Biomedical subjects

S Matsuda

Publications and source records attributed to S Matsuda.

At least 199 records · Page 11Linked to original sources

PubMed1998

Aneurysm of the major vessels in neurofibromatosis.

The case of a patient who presented with a ruptured aneurysm of the brachial artery and type I neurofibromatosis is presented. Angiography revealed a ruptured aneurysm of the brachial artery in the middle of the upper arm. Repair of the artery with autogenous vein grafting was impossible due to the extremely brittle brachial artery and accompanying veins. The blood supply distal to the aneurysm was secured by collaterals, and the aneurysm, including a relatively long portion of the brachial artery and veins adjacent to the aneurysm, was resected. The patient died of massive hemorrhage from the subclavian artery of the involved side 9 days postoperatively. Histological and immunohistological examinations of the tissues involved in the ruptured aneurysm were conducted. The resected brachial artery and veins were surrounded by hypertrophied tissue which tested positive for S-100 protein and negative for desmin and action. These findings suggest that the origin of the proliferating tissue was not mesodermal dysplasia, but neurofibroma occurring near or in the vessels. A ruptured aneurysm in a patient with neurofibromatosis should not be treated with reconstruction of the vessels. The treatment of choice is surgical or endovascular occlusion of the vessels involved.

Adult↗

PubMed1998

Reliability of the anteroposterior axis and the posterior condylar axis for determining rotational alignment of the femoral component in total knee arthroplasty.

We examined the reliability of the anteroposterior and posterior condylar axes for determining rotational alignment of the femoral component in total knee arthroplasty (TKA). A computed tomography scan was taken at the level of the femoral epicondyle in 84 knees (27 varus knees with medial femorotibial arthritis (FT-OA) in 26 patients, 17 knees with patellofemoral arthritis in 14 patients, and 40 normal knees in 40 volunteers). On the image, an anteroposterior axis, a line perpendicular to the anteroposterior axis, an epicondylar axis and a posterior condylar axis were drawn, and the relationship between the three axes was assessed. The mean values for the 84 knees were evaluated, and the posterior condylar axis was 6.0 degrees +/- 2.4 degrees internally rotated relative to the epicondylar axis, while the line perpendicular to the anteroposterior axis was 1.4 degrees +/- 3.3 degrees internally rotated relative to the epicondylar axis. The internal rotation angle of the posterior condylar axis relative to the epicondylar axis was 6.2 degrees +/- 1.9 degrees in the knees with medial femorotibial arthritis, 6.4 degrees +/- 2.4 degrees in the knees with patellofemoral arthritis, and 5.8 degrees +/- 2.7 degrees in the normal knees, showing consistent values in normal and osteoarthritic knees. The internal rotation angle of the line perpendicular to the anteroposterior axis relative to the epicondylar axis was 0.1 degrees +/- 3.3 degrees, 1.3 degrees +/- 3. 3 degrees, and 2.3 degrees +/- 3.1 degrees in the three groups, respectively (i.e., there were significant differences between the medial FT-OA knees and the normal knees). The results demonstrated that the anteroposterior axis was rotated externally to a significant degree in medial FT-OA knees and was less reliable than the posterior condylar axis for use in alignment for TKA on medial FT-OA knees.

Aged↗

PubMed1998

A novel surgical glue composed of gelatin and N-hydroxysuccinimide activated poly(L-glutamic acid): Part 1. Synthesis of activated poly(L-glutamic acid) and its gelation with gelatin.

