Search PubMed⌕ Search

Biomedical subjects

K Ogata

Publications and source records attributed to K Ogata.

At least 181 records · Page 10Linked to original sources
PubMed1996

Further study on association of 5SrRNA-L5 protein complex and methionyl-tRNA to methionyl-tRNA synthetase in the macromolecular aminoacyl-tRNA synthetase complex.

To obtain direct evidence for the attachment of 5SrRNA-ribosomal L5 protein particles (5SRNP) and methionine-tRNA (tRNA(met)) to methionyl-tRNA synthetase (MetRS) in the macromolecular aminoacyl-tRNA synthetase (ARS) complex of rat liver, a MetRS-5SRNP-tRNA(met) complex was dissociated from the macromolecular ARS complex fraction by n-octyl-beta-D-glucoside (Method I) or by omega-aminooctyl agarose (Method II) chromatography. The dissociated MetRS complex fraction was purified by gel filtration followed by tRNA-Sepharose chromatography using partially purified tRNA(met) in Method I, and by hydrophobic interaction chromatography in Method II. In both methods, final Superdex200 chromatography showed that MetRS activity was present in the region corresponding to the molecular weight of the MetRS-5SRNP-tRNA(met) complex (M(r) 200,000). One main protein band corresponding to the molecular weight of MetRS was observed on SDS-PAGE of the final product, which was concentrated by lyophilizing after dialysis against water. Using serum albumin as an inhibitor of adhesion of L5 to the microconcentrators which was used to concentrate the final product, a distinct L5 band was detected on SDS-PAGE, the intensity of which was comparable to that of the MetRS band. Northern blot analysis of RNA prepared from the tRNA-Sepharose fraction showed the presence of 5SrRNA. Dot blot analysis using an antibody against ribosomal protein L5 showed that L5 was present in the Superdex200 fractions prepared by both methods. The MetRS specific activities in MetRS complex fractions incubated without tRNA increased during the purification procedures, indicating that endogeneous tRNA(met) exists stably in the MetRS complex. 5SRNP and 5SrRNA markedly enhanced the MetRS activity in the MetRS complex, indicating that 5SRNP(A) plays a role as a positive effector of MetRS.

Amino Acyl-tRNA Synthetases↗
PubMed1996

An elastic plastic splint to compress the ear after reconstruction using a temporoparietal fascial flap.

We designed a new splint that is used to compress the ear after reconstruction using the temporoparietal fascial flap method to reduce postoperative swelling rapidly. The splint, which is made of an elastic plastic material, was applied to 3 patients with an acquired ear defect. The application period using this splint was from 10 days after surgery up to 3 to 6 months. Swelling of the reconstructed ear subsided rapidly after application of the splint. The contour was then enhanced in all patients. We were able to apply compression to the region as required, using a sponge attached to the splint. The splint is soft enough to remain in place, even if the patient continues regular activities. We conclude that the elastic plastic splint is useful to compress the ear after reconstruction using the temporoparietal fascial flap method.

Ear Deformities, Acquired↗
PubMed1996

The blood supply to the greater trochanter.

The blood supply to the greater trochanter was investigated in adult rabbits using a hydrogen washout technique. The control blood flow rate of the greater trochanter averaged 13.8 ml/minute per 100 g of tissue. Stripping of the origin of the vastus lateralis muscle did not cause significant decrease of blood flow rate. Blood flow rate was significantly decreased to 10.4 ml/minute per 100 g of tissue after an anterior trochanteric slide osteotomy. Surgical dissection of the proximal soft tissues including the gluteus medius and minimus tendons from the greater trochanter caused significant decrease of blood flow rate to 4.72 ml/minute per 100 g of tissue. The addition of surgical dissection of the proximal soft tissues to anterior trochanteric slide caused a complete arrest of blood flow in the greater trochanter. These results indicate that the greater trochanter receives >2/3 of its blood supply for the extraosseous vascular system in a rabbit model.

Animals↗
PubMed1996

Modification of the gluteus maximus V-Y advancement flap for sacral ulcers: the gluteal fasciocutaneous flap method.

We designed a modified gluteus maximus V-Y advancement flap method for closing a sacral ulcer. The purposes of our method were to simplify the surgical procedure and to avoid a functional deficit of the gluteus maximus muscle that was sacrificed by the conventional method. After excising the sacral ulcer, the V-Y advancement flap is marked on the bilateral buttock. Fascial incision of the gluteus maximus is made at the same incision in the skin. One-third of each medial flap is elevated as a fasciocutaneous flap by dissecting the layer between the fascia and the muscle at the parasacral region. The flaps are then moved medially and sutured. We operated on 24 patients with sacral ulcers using this technique. The patients included 19 with a sacral pressure sore and 5 with a radiation ulcer on the sacrum. Eighteen ambulatory patients also were included in this group. The results showed no flap necrosis in any patient. No functional deficit of the gluteus maximus muscle was observed postoperatively in the ambulatory patients. Average blood loss was 250 ml during the procedure. We conclude that the gluteus V-Y advancement flap as a fasciocutaneous flap is superior to the conventional musculocutaneous flap method.

