Biomedical subjects

T Matsunaga

Publications and source records attributed to T Matsunaga.

At least 55 records · Page 3Linked to original sources

PubMed2001

Mammary ductoscopy for diagnosis and treatment of intraductal lesions of the breast.

BACKGROUND: Mammary ductoscopy (mammoscopy) is an ideal diagnostic method for intraductal lesions. The usefulness of mammoscopy for intraductal lesions was evaluated. METHODS: Mammoscopy was performed in 315 cases with nipple discharge. The mammoscopic findings of 46 breast cancer cases (47 lesions) and 109 intraductal papilloma cases (119 lesions) were compared with pathological findings. RESULTS: Carcinoma was recognized by mammoscopy in 38 of 47 lesions (80.9%). Intraductal masses were detected by mammoscopy in 115 of 119 intraductal papilloma lesions. The shape of the mass was classified as hemispheric, papillary, or flat protrusion. The hemispheric and papillary shapes were most common in cases of intraductal papilloma and the flat protrusion type was most common in cases of carcinoma. The amount of material collected by intraductal biopsy under mammoscopic observation was smaller in carcinoma than in intraductal papilloma because the carcinoma lesions were usually located in peripheral duct-lobular units and had weak tissue cohesion compared with that of intraductal papilloma. Of 133 intraductal biopsies performed for 69 intraductal papillomas, 17 biopsies yielded material insufficient for diagnosis in. The effectiveness of treatment by intraductal biopsy was recognized in 38 of 46 intraductal papillomas in which clinical follow-up continued for more than two years (82.6%). The therapeutic results of biopsy were poor in cases of multiple intraductal masses in multiple duct-lobular units. CONCLUSIONS: Mammoscopy contributes not only the diagnosis in cases of nipple discharge, but is also of benefit in the treatment of intraductal papilloma.

Breast Neoplasms↗

PubMed2001

Long-term survival and late-onset complications of cancer patients treated with high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation.

The antitumor effect of high-dose chemotherapy (HDC) followed by autologous peripheral blood stem cell transplantation (auto-PBSCT) is considered superior to that of conventional chemotherapy. However, the long-term benefits of this strategy in Japan remain unclear. Therefore, in this study, 109 cancer patients enrolled between 1989 and 1999 were treated with HDC and auto-PBSCT. Patients were evaluated for long-term survival and late-onset complications, including secondary malignancy. The mean number of CD34+ cells harvested per apheresis was larger in the group receiving high-dose cytosine arabinoside or high-dose etoposide plus granulocyte colony-stimulating factor (G-CSF) than in the group receiving conventional chemotherapy plus G-CSF. The 5-year overall survival rates for non-Hodgkin's lymphoma patients in first complete remission (CR) (83.2%), second or subsequent CR (74.1%), or first partial remission (PR) (66.7%) at the time of transplantation were significantly higher than those with no remission (35.7%) at the time of transplantation (first CR, P < .05; second or subsequent CR, P < .05; first PR, P < .05). The 5-year overall survival (OS) rates for breast cancer was 40.8%, and the disease-free survival rate was extremely low (8.8%). The 5-year OS rates for chemotherapy-sensitive and chemotherapy-resistant diseases at the time of transplantation were 32.7% and 35.7%, respectively, a difference that was not considered significant. The 5-year OS for germ cell tumor was 80.0%, and the disease-free survival rate was 77.9%. The rate of therapy-related death was 8.2%. The occurrence rate of secondary malignancy was 0.9%. Late-onset complications were observed in 4 cases (glomerulonephritis, interstitial pneumonitis, ulcerative colitis, and acute myelogenous leukemia). At 3.7%, the occurrence rate was not very high, but most complications of auto-PBSCT were life threatening and interfered with patients' quality of life. A careful follow-up is required for at least 2 years after transplantation, because the mean occurrence time of late-onset complications is 16.7 months posttransplantation.

Adult↗

PubMed2001

Strangulated umbilical hernia in a child: report of a case.

