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Biomedical subjects

K Ogata

Publications and source records attributed to K Ogata.

At least 163 records · Page 9Linked to original sources
PubMed1997

[Interstitial pneumonia caused by manidipine HCl].

A 62-year-old woman was given a diagnosis of rheumatoid lung in 1993. She began receiving manidipine HCl (10 mg per day) on June 19, 1996 to treat hypertension. The next day fever, coughing and dyspnea developed. She was admitted to our hospital on June 28. A chest radiograph showed diffuse reticulo-nodular shadows in all lung fields and arterial blood gas analysis revealed severe hypoxemia. Administration of manidipine HCl was stopped and treatment with methylprednisolone was started. The symptoms and the radiographic evidence of infiltrates disappeared. A drug lymphocyte stimulation test for manidipine HCl was positive. We know of no previous report of pneumonia caused by manidipine HCl.

Antihypertensive Agents↗
PubMed1997

[Effect of controlled hypotension induced by prostaglandin E1 on evoked spinal cord potential and spinal cord blood flow].

We evaluated the effect of controlled hypotension induced by PGE1 on evoked spinal cord potential (ESCP) and spinal cord blood flow (SCBF) in 14 patients undergoing laminectomy or laminoplasty. They were divided into two groups: hypotensive group (group H), non-hypotensive group (group N). Controlled hypotension was induced with PGE1 to maintain mean arterial blood pressure at 55-60 mmHg for 45 min. The amplitude and latency of the N 1 potential were analyzed, and the SCBF was estimated by laser doppler flowmeter. There were no significant differences in ESCP and SCBF. These results suggest that controlled hypotension by PGE1 maintained normal local spinal cord blood flow autoregulation.

Aged↗
PubMed1997

Superoxide generation in neutrophils from hepatic vein in patients undergoing hepatectomy.

The present study was carried out to determine whether neutrophils could be activated to increase superoxide and myeloperoxidase production during liver surgery in clinical settings. We measured superoxide production in polymorphonuclear leukocytes (PMNs) obtained from the radial artery and hepatic vein during hepatectomy. We also determined plasma myeloperoxidase (MPO) as a marker of activation of the neutrophil. Blood samples were obtained from radial artery and from hepatic vein before operation and immediately after hepatectomy. Superoxide generation in PMNs from radial artery showed no significant change during hepatectomy, while oxidant generation in PMNs from hepatic vein increased after hepatectomy (from 40.5 +/- 4.20 to 44.8 +/- 4.80 nmol/10(6) cells/30 min; p < 0.05). MPO in the plasma obtained from hepatic vein also increased significantly after hepatectomy (from 166.6 +/- 23.0 to 225.4 +/- 26.2 micrograms/L; p < 0.05). The results show that neutrophils are activated locally in the liver for enhanced release of superoxide during hepatectomy, suggesting that these oxidant species may be involved in post hepatectomy liver damage.

Adult↗
PubMed1997

Current status of gnathostomiasis dorolesi in Miyazaki Prefecture, Japan.

Gnathostomiasis is an important food-borne parasitic zoonosis caused mainly by ingesting uncooked or undercooked flesh of freshwater fishes. Although four distinct species of the genus Gnathostoma were identified as the causative agents for human gnathostomiasis, human infections with G. doloresi have been found only in Japan, concentrated in Miyazaki Prefecture. So far we have found 25 cases in Miyazaki Prefecture. Although most of these patients were of cutaneous gnathostomiasis, two patients presented to the hospital with unusual clinical manifestations; one case was a pulmonary gnathostomiasis diagnosed by immunoserological methods, and the other was an ileus caused by migration of the late 3rd stage larva in the colonic tissue, which was found by post-operative histopathological examination. Although cutaneous lesions such as creeping eruption or mobile erythema are the common clinical features of gnathostomiasis, caution should be paid to the presence of such unusual cases.

