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H Sakata

Publications and source records attributed to H Sakata.

At least 91 records · Page 5Linked to original sources
PubMed1996

Selectivity of the parietal visual neurones in 3D orientation of surface of stereoscopic stimuli.

We identified a group of neurones in the posterior parietal cortex of the monkey that responded preferentially to a flat stimulus in a particular orientation on a 3D computer graphics display. We designated these neurones surface-orientation selective (SOS) neurones since they showed tuning to the 3D orientation of the surface. Almost all of the SOS neurones were sensitive to binocular disparity and their responses increased with the width or length of the stimulus, but the responses of only some of them decreased with increasing thickness of the stimulus. These results suggest that SOS neurones extract surface orientation signals from the binocular disparity signals and play an important role in the perception of 3D shape and the visual guidance of hand movement.

Animals↗
PubMed1996

Gastric lesions in 76 patients with adult T-cell leukemia/lymphoma. Endoscopic evaluation.

BACKGROUND: Adult T-cell leukemia/lymphoma (ATLL) is caused by human T-lymphotropic virus type I. Gastric lesions in ATLL have not been described precisely, whereas the clinical features of ATLL have been well documented. The goal of the present study was to review gastric lesions, including gastric involvement, of patients with ATLL who were admitted to our hospital. METHODS: Endoscopic examination of the upper gastrointestinal tract was performed on 76 of 110 patients who were admitted to our hospital between 1981 and 1994. Gastric involvement was diagnosed by histologic examination of biopsy specimens of gastric lesions. Types of gastric lesions, histologic features, and survival periods in patients with ATLL were summarized. RESULTS: Of the 76 patients with ATLL who underwent an endoscopic examination, 23 had gastric involvement (30.3%). Twenty-seven patients had other gastric lesions: 10 with peptic ulcers (13.2%), 8 with gastric erosions (10.5%), 3 with submucosal tumors (3.9%), 2 with hyperplastic polyps (2.6%), 1 with gastric adenoma (1.3%), and 3 with gastric carcinomas (3.9%). The most frequent endoscopic configuration of gastric involvement with ATLL was the diffuse type with ulceration, and the most common histology was large cell type. Among those with the acute type ATLL, the survival period of those patients with gastric involvement was less than that of the patients without gastric involvement. In contrast, the survival period for lymphoma type ATLL did not differ among the groups regardless of gastric involvement. CONCLUSIONS: This study demonstrated that 30.3% of patients with ATLL had gastric involvement and 13.2% had peptic ulcers. Gastric involvement of ATLL was one of the prognostic factors in acute type ATLL, whereas it had no influence on the prognosis of lymphoma type ATLL.

Female↗
PubMed1996

Nucleotide sequences of the M gene of prevailing wild measles viruses and a comparison with subacute sclerosing panencephalitis virus.

We determined the nucleotide sequences of the coding region for the M gene in seven strains of measles virus (MV) that were isolated in Japan between 1984 and 1993. The mutation found among the seven differed from those of laboratory strains. Many of these mutations were the same as those that are characteristic of SSPE viruses. Thus, we suggest that the mutations that have been considered specific to SSPE virus are in fact consensus among prevailing MV.

Base Sequence↗
PubMed1996

Change of renal function during vancomycin therapy in extremely low birthweight infants.

Twenty extremely low birthweight infants were treated with vancomycin (VCM). Their gestational age was 26.3 +/- 1.4 weeks (range 24.0-28.7 weeks) and their birthweight was 829 +/- 133 g (range 562-900 g). At the time of initial administration of VCM, postnatal age was 29.5 +/- 15.8 days (range 5-54 days). Vancomycin was administered in a dose between 9.3 and 11.0 mg/kg every 12 h for a period of 6.3 +/- 2.4 days (range 4-13 days). Serum and urinary specimens were obtained before and after (within 24 h following the last dose) VCM therapy. Serum creatinine and sodium, and urinary N-acetyl-beta-D-glucosaminidase (NAG) activity, creatinine, sodium, and beta-2-microglobulin (BMG) concentrations were measured. Fractional excretion of sodium (FENa) and NAG index (NAG:creatinine ratio) were calculated. There were no significant differences between the before and after VCM treatment in serum creatinine, urinary BMG concentration, FENa and NAG index. No infant showed any symptoms of renal insufficiency. However, the NAG index and FENa increased after treatment in 1 of 20 infants. Vancomycin is effective and safe in the treatment of serious infections in extremely low birthweight infants.