Most umbilical hernias in children close spontaneously. Complications associated with umbilical hernias are rarely observed during follow-up. We report herein a 5-month-old girl with a strangulated umbilical hernia. Her umbilicus was hard, reddish, and irreducible. Plain radiography of the abdomen showed signs of mechanical ileus. The patient was thus diagnosed to have a strangulated umbilical hernia. A 5-cm section of the ascending colon and a 5-cm section of the terminal ileum, as well as the cecum and appendix, were congested, edematous, and erythematous, and together were enclosed by a firm hernial ring. A closure of the fascial defect and umbilicoplasty were performed. The postoperative course was uneventful. In patients with infantile umbilical hernias, strangulation may occur as the fascial defect decreases in size.

Constriction, Pathologic↗

PubMed2001

Yohimbine increases the binding potential for [11C]flumazenil in the monkey brain.

We evaluated the impact of yohimbine administration on benzodiazepine (BDZ) receptor binding in the central nervous system of non-human primates (rhesus monkeys). Estimates of the binding potential (Bmax/Kd) of BDZ receptors were made following intravenous administration of yohimbine, an alpha2-adrenoceptor antagonist. Positron emission tomography was used in conjunction with [11C]flumazenil (Ro 15-1788), a tracer for central BDZ receptor binding activity. The effects of yohimbine were compared with a control condition in which saline was administered. Yohimbine significantly increased the binding potential in the hippocampus, as assessed using a Student's t-test with Bonferroni correction. The result that the administration of yohimbine readily induces an increase in the binding potential for BDZ receptors in the primate brain suggests that the presence of an anxiety state potentiates the effect of anxiolytics.

Adrenergic alpha-Antagonists↗

PubMed2001

Pectic polysaccharide rhamnogalacturonan II is covalently linked to homogalacturonan.

A borate-containing pectin was solubilized from sugar beet (Beta vulgaris L. ) cell walls by treatment with 0.5 M imidazole, pH 7. The molecular weight of the pectin was reduced when the borate ester was hydrolyzed by treatment with 1 N HCl. Treatment of the acid-treated pectin with boric acid in the presence of Pb(2+) gave a product whose molecular weight distribution was similar to the imidazole-soluble pectin. The imidazole-soluble pectin was saponified and then digested with endo- and exo-polygalacturonases. These treatments shifted the boron peak at the high molecular weight region to the low molecular weight (10 kDa), which corresponds to rhamnogalacturonan II-borate ester cross-linked dimer (dRG-II-B). The treatment also generated rhamnogalacturonan I (RG-I), dRG-II-B, monomeric rhamnogalacturonan II and galacturonic acid. These results show that imidazole solubilizes a high molecular weight borate-containing pectic complex composed of homogalacturonan-rhamnogalacturonan II and RG-I. Our data suggest that borate esters formed between rhamnogalacturonan II molecules cross-link the macromolecular pectin.

Borates↗

PubMed2001

Detection of HbA(1c) by boronate affinity immunoassay using bacterial magnetic particles.

We have developed a boronate affinity immunoassay system using m-aminophenylboronic acid (mAPB) coupling to bacterial magnetic particles (BMPs). Homobifunctional crosslinker, Bis-(succcimidyl)suberate (BS3), was employed for preparation of mAPB-BMPs conjugates (mAPB-BMPs). Quantities of HbA(1c) on mAPB-BMPs were evaluated based on luminescence from alkaline phosphatase-conjugated anti-Hb antibody (ALP-antibody) binding to HbA(1c) on the BMP surface. The binding of HbA(1c) to mAPB-BMPs occurred gradually and was almost completed within 10 mm. The coupling reaction is enhanced due to static electric interaction between the positive charges on HbA(1c) and negative charges on BMPs. The amount of HbA(1c) binding to mAPB-BMPs increased with increasing sodium chloride concentrations in the range of 0-100 mM. However, the amount of Hb binding to mAPB-BMPs also increased in high concentration of sodium chloride. The Hb binding to mAPB-BMPs was detached from mAPB-BMPs when Hb-mAPB-BMPs were washed with low salt buffer. This indicates that Hb is nonspecifically adsorbed onto the surface of mAPB-BMPs in high concentration of sodium chloride. These results suggest that selective separation of HbA(1c) using mAPB-BMPs can be achieved with these conditions. A dose-response curve was obtained between luminescence intensity and HbA(1c) concentration using a fully automated boronate affinity immunoassay. A linear relationship between luminescence intensity and HbA(1c) concentration was obtained in the range of 10-10(4) ng/ml.