Adult↗
PubMed1996

Cloning, sequencing and complementation analysis of the recA gene from Prevotella ruminicola.

Degenerate PCR primers based on conserved RecA protein regions were used to amplify a portion of recA [corrected] from Prevotella ruminicola strain 23, which was used as a probe to isolate the full-length recA gene from the P. ruminicola genomic library. The P. ruminicola recA gene encoded a protein of 340 amino acids with a molecular mass of 36.81 kDa, P. ruminicola RecA was highly similar to other RecA proteins and most closely resembled that of Bacteroides fragilis (75% identity). It alleviated the methyl methanesulfonate and mitomycin C sensitivities of Escherichia coli recA mutants, but did not restore the resistance to UV-light irradiation. Mitomycin C treatment of otherwise isogenic E. coli strains showed a higher level of prophage induction in a recA harboring lysogen.

Amino Acid Sequence↗
PubMed1996

Effects of age on levels of cysteine, glutathione and related enzyme activities in livers of mice and rats and an attempt to replenish hepatic glutathione level of mouse with cysteine derivatives.

There was a large statistically significant decrease in the hepatic level of cysteine and glutathione (GSH) in 24 month-old mice compared to young mice, while, cystine and glutathione disulfide (GSSG) contents in the liver did not differ between young and old mice. Activities of cystathionine gamma-lyase and beta-synthase in mouse liver of the 24 month-old group were significantly decreased. In rats, the hepatic levels of cysteine, cystine, GSH and GSSG exhibited no statistically significant change during aging to 30 month. As the rats matured, total hepatic activities of both cystathionine gamma-lyase and beta-synthase increased with maximum levels at 24 months of age and decreased to the same level found in 5 week old for the former and to 22% of that in 5 week old for the latter. Intraperitoneal administration of diethyl maleate to mice led to depletion of hepatic GSH. When N-acetylcysteine and a thiazolidine derivative were intravenously injected after diethyl maleate administration, the hepatic GSH level of mice was restored to the normal level.

Acetylcysteine↗
PubMed1996

Ipsilateral cortico-cortical inhibition of the motor cortex in various neurological disorders.

We used a paired-pulse magnetic stimulation technique to study ipsilateral cortico-cortical inhibition of the motor cortex in 48 patients with various neurological disorders and in 20 normal volunteers. In the normal subjects, the first subthreshold conditioning stimulus suppressed responses to the second suprathreshold test stimulus at interstimulus intervals (ISIs) of 1-5 ms (inhibition at short intervals), and facilitated them at ISIs of 8-15 ms (facilitation at long intervals). Patients with motor neuron disease, except those in whom brain stimulation produced control responses that were generated by direct activation of corticospinal neurons (D-waves), had normal inhibition at short intervals. Facilitation at long intervals was not elicited in some patients with amyotrophic lateral sclerosis. Less inhibition at short intervals and normal facilitation at long intervals was found for all the patients with progressive myoclonic epilepsy, a condition in which the excitability of cortical inhibitory interneurons is thought to be affected. Inhibition at short intervals was disturbed, but facilitation at long intervals was intact in the patients with movement disorders (Parkinson's disease, corticobasal degeneration, and Wilson's disease). In these patients, positron emission tomography (PET) studies showed decreased regional cerebral blood flow (rCBF) in the basal ganglia in the relaxed state. However, normal suppression was elicited in the patients with Parkinson's disease with normal rCBF. In four patients with chorea, the time-course of inhibition and facilitation was normal, even though PET studies showed decreased rCBF in the basal ganglia in two of them. Normal inhibition could not be elicited in patients who had a small lesion in the basal ganglia or in the pathway from basal ganglia to the primary motor cortex; the putamen, globus pallidus, and supplementary motor cortex. In contrast, patients who had a lesion in a sensory system (sensory cortex or sensory thalamus) or in the pontine nucleus had normal suppression. We conclude that the results of ipsilateral cortico-cortical inhibition with paired magnetic stimulation reflect the excitability of inhibitory interneurons in the motor cortex and that outputs from the basal ganglia markedly affect this inhibition, but outputs from somato-sensory systems or cerebellum do not. Moreover, dysfunction of the corticospinal tract or spinal motoneurons does not affect results obtained by the paired magnetic stimulation technique when the control responses are generated by I-waves (i.e. descending volleys are produced by transsynaptic activation of the corticospinal tract neurons.

