[In vivo mutation analysis with transgenic mouse].
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Aging↗
Biomedical subjects
T Ono
Publications and source records attributed to T Ono.
Electroencephalogram spectral characteristics after alcohol ingestion in Japanese men with aldehyde dehydrogenase-2 genetic variations: comparison with peripheral changes.
BACKGROUND: Electroencephalographic (EEG) activity induced by alcohol ingestion may be influenced by individual differences in alcohol metabolism. Specifically, an absence of the low Km isozyme of aldehyde dehydrogenase (ALDH), found in many Asians, may be related to alterations of EEGs. METHODS: EEG power spectral changes induced by 0.4 ml/kg of alcohol ingestion were compared in two groups of Japanese subjects: NN (ALDH2*1/1, n = 19) and ND (ALDH2*2/1, n = 12). Peripheral changes in heart rate and facial skin temperature were evaluated after the same treatment. Blood ethanol, acetaldehyde, and catecholamine levels were determined to evaluate mediation of the ethanol metabolite, acetaldehyde, and its indirect action on EEGs through the effects on peripheral systems. RESULTS: As expected, blood acetaldehyde was about 10-fold higher in the ND subjects compared with the NN subjects during the postingestion period. Ethanol produced characteristic EEG changes during and after ingestion. The ND subjects, however, displayed brief periods of decrease in slow alpha immediately after alcohol ingestion and showed no long-term EEG changes. The EEG changes were parallel to peripheral changes. CONCLUSIONS: The lack of increased EEG power in the ND subjects may be partly mediated by a direct action of the high concentration of acetaldehyde in the central nervous system that penetrates from the peripheral blood. In addition to this direct action of acetaldehyde, an indirect action, such as feedback from peripheral changes, might prevent the characteristic increase in alpha and beta power observed in the NN subjects.
Acetaldehyde↗
[Peripheral vascular pain].
Peripheral vascular pain consists of complex factors, and may be divided into three types, i.e., arterial pain, microvessel pain and venous pain. Among these, arterial pain requires intensive pain control because of severe ischemic pain due to arterial obstruction. Under ischemic condition, adenosine is generated, and activates unmyelinated afferents to produce pain. In addition to adenosine, acidic pH itself produces pain and sensitization to mechanical stimuli. Moreover bradykinin generated by kallikurein in acidic pH can produce pain. Nerve block is indicated to improve tissue circulation and to relieve pain. Endoscopic thoracic sympathectomy is indicated for upper extremities, and high frequency thermocoagulation is applied for lumbar sympathectomy. Spinal cord stimulation and the gene therapy with vascular endothelial growth factor have also been reported effective.
Electric Stimulation Therapy↗
[Responses to a questionnaire on laboratory examinations performed by graduates of Jichi Medical School in rural practice].
Graduates from Jichi Medical School are obligated to work at rural clinics or hospitals, where most of them are the only medical doctor in the house. Our need to continuously improve medical education, including the learning that takes place in the clinical setting, requires us to understand how these graduates actually use laboratory examinations and what examinations they find most important in their practice. We designed a questionnaire to address these questions. Three hundred sixty-eight graduate physicians working at clinics or hospitals in both rural or urban areas were asked to complete the questionnaire, providing information on the size of their institution, the laboratory equipment and examinations that they have direct access to, and what examinations they find most important. Two hundred seventy-eight (75.5%) of the 368 recipients responded. More than seventy percent of the respondents reported that their institutions had electrocardiographs, abdominal and cardiac ultrasonographs, urinalysis test paper, and portable blood glucose meters; and more than half of them reported having used these instruments without assistance in emergency situations and outside of ordinary office hours. Moreover, a majority of the respondents said that they considered it important that a physician is able to use these instruments without the help of other staff members. These responses clearly show the importance and usefulness of covering examination techniques and the principles of laboratory medicine in medical education.
Attitude of Health Personnel↗
[Education of medical mycology for dermatologists in Japan].
