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Biomedical subjects

H Uchida

Publications and source records attributed to H Uchida.

At least 343 records · Page 19Linked to original sources
PubMed1993

Application of the bromophenol blue (BPB) staining method to rat fetal cartilage previously stained with alizarin red S.

The application of a convenient bromophenol blue (BPB) cartilage staining method on rat fetal skeleton, previously stained with alizarin red S, was investigated. This staining method made it possible to observe uncertain cartilage anomalies and unossified caudal vertebrae, which were poorly detected by single staining with alizarin red S. Namely, the anomaly of chondral rib bifurcation was detected and the number of unossified caudal vertebrae in rat fetuses was demonstrated as being identical with adult rat caudal vertebrae. The BPB staining has the notice to make the pH 4 adjusted specimens and has the advantage of fading with water or ethanol at pH 8 without discoloration of alizarin red S on the bones.

Animals↗
PubMed1993

Cellular immunocompetence in aortitis syndrome.

Cellular immunocompetence was investigated in 17 cases of aortitis syndrome (3 active, 14 inactive stage). Both the active and inactive groups demonstrated significantly lower interleukin-2 (IL-2) production than healthy volunteers. The active aortitis syndrome group produced significantly more interleukin-1 beta (IL-1 beta) than the inactive group. The proportion of CD11b+ CD8+ cells was significantly lower in the active aortitis syndrome group. Further, the proportions of CD11b- CD8+ cells and CD57+ CD16- cells in the aortitis syndrome patients were significantly higher than the healthy volunteers. These results suggest that there are intrinsic qualitative abnormalities in the T cells that produce IL-2 in aortitis syndrome. Pathogenesis of aortitis syndrome is considered as follows: during the active stage, diminished IL-2 production impairs differentiation and proliferation of suppressor T cells, thus creating abnormalities in the inhibitory functions of immunoregulation and promoting the proliferation of cytotoxic T and natural killer (NK) cells. This presumably initiates inflammation of the aorta and/or artery.

Adult↗
PubMed1993

Spinal epidural oxygen partial pressure and evoked spinal cord potential in relation to the severity of spinal ischemia during cross-clamping of the thoracic aorta.

Experiments were undertaken to determine the relationship between evoked spinal cord potential (ESP) and the partial pressure of oxygen in tissue in the epidural space (E-pO2) during aortic clamping. Eighteen adult mongrel dogs were studied as follows. In group I (n = 6), the descending thoracic aorta was clamped partially at the proximal site for 15 min to maintain the distal arterial pressure at 60, 40, and 20 mmHg consecutively at 15 min intervals. In group II (n = 6), the descending thoracic aorta was clamped proximally for 30 min. In group III (n = 6), the descending thoracic aorta was cross-clamped at proximal and distal sites for 30 min. Postoperative complete paraplegia was observed in 4 of 6 dogs in group III, but none in group II. The change in ESP with aorta cross-clamping was very mild in groups I and II. Transient increases and decreases in the ESP amplitude were observed in group III. The decrease of E-pO2 correlated well with the distal arterial pressure, and a rapid return to baseline of the E-pO2 was observed after declamping. The E-pO2 changed in response to spinal ischemia more rapidly than did ESP in all groups. The critical level of E-pO2 was 50 mmHg or a 40% decrease from baseline. Because the ESP reflects spinal function and the E-pO2 reflects spinal blood pressure, we propose that combined recording of ESP and E-pO2 would improve spinal monitoring during thoracic aortic surgery.

Animals↗
PubMed1993

Novel antitumor antibiotics, saptomycins. I. Taxonomy of the producing organism, fermentation, HPLC analysis and biological activities.

Streptomyces sp. HP530 was found to produce novel antitumor antibiotics, saptomycins, closely related to the pluramycin-group and was further found to mutate frequently. The natural mutant produced several new saptomycins as determined by HPLC analyses. We isolated saptomycins A, B, C1, C2 and F from the parent strain and saptomycins D, E, G and H from the mutant. The saptomycins showed antimicrobial activities and potent antitumor activities against human or murine tumor cell lines in vitro and against Meth A fibrosarcoma in vivo. In particular, saptomycin D was most effective component in vivo of all saptomycins.

Aminoglycosides↗
PubMed1993

Novel antitumor antibiotics, saptomycins. II. Isolation, physico-chemical properties and structure elucidation.

A complex of novel antitumor antibiotics related to the pluramycin-group was isolated from the fermentation of actinomycete, named Streptomyces sp. HP530. The producing strain mutated frequently. The products isolated from the parent strain were designated saptomycins A, B, C1, C2 and F, while those of the mutant were named saptomycins D, E, G and H. These structures were elucidated by several NMR spectral analyses and other spectroscopic experiments.

Aminoglycosides↗
PubMed1993

Novel cytocidal compounds, oxopropalines from Streptomyces sp. G324 producing lavendamycin. I. Taxonomy of the producing organism, fermentation, isolation and biological activities.

