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Biomedical subjects

T Maeda

Publications and source records attributed to T Maeda.

At least 721 records · Page 40Linked to original sources
PubMed1994

Cloning and sequence analysis of a plasmid-encoded 2-haloacid dehalogenase gene from Pseudomonas putida No. 109.

The 2-haloacid dehalogenase of Pseudomonas putida No. 109 was mediated by a 74-kb conjugative plasmid, which was transferred by mating into Pseudomonas and Escherichia coli and there expressed the dehalogenase. A 2.8-kb EcoRI-fragment generated from the plasmid was cloned and sequenced. The dehalogenase gene (dehH109) was identified by comparison with the N-terminal amino acid sequence and the molecular weight of the enzyme protein. The gene dehH109 coded for a 224-amino acid protein of M(r) 25,231, which showed significant homology to the other four L-specific 2-haloacid dehalogenases from Pseudomonas sp. CBS3, P. putida AJ1, and Xanthobacter autotrophicus GJ10 and also to the haloacetate dehalogenase H-2 from Moraxella sp. strain B, but no homology with another haloacetate dehalogenase H-1 and the D-specific 2-haloacid dehalogenase from P. putida AJ1.

Amino Acid Sequence↗
PubMed1994

Failure to detect brown adipose tissue uncoupling protein mRNA in benign symmetric lipomatosis (Madelung's disease).

We report a case of benign symmetric lipomatosis with hypothyroidism. Functional abnormalities and distribution of lipomas in benign symmetric lipomatosis suggest that the lipomas in this disorder may represent brown adipose tissue. In conditions where mRNAs of uncoupling protein, which is believed to be unique for brown adipose tissue mitochondria, were detected in one microgram of poly (A+) rat brown fat RNA, no signal at all was found in the lipomatous tissue, suggesting that the masses of benign symmetric lipomatosis are not functional brown adipose tissue.

Adipose Tissue, Brown↗
PubMed1994

Adrenergic innervation of the urinary bladder body in the cat with special reference to structure of the detrusor muscle: an immunohistochemical study of noradrenaline and its synthesizing enzymes.

The distribution of adrenergic nerves in the body detrusor muscle of the cat urinary bladder was studied by means of the immunohistochemical identification of noradrenaline (NA) and the NA synthesizing enzymes tyrosine hydroxylase, aromatic L-aminoacid decarboxylase and dopamine beta-hydroxylase. We identified the basic structural organization of the detrusor muscle, which had previously been described as lacking discernible layers. In the lateral wall, both outer longitudinal and inner circular muscle bundles were present, the latter extending in both anterior and posterior directions. The posteriorly running bundles came to lie on the outside of the posterior wall where they enabled recognition of inner longitudinal muscle bundles. Those running anteriorly were dispersed to enter the longitudinal bundles in the anterior wall. NA-immunoreactive nerve fibers in the detrusor muscle of the bladder were found to be similar to those immunoreactive for NA synthesizing enzymes in both distribution and density. In the upper and middle bladder body--including the dome (apex)--immunoreactive nerve fibers were always more abundant in the outer part of the detrusor muscle than in the inner part, regardless of the course of muscle bundles. Even in individual muscle bundles running from the inside to the outer surface, the outer part was more richly innervated by immunoreactive fibers than the inner part. In the bladder dome, a moderate number of immunoreactive nerve fibers preferentially innervated the outer part of the muscle layer. In the lower bladder body, these nerve fibers increased in density in the inner part of the detrusor muscle. There was no sexual difference in density or distribution of nerve fibers. NA- and NA synthesizing enzyme-immunoreactive nerve fibers were markedly decreased in number after 6-hydroxydopamine treatment. No dopamine- or phenylethanolamine-N-methyltransferase-immunoreactive nerve fibers were present in the bladder. The findings of this study indicate that the cat bladder musculature includes longitudinal and circular muscle bundles, both of which are extensively innervated by adrenergic nerves, particularly in the outer part of the bladder.

Adrenergic Fibers↗
PubMed1994

The relationship between odontoblasts and immunocompetent cells during dentinogenesis in rat incisors: an immunohistochemical study using OX6-monoclonal antibody.

