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S Shimada

Publications and source records attributed to S Shimada.

At least 289 records · Page 16Linked to original sources
PubMed1991

Dopamine transporter: expression in Xenopus oocytes.

Xenopus oocytes can express biologically relevant transport activity after injection of mRNAs encoding several carrier molecules. mRNA from PC12 cells, as well as transcripts from a rat ventral midbrain library, can be expressed in these oocytes and allow them to display pharmacologically specific dopamine uptake. mRNA-injected oocytes incubated with tritiated dopamine contain tritiated dopamine and metabolites; lower amounts of radiolabeled dopamine and more radiolabeled metabolites are found in oocytes co-incubated with cocaine or in water-injected oocytes. Tritiated dopamine uptake into mRNA-injected oocytes is time, sodium, and temperature dependent. It is blocked by cocaine and mazindol, but not by haloperidol. It is not found after injection of mRNA from other brain regions. A size-selected rat midbrain library constructed in the plasma vector pCDM8 yields mRNA transcripts whose injection into oocytes causes cocaine-blockable [3H]dopamine uptake. These findings provide an assay for purification of the dopamine transporter cDNA by sib selection techniques.

Adrenal Gland Neoplasms↗
PubMed1991

Striatal calcitonin gene-related peptide-like immunoreactive afferents from the regions ventral and medial to the medial geniculate nucleus of rats.

The sources of fibers with immunoreactivity to calcitonin gene-related peptide in the caudal portion of the caudate-putamen were investigated in animals treated by a knife cut, a tracer injection, or an electrolytic lesion of regions ventral and medial to the medial geniculate nucleus. Hemitransection of the brain just caudal to the caudate-putamen decreased ipsilaterally calcitonin gene-related peptide-like immunoreactivity in the caudal portion of the caudate-putamen, suggesting that calcitonin gene-related peptide-like immunoreactive fibers in the caudate-putamen originated from neurons in the area caudal to the caudate-putamen. Some calcitonin gene-related peptide-like immunoreactive neurons in the regions ventral and medial to the medial geniculate nucleus, including the peripeduncular, posterior intralaminar and suprageniculate nuclei, were labeled ipsilaterally with a retrograde tracer after an injection into the caudal portion of the caudate-putamen. In addition, an electrolytic lesion of calcitonin gene-related peptide-like immunoreactive neurons in the regions ventral and medial to the medial geniculate nucleus decreased the number of calcitonin gene-related peptide-like immunoreactive fibers in the ipsilateral caudal portion of the caudate-putamen. These results suggest that some cells containing calcitonin gene-related peptide in several posterior thalamic nuclei project to the caudal caudate-putamen.

Animals↗
PubMed1991

Triacylglycerol lipase mediated release of arachidonic acid for prostaglandin synthesis in rabbit kidney medulla microsomes.

The effect of triarachidonin on the synthesis of prostaglandins in rabbit kidney medulla microsomes was examined. Medulla microsomes were incubated with triarachidonin in 0.1 M--Tris/HCl buffer (pH 7.0) containing reduced glutathione and hydroquinone and the formed prostaglandin E2, prostaglandin F2 alpha and prostaglandin D2 were measured by high-pressure liquid chromatography using 9-anthryldiazomethane for derivatization. The addition of triarachidonin (1-10 microM) stimulated prostaglandin formation in a dose-dependent manner. Under our incubation conditions rabbit kidney medulla was found to produce prostaglandin E2 mainly. When arachidonic acid, instead of triarachidonin, was added to the incubation mixture of microsomes, the identical profile of prostaglandin products was obtained. When the pH of the reaction mixture was changed from 7.0 to 8.0, the rate of triarachidonin-induced prostaglandin E2 formation was approximately 60% of that observed at pH 7.0. Studies utilizing Ca2+ and EGTA revealed that triacylglycerol lipase of kidney medulla is independent of Ca2+. The addition of epinephrine made the stimulatory effect of triarachidonin on prostaglandin E2 formation more pronounced. These results suggest that epinephrine-activated triacylglycerol lipase is present in the renomedullary microsomes, and this enzyme activity is a potential mediator of release of arachidonic acid for prostaglandin synthesis in the kidney medulla.