Although fibrin glue has been widely used as a surgical adhesive, its components, fibrinogen and thrombin, obtained from human blood are not completely free from the risk of virus infection due to acquired immune deficiency and hepatitis. Recently, we have reported that a polymer pair composed of gelatin and poly(L-glutamic acid) (PLGA) promptly forms a gel and can firmly bond to soft tissues when crosslinked with the aid of water-soluble carbodiimide (WSC). The present study was undertaken to design a new PLGA-gelatin glue without using WSC. Two kinds of PLGA with molecular weights of 71 and 22 kDa were employed to prepare N-hydroxysuccinimide (NHS) activated derivatives. The NHS-activated PLGA could be synthesized at high yields and was found to be stable for an extended time without losing the ability to crosslink with gelatin when stored under a dry-cold condition. This NHS-activated PLGA could spontaneously form a gel with gelatin in an aqueous solution within a short time, comparable to a commercial fibrin glue, when gelation was allowed to proceed at pH 8.3. The NHS-activated PLGA prepared from PLGA with the molecular weight of 22 kDa could be readily dissolved at high concentrations and its ability to form a gel was maintained for more than 10 min when an acidic 8% NHS-activated PLGA solution was used. The bonding strength of PLGA gelatin glues with natural tissue was higher than that of fibrin glue. These findings strongly suggest that this combination of gelatin and NHS-PLGA is very promising as a surgical adhesive and may possibly replace fibrin glues prepared from human blood components.

Animals↗

PubMed1998

Arcuate keratotomy to treat corneal astigmatism after cataract surgery: a prospective evaluation of predictability and effectiveness.

OBJECTIVE: Although several nomograms are available for the incisional keratotomy to correct naturally occurring astigmatism, astigmatic keratotomy in eyes after cataract surgery has not been well analyzed. The predictability and effectiveness of arcuate keratotomy in pseudophakic eyes were studied. DESIGN: A prospective, multicenter study. PARTICIPANTS: One hundred four eyes of 86 patients with residual corneal astigmatism of 1.5 diopters (D) or more after cataract surgery were examined. INTERVENTION: Arcuate keratotomy was performed in nine centers by nine surgeons. MAIN OUTCOME MEASURES: The amount of astigmatic correction was calculated using the vector analysis of preoperative and 6-month postoperative refractive cylinder results. RESULTS: Multiple regression analysis showed that optical zone size, number of incisions, and incision length had significant correlations with the amount of astigmatic correction. The regression equation was expressed as effects = (-0.643 x optical zone size) + (0.998 x incision number) + (0.057 x incision length) + 2.356. The parameter of predictability (r2: 35%) was lower than that reported for congenital astigmatism (48 to approximately 56%). A new nomogram was derived based on the multiple regression equation. CONCLUSIONS: Astigmatic keratotomy in pseudophakic eyes is less predictable than that in eyes with idiopathic astigmatism, but the procedure is sufficiently effective in reducing the residual astigmatism after cataract surgery. Individual nomograms are necessary for astigmatic keratotomy in eyes with naturally occurring and postsurgical astigmatism.

Aged↗

PubMed1998

Contact stress analysis in meniscal bearing total knee arthroplasty.

The effect of a mobile meniscal bearing on tibiofemoral contact stress was tested with a standard fixed tibial component and with movable tibial components (anteroposterior sliding, rotationally sliding, and anteroposterior and rotationally sliding). A digital electronic sensor was used to detect tibiofemoral contact location in five cadaver knees, then the location was reproduced while peak and mean stresses were measured under compressive load at 0 degrees, 30 degrees, 60 degrees, and 90 degrees of flexion. Stresses were measured when the tibial component was normally aligned and at 15 degrees internal and 15 degrees external rotation. To evaluate the effect of excessive overhang of the polyethylene articular surface, undersurface stress of the rotationally sliding component was also measured with a 30 degrees and a 45 degrees malrotated tibial tray. Uppersurface stresses of the fixed-bearing components were significantly higher at full extension than those recorded in components with rotational mobility. Undersurface stresses were always lower than uppersurface stresses, but correlated with uppersurface stresses. Undersurface stresses of the rotationally sliding component gradually increased as the malrotation angle of the tray increased. A mobile meniscal bearing surface appears to offer an advantage over a standard fixed component when rotational malalignment of the tibial component occurs. However, with severe rotational malalignment, edge contact markedly increases undersurface stresses, which could cause deformity and subluxation.

Adult↗

PubMed1998

Effect of patellar meniscus on patellofemoral contact stress in total knee arthroplasty.

