cases, wild-type HBV was mutated with the substitution of only rtM204I at first, and rtL180M/M204I mutations and then rtL180M/M204V mutations subsequently appeared. Further mutations of the polymerase region caused clinical deterioration. Thus as mutations emerge in the polymerase region, the clinical outcome deteriorates. Thus, monitoring the patterns of mutation of the polymerase gene is useful when using lamivudine for treating HBV.

Adult↗

Comparison between partial agonist (ME3412) and antagonist (alosetron) of 5-hydroxytryptamine 3 receptor on gastrointestinal function.

Therapeutic use of 5-hydroxytryptamine 3 (5-HT(3)) receptor antagonists for diarrhoea-predominant irritable bowel syndrome may be accompanied by constipation. We hypothesized that ME3412, 5-chloro-2-(1,4-diazacycloheptan-1-yl)-7-methylbenzoxazole, a novel partial agonist of the 5-HT(3) receptor, would minimize constipation without reducing antidiarrhoeal activity. Receptor binding studies showed that ME3412 is highly selective for the human 5-HT(3) receptor (K(i) = 1.51 nmol L(-1)). A 5-HT(3) receptor agonist, 2-methyl-5-HT, caused contractile response in the isolated guinea-pig ileum and accelerated secretion in the guinea-pig colonic mucosal preparation. ME3412 and 5-HT(3) receptor antagonist, alosetron, antagonized the 2-methyl-5-HT-induced responses with similar potency in insurmountable and surmountable manner, respectively. ME3412 caused weak agonism in isolated ileum strips and also in the colonic mucosa with intrinsic activity of 0.09 and 0.59, respectively. In conscious dogs, alosetron (3 microg kg(-1) i.v.) suppressed the migrating motor complex (MMC), whereas a relatively high dose (300 microg kg(-1)) of ME3412 was required for inhibition of MMC. ME3412 and alosetron suppressed 5-HT induced-diarrhoea in mice. In contrast, ME3412 did not significantly affect colonic propulsion compared with alosetron. These results imply that the partial agonist may relieve diarrhoea with low risk of inducing constipation.

Animals↗

Genetic diversity and phylogeny of Japanese sake-brewing rice as revealed by AFLP and nuclear and chloroplast SSR markers.

Japanese rice ( Oryza sativa L.) cultivars that are strictly used for the brewing of sake (Japanese rice wine) represent a unique and traditional group. These cultivars are characterized by common traits such as large grain size with low protein content and a large, central white-core structure. To understand the genetic diversity and phylogenetic characteristics of sake-brewing rice, we performed amplified fragment length polymorphism and simple sequence repeat analyses, using 95 cultivars of local and modern sake-brewing rice together with 76 cultivars of local and modern cooking rice. Our analysis of both nuclear and chloroplast genome polymorphisms showed that the genetic diversity in sake-brewing rice cultivars was much smaller than the diversity found in cooking rice cultivars. Interestingly, the genetic diversity within the modern sake-brewing cultivars was about twofold higher than the diversity within the local sake-brewing cultivars, which was in contrast to the cooking cultivars. This is most likely due to introgression of the modern cooking cultivars into the modern sake-brewing cultivars through breeding practices. Cluster analysis and chloroplast haplotype analysis suggested that the local sake-brewing cultivars originated monophyletically in the western regions of Japan. Analysis of variance tests showed that several markers were significantly associated with sake-brewing traits, particularly with the large white-core structure.

Analysis of Variance↗

The role of surgery in the treatment of brain metastasis: a retrospective review.

BACKGROUND: To study the role of surgery for brain metastasis, we reviewed the records of 646 patients with brain metastasis. METHODS: 340 patients underwent operative removal of the brain metastasis. During the same period, another 306 patients were treated without surgery. Criteria for surgery included the anatomical site, size over 3 cm, and cystic changes. Outcome was assessed by survival and cause of death. TREATMENT: 340 patients received surgical treatment, and 210 of these received radiation therapy. Another 306 patients were treated without surgery; 250 patients received conventional radiation and 56 patients were treated radiosurgically using a gamma knife. The surgical group was younger and had a better Karnofsky score than those of the non-surgical group. The median survival periods in the surgical and non-surgical groups were 21.0 months and 8.0 months, respectively. In patients whose brain lesions were first found before the systemic disease, the 5 year survival rates for the surgical and non-surgical groups were 35.2% and 18.2%, respectively. Although neurological causes accounted for 33.0% of deaths in the non-surgical group, and 13.2% of deaths in the surgical group; this difference was not significant. CONCLUSIONS: This retrospective review showed that patients with a brain metastasis treated surgically survived longer with better tumor control. To determine if this summary reflects the critical prognostic imbalance of population, further studies with randomized comparison are required.

