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Biomedical subjects

M Tashiro

Publications and source records attributed to M Tashiro.

At least 127 records · Page 7Linked to original sources
PubMed1994

[Simultaneous bilateral testicular tumors: a case report].

We report a case of bilateral simultaneously-occurring testicular tumors. A 43-year-old man was admitted to our clinic with a complaint of right inguinal pain in May 1992. Under the diagnosis of bilateral testicular neoplasms, bilateral high orchiectomy was performed. Histological examination revealed typical seminoma of bilateral testes. The patient was diagnosed with stage IIIO seminoma, and he was treated with combination chemotherapy (PVB). No evidence of disease has been seen after chemotherapy.

Adult↗
PubMed1993

An improved strategy for determining resonance assignments for isotopically enriched proteins and its application to an engineered domain of staphylococcal protein A.

Sequence-specific resonance assignments provide the basis for interpreting multidimensional NMR spectra and for determining 3D structures of proteins from these data. We have developed an improved strategy for determining these sequence-specific NMR assignments in small proteins and applied this method in determining proton and nitrogen resonance assignments for an 8.2-kDa engineered domain (the Z-domain) of the cell wall protein A of Staphylococcus aureus. First, HCCNH-TOCSY [Lyons, B. A. & Montelione, G.T. (1993) J. Magn. Reson. 101B, 206] data were used together with 2D 2QF-COSY, TOCSY, and 15N-HSQC data to identify amino acid spin systems. Most asparagine and glutamine spin systems were also identified uniquely from these triple-resonance data. Next, complementary HCC(CO)-NH-TOCSY [Montelione, G. T., et al. (1992) J. Am. Chem. Soc. 114, 10975] data were used to identify sequential connections from the aliphatic H alpha, H beta, H gamma, H delta, and H epsilon resonances of residue i to the amide and nitrogen resonances of residue i + 1. By combined analysis of HCCNH-TOCSY and HCC(CO)NH-TOCSY spectra we have determined most of the proton and nitrogen resonance assignments for the Z-domain. This represents the first example of the use of this triple-resonance technique to determine extensive resonance assignments in a small protein.

Amino Acid Sequence↗
PubMed1993

Pulmonary surfactant is a potential endogenous inhibitor of proteolytic activation of Sendai virus and influenza A virus.

The pathogenicities of influenza viruses and paramyxoviruses have been proposed to be primarily determined by a host cell protease(s) that activates viral infectivity by proteolytic cleavage of the envelope glycoproteins. We recently isolated a trypsin-type endoprotease, named tryptase Clara, from rat bronchial and bronchiolar epithelial Clara cells, which is secreted into the airway lumen and activates Sendai virus and influenza A virus proteolytically. We report here that surfactant in the bronchial fluid inhibited tryptase Clara specifically, having a Ki value of 0.13 microM, and inhibited the proteolytic activations by tryptase Clara in vitro and in organ cultures of rat lung. Intranasal infection of rats with Sendai virus was shown to stimulate secretion of tryptase Clara without changing the amount of surfactant in the bronchial lumen, resulting in a preferable condition for proteolytic viral activation and multiplication.

Amino Acid Sequence↗
PubMed1993

Binding of amino acid side chains to preformed cavities: interaction of serine proteinases with turkey ovomucoid third domains with coded and noncoded P1 residues.

