Search PubMed⌕ Search

Biomedical subjects

T Yano

Publications and source records attributed to T Yano.

At least 397 records · Page 22Linked to original sources
PubMed1995

[Eight cases of infection caused by the Streptococcus milleri group--significance of serum antibody titer and a comparative investigation of the backgrounds and factors of infections caused by Streptococcus milleri and Streptococcus pneumoniae].

Eight cases of infection caused by Streptococcus milleri were studied clinically, and a comparative study was made of the backgrounds and factors influencing the development of infectious diseases caused by Streptococcus milleri and Streptococcus pneumoniae. The patients (six males and two females) with infectious diseases caused by Streptococcus milleri ranged in age from 21 to 81 years old with an average age of 62.0 years. The infectious diseases encountered among the patients were pyothorax in three patients, and in one patient each pyothorax and lung abscess, pleurisy, a secondary infection of pulmonary emphysema, skin infection related to a tracheostomy, a subdural abscess and a brain abscess, respectively. Six out of the eight cases had infections which formed pus. An underlying disease existed in seven cases, and, in five of these seven cases, it influenced the general condition of these patients. Six serum antibody titers for the S. milleri groups were examined in the First Department of Internal Medicine, University of the Ryukyus. Three cases for S. anginosus, two cases for S. intermedius, and one case for S. constellatus showed high titers of X1024 or X2048. Therefore, the examination of the serum antibody titer seems useful for the diagnosis of infections caused by the S. milleri group. We also carried out a comparative investigation of the backgrounds and factors of infectious diseases caused by S. milleri and S. pneumoniae. There are more underlying diseases in infections caused by S. milleri than in those caused by S. pneumoniae. There were more smokers among the patients with infections caused by S. milleri than among those with S. pneumonia infections.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Characterization of DNA synthesis and DNA-dependent ATPase activity at a restrictive temperature in temperature-sensitive tsFT848 cells with thermolabile DNA helicase B.

A temperature-sensitive mutant defective in DNA replication, tsFT848, was isolated from the mouse mammary carcinoma cell line FM3A. In mutant cells, the DNA-dependent ATPase activity of DNA helicase B, which is a major DNA-dependent ATPase in wild-type cells, decreased at the nonpermissive temperature of 39 degrees C. DNA synthesis in tsFT848 cells at the nonpermissive temperature was analyzed in detail. DNA synthesis measured by incorporation of [3H]thymidine decreased to about 50% and less than 10% of the initial level at 8 and 12 h, respectively. The decrease in the level of thymidine incorporation correlated with a decrease in the number of silver grains in individual nuclei but not with the number of cells with labeled nuclei. DNA fiber autoradiography revealed that the DNA chain elongation rate did not decrease even after an incubation for 10 h at 39 degrees C, suggesting that initiation of DNA replication at the origin of replicons is impaired in the mutant cells. The decrease in DNA-synthesizing ability coincided with a decrease in the level of the DNA-dependent ATPase activity of DNA helicase B. Partially purified DNA helicase B from tsFT848 cells was more heat sensitive than that from wild-type cells. Inactivation of DNA-dependent ATPase activity of DNA helicase B from mutant cells was considerably reduced by adding DNA to the medium used for preincubation, indicating that the DNA helicase of mutant cells is stabilized by binding to DNA.

Animals↗
PubMed1995

A link between increased transforming activity of lymphoma-derived MYC mutant alleles, their defective regulation by p107, and altered phosphorylation of the c-Myc transactivation domain.

The c-Myc protein is a transcription factor with an N-terminal transcriptional regulatory domain and C-terminal oligomerization and DNA-binding motifs. Previous studies have demonstrated that p107, a protein related to the retinoblastoma protein, binds to the c-Myc transcriptional activation domain and suppresses its activity. We sought to characterize the transforming activity and transcriptional properties of lymphoma-derived mutant MYC alleles. Alleles encoding c-Myc proteins with missense mutations in the transcriptional regulatory domain were more potent than wild-type c-Myc in transforming rodent fibroblasts. Although the mutant c-Myc proteins retained their binding to p107 in in vitro and in vivo assays, p107 failed to suppress their transcriptional activation activities. Many of the lymphoma-derived MYC alleles contain missense mutations that result in substitution for the threonine at codon 58 or affect sequences flanking this amino acid. We observed that in vivo phosphorylation of Thr-58 was absent in a lymphoma cell line with a mutant MYC allele containing a missense mutation flanking codon 58. Our in vitro studies suggest that phosphorylation of Thr-58 in wild-type c-Myc was dependent on cyclin A and required prior phosphorylation of Ser-62 by a p107-cyclin A-CDK complex. In contrast, Thr-58 remained unphosphorylated in two representative mutant c-Myc transactivation domains in vitro. Our studies suggest that missense mutations in MYC may be selected for during lymphomagenesis, because the mutant MYC proteins have altered functional interactions with p107 protein complexes and fail to be phosphorylated at Thr-58.