Inquiries were made to estimate the level of dermatological practice and to elucidate the mycological education of 147 recruits who applied to take the specialized examination offered by the Japanese Dermatological Association in August 2000. The potassium hydroxide (KOH) examination was performed on the following percentages of the 147 recruits: for tinea corporis, 79.6%; tinea manuum, 76.9%; pityriasis versicolor and tinea cruris, 74.1% and oral candidiasis, 70.1% respectively. Culture examination was applied by 30.6% of the recruits for sporotrichosis, 19.7% for dematiaceous fungal infection and 15.6% for kerion. Ninety-five percent of the recruits had been trained at university hospitals. Another inquiry was made to directors of 380 dermatology clinics (88 university hospitals and 292 other clinics), in June 2000. KOH-examinations had been made at 94% of the university hospitals and 83% of the other clinics for all of suspected mycosis, whereas culture examinations were made at only 8% and 3% respectively. Further mycological examinations such as identification of the isolates to species level had been made at 73% of the university hospitals. It is postulated that 88% of the university hospitals have facilities to offer a medical mycology education to dermatologists. From these results it is concluded that the available mycological education is insufficient to satisfy the levels of dermatology specialists for clinical practice.
Adult↗
[Effect of probucol on the concentration of cyclosporin A in patients with nephrotic syndrome].
The first choice of therapy for nephrotic syndrome is steroid, and cyclosporin A(CyA) or other immunosuppressants are selected for steroid resistant or recurrent cases. Nephrotic syndrome accompanies hyperlipidemia for which HMG-CoA reductase inhibitors are mainly used. On the other hand, probucol is used in cases showing inadequate effects or some adverse reactions under treatment with HMG-CoA reductase inhibitors. Recently, we experienced several cases whose blood levels of CyA were decreased to about half that before the combined use of probucol, and concomitant administrations were discontinued. Based on these cases, we considered that the use of probucol should be prescribed in patients with nephrotic syndrome accompanying hyperlipidemia giving preference to CyA treatment. In cases of unavoidable usage of probucol, CyA dose adjustments are required on the basis of frequent CyA blood level monitoring.
Adult↗
[Pulmonary mucormycosis caused by Cunninghamella bertholletiae in a non-immunocompromised woman].
A 74-year-old woman was admitted for further examination because of an abnormal nodular shadow and thickening of the bronchovascular bundle in the left upper lobe on chest radiography and CT. The findings from a transbronchial biopsy specimen were not conclusive. A thoracoscopic lung biopsy specimen revealed a fungal infection, and partial resection of S1 + 2 of the left upper lobe was carried out. In the dilated bronchus, mucus of high viscosity was seen. Lymphocytes and plasma cells had infiltrated into the bronchioles and alveoli. Fungus was cultured from the mucus, and the morphological characteristics showed Cunninghamella bertholletiae. Pulmonary mucormycosis caused by C. bertholletiae in a non-immunocompromised person is very rare. Furthermore, this patient also had a wheeze, eosinophilia, elevation of the serum IgE level, and was positive for specific IgE to Mucor. We therefore consider that this case was an incomplete type of allergic bronchopulmonary fungusis (ABPF).
Aged↗
[A case of idiopathic interstitial pneumonia that responded well to intermittent intravenous administration of high doses of cyclophosphamide and a steroid].
A 78-year-old man was hospitalized on February 29, 2000 because of dyspnea. A chest radiograph showed diffuse bilateral interstitial shadows associated with pulmonary volume loss. We could not obtain histological evidence of idiopathic interstitial pneumonia (IIP) because of his advanced age and severe respiratory dysfunction. IIP was diagnosed on the basis of radiographic findings and clinical symptoms. The patient was intubated and mechanical ventilation was performed. After one course of pulsed cyclophosphamide (CPM) and methylprednisolone therapy, the hypoxemia improved and it became possible to wean the patient from the ventilator. After five courses of pulsed CPM therapy, the dose of oral corticosteroid was tapered. CPM was administered safely without any severe side effects. Pulsed CPM therapy appears to be a viable alternative method of treatment for IIP.
Aged↗
Two-dimensional changes in soft tissue profile following surgical mandibular advancement in Japanese retrognathic adults.