The relationship between odontoblasts and class II major histocompatibility complex (MHC) antigen-expressing cells in the process of dentinogenesis was studied in rat lower incisors, employing immunohistochemistry using OX6-monoclonal antibody. The dental pulp contained numerous OX6-immunopositive cells that varied in morphology from dendritic to spindle under physiological conditions. Under the electron microscope, these immunopositive cells shared common cytoplasmic features, i.e., multivesicular bodies and characteristic fine tubulovesicular structures in their cytoplasm. At the early stage of dentinogenesis, OX6-immunopositive cells, presumably of the immature type, were located in the subodontoblastic layer. During active dentin formation, the OX6-immunopositive cells increased in number and appeared in the odontoblast layer, associating intimately with fenestrated capillaries situated close to the predentin. These cells showed a dendritic appearance and possessed various sizes of multivesicular bodies and characteristic fine tubulovesicular structures, but never contained typical phagosomes. On the other hand, immunopositive macrophages characterized by typical phagosomes tended to occupy the central portion of the pulp. The results suggest that most, if not all, OX6-immunopositive cells situated deep in the odontoblast layer are dendritic cells playing a role in the defense system of the dental pulp against antigenic molecules arriving from the circulation via the fenestrated capillaries. The increasing number of OX6-immunopositive or immunonegative macrophages appearing near the incisal end of the tooth is thought to be involved in the elimination of degenerated odontoblasts.

Animals↗
PubMed1994

Unusual combination of insulin-dependent diabetes mellitus with transient-pituitary-isolated gonadotropin deficiency.

We report a 27-year-old man with insulin-dependent diabetes mellitus and transient-pituitary-isolated gonadotropin deficiency. He had typical diabetic symptoms, and loss of libido of a 6-month duration. Although antibodies to islet cells or islet cell surface were not detected in his sera, daily urinary excretion of c-peptide immunoreactivity was extremely low, and antibodies to the pituitary AtT-20 cell were detected. The plasma responses of gonadotropin to a single and a repetitive luteinizing hormone-releasing hormone were extremely low, whereas testosterone concentrations in the serum and urine were low normal. After 6 months, the gonadotropin deficiency and loss of libido were not detected and antibodies to the AtT-20 cell was negative. We suspected that both insulin-dependent diabetes mellitus and transient-gonadotropin-deficiency might be an autoimmune mechanism.

Adult↗
PubMed1994

Diagnosis of inflammatory pseudotumor of the liver: value of CT.

OBJECTIVE: Inflammatory pseudotumor of the liver is a localized mass consisting of a fibrous stroma and chronic inflammatory infiltrate without anaplasia. Diagnosis of this rare disease is important to avoid surgery. The purpose of this study was to determine if CT is useful in the diagnosis of this lesion. SUBJECTS AND METHODS: CT scans of nine patients with a proved diagnosis of inflammatory pseudotumor of the liver were reviewed. Diagnosis was made by the surgical resection in three patients and by percutaneous biopsy in six patients. Six patients had symptoms and laboratory data suggesting active inflammation caused by the pseudotumor. The remaining three patients were asymptomatic. CT scans were performed with IV administration of the contrast material; scans were obtained in the portal venous and delayed phases in six patients and in the delayed phase in three patients. CT scans were analyzed for the number and size of the hepatic masses, and the degree and pattern of contrast enhancement on portal venous phase and delayed-phase images. RESULTS: Eight patients had a solitary hepatic mass, and one patient had two masses on the CT scan. The average size of the masses in the symptomatic patients (8.3 cm) was larger than that in the asymptomatic group (3.6 cm). CT scans in the portal venous phase showed a variable degree of contrast enhancement (seven masses). At least a part of seven masses, six of which were in symptomatic patients, showed greater contrast enhancement on delayed-phase CT scans than on the normal liver parenchyma. No constant pattern of enhancement was observed on delayed-phase CT scans in asymptomatic patients. CONCLUSION: Inflammatory pseudotumor of the liver should be included in a differential diagnosis in patients with a hepatic mass on a CT scan, especially when patients are symptomatic and the mass is fairly large and solitary showing contrast enhancement greater than that of liver parenchyma on delayed-phase CT scans. Percutaneous biopsy should be performed to obtain a histologic confirmation.

Adolescent↗
PubMed1994

Study of hereditary trends in the shape of the murine mandible.