Alkaline Phosphatase↗

PubMed2001

Construction of electrochemical flow immunoassay system using capillary columns and ferrocene conjugated immunoglobulin G for detection of human chorionic gonadotrophin.

In this paper is reported a miniaturized flow immunoassay system. Ferrocenecarboxylic acid (Fc) conjugated with anti-HCG immunoglobulin G (IgG) antibody (Fc-IgG) was prepared, and used as a novel analytical reagent. The system consists of the immunoreaction section, the capillary column packed with cation exchange resin, and the flow cell for electrochemical detection of Fc-IgG. Antibody-antigen complexes were separated from their free conjugate on the basis of differences in isoelectric point (pI) using a cation exchange capillary column. The assay yielded a linear relationship between signal and HCG concentration in the range 0-2000 mIU/ml. This simple technique enables the assay of HCG within 2 min. The cation exchange capillary column was regenerated by occasional elution with malonate buffer (pH 6.0) containing 0.5 M NaCl, to remove free conjugate. Free conjugate recovered in this manner could be reused up to eight times without significant decreases in the sensitivity of the immunoassay. This electrochemical flow immunoassay requires only minute quantities of serum and generates highly reproducible results.

Antigen-Antibody Complex↗

PubMed2001

Ulcerative colitis after autologous peripheral blood stem cell transplantation for non-Hodgkin's lymphoma.

A 54-year-old woman with peripheral T cell lymphoma in second complete remission (CR) received an autologous peripheral blood stem cell transplant (PBSCT). Antibiotic-resistant bloody diarrhea, and fever developed 110 days after transplant. Blood and stool cultures were negative. Skin rash was not observed. Barium enema and colonoscopy showed typical features of pancolonic-type ulcerative colitis (UC). Endoscopic biopsies confirmed the diagnosis of UC. Mesalazine and immunosuppressive therapy improved symptoms dramatically. We detected serum antibodies against synthetic tropomyosin (TM) peptide when UC was diagnosed. We postulate that autoimmunity including autoreactive anti-TM antibodies may be involved in the pathogenesis of UC after autologous PBSCT in this patient.

Autoantibodies↗

PubMed2001

In situ visualization of ultraviolet-light-induced DNA damage repair in locally irradiated human fibroblasts.

We have developed a novel method that uses a microfilter mask to produce ultraviolet-induced DNA lesions in localized areas of the cell nucleus. This technique allows us to visualize localized DNA repair in situ using immunologic probes. Two major types of DNA photoproducts [cyclobutane pyrimidine dimers and (6-4) photoproducts] were indeed detected in several foci per nucleus in normal human fibroblasts. They were repaired at those localized sites at different speeds, indicating that DNA photoproducts remain in relatively fixed nuclear positions during repair. A nucleotide excision repair protein, proliferating cell nuclear antigen, was recruited to the sites of DNA damage within 30 min after ultraviolet exposure. The level of proliferating cell nuclear antigen varied with DNA repair activity and diminished within 24 h. In contrast, almost no proliferating cell nuclear antigen fluorescence was observed within 3 h in xeroderma pigmentosum fibroblasts, which could not repair either type of photolesion. These results demonstrate that this technique is useful for visualizing the normal nucleotide excision repair process in vivo. Interestingly, however, in xeroderma pigmentosum cells, proliferating cell nuclear antigen appeared at ultraviolet damage sites after a delay and persisted as late as 72 h after ultraviolet exposure. This result suggests that this technique is also valuable for examining an incomplete or stalled nucleotide excision repair process caused by the lack of a single functional nucleotide excision repair protein. Thus, the technique provides a powerful approach to understanding the temporal and spatial interactions between DNA damage and damage-binding proteins in vivo.

Cell Line↗

PubMed2001

In search of the origin of the thymus: the thymus and GALT may be evolutionarily related.

The thymus is the major primary immune tissue for the production of functional T lymphocytes in vertebrates. However, its evolutionary origin is unknown. It has recently been shown that the generation of local T cells also occurs in gut-associated lymphoid tissues (GALT). This suggests that the thymus and GALT have similar functions and that they might be evolutionarily related. We discuss the possibility that the thymus may have evolved from mucosa-associated lymphoid tissues (MALT) located in the gill region in early vertebrates. Various facts supporting this proposal are summarized.

