Biomedical subjects

Y Matsui

Publications and source records attributed to Y Matsui.

At least 73 records · Page 4Linked to original sources

PubMed2001

Loss of the SEDL gene product (Sedlin) causes X-linked spondyloepiphyseal dysplasia tarda: Identification of a molecular defect in a Japanese family.

A 23-year-old man was diagnosed as having X-linked spondyloepiphyseal dysplasia tarda (SEDT; MIM 313400) based on his disproportionately short trunk, short stature, characteristic radiological features of the spine (posterior hump, end plate sclerosis, and disc space narrowing) and the hips (short and thick femoral necks), and positive family history. This Japanese family was found to have an intragenic deletion flanking intron 2 and exon 3 of the SEDL gene that not only included the 5' untranslated region but also the coding sequence for the first methionine through the 25th alanine. This mutation was present in the proband and his unaffected mother (a heterozygote), but not in an unaffected sister and an unaffected uncle. The nature of the mutation predicted that the SEDL protein (Sedlin) was not produced in the proband, indicating that loss of Sedlin caused SEDT.

Adult↗

PubMed2001

Perioperative blood transfusion in hepatocellular carcinomas: influence of immunologic profile and recurrence free survival.

BACKGROUND: The postoperative recurrence of hepatocellular carcinomas (HCC) associated with perioperative blood transfusion has been the subject of controversy. The authors prospectively investigated the relation between perioperative allogeneic blood transfusions, the recurrence free survival, and the immunologic profiles of patients with HCC who had undergone curative hepatic resections. METHODS: One hundred eight patients were divided into two groups: a transfused group (n = 53) and a nontransfused group (n = 55), according to their perioperative transfusion history. The subsets of lymphoid cells, natural killer cell activity and the phytohemagglutinin (PHA) response were all measured preoperatively, and at 1, 2, and 4 weeks and at 3 and 6 months after the hepatectomy. The recurrence free survival rate then was compared between these two groups. RESULTS: There were no significant differences between these two groups with respect to histologic findings, clinical stage, type of resection, pathologic data, and the recurrence free survival rate. Postoperative levels of the CD8 in the transfused group were elevated as compared with the nontransfused group, and the PHA response of the transfused patients was significantly increased at 7 postoperative days. Natural killer cell activity of the transfused patients was decreased at 7 postoperative days, as compared with the nontransfused patients, but there was no significant difference. CONCLUSIONS: Although allogeneic blood transfusion may have immunosuppressive effects, perioperative blood transfusions did not influence the cancer free survival rate in patients with hepatocellular carcinoma.

Adult↗

PubMed2001

Bcl-2 inhibits apoptosis of spermatogonia and growth of spermatogonial stem cells in a cell-intrinsic manner.

The growth, differentiation, and death/survival of spermatogonia are precisely regulated for the proper production of spermatozoa. We have previously shown that Bcl-2 ectopically expressed in spermatogonia caused the inhibition of normal spermatogonial apoptosis and the subsequent failure of differentiation in transgenic mice. In addition, the growth of spermatogonial stem cells seemed to be temporally arrested in the transgenic mice. In the present study, we attempted to examine whether the abnormality of spermatogonia described above was caused by Bcl-2 misexpression in the spermatogonia or by an abnormal spermatogenic environment of the transgenic mice. We transplanted testicular cells of transgenic mice to seminiferous tubules of W/Wv mice in which transplanted normal testicular cells can undergo spermatogenesis. We found that the transplanted spermatogonia of the transgenic mice reproduced a series of abnormal changes including temporal growth arrest of spermatogonial stem cells and abnormal accumulation of spermatogonia in tubules, which were also observed in the testes of the transgenic mice. The results indicated that Bcl-2 inhibited apoptosis of spermatogonia and growth of spermatogonial stem cells in a cell-intrinsic manner. We also cultured testicular cells of transgenic mice and found that the spermatogonia of the transgenic mice were better able to survive than were those of wild-type mice but that their differentiation was not affected. The result suggested that failure of differentiation of the accumulated spermatogonia in the transgenic testes is not due to the abnormality of the bcl-2 misexpressing spermatogonia, but may be caused by extrinsic problems including improper interaction of spermatogonia with supporting cells.