5,8,11,14-Eicosatetraynoic Acid↗
PubMed1991

A case of cutaneous squamous cell carcinoma associated with sporadic porphyria cutanea tarda due to liver disorder after Schistosoma japonicum infection.

A 56-year-old man suffered from cutaneous squamous cell carcinoma (cutaneous SCC) which occurred on a cutaneous lesion of sporadic porphyria cutanea tarda (sporadic PCT). His liver function decreased from the time he was infected with Schistosoma japonicum at the age of 10. He drank a little alcohol. Erythematous maculae with blisters or erosions occurred on sun-exposed areas of his skin when he was 52. His urine continued to be red. After detailed examinations including liver biopsy, he was diagnosed as having sporadic PCT due to liver disorder after infection with Schistosoma japonicum. At the age of 56, a small red papule arose on his right earlobe at the site of a sporadic PCT lesion. The papule rapidly enlarged with ulceration; this completely destroyed his right earlobe, which was covered with odoriferous yellow-white necrotic tissue. The tumor then extended to his right preauricular area with ulceration. A skin biopsy confirmed well-differentiated cutaneous SCC. The association of cutaneous SCC with sporadic PCT has not been previously reported; we think that the association is significant. Such an occurrence may have been induced by either direct or indirect effects of ultraviolet light or a scar formed by the sporadic PCT.

Animals↗
PubMed1991

In-vivo administration of recombinant IL-2 increases the number of Thy-1+ dendritic epidermal cells.

The number, morphology and response of Thy-1+ dendritic epidermal cells to recombinant interleukin-2 (rIL-2) were investigated in young and aged mice. The Thy-1+ dendritic cells in the aged mice continued to express T-cell receptor (TCR) gamma/delta but differed morphologically from those of the young mice. The aged mice had 50% fewer cells than the young ones. In the rIL-2 treated mice all the Thy-1+ cells were expressed as TCR gamma/delta and exposure to rIL-2 increased the number of these cells in a time- and dose-dependent manner when given systemically and locally. In the aged mice daily injection of rIL-2 increased the number of Thy-1+ dendritic cells within 2 weeks to almost that of young mice, however they had a lower response in the earlier stage. Nude mice showed no response to rIL-2.

Abdomen↗
PubMed1991

[Myelination in very low birth weight infants--evaluation by MRI].

The prognostic significance of cerebral myelination was evaluated with magnetic resonance imaging (MRI) in very low birth weight infants. Myelination was graded in two specified sites, optic radiation and corpus callosum, based on the stages of normal term babies and healthy premature infants. The subjects were 30 preterm infants weighing less than 1,500 gm at birth. MRI was performed at 4 to 7 months (corrected age). The normal myelination stage was seen in 18 cases, while a delayed stage was noticed in 12 cases. In the normal myelination group, only 1 case (6%) had handicaps. In the delayed myelination group, 8 cases (67%) had handicaps. Our results showed that delayed myelination was closely related to a poor prognosis. We believe that MRI would be a very good imaging modality for predicting the outcome of very low birth weight infants, particularly in terms of evaluation of myelination.

Brain↗
PubMed1991

[Recent progress in the treatment of oral and pharyngeal cancer].

Today, in the treatment of oral cancer, combined resection and reconstructive surgery has shown marked progress. Especially, the surgical procedures of bone graft after mandibulectomy have been seen widespread application. In the treatment of nasopharyngeal cancer, adjuvant chemotherapy after therapeutic dose of irradiation indicates a better survival rate than radiation alone, and in advanced nasopharyngeal cancer, a wide resection is effective for cure. In the surgical treatment of hypopharyngeal cancer, by the immediate reconstruction of pharynx with jejunum, patients can eat orally in a short time. The most important problem in the treatment of head and neck cancer is development of effective chemotherapy against distant metastases.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

[Surgical treatment of cancer of the biliary tract and gall bladder].

