Reduced erythrocyte complement receptor type 1 in autoimmune thrombocytopenic purpura.
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Aged↗
Biomedical subjects
K Sakai
Publications and source records attributed to K Sakai.
Myxoid leiomyosarcoma of the kidney accompanying ipsilateral ureteral transitional cell carcinoma. A case report with cytological, immunohistochemical and ultrastructural study.
The authors report a case of myxoid leiomyosarcoma of the kidney accompanying ipsilateral ureteral transitional cell carcinoma. A 74-year-old male patient complained of turbid urine and macroscopic hematuria. He also complained of left back pain, appetite loss and weight loss. Computed tomography revealed a large mass in the left retroperitoneum. Urine cytology disclosed two types of malignant cells, atypical spindle-shaped cells and transitional cell carcinoma. Left total nephro-ureterectomy was performed. The left kidney was occupied by a 6 x 4 x 4 cm, multinodular and mucinous tumor. A transitional cell carcinoma of the left ureter was also observed. The renal tumor was composed of atypical spindle-shaped cells in the mucinous stroma, which showed positive immunoreactivity for anti-muscle-specific actin and anti-desmin antibodies. The ultrastructural examination revealed intracytoplasmic microfilaments with dense bodies, pinocytotic vesicles and junctional structure. These findings were suggestive of the myogenic feature of the case. Urine cytology revealed a number of sarcoma cells in this case since the sarcoma cells markedly invaded the renal pelvis and were apt to separate individually in myxoid stroma. Simultaneous and ipsilateral double malignancies of the renal sarcoma and ureteral transitional cell carcinoma have never been reported in the literature.
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Characterization of delta-sleep-inducing peptide-evoked release of Met-enkephalin from brain synaptosomes in rats.
Delta-sleep-inducing peptide (DSIP) stimulates the release of Met-enkephalin (Met-ENK) from superfused slices of the rodent lower brainstem in vitro. In our present study, DSIP (10(-10)-10(-9) M) induced a significant release of Met-ENK from medullary synaptosomes of rats. This DSIP-evoked release of Met-ENK was Ca2+ dependent and tetrodotoxin (TTX) insensitive. Furthermore, DSIP (10(-11)-10(-9) M) significantly increased 45Ca2+ uptake in medullary synaptosomes. These results demonstrate that DSIP acts directly on the nerve endings of Met-ENK-containing neurons to release this pentapeptide by generating a Ca2+ influx into these neurons. Effects of DSIP on Met-ENK release in other discrete brain regions were also studied. Significant DSIP-evoked Met-ENK release from synaptosomes was observed in the cortex, hypothalamus, and midbrain (at concentrations of 10(-10) and 10(-9) M) and in the hippocampus and thalamus (only at 10(-9) M), but not in the striatum. In the hypothalamus, the release of Leu-enkephalin from its synaptosomes was slightly, but not significantly, enhanced by DSIP (10(-10)-10(-8) M). Our findings demonstrate that DSIP triggered a Ca2+ influx in nerve endings to induce a subsequent release of Met-ENK from neurons in only certain brain regions.
Animals↗
Production and characterization of N-acyl-D-glutamate amidohydrolase from Pseudomonas sp. strain 5f-1.
N-Acyl-D-glutamate amidohydrolase from Pseudomonas sp. strain 5f-1 was inducibly produced by D isomers of N-acetylglutamate, glutamate, aspartate, and asparagine. The enzyme has been purified to homogeneity by DEAE-cellulose, (NH4)2SO4 fractionation, and chromatofocusing followed by gel filtration on a Sephadex G-100 column. The enzyme was a monomer with molecular weight of 55,000. The enzyme activity was optimal at pH 6.5 to 7.5 and 45 degrees C. The isoelectric point and the pH stability were 8.8 and 9.0, respectively. N-Formyl, N-acetyl, N-butyryl, N-propionyl, N-chloroacetyl derivatives of D-glutamate and glycyl-D-glutamate were substrates for the enzyme. At pH 6.5 in 100 mM N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) buffer at 30 degrees C, a Km of 6.67 mM and a Vmax of 662 mumol/min/mg of protein for N-acetyl-D-glutamate were obtained. None of the metal ions stimulated the enzyme activity. Na+, K+, Mg2+, and Ba2+ acted as stabilizers. Hg2+, Cu2+, Zn2+, Fe3+, and EDTA were strongly inhibitory.
Amidohydrolases↗
Recombinational analysis of a natural noncytopathic human immunodeficiency virus type 1 (HIV-1) isolate: role of the vif gene in HIV-1 infection kinetics and cytopathicity.