Alleles↗
PubMed1995

Conversion of cathepsin E to enzymatic unstable form in gastric cancer cells.

A new acid proteinase in human gastric cancer, named medium moving proteinase (Med.P), was found also in a gastric cancer transplanted into nude mouse. However, Med.P disappeared when the samples prepared from gastric cancer tissues were left for over 4 weeks at -80 degrees C, whereas the activity of cathepsin E (CE) increased. When these samples were reduced by dithiothreitol (DTT), Med.P appeared again and the CE activity decreased. These phenomena, revealed by electrophoretic analyses, indicated that Med.P is a monomeric form of CE (mono-CE). At weakly alkaline pH and after heating, mono-CE appeared to be more unstable than CE. These results indicated that CE assume an enzymatically unstable monomeric form in cancer cells.

Animals↗
PubMed1995

Synthesis of carboxymethylpullulan-peptide-doxorubicin conjugates and their properties.

The amino group of doxorubicin (DXR) was found to be bound to the carboxyl group of carboxymethylpullulan (CMPul) either directly or through tetrapeptide spacers, including Gly-Gly-Phe-Gly, Gly-Phe-Gly-Gly and Gly-Gly-Gly-Gly. These conjugates had DXR contents of 6.1-7.1%, with the degree of substitution of carboxymethyl groups being 0.6 per sugar moiety. These conjugates associate in phosphate-buffered saline (PBS) (pH 7.4), forming micelles with hydrophobic DXR inside and hydrophilic CMPul on the outside. The amounts of DXR released from the conjugates in the presence of rat liver lysosomal enzymes were determined by HPLC. The rate of the drug release differed among the conjugates tested. CMPul-DXR conjugate bound through Gly-Gly-Phe-Gly released 35% of its DXR over 24 h. On the other hand, CMPul-DXR conjugate without spacer released no free DXR. The antitumor effect of each conjugate in rats bearing Walker 256 was studied by monitoring the tumor weights after a single intravenous injection. Compared with DXR, CMPul-DXR conjugates bound through Gly-Gly-Phe-Gly and Gly-Phe-Gly-Gly spacers significantly suppressed the tumor growth, while CMPul-DXR conjugate bound through Gly-Gly-Gly-Gly showed less antitumor effect than DXR. CMPul-DXR conjugate bound through Gly-Gly-Gly-Gly showed less antitumor effect than DXR. CMPul-DXR conjugate without spacer showed no in vivo antitumor effect even at a dose equivalent to as much as 20 mg/kg of DXR.

Amino Acid Sequence↗
PubMed1995

[Effects of ethyl all-cis-5,8,11,14,17-icosapentaenoate on low density lipoprotein in rabbits].

The hypolipidemic effects of ethyl all-cis-5,8,11,14,17-icosapentaenoate (EPA-E) on cholesterol diet-fed rabbits were studied. EPA-E (300 mg/kg, p.o. x 4 weeks) decreased total cholesterols in the lipoprotein fractions of very low-density lipoprotein and intermediate lipoprotein+low-density lipoprotein (LDL), but not in high-density lipoprotein. Furthermore, the properties of LDL were investigated in rabbits given EPA-E (300 mg/kg, p.o. x 2 weeks). EPA-E had no influence on the lipid composition in LDL, and the cholesterol accumulation into macrophages was not increased by the incubation with EPA-E-treated LDL. However, the omega 3 polyunsaturated fatty acids contents of LDL were increased by the administration of EPA-E. EPA-E-treated LDL was also studied on the binding to the hepatic membranes. The binding of EPA-E-treated LDL to the hepatic membranes was higher than that of ordinary LDL. These results suggest that EPA-E causes a modification of LDL, such that EPA-E has an enhancing effect on the hepatic uptake of LDL. These effects may contribute to the hypolipidemic action of EPA-E.

Animals↗
PubMed1995

Ras amplification in BHK-21 cells produces a host cell line for further rapid establishment of recombinant protein hyper-producing cell lines.

To rapidly establish recombinant protein hyper-producing cell lines we introduced a reporter plasmid into BHK-21 cells that had been 'primed' by transfection and amplification of the ras oncogene. The reporter plasmid used carries the human interleukin-6 (hIL-6) gene which is under control of the human cytomegalovirus immediate early promoter. The primed BHK cell lines were shown to produce many stable hIL-6 hyper-producing cells achieving about 15 times higher productivity than the control BHK-21 cells.