Adult↗
PubMed1996

Spermine suppresses the activation of human neutrophil NADPH oxidase in cell-free and semi-recombinant systems.

Spermine, a cellular polyamine, down-regulates O2- generation in human neutrophils stimulated by receptor-linked agonist [Ogata, Tamura and Takeshita (1992) Biochem. Biophys. Res. Commun. 182, 20-26]. In this study, to elucidate the mechanism for the inhibition, the effect of spermine on cell-free activation of the O2- generating enzyme (NADPH oxidase) was examined. Spermine suppressed the SDS-induced activation of NADPH oxidase in a dose-dependent manner with an IC50 of 18 microM. The inhibition was specific for spermine over its precursor amines, spermidine and putrescine. Spermine did not alter the Km for NADPH or the optimal concentration of SDS for activation. The amine was inhibitory only when added before activation, indicating that it affects the activation process rather than the enzyme's activity. An increased concentration of cytosol partly prevented the inhibition by spermine. In semi-recombinant cell-free system, spermine inhibited the activation of NADPH oxidase as effectively as in the cell-free system (IC50 = 13 microM). Pretreatment of each recombinant cytosolic component with spermine revealed that they (especially p67phox) are sensitive to spermine. These results suggest that spermine interacts with cytosolic component(s) and impairs the assembly of NADPH oxidase.

Cell-Free System↗
PubMed1996

Structural organization of pRAM4, a cryptic plasmid from Prevotella ruminicola.

A total of 530 strains of rumen bacteria were screened for the presence of plasmid DNA. The percentage of plasmid-bearing strains was found to be the highest among the Bacteroides/ Prevotella group (9.9%), while it was less than 1% in the Butyrivibrio (0.2%) and Clostridium (0.6%) genera. A small cryptic plasmid pRAM4 from Prevotella ruminicola T31 was subcloned in Escherichia coli and completely sequenced. Two open reading frames, encoding potential polypeptides of M(r) 32,322 (ORF1) and 32,122 (ORF2) with limited sequence similarity to replication initiation and mobilization proteins, respectively, could be identified within the sequence. The region upstream from ORF1 had an AT-rich (75%) region followed by four 22-bp direct repeats, a structure characteristic of replication origins. The plasmid hybridized at high stringency with plasmids from Bacteroides/Prevotella and Butyrivibrio, and with pBR322, suggesting that at least regions of the plasmid are widespread.

Amino Acid Sequence↗
PubMed1996

Autoimmune hemolytic anemia in patients with de novo acute myelocytic leukemia.

Autoantibody against erythrocytes has occasionally been observed in patients with de novo acute myelocytic leukemia (AML). However, it is not clear whether this autoantibody in AML patients induces frank hemolysis (autoimmune hemolytic anemia, AIHA), as seen in lymphoid neoplasms. We present two de novo AML patients who showed hemolysis due to antiglobulin test-positive and test-negative AIHA, respectively. AIHA should be considered as one cause of anemia in de novo AML patients, and blood transfusions should be given carefully in such cases to avoid harmful hemolysis.

Adult↗
PubMed1996

Effect of CNTF on ischaemic cell damage in rat hippocampus.