Adult↗
PubMed1996

Effect of intraatrial reentry on initiation of atrioventricular reentrant tachycardia.

We studied the effect of intraatrial reentry (IAR) on initiation of orthodromic reentrant tachycardia (ORT) in 150 patients with Wolff-Parkinson-White syndrome using His-bundle recording and the atrial extrastimulus technique. IAR was initiated by premature atrial stimulation in 44 patients (29%), and it was followed by ORT in 16 patients (11%). In 8 patients (5%), IAR promoted the initiation of ORT, whereas in 5 patients (3%), IAR inhibited the initiation of ORT. These findings suggest that ORT is frequently induced following IAR. IAR, which was frequently observed during electrophysiological studies, seems to play an important role in the initiation of ORT.

Adult↗
PubMed1996

Protective effect of S-(1,2-dicarboxyethyl)glutathione, an intrinsic tripeptide in liver, heart and lens, and its esters on acetaminophen-induced hepatotoxicity in rats.

The administration of acetaminophen (APAP, 500 mg/kg, i.p.) produced liver necrosis and increased aspartate aminotransaminase (AST) activity in serum. The pretreatment of S-(1,2-diethoxycarbonyl)glutathione isopropyl ester (DCE-Et-GS iPr, 0.5 mmol/kg, p.o.) prevented hepatic necrosis and the elevation of serum AST activity by 99.9%. DCE-Et-GS iPr inhibited APAP-induced hepatotoxicity much more strongly than reduced glutathione (GSH), DCE-GS and other esters of DCE-GS. To clarify this protective effect, the hepatic GSH concentration was determined 2h after APAP administration. It was found that the DCE-Et-GS iPr administration significantly inhibited the GSH depletion caused by APAP, suggesting that the protective effect of DCE-Et-GS iPr on APAP-induced hepatotoxicity was due, at least in part, to the retention of hepatic GSH level.

Acetaminophen↗
PubMed1996

Human T-cell lymphotropic virus type I (HTLV-I) carrier with clinical manifestations characteristic of diffuse panbronchiolitis.

A 45-year-old male was referred due to prolonged productive cough. Despite the fact that bronchoalveolar lavage fluid suggested lymphocytic and neutrophilic alveolitis, the histologic diagnosis of his biopsied lung was diffuse panbronchiolitis-like lesion with infiltration of lymphocytes and plasma cells into respiratory bronchioles but few foamy cells. Serologic examination revealed that he was a carrier of human T-cell lymphotropic virus type I (HTLV-I). Together with uveitis and ulcerative colitis in his past history, the persistent respiratory symptoms of this patient can be attributed to non-neoplastic inflammation due to the chronic HTLV-I infection.

Bronchiolitis↗
PubMed1996

[Therapeutic trials with topical capsaicin cream and iontophoretically applied lidocaine for diabetic painful truncal neuropathy].

We report a 63-year-old man with a history of diabetes mellitus for 23 years. Painful dysesthesia developed in his toes and trunk with weight loss of 2kg in two months, after the therapy for diabetes mellitus. Truncal painful dysesthesia was symmetrically distributed in the bilateral posterior and anterior T8-11 dermatomes, sparing the bilateral lateral tholacic areas. Electromyography showed denervation potentials in bilateral abdominal rectus muscles at the levels of Th8-10. Histopathological study of the biopsied right sural nerve revealed small fiber neuropathy. We suspected the truncal painful dysesthesia of this patient resulted from diabetic small fiber polyneuropathy, which was resistant to ordinary medical treatments such as non-steroidal anti-inflammatory drugs. Capsaicin cream containing 0.075% capsaicin, and lidocaine delivered by iontophoresis were both effective for his painful dysesthesia.

Capsaicin↗
PubMed1996

[Mononeuritis multiplex associated with measles virus infection].

