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T Maeda

Publications and source records attributed to T Maeda.

At least 955 records · Page 53Linked to original sources
PubMed1990

[Analysis of brain CT in 120 patients with human cysticercosis].

A study on brain CT was made in 120 patients of human cysticercosis, which is a rare disease in Japan and clinical symptoms and laboratory data for the diagnosis were also discussed. From the point of therapeutic view, we proposed a new differentiation on brain CT of human cysticercosis, which is divided into two groups according to the alive or dead parasite. Furthermore, we proposed a new type named multiple large and small cysts type on brain CT. The idea of diagnostic standard was made integrating brain CT image, clinical symptoms and laboratory data.

Adolescent↗
PubMed1990

[Ultrasonographic analysis of splenomegaly in patients with sarcoidosis].

Thirty seven patients with sarcoidosis were examined using ultrasound (US) to determine the size of the spleen. A Spleen Index (SI) was employed to evaluate splenomegaly and the SI was calculated using long (a) and short (b) dimensions on the sectional splenotomogram (SI = a x b). In 21 (57%) of these patients the spleen was judged ultrasonographically to be enlarged (SI 30), but in only 3 was it palpable. The clinical records of patients with and without splenomegaly detected by US were compared. There were no differences between patients with or without splenomegaly in hematologic findings (peripheral blood and bone marrow) or blood chemistry; furthermore no patients with hypersplenism were seen. In immunological parameters, the serum immunosuppressive acid protein level was significantly (p less than 0.05) higher in patients with splenomegaly than in those without splenomegaly; however, there were no differences in serum angiotenins converting enzyme activity, serum lysozyme level, PPD skin test or bronchoalveolar lavage fluid analysis. The patients with splenomegaly had significantly higher evidence of increased uptake of 67-Gallium in lung fields and positive lung infiltrates in chest X-ray than those without splenomegaly (p less than 0.01, p less than 0.05). These data suggest that ultrasound is a promising diagnostic tool for the assessment of the size of the spleen and is useful to detect disease activity and extent of disease in sarcoidosis. Patients with sarcoidosis who had splenomegaly had more disseminated disease, especially pulmonary parenchymal disease, than did those without splenomegaly.

Adult↗
PubMed1990

Do the H2-receptor antagonists, cimetidine and famotidine, modify the degree of renal recovery following renal insult?

The effects of two different H2-receptor antagonists, cimetidine and famotidine, on the acute renal failure induced by 20 min of renal artery occlusion and gentamicin (240mg/kg BW, s. c., for 3 days) were investigated in Sprague-Dawley rats. The animals were treated with either cimetidine (80 or 160 mg/kg BW) or famotidine (4 or 8 mg/kg BW) mixed in the drinking water for 7 days. The low dose of cimetidine and famotidine did not alter the renal function in the absence of renal trauma. However, the high dose of cimetidine or famotidine decreased the GFR by 32% and 22%, whereas RPFR increased by 46% and 62%, and % FENa by 92% and 558%, respectively. The data for the renal function obtained 24 hrs after 20 min of renal ischemia demonstrated a decrease of 54% in GFR, a decrease of 47% in RPFR and an increase of 370% in %FENa over the non-ischemic control values (p less than 0.05). Cimetidine (80 mg/kg BW) or famotidine (4 mg/kg BW) did not modify the recovery of renal function following the ischemic insult, showing 55% and 539% decreases in GFR, 74% and 101% increases in RPFR, and 393% and 461% increases in %FENa over the non-ischemic control rats, respectively. Famotidine reduced the decrease in RPFR significantly during the recovery period following ischemia. In the gentamicin study, gentamicin treatment was found to lower the renal function significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗
PubMed1990

[Infection prophylaxis in patients with hematological malignancies (I)--Successful prophylaxis of Pneumocystis carinii pneumonitis with sulfamethoxazole-trimethoprim].

In a retrospective study to evaluate the efficacy of sulfamethoxazole-trimethoprim (SMX-TMP) for the prevention of Pneumocystis carinii pneumonitis, we studied 1760 patients wit hematological malignancies over a twenty-year period (1970-1989). 449 patients received oral SMX-TMP, most of all received 400 mg of SMX and 80 mg of TMP twice per day. None of the patients receiving SMX-TMP developed P carinii pneumonitis, whereas twenty-six (2.0%) of the 1311 patients who did not receive SMX-TMP developed P carinii pneumonitis (p less than 0.01). We found that the SMX-TMP was very effective in the prevention of P carinii pneumonitis in patients with hematological malignancies, and was well tolerated.