In the course of our investigation aimed at the discovery of novel antitumor antibiotics from microorganisms, Streptomyces sp. G324 was found to produce the antitumor antibiotic, lavendamycin, and also, to yield the novel beta-carboline compounds, oxopropalines. We isolated five compounds as oxopropalines A, B, D, E and G. Oxopropalines B, D and G showed cytocidal activities against human or murine tumor cell lines in vitro.

Animals↗
PubMed1993

Novel cytocidal compounds, oxopropalines from Streptomyces sp. G324 producing lavendamycin. II. Physico-chemical properties and structure elucidations.

Novel cytocidal compounds designated oxopropalines A, B, D, E and G were isolated from the fermentation of an actinomycete named Streptomyces sp. G324, a strain that also produced an antitumor antibiotic, lavendamycin. All these compounds possessed a beta-carboline chromophore. The structures of the oxopropalines were elucidated by several NMR spectral analyses and other spectroscopic experiments.

Antibiotics, Antineoplastic↗
PubMed1993

Direct evidence of plastid DNA and mitochondrial DNA in sperm cells in relation to biparental inheritance of organelle DNA in Pelargonium zonale by fluorescence/electron microscopy.

The fate of plastid DNA and mitochondrial DNA was followed during spermatogenesis in thin sections of the pollen grains in Pelargonium zonale by epifluorescence microscopy, after staining with 4'-6-diamidino-2-phenylindole (DAPI), by the combination of fluorescence and electron microscopic images by color image processor, and by immunogold electron microscopy. DAPI-stained thin sections showed that there are two different types of fluorescent spots due to organelle DNA in the cytoplasm of generative cells and sperm cells: spherical spots that emit strong fluorescence (SF spots) and a ring-shaped group of tiny spots that emit a pale fluorescence (RG spots). The RG spots correspond to peanut-shaped refractive dense bodies under a phase-contrast microscope. Combination of the fluorescence and electron microscopic images by a color image processor showed that SF spots are not emitted from peanut-shaped electron-dense bodies but are from small spherical granules with cristae-like lamellae. Immunogold electron microscopy using ultrathin sectioning showed that the small spherical granules are mitochondria with typical cristae and that the peanut-shaped electron-dense bodies are plastids. The results clearly indicate that mitochondria and plastids with DNA molecules are present in the cytoplasm of sperm cells. The presence of these plastid DNA molecules may be responsible for the biparental inheritance of plastids. In addition, mitochondrial DNA may also show biparental inheritance.

DNA, Mitochondrial↗
PubMed1993

Pharmacological profiles of the new histamine H2-receptor antagonist N-ethyl-N'-[3-[3-(piperidinomethyl)phenoxy] propyl] urea.

The histamine H2-receptor antagonistic activity and antisecretory effects of KU-1257 (N-ethyl-N'-[3-[3-(piperidinomethyl) phenoxy]propyl]urea, CAS 120958-90-9) were studied. The Ki values of KU-1257, roxatidine acetate, famotidine and cimetidine for the inhibition of [3H]-tiotidine binding to guinea-pig cerebral cortex were 0.040, 0.13, 0.016 and 0.40 mumol/l, respectively. The KB values of KU-1257, roxatidine acetate, famotidine and cimetidine for the antagonism against histamine-induced positive chronotropic response of isolated guinea-pig right atrium were 0.041, 0.14, 0.031 and 0.51 mumol/l, respectively. In pylorus-ligated rats, KU-1257, roxatidine acetate and famotidine inhibited gastric acid secretion with respective intraduodenal ID50 values of 12.3, 18.5 and 0.45 mg/kg. In dogs with Heidenhain pouch, the ID50 values of KU-1257 for the inhibition of acid output stimulated by histamine, tetragastrin and meat meal were 0.08, 0.39 and 0.15 mg/kg p.o., respectively. KU-1257 was 2-3 times more potent than roxatidine acetate regardless of secretagogues and twice less than famotidine in meat meal stimulation. These results indicate that KU-1257 is a potent and competitive histamine H2-receptor antagonist.

Animals↗
PubMed1993

Healing-promoting action of the new histamine H2-receptor antagonist N-ethyl-N'-[3-[3-(piperidinomethyl)phenoxy]propyl]urea with dual action on chronic gastric and duodenal ulcers induced by acetic acid in rats.

Healing-promoting actions of KU-1257 (N-ethyl-N'-[3-[3-(piperidinomethyl)phenoxy]propyl]urea, CAS 120958-90-9) were investigated in chronic gastric and duodenal ulcer models induced by acetic acid in rats and the effects were compared with those of famotidine and roxatidine acetate by gross or histological evaluation. KU-1257 markedly promoted the well-balanced healing of gastric ulcer at oral doses of 10-50 mg/kg x 2/day, as evidenced by the reduction of ulcer, regeneration of mucosa and proliferation of connective tissue. KU-1257 caused an increase in gastric mucus secretion in the regenerated mucosa around the gastric ulcers. Famotidine and roxatidine acetate failed to promote the healing of gastric ulcers even at 100 mg/kg x 2/day p.o. KU-1257 also significantly accelerated the healing of acetic acid-induced duodenal ulcers as well as famotidine and roxatidine acetate. These results indicate that KU-1257 is characterized by a potent promoting action on the healing of chronic ulcers, suggesting that the increase in gastric mucus secretion might be associated with the antiulcer actions of KU-1257 in part.