In the association of serine proteinases with their cognate substrates and inhibitors an important interaction is the fitting of the P1 side chain of the substrate or inhibitor into a preformed cavity of the enzyme called the S1 pocket. In turkey ovomucoid third domain, which is a canonical protein proteinase inhibitor, the P1 residue is Leu18. Here we report the values of equilibrium constants, Ka, for turkey ovomucoid third domain and 13 additional Leu18X variants with six serine proteinases: bovine alpha chymotrypsin A, porcine pancreatic elastase, subtilisin Carlsberg, Streptomyces griseus proteinases A and B, and human leukocyte elastase. Eight of the Xs are coded amino acids: Ala, Ser, Val, Met, Gln, Glu, Lys, and Phe, and five are noncoded: Abu, Ape, Ahx, Ahp, and Hse. They were chosen to simplify the interamino acid comparisons. In the homologous series of straight-chain side chains Ala, Abu, Ape, Ahx, Ahp, free energy of binding decreases monotonically with the side-chain length for chymotrypsin with large binding pocket, but even for this enzyme shows curvature. For the two S. griseus enzymes a minimum appears to be reached at Ahp. A minimum is clearly evident for the two elastases, where increasing the side-chain length from Ahx to Ahp greatly weakens binding, but much more so for the apparently more rigid pancreatic enzyme than for the more flexible leukocyte enzyme. beta-Branching (Ape/Val) is very deleterious for five of the six enzymes; it is only slightly deleterious for the more flexible human leukocyte elastase. The effect of gamma-branching (Ahx/Leu), of introduction of heteroatoms (Abu/Ser), (Ape/Hse), and (Ahx/Met), and of introduction of charge (Gln/Glu) and (Ahp/Lys) are tabulated and discussed. An important component of the free energy of interaction is the distortion of the binding pocket by bulky or branched side chains. Most of the variants studied were obtained by enzymatic semisynthesis. X18 variants of the 6-18 peptide GlyNH2 were synthesized and combined with natural reduced peptide 19-56. Disulfide bridges were formed. The GlyNH2 was removed and the reactive-site peptide bond X18-Glu19 was synthesized by complex formation with proteinase K. The resultant complexes were dissociated by sudden pH drop. This kinetically controlled dissociation afforded virgin, reactive-site-intact inhibitor variants.

Amino Acid Sequence↗
PubMed1993

Antibody against the carboxyl terminus of the F2 subunit of Sendai virus fusion glycoprotein inhibits proteolytic activation.

Rabbit antibody, F2C12, was prepared against a synthetic peptide of 13 amino acids corresponding to the C-terminus of the F2 subunit of Sendai virus F protein. F2C12 was shown to bind specifically to the F2 subunit, irrespective of proteolytic cleavage of the F protein. F2C12 did not affect the infectivity, hemolytic, and cell fusion activities of activated virus, but F2C12 did inhibit proteolytic cleavage of the precursor F0 to subunits, F1 and F2, by trypsin, factor Xa from chick embryos and Tryptase Clara from rat lungs. When F2C12 was added to the chorioallantoic cavity of chick embryos, cleavage activation of Sendai virus was inhibited. Intranasal administration of F2C12 to Sendai virus-infected rats suppressed activation and multiplication of progeny virus in the lungs. These results indicate that proteolytic cleavage of the F protein, with a single arginine residue at the cleavage site, occurs extracellularly in the allantoic cavity of chick embryos and in the bronchial lumen of rats.

Allantois↗
PubMed1993

Persistence of viral genes in a variant of MDBK cell after productive replication of a mutant of influenza virus A/WSN.

The MDBK-R cell line is a variant of the MDBK cell line, which was derived by three consecutive high multiplicity superinfections of MDBK cells with AWBY-140 virus, a mutant of influenza virus A/WSN (H 1N 1). MDBK-R cells are permissive for productive replication of AWBY-140, but resist lysis by the virus and grew normally without producing infectious virus after replication of the mutant occurred there. By polymerase chain reaction (PCR), we demonstrated nucleotide sequences specific to all the 8 genes of AWBY-140 in MDBK-R cells which had been infected with the mutant at a high multiplicity and subsequently received 25 passages. This suggests that the genes of influenza virus mutant persisted in the dividing host cells for a long time after productive infection, when none of the cells was producing virus. We were also able to amplify the M gene related sequence of the mutant from both poly(A)+ and poly(A)- fractions of the RNA extracted from the cells at 27th passage level by PCR, which suggests that the persisting genes were replicated and transcribed, but we failed to demonstrate any viral protein in the cells by Western blotting.