Animals↗
PubMed1995

E1A and ras oncogenes synergistically enhance recombinant protein production under control of the cytomegalovirus promoter in BHK-21 cells.

The amplified ras oncogene greatly enhanced the production of recombinant human interleukin-6 (hIL-6) under control of the cytomegalovirus immediate early promoter (CMV promoter) in BHK-21 cells. When the adenovirus E1A oncogene was further transfected into the above mentioned ras-amplified hIL-6 hyperproducing BHK cells, the transfectants had about 10 times higher productivity than non-transfectants. However, the E1A gene alone did not enhance productivity. These results implicate a ras and E1A synergistic ability that acts to enhance hIL-6 production.

Adenoviridae↗
PubMed1995

Anterior pituitary function in patients with nonfunctioning pituitary adenoma: results of longitudinal follow-up.

Studies of anterior pituitary function in patients treated for nonfunctioning pituitary adenomas have been limited by their short duration. The purpose of the present study was to examine pituitary function longitudinally among three types of patients: those with complete tumor removal (group A); those with subtotal or partial adenomectomy (group B); and those in group B who underwent additional radiation therapy (group C). The subjects were 33 patients whose anterior pituitary function was evaluated by provocative tests such as insulin induced hypoglycemia, thyrotropin releasing hormone administration test and luteinizing hormone releasing hormone administration test. They underwent preoperative evaluation and postoperative reevaluations at 2 weeks, 3 months, 6 months and annually thereafter, for over 10 years. Anterior pituitary function was restored within a year after surgery, if at all. No additional function was restored after one year from treatment. In group A, no one developed impairment of anterior pituitary function after one year from surgery. In group B, however, new impairment was noted at intervals, due to tumor regrowth. In Group C, deficiencies developed after one year, irrespective of tumor regrowth. In conclusion, lifelong endocrinological follow-up is recommended for patients receiving postoperative irradiation, and for patients with potential for tumor regrowth. On the other hand, patients with total adenomectomy may be exempted from periodic endocrinological follow-up if they do not need postoperative hormonal replacement therapy.

Adenoma↗
PubMed1995

An event-related potential study of the effects of semantic deviations: an application of a method of sequential-part presentation.

The present study was designed to evaluate the effects of semantic deviations of picture stimuli by applying a method of sequential-part presentations. S1 stimuli were 10 pictures of animals which were divided into 7 x 7 portions and successively presented in random order. S2 stimuli were three types of pictures (A, the same as S1; B, semantically the same but physically different from S1; and C, both semantically and physically different from S1). Subjects were required to name S1 verbally after seeing S2. The largest N400 components of the event-related potential were elicited for Category C of S2, whereas large LPCs were elicited for Categories B and C. This suggests that a method of sequential-part presentations is effective for eliciting the N400 component of the event-related potential for picture stimuli.

Adult↗
PubMed1995

Clinicopathologic characteristics of stage I lung adenocarcinoma in women.

A total of 75 cases of surgically resected Stage I lung adenocarcinoma in women were analyzed. The patients were divided into three age groups: less than 50, between 50 and 70, and more than 70 years old. On the basis of the pathological T factor, 45 of 75 (60%) were T1 and 30 of 75 (40%) were T2 tumor. On the basis of pleural involvement, 47 of 75 (63%) cases revealed p0. On the basis of differentiation, all but two cases (97%) were well to moderately differentiated. On the basis of structure, papillary adenocarcinoma were 64 of 75 (85%). There was no difference among the three age groups in the pathological findings. Survival curves of each group indicated no statistically significant difference. We suggest that hormonal factors related to age do not affect the characteristics of lung cancer in women nor the survival of the patients.

Adenocarcinoma↗
PubMed1995

[A successful case of ischemic cardiomyopathy associated with left ventricular aneurysm and mitral regurgitation].

A 67-year-old female patient underwent a left ventricular aneurysmectomy and mitral valve replacement for ischemic cardiomyopathy. The replacement was done through left ventricle rather than left atrium. She had heart failure of NYHA class IV despite aggressive medical therapy. Preoperative examination revealed a left ventricular aneurysm and mitral regurgitation of grade II with markedly reduced ventricular function (LVEF 17%). Mitral valve replacement through left ventricle preserving chorda of the mitral valve is a promising method to eliminate regurgitation and shorten the cardiac ischemic time.

Aged↗
PubMed1995

Stimulating effect of excess iron feeding on spontaneous lung tumor promotion in mice.