Acetylglucosaminidase↗
PubMed1996

Parietal neurons related to memory-guided hand manipulation.

1. We recorded activity of the hand-manipulation-task-related neurons in the posterolateral bank of the anterior intraparietal sulcus (area AIP) of the monkey parietal cortex during a delayed hand manipulation task. 2. We examined mainly the object-type visual-dominant and visual-and-motor neurons that responded to the sight of objects for manipulation. The majority of these neurons (32 of 48) showed sustained activity during the delay period in the dark before manipulation of preferred objects. 3. Six visual-and-motor neurons showed set-related activity before the hand manipulation in the dark, so that their delay period activity was likely to be related to motor preparation. 4. The delay period activity of 18 visual-dominant and visual-and-motor neurons without set-related activity was likely to represent spatial features of objects, because the majority of the neurons showed the same selectivity in the shape and/or orientation during object fixation and the delay period. 5. Of these 18 neurons, 10 showed sustained activity in the dark after brief illumination of objects during a light-interrupted fixation task, suggesting that they store the short-term memory of objects without the intention to remember. 6. The results suggest that the visual memory of three-dimensional features of objects is likely to be incorporated in area AIP and to be used for the guidance of hand manipulation.

Animals↗
PubMed1996

Effect of FK 506 administered topically versus intramuscularly on suppression of the corneal immune reaction in rats.

The immunosuppressive effect of FK 506 on penetrating keratoplasty in rats was evaluated following intramuscular and topical administration. Implanted corneal grafts were inspected weekly by clinical evaluation for 3 weeks. Cytotoxic T lymphocyte (CTL) activity was measured in the spleen on postoperative day 21, and the grafts were examined histologically. A dose of FK 506, 0.1 mg/kg given intramuscularly, only moderately suppressed CTL activity and the graft failed. In contrast, doses of either 0.024 mg/day topically or 0.3 mg/kg intramuscularly suppressed CTL activity and the grafts remained intact. Results suggest that FK 506 administered topically would be effective in preventing failure of human corneal grafts.

Administration, Topical↗
PubMed1996

Bilateral choroidal osteomas associated with histiocytosis X.

A 15-year-old Japanese girl complained of decreased visual acuity in the left eye of 1-month duration. Histiocytosis X had been diagnosed when she was 2 years old based on examination of biopsies of skin and cervical lymph nodes and bone marrow aspirations. She had been in complete remission for 7 years. She exhibited the characteristic ophthalmoscopic, ultrasonographic, and radiologic features of bilateral choroidal osteomas.

Bone Marrow↗
PubMed1996

Nonhuman primate models of measles.

Wild measles virus isolated in a marmoset lymphoblastoid B95a cell line induced rashes and Koplik's spots when inoculated parenterally in cynomolgus and squirrel monkeys. Marked leukopenia. associated with transient decrease in the CD4(+)-to-CD8+ T-cell ratio also was induced. Virus growth, as well as histologic lesions of necrosis and giant cell formation, was observed in the lymphoid tissues. Thus clinical signs of acute measles were successfully induced in monkeys by inoculation with cell-culture-grown measles virus. These nonhuman primate models of measles will be useful for study of the pathogenesis of acute measles virus infection in terms of generalized clinical signs of disease, leukopenia, and changes in the lymphocyte subsets.

Animals↗
PubMed1996

[Pharmacokinetic, bacteriological and clinical studies on cefozopran in neonates and premature infants. A study of cefozopran in the perinatal co-research group].