The effect of a meniscus of fibrous tissue (patellar meniscus), on patellofemoral contact area and stresses was evaluated. Two knees with total knee arthroplasty and dome-shaped patellar components were retrieved at autopsy. Both had substantial fibrous menisci surrounding the dome of the patellar component. Contact area and contact stresses were measured with a digital electronic sensor, first with the patellar meniscus intact, then again after the patellar meniscus was removed. No dramatic difference was detected in patellofemoral contact area and contact stresses between the patellas with an intact or removed patellar meniscus, and there was no detectable load under the patellar meniscus. The results of this case study suggest that fibrous tissue surrounding the dome-shaped patellar component does not share compressive loads with the patellar component.

Aged↗

PubMed1998

An ecologic study of the relationship between mean birth weight, temperature and calorie consumption level in Japan.

This study reports an ecologic analysis of the relationship between mean birth weight (MBW) and nutritional, medical, and social variables, using 1982 data for 47 prefectures in Japan. Correlation analysis showed that variables that correlated significantly with MBW were mean temperature (r = 0.63), total calorie intake (r = 0.56), and body mass index of women (r = 0.60). It is concluded that the MBW level in a given community represents the long and short term nutritional condition of mothers, and that the level may follow Bergman's law: 'In the same species, the body size of an animal increases along with latitude; that is, the lower the temperature, the larger the body size.'

Birth Weight↗

PubMed1998

ANA, a novel member of Tob/BTG1 family, is expressed in the ventricular zone of the developing central nervous system.

Using a polymerase chain reaction-mediated cloning procedure, we have identified a novel member, termed ANA (from Abundant in Neuroepithelium Area), of Tob/BTG1 family of antiproliferative genes. Molecular cloning and analysis of cDNAs revealed that the human and mouse ANA encoded a protein of 252 amino acids. The amino-terminal half of ANA was homologous to the previously characterized antiproliferative gene products, BTG1, PC3/TIS21/BTG2, and Tob. The human ANA gene was localized at chromosome 21q11.2-q21.1. ANA was expressed in a variety of tissues and cell lines, its expression being high in the ovary, testis, prostate, thymus, and lung. Further analysis revealed that ANA expression was high in the ventricular zone of the developing central nervous system. Finally, overexpression of ANA impaired serum-induced cell cycle progression from the G0/G1 to S phase. In conclusion, ANA is a fourth member of the Tob/BTG1 family that might play roles in neurogenesis in the central nervous system.

Amino Acid Sequence↗

PubMed1998

GC/MS analysis of urinary excretion of 9alpha,11beta-PGF2 in acute and exercise-induced asthma in children.

BACKGROUND: 9Alpha,11beta-prostaglandin (PG) F2 is an initial metabolite of PGD2 which has a potent bronchoconstrictive activity. OBJECTIVES: We measured the urinary levels of 9alpha,11beta-PGF2 in asthmatic children to investigate its role in not only acute asthmatic attack in a time course study but also in exercise-induced asthma (EIA). METHODS: In the acute asthma study, 30 asthmatic children were examined. Urine samples were collected on the first, third, and sixth days. Urinary levels of 9alpha,11beta-PGF2 were measured with gas chromatography mass spectrometry using the electron impact method. In the exercise challenge study, 14 children with EIA and 14 children without EIA were studied. Urine samples were collected before exercise challenge, and at 1 h, and 5 h after exercise challenge. Urinary levels of 9alpha,11beta-PGF2 were measured. RESULTS: Elevated urinary levels of 9alpha,11beta-PGF2, which were observed on the first day when treatment was started in the hospital, were gradually decreased on the third day (P < 0.05), and on the sixth day (P < 0.01). A significant correlation between urinary levels of 9alpha,11beta-PGF2 and symptom scores (P < 0.005) was observed on the first day. In EIA, there was a significant increase in urinary levels of 9alpha,11beta-PGF2 at 1 h (P < 0.01) and at 5 h (P < 0.01) after exercise challenge, but not in the children without EIA. CONCLUSION: 9Alpha,11beta-PGF2 may be involved in the pathogenesis of acute and exercise-induced asthma in children.