Animals↗

PubMed2001

The effects of therapeutic electric stimulation on acute muscle atrophy in rats after spinal cord injury.

OBJECTIVE: To evaluate the effects of electric stimulation in preventing acute muscle atrophy after spinal cord transection in rats. DESIGN: A randomized experimental design. SETTING: Animal facilities for experimental medicine. ANIMALS: Fifty-six adult male Wistar rats assigned to control, low-frequency, and high-frequency groups. INTERVENTIONS: The rats were implanted with a percutaneous intramuscular electrode in the vicinity of the peroneal nerve; then the spinal cord was transected in a T9 level. The stimulation frequency was low (20Hz) or high (100Hz). The stimulation cycle was 4 seconds of stimulation every 8 seconds. MAIN OUTCOME MEASUREMENTS: The lesser fiber diameters from type 1, 2A, and 2B muscle fibers were measured. In another assessment, maximal contraction force was measured. The muscle force produced at 20 and 100Hz was expressed as increasing values in tetanic force. RESULTS: Comparison between nonstimulated and stimulated tibialis anterior muscles found that atrophy of type 1 fibers (p < .01) and type 2B fibers (p < .05) at both stimulated levels and of type 2A fibers at 100-Hz level (p < .05) was prevented by therapeutic electric stimulation (TES). There were significant differences in the size of muscle fiber diameter between nonstimulated and stimulated muscles at 100Hz in type 2A and, markedly, in type 2B. The increasing value of muscle force was significantly greater at 100Hz than at 20Hz (p < .05). No significant histologic differences were observed between high- and low-frequency stimulated fibers of any of the 3 muscle types. CONCLUSIONS: Acute atrophy of muscle fibers was more effectively prevented by high-frequency stimulation (100Hz) than by no stimulation or low-frequency stimulation (20Hz). The increasing value of muscle force was significantly greater at high-frequency than low-frequency stimulation, suggesting that the clinical application of high-frequency stimulation in acute spinal cord injury should be studied.

Acute Disease↗

PubMed2001

Pulsed Doppler sonography for the diagnosis of strangulation in small bowel obstruction.

BACKGROUND/PURPOSE: This study was undertaken to assess the usefulness of pulsed Doppler sonography (PDS) for the detection of strangulation in small bowel obstruction by evaluating the hemodynamics in the superior mesenteric artery (SMA). METHODS: The authors performed PDS in 117 normal children: 22 children aged 0 to 1 months (group I), 27 children aged 1 to 12 months (group II), 36 children aged 1 to 6 years (group III), and 32 children aged 7 to 15 years (group IV). Patients included 25 with simple obstruction: 1 in group II, 10 in group III, and 14 in group IV; and 9 with strangulating obstruction: 2 in group I, 2 in group II, 3 in group III, and 2 in group IV. The authors measured the peak-systolic velocity, end-diastolic velocity (EDV), and mean average velocity and calculated the resistive index (RI). RESULTS: The authors observed both a significant decrease in the EDV and increase in the RI for the SMA in strangulating obstruction compared with simple obstruction. CONCLUSION: Analysis of the hemodynamics in the SMA using PDS is useful to differentiate strangulating obstruction from simple obstruction.

Adolescent↗

PubMed2001

Pulsed Doppler sonography of the hilar renal artery: differentiation of obstructive from nonobstructive hydronephrosis in children.

BACKGROUND/PURPOSE: It is difficult to detect the arcuate or cortical renal arteries when performing pulsed Doppler sonography (PDS) for congenital hydronephrosis. This study was undergone to assess the usefulness of PDS of the hilar renal artery to differentiate obstructive from nonobstructive hydronephrosis. METHODS: The authors performed PDS of the hilar renal artery in 80 normal children: 20 aged 0 to 1 months (group I), 20 aged 1 to 12 months (group II), 20 aged 1 to 6 years (group III), and 20 aged 7 to 15 years (group IV). Based on diuretic renography findings, 22 kidneys from 19 children with a ureteropelvic junction (UPJ) stricture were divided into 7 dilated obstructed and 15 dilated nonobstructed kidneys. The peak-systolic velocity (PSV), end-diastolic velocity (EDV), mean average velocity (Vm) and the resistive index (RI = [PSV - EDV]/PSV) were measured at the hilar renal artery. RESULTS: There was a significant difference in the RI of the hilar renal artery between obstructive and nonobstructive hydronephrosis. CONCLUSION: A pulsed Doppler evaluation of the hilar renal artery is useful for detecting an obstructive UPJ stricture compared with assessing arcuate or cortical renal arteries.