Acetates↗
PubMed1993

[Descending thoracic aorto-aortic bypass grafting for coarctation of the aorta in an adult combined with a cerebral arterial aneurysm--a case report].

Coarctation of the aorta (CoA) in adults is often accompanied by hypertension, but CoA combined with a cerebral arterial aneurysm is rare. We performed successfully descending thoracic aorto-aortic bypass grafting for CoA in an adult who had a cerebral bleeding and a cerebral arterial aneurysm. The patient was a 46-year-old female who had the history of hypertension. She suddenly suffered from left hemiparesis due to cerebral bleeding, then a left middle cerebral arterial aneurysm and CoA were detected at the same time. Aortography showed that the internal diameter of the portion of the coarctation was 2.8 mm and the poststenotic dilatation was prominent. The peak systolic pressure gradient across the coarctation was 60 mmHg. We took the precedence of the surgical repair for CoA over that for the cerebral arterial aneurysm, because her cerebral arterial aneurysm was judged to have less risk to rupture from the viewpoint of its size and shape by neurosurgeons. We performed proximal descending thoracic aorto-distal descending thoracic aortic bypass grafting with a woven double velour graft of 16 mm in internal diameter and 9.5 cm in length. Intraoperative cerebrovascular hypertension can be avoided by this procedure. Furthermore the peak systolic pressure gradient has disappeared immediately after grafting. In general, the coarctectomy with direct end-to-end anastomosis is prevalent for CoA in adults. On the other hand, the descending thoracic aorto-aortic bypass grafting for CoA in adults has rarely been reported.(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta, Thoracic↗
PubMed1993

[Effect of human recombinant erythropoietin (Epo) on cellular Ca2+, Na+, and K+ regulation of vascular smooth muscle cells grown in vitro--a new insight into the pathogenesis of Epo induced hypertension].

To gain an insight into the effect of erythropoietin (Epo) upon cation transporters and cytosolic free Ca2+ concentration ([Ca2+]i) of vascular smooth muscle cells (VSMC), we studied whether 1) Epo, per se, alters Ca2+ Na+, K+ fluxes and [Ca2+]i of VSMC, and 2) Epo may modify the effect of endothelin (ET-1). Using serially passaged quiescent cultured VSMC, the following results were obtained. 1) Epo had no direct effect on steady state Na(+)-K+ transporters (Na(+)-K+ pump, Na(+)-K+ cotransport and Na(+)-H+ antiport). 2) ET-1 alone substantially stimulated Na(+)-K+ pump, Na(+)-H+ antiport and 45Ca uptake, although these effects were not potentiated in the presence of Epo. 3) Epo alone substantially stimulated 45Ca uptake, leading to an increase in [Ca2+]i, which effect was not seen in Ca2+ deficient medium, and was partially inhibited with diltiazem but not with TMB-8. 4) Even in the presence of Epo, ET-1 and angiotensin II (A II) had substantial stimulatory effect on [Ca2+]i of cultured VSMC. The present data indicate that Epo, per se, elicits an increase in [Ca2+]i of VSMC through the stimulation of inward Ca2+ flux without affecting Na(+)-K+ transporters. In contrast, Epo did not potentiate ET-1's stimulatory effect on the transporters. Although the effect of Epo was subtle compared to ET-1 and A II, it may alter an overall characteristic of vascular smooth muscle cell contractility, possibly leading to blood pressure elevation in patients on maintenance dialysis.

Animals↗
PubMed1992

Adult T-cell leukemia developing during immunosuppressive treatment in a renal transplant recipient.

We report a case of a 32-year-old male, an asymptomatic carrier of human T-cell leukemia virus type 1 (HTLV-1), who underwent a renal transplantation and developed adult T-cell leukemia (ATL) during the course of posttransplant immunosuppressive treatment. He was treated with combination chemotherapies consisting of cyclophosphamide, vincristine, doxorubicin, prednisolone, cisplatin, cytosine arabinoside, etoposide, and methyl-prednisolone, without any improvement. Bestrabucil (KM2210), a conjugate of chlorambucil and estradiol, was administered as an alternative therapy; this therapy successfully suppressed his leukemic cell growth, and partial remission was achieved. Posttransplant immunosuppressive therapy with prednisolone, mizoribine, and cyclosporin A might have been the predominant cause of the transition from an asymptomatic HTLV-1 infection to overt ATL. A careful approach is required with HTLV-1 asymptomatic carriers who need organ transplantation followed by immunosuppressive treatment.

Adult↗