Acute Disease↗

PubMed1998

Rad52 forms ring structures and co-operates with RPA in single-strand DNA annealing.

BACKGROUND: The RAD52 epistasis group in Saccharomyces cerevisiae is involved in various types of homologous recombination including recombinational double-strand break (DSB) repair and meiotic recombination. A RecA homologue, Rad51, plays a pivotal role in homology search and strand exchange. Genetic analysis has shown that among members of its epistasis group, RAD52 alone is required for recombination between direct repeats yielding deletions. Very little has been discovered about the biochemical roles and structure of the Rad52 protein. RESULTS: Purified Rad52 protein binds to both single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA). Electron microscope observations revealed that Rad52 molecules form multimeric rings. An increase in the intensity of fluorescence when Rad52 is bound to epsilonDNA showed an alteration of the structure of ssDNA. RPA was binding to Rad52 and enhanced the annealing of complementary ssDNA molecules. This enhancement was not observed in Escherichia coli SSB protein or T4 phage gp32 protein. CONCLUSION: Rad52 forms a ring-like structure and binds to ssDNA. Its structure and DNA binding properties are different from those of Rad51. The interaction of Rad52 with RPA plays an important role in the enhancement of annealing of complementary ssDNAs. We therefore propose that Rad52 mediates the RAD51-independent recombination through an ssDNA annealing, assisted by RPA.

DNA Replication↗

PubMed1998

CD4- and TCRalphabeta-positive T lymphocytes predominantly infiltrated into well-moderately differentiated colon adenocarcinoma tissues.

Intraepithelial T lymphocytes have been reported as being functional in the growth of epithelial cells and also in the discrimination of aberrant cells, whereas their function against colon adenocarcinoma cells is obscure. The phenotype of colon intraepithelial T lymphocytes has been found in patients with inflammatory bowel diseases but not in patients with colon adenocarcinoma. In this study, we investigated cell surface markers of tumor-infiltrating T lymphocytes of adenocarcinoma of the colon and rectum at various grades of differentiation and intraepithelial T lymphocytes of adjacent normal colon by enzyme immunostaining. Among intraepithelial T lymphocytes of the normal colon, CD8-and TCRgammadelta-positive T lymphocytes were predominant as described. In contrast, tumor-infiltrating T lymphocytes of well-moderately differentiated adenocarcinoma of the colon and rectum were predominantly CD4- and TCRalphabeta-positive. The decrease of TCRgammadelta-positive T lymphocytes and the increase of CD4 and TCRalphabeta-positive T lymphocytes in adenocarcinoma tissues of the colon and rectum suggests that an alteration of the local immune system participates in the formation of adenoma and/or adenocarcinoma of the colon and rectum, resulting in infiltration of CD4-positive T lymphocytes that have certain activity against transformed cells.

Adenocarcinoma↗

PubMed1998

Femoral condyle geometry in the normal and varus knee.

Femoral condyle geometry was evaluated in 30 normal and 30 varus knees using magnetic resonance imaging. In the sagittal view, the distal part of the medial condyle was deformed in the varus knees, but there was no significant difference in the posterior part of the medial condyle between the normal and varus knees. In the transverse view, the transepicondylar axis (a reliable rotational landmark) showed approximately 6 degrees external rotation relative to the posterior condylar axis in the varus knees and the normal knees. The results of this study suggest that no hypoplasia exists at the posterior part of the medial condyle in varus knees. In addition, the posterior condylar axis may be a reliable rotational landmark but is in relative internal rotation in varus knees when total knee arthroplasty is performed.

Aged↗

PubMed1998

Epidermal growth factor protects neuronal cells in vivo and in vitro against transient forebrain ischemia- and free radical-induced injuries.