With the advances in various kinds of diagnostic methods and improvement of operative technique, operations for cancer in biliary tract have recently increased, however, the prognosis has been unsatisfied. During the past 25 years, 495 cases with carcinoma of biliary tract (ca of gall bladder 175 cases, ca of bile duct 201, and ca of papilla vater 105) were operated. The resectability rate was 66% (62% in gall bladder, 62% in bile duct, 84% in papilla vater). Among the lesions in bile duct, the resectable rate in lower bile duct was better than the other site in bile duct. The late results in ca of bile duct, especially in the lesion of upper bile duct were still poor, however, the 5-years survival rate in ca of gallbladder or papilla vater carcinoma was 61% or 56%, respectively. For the further improvement of the surgical results, the sufficient resection of the intrahepatic bile duct in ca of bile duct should be performed, and in gall bladder carcinoma when tumor extends into the neck of gall bladder, bile duct should be resected. In advanced carcinoma, the appropriate hepatectomy or bile duct resection should be considered in proportion to the operative influence and the extension of the tumor.

Biliary Tract Neoplasms↗
PubMed1990

A fourth subunit is present in cytochrome c oxidase from the thermophilic bacterium PS3.

A new putative subunit was found in cytochrome c oxidase (aa3-type) of the thermophilic bacterium PS3. The N-terminal amino acid sequence of this approximately 12 kDa protein coincides with the deduced sequence of an open reading frame found downstream from the gene encoding subunit I of the PS3 cytochrome oxidase [(1988) J. Biochem. 103, 606-610]. This small hydrophobic protein, composed of 109 amino acid residues after the initial methionine residue has been processed, shows homology with the subunit IV (cyoD product) of cytochrome bo-type quinol oxidase of Escherichia coli.

Amino Acid Sequence↗
PubMed1990

Freshly isolated Thy-1+ dendritic epidermal cells express T cell receptor gamma delta-CD3.

Within murine epidermis exists a population of Thy-1+ DEC which express membrane Thy-1 antigen, but lack CD8 or CD4 antigen. We examined freshly obtained non-cultured Thy-1+ DEC both by immunofluorescence and by biochemical techniques to identify the protein products of the T cell receptor (TCR) and the associated CD3 complex on these cells. Virtually all of the Thy-1+ DEC are brightly positive in CD3 expression with immunofluorescence using the monoclonal antibody 145-2C11. By immunoprecipitation, using this same antibody and polyclonal anti-TCR-gamma antibody, the only TCR heterodimer detected on the freshly isolated Thy-1+ DEC is the gamma delta heterodimer. These findings suggest that in the phenotype and TCR expression, Thy-1+ DEC are analogous to CD8-, CD4- early fetal thymocytes.

Amino Acid Sequence↗
PubMed1990

Thy-1-positive dendritic epidermal cells contain a killer protein perforin.

The killer cell characteristics of Thy-1-positive dendritic epidermal cells (Thy-1+ DEC) were examined. Four Thy-1+ DEC clones which were established from athymic nude mice exhibited spontaneous or lectin-redirectable cytotoxic activity against some murine tumor cell lines in a 4 h 51Cr-release assay. A colorimetric assay for benzyloxycarbonyl-L-lysine-thiobenzyl ester esterase revealed a strong serine esterase activity expressed in all cell clones. In addition, Northern blot analysis using a murine perforin cDNA probe revealed that all four Thy-1+ DEC clones expressed abundant mRNA for perforin, as do most killer T cells. More importantly, immunocytochemical staining with an anti-perforin monoclonal antibody revealed that not only all four Thy-1+ DEC clones but also a part of freshly isolated Thy-1+ DEC from normal and nude mice contained perforin. These results demonstrate that Thy-1+ DEC exhibit typical killer cell characteristics in vitro and in vivo. These data also suggest that Thy-1+ DEC may play a cytotoxic role in protecting the integrity of skin from infection or neoplastic transformation.

Animals↗
PubMed1990

Nucleotide sequence of the gene coding for four subunits of cytochrome c oxidase from the thermophilic bacterium PS3.

