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H Tashiro

Publications and source records attributed to H Tashiro.

At least 109 records · Page 6Linked to original sources
PubMed1996

Reduced microtubule-nucleation activity of tau after dephosphorylation.

Based on video-enhanced differential interference contrast (DIC) microscopy, we developed a small-scale method which is capable of measuring both the lengths and the number densities of microtubules (MTs) assembled in vitro. With this method, effect of dephosphorylation on the activity of bovine brain tau protein to promote the assembly of tubulin at physiological concentration (15 microM) was quantitatively analyzed. The MT number density was selectively reduced when tau isolated directly in the presence of phosphatase inhibitors (N-tau) was dephosphorylated in vitro (DP-tau), without significant changes in the mean MT length or the binding affinity toward preformed MTs. Tau obtained from brain MTs (MT-tau) also exhibited lower nucleation activity in spite of its high MT-binding affinity. The results indicate that nucleation, elongation and MT-binding are distinct aspects of tau function which are differentially affected by the phosphorylation state of tau.

Animals↗
PubMed1996

Sequencing of a 23 kb fragment from Saccharomyces cerevisiae chromosome VI.

Plasmid clone gapB and lambda phage clone 4682, which contain fragments of Saccharomyces cerevisiae chromosome VI, were analysed. A 23 kb sequence was determined and ten open reading frames (ORFs) were revealed. Among them, five ORFs were identical to five yeast genes (SEC4, MSH4, SPB4, DEG1 and NIC96), two were identical to transposable elements (TYA and TYB), one (gapBorfF003) was highly homologous to a yeast expressed sequence tag, and another (4682orfF002) was predicted to be a nuclear protein. Sequence data have been submitted to DDBJ/EMBL/GenBank data library under Accession Number D44604 (clone gapB) and D44600 (clone 4682), respectively.

Amino Acid Sequence↗
PubMed1996

Short arm of chromosome 1 aberration recurrently found in pigmented villonodular synovitis.

Pigmented villonodular synovitis (PVNS) is a relatively uncommon benign lesion that is characterized by diffuse synovial proliferation, mainly occurring in knee joints. Cytogenetic reports about this lesion are few and they describe the presence of numerical and structural chromosome aberrations. We obtained PVNS tissue from the left knee joint of a 53-year-old female, and performed cytogenetic analysis. Fluorescence in situ hybridization (FISH) was also performed by using the formalin fixed, paraffin embedded PVNS tissue. Two seemingly unrelated clones were found: the first clone had structural abnormalities of chromosome 1, 3, and 18, and the second one had trisomy 7 as a sole numerical abnormality. FISH using a chromosome 7 specific alpha-satellite DNA probe revealed that interphase nuclei possessed two or three signals. We describe the clonal aberrations found in a case of PVNS. The deleted lesion of the chromosome 1 (1p10-1p31.3) includes the locus of coagulation factor III gene (1p22-p21), and the coagulation factor V (1q21-q25) locus includes another breakpoint that is 1q25. In addition, recurrent structural abnormalities at the short arm of chromosome 1 have been reported. These facts might play some role in the hemorrhagic tendency and histogenesis of these lesions.

Chromosome Aberrations↗
PubMed1996

Assessment of microchimerism in rat liver transplantation by polymerase chain reaction.