The following results were obtained in pharmacokinetic, bacteriological and clinical investigations of a cephem antibiotic for injection, cefozopran (SCE-2787, CZOP), administered to neonates and premature infants. 1. Pharmacokinetics (1) Half-lives (T 1/2's) of CZOP in 0-day-old (less than 24 hours after birth) neonates and premature infants were longer than those in 1-day-old or older infants. When half-lives were compared between 0-day-old neonates and 0-day-old premature infants, longer half-lives were observed in premature infants. (2) When CZOP was intravenously administered to 1-day-old or older neonates and premature infants at a dose of 20 mg/kg, no differences were noted in blood concentrations between neonates and premature infants from 30 minutes to 6 hours after administration as well as T 1/2's. (3) Blood concentration of CZOP administered at doses of 10, 20 and 40 mg/kg were dose-dependent. (4) Urine excretion rates of CZOP administered to 1-day-old or older neonates and premature infants were approximately 30 to 60% in the first 6 hours after administration. Urine excretion rates in 0-day-old neonates and premature infants were low. 2. Clinical results (1) Of a total of 136 cases to which CZOP was administered, clinical efficacy evaluation was possible in 96 cases, and safety evaluation in 132 cases. (2) The clinical efficacy rates were 78.6% (22/28) in 28 cases in which causative organisms were detected (Group A), and 97.1% (66/68) in 68 cases in which no such organisms were detected (Group B), with the total efficacy rate (Groups A and B) of as high as 91.7% (88/96). (3) Bacteriological evaluations were made with 33 strains isolated from the 28 cases of Group A. Elimination rates for Gram-positive and Gram-negative bacteria were 88.2% (15/17) and 92.3% (12/13), respectively, with the total elimination rate of 90.0% (27/30). No microbial substitution was noted. (4) As an adverse reaction, diarrhea was noted in one case (0.8%). Abnormal laboratory test values were noted in 15 cases (12.3%) including eosinophilia, elevated GPT, and elevated gamma-GTP. All of these abnormalities were transitory, and none of them critical. As a result of above pharmacokinetic and clinical investigations, CZOP is considered to be highly useful in the treatment of indicated infections in neonates and premature infants. It appears that 20 mg/kg of CZOP can be administered by intravenous injection or intravenous drip infusion to neonates and premature infants aged 0-day (less than 24 hours after birth) once or twice daily, to those aged 1 (24 or more hours after birth) to 7 days twice or three times daily, and to those aged 8 or more days three to four times daily, and that the dose can be increased up to 40 mg/kg in cases of critical or intractable infections.

Bacterial Infections↗
PubMed1996

Hepatocyte growth factor/scatter factor overexpression induces growth, abnormal development, and tumor formation in transgenic mouse livers.

To investigate the in vivo role of hepatocyte growth factor/scatter factor (HGF/SF) in liver function, we generated transgenic mice using a mouse HGF/SF cDNA under the control of the mouse metallothionein gene promoter and 5'/3' flanking sequences. In adult HGF/SF transgenic mice, liver weight as a percentage of total body weight was at least twice that of wild-type mice. Comparison of transgenic and control liver morphology revealed dramatic heterogeneity in the size and appearance of hepatocytes as a distinctive feature of HGF/SF overexpression. Transgenic livers exhibited a significant increase in the number of small hepatocytes with a 2N DNA content, accounting for the observed increase in liver mass. The DNA labeling index of hepatocytes increased 11-fold at 4 weeks of age, when liver enlargement first became apparent, and was still elevated about 5-fold in adult HGF/SF transgenic mice. Moreover, hepatocytes isolated by perfusion of transgenic livers doubled every 2 days in culture, whereas little or no growth was observed with isolated control hepatocytes. The mechanistic basis of hepatocyte proliferation was elucidated as the chronic activation of the c-met proto-oncogene product. Met and substrates such as phosphatidylinositol 3-kinase, Src homology and collagen-like, pp60c-src, focal adhesion kinase p125FAK, and paxillin were associated with tyrosine-phosphorylated complexes in a hepatocyte cell line established from the transgenic liver. This proliferative stimulus triggered the formation of hepatocellular adenomas and/or carcinomas in most transgenic mice > or = 1.5 years of age. Finally, the rate of transgenic mouse liver regeneration was increased 3-fold over control livers following partial hepatectomy.

Adaptor Proteins, Signal Transducing↗
PubMed1995

Keratinocyte growth factor.

Keratinocyte growth factor (KGF) is a member of the heparin-binding fibroblast growth factor family (FGF-7) with a distinctive pattern of target-cell specificity. Studies performed in cell culture suggested that KGF was mitogenically active only on epithelial cells, albeit from a variety of tissues. In contrast, KGF was produced solely by cells of mesenchymal origin, leading to the hypothesis that it might function as a paracrine mediator of mesenchymal-epithelial communication. Biochemical analysis and molecular cloning established that the KGF receptor (KGFR) was a tyrosine kinase isoform encoded by the fgfr-2 gene. Many detailed investigations of KGF and KGFR expression in whole tissue and cell lines largely substantiated the pattern initially perceived in vitro of mesenchymal and epithelial distribution, respectively. Moreover, functional assays in organ culture and in vivo and studies of KGF regulation by sex steroid hormones reinforced the idea that KGF acts predominantly on epithelial cells to elicit a variety of responses including proliferation, migration and morphogenesis.