The purpose of this study was to evaluate changes in the hard and soft tissues and to test a preliminary method for predicting the soft tissue profile changes in 14 Japanese retrognathic patients who underwent surgical mandibular advancement. A pair of pre- and postoperative lateral cephalograms was taken for each subject. A paired t test identified significant hard and soft tissue changes following surgery. A Pearson correlation analysis was used to identify soft tissue changes for hard tissue changes in the horizontal and vertical dimensions. Multiple regression models were generated to predict postoperative variables based on preoperative variables. Significant changes in the hard and soft tissues were found in the area inferior to the point Stomion in both the horizontal and vertical dimensions. The soft tissue changes demonstrated a significant correlation not only with the corresponding hard tissue, but also with noncorresponding anatomical points. Moreover, the tendency of changes in the soft tissue was different in the lower lip area from the chin area in both the horizontal and vertical dimensions. Significant R2 and higher contribution ratio were obtained from the multiple regression analysis for the chin area compared to the lower lip area.
Adult↗
Serological analysis of BALB/C methylcholanthrene sarcoma Meth A by SEREX: identification of a cancer/testis antigen.
Antigens of BALB/c methylcholanthrene-induced fibrosarcoma Meth A recognized by the host humoral immune response were investigated by serological analysis of antigens by recombinant expression cloning (SEREX). Immunoscreening a cDNA library from Meth A (Kgamma) cells (Meth A retrovirally transfected with murine IFN-gamma cDNA) with sera from BALB/c mice growing parental Meth A transplants identified 10 antigens. One of them, OY-MS-4, showed characteristics of a cancer/testis (CT) antigen. Nucleotide sequence analysis revealed that OY-MS-4 was identical to a mouse placenta and embryonic expression gene (pem) known to be selectively expressed during embryogenesis and in transformed cell lines. In adult mice, expression of OY-MS-4 was restricted to testis and placenta. Four of 6 methylcholanthrene-induced fibrosarcomas in BALB/c mice showed strong expression of OY-MS-4. In 6 T-cell leukemias, only a dimethylbenzanthracene-induced leukemia, EL4 (C57BL), showed strong expression. Two other tumors, A20.2J and P815, induced by ethylnitrosourea and methylcholanthrene, respectively, also strongly expressed OY-MS-4. The other 9 gene products identified in Meth A by SEREX were expressed in all 15 tumors tested and in a range of normal tissues. Sequence analysis of cDNA inserts coding for the SEREX-defined antigens showed no evidence of mutation. Despite the expression of OY-MS-1-10 antigens in methylcholanthrene sarcomas other than Meth A, no antibody was detected in the sera of mice bearing these other sarcomas. The basis for the unique immunogenicity of OY-MS-1-10 presented by Meth A, but not by other syngeneic tumors expressing these gene products, is unknown.
Amino Acid Sequence↗
Effects of reward anticipation, reward presentation, and spatial parameters on the firing of single neurons recorded in the subiculum and nucleus accumbens of freely moving rats.
The subiculum is the major output of the hippocampal formation (involved in spatial processing). Subicular afferents innervate the nucleus accumbens, which is thought to integrate limbic reward information with motor output. Rats were chronically implanted with extra-cellular recording electrodes aimed at both structures to investigate the functional relationship between them. Animals were then trained on a spatial task in which they searched for random locations where they would receive rewarding medial forebrain bundle stimulation. At random times a cue tone was sounded, indicating that the reward location was in the center of the environment. Rats quickly learned to run to the center upon hearing the tone in order to receive a reward. Simultaneously recorded groups of up to eight subicular and accumbens neurons were found to display alterations in firing rate after rewarding medial forebrain bundle stimulation. Moreover, neurons in both subiculum and accumbens displayed alterations in firing rate prior to arrival at the center during cued runs, i.e. they anticipated predictable rewards. Subicular and accumbens firing was also correlated with spatial location. However, neurons in accumbens were more likely to respond to task events, and these responses were more varied, than those seen in subiculum. Thus, while convergence of spatial and reward information occurs at the level of single cells in both subiculum and nucleus accumbens, these structures also display functional localization.
Acoustic Stimulation↗
Retrograde cerebral perfusion in human brains.