Administration, Oral↗
PubMed1990

Anatomical variation in mast cell nerve associations in the rat small intestine, heart, lung, and skin. Similarities of distances between neural processes and mast cells, eosinophils, or plasma cells in the jejunal lamina propria.

Several studies have indicated that mast cells occur in close proximity to enteric nerves in the gastrointestinal tract of rats, man, and other mammalian species, and such intimate associations have been proposed as one of the anatomical bases of communication between the immune and the nervous systems. However, the specificity of anatomical associations between enteric nerves and mast cells, as opposed to other bone marrow-derived or lymphoid cells normally present in mucosal sites, is unclear. We used transmission electron microscopy to quantify the distances between mast cells and neural processes (nerve terminals or axons) in the small intestinal mucosa, right atrium, skin, and pulmonary parenchyma of normal rats, and in the small intestinal mucosa and lung parenchyma of rats that had undergone hyperplasia of the mast cell populations in these sites as a result of infection with the nematode Nippostrongylus brasiliensis. In the jejunal mucosa of normal rats, 8.0% of mast cells occurred within 100 nm of neural processes and an additional 11.0% between 101 and 500 nm of these structures; the corresponding figures for eosinophils were 3.3% (N.S. vs. mast cell value) and 23.3% (p less than 0.05 vs. mast cell value) and for plasma cells were 8.5% and 14.6% (N.S. vs. mast cell values). In the right atrium, 1.2% of mast cells occurred within 100 nm and an additional 13.4% within 101 and 500 nm of neural processes, whereas no mast cells were observed within 500 nm of neural processes in the pulmonary parenchyma or ear skin. Infection with N. brasiliensis increased by 61% the proportion of mast cells within 500 nm of neural processes in the jejunal mucosa and resulted in the appearance of mast cells in close association with these structures in the jejunal muscularis propria, but had no effect on the proportion of mast cells within 100 or 500 nm of neural processes in the pulmonary parenchyma. Acetylcholine esterase staining demonstrated dense networks of neural processes in the three sites where some mast cells were closely associated with these structures (jejunal mucosa and muscularis, right atrium) but not in the pulmonary parenchyma or ear skin. Taken together, our findings indicate that mast cells occur in close proximity to neural processes in sites where these structures are abundant, but that anatomical associations as close as those between mast cells and neural processes can also occur between such structures and other bone marrow-derived cells (eosinophils) or lymphoid cells (plasma cells) resident in the small intestinal mucosa.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1990

Nerve supply to the posterior longitudinal ligament and the intervertebral disc of the rat vertebral column as studied by acetylcholinesterase histochemistry. I. Distribution in the lumbar region.

The nerve supply to the posterior longitudinal ligament (PLL) and the intervertebral disc (IVD) of the lumbar vertebra was investigated by acetylcholinesterase (AchE) enzyme histochemistry in the rat. The meningeal branch of the spinal nerve (the sinuvertebral nerve) enters the vertebral canal and divides into ascending and descending branches which fuse with those from adjacent vertebrae. They give off transverse branches, connecting with those from the opposite side to form the superficial nerve fibre network in the intervertebral segment, which spreads to the vertebral segment of the PLL. Apart from this superficial nervous network, many nerve fibres enter through the posterolateral portion of the annulus fibrosus (AF) and form a dense, fine nerve fibre network in the deep layer of the intervertebral portion of the PLL and the superficial layer of the AF. Nerve fibres and terminals cannot be found in the deep layer of the AF or the nucleus pulposus. In the central part of the deeper nerve network there are few nerve terminals whereas there are abundant free nerve endings in the peripheral zones. It is suggested that these abundant nerve fibres may be correlated with various functions characteristic of this region and that they may be important in the regulation of movement and posture in the vertebral column.

Acetylcholinesterase↗
PubMed1990

Nerve supply to the posterior longitudinal ligament and the intervertebral disc of the rat vertebral column as studied by acetylcholinesterase histochemistry. II. Regional differences in the distribution of the nerve fibres and their origins.

Regional differences of the distribution and the origin of the nerve fibres of the posterior longitudinal ligament (PLL) and the intervertebral disc (IVD) were investigated by acetylcholinesterase (AchE) enzyme histochemistry in the rat. The deeper nerve network was well-developed at the lower thoracic and the upper lumbar vertebral levels, but it was hardly seen at the mid-thoracic level. This difference can be correlated with the extensibility of the PLL. The experimental study revealed that the AchE-positive nerve fibres in the PLL and the IVD were mostly derived from the spinal ganglia, that the superficial nerve network was supplied by the spinal ganglia bilaterally and polysegmentally, and that the deeper nerve network was supplied bilaterally but unisegmentally.