Mixed chimerism has been demonstrated in organ transplant recipients surviving over a long period. However, little is known about the fate and movements of donor cells following liver transplantation. In this study, using rat male-to-female liver transplantation, we assessed microchimerism by semiquantitative polymerase chain reaction (PCR). A PCR specific for the Y-chromosome (sex-determining region Y [Sry]) allowed the distinction of small amounts of male cells in a large excess of female cells. Nonimmunosuppressed Lewis recipients of Lewis liver grafts survived >60 days, and donor cells were detected in peripheral blood up to day 60 in four of six recipients. All immunosuppressed Lewis recipients survived for 60 days, and the donor cells were detected up to day 60. Semiquantitative PCR demonstrated that in immunosuppressed Lewis recipients surviving >60 days with no acute rejection episode, the donor-to-recipient cell ratio remained >1:1,000. In nonimmunosuppressed Lewis recipients of ACI liver allografts, donor cells in peripheral blood decreased rapidly by day 7. In immunosuppressed Lewis recipients of ACI liver allografts, donor cells were detected for longer periods, in proportion to the amount and duration of FK506 (Fujisawa Pharmaceutical Co., Osaka, Japan) administered. However, in recipients with deteriorating function due to ongoing rejection, small amounts (0.01 percent) of donor cells were detected. Our results indicate that the Sry-specific PCR is useful for assessing microchimerism following rat liver transplantation, and demonstrate correlation between microchimerism and graft outcome; high-level microchimerism (>O.l percent) correlated well with graft acceptance, whereas low-level microchimerism (<O.01 percent) did not.

Animals↗
PubMed1996

Cephalometric comparison of craniofacial morphology between primary bone grafted and nongrafted complete unilateral cleft lip and palate adults.

The effect of primary bone grafts on craniofacial growth was evaluated in adult patients with complete unilateral cleft lip and palate (UCLP). The subjects were 18 UCLP patients with primary bone grafts and a control group of 36 UCLP patients without bone grafts. The former received primary transplantation of autogenous rib bone simultaneously with primary cheiloplasty by the same surgeon between 1963 and 1969. Frontal and lateral cephalograms taken after 16 years of age were traced. Skeletal landmarks were identified on them, and their x,y-coordinates were digitized. The effects of gender and/or primary bone graft on the craniofacial morphology were tested by ANOVA using 21 angles, 8 breadths, 13 distances, and 2 ratios. Nasal cavity breadth was wider in the primary bone grafted group. However, the anterior maxilla in that group was more upward and retruded than that in the nongrafted group. The primary bone grafted group was divided into two subgroups based on the overjet of the incisors: group N = normal overjet; group C = anterior cross-bite. There was no difference in the maxilla between groups N and C. However, the mandible in group C was more anterior and superior than in group N. In conclusion, primary bone graft may impede maxillary horizontal and vertical growth to a certain degree, and severe anterior cross-bite in primary bone grafted subjects may be brought about by mandibular closure.

Adult↗
PubMed1996

[Chemo-endocrine therapy including mitomycin C and medroxyprogesterone acetate in doxorubicin-refractory advanced breast cancer].

In the management of doxorubicin (ADR)-refractory advanced breast cancer, combination chemotherapies including mitomycin C (MMC) have been widely acknowledged to have definitive therapeutic effects. A randomized comparative study was performed estimating the efficacy and toxicity of MMV chemotherapy (MMC+methotrexate+vincristine), MMVM (MMV+medroxyprogesterone acetate (MPA), and MMVP (MMV+predo-nisolone (P). A total of 108 patients with advanced breast cancer resistant to ADR or relapsed after response were randomized, and 102 were evaluable. Response rates of 9.5% (2/21) in MMV, 37.5% (15/40) in MMVM, and 29.2% (12/41) in MMVP were obtained; with a significant difference between MMV and MMVM (p = 0.021). The time to progression of patients treated with MMVM and MMVP was shown to be longer than MMV patients. Thrombocytopenia was less appeared by adding MPA, making the dose escalation of MMV agents. It was concluded also from reviewing the references that MMVM is an effective 2nd-line therapy of advanced breast cancer after ADR treatment.

Aged↗
PubMed1996

HLA-DR8 subtyping by polymerase chain reaction (PCR)-DNA conformation polymorphism (DCP) analysis: a simple and practical genotyping method.