Retrograde cerebral perfusion via the superior vena cava during deep hypothermic circulatory arrest has evolved as a means of cerebral protection in aortic-arch surgery. We showed, with use of fluorescein retinal angiography, that during retrograde cerebral perfusion, fluorescein injected into the superior vena cava entered the retinal venules, flowed to the capillaries, and subsequently, to the retinal arterioles. Since the retina is embryologically part of the brain, we conclude that this procedure does allow blood to perfuse in a retrograde way through the human brain.
Adult↗
TOK-1, a novel p21Cip1-binding protein that cooperatively enhances p21-dependent inhibitory activity toward CDK2 kinase.
A p21(Cip1/Waf1/Sdi1) is known to act as a negative cell-cycle regulator by inhibiting kinase activity of a variety of cyclin-dependent kinases. In addition to binding of the cyclin-dependent kinase to the N-terminal region of p21, p21 is also bound at its C-terminal region by proliferating cell nuclear antigen (PCNA), SET/TAF1, and calmodulin, indicating the versatile function of p21. In this study, we cloned cDNA encoding a novel protein named TOK-1 as a p21 C-terminal-binding protein by a two-hybrid system. Two splicing isoforms of TOK-1, TOK-1alpha and TOK-1beta, comprising 322 and 314 amino acids, respectively, were co-localized with p21 in nuclei and showed a similar expression profile to that of p21 in human tissues. TOK-1alpha, but not TOK-1beta, directly bound to the C-terminal proximal region of p21, and both were expressed at the G(1)/S boundary of the cell cycle. TOK-1alpha also preferentially bound to an active form of cyclin-dependent kinase 2 (CDK2) via p21, and these made a ternary complex in human cells. Furthermore, the results of three different types of experiments showed that TOK-1alpha enhanced the inhibitory activity of p21 toward histone H1 kinase activity of CDK2. TOK-1alpha is thus thought to be a new type of CDK2 modulator.
Amino Acid Sequence↗
Supine cephalometric study on sleep-related changes in upper-airway structures in normal subjects.
The purpose of this study was to examine sleep-related changes in the upper airway and surrounding structures including the mandible, hyoid bone, and cervical vertebra in normal subjects using lateral cephalograms in the supine position. Eleven male and nine female healthy adults participated in this study. Supine cephalograms were taken at end-expiration during wakefulness and in stage 1-2 non-rapid-eye-movement (NREM) sleep judged from the electroencephalogram and respiratory monitoring. A paired t-test was used to compare differences between the values measured during wakefulness and sleep. A significant increase in the amount of jaw opening was observed during sleep. The anteroposterior width of the upper airway was significantly decreased during sleep. The distances between the hyoid bone and the mandibular symphysis and between the cervical vertebra and the hyoid bone were significantly decreased during sleep. Consequently, the distance between the cervical vertebra and the mandibular symphysis was significantly decreased. These results suggest that the upper-airway dimension is significantly decreased and relatively small structural changes are induced during sleep in normal subjects.
Adult↗
Pulsed EPR studies of doublet signal and singlet-like signal in oriented Ca2+-depleted PS II membranes: location of the doublet signal center in PS II.
Doublet signal and singlet-like signal induced in Ca(2+)-depleted PS II were investigated by pulsed EPR in one-dimensionally oriented photosystem (PS) II membranes. The doublet signal showed marked angular dependent change in its spectrum in term of the applied magnetic field, indicating that the magnetic dipole-dipole interaction is mainly responsible for the doublet signal. The singlet-like signal also showed angular dependence, which was less pronounced than that of the doublet signal. The parameters of dipole and exchange interactions used to simulate the doublet signal indicate that the signal arises from a magnetically coupled organic radical pair. Angular dependence of the doublet signal indicates that the radius vector of the radical pair (r) and the normal of the thylakoid membrane is at an angle of 65 degrees. Pulsed ELDOR studies in the oriented membranes indicate that the vector (R) connecting the doublet-signal center with the Y(D)(*) radical and the plane of the thylakoid membrane are at an angle of 8 degrees. Furthermore, the angle between the projections of the R and r vectors on the plane of the thylakoid membrane was determined to be 64 degrees. The location of the doublet-signal species in PS II is discussed.
Anisotropy↗
Photoaffinity labeling and site-directed mutagenesis of rat squalene epoxidase.