Acetylcholinesterase↗
PubMed1990

[Diagnosis of mammary gland diseases using microwave thermography: a study on adjunctive diagnostic methods in relation to different factors in breast diseases].

Since 1982, a 4.7 GHz microwave radiometer has been used for diagnosis of mammary gland diseases by obtaining temperature information on the region surrounding deeply located tumors. The subjects comprised 95 cases of malignant tumors and 331 cases of benign tumors (total, 426 cases). The analysis of the diagnostic results showed a 91.3% specificity, 72.6% sensitivity, 70.4% predictability, and 87.1% accuracy. The method provides different information on temperatures from conventional infrared telethermography and contact thermography due to the tissue permeability of microwave. Utilizing a combination of conventional methods and microwave thermography (MWT), the diagnostic rate was found to be 94.7%, resulting in an accuracy improvement of approximately 10%. Various factors are investigated for their effects on MWT diagnosis. No significant difference was seen with respect to histologic types. Although significant difference was seen with respect to histologic types. Although significant difference was not observed in relation to the diameter of the tumor, the diagnostic rate in T1 cases, which was 75.0% using two conventional methods, was improved to 100% when combined with MWT. Tumor depth revealed no significant difference. Tumor vascular density showed a high correlation with temperature measured by MWT.

Adolescent↗
PubMed1989

Effects of sublingual nitrate in patients receiving sustained therapy of isosorbide dinitrate for coronary artery disease.

To examine the effects of sublingual isosorbide dinitrate (ISDN) in patients receiving sustained ISDN therapy, 24 patients with coronary artery disease were divided into 2 groups. Group C comprised 12 patients without sustained ISDN therapy and group N included 12 patients with sustained ISDN therapy. Before and during administration of sublingual ISDN in both groups, aortic systolic pressure, left ventricular end-diastolic pressure and coronary artery diameter were examined at cardiac catheterization. During sublingual ISDN, the aortic systolic pressure decreased by 20 +/- 6% (138 +/- 26 to 112 +/- 27 mm Hg, p less than 0.01) in group C and 10 +/- 6% (127 +/- 26 to 113 +/- 23 mm Hg, p less than 0.01) in group N (p less than 0.01, group C vs group N). The left ventricular end-diastolic pressure decreased by 65 +/- 16% (11 +/- 5 to 4 +/- 3 mm Hg, p less than 0.01) in group C and 43 +/- 14% (12 +/- 5 to 7 +/- 3 mm Hg, p less than 0.01) in group N (p less than 0.01, group C vs group N). During sublingual ISDN, the diameters of the proximal and distal segments of the left anterior descending and circumflex coronary arteries increased more significantly in group C than in group N (p less than 0.01, group C vs group N). Thus, sublingual ISDN produced less reduction of aortic systolic pressure and left ventricular end-diastolic pressure, and less dilation of coronary artery diameter in patients receiving sustained therapy with ISDN than in those without sustained therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Sublingual↗
PubMed1989

A novel cell adhesive protein engineered by insertion of the Arg-Gly-Asp-Ser tetrapeptide.

A tetrapeptide Arg-Gly-Asp-Ser (RGDS) has been shown to be a versatile cell recognition signal of extracellular matrix components for the interaction with cells. We introduced the RGDS tetrapeptide into a truncated form of protein A, a staphylococcal immunoglobulin-binding protein, by inserting an oligonucleotide cassette encoding the tetrapeptide into the coding region of the protein A expression vector pRIT2T. The mutagenized protein was capable of not only binding to immunoglobulin G but also mediating cell attachment and spreading onto an inert substrate. Cell adhesion mediated by the mutagenized protein was inhibitable by a synthetic peptide Gly-Arg-Gly-Asp-Ser but not by a related peptide Gly-Arg-Gly-Glu-Ser, confirming that the inserted RGDS tetrapeptide served as a recognition signal for cell adhesion. Furthermore, the RGDS-containing protein was capable of adhering cells onto an immunoglobulin-coated surface which could not by itself support cell adhesion. Thus, the cell adhesive and immunoglobulin binding activities of the mutagenized protein appear to function coordinately. The protocol described here is essentially applicable to any protein and, therefore, provides a general principle in tailoring novel multifunctional proteins having cell adhesive activity.

Amino Acid Sequence↗
PubMed1989

Monoamine oxidase-containing nerve fibers in the major cerebral arteries of rats.