Animals↗

PubMed2001

High incidence of severe urologic complications following radiotherapy for cervical cancer in Japanese women.

BACKGROUND: Good results have been obtained with radiation therapy for cervical cancer, but many patients suffer radiation-induced complications of adjacent organs. Some authors have reported that about 10% of patients treated with radiotherapy experience radiation-induced complications. We have previously reported that the incidence of spontaneous rupture of the urinary bladder is high in Japan but extremely low in the United States and Europe. In this study, we examined whether incidence or type of radiation-induced complications differs between Japan and the United States and Europe. METHODS: A retrospective study was performed to determine the incidence among Japanese women of severe complications requiring surgical intervention following radiotherapy for cervical cancer. A total of 271 patients were treated at Kobe City General Hospital using external-beam therapy from December 1981 to March 1989. In 232 external-beam therapy was combined with high-dose-rate intracavitary brachytherapy with a remotely controlled afterloading system (RALS). The incidence and type of radiation-induced complications of the urinary tract, rectum, and intestine were determined following exclusion of 74 patients with evidence of disease recurrence or progression. RESULTS: A total of 16 patients (8.1%) had urologic complications that required surgical intervention following irradiation, while a total of 26 patients (13.2%) had complications of the rectum or intestine that required surgical intervention following irradiation. Urologic complications occurred significantly later than those of the rectum and intestine (6.4 and 2.2 years, respectively) (P < 0.0001). The overall incidence of severe complications was comparatively higher than reported in the United States and Europe. The incidence of spontaneous rupture of the urinary bladder was particularly high (2.0%) in Japan. CONCLUSIONS: The incidence of severe complications following radiotherapy is comparatively higher in Japan than in the United States and Europe. In particular, spontaneous rupture of the urinary bladder is common in Japan. This might be due to the use of high-dose-rate brachytherapy. Since brachytherapy is currently being used for prostate cancer, urologists and radiologists must consider the possibility of a high incidence of such severe complications, especially when using high-dose-rate brachytherapy.

Brachytherapy↗

PubMed2001

Removal of a synthetic organic chemical by PAC-UF systems--I: Theory and modeling.

Based on the age distributions of powdered activated carbon (PAC) in reactors, the competitive bi-solute isotherm and the pore-surface diffusion mechanism, a model was developed to predict the removal of a trace synthetic organic chemical (SOC) when PAC was applied to an ultrafiltration (UF) membrane system. Independent experiments evaluated the input parameters for the model. The pore diffusion in liquid-filled pore was the dominant internal mass transfer mechanism in a PAC particle and the surface diffusion mechanism was neglected in the model. Model prediction was compared with data from pilot plant experiments treating simazine in natural water. Due to the blending and the increasing PAC in the UF loop, a transient behavior of effluent simazine concentration was observed in the UF effluent. The model predicted successfully this periodical variation of the simazine concentration in the UF loop effluent, as well as the simazine concentration in the effluent from the PAC slurry contactor. The faithful model prediction required the modeling of the phenomenon of adsorption/desorption of an SOC on membrane itself.

Adsorption↗

PubMed2001

Removal of a synthetic organic chemical by PAC-UF systems. II: Model application.