The neuroprotective effect of neurotrophic factors has been demonstrated in experimental cerebral ischaemia recently. These include nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1), and basic fibroblast growth factor (basic FGF). The neuroprotective effect of ciliary neurotrophic factor (CNTF), however, has not been studied so far. We have examined the neuroprotective effect of recombinant rat CNTF in a rat forebrain ischaemia model. A continuous infusion of CNTF was started 1 week before the induction of ischaemia and continued until 1 week after the ischaemia. Reversible forebrain ischaemia was induced by 7 minutes of bilateral carotid occlusion with hypotension. Neuronal cell death in the hippocampal CA1 sector was evaluated 1 week after the ischaemia. For the control group artificial CSF (cerebrospinal fluid) was infused instead of CNTF. Per cent neuronal cell death was 83.4 +/- 5.9% (mean +/- SEM, n = 5) in the control group, and 71.1 +/- 10.0% (mean +/- SEM, n = 5) in the CNTF group. Although percentage of neuronal cell death was lower in the CNTF group, the difference was not statistically significant. This result suggests that the protective effect of CNTF in the rat forebrain ischaemia model may be limited compared with other neurotrophic factors. It is considered that the number of neurons protected by CNTF may be small.

Animals↗
PubMed1996

Quantitative bone scanning of the hip. Comparison between the perfusion and static phases.

Quantitative bone scanning of the hip was carried out in 50 patients, 45 with unilateral disorders, and 5 with no symptoms and normal radiographs. The uptake ratio of the involved femoral head was calculated in the perfusion and static phases. In the patients with no symptoms the difference in the uptake ratio between the right and left hips averaged less than 0.02 in both phases. In 5 patients with a unilateral endoprosthesis the average was 0.52 in the perfusion and 0.34 in the static phase. In 10 patients with intertrochanteric fractures, 9 with undisplaced femoral neck fractures and 7 with osteoarthritis, each uptake ratio averaged more than 1.1 in both phases. In 9 patients with displaced femoral neck fractures, the mean ratio was 0.76 in the perfusion and 0.92 in the static phase. In 5 patients with avascular necrosis the ratio was 0.82 in the perfusion and 1.57 in the static phase. Quantification of uptake in both phases provides objective data reflecting bone blood flow and metabolism in various disorders of the hip.

Adult↗
PubMed1996

Short arm of chromosome 1 aberration recurrently found in pigmented villonodular synovitis.

Pigmented villonodular synovitis (PVNS) is a relatively uncommon benign lesion that is characterized by diffuse synovial proliferation, mainly occurring in knee joints. Cytogenetic reports about this lesion are few and they describe the presence of numerical and structural chromosome aberrations. We obtained PVNS tissue from the left knee joint of a 53-year-old female, and performed cytogenetic analysis. Fluorescence in situ hybridization (FISH) was also performed by using the formalin fixed, paraffin embedded PVNS tissue. Two seemingly unrelated clones were found: the first clone had structural abnormalities of chromosome 1, 3, and 18, and the second one had trisomy 7 as a sole numerical abnormality. FISH using a chromosome 7 specific alpha-satellite DNA probe revealed that interphase nuclei possessed two or three signals. We describe the clonal aberrations found in a case of PVNS. The deleted lesion of the chromosome 1 (1p10-1p31.3) includes the locus of coagulation factor III gene (1p22-p21), and the coagulation factor V (1q21-q25) locus includes another breakpoint that is 1q25. In addition, recurrent structural abnormalities at the short arm of chromosome 1 have been reported. These facts might play some role in the hemorrhagic tendency and histogenesis of these lesions.

Chromosome Aberrations↗
PubMed1996

Effects of hemodilution during controlled hypotension of hepatic, renal, and pancreatic function in humans.