Inbred mice are a suitable material for genetic studies, and mandibular shape in particular provides a highly quantitative hereditary trait. We investigated which genetic trait in F1, F2 and N2 hybrid mice was most strongly affected by the presence of a large or small mandible in the parents. Ten C57BL/6By strain mice as parents with a small mandible and 10 MRL/n strain mice as parents with a large mandible were employed. Twenty-five (C57BL/6By male X MRL/n female) F1 and 67 F2 hybrids, and 28 (F1 male X C57BL/6By female) N2 backcross hybrids were obtained by laboratory mating. The inter-landmarks of the right mandible were measured by an electronic digitizer. Each mean value of horizontal dimensions in F1 mice resembled that in MRL/l mice, and that in N2 mice was intermediate between C57BL/6By and MRL/n mice. On the other hand, the mean values of vertical dimensions in F1, F2 and N2 hybrids were intermediate between those of C57BL/6By and MRL/n mice. Hence we suggest that horizontal dimensions are predominantly inherited by mice with a large mandible, and that vertical dimensions show intermediate inheritance between mice with large and small mandibles in the C57BL/6By and MRL/n strains.

Animals↗
PubMed1994

Surgical management of cavernous malformations of the third ventricle.

In order to determine adequate therapeutic approaches for cavernous malformations of the third ventricle, the authors reviewed a series of five such malformations managed at their institution and nine others reported in the literature. Four subgroups were identified in terms of the site of origin and could be characterized by different clinical manifestations: visual field defects and endocrine function deficits in patients with malformations in the suprachiasmatic region (six cases); symptoms caused by hydrocephalus in those with malformations in the foramen of Monro region (five cases); and deficits of short-term memory in those with malformations in the lateral wall (two cases) or of the floor of the third ventricle (one case). Unlike cavernous malformations at other locations, malformations of the third ventricle frequently demonstrated rapid growth (43%) and mass effects (71%). The surgical or autopsy findings suggested that the growth was attributable to repeated intralesional hemorrhages. Extralesional hemorrhage was also not uncommon, occurring in 29% of patients. Such tendencies require the adoption of a more aggressive approach to this particular group of cavernous malformations as compared to those in other locations. The risks of regrowth and extralesional hemorrhage appear to be reduced only by complete excision. The surgical approaches adopted should be aimed at providing the best access to the site where the malformation has arisen. The translamina terminalis approach for cavernous malformations in the suprachiasmatic region, the transventricular or transcallosal interfornicial approaches for those in the foramen of Monro region and the transvelum interpositum approach for those in the lateral wall or the floor of the third ventricle appear to be appropriate. In order to select the adequate surgical approach, precise diagnosis of the site of origin is crucial. In addition to neuroimaging techniques, the patient's initial symptoms provide valuable information.

Adult↗
PubMed1994

Concurrent development of hemiplegia and angina pectoris in a 46-year-old man with familial hypercholesterolemia and elevated serum Lp(a) concentrations.

We report a 46-year-old man with familial hypercholesterolemia who simultaneously developed angina pectoris and left hemiplegia. Angiography revealed complete tapering occlusion of the right internal carotid artery and a 75% stenosis of the right coronary artery. In addition to hypercholesterolemia, his serum Lp(a) levels were very high, with a mean (+/- SE) of 62 +/- 2 mg/dl.

Angina Pectoris↗
PubMed1994

Serum alpha-L-fucosidase activity and tumor size in hepatocellular carcinoma.

The serum level of alpha-L-fucosidase activity has been suggested as a useful marker in the diagnosis of hepatocellular carcinoma, although the precise mechanism behind the elevation of this parameter has not been determined. We found that the serum alpha-L-fucosidase activity level was significantly higher in 67 patients with hepatocellular carcinoma (695.1 +/- 245.5 nmol/ml/hr) than in 47 patients with cirrhosis (389.1 +/- 188.2 nmol/ml/hr; p < 0.001) and in 54 controls (202.0 +/- 104.6 nmol/ml/hr; p < 0.001). However, alpha-L-fucosidase activity was not correlated with tumor size (r = 0.134), whereas the alpha-fetoprotein level was correlated with tumor size (r = 0.580, p < 0.001). When 515.8 nmol/ml/hr was taken as the cutoff value (mean value in the controls plus 3 standard deviations), alpha-L-fucosidase activity was above the cutoff value in 12 of the 17 patients with a hepatocellular carcinoma less than 2 cm in diameter, in 28 of the 37 patients with a hepatocellular carcinoma less than 3 cm in diameter and in 52 of the 67 patients with hepatocellular carcinoma. In contrast, only 10 of the 47 patients with cirrhosis had levels above the cutoff value. These findings suggest that an increase in serum alpha-L-fucosidase activity in patients with cirrhosis may be a marker for detecting a hepatocellular carcinoma, especially a small tumor, because alpha-fetoprotein and des-gamma-carboxy-prothrombin are less promising as tumor markers.