This paper describes several application potentials with a recently developed model for predicting the synthetic organic chemical (SOC) removal by powdered activated carbon (PAC) adsorption during ultrafiltration (UF) and discusses the removal mechanism. The model was successfully applied, without any modification, to dead-end mode operation as well as to cross-flow mode operation, validating the assumption of the internal diffusion control mechanism and the continuously-stirred-tank-reactor (CSTR) concept. Even when UF was operated in a cross-flow mode, PAC added was re-circulating in suspension for only a short time. Then, solute uptake took place mostly by PAC immobilized in membrane tubes not only for dead-end operation but also for cross-flow operation. Therefore, cross-flow operation did not have any advantage regarding the SOC mass transfer on PAC in UF loop over dead-end operation. The model simulation implied that pulse PAC addition at the beginning of filtration cycle resulted better SOC removal than continuous PAC addition. However, for the pulse PAC addition mode, the model predicted somewhat lower effluent SOC concentration than the observed values, and the benefit of pulse PAC application in terms of reducing SOC over its continuous dosage was not confirmed. Longer detention time of PAC dosed in a pulse than continuously dosed PAC could possibly further decrease internal diffusivity.

Charcoal↗

PubMed2001

The variation on the mutagenicity of CNP during anaerobic biodegradation.

The mutagenicity of water, including herbicide CNP, and its time-variation during anaerobic biodegradation were studied through Ames assay using strains with or without. S9 mix: TA98, TA 100, YG1021, YG1024, YG1026, and YG1029. The bacteria, for the anaerobic biodegradation, was obtained from a paddy field, and preincubated for a month. The CNP was decomposed in an anaerobic culture inoculated with the bacteria, and finally yielded CNP-amino as one of the CNP metabolites. About 16% of the initial CNP was transformed into CNP-amino by the 14th day. The mutagenicities to TA98. YG1024, and YG1029 strains with S9 mix increased with cultivating time, the latter two showed the strongest sensitivity to CNP-amino. The contribution of CNP to the mutagenicity decreased as the chemical decomposed, while the contribution of CNP-amino increased. However, the increased mutagenicity was not limited to the contribution of CNP-amino. but also to the contribution of other metabolites. The contributions of other CNP metabolites were 67% of total mutagenicity to the TA98 strain and 30% to the YG1029 strain. These unknown mutagenic metabolites were the indirect frameshift mutagens which did not have nitro- and amino-substituents, and the indirect base-pair mutagens which might possibly have some amino-substituents.

Anaerobiosis↗

PubMed2001

The effects of transplantation of osteoblastic cells with bone morphogenetic protein (BMP)/carrier complex on bone repair.

We investigated the effects of transplantation of osteoblastic cells with a bone morphogenetic protein (BMP)/carrier complex on bone repair by in vitro and in vivo experiments. Poly-D,L-lactic-co-glycolic acid/gelatin sponge (PGS) was used as a carrier for cell transplantation. In the in vitro experiments, three cell types, C3H10T1/2 cells, MC3T3-E1 cells, and primary osteoblastic cells, isolated from newborn rat calvariae (ROB cells), were cultured for 2 weeks on PGS alone or PGS containing BMP-2 (PGS/BMP). C3H10T1/2 cells cultured on PGS/BMP expressed several markers related to differentiation of both osteoblasts and chondrocytes, such as alkaline phosphatase (ALP) activity and mRNAs for osteocalcin and aggrecan, whereas the cells cultured on PGS alone expressed no such markers. MC3T3-E1 cells cultured on PGS/BMP exhibited a more ALP-positive cells than those cultured on PGS alone. PGS/BMP promoted ROB cell differentiation into both osteoblasts and chondrocytes. In the in vivo experiments, we transplanted ROB cells, which had been cultured on PGS alone or PGS/BMP in vitro for 2 weeks, into bone defects created in rat calvariae. Transplantation of ROB cells cultured on PGS alone generated little new bone. Transplantation of ROB cells cultured on PGS, which absorbed a low dose (10 ng) of rhBMP-2,; induced significantly higher bone mineral content than PGS/BMP alone, although application of a high dose (1 microg) of rhBMP-2 induced no difference in bone mineral content between transplantation of PGS/BMP with or without ROB cells. These results show that transplantation of osteoblastic cells after induction of osteoblast maturation in vitro by cultivation on PGS/BMP is a potent technique for cell therapy of bone repair.

Aggrecans↗

PubMed2001

Skeletal development of achondroplasia: analysis of genotyped patients.