The localization of monoamine oxidase (MAO) in nerve fibers associated with the major cerebral arteries in rats was studied using a new coupled peroxidation method modified by adding nickel ammonium sulfate at the electron microscopic level. MAO was, localized in some unmyelinated axons, both in the adventitia and in the periadventitial nerve bundles. Schwann cell cytoplasm encircling myelinated axons in the periadventitial nerve bundles also contained a MAO-reactive substance. The incidences of MAO-containing axons in the adventitial layer of the anterior cerebral, middle cerebral, internal carotid and basilar arteries were 32.3%, 29.5%, 29.6% and 21.1%, respectively. In the periadventitial nerve bundles, MAO activity was also demonstrated in 10.8% among unmyelinated axons. Preincubation with clorgyline, a specific inhibitor of MAOA, suppressed staining in the axons, both in adventitia and in periadventitial nerve bundles, but not in the Schwann cell cytoplasm. Conversely, preincubation with deprenyl, a specific inhibitor of MAOB, suppressed staining in the Schwann cell cytoplasm, but not in the axons. Therefore, MAO in the axons is regarded as MAOA and MAO in the Schwann cell cytoplasm as MAOB. In immunosympathectomized rats (anti-NGF-treated rats), MAO reactivity was suppressed in axons associated with cerebral arteries, but was retained in some Schwann cell cytoplasm. The results indicate that the MAO-containing unmyelinated axons coincide with the postganglionic noradrenergic ones. Thus, histochemical MAO staining may be utilized to study postganglionic sympathetic nerve fibers presumably innervating the major cerebral arteries at the electron microscopic level.

Adrenergic Fibers↗
PubMed1989

Type B monoamine-oxidase-containing cells and fibers in the cat hypothalamus demonstrated by an improved enzyme histochemical method.

The present study, using a diaminobenzidine (DAB)-coupled peroxidation method, examined the distribution and morphological characteristics of neuronal structures containing type B monoamine oxidase (MAO-B) in the cat hypothalamus. Large and intensely stained, distinctive MAO-B-positive cells, multipolar and with long dendritic arbors, were principally distributed in the ventral hypothalamus extending from A7 to A12.5 of the Horsley-Clarke plane. These cells were located caudally in the ventral surface of the brain including the tuberomamillary nucleus (TM) and the region surrounding the mamillary nuclei. Rostrally, they were aggregated in the area surrounding the fornix, particularly in the lateral perifornical region, and dispersed in the anterior mamillary nucleus, lateral hypothalamic area (HLA), and the medial tip of the entopeduncular nucleus. The most rostral positive cell group was identified in a narrow space between the optic tract and the entopeduncular nucleus at the A12.5 level. In addition to these large cells, the present study disclosed the presence of "small" to "very small" MAO-B-positive cells in the area surrounding the mamillary recess and the lateral part of the caudal arcuate nucleus. Distinct MAO-B-stained fibers were identified in all regions of the hypothalamus. A large number of thick labeled fibers were observed in the ventral hypothalamus including the TM and premamillary nucleus and posterior and lateral hypothalamic areas. A dense network of MAO-B-positive terminal-like fibers was observed in the dorsomedial nucleus where very small labeled cells were scattered. Many intensely stained thick and straight fibers were seen running ventrolaterally in the anterior part of the HLA and in the narrow space between the entopeduncular nucleus and optic tract. In the area of the tuber cinereum and the ventral part of the HLA, there were many positive fibers cut transversely, possibly projecting to the more anterior parts of the brain such as the diagonal band of Broca or septal nuclei.

Animals↗
PubMed1989

The DJH complex remains active in recombination to VH segments after the loss of mu-chain expression in mu-positive pre-B cells.

AT11-2 is an Abelson virus-transformed B precursor cell line which is capable of differentiating Ig- from mu+ cells via functional recombination of VH segments to preexisting DJH complexes. We describe here that after a mu+ subclone (VDJ+/DJ) generated from Ig- AT11-2 (DJ/DJ) cells by in vitro functional VH to DJH recombination subsequently lost mu-chain expression either by the recombination of a pseudo VH segment to the VHDJH+ allele or by the deletion of VHDJH+ allele, a novel productive joining of VH segments to the preexisting DJH complex occurred. These results indicated that VH to VHDJH rearrangement was not suppressed in mu-chain producing cells and that the DJH complexes still remained active in the recombination to VH segments after the loss of mu-chain expression. Our results may also suggest that VH to DJH rearrangement, but not VH to VHDJH rearrangement, is suppressed in mu-chain producing cells to maintain allelic exclusion. Our cell differentiation system should continue to be valuable for elucidating the mechanism of suppression and associated implications regarding allelic exclusion.