Animals↗
PubMed1995

Epidermal growth factor enhances repair of rat intestinal mucosa damaged by oral administration of methotrexate.

To examine the trophic effect of epidermal growth factor on the rat small intestine, we measured diamine oxidase and ornithine decarboxylase activities in intestinal mucosa injured by methotrexate. Methotrexate was infused orally via a gastric tube at a dose of 10 mg/kg per day on 3 successive days (days 1-3). Epidermal growth factor was injected intraperitoneally at a dose of 40 micrograms/kg per day on 4 successive days following methotrexate infusion (days 4-7). Methotrexate caused a marked decrease in diamine oxidase activity; this decrease returned to a normal level on day 13 in controls. In rats injected with epidermal growth factor, diamine oxidase activity began to recover earlier than in the controls, and returned to a normal level on day 11. Epidermal growth factor enhanced the increase of ornithine decarboxylase activity in mucosa injured by methotrexate. When the increase of ornithine decarboxylase activity was suppressed by alpha-difluoromethylornithine, epidermal growth factor failed to facilitate the repair of intestinal mucosa. These results indicate that epidermal growth factor enhances intestinal repair following methotrexate infusion, and that this effect is mediated, at least in part, by ornithine decarboxylase. It is proposed that epidermal growth factor can be used clinically as a means to enhance mucosal repair of the intestine after chemotherapy with methotrexate.

Administration, Oral↗
PubMed1995

Case report of interferon alfa therapy for multiple myeloma during pregnancy.

Interferon alfa is broadly accepted as treatment for multiple myeloma, but its potential teratogenicity and mutagenicity during pregnancy in the human are still in dispute. We report a case of successful delivery after interferon alfa therapy for multiple myeloma during the first trimester of pregnancy. We reviewed the cases of interferon alfa treatment given during pregnancy for a malignancy and discovered that all of them have had successful deliveries and normal healthy babies. Additional studies should be encouraged to confirm the safety of interferon alfa therapy during pregnancy.

Adult↗
PubMed1995

Characterization of measles viruses isolated after measles vaccination.

Seven measles virus (MV) strains were isolated from children who developed clinical signs of fever and rash 3-9 days after measles vaccination. The nucleotide sequence of the H gene, the molecular size of the H protein, the haemadsorption activity on African green monkey red blood cells, and antigenicity as determined by virus neutralization revealed that one strain was of the vaccine type and the remaining six were the wild virus type. Isolation of the virus directly from patients suspected of a vaccine-induced side-reaction and subsequent characterization of such isolated virus may be useful in differentiation between vaccine-induced side-reactions and natural measles.

Antibodies, Monoclonal↗
PubMed1995

Prevention of recurrent bleeding from gastric ulcer with a nonbleeding visible vessel by endoscopic injection of absolute ethanol: a prospective, controlled trial.

We performed a prospective, randomized trial to assess the efficacy of endoscopic injection therapy with absolute ethanol in preventing recurrent bleeding in patients with nonbleeding visible vessels in gastric ulcers. During the period of 1990 to 1993, 62 patients who bled were found to have gastric ulcers with nonbleeding visible vessels; all of them were enrolled for this trial. The 62 patients were randomly divided into two groups, which were comparable at entry. In group I (33 patients), we performed endoscopic injection therapy with absolute ethanol. In group II (29 patients), we sprayed the ulcers with 0.1% epinephrine and thrombin. Endoscopic injection therapy with ethanol was performed at the second endoscopy in the patients in both groups who had recurrent bleeding. Among the 33 patients in group I, 4 patients (12.1%) rebled after the initial ethanol injection therapy, whereas 10 of 29 patients (34.5%) rebled in the control group (p < .05). No patients in group I required surgical intervention, and ultimate hemostasis was achieved in all 33 group I patients (100%), indicating that endoscopic ethanol injection therapy achieves ultimate hemostasis and prevents recurrent bleeding in patients with gastric ulcers and nonbleeding visible vessels.

Epinephrine↗