BACKGROUND: Achondroplasia is a skeletal dysplasia caused by substitution of arginine for glycine at codon 380 (G380R) mutation of the fibroblast growth factor receptor 3. To date, the developmental course of the phenotype (short stature and skeletal characteristics) has not been clarified in the genotyped population. METHODS: The relationship between age and clinical data (height, arm span and measurements of skeletal radiographs) were statistically analyzed from 27 achondroplasia patients with the G380R genotype. RESULTS: The height standard deviation score had positive correlation and decreased with age, while span-to-height ratio did not. Among measurements of skeletal radiographs, the pelvic index, which represents the squared pelvis deformity, were correlated and increased with age. However, interpedicular distance of the first and fourth lumbar vertebrae (L1:L4) ratio as an index for the caudally narrowed pattern of the lumbar spinal canal and fibula-to-tibia ratio for the disproportionally long fibulae were not correlated and did not increase with age. CONCLUSION: In making a clinical diagnosis of achondroplasia in early infancy, it should be noted that short stature and squared pelvis deformity are not prominent.

Achondroplasia↗

PubMed2001

Ureteroarterial fistula in a patient with a single functioning kidney.

A rare case is reported of a fistula between the left internal iliac artery and the left ureter in a patient whose left kidney was the only functioning kidney. Internal iliac artery embolization was initially successful in stopping the bleeding, but the fistula recurred when the ureteral stent was removed. Even after embolization, the tissue surrounding a fistula remains very fragile, so the fistula may easily recur as a result of slight injury or inflammation.

Aged↗

PubMed2001

A histomorphometric study of the tissue reaction around hydroxyapatite implants irradiated after placement.

PURPOSE: The tissue reaction around hydroxyapatite (HA) implants irradiated at 3 different time points after placement was histologically and histomorphometrically analyzed to further determine the relation between irradiation and tissue reaction. MATERIALS AND METHODS: Cylindrical high-density HA implants were placed in the mandibles of 48 Japanese white rabbits. The mandible was then irradiated with a single 15-Gy dose 5, 14, or 28 days after implantation. The rabbits were sacrificed on days 7, 14, 28, or 90 after irradiation. Nonirradiated rabbits with implants were used as controls. Nondecalcified specimens stained with toluidine blue were used for histologic analysis and histomorphometric measurements. RESULTS: In the rabbits irradiated 5 days after implantation, the HA-bone contact occurred later than in the controls. The bone-implant contact surface ratio was lower than in the controls at each time of sacrifice because of necrosis of the newly formed bone just after irradiation. The HA-bone contact in rabbits irradiated 14 and 28 days after implantation was similar to that of the controls. Bone remodeling was suppressed in the rabbits in each group sacrificed 90 days after irradiation. CONCLUSIONS: Therapeutic irradiation shortly after implantation inhibits direct contact between the HA implant and the surrounding bone. Bone contact occurring before irradiation was minimally affected. Regardless of the interval between implantation and irradiation, postimplantation irradiation inevitably delays bone remodeling.

Animals↗

PubMed2001

Human atrial natriuretic peptide is a useful criterion in treatment of nocturia.

BACKGROUND: Nocturia is one of the major problems of elderly people. The possible causes of nocturia include irritation of lower urinary tract obstruction, disturbance of the fluid balance, and sleep disturbance. In a significant proportion of patients, the mechanism of nocturia is still unclear and a definitive method of treatment has yet to be determined. This study investigated how to treat nocturia. MATERIALS AND METHODS: We analyzed 51 patients who visited Kobe City General Hospital between January 1998 and June 1999 with nocturia (three or more nocturnal voidings) and no daytime urological problems. Twenty-two of these patients were given daytime diuretic therapy (azosemide 60 mg), while 29 other patients received a minor tranquilizer. The method of treatment was selected randomly. Correlations between the plasma level of atrial natriuretic peptide (hANP) and the effect of treatment were analyzed. RESULTS: Daytime diuretics decreased the nocturnal frequency of voiding in 10 out of 22 patients. The plasma hANP level at the first visit was significantly higher in the patients with improvement (p = 0.0026). Furthermore, the plasma hANP level was significantly decreased after daytime diuretic therapy in patients who showed improvement of nocturia with diuretic therapy (p = 0.0180). Minor tranquilizer administration decreased nocturia in 22 out of 29 patients. The plasma hANP level at the first visit was significantly lower in the patients who improved (p = 0.0021). CONCLUSIONS: These findings suggest that patients with higher plasma hANP levels should be treated as having subclinical heart failure, while nocturia in patients with a normal plasma hANP level might be caused by sleep disturbance.