Biomarkers↗
PubMed1994

[The rescue effect of FK506 in refractory rejection after cardiac transplantation].

The patient with dilated cardiomyopathy (NYHA class 4) under went cardiac transplantation at University of California, Los Angeles. Severe cardiac rejection was revealed one month after the transplantation. Steroid therapy was not effective, the rejection was resolved with OKT3 therapy and Anti-thymocyte globulin. Moreover, severe rejection was seen five months later. Steroid therapy was not effective. Cyclosporine administration was substituted for FK506 (0.02 mg/kg/day). After the induction of FK506, the number of CD8 positive cells decreased and cardiac rejection was successfully resolved. As side effect of FK506, bradycardia with heart rate of 50/min for 4 minutes appeared. However, it was well-controlled when the trough level of FK506 was reduced to less than 8 ng/ml.

Adult↗
PubMed1994

T cell receptor V alpha repertoire of infiltrating T cells in labial salivary glands from patients with Sjögren's syndrome.

OBJECTIVE: To analyze the T cell receptor (TCR) V alpha repertoire of infiltrating T cells in labial salivary glands of patients with Sjögren's syndrome (SS). METHODS: TCR V alpha genes of infiltrating T cells in lips from 2 patients with SS were examined, using the double step inverse polymerase chain reaction. Four and 7 clones encoding the VJC alpha region were established and sequenced, respectively. RESULTS: All 4 clones used the V alpha 17.1 gene in one patient, while 3 (42.8%) of 7 clones from the other patient used the V alpha 2 family gene (V alpha 2.1, V alpha 2.2, V alpha 2.4), and the other 3 clones used the V alpha 11.1 family gene. A comparison using labial salivary glands and peripheral blood showed that the predominant expression of V alpha 2, V alpha 11.1, and V alpha 17.1 gene segments is specific in the salivary glands. CONCLUSION: The TCR V alpha repertoire of infiltrating T cells from the lips of 2 patients with SS was relatively restricted in individual patients, thereby suggesting the limited heterogeneity of these cells in salivary glands.

Amino Acid Sequence↗
PubMed1994

Inhibition of skin xenograft rejection by depleting T-cell receptor alpha beta-bearing cells without T-cell receptor gamma delta-bearing cells or natural killer cells by monoclonal antibody.

We compared the effects of in vivo administration of the anti-T-cell receptor (TCR) alpha beta monoclonal antibody (mAb) (H57-597) to those of the anti-CD3 mAb (145-2C11), with or without anti-NK1.1 mAb (PK136), on xenogeneic skin graft survival in mice. In anti-TCR alpha beta mAb-treated B6 mice, F344 rat skin grafts survived for about 54 days, whereas in anti-CD3 mAb-treated B6 mice with or without anti-NK1.1 mAb treatment grafts survived about 25 days. In anti-TCR alpha beta mAb-treated B6 mice, TCR alpha beta-bearing T-lymphocyte function was completely abrogated, although TCR gamma delta-bearing T-lymphocyte function was still intact on day 9. In the anti-CD3 mAb-treated mice, the functions of both types of T lymphocytes were completely abrogated. On day 32, when most of the skin xenografts had been rejected in the anti-CD3 mAb-treated mice, the functions of both T lymphocytes had recovered considerably, and could actually respond to F344 antigens. In contrast, the function of TCR alpha beta-bearing cells had only partially recovered in the anti-TCR alpha beta mAb-treated mice. Finally, natural killer (NK) activity in the anti-TCR alpha beta mAb-treated mice was intact on day 32, when rat skin grafts still survived. In contrast, NK activity in the anti-CD3 mAb plus anti-NK1.1 mAb-treated mice did not recover on day 32, when skin xenografts had already been rejected. These results suggest that TCR gamma delta-bearing T cells and NK cells by themselves, at least in the absence of TCR alpha beta-bearing T cells, do not mediate xenogeneic skin graft rejection in mouse/rat combinations.

Animals↗
PubMed1994

[Experimental techniques for developing new drugs acting on dementia (3)--Experimental methods on the long-term potentiation].