We describe a 19-year-old patient who developed mononeuritis multiplex associated with measles virus infection. On April 30th, 1995, he suffered from fever and skin eruption, which disappeared ten days later. Thirteen days later, he noticed weakness of the fingers of both hands and forearms, and pain on both elbow joints. He was admitted to our hospital on June 12th, 1995. Neurologic examination revealed weakness and sensory disturbance, confined to the distal aspects of the right radial nerve and left median nerve. The electrodiagnostic findings confirmed those of axonal neuropathy in the right radial and left median nerves. Routine laboratory studies were normal. The cerebrospinal fluid test and EEG were normal. The IgG and IgM antibody titers against measles virus continued to be elevated in serum over four months after the onset, while they were not elevated in the cerebrospinal fluid. The corticosteroid therapy was mildly effective. Although the pathogenesis of this case is unclear, we speculate that the mononeuritis multiplex was caused by vasculitis related to the persistent measles virus infection in both elbow areas.

Adult↗
PubMed1996

[The effect of clomipramine to nocturnal periodic hypoxemia in Duchenne muscular dystrophy].

Respiratory insufficiency is a major cause of death in Duchenne muscular dystrophy (DMD). The earliest sign is a hypoventilation which appears in REM sleep. We administered 20 mg of clomipramine hydrochloride before sleep to two DMD patients with periodic nocturnal hypoxemia. The complaints such as morning headache, nausea and somnolence disappeared promptly. Polysomnography revealed complete suppression of REM sleep and disappearance of periodic hypoxemia in both cases. The most important untoward effect was intractable constipation observed in one patient. Although clomipramine dramatically improved the nocturnal periodic hypoventilation, the therapeutic effects lasted less than three months. Permanent REM sleep suppression is requisite for optimal drug therapy of periodic nocturnal hypoventilation in DMD.

Adult↗
PubMed1996

Discovery of Aedes albopictus in Guatemala.

Aedes albopictus was discovered for the first time in Guatemala during June 1995. It was collected in 10 out of 15 localities sampled in and around the community of Puerto Barrios in the Department of Izabal. The location of the positive collections indicates a more rural distribution than Aedes aegypti. Sampling was conducted along the Atlantic Highway up to the capital city to determine the extent of its introduction into the country. Larvae were not found more than 4 km outside of Puerto Barrios. The principal breeding places were rubber tires, glass bottles, and metal drums.

Aedes↗
PubMed1996

[Low-dose chemotherapy].

We examined the clinical results of low-dose chemotherapy in patients with myelodysplastic syndromes (MDS) and refractory acute myelocytic leukemia (AML) who were treated in our institution. Of 34 patients with MDS treated with low-dose cytarabine, 11 achieved complete remission (CR) and six achieved partial remission (PR). The CR rate of patients whose blasts had Auer bodies was significantly higher than that of the patients whose blasts did not. Although the duration of remission was generally short, the overall survival was longer in the responders (CR cases + PR cases) than in the nonresponders. Of 13 patients with MDS treated with low-dose etoposide. one achieved CR and four achieved PR. Of seven patients treated with a combination low-dose therapy consisting of cytarabine and etoposide, two achieved CR. The clinical data in some cases suggested that blasts differentiate into mature myeloid cells in vivo. Low-dose chemotherapy is one therapeutic strategy for MDS and refractory AML. Further studies on the therapy should be conducted to increase the CR rate and to prolong the duration of CR.

Acute Disease↗
PubMed1996

[Different mechanism may underlie respiratory failure of myotonic and Duchenne muscular dystrophies--a pulseoxymetric and spirometric study].

Respiratory failure is an important cause of death in many neuromuscular diseases. We studied the relationship between nocturnal hypoxemia and respiratory muscle weakness by nocturnal pulseoxymetry and spirometry in two major hereditary myopathies, myotonic and Duchenne muscular dystrophies (MD and DMD respectively). In DMD significant nocturnal periodic hypoxemia appears only in cases with vital capacity lower than 20% of its expected value, suggesting that % vital capacity is a useful index of early respiratory failure. In contrast there was no correlation between vital capacity and severity of hypoxemia in MD patients. Therefore, we conclude respiratory muscle weakness is a single important factor which determines the severity of respiratory failure in DMD, while another/other factor (s), such as disturbance of respiratory control or myotonia, may play an important role in MD.

Humans↗
PubMed1996

Doses of solar ultraviolet radiation correlate with skin cancer rates in Japan.

We analyzed trends in the disease rate of skin cancers in the 1976-80 and 1986-90 intervals in the 27 university hospitals in Japan. We also measured doses of solar ultraviolet (UV) radiation at Sapporo, Kobe and Miyazaki to evaluate the relationship between the two in Japan. The rates of basal cell carcinoma (BCC) and actinic keratosis (AK) were higher in 1986-90 than in 1976-80, whereas the rate of squamous cell carcinoma (SCC) was lower in 1986-90 than in the earlier period. The rates of SCC, BCC and AK in the southern part of Japan were about five times higher than those in the north, and the average daily UV dose measured with a Robertson-Berger meter in 1995 was about 1.8 times higher in Miyazaki than in Kobe. That measured by MS-210D UV dosimeter in Sapporo was about 0.53 times lower than in Kobe. These results demonstrate that solar UV dose is higher in the southern part of Japan than that in the northern part, explaining the higher rate of non-melanoma skin cancer in southern part of Japan. A significant increase of AK and BCC may reflect the trend of UV increase in Japan.