Base Sequence↗
PubMed1993

Extrarenal Wilms' tumour.

Extrarenal Wilms' tumour is rare and its imaging has received scant mention in the literature. We describe a 2-year-old boy with a firm mass in the right flank. CT, MRI and ultrasonography showed an inhomogeneous solid mass located in the retroperitoneum, which was separate from the right kidney. Angiography showed an enlarged right gonadal artery and irregularly tortuous vessels in the tumour similar to intrarenal Wilms' tumour ("spider leg" or "creeping vine" appearance). Histopathological examination confirmed an extrarenal Wilms' tumour.

Child, Preschool↗
PubMed1993

T-cell receptor gene rearrangement in cells infiltrating skin eruptions specific to adult T-cell leukemia.

We examined T-cell receptor gene rearrangement in skin lesions and peripheral blood from 6 patients with adult T-cell leukemia (ATL) using the Southern blot method and a c beta 1 probe. A rearrangement signal common to skin lesions of all 6 patients was observed. One patient (Case 4) exhibited another rearrangement signal in the skin lesion and an identical signal was detected in the peripheral blood. This is the first report describing a specific pattern of T-cell receptor gene rearrangement in ATL. The signal obtained is assumed to represent receptors of T cells involved in surveillance of HTLV-I infected T cells.

Aged↗
PubMed1993

Serum manganese superoxide dismutase (MnSOD) and histological virulence of ovarian cancer.

The serum level of a scavenging enzyme, manganese superoxide dismutase (MnSOD), was examined in 78 patients with ovarian cancer. Tumors included 27 stage I, 6 stage II, 37 stage III and 8 stage IV diseases. They were classified as 43 serous, 18 mucinous, 10 clear cell and 7 endometrioid neoplasms, and grouped into 25 grade I, 27 grade II and 26 grade III cancers. Factors affecting the MnSOD level were estimated by analysis of variance and Bonferroni t-test. From these, both the stage and histology were less-effectively affected by the level, while the histological grade was estimated as effective with p < 0.05. The MnSOD value increased significantly in accordance with the escalation of the tumor grade with p = 0.02 for grade I vs II, 0.005 for II vs III, and 0.0001 for I vs III respectively. MnSOD determination may be unique as a predictor of the histological virulence of ovarian carcinoma.

Adenocarcinoma↗
PubMed1993

Possible involvement of microtubule disruption in bipolar budding of a Sendai virus mutant, F1-R, in epithelial MDCK cells.

Envelope glycoproteins F and HN of wild-type Sendai virus are transported to the apical plasma membrane domain of polarized epithelial MDCK cells, where budding of progeny virus occurs. On the other hand, a pantropic mutant, F1-R, buds bipolarly at both the apical and basolateral domains, and the viral glycoproteins have also been shown to be transported to both of these domains (M. Tashiro, M. Yamakawa, K. Tobita, H.-D. Klenk, R. Rott, and J.T. Seto, J. Virol. 64:4672-4677, 1990). MDCK cells were infected with wild-type virus and treated with the microtubule-depolymerizing drugs colchicine and nocodazole. Budding of the virus and surface expression of the glycoproteins were found to occur in a nonpolarized fashion similar to that found in cells infected with F1-R. In uninfected cells, the drugs were shown to interfere with apical transport of a secretory cellular glycoprotein, gp80, and basolateral uptake of [35S]methionine as well as to disrupt microtubule structure, indicating that cellular polarity of MDCK cells depends on the presence of intact microtubules. Infection by the F1-R mutant partially affected the transport of gp80, uptake of [35S]methionine, and the microtubule network, whereas wild-type virus had a marginal effect. These results suggest that apical transport of the glycoproteins of wild-type Sendai virus in MDCK cells depends on intact microtubules and that bipolar budding by F1-R is possibly due, at least in part, to the disruption of microtubules. Nucleotide sequence analyses of the viral genes suggest that the mutated M protein of F1-R might be involved in the alteration of microtubules.