Long-term potentiation (LTP) in the hippocampus is a long-lasting enhancement of excitatory synaptic transmission that follows brief tetanic stimulation of afferent fibers, and a candidate of neuronal substrata of learning and memory. Therefore, intensive studies have been done to elucidate the mechanism of LTP and to search for drugs having effects on LTP production. So far, we have found that LTP in mossy fiber-CA3 system of guinea pig hippocampal slices was susceptible to some neurotransmitters and nootropics, which are shown to improve learning deficiency in rodents. In the present paper, we detailed recording devices, experimental procedures and analysis of data in our laboratory. Using this experimental system, the effects of cholinergic agents on LTP of field EPSP in a mossy fiber-CA3 system were examined. A muscarinic M1-receptor antagonist pirenzepine and an M2 antagonist, AF-DX 116, at an examined concentration inhibited and facilitated, respectively, the LTP induction with no change in field EPSP amplitude evoked by test stimuli in the absence of tetanus. Thus, our experimental methods described here appear feasible for developing medication for dementia.

Animals↗
PubMed1994

[Megaloblastic anemia due to folate deficiency associated with hereditary spherocytosis].

A 19 years old male admitted to our hospital with fever, abdominal pain in May 1991. Physical examination revealed anemia, jaundice and marked splenomegaly. Severe pancytopenia with macrocytic hyperchronic anemia was noted along with elevated LDH and reduced serum folate. Blood smear showed nucleated RBCs, but only few microspherocytes. Bone marrow showed erythroid hyperplasia with remarkable megaloblastic changes. Megaloblasts were negative for PAS stain. Chromosome analysis revealed normal karyotype. Erythroleukemia was suspected initially, but his general condition as well as hematological data improved following 10 units of RBC transfusion. Following brief folic acid supplements, numerous microspherocytes became evident, typical osmotic fragility test revealed a pattern for hereditary spherocytosis. These observations led us to the diagnosis of hereditary spherocytosis complicated by megaloblastic anemia due to folate deficiency. As he developed folate deficiency again 10 months later, splenectomy were performed. The anemia improved after splenectomy.

Adult↗
PubMed1994

[Cytological features and prognosis of megakaryoblastic leukemia].

Nine patients with acute leukemia showing 10% or more positive blast cells with platelet peroxidase (PPO) or CD41b were diagnosed as megakaryoblastic leukemia. Three patients transformed from myelodysplastic syndromes or myeloproliferative disorders. The PPO positivity ranged from 7 to 55% (median 45%), and that for CD41b was 1.6 to 67.0% (median 16.4%). Because electron microscopic myeloperoxidase or glycophorin A were also positive in some patients, and also because CD41b positivity was often discordantly lower than PPO positivity, a possibility of mixed leukemia demonstrating myeloid or erythroid differentiation was suggested in 6 of these cases. As for the treatment results, all 3 pediatric cases who received combination chemotherapy achieved complete remission (CR). Among 6 adult cases CR was obtained in only one patient to whom low-dose cytosine arabinoside was administered. The remaining adult patients who received combination chemotherapy died relatively early.

Adult↗
PubMed1994

[Imaging and clinical significance of hepatic portal venous gas seen in adult patients].

In 10 adult patients with hepatic portal venous gas (HPVG), the clinical significance of HPVG and the efficacy of X-ray computed tomography (CT) were evaluated. HPVG was associated with ischemic bowel disease (n = 3), trauma (n = 4), liver abscess (n = 1), sepsis (n = 1), and unknown etiology (n = 1). The diagnostic ability of CT for the detection of HPVG was far superior to that of plain abdominal radiograph. Of 9 patients who underwent CT, HPVG located in the left hepatic lobe in all patients, and also in right hepatic lobe in 7 patients. Gas could be recognized in the left lobe and the anterior segment of the right lobe more clearly than in the posterior segment of the right lobe because of its larger amount of intravenous collection. The mortality rate of our cases was 100%. Gas was demonstrated simultaneously in the portal vein radicles and hepatic veins on CT in 4 patients with no clinical evidence of sepsis, which suggested the possibility of intraparenchymal shift of gas from the portal vein into the hepatic vein. In a single case with sepsis, gas was noted in various vessels, including arteries, in addition to the portal venous system. The authors conclude that HPVG is still a grave sign in Japan and prompt appropriate treatment is required. CT may be of great value in the early detection of HPVG and may indicate its etiology.

Abdominal Injuries↗