STUDY OBJECTIVE: To evaluate the effects of hemodilution during controlled hypotension on, the hepatic renal, and pancreatic function in the clinical setting. DESIGN: Randomized, prospective study. SETTING: Inpatient surgery at Rosai Hospital. PATIENTS: 20 ASN status I and II patients scheduled for total hip arthroplasty. INTERVENTIONS: Hemodilution was carried out after induction of anesthesia, in which drawn blood was replaced with dextran solution to achieve final hematocrit (Hct) of 31% Group A = mild hemodilution group, N = 10) or 23% (Group B = moderate hemodilution group, N = 10). In both groups, controlled hypotension was induced with prostaglandin in (PGE1) to maintain mean arterial blood pressure at 55 mm Hg for 80 minutes. MEASUREMENTS AND MAIN RESULTS: Measurements included arterial ketone body ratio AKBR, aceto-acetate/3-hydroxybutyrate) for hepatic cellular function, pancreatic phospholipase A2 (P-PLA2) for pancreatic cellular function, and urine N-acetyl-beta-D-glucosaminidase (NAG index) for cellular function of the renal tubule. These indices were measured before hemodilution, after hemodilution, 80 minutes after starting hypotension, 60 minutes after recovery of normotension, and on the first postoperative day. Neither AKBR nor P-PLA2 showed a significant change throughout the time course of the study in either group. Urine-NAG index showed a significant increase in moderate hemodilution group at 60 minutes after recovery of normotension (+ 136%) and on the first postoperative lay (+ 149%) compared with prehemodilution value, whereas it showed no significant change in the mild hemodilution group. Blood urea nitrogen and serum creatinine measured postoperatively were within normal range. CONCLUSIONS: PGE1 induced hypotension combined with moderate hemodilution using dextran, such as 23% of Net value maintains hepatic and pancreatic function but causes damage to the renal tubular cells.

3-Hydroxybutyric Acid↗
PubMed1996

The cavity in the hydrophobic core of Myb DNA-binding domain is reserved for DNA recognition and trans-activation.

The DNA-binding domain of Myb consists of three imperfect repeats, R1, R2 and R3, each containing a helix-turn-helix motif variation. Among these repeats, R2 has distinct characteristics with high thermal instability. The NMR structure analysis found a cavity inside the hydrophobic core of R2 but not in R1 or R3. Here, we show that R2 has slow conformational fluctuations, and that a cavity-filling mutation which stabilizes the R2 structure significantly reduces specific Myb DNA-binding activity and trans-activation. Structural observations of the free and DNA-complexed stages suggest that the implied inherent conformational flexibility of R2, associated with the presence of the cavity, could be important for DNA recognition by Myb.

Amino Acid Sequence↗
PubMed1996

Plasma soluble interleukin-2 receptor level in patients with primary myelodysplastic syndromes: a relationship with disease subtype and clinical outcome.

To assess the hypothesis that the plasma soluble interleukin-2 receptor (sIL-2R) level may have predictive value for morbidity/mortality in patients with myelodysplastic syndromes (MDS), we determined in plasma sIL-2R level of 80 MDS patients and examined their subsequent clinical course. Compared with low-risk MDS (refractory anaemia (RA) and RA with ringed sideroblasts) patients and normal subjects, the plasma sIL-2R level was significantly elevated in high-risk MDS (three other MDS subtypes and acute leukaemia following MDS) patients (high-risk MDS versus low-risk MDS, P < 0.01; high-risk MDS versus normal subjects, P < 0.01). 14/40 low-risk MDS patients developed at least one of the following during the follow-up period: erythrocyte transfusion dependence, infections requiring hospitalization, disease progression or MDS-related death. The plasma sIL-2R level was higher in these eventful subjects than in event-free low-risk subjects (P < 0.0001), and all of 10 low-risk subjects with a plasma sIL-2R level > 540 U/ml experience at least one event. By logistic regression analysis of various parameters in these 40 low-risk subjects, the plasma sIL-2R level was identified as the strongest independent parameter for predicting eventful subjects (P < 0.0047). The plasma sIL-2R level did not show a predictive value in high-risk MDS. This study revealed that the plasma sIL-2R level is significantly elevated in high-risk MDS and suggested that the plasma sIL-2R level is a valuable predictive factors for the clinical outcome in low-risk MDS.

Adult↗