Two molecularly cloned coisolates of human immunodeficiency virus type 1 (HIV-1) have been found to exhibit different phenotypes of viral expression, either rapid and cytopathic (N1T-A virus) or delayed and noncytopathic (N1T-E virus [X. Ma, K. Sakai, F. Sinangil, E. Golub, and D. J. Volsky, Virology 176:184-194, 1990]). To identify the viral genetic elements responsible for these phenotypes, we prepared reciprocal recombinants in different regions of N1T-A and N1T-E viral genomes. Infectivity experiments with the recombinant viruses revealed that the rapid/cytopathic (N1T-A-like) phenotype assorted cleanly with the V1f-coding region and Vif expression. The smallest HIV-1 DNA region that conferred the complete phenotypic switch was a 284-bp NdeI-StuI fragment within the vif open reading frame. Nucleotide sequence analysis revealed a 35-bp deletion starting at nucleotide 218 in the N1T-E vif gene. A 23-kDa Vif protein was detected by immunoblotting using Vif-specific antiserum in extracts of cells infected with N1T-A but not N1T-E virus. No detectable vif protein was found in association with sedimented particles of either virus. Cotransfection of a eucaryotic vif expression plasmid with N1T-E DNA complemented the N1T-E defect; rapid/cytopathic infection similar to that in N1T-A-transfected cells was observed. We conclude that Vif controls the rate, and consequently the cytopathic outcome, of HIV-1 infection.
Amino Acid Sequence↗
Renal involvement in POEMS syndrome.
We describe a patient with POEMS syndrome whose renal biopsy specimen also showed nephropathy. Immunoelectron microscopy of the renal biopsy revealed the localization of immunoglobulin (IgA and lambda light chain) in the subendothelial space of the glomerular capillaries, a previously unrecognized finding. We conclude that the renal pathology in POEMS syndrome is unusual and distinct from microangiopathic glomerular involvement or idiopathic mesangiocapillary glomerulonephritis.
Adult↗
Effects of dietary oils with extreme omega 3/omega 6 ratios--selective incorporation and differential catabolism.
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Animals↗
Surface-modulated skin layers of thermal responsive hydrogels as on-off switches: I. Drug release.
Thermosensitive co-polymers of isopropyl acrylamide (IPAAm) with butyl methacrylate (BMA) are capable of 'on-off' regulation of drug release in response to external temperature changes due to skin formation with increasing temperature. To clarify the role of the surface-modulated skin and controlled pulsatile drug release patterns, the surface shrinking process was regulated by changing the length of the methacrylate alkyl side-chain. Release of indomethacin in response to stepwise temperature changes between 20 and 30 degrees C from co-polymers of IPAAm with BMA, hexyl methacrylate (HMA), and lauryl methacrylate (LMA) was studied. The drug release rate during the 'on' state (20 degrees C) remained constant before and after the 'off' state (30 degrees C) when the period of the 'off' state was increased. These results suggest that the drug in the polymeric matrices diffused from the inside to the surface during the 'off' state even when no drug release was seen. The length of alkyl side-chain was found to be an important parameter in controlling the thickness and density of the surface skin layer.
Cross-Linking Reagents↗
A putative mouse oocyte maturation inhibitory protein from urine of pregnant women: N-terminal sequence homology with human nonsecretory ribonuclease.
A putative mouse oocyte maturation inhibitory protein was purified from a urine preparation from pregnant women by Sephadex G-100 gel filtration and reverse-phase chromatography on the basis of inhibitory activity of polar body formation of denuded mouse oocytes in culture. Amino terminal sequence analyses showed that residues 5 to 15 of this protein were identical to residues 1 to 11 of human nonsecretory ribonuclease. Furthermore, residues 1 to 4 of this protein were identical to residues -4 to -1, corresponding to part of a signal peptide region of eosinophil-derived neurotoxin, whose mature sequence is identical to nonsecretory ribonuclease. These results indicate that the protein purified as a putative mouse oocyte maturation inhibitory protein from the urine of pregnant women may be a product of an peculiar processing of a nonsecretory ribonuclease precursor.
Amino Acid Sequence↗
Effects of a high alpha-linolenate and high linoleate diet on hemolysis and lipid peroxidation of rat erythrocytes.
alpha-Linolenic acid (18:3n-3) is known to autoxidize several fold faster than linoleic acid (18:2n-6). Feeding a high alpha-linolenate or a high linoleate diet to rats resulted in significant changes in the n-3/n-6 ratios of 20 and 22 carbon highly unsaturated fatty acids in erythrocytes. However, the rates of hemolysis observed in N2- or O2-atmosphere were similar between the two dietary groups. No significant amounts of conjugated dienes were detected and no measurable changes in the fatty acid compositions were observed during the incubations, indicating that the hemolysis occurred without involving significant lipid peroxidation. When stimulated with a free radical initiator, [2,2'-azobis-(2-amidinopropane)dihydrochloride] (AAPH), hemolysis occurred more rapidly, conjugated dienes formed and unsaturated/saturated ratios of phospholipid fatty acids decreased. However, no statistically significant difference was observed in these parameters of the two dietary groups. These results indicate that hemolysis occurs without involving lipid peroxidation but is accelerated by free radicals through lipid peroxidation, and that the difference in autoxidizabilities of alpha-linolenate and linoleate is not reflected in the rates of hemolysis and autoxidation in rat erythrocytes.
Animals↗
[Pharmacological effects of the novel dopamine uptake inhibitor 1-[2-[bis(4-fluorophenyl)-methoxy]ethyl]-4-(3-phenylpropyl) piperazine dihydrochloride (I-893) on the central nervous system].
The effects of 1-[2-[bis (4-fluorophenyl)methoxy]ethyl]-4-(3- phenylpropyl) piperazine dihydrochloride (I-893) on the central nervous system were behaviorally and electroencephalographically investigated. Intraperitoneally injected I-893 (5-10 mg/kg) dose-dependently increased spontaneous motor activity in mice, but repeated injections did not affect the increase in the locomotor activity. In reserpinized mice, spontaneous motor activity was not increased by oral I-893. In alpha-MPT-treated mice, the motor activity was lower than that in vehicle-treated animals with intermediate doses (10-40 mg/kg, p.o.) of I-893, but there was no difference between the two groups with high doses. In rats with unilaterally 6-OHDA-induced lesion of the nigrostriatal pathway, I-893 induced circling behavior toward the lesioned side. Haloperidol-induced catalepsy in rats was reduced by I-893. Tremorine-induced tremor in mice was inhibited by I-893. The effect was not altered in the mice treated with I-893 for 10 days. Oral I-893 induced stereotypy in rats, but it did not affect methamphetamine-induced stereotypy. Hypnosis induced by barbiturates was antagonized by I-893. In rats treated with I-893 for 6 days, pentobarbital-induced sleep was not different from that in vehicle-treated animals on the day after the final treatment. Intravenous I-893 altered EEGs in the cerebral cortex and amygdala nucleus to low voltage and fast waves and altered hippocampal EEG to theta waves in immobilized rabbits. These results suggest that I-893 inhibits re-uptake of dopamine released by exocytosis and indirectly has dopaminergic effects.
Animals↗
Unusual spontaneous entrapment of a dissecting aneurysm of the vertebral artery--case report.
The authors report a case of subarachnoid hemorrhage due to spontaneous dissection of the intracranial segment of the left vertebral artery. Serial angiography demonstrated spontaneous entrapment of the lesion 4 months after ictus.
Aortic Dissection↗
Regulatory mechanisms for the expression of a functional beta chain of interleukin 2 receptor on T4 chronic lymphocytic leukemia cells.
Monoclonal antibodies, each recognizing interleukin 2 receptor (IL-2R) alpha, or beta, were used to see the regulatory mechanisms of the expressions on leukemic cells from a patient with T4 chronic lymphocytic leukemia (T4-CLL). Cells from this patient expressed only IL-2R beta, and the expression was enhanced by medium cultivation. IL-1 enhanced the expression of not only IL-2R beta but also IL-2R alpha on the cells. Binding studies using 125I-IL-2 showed the presence of an intermediate receptor (734 sites/cell, Kd = 1.2 nM) and a few high-affinity receptor (172 sites/cell, Kd = 132 pM) on cells cultured with IL-1. IL-2 and IL-1 synergistically promoted the proliferation of the cells, suggesting that the induced IL-2R was functional. In addition, anti-IL-1 antibodies inhibited IL-2R beta expression by cultured cells, suggesting that it was dependent on IL-1 produced by the leukemic cells. These findings suggested that IL-1 might enhance the expression of IL-2R beta in a subset of human T cells, and implied a role of IL-1 in the proliferation of the leukemic T cells.
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[The effect of pyeloplasty on renal function in children with unilateral ureteropelvic junction obstruction. Investigation of the split renal function using DMSA renal uptake rate].
Pre- and post-operative changes of renal function in twenty children (10 were younger than 2 years old) with unilateral hydronephrosis due to ureteropelvic junction obstruction were studied on the basis of DMSA renal uptake rate. A marked increase in DMSA renal uptake rate was observed in thirteen cases (65%) after pyeloplasty on the obstructed side. Among them eight children were younger than 2 years old. In 6 children younger than 2 years old, a remarkable increase of DMSA renal uptake rate after reconstructive operation was recognized not only on the obstructed side but also on the contralateral normal side. These tendency could not be observed in those older than 2 years old. These results suggest that, in the young children, the obstructed kidney inhibits the contralateral normal and compensatory renal growth, and that the relief of obstruction eliminates this inhibition and causes the renal growth spur in a normal kidney. We conclude that it is essential to correct unilateral ureteropelvic junction obstruction before two years of age if an improvement of renal function not only on the obstructed side but also on the normal side is to be expected.
Adolescent↗
Pannorin, a new 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor produced by Chrysosporium pannorum.
Pannorin, a naphthopyrone that inhibits 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in cholesterol synthesis, was isolated from a culture broth of Chrysosporium pannorum M10539 by solvent extraction, Bio-Gel P-6 column chromatography and reverse phase HPLC (Silica ODS). Spectroscopic analyses of the compound yielded 4,8,10-trihydroxy-5-methyl-2H-naphtho[1,2-b]pyran-2-one as the proposed structure. Pannorin inhibited HMG-CoA reductase and in vitro sterol synthesis 50% at a concentration of 160 microM.
Animals↗
[Surgical management of congenitally corrected transposition of the great arteries].
From 1962 to 1990, we have experienced 12 patients with congenitally corrected transposition of the great arteries (CTGA). Associated cardiac defects were present in all cases, most frequently ventricular septal defect (100%), and pulmonary stenosis (67%), Palliative procedures were done in 5, corrective operations in 6. One patient underwent corrective procedure 27 years after palliation. The hospital mortality rate was 8% (1/12), and 1 late death (8%) was seen in this series. In most cases, we approached the defect through the mitral valve, and the deLeval method was very useful in placing stitches along the trabecular septum. AV conduction disturbance could be avoided in 5 of 6 patients who underwent the closure of ventricular septal defect. Pulmonary stenosis was relieved by valvotomy and/or infundibulectomy, or implantation of an extracardiac conduit according to their anatomy. Cardiac function of systemic ventricle (morphologic right ventricle) were well preserved in the case undergoing intracardiac repair and also in the palliative cases. Careful observation is needed in these cases.
Adolescent↗
[The effect of a new immunosuppressive agent, FK-506, on xenogeneic neural transplantation in rodents--comparison with cyclosporin A].
The present study was performed to compare the immunosuppressive effect of FK-506 (FK) with cyclosporin A (CyA) in xenogeneic neural transplantation in rodents. The solid grafts of embryonic ventral mesencephalic tissue from 14-day rat embryos were transplanted into the right lateral ventricle of 20 mature male mice using a stereotactic approach, and the mice were sacrificed 14 days after transplantation. The removed brains, which were sectioned coronally, were stained with antibodies against glial fibrillary acidic protein (GFAP), Lyt-2 or tyrosine hydroxylase (TH) in addition to hematoxylin-eosin and Nissl stainings. The subcutaneous (s.c.) administration of FK at a dose of 10.0 mg/kg daily for 14 days enabled the neural xenografts to survive and grow (n = 5), although all of the neural xenografts treated with CyA at a dose of 10.0 mg/kg s.c. (n = 5) or FK at a dose of 1.0 mg/kg s.c. (n = 5) daily for 14 days and ones treated without such an immunosuppressive agent (n = 5) were rejected by immunological reactions. We conclude that FK is a more powerful immunosuppressive agent than CyA in xenogeneic neural transplantation as well as in cardiac and renal allograftings.
Animals↗
[Generalized choreic movement associated with subarachnoid hemorrhage].
A case of generalized choreic movement associated with subarachnoid hemorrhage is reported. A 71 year-old hypertensive woman suddenly developed severe headache 14 days before admission. Consciousness disturbance and involuntary movement involving the face and upper extremities appeared about 8 days after onset. The involuntary motion was diagnosed as generalized choreic movement. CT scans showed subarachnoid hemorrhage with ventricular dilatation and periventricular lucency involving bilateral caudate nuclei. On admission the patient was stuporous with Hunt & Kosnik Grade 4. She showed involuntary choreic movement in both arms, trunk and face; hemiparenis and hyperreflexia were absent. An angiography revealed a right internal carotid-anterior choroidal artery aneurysm with vasospasm. After clipping the aneurysm in the following day, the consciousness disturbance and choreic movement gradually improved. By eight days after operation, the choreic movement completely disappeared. An MRI showed lacunar infarcts in the bilateral basal ganglia, predominantly in the caudate nuclei. In our case, the choreic movement is supposed to have been caused by impaired circulation in the bilateral corpora striata due to vasospasm and hydrocephalus after subarachnoid hemorrhage, in addition to the preexisting lacunar infarcts in the basal ganglia. This is claimed to be the first reported case of generalized choreic movement in associated with subarachnoid hemorrhage, which improved after surgery.
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