Dose-Response Relationship, Radiation↗
PubMed1995

Determination of the NMR solution structure of a specific DNA complex of the Myb DNA-binding domain.

The solution structure of a specific DNA complex of the minimum DNA-binding domain of the mouse c-Myb protein was determined by distance geometry calculations using a set of 1732 nuclear Overhauser enhancement (NOE) distance restraints. In order to determine the complex structure independent of the initial guess, we have developed two different procedures for the docking calculation using simulated annealing in four-dimensional space (4D-SA). One is a multiple-step procedure, where the protein and the DNA were first constructed independently by 4D-SA using only the individual intramolecular NOE distance restraints. Here, the initial structure of the protein was a random coil and that of the DNA was a typical B-form duplex. Then, as the starting structure for the next docking procedure, the converged protein and DNA structures were placed in random molecular orientations, separated by 50 A. The two molecules were docked by 4D-SA utilizing all the restraints, including the additional 66 intermolecular distance restraints. The second procedure comprised a single step, in which a random-cell protein and a typical B-form DNA duplex were first placed 70 A from each other. Then, using all the intramolecular and intermolecular NOE distance restraints, the complex structure was constructed by 4D-SA. Both procedures yielded the converged complex structures with similar quality and structural divergence, but the multiple-step procedure has much better convergence power than the single-step procedure. A model study of the two procedures was performed to confirm the structural quality, depending upon the number of intermolecular distance restraints, using the X-ray structure of the engrailed homeodomain-DNA complex.

Animals↗
PubMed1995

Lineage-unrestricted hematologic response to granulocyte colony-stimulating factor in a patient with refractory anemia with excess blasts.

We report a patient with refractory anemia with excess blasts who showed a lineage-unrestricted hematologic response to granulocyte colony-stimulating factor (G-CSF). After 17 months of a stable disease state, the patient developed pneumonia, progression of cytopenia, and reduced cellularity and blast mass in the bone marrow. He was given G-CSF to overcome the pneumonia. Not only the neutrophil count, but also the platelet count increased soon after initiation of the G-CSF therapy; both counts became normal on the fifth day of the G-CSF therapy. Additionally, the anemia improved gradually. The neutrophil and platelet counts were maintained in the normal range for 3 months after cessation of the G-CSF. In vitro studies showed that G-CSF alone stimulated megakaryocyte colony formation from bone marrow mononuclear cells (BMMNC), and accessory cells in the BMMNC were necessary for expression of this G-CSF-induced in vitro megakaryocytopoiesis. These results suggest that, in coordination with accessory cells, G-CSF stimulated megakaryocytopoiesis in the patient. This case provides valuable information for understanding the mechanisms of a lineage-unrestricted hematologic response to G-CSF, which is very rarely observed in MDS.

Anemia, Refractory, with Excess of Blasts↗
PubMed1995

Immunohistochemical evaluation of tenascin in benign eccrine gland tumors: comparison with laminin and fibronectin.

Surgically resected specimens of skin appendage tumors, spiradenoma, poroma of eccrine glands, syringoadenoma, syringoadenoma papilliferum and mixec tumor of skin were evaluated for tenascin, as well as the basement membrane-associated protein laminin, and the extracellular matrix protein fibronectin, using immunohistochemical methods. In normal sweat glands, tenascin was localized as a delicate, thin band in the immediate vicinity of the basement membrane and laminin was limited to the basement membrane. Tenascin in syringoadenoma was also expressed linearly adjacent to the basement membrane. Mixed tumors of skin showed a characteristic distribution of tenascin in the modified myoepithelial cell area adjacent to the tumor epithelia with a heterogeneous pattern, and particularly strong expression in the hyalinous and chondroid areas. In addition, the localization of laminin in the basement membranes of tumors, intracellular immunoreactivity was observed in syringoadenoma, syringocystadenoma papilliferum, and mixed tumor of skin. Fibronectin reactivity was visualized as a diffuse staining in the tumor stroma of eccrine poroma but its expression was restricted in eccrine spiradenoma. The present study suggests a heterogeneity in the distribution of basement membrane and extracellular matrix proteins in skin appendage tumors and elucidation of their functional roles would assist in understanding the changes in the supporting tumor stroma following neoplastic changes.

Cell Adhesion Molecules, Neuronal↗