Search PubMed⌕ Search

Biomedical subjects

T Taniguchi

Publications and source records attributed to T Taniguchi.

At least 613 records · Page 34Linked to original sources
PubMed1991

Rotatostereoradiography: a new radiodiagnostic method--development of a new three-dimensional radiodiagnostic device and evaluation in neurosurgical clinics.

The rotatostereoradiographic device uses an x-ray tube coupled with an image intensifier rotating through a 180 degree arc in 2.25 seconds. The rapidly rotating x-ray tube allows 180 degree-arc angiograms to be obtained with a single injection of contrast medium. Subtracted fluoroscopic angiograms can be viewed immediately after injection of the contrast medium with digital recording. These three-dimensional images are displayed on side-by-side monitors stereoscopically. The mortality and morbidity of subarachnoid hemorrhage can only be greatly reduced by surgical treatment of unruptured aneurysms and arteriovenous malformations detected by a wide survey of subarachnoid hemorrhage. Such a wide survey would be possible utilizing intra-arterial digital subtraction angiography via the ascending aorta and this new three-dimensional radiodiagnostic method. A fluoroscopic device must be used to allow easier manipulation of the catheter from the axillary or brachial artery.

Adult↗
PubMed1991

[Mood congruent effects by music on word cognition].

Two studies investigated the mood congruent effects of music on word cognition. In both studies, bright or sad music was used in order to induce elated or depressed mood, and subjects were assigned to either the bright or the sad music condition. In Study 1, positive and negative personality trait words and non-words were presented with the music to examine the effect on incidental recall. Thirty-one subjects were asked to judge whether the words were positive or negative as quickly and accurately as possible. In Study 2, 37 subjects were presented with ambiguous personality trait words without and with music to examine how their interpretations of ambiguous stimuli were affected by music. The results showed the mood congruent effects on recall, interpretation, and response time, and these findings agreed with those obtained from other studies of the mood effects on cognition, especially on recall. It was suggested that music induces a certain mood, which influences on cognitive processes of other stimuli.

Adult↗
PubMed1991

Thymic atrophy in type 2 reovirus infected mice: immunosuppression and effects of thymic hormone. Thymic atrophy caused by reo-2.

Suckling mice infected with reovirus type 2 showed a thymic atrophy followed by a marked suppression of the antibody, production to SRBC (a T cell dependent antigen) and bacterial LPS, when measured by the splenic PFC assay. The PFCs produced were sometimes less than 1% of uninfected control animals. Histologically the thymus was usually smaller than normal, and atrophy of the cortex and increased number of Hassal's bodies were observed. Number of nucleated cells in the thymus of infected mice showed 90% decrease as compared to uninfected mice. The spleen, although larger in size, showed depletion of lymphocytes from the thymus-dependent and follicular areas. No viral replication was detected in lymphatic organs using virological methods. Virus-infected mice transferred with the splenocytes or thymocytes from age-matched uninfected mice restored the antibody production against SRBC to normal levels. Thymocytes were more efficient than splenocytes in enhancing the antibody production in virus-infected mice. Injection of several different kinds of immunopotentiating agents enhanced the antibody production to SRBC, although LPS exacerbated the unresponsiveness. Thymic hormones such as FTS and TP5 enhanced antibody production to SRBC and LPS more efficiently than MDP. Flow cytometric analysis showed that percentage of CD4+ single positive cells was slightly increased in virus-infected mice treated with FTS, while there was no difference in the phenotypic distributions of thymocyte subpopulations among virus-infected mice, FTS-untreated and FTS-treated normal mice.

Age Factors↗
PubMed1991

[Cellular responses by cytokines--gene regulation in the IFN system].

Interferon (IFNs), as a class of antiviral cytokines, are also known as "negative growth regulators," they inhibit the growth of a variety of normal and malignant cells. Normally, Type I IFNs (i.e. IFN-alpha, -beta) are not induced, but viruses and a number of other cytokines transiently activate the IFN genes. In order to elucidate the molecular mechanisms of cellular responses by viruses and cytokines, we have identified two nuclear factors, IRF-1 and IRF-2, both bind to the regulatory cis-elements of IFN and IFN-responsive genes. The genes encoding IRF-1 and IRF-2, have been cloned and extensively characterized. The IRF cDNA expression studies in factor-negative cells have revealed IRF-1 and IRF-2 to function as transcriptional activator and repressor, respectively. In normal cells, the IRF genes are subject to induction through stimuli such as viruses and cytokines including IFNs per se. The findings provide evidence for the presence of an elaborate network of cytokines system wherein the IRFs play a crucial role for the cytokine-mediated cellular responses.