Adolescent↗

PubMed2001

Successful surgical treatment of two cases of congenital chylous ascites.

The authors report on 2 patients with congenital chylous ascites who underwent successful lymphatic duct ligation after a laparoscopic lymphoid dye test. Fetal ascites had been detected in both cases, and both babies were born with marked abdominal swelling. Given that conservative treatment by medium-chain triglyceride (MCT) milk and total parenteral nutrition (TPN) was ineffective, the authors elected to perform lymphatic duct ligation on the 95th postnatal day in the former case and on the 27th postnatal day in the latter case. Lipophilic dye was administered preoperatively both through oral and subcutaneous routes, and the peritoneal cavity was explored using laparoscopy. This laparoscopic lymphoid dye test precisely identified the area of chylous leakage, and the authors were able to repair the malformed lymphatic duct directly at laparotomy. Both postoperative courses have been favorable with no recurrence of symptoms. The lymphatic duct ligation should be considered in cases resistant to conservative treatment for over a month. The present laparoscopic lymphoid dye test is a novel and useful procedure that allows surgeons to identify the exact location of chylous leakage, and thus successfully ligate the lymphatic duct.

Chylous Ascites↗

PubMed2001

The ligands/activators for peroxisome proliferator-activated receptor alpha (PPARalpha) and PPARgamma increase Cu2+,Zn2+-superoxide dismutase and decrease p22phox message expressions in primary endothelial cells.

We examined the effects of a variety of ligands/activators of the peroxisome proliferator-activated receptor (PPAR) on the expression of the superoxide scavenger enzyme, Cu2+,Zn2+-superoxide dismutase (CuZn-SOD), and the superoxide generating enzyme nicotinamide adenine dinucleotide phosphate (reduced form) (NADPH) oxidase in primary cultures of human umbilical vein endothelial cells (HUVEC) and human aorta endothelial cells (HAEC). Our data show that 3 types of PPARs, PPARalpha, PPARbeta/delta/Nuc1, and PPARgamma are expressed in endothelial cells. Bezafibrate, which is a ligand/activator for PPARalpha, increased the CuZn-SOD gene expression and protein levels in endothelial cells. Troglitazone and pioglitazone, which are ligands/activators for PPARgamma, also induced PPARalpha gene and protein expression and increased CuZn-SOD gene expression and protein levels in addition to increasing PPARgamma gene and protein expression in endothelial cells. Moreover, with treatment of monounsaturated and polyunsaturated fatty acids (PUFA), the CuZn-SOD mRNA levels were positively correlated with PPARalpha mRNA levels (r = .872, P < .0001) in primary endothelial cells. In addition, the phorbol myristate acetate (PMA)-stimulated or PMA-nonstimulated 22-kd a-subunit (p22phox) mRNA levels and 47-kd a-subunit (p47phox) protein levels in NADPH oxidase were decreased by treatment with PPARalpha and PPARgamma ligands/activators. These results suggest that PPARalpha and PPARgamma gene and protein expression in endothelial cells may play a physiologic role as radical scavengers, although the details of these mechanisms remain to be established.

Cells, Cultured↗

PubMed2001

Adult rat otic placode-derived neurons and sensory epithelium express all four erbB receptors: a role in regulating vestibular ganglion neuron viability.