Aged↗

PubMed2001

Light element analysis in oxycarbonate superconductors using EELS.

Elemental analysis in an oxycarbonate superconductor ((Cu,N,C)Sr2CaCu2Oy) is conducted using transmission electron microscope-electron energy-loss spectroscopy with detector-gain correction. The gain correction enables highly sensitive elemental analysis and precise measurement of energy-loss near edge structures (ELNESs). It is found that carbon is included as a CO3 group, because the carbon K-edge in the oxycarbonate shows the same ELNES observed from CaCO3. Nitrogen ELNES is similar to that of Sr(NO3)2, so nitrogen is contained as a NO3 group. Although both CO3(2-) and NO3- have similar planar atomic arrangements, the nitrogen ELNES observed is different from that of carbon. EEL spectrum simulation based on DV-Xalpha method is used to interpret the difference.

Journal Article↗

PubMed2001

Fourier images feature of lattice fringes formed by low-loss electrons as observed using spatially-resolved EELS technique.

The lattice fringes of inelastically scattered electrons were investigated using spatially-resolved electron energy-loss spectroscopy (EELS) technique. The intensity profiles of lattice fringes formed by low-loss electrons were observed, and their position and contrast were elucidated with high spatial resolution. It was found that the conventional transmission electron microscope image includes low-loss images, which are the integrated image of through-focus images weighted by the intensity of the EEL spectrum. The modulation feature in the lattice fringes of inelastically scattered electrons is similar to the Fourier images. It means that the exit wave field of elastically scattered electrons is almost preserved in that of low-loss electrons.

Journal Article↗

PubMed2001

HRTEM study of new series of oxycarbonitrate superconductors (Cu,C,N)Sr2Ca(n - 1)Cu(n)O(y) (n = 1-6).

Arrangements of Cu and anion groups (CO3 and NO3) in the charge-reservoir (CR) blocks of a series of new oxycarbonitrate superconductors (Cu,C,N)Sr2Ca(n - 1)Cu(n)O(y) (n = 1-6) were examined by means of electron diffraction and high-resolution transmission electron microscopy (HRTEM). The first three members with n = 1-3 [Tc = 33 K (n = 1), 91 K (n = 2), 90 K (n = 3)] show the 4a0-type superstructures with periodic arrangements, [-Cu-X-X-X-Cu-X-X-X-Cu-] (X = CO3, NO3), in the CR blocks. The third member (n = 3) partly contains the 2a0-type of superstructure with [-Cu-X-Cu-X-Cu] in the CR blocks. The fourth member with n = 4 (Tc = 113 K) contains only the 2a0-type of superstructure. The higher members, with n = 5 (Tc = 65 K) and n = 6 (Tc = 52 K), show no evidence of ordering in the CR blocks, suggesting random arrangements of Cu and anion groups.

Journal Article↗

PubMed2001

Spatially-resolved EELS analysis of multilayer using EFTEM and STEM.