Amino Acid Sequence↗
PubMed1991

[A case report of the limited form Wegener's granulomatosis].

The classical from of Wegener's granulomatosis (WG) is a necrotizing granulomatous angiitis that involves the upper and lower airways, and kidneys. A limited form of WG is characterized by pulmonary lesions identical to those of classical form WG without renal involvement. The authors report a case of limited form WG. A 58-year-old Japanese woman was admitted because of an abnormal pulmonary shadow. Pathological examination revealed granulomatous angiitis consistent with WG. No other organ involvement was found. The pulmonary shadow improved with cyclophosphamide therapy. The patient is now well and without evidence of exacerbation of the disease 18 month after the discharge.

Cyclophosphamide↗
PubMed1991

[Alpha 2plasmin-inhibitor . plasmin complex (PIC)--useful diagnostic and prognostic parameter].

To evaluate the diagnostic and prognostic value of PIC, we compared it with the DIC score (which is calculated from platelet count, fibrinogen, FDP, and prothrombin time). We examined 182 samples from 60 patients with coaglo-fibrinolytic abnormalities. For the diagnosis of DIC, the sensitivity of PIC was significantly higher than that of DIC score (78.46% vs 43.08%; chi 2-test p less than 0.01), although the specificity of PIC was significantly lower than that of DIC score (32.48% vs 69.23%; chi 2-test p less than 0.01). For the prediction of prognosis, the peak value of PIC and DIC score during the patient's clinical course were evaluated. The non-survivors (n = 33) had significantly higher levels of peak PIC and DIC scores than the survivors (n = 27) (peak PIC: 6.1 + 9.0 micrograms/ml vs 2.2 + 3.3, p less than 0.05; peak DIC score: 4.6 + 2.4 points vs 3.3 + 2.2, p less than 0.05). The patients with a peak PIC of more than 4.0 micrograms/ml had a mortality of over 90%. These results show that PIC is a useful diagnostic and prognostic parameter.

Aged↗
PubMed1991

[An epidemiological study on the prevalence of the narrow chamber angle in Japanese].

Primary angle-closure glaucoma (PACG) has been reported to be more prevalent in Orientals than in Caucasians. However, our knowledge about the epidemiology of narrow angle and PACG in Orientals is still extremely limited. To determine the prevalence of narrow angle and PACG in Japanese, we carried out gonioscopic and oculometric examinations as a part of the first nationwide, multicenter glaucoma survey in Japan. We also estimated the angle width by means of van Herick's method to assess the efficacy of this method in detecting narrow angle. Of 1,979 inhabitants 40 years or older of a town in Gifu Prefecture, 585 (29.6%) participated in the study and underwent tonometric, gonioscopic and oculometric examinations. The width of the angle was estimated by van Herick's method prior to gonioscopy. Of the group tested, the prevalence of grade 0 to 2 angles (Shaffer's classification) was found in 8.0%, which was significantly more frequent than among Caucasians. The prevalence of grade 1 or narrower angle and PACG was 2.6% and 0.3%, respectively, neither of which was significantly different from rates reported among Caucasians. Using the gonioscopic determination as a gold standard, van Herick's method was noted to have a sensitivity of 77% and a specificity of 94% in identifying eyes with the angle of grade 2 or narrower, while both the sensitivity and specificity of this method were above 90% in detecting an angle of grade 1 or narrower. It was concluded that van Herick's method was useful in detecting the extremely narrow angle.

Adult↗
PubMed1991

[On factors related to the width of anterior chamber angle--multivariate analysis of biometrically determined values].