Squalene epoxidase (SE) (EC 1.14.99.7) is a flavin-requiring, non-cytochrome P-450 oxidase that catalyzes the conversion of squalene to (3S)-2,3-oxidosqualene. Photolabeling and site-directed mutagenesis were performed on recombinant rat SE (rrSE) to elucidate the location and roles of active-site residues important for catalysis. Two new benzophenone-containing analogs of NB-598, a nanomolar inhibitor of vertebrate SE, were synthesized in tritium-labeled form. These photoaffinity analogs (PDA-I and PDA-II) became covalently attached to SE when irradiated at 360 nm. Lys-C digestion and HPLC purification of [3H]PDA-I-labeled rrSE resulted in isolation of a single major peptide. MALDI-TOF mass spectrometry of this peptide indicated a covalent adduct between PDA-I and a tripeptide, Asp-Ile-Lys, beginning at Asp-426 of rat SE. Based on the labeling results, three mutant constructs were made. First, the D426A and K428A constructs showed a 5- to 8-fold reduction in SE activity compared with wild-type enzyme, while little change was observed in the I427A mutant. Second, a set of five mutant constructs was prepared for the conserved region based on the structure of the flavoprotein p-hydroxybenzoate hydroxylase (PHBH). Compared with wild-type, D284A and D407A showed less than 25% SE activity. This reduction also appeared to correlate with reduced affinity of the mutant proteins for FAD. Finally, each of the seven Cys residues of rrSE were individually mutated to Ala. Three Cys substitutions had no effect on SE activity, and substitutions at Cys-500 and Cys-533 showed a 50% lower SE activity. Mutations at Cys-490 and Cys-557 produced proteins with negligible SE activity, implicating these residues as being either structurally or catalytically essential. Chemical modification of wildtype and Cys mutants with a thiol-modifying reagent support the existence of a disulfide bond between Cys-490 and Cys-557.
Affinity Labels↗
Mouse group X secretory phospholipase A2 induces a potent release of arachidonic acid from spleen cells and acts as a ligand for the phospholipase A2 receptor.
Group X secretory phospholipase A2 (sPLA2-X) has recently been shown to possess a powerful potency for releasing arachidonic acid from cell membrane phospholipids. Here, we report the purification of mouse pro- and mature forms of sPLA2-X, as well as its expression and biological functions. Purified pro-sPLA2-X was found to possess a propeptide of 11 amino acid residues attached at the NH2-terminals of the mature protein, and showed as little as 8% of the PLA2 activity of the mature form. Limited proteolysis of pro-sPLA2-X with trypsin resulted in the appearance of the mature form with a concomitant increase in PLA2 activity, suggesting a requirement of proteolytic removal of the propeptide for the optimal activity. The expression of sPLA2-X mRNA was detected in various tissues including the lung, thymus, and spleen, and immunohistochemical analysis revealed its expression in splenic macrophages. In the spleen cells, mature sPLA2-X elicited a prompt release of arachidonic acid with significant production of prostaglandin E2 more efficiently than group IB and IIA sPLA2s. In addition, sPLA2-X was identified as a high-affinity ligand for both native and recombinant form of mouse PLA2 receptor (PLA2R). However, there was no significant difference in the sPLA2-X-induced arachidonic acid release responses in the spleen cells between wild-type and PLA2R-deficient mice. These findings strongly suggest that sPLA2-X possesses two distinct biological functions in mice: it elicits a marked release of arachidonic acid from membrane phospholipids leading to the production of lipid mediators based on its enzymatic potency, and it acts as a natural ligand for the PLA2R that has been shown to play a critical role in the production of inflammatory cytokines during endotoxic shock.
Animals↗
Magnetic vortex core observation in circular dots of permalloy
Spin structures of nanoscale magnetic dots are the subject of increasing scientific effort, as the confinement of spins imposed by the geometrical restrictions makes these structures comparable to some internal characteristic length scales of the magnet. For a vortex (a ferromagnetic dot with a curling magnetic structure), a spot of perpendicular magnetization has been theoretically predicted to exist at the center of the vortex. Experimental evidence for this magnetization spot is provided by magnetic force microscopy imaging of circular dots of permalloy (Ni(80)Fe(20)) 0.3 to 1 micrometer in diameter and 50 nanometers thick.
Journal Article↗