The gene coding for four subunits of cytochrome aa3-type oxidase was isolated from a genomic DNA library of the thermophilic bacterium PS3 and sequenced. The N-terminus of each subunit was also sequenced to verify the initiation site of the reading frame. The deduced amino acid sequences contained 615 amino acid residues for subunit I (CO1/caaB product), 333 residues for subunit II (CO2/caaA product), 207 residues for subunit III (CO3/caaC product), and 109 residues for subunit IV (CO4/caaD product) after processing. Re-examination of the sequencing of caa revealed a longer open reading frame for CO1, which contains 14 transmembrane segments instead of 12 [Sone et al. (1988) J. Biochem. 103, 606-610], although the main portions of the sequences constituting cytochrome a (FeA), cytochrome a3 (FeB), and CuB are correct. PS3 CO2 has an additional sequence for cytochrome c after the CuA binding protein portion with 2 transmembrane segments, which is homologous to the mitochondrial counterpart. PS3 CO3 has DCCD-binding glutamyl residues but contains only 5 transmembrane segments, unlike the mitochondrial counterpart, which has 7 segments. The subunits of PS3 cytochrome oxidase (aa3-type) show clear similarity in amino acid sequences with those of cytochrome bo-type oxidase from Escherichia coli as well, in spite of the difference of hemes. PS3 CO3 and CO4 are much more similar to E. coli CO3 and CO4 than to mitochondrial CO3 and CO4, respectively.

Amino Acid Sequence↗
PubMed1990

Effect of exogenous surfactant on the development of bronchopulmonary dysplasia in a baboon hyaline membrane disease model.

To test the effect of exogenous surfactant on the evolution of histopathologic changes of bronchopulmonary dysplasia (BPD), we conducted a study in a premature baboon hyaline membrane disease model. One hundred mg/kg bovine surfactant sonicated in saline or 3 ml/kg saline placebo was instilled via the trachea at about 10 min of age. The clinical status and physiologic changes were monitored for 9 days, and pulmonary histopathology was evaluated after death. Compared to the control, the surfactant-treated animals showed a significant improvement in arterial/alveolar oxygen ratio and pulmonary compliance, facilitating rapid weaning from assisted ventilation. Lung histology revealed that pulmonary parenchyma expanded 70% to 95% without features of early BPD. Dysplastic maturation, air trapping, or cellular atypia was not seen. In contrast, lung histology in the control group revealed alveolar expansion less than or equal to 50%, basal cell hyperplasia in the bronchial and bronchiolar epithelium, dysplastic maturation with cellular atypia, extensive epithelial erosion, and type II cell hyperplasia, all features of early BPD. The results of this study suggest that in the premature baboon model, exogenous surfactant therapy improves pulmonary functional abnormalities and lessens the histologic features of BPD, perhaps because of rapid weaning and reduced barotrauma.

Animals↗
PubMed1990

Chest radiographic course after exogenous surfactant therapy in baboons with respiratory distress syndrome.

Exogenous surfactant materials have been used under a variety of treatment protocols in cases of neonatal respiratory distress syndrome (RDS). To evaluate the differences in radiologic changes that follow either an early or late therapy with exogenous bovine surfactant, we reviewed 189 serially obtained chest radiographs from 48 premature baboons with RDS studied under different treatment regimen. Twenty-six animals were controls (100 chest films), and 22 received 100 mg/kg bovine surfactant instilled via the trachea in three study protocols (89 chest films). Surfactant was given within 10 min of birth in one group and at 2 h of age in the other. In 25/26 controls, radiologic evidence of severe RDS was seen by 2 h of age; these changes persisted in 15 animals at 24 h. By contrast, a rapid clearing of radiologic features of RDS was seen following surfactant instillation in all 22 (100%) animals within 4 h, but one (4.5%) of these 22 deteriorated at 9 h of age. Pulmonary interstitial emphysema (PIE) was seen in 9/26 (34.6%) and pneumothorax in 5/26 (19.2%) control animals, while 1/22 (4.5%) surfactant-treated animals developed PIE, and none had pneumothorax. The presence of a shunt via the patent ductus arteriosus did not affect radiographic findings in 20 animals studied by contrast injection. Therapy for patent ductus arteriosus (PDA) also had no substantial influence on the radiographic findings, or with regard to the pulmonary course. Radiographic clearing of RDS occurred approximately 18 to 20 h prior to the improvement in pulmonary compliance.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