Animals↗
PubMed1993

A case of epidermolysis bullosa hereditaria--dominant dystrophic type of Cockayne and Touraine.

We report a patient with the Cockayne and Touraine type epidermolysis bullosa dystrophica domains. A 6-year-old Japanese female developed blisters and erosions on the extremities 3 months after birth. Immunohistology showed a linear binding pattern of the monoclonal antibody against type VII collagen (LH:2) on the epidermal basement membrane. By means of electron microscopy and morphometric analysis, it became apparent that the anchoring fibrils were rudimentary in structure and reduced in number.

Basement Membrane↗
PubMed1993

The effects of tyramine on salivary flow rate and protein secretion by rat submandibular glands.

The effects of different doses of p-tyramine injected i.v. and i.p. on salivary flow rates and proteins secreted by the submandibular glands of rats were studied with and without various types of autonomic blockers and two enzyme inhibitors. The salivary flow rates and the amounts of protein secreted progressively increased with increasing doses injected both i.v. and i.p., whereas they were dramatically reduced with all autonomic blockers except the lowest doses of beta-blockers, atropine, and yohimbine. Salivation in response to p-tyramine injected i.v. and i.p. was completely abolished by simultaneous injections of both prazosin and propranolol. The concentration of protein was not dose-dependent and was not reduced by yohimbine and phenoxybenzamine at almost all doses used. However, prazosin significantly increased the protein concentration. Protease activities were dose-dependent but were significantly reduced with alpha-blockers other than yohimbine, and with most beta-blockers. The proteins secreted in response to p-tyramine at all doses injected i.v. and i.p. were of the alpha-type except with the lowest dose injected i.p. However, the alpha-type was completely replaced by the beta-type in the presence of all alpha-blockers except yohimbine, but not with beta-blockers, atropine, or two enzyme inhibitors. Pargyline, a monoamine-oxidase inhibitor, but not disulfiram, a dopamine-beta-hydroxylase inhibitor, affected all parameters except the type of protein. Thus, p-tyramine may activate both the alpha 1- and beta 1-adrenoceptors in the submandibular glands of rats directly or indirectly.

Adrenergic alpha-Antagonists↗
PubMed1993

The effects of p-octopamine on salivary flow rates and protein secretion by rat submandibular glands.

The effects of p-octopamine injected i.v. and i.p on salivary flow rates and proteins secreted by the submandibular glands of rats were studied with and without various types of autonomic blockers at different doses, and with two enzyme inhibitors. The salivary flow rates and the amounts of protein secreted progressively increased with increasing doses injected both i.v. and i.p., whereas they were dramatically reduced with almost all autonomic blockers and disulfiram, a dopamine-beta-hydroxylase inhibitor. Salivation was completely abolished in response to p-octopamine in combination with metoprolol or phenoxybenzamine at high doses, and simultaneous injections of prazosin and propranolol. The concentration of protein in submandibular saliva in response to p-octopamine injected i.v. and i.p. was not dose-dependent and significantly increased with all of the alpha-blockers except yohimbine, and with atropine and disulfiram. The protease activity was dose-dependent but was reduced significantly with alpha-blockers except yohimbine and with two enzyme inhibitors. The alpha-type of protein was secreted in response to p-octopamine injected i.v. and i.p. at all doses except with the lowest dose i.p., which caused the beta-type to be secreted. The alpha-type was completely replaced by the beta-type with all alpha-blockers at all doses, except with yohimbine, but no change was observed with various types of beta-blockers, yohimbine, atropine, and two enzyme inhibitors. Thus, p-octopamine could stimulate both the alpha- and beta-adrenoceptors in the submandibular glands of rats.

Adrenergic alpha-Antagonists↗
PubMed1993

Primary embryonal carcinoma of the retroperitoneum.