Primary angle-closure glaucoma (PACG) is associated with certain biometric ocular features such as shallow anterior chamber, axial hyperopia, increased thickness of the lens and small corneal diameter. The vast majority of previous studies on PAGG has shown that females are affected more frequently than males. In an attempt to study the relationship between the angle width and ocular dimensions, we carried out gonioscopic examination and biometric measurements (corneal diameter, corneal radius, anterior chamber depth, lens thickness, relative lens position and axial length) in 1,169 eyes of 585 adult subjects who participated in the glaucoma screening in Gifu Prefecture. It was found that the angle width significantly correlated with each biometric value. The coefficient of determination calculated by multiple regression analysis was 0.41, suggesting that factors other than these are involved in determining the angle width. When the angle width of females was compared to that of males with identical refractive errors and biometric values, the angle width of females was significantly narrower than that of males. Hence, the difference in ocular dimensions does not adequately explain the higher incidence of narrow angle in females. Increased asymmetry of angle width between a pair of eyes with aging appeared to be related to asymmetry of lens thickness, anterior chamber depth and lens position.

Adult↗
PubMed1991

[A case of inoperable advanced gastric cancer with effective treatment by local administration of OK-432, intra-abdominal administration of CDDP, and long-term high-dose mitomycin C, and UFT].

A 61-year-old male diagnosed as Borrmann type 3 advanced gastric cancer was operated, but could not be resected because of the invasion to the pancreas and the lymph nodes metastases. So, local administration of OK-432 20 KE, intra-abdominal administration of CDDP 50 mg, and long-term intermittent intravenous administration of MMC a total amount of 1480 mg, and oral administration of UFT were performed. As the result of this therapy, the tumor was reduced in size. Three years and seven months after the operation, he feels well. Because of this combined therapy, his renal function was made worse.

Adenocarcinoma↗
PubMed1991

Electron microscopic localization of acridine orange binding to euchromatin in human neuroblastoma cells.

The purpose of the present study was to examine the distribution pattern of acridine orange (AO) chromatin interaction products (AOCI) in human neuroblastoma IMR-32 cells and to test whether AO labeling is correlated with BrdU incorporation, and immunohistochemical localization of DNA polymerase alpha, and human N-myc-gene product. Effects of aphidicolin, alpha-amanitin, and actinomycin D on visualization of AO binding to euchromatin and on N-myc-gene expression were also examined. About 25% of the cell nuclei in logarithmic growth phase were immunohistochemically demonstrated to be labeled with BrdU after incubation at 37 degrees for 30 min, indicating cells in DNA synthesis. Most of the cell nuclei showed positive immunoreactivity to DNA polymerase alpha, while human N-myc gene product was found in about 60-80% of the cell nuclei. Electron microscopic studies revealed that about 25% of neuroblastoma cells showed characteristic AOCI within cell nuclei. In the presence of aphidicolin, alpha-amanitin, and actinomycin D, positive cells for N-myc gene product decreased markedly. Percentages of AO positive cells and numbers of AOCI per cell nucleus also showed a marked decrease. But northern blot analysis demonstrated that the expression level of N-myc gene was only repressed by the transcriptional inhibitors alpha-amanitin and actinomycin D. However, no repression was caused by aphidicolin. The present and previous studies of the authors suggest that the ultracytochemical AO method may be indicative for conformational changes of chromatin of cells confined to the cell cycle. Inhibitors of RNA and DNA synthesis then may change the conformational state of chromatin.(ABSTRACT TRUNCATED AT 250 WORDS)

Acridine Orange↗
PubMed1991

Aberrant accumulation of phospholipase C-delta in Alzheimer brains.

Since phosphoinositide-specific phospholipase C (PLC) is one of the key molecules in signal transduction, the authors assessed its involvement in Alzheimer's disease (AD). Immunostaining of a specific antibody against the PLC isozyme, PLC-delta, demonstrated that this enzyme was abnormally accumulated in neurofibrillary tangles (NFT), the neurites surrounding senile plaque (SP) cores, and neuropil threads in AD brains. Western blot analysis confirmed that PLC-delta was concentrated in the paired helical filament (PHF)-rich fraction of AD brains. Antibodies to other PLC isozymes did not produce positive immunostaining of these pathologic structures. Moreover, diffuse and amorphous deposits of PLC-delta were found to precede the accumulation of fibrillary deposits. These results suggest that PLC-delta accumulation is a crucial event that ultimately may contribute to the formation of PHF.

Aged↗
PubMed1991

Molecular cloning of the L-phenylalanine transaminase gene from Paracoccus denitrificans in Escherichia coli K-12.