Adult↗

From disease genes to cellular pathways: a progress report.

Mutations in a large number of retinal and retinal pigment epithelium (RPE) expressed genes can lead to the degeneration of photoreceptors and consequently the loss of vision. The genetic and phenotypic heterogeneity of retinal dystrophies poses a complex problem with respect to rational development of therapeutic strategies. Delineation of physiological functions of disease genes and identification of pathways that lead to disease pathogenesis represent essential goals towards developing a systematic and global approach to gene-based treatments. We are interested in identifying cellular pathways that are involved in photoreceptor differentiation, function and degeneration. We are, therefore, generating comprehensive gene expression profiles of retina and RPE of humans and mice using both cDNA- and oligonucleotide-based (Affymetrix) microarrays. Because of the under-representation of retinal/RPE genes in the public databases, we have constructed several unamplified cDNA libraries and produced almost twenty thousand expressed sequence tags (ESTs) that are being printed onto glass slides ('I-Gene' microarrays). In this presentation, we will report the microarray analysis of the rodless (and cone-enhanced) retina from the Nrl-knockout mouse as a paradigm to initiate the identification of cellular pathways involved in photoreceptor differentiation and function.

DNA-Binding Proteins↗

Which infertile women should be indicated for sonohysterography?

OBJECTIVE: To evaluate the indications for transvaginal saline contrast sonohysterography (TV-SCSH) in endometrial screening by transvaginal sonography in infertile women. METHODS: The study involved 850 consecutive infertile women presenting to an outpatient clinic. Using transvaginal ultrasound endometrial images were evaluated in the proliferative phase. Abnormal images were classified as follows: rugged (R), hyperechoic (H), waved (W), or thick (T). Clinical symptoms such as hypermenorrhea, dysmenorrhea and abnormal uterine bleeding were also recorded. Abnormal endometrial images were further evaluated on TV-SCSH. Age-matched women with normal endometrial images underwent TV-SCSH as controls. RESULTS: The endometrial pattern was abnormal in 111 patients (13.1%). Lesions that had been identified by TV-SCSH including endometrial polyps (44 cases), submucosal myomata (29 cases), and intramural myomata with mucosal extension (24 cases) were largely associated with the R and/or the H pattern, the W or the T pattern, and the W pattern, respectively. Sensitivity and specificity of the abnormal endometrial image for any lesion were 100% and 91.5%, respectively. Sixty-four patients (59.3%) were asymptomatic despite an abnormal endometrial image. CONCLUSIONS: TV-SCSH should be performed on selected patients following assessment of endometrial images on transvaginal sonography in order to diagnose intra- and pericavitary lesions in infertile women.

Adult↗

Effects of temperature, atmosphere and pH on the generation of smoke compounds during tobacco pyrolysis.

The pyrolysis of tobacco under a variety of conditions was performed to examine the generation profiles of 29 known toxic compounds in tobacco smoke (hydrogen cyanide, benzo[a]pyrene, aldehydes, volatile organic compounds, phenolics, aromatic amines, etc.). The generation profiles of smoke compounds varied according to three conditions: the pyrolysis temperature (300-1000 degrees C), the pyrolysis atmosphere (in nitrogen and air) and pH of the tobacco leaf (2.89-7.07). Most of the smoke compounds (28 compounds) were generated primarily at temperatures less than 800 degrees C. More than half of the smoke compounds (17 compounds) were unaffected by the type of atmosphere, and seven compounds were significantly affected by pH. These results can provide basic and useful information to further study on the formation mechanisms and the technology involved in the control of smoke generation.

Hot Temperature↗

Equilibrium of radiocesium with stable cesium within the biological cycle of contaminated forest ecosystems.