This study was undertaken to estimate if dietary iron could stimulate factors which promote spontaneous lung tumorigenesis in A/J mice, by measuring biochemical parameters of oxidative stress on pulmonary nuclei, ornithine decarboxylase (ODC) and spermidine/spermine N1-acetyltransferase (SAT) activities as markers of tumor promotion. Feeding excessive iron (500%) to A/J mice for 28 weeks significantly elevated pulmonary DNA single strand break (DNA-SSB) as well as nuclear thiobarbituric acid reactive substances (TBARS) in connection with the increase of nuclear nonheme iron level. In contrast, nuclear alpha-tocopherol levels in the iron-loaded group significantly decreased as compared to that in the control group. Pulmonary ODC and SAT activities showed increasing tendency on feeding excess iron for 28 weeks. These results suggest that dietary iron stimulates spontaneous lung tumor promotion in A/J mice, partly due to the enhancement of oxidative damage to the pulmonary nuclei.

Acetyltransferases↗
PubMed1995

Results of a limited resection for compromised or poor-risk patients with clinical stage I non-small cell carcinoma of the lung.

BACKGROUND: Patients with stage I non-small cell carcinoma of the lung may be unable to undergo a standard curative resection, such as lobectomy, due to various medical reasons. Whether or not a limited resection is superior to radiotherapy in these patients, both in terms of long-term prognosis and treatment morbidity, is unknown. STUDY DESIGN: We retrospectively reviewed our results in treating compromised or poor-risk patients with clinical stage I non-small cell carcinoma of the lung who had received either a limited resection or radiotherapy. Seventeen patients underwent a limited resection (nine wedge resections and eight segmentectomies), while 18 patients received radiation therapy. RESULTS: The five-year survival rates for patients in the limited resection group and the radiation treatment group were 55.0 and 14.4 percent, respectively. A log-rank analysis showed a significant difference between the two groups (p = 0.004). Furthermore, the survival rate of the patients having a limited operation was significantly better than that of patients achieving either complete response or partial response from radiotherapy (18.8 percent at five years, p = 0.008). Recurrence at the surgical margin occurred in four patients in whom the tumor was greater than 2 cm in longest diameter. The incidence of severe treatment-related complications was not different between the limited operation group and the radiotherapy group (11.8 compared to 11.1 percent). CONCLUSIONS: The results indicate that a limited resection for patients with poor-risk clinical stage I carcinoma of the lung has an advantage over radiotherapy, especially for tumors measuring less than 2 cm in longest diameter.

Adenocarcinoma↗
PubMed1995

Active oxygen generated in the process of carcinogen metabolism can induce oxidative damage in nuclei.

In the present study, we examined whether active oxygen formed in the process of 4-nitroquinoline 1-oxide (4NQO) reduction by DT-diaphorase could induce oxidative stress on the pulmonary nuclei. The rapid production of OH- radical-like species after the start of the 4NQO reduction was observed, and subsequent induction of nuclear lipid peroxidation occurred. In conjugation with this event, DNA damage estimated as DNA single strand breaks (DNA-SSB) increased in a time-dependent manner. The induction of this DNA damage was partially inhibited by mannitol or vitamin E treatment. These findings suggest that the active oxygen generated in the process of the 4NQO reduction can induce oxidative damage on the pulmonary nuclei.

4-Nitroquinoline-1-oxide↗
PubMed1995

Determination of the efficiency of K99-F41 fimbrial antigen vaccine in newborn calves.

Semipurified K99 and F41 fimbrial antigens were used to prepare an oil-emulsified vaccine against bovine enterotoxigenic colibacillosis. Nine Nelore cows about 7 months pregnant were divided into 3 groups (A, B and C) of 3 animals each, which received different doses of vaccine (1,500 HU, 750 HU and 380 HU, respectively) 8 and 2 weeks before delivery, in the neck by the subcutaneous route. As a control (group D), 3 pregnant cows of the same breed were not vaccinated for later challange of their calves. Vaccine efficiency was measured by the serological tests double diffusion and ELISA. Challenge of calves from the vaccinated and from the three control unvaccinated cows was carried out with the virulent Escherichia coli B41 strain (0101, STa+, K99+, F41+). Two of the 3 calves from the unvaccinated cows died within 48 h with acute diarrhea. E. coli B41 was recovered as pure culture from their stools. In contrast, none of the calves born from vaccinated cows presented diarrhea. These data suggest that the antibody transfer to calves through colostrum gave full protection against the challenge. This semipurified fimbrial vaccine against K99-F41-harboring strains is the first oil-emulsified immunogen prepared in Brazil, which was not only efficient, but also had no adverse effects on vaccinated pregnant cows.

Animals↗