The L-phenylalanine transaminase gene of Paracoccus denitrificans was cloned by a shotgun method using the Escherichia coli K-12 mutant DG30, which lacks three distinct transaminase genes. Plasmid pPAP142 was constructed by inserting a 2.2-kb fragment carrying the transaminase gene into pUC18. Strain E. coli K-12 HB101 cells harboring the plasmid produced 20-fold to 30-fold more transaminase than wild type P. denitrificans cells. The nucleotide sequence of the 2.2-kb fragment was determined, revealing that the deduced amino acid sequence of the transaminase of P. denitrificans is similar to that of other transaminases.

Amino Acid Sequence↗
PubMed1990

Absence of the type I IFN system in EC cells: transcriptional activator (IRF-1) and repressor (IRF-2) genes are developmentally regulated.

Interferons (IFNs) are a heterogeneous family of cytokines that exhibits multiple biological activities. Upon viral infection, expression of type I IFNs (i.e., IFN-alpha and IFN-beta) is induced in a variety of differentiated cells but not in cells of embryonal origin. IRF-1 and IRF-2, which bind to the same cis-elements within the promoters of type I IFN and IFN-inducible MHC class I genes, were identified previously. Here we demonstrate that the expression of both IRF and IFN genes is developmentally regulated in mouse EC cells; these genes become functional only after cell differentiation. Furthermore, cDNA-directed IRF-1 produced in undifferentiated but not differentiated EC cells efficiently activates the transfected IFN-alpha and IFN-beta and endogenous IFN-alpha genes, whereas IRF-2 represses the IRF-1 effects. These findings emphasize the dual function of the IRF-responsive cis-elements as positive and negative regulators, since they can be occupied by transcriptionally active or inactive IRF molecules. This type of regulatory mechanism might operate in other cytokine systems.

Animals↗
PubMed1990

Characterization of the heterodimeric complex of human IL-2 receptor alpha.beta chains reconstituted in a mouse fibroblast cell line, L929.

The receptor for IL-2 has been known to exist in three forms on the basis of their affinities to IL-2: high, intermediate, and low affinity forms. Two IL-2R components have been identified as IL-2R alpha (p55, Tac Ag) and IL-2R beta (p70-75) chains, both bind IL-2 with low and intermediate affinities, respectively. Recently, we cloned human IL-2R beta chain cDNA and demonstrated that the cDNA product binds IL-2 with intermediate affinity and forms high affinity IL-2R with coexpressed IL-2R alpha chain in a human T cell line, Jurkat. In this study, we report the establishment of the mouse fibroblast transformants expressing either the IL-2R beta chain alone or both the IL-2R alpha and IL-2R beta chains. In contrast to lymphoid cells, significant IL-2 binding was not detected in the transformants expressing the IL-2R beta chain alone at IL-2 concentrations (50 pM to 10 nM) generally utilized. Nonetheless, the transformants expressing both IL-2R alpha and IL-2R beta chains displayed two forms of the IL-2R with high and low affinities to IL-2. However, neither IL-2 internalization nor signal transduction via the high affinity IL-2R complex were observed in the L929 transformants. Those findings suggest that the interaction of the IL-2R beta chain with the IL-2R alpha chain occurs in the absence of additional lymphoid specific component(s) to form high affinity IL-2R, but that this interaction is insufficient for IL-2 internalization and signal transduction just as observed in lymphoid cells. The experimental approach described here may allow further dissection of the molecular architecture of the IL-2R complex in the ligand binding, internalization, and signal transduction.

Animals↗
PubMed1990

Protein-tyrosine phosphorylation and aggregation of intact human platelets by vanadate with H2O2.

The ability of vanadate with H2O2 to stimulate protein-tyrosine phosphorylation and aggregation in intact human platelets was observed. Upon stimulation by these agents, there was a change in the amount of protein-tyrosine phosphorylation of four bands with molecular masses of 80-, 76-, 53- and 38-kDa proteins. The tyrosine phosphorylation in these four bands increased gradually and reached a maximum level at 2 min and then decreased. Aggregation of platelets was also induced by these agents in a dose dependent manner. The observation that the aggregation was preceded by the increase in tyrosine phosphorylation of these proteins suggests that tyrosine phosphorylation may be involved in an early stage of platelet aggregation.

Blood Platelets↗