Spatially-resolved electron energy-loss spectroscopy (EELS) is applied to the multilayer (SiO2/Si3N4/SiOxNy/Si), a common semiconductor device structure. To observe depth profile at sub-nanometre spatial resolution, scanning transmission electron microscopy (STEM) and energy-filtering transmission electron microscopy (EFTEM)-based techniques are compared in practical application. STEM-based EELS is useful in simultaneously analysing plural elements. EFTEM-based EELS is suitable for analysing the chemical shift and core loss intensity of single element. The practical spatial resolution is of the same order for each technique, both involving beam damage, which can be reduced by decreasing current density in EFTEM and avoiding beam overlapping in STEM.

Journal Article↗

PubMed2001

Effects of p53 mutations on cellular sensitivity to ionizing radiation.

Mutations in the p53 tumor suppressor gene have been found in more than 50% of human tumors including those in breast, colon, lung, and oral cavity. However, the significance of p53 mutation in radiation sensitivity and its underlying mechanisms still remains unclear. In this study, we have measured the effects of p53 mutation on cell cycle delay, apoptosis, and radiation sensitivity using mouse cells transfected with different forms of p53 mutations. Wild-type p53 and p53-Null mouse embryo fibroblast cells were used as positive and negative controls, respectively. Exponentially growing cells were irradiated with 0- to 9-Gy gamma rays and then assayed for cell survival, p53 expression, cell cycle checkpoint, and apoptosis. Cell survivals determined by clonogenic assay show that p53 mutant cells are generally more sensitive to ionizing radiation than cells with wild-type p53. Western blot analysis indicates that exposure to 6-Gy gamma rays increases the p53 expression levels by two- to threefold in wild-type p53 cells. However, the p53 level remains unchanged in cells with mutant p53 during the same postirradiation period. Irradiation with 6-Gy gamma rays produces G2/M arrest in all cell lines, indicating that p53 is probably not involved in the G2/M checkpoint. However, all mutant cells fail to show any significant G1/S arrest after irradiation, suggesting that G1/S arrest may be implicated in radiation sensitivity. Finally, there is very little apoptosis (<3% by Tat-mediated dUTP nick-end labeling [TUNNEL] and morphologic assays) detected in wild-type and p53 mutant cell lines after 6-Gy gamma rays. Our results suggest that mutant forms of p53 represent a phenotype that affects the radiation sensitivity and is not dependent on the apoptotic pathway.

Animals↗

PubMed2001

Functional hepatic volume measured by technetium-99m-galactosyl-human serum albumin liver scintigraphy: comparison between hepatocyte volume and liver volume by computed tomography.

OBJECTIVES: We investigated the usefulness of measuring the functional hepatic volume by single-photon emission CT with 99m-technetium galactosyl-human serum albumin scintigraphy (GSA-LV). We then compared this value to the total hepatocyte volume and the hepatic volume determined from CT (CT-LV) in the patients with hepatobiliary tumors. METHODS: Forty-seven patients were divided into two groups, the SM group (subsegmentectomy and monosegmentectomy) and the DT group (disegmentectomy and trisegmentectomy). These groups were further divided into subgroups with or without chronic hepatitis or cirrhosis. The GSA-LV, CT-LV, and the total hepatocyte volume were then calculated. The GSA-LV and CT-LV measurements were performed preoperatively, at 2 and 4 wk, and at 3 and 6 months after surgery. RESULTS: The preoperative GSA-LV values were significantly correlated with the hepatocyte volume and the 15-min retention rate of indocyanine green (ICGR15). Similarly, the hepatocyte volume correlated well with the CT-LV and ICGR15. However, the CT-LV was correlated only with the ICGR15. Recovery of the GSA-LV in the DT group was delayed, and about 90% of the volumetric and functional regeneration was observed within 6 months after the hepatectomy. In contrast, the CT-LV of DT group patients with normal liver remnants returned to approximately 90% of their initial volume within 1 month after the hepatectomy, whereas patients with injured livers regenerated gradually and regained approximately 80% of their preoperative value by 6 months after the hepatectomy. CONCLUSIONS: We conclude that the measurement of functional hepatic volume using the GSA-LV is useful in fully evaluating hepatic function based on hepatocyte volume.

Bile Duct Neoplasms↗