Two hundred Japanese panels were serologically typed for human leukocyte antigen (HLA) - DR to assign 65 HLA-DR8 haplotypes, which were then subdivided into two genotypes, i.e., DRB1*0802 and DRB1*0803, by a polymerase chain reaction (PCR)--based, simple, and practical method. The panels possessing DR8 specificity were firstly subjected to PCR with a couple of primers specifically to amplify their DR52 associated group--DRB1 genes. PCR products were then denatured in the presence of formamide, electrophoresed in a non-denaturing polyacrylamide gel, and visualized by silver staining. The same DRB1 products of these samples were also mixed with the DRB1*1302, and simultaneously analyzed by the same procedure. Electrophoretic mobilities of the samples were compared with those of the typing standards to genotype their DR8--DRB1 alleles by using the characteristic polymorphism in the single-stranded DNAs and the heteroduplexes. This method, designated PCR--DNA conformation polymorphism (DCP) analysis, allowed for genotyping of the DR8-DRB1 alleles without using sequence-specific oligonucleotide probes (SSOP) or restriction endonucleases. The entire process after PCR was completed within a few hours. The tested panels were also genotyped for DRB1 gene by the PCR-SSOP method for comparison with results obtained by the PCR-DCP method. Satisfactory coincidence was achieved and it represented how accurately the new system genotyped DRB1*0802 and DRB1*0803. PCR-DCP analysis was thus shown to be practical and useful for subtyping of serologically defined DR8 specificities.

Base Sequence↗
PubMed1995

Nucleotide sequence surrounding the locus marker D21S246 on human chromosome 21.

Most of the human Not I linking clones identified to date are considered to be derived from CpG islands because of the recognition sequence of this enzyme, and CpG islands have been reported to be located around the 5' regions of genes. As a pilot study, we determined the complete nucleotide sequence (41,924 bp) of a human cosmid clone (LL21NC02Q7A10) containing the marker D21S246 originating from a Not I linking clone. As a result of sequence analysis, we successfully mapped and revealed the genomic gene structure for KIAA0002 previously reported as a cDNA clone. This gene consists of 15 exons and was shown to exist at the D21S246 locus on human chromosome 21q21.3-q22.1. These results demonstrated that genomic marker-anchored DNA sequencing is a useful approach for the human genome project.

Base Sequence↗
PubMed1995

Buckling of a single microtubule by optical trapping forces: direct measurement of microtubule rigidity.

As major determinants of cell shape and polarity, microtubules are required to have suitable rigidity. However, our knowledge of the mechanical properties of microtubules is far from satisfactory. We report here a new method of measuring the flexural rigidity of a single microtubule by direct buckling using the optical trapping technique. Microtubule buckling was induced by applying a small longitudinal compressing force through an optically trapped microsphere that was firmly attached to the microtubule. Three ways of estimating the flexural rigidity of a continuous slender rod, one from the observed critical load of buckling and two from deflected lengths and angles of bending, yielded values which agreed well when applied to the analysis of buckling microtubules. Unexpectedly, we found that the rigidity was not constant as expected but was dependent on microtubule length. This length dependency explains the discrepancies among reported values of microtubule flexural rigidity measured by different methods. Comparing microtubules of identical lengths, microtubules assembled with brain-derived associated proteins (4 x 10(-23) Nm2 at around 10 microns in length) were four times more rigid than those assembled from purified tubulin and stabilized with taxol (1 x 10(-23) Nm2).

Animals↗
PubMed1995

Auxiliary heterotopic partial liver transplantation in pigs with acute liver failure.