Concentrations of (137)Cs and stable Cs were determined in plant, mushroom, lichen and soil samples collected at two forest sites with different contamination levels in Belarus in 1998. The concentration of (137)Cs in soil was the highest in near-surface organic layers (Of and Oh horizons) and decreased with depth in the mineral layers, whereas the concentrations of stable Cs were almost constant in the soil profile. The levels of (137)Cs and stable Cs in biological samples varied depending both on the species and the plant part sampled. Even though different species and parts of the same species were included, the concentration ratios of (137)Cs to stable Cs were fairly constant for samples collected at the same forest site, and were in the same order of magnitude as the (137)Cs to stable Cs ratios for the organic soil layers. This finding suggests that (137)Cs, mainly deposited on the forest ecosystems from the Chernobyl accident in 1986, was well mixed with stable Cs within the biological cycle in the forest ecosystems by 1998. The transfer factor for each biological sample of (137)Cs was almost the same as that of stable Cs, if they were calculated based on the concentrations in the Of + Oh layer. This suggests that the stable-Cs-based transfer factor could be used as equilibrium transfer factor of (137)Cs for different types of biological samples in the forest.

Agaricales↗

A new computer-assisted method for measuring the tibio-femoral angle in patients with osteoarthritis of the knee.

OBJECTIVE: The purpose of this study was to evaluate the inter- and intraobserver variability in measuring the tibio-femoral angle using our new computer-assisted method, and to compare it with a conventional manual method. METHODS: Radiography of all patients of osteoarthritis of the knee in outpatient were performed with standing on both legs, and with conventional antero-posterior weight bearing view of the knee fully extended. Three examiners measured the tibio-femoral angle with the computerized method in 52 subjects with osteoarthritis (73 knees). The tibio-femoral angle was measured using a computer-assisted method in which the observer must visually determine and select eight points on the margins of the femur and tibia on a radiographic image displayed on a computer monitor. The inter- and intraobserver Intra-class correlation (ICC) was analyzed. RESULTS: The interobserver mean correlation of computer-assisted method was 0.970 with a mean difference of 0.38 degrees (S.D. 1.125 degrees). The intraobserver mean ICC of computer-assisted method was 0.973, with a mean difference of 0.16 degrees (S.D. 1.12 degrees). An analysis of the difference between conventional methods and our new system showed a mean ICC of 0.922, with an intersystem mean difference of 0.295 degrees (S.D. 1.82 degrees). CONCLUSION: Our computer-assisted method of measuring the tibio-femoral angle was simple, easy, and quick, and should be considered as an alternate method for measurement.

Adult↗

Chromoendoscopy using indigo carmine dye spraying with magnifying observation is the most reliable method for differential diagnosis between non-neoplastic and neoplastic colorectal lesions: a prospective study.

BACKGROUND AND AIMS: Differential diagnosis between non-neoplastic and neoplastic lesions is very important at colonoscopy, since removal or biopsy of non-neoplastic polyps wastes time and resources. We therefore conducted a prospective study to examine whether indigo carmine dye spraying with and without magnification is more reliable than the conventional method for differential diagnosis. PATIENTS AND METHODS: 122 patients with 206 lesions of 10 mm or smaller were recruited into this study. All lesions detected on colonoscopy were first diagnosed using the conventional view, then at chromoendoscopy using 0.2 % indigo carmine, and finally at chromoendoscopy with magnification. The diagnosis at each step were recorded consecutively. All lesions were finally categorized as neoplastic or non-neoplastic according to pit pattern; non-neoplastic lesions were biopsied for histological evaluation, and all the neoplastic ones were removed endoscopically. The accuracy rate of each type of endoscopic diagnosis was evaluated, using histological findings as reference. RESULTS: Histologically, 46 lesions (22 %) were non-neoplastic and 160 (78 %) were neoplastic. The overall diagnostic accuracies by conventional view, chromoendoscopy, and chromoendoscopy with magnification were 84.0 % (173/206), 89.3 % (184/206) and 95.6 % (197/206), respectively. CONCLUSION: Chromoendoscopy with magnification is the most reliable method for determining whether a colorectal lesion is non-neoplastic or neoplastic.

Adult↗