Epidermal growth factor (EGF) has been considered to be a candidate for neurotrophic factors on the basis of the results of several in vitro studies. However, the in vivo effect of EGF on ischemic neurons as well as its mechanism of action have not been fully understood. In the present in vivo study using a gerbil ischemia-model, we examined the effects of EGF on ischemia-induced learning disability and hippocampal CA1 neuron damage. Cerebroventricular infusion of EGF (24 or 120 ng/d) for 7 days to gerbils starting 2 hours before or immediately after transient forebrain ischemia caused a significant prolongation of response latency time in a passive avoidance task in comparison with the response latency of vehicle-treated ischemic animals. Subsequent histologic examinations showed that EGF effectively prevented delayed neuronal death of CA1 neurons in the stratum pyramidale and preserved synapses intact within the strata moleculare, radiatum, and oriens of the hippocampal CA1 region. In situ detection of DNA fragmentation (TUNEL staining) revealed that ischemic animals infused with EGF contained fewer TUNEL-positive neurons in the hippocampal CA1 field than those infused with vehicle alone at the seventh day after ischemia. In primary hippocampal cultures, EGF (0.048 to 6.0 ng/mL) extended the survival of cultured neurons, facilitated neurite outgrowth, and prevented neuronal damage caused by the hydroxyl radical-producing agent FeSO4 and by the peroxynitrite-producing agent 3-morpholinosydnonimine in a dose-dependent manner. Moreover, EGF significantly attenuated FeSO4-induced lipid peroxidation of cultured neurons. These findings suggest that EGF has a neuroprotective effect on ischemic hippocampal neurons in vivo possibly through inhibition of free radical neurotoxicity and lipid peroxidation.

Animals↗

PubMed1998

Changes in protein synthesis and calcium homeostasis in the thalamus of spontaneously hypertensive rats with focal cerebral ischemia.

The thalamus has been shown to undergo secondary degeneration after cerebrocortical ischemia. However, little is known about the time course of the retrograde thalamic degeneration. The present study was designed to investigate time-dependent changes in the morphology, protein synthesis and calcium metabolism of thalamic neurons in middle cerebral artery (MCA)-occluded spontaneously hypertensive stroke-prone rats that showed primary focal ischemia in the temporoparietal cortex after permanent occlusion of the left distal MCA. In the histologic study by light and electron microscopy, swelling of the nucleus and shrinkage of the perikarya were seen in some neurons of the ventroposterior (VP) thalamic nucleus on the lesioned side at 5 days after ischemia. At the same time, the incorporation of radiolabeled leucine in VP thalamic neurons began to decrease significantly with concomitant a decrease in the number of polyribosomes in the neurons. Conspicuous 45Ca accumulation was noted at 3 days after ischemia and persisted up to 1 month in the VP thalamic nucleus on the lesioned side. These findings suggest that the secondary thalamic degeneration after cortical infarction starts with disruption of calcium homeostasis in situ at the third day after MCA occlusion, followed by a decrease in polyribosomes but not by disaggregation of polyribosomes as seen in hippocampal CA1 neurons subjected to transient forebrain ischemia.

Animals↗

PubMed1998

Detection of HIV-Gag p24-specific antibodies in sera and saliva of HIV-1-infected adults and in sera of infants born to HIV-1-infected mothers.

Secretory immunoglobulin A (IgA) is known to play an important role in the mucosal defense against a variety of pathogens. Although the role of IgA antibodies during sexual transmission of HIV is not clear, HIV-specific IgA antibodies have been detected in various mucosal secretions of HIV-infected individuals. Using a monoclonal antibody against human IgA, we established an ELISA system to detect anti-HIV p24 IgA antibodies in sera and saliva. We have analyzed the levels of anti-HIV p24 IgG and IgA antibodies in sera and saliva of 107 and 119 adults, respectively, with HIV infection at different clinical stages, and in the sera of 13 infants born to HIV-infected mothers. The level of anti-HIV p24 IgA antibodies was lower in sera and higher in saliva as compared to that of anti-HIV p24 IgG antibodies. Where the percentage of HIV-specific serum antibody-positive cases decreased with disease progression, that of saliva antibody-positive cases increased in AIDS patients. Among the 13 infants born to HIV-infected mothers, 7 infants were HIV-p24-specific serum IgA positive. These sera were negative for anti-HIV p24 secretory IgA, suggesting that some infants develop their own immune responses against HIV infection. Thus, the detection of HIV-specific IgA antibodies, especially in saliva, could be a simple and reliable test for the diagnosis of HIV infection.