Fulminant hepatic failure is usually fatal without liver transplantation; however, orthotopic liver transportation is often difficult to perform due to the high risk of coagulopathy and the development of multiple organ failure. Auxiliary heterotopic partial liver transplantation (APLT), However, has the potential to provide an effective hepatic support system considering that the host liver is left in situ and the surgical procedure is less invasive. In this report, we describe the beneficial effects of performing 60% APLT on the hepatic function and survival of pigs with acute hepatic failure induced by hepatic artery ligation. The pigs were divided into a control group of nine animals (group 1) that had portal vein and hepatic artery ligation with a side-to-side portacaval shunt, and an APLT group of seven animals (group 2) that had portal vein and hepatic artery ligation with APLT. The two left lateral lobes of the donor liver were resected, reducing the liver weight to about 60%, and the graft was placed in the right subhepatic space. No deaths occurred intraoperatively. In group 1, eight pigs died of massive liver necrosis within 48 h and one died between 48 and 72 h (median survival 23 h). In group 2, two pigs died within 72 h due to preservation or anesthetic problems, but five survived for more than 3 days (median survival 13.4 days), with a significant difference between the two groups (P < 0.05). One animal was killed 30 days after APLT and excellent graft function was demonstrated by the synthesis of clotting factors, ammonia detoxification, and glucohomeostasis. Moreover, evidence of hepatic regeneration was found in the transplanted livers.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Long term survival and the prognostic factors of advanced breast cancer patients treated with adreno-oophorectomy.

Longer survival data are necessary to elucidate the prognostic factors for survival in advanced breast cancer patients. Univariate and multivariate analyses were performed in 159 patients treated with adreno-oophorectomy alone as the first-line treatment for advanced or recurrent breast cancer, between 1972 and 1983. Nine clinical factors included age, menopausal status, estrogen (ER)- and progesterone receptors (PgR) in recurrent tumors, disease-free interval (DFI), number of metastatic organs, performance status, and adjuvant therapy performed. Response was evaluated according to the UICC criteria. A 31% (50/159) response with 16 CR, 34 PR, 48 NC, and 61 PD was obtained. The logistic regression model of the factors showed that ER was the single affecting factor for the response. According to the Cox proportional hazard model, ER and the dominant site of metastasis were indicated to be significant for survival. According to the landmark method, the response significantly correlated to survival. Using the backward elimination procedure of the Cox proportional hazard model in the patient group defined by the landmark time of 3 months after therapy, the survival of the patients with advanced breast cancer was shown to be primarily influenced by the tumor response which was solely affected by ER status, and the dominant site, particularly the presence of liver metastasis, independently modified the survival length. These results may be useful in future studies of total estrogen blockade trials for breast cancer.

Adrenalectomy↗
PubMed1995

Active oxygen species in formation of acute gastric mucosal lesions induced by thermal injury in rats.

Active oxygen species generated by circulating leukocytes and released from the gastric mucosa were measured in the process of acute gastric mucosal lesion formation after thermal injury in rats. Alterations of luminol-dependent chemiluminescence activities generated by leukocytes obtained from the gastric vein and the inferior vena cava were approximately same. A decrease in chemiluminescence activity 15 min after thermal injury and a significant increase in chemiluminescence activity 5 hr after thermal injury were observed in leukocytes from both veins. From 15 min to 12 hr after thermal injury, luciferin-dependent chemiluminescence activities were significantly higher than that of the control group. Oral administration of rebamipide resulted in decreased mucosal lesion formation. Rebamipide, an antiulcer agent that protects the mucosa from damage in various animal models decreased chemiluminescence activities only released from the gastric mucosa but not from circulating leukocytes. These results suggest that two different pathways of active oxygen species formation may exist in the pathogenesis of acute gastric mucosal lesions after thermal injury.

Acute Disease↗
PubMed1995

Differential suppression of axoplasmic transport: effects of light irradiation to the growth cone of cultured dorsal root ganglion neurons.

1. Growth cones of cultured dorsal root ganglion neurons from mice were irradiated using a mercury lamp. 2. The flux of particles of fast retrograde axoplasmic transport decreased promptly after light irradiation without a change in velocity. 3. That of anterograde transport decreased as well, but with a significant latency. The decrease in anterograde flux was attributed to decreased velocity of particles. 4. Video-enhanced contrast microscopy of growth cones revealed transient swelling of growth cones and transient stagnation of particles in growth cones. 5. The longer the neurite, the larger the latency of the change of the anterograde transport; peripheral information was calculated to be conveyed to the cell body at a speed of 6 microns/min. 6. The mechanism of this information conveyance and the export of materials from the cell body are discussed.

Animals↗