A 32-year-old man with primary embryonal carcinoma of the retroperitoneum, a very rare condition, is reported. The disease took an acute course with rapid enlargement of cervical and inguinal lymph nodes, and high serum alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) values were observed. His testes were, however, intact. Remarkable tumor regression was achieved by systemic combination chemotherapy with cisplatin, vinblastine, and bleomycin (PVB therapy). This chemotherapy is beneficial even in advanced cases. In the two years since therapy, no recurrence has been observed.

Adult↗
PubMed1993

Progressive external ophthalmoplegia and myositis.

We reported a senile male patient with progressive external ophthalmoplegia (PEO) and myositis. The ophthalmoplegia was severe, but other neuromuscular features were nearly normal. Muscle enzymes in serum were moderately elevated. Autoimmune, endocrinological or malignant diseases were not observed during the previous 4 years. Pathology of non-weak limb muscles biopsied twice was consistent with active inflammatory myopathy. The ragged-red or cytochrome c oxidase-negative fibers, which are a hallmark of mitochondrial myopathy with PEO, were not increased in comparison with age-matched control muscles. Analysis of mitochondrial DNA in muscle by the Southern blot method did not reveal any deletions. It was concluded that the inflammatory myopathy, myositis clinically localized at the ocular muscles, is an important and distinct disorder in PEO.

Aged↗
PubMed1993

[Transdermal application of 10% lidocaine-gel for management of pain associated with herpes zoster].

We have developed transdermally applicable 10% lidocaine aqueous gel containing an absorption promoter and applied it for 15 patients suffering from severe pain in acute or subacute phase of herpes zoster. The patients, consisting of 7 males and 8 females with a mean age 58.5 +/- 13.0 (SD) yrs, had skin eruptions of herpes zoster for the past 2 months. Lidocaine-gel was applied locally to the diseased skin with or without an occlusive dressing. In 14 of the 15 patients (93%), a remarkable reduction of pain (below 10% of pretreatment level) was obtained after 9.9 +/- 5.6 (SD) times of lidocaine-gel treatments. There was no adverse systemic reactions or local skin damages. None of them developed post-herpetic neuralgia. The lidocaine-gel treatment appears to be very useful for reduction of pain associated with acute or subacute phase of herpes zoster.

Administration, Cutaneous↗
PubMed1992

Isolation and characterization of a novel trypsin-like protease found in rat bronchiolar epithelial Clara cells. A possible activator of the viral fusion glycoprotein.

A novel trypsin-like protease associated with rat bronchiolar epithelial Clara cells, named Tryptase Clara, was purified to homogeneity from rat lung by a series of standard chromatographic procedures. The enzyme has apparent molecular masses of 180 +/- 16 kDa on gel filtration and 30 +/- 1.5 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. Its isoelectric point is pH 4.75. Studies with model peptide substrates showed that the enzyme preferentially recognizes a single arginine cleavage site, cleaving Boc-Gln-Ala-Arg-4-methylcoumaryl-7-amide most efficiently and having a pH optimum of 7.5 with this substrate. The enzyme is strongly inhibited by aprotinin, diisopropylfluorophosphate, antipain, leupeptin, and Kunitz-type soybean trypsin inhibitor, but inhibited only slightly by Bowman-Birk soybean trypsin inhibitor, benzamidine, and alpha 1-antitrypsin. Immunohistochemical studies indicated that the enzyme is located exclusively in the bronchiolar epithelial Clara cells and colocalized with surfactant. An immunoreactive protein with a molecular mass of 28.5 kDa was also detected in airway secretions by Western blotting analyses, suggesting that the 30-kDa protease in Clara cells is processed before or after its secretion. Proteolytic cleavage of the hemagglutinin of influenza virus is a prerequisite for the virus to become infectious. Tryptase Clara was shown to cleave the hemagglutinin and activate infectivity of influenza A virus in a dose-dependent way. These results suggest that the enzyme is a possible activator of inactive viral fusion glycoprotein in the respiratory tract and thus responsible for pneumopathogenicity of the virus.

Amino Acid Sequence↗