AIDS Serodiagnosis↗

PubMed1998

Central bisegmentectomy of the liver plus caudate lobectomy for carcinoma of the gallbladder.

Central bisegmentectomy of the liver is recommended as a radical surgical procedure for patients with liver-bed gallbladder carcinoma, which tends to directly invade the hepatic parenchyma through the liver bed. In this article, we describe the indications and our surgical techniques for central bisegmentectomy of the liver plus caudate lobectomy for carcinoma of the gallbladder. We employ combined resection of the caudate lobe, because the caudate lobe often becomes involved even in patients with liver-bed carcinoma. Resection of the extrahepatic bile duct is also required to achieve complete lymphadenectomy within the hepatoduodenal ligament, because tumor invasion of the hepatoduodenal ligament is frequently found. Extensive lymphadenectomy around the head of the pancreas together with removal of the para-aortic lymph nodes should be performed in patients with extensive lymph node metastases.

Gallbladder Neoplasms↗

PubMed1998

Analysis of prognostic factors in newly diagnosed acute promyelocytic leukemia treated with all-trans retinoic acid and chemotherapy. Japan Adult Leukemia Study Group.

PURPOSE: We conducted a multicenter study of differentiation therapy with all-trans retinoic acid (ATRA) followed by intensive chemotherapy in patients with newly diagnosed acute promyelocytic leukemia (APL) and analyzed the prognostic factors for predicting complete remission (CR), event-free survival (EFS), and disease-free survival (DFS). PATIENTS AND METHODS: All patients received ATRA until CR. If patients had an initial leukocyte count greater than 3.0 x 10(9)/L, they received daunorubicin (DNR) and behenoyl cytarabine (BHAC). During therapy, if patients showed blast and promyelocyte counts greater than 1.0 x 10(9)/L, they received additional DNR and BHAC. After achieving CR, patients received three courses of consolidation and six courses of maintenance/intensification chemotherapy. RESULTS: Of 198 registered, 196 were assessable (age range, 15 to 86 years; median, 46) and 173 (88%) achieved CR. Multivariate analysis showed that no or minor purpura at diagnosis (P = .0046) and age less than 30 years (P = .0076) were favorable factors for achievement of CR. Predicted 4-year overall survival and EFS rates were 74% and 54%, respectively, and the 4-year predicted DFS rate for 173 CR patients was 62%. Multivariate analysis showed that age less than 30 years (P = .0003) and initial leukocyte count less than 10 x 10(9)/L (P = .0296) were prognostic factors for longer EFS, and initial leukocyte count less than 10.0 x 10(9)/L was a sole significant prognostic factor for longer DFS (P = .0001). CONCLUSION: Our results show that age, hemorrhagic diathesis, and initial leukocyte count are prognostic factors for APL treated with ATRA followed by intensive chemotherapy.

Adolescent↗

PubMed1998

Eosinophilic myocarditis associated with toxicodermia caused by phenobarbital.

We report on a 37-year-old man with congestive heart failure caused by eosinophilic myocarditis associated with toxicodermia. He developed many annular skin eruptions and peripheral eosinophilia due to reactions against phenobarbital. Right ventricular endomyocardial biopsy revealed extensive infiltration of eosinophils in the myocardium. A drug lymphocyte-stimulating test (DLST) for phenobarbital was positive. His symptoms, cardiomegaly, and cardiac function were improved by discontinuing phenobarbital followed by oral administration of prednisolone. We conclude that this eosinophilic myocarditis must have been induced by an allergic reaction to phenobarbital and that long-term eosinophilia contributed to the myocardial injury.

Adult↗