Amino Acid Sequence↗
PubMed1989

Alternative usage of different poly(A) addition signals for two major species of mRNA encoding human aromatase P-450.

Two cDNA clones for human placental aromatase P-450 (P-450AROM) have been isolated and sequenced. The insert of one clone (2894 bp) contains an open reading frame encoding a protein consisting of 503 amino acid residues together with a 49 bp 5'-untranslated stretch and a 1336 bp 3'-noncoding region to which a poly(A) tract is attached. Three potential poly(A) addition signals are detected in this 3'-noncoding region. The other clone contains a shorter cDNA insert, the nucleotide sequence of which overlaps with most of the sequence of the longer cDNA insert (nucleotides 36-2355) except for one nucleotide substitution. The 3'-noncoding region of this shorter cDNA is only 846 bp in length but a poly(A) tract is also attached to its 3'-terminus. Northern blot analysis of human placental RNA reveals the presence of two major mRNA species of 3.4 and 2.9 kb when probes excised from the overlapping region of these two cDNAs are employed. The 2.9 kb mRNA is not detected, however, when a fragment of the non-overlapping region of the longer cDNA is used as a probe. It is therefore concluded that the two major species of P-450AROM mRNA are formed as a consequence of alternative processing of precursor mRNA(s).

Amino Acid Sequence↗
PubMed1989

[Experimental study of the antitumor effect of Z-100 in the treatment of MM46 tumor transplanted in C3H/He mice. 2. Effect of the combination therapy of radiation and long term administration of Z-100].

Female C3H/He mice aged 14 weeks with transplanted MM46 tumor were used to investigate the effect of an immunomodulator, Z-100 (an arabinomannan lipid extracted from Mycobacterium tuberculosis strain Aoyama B) combined with local irradiation of 30 Gy (3,000 rad). Daily doses of 5 micrograms, 50 micrograms and 500 micrograms/kg of Z-100 were injected intramuscularly for 14 consecutive days after irradiation, and 2 times a week for 6 weeks thereafter. The antitumor effect was evaluated by the changes in tumor volume and survival curves. In groups administered 50 micrograms and 500 micrograms/kg of Z-100, tumor growth decreased significantly compared with the control group (radiotherapy group). Concerning survival rates of each group of mice, there were no marked differences between Z-100 administered groups and the control group. To clarify the mechanisms of action of Z-100, the changes in the lymphocyte subsets infiltrated into tumor tissue after Z-100 treatment were analysed immunohistochemically using monoclonal antibodies, anti-Thy 1.2, anti-Lyt-1, anti-Lyt-2, anti-L3T4, MAS034b and MAS053c and avidin-biotin-peroxidase complex method (ABC method). In the findings of immunohistochemical studies, differences were hardly observed between groups administered Z-100 and groups treated with radiation only. From these results, it was concluded that immunological effects of Z-100 resembled that of radiotherapy on the topical tumor tissue.

Animals↗
PubMed1989

The ultrastructure of Ruffini endings in the periodontal ligament of rat incisors with special reference to the terminal Schwann cells (K-cells).

The Ruffini endings and associated cells in the periodontal ligament of rat incisors were investigated by means of immunohistochemistry for glia-specific S-100 protein and electron microscopy. Numerous Ruffini endings, which were immunoreactive for S-100 protein as well as for neurofilament protein, were distributed in the alveolus-related part of the lingual periodontal ligament. In electron microscopy, the Ruffini endings displayed expanded axoplasmic spines filled with a large number of mitochondria and neurofilaments; some of the spines directly contacted the surrounding collagen fibers via fingerlike projections. The axoplasmic spines and Schwann sheath, for the most part, were covered alternately by single or multiple layers of the basal lamina. Several rounded cells showing S-100 immunoreactivity occurred in the vicinity of the Ruffini endings. The rounded cells associated with Ruffini endings possessed a kidney-shaped nucleus and enveloped the axoplasmic spines with their cytoplasmic processes. From these morphological features, the cells in question were identified as the K-cells described by Everts et al. (1977). These K-cells developed Golgi apparatus and rough endoplasmic reticulum, suggesting active synthesis of proteins. Immunohistochemistry at the electron microscopic level revealed an intense immunoreactivity for S-100 protein in the cytoplasm of the K-cell and led to a conclusion that the K-cells were terminal Schwann cells associated with Ruffini endings, presumably corresponding to the lamellar cells in the inner bulb of sensory corpuscles.

Animals↗