The erbB receptor family consists of erbB1/epidermal growth factor receptor, erbB2/neu, erbB3, and erbB4, all of which have been implicated in cell proliferation, differentiation, and survival in several tissues. In the nervous system, these family members can function in a trophic capacity for certain subpopulations of neurons and some types of non-neuronal cells. Vestibular sensory epithelial cells and vestibular ganglion neurons are derived from ectodermal otic placode and are essential components of the peripheral vestibular system, the sensory system for balance. Recent studies in mammals suggest that certain ligands of the epidermal growth factor receptor can induce proliferation of vestibular sensory epithelial cells. We now show that vestibular ganglion neurons and vestibular sensory epithelial cells express all four erbB receptors in adult rats. Cultured vestibular ganglion neurons also expressed all four erbB family members and were therefore used to analyze the effects of modulating erbB signaling on differentiated vestibular ganglion neurons. Transforming growth factor-alpha (a ligand for epidermal growth factor receptor) and sensory and motor neuron-derived factor (a ligand for erbB3 and erbB4) promoted vestibular ganglion neuron viability, whereas epidermal growth factor (another ligand for epidermal growth factor receptor) did not. Glial growth factor 2 (another ligand for erbB3 and erbB4) and an antibody that blocks erbB2/neu-mediated signaling inhibited vestibular ganglion neuron viability. Collectively, these observations indicate that erbB signaling regulates the viability of differentiated otic placode-derived cells in mammals and suggest that exogenous modulation of erbB signaling in peripheral vestibular tissues may prove therapeutically useful in peripheral vestibular disorders.

Animals↗

PubMed2001

Expression of pyrimidine 5'-nucleotidase subclass I during erythrocyte maturation in rats.

The subclass I enzyme of rat pyrimidine 5'-nucleotidase (P5N-I), which preferentially hydrolyzes (deoxy)CMP and UMP, is distributed specifically in red blood cells (RBCs), and its activity increases approximately six-fold as compared to the control value after erythropoietic induction by phenylhydrazine administration. In this study, we detected rat P5N-I protein by using antibodies against the chicken P5N-I enzyme. The molecular mass of rat P5N-I was approximately 37 kDa, as estimated by gel filtration chromatography and Western blot analysis. The pI value of the enzyme was approximately 5.7. This protein band was detected only in RBC lysate extract, i.e., not in cytosol from the erythropoietic spleen. Protein mass of the P5N-I enzyme, estimated by immunoblot analysis, was increased in proportion to the enzyme activity after erythropoietic induction in rats. No phosphorylation of the enzyme protein was detected by immunoblot analysis with anti-phosphoserine or anti-phosphotyrosine antibody. In conclusion, these findings indicate that the rat P5N-I enzyme is expressed specifically in reticulocytes and may therefore be essential in the maturation process of rat erythrocytes.

5'-Nucleotidase↗

PubMed2001

Effects of photoreactivation of cyclobutane pyrimidine dimers and pyrimidine (6-4) pyrimidone photoproducts on ultraviolet mutagenesis in SOS-induced repair-deficient Escherichia coli.

Using purified photolyases for pyrimidine (6-4) pyrimidone photoproducts [(6-4)PP] and cyclobutane pyrimidine dimers (CPD), the effects of photoreactivation on mutagenesis were examined in the supF gene on a plasmid transfected into repair-deficient SOS-induced Escherichia coli host cells. More than 95% of CPD and (6-4)PP were removed from plasmid DNA by treatment with CPD photolyase and (6-4)photolyase, respectively. In each photolyase treatment, base substitutions at dipyrimidine sequences were predominantly observed. Of the single base substitutions observed after CPD photoreactivation, 83% were A:T-->G:C transitions at 5'-TT-3' sites. After (6-4)photolyase treatment, 81% were G:C-->A:T transitions at 5'-CC-3' and 5'-TC-3' sequences. Thus, the major mutagenic photoproducts of single-base substitutions were CPD at 5'-CC-3' or 5'-TC-3' sites and (6-4)PP at 5'-TT-3' sites. Tandem double mutations occurred mainly at 5'-CC-3' sites and were CPD-photoreactivated, suggesting that CPD at 5'-CC-3' was responsible for tandem double mutations. After photoreactivation of both CPD and (6-4)PP, single-base substitutions were primarily G:C-->A:T transitions at 5'-CC-3' or 5'-TC-3' sites and A:T-->G:C transitions at 5'-TT-3' sites, and secondarily G:C-->T:A transversions at 5'-CC-3' sites, G:C-->C:G transversions at 5'-CC-3' sites and A:T-->T:A transversions at 5'-TT-3' sites, which were essentially the same as those observed after photoreactivation of CPD alone, (6-4)PP alone and without photoreactivation. Thus, these transversions were not derived from unknown UV adducts but from incompletely repaired CPD and (6-4)PP.

Base Sequence↗