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M Yoshida

Publications and source records attributed to M Yoshida.

At least 487 records · Page 27Linked to original sources

[Different inhibiting effects of abciximab and tirofiban on platelet thrombus formation on a collagen surface under flow conditions].

OBJECTIVES: Recently developed anti-GPIIb/IIIa agents effectively inhibit acute thrombotic occlusion of coronary arteries after interventional treatment, and have similar inhibiting effects on plasma ligand binding to GPIIb/IIIa. Clinical investigation has revealed that abciximab, the chimeric monoclonal antibody against GPIIb/IIIa, has superior in vivo antithrombotic effects to other agents. The inhibiting effects of abciximab and another anti-GPIIb/IIIa agent, tirofiban, were investigated on platelet thrombus formation on a collagen surface under flow conditions. METHODS: Blood was drawn from 6 normal volunteers and anticoagulated with a specific inhibitor of thrombin, argatroban, at a final concentration of 100 microM. Platelets were rendered fluorescent by addition of mepacrine to a final concentration of 10 microM. Mepacrine is concentrated in the dense granules of platelets and leukocytes, but does not accumulate in red blood cells, so platelet thrombi can be detected by fluorescence microscopy even in the presence of red blood cells. Horizontal glass slips covered with fibrillar type I collagen were assembled in a Hele-Shaw type flow chamber. RESULTS: Platelet thrombi were developed on the collagen surface even in the absence of platelet activating agents. Both abciximab and tirofiban inhibited the platelet thrombus formation. Single platelet adhesion on the collagen surface was inhibited only by abciximab and not by tirofiban. CONCLUSIONS: The superior in vivo antithrombotic effects of abciximab may be partially explained by its inhibiting effects on the platelet adhesion on exposed subendothelial matrix.

Abciximab↗

[Impending paradoxical embolism visualized by echocardiography combined with pulmonary embolism: a case report].

A 43-year-old man was admitted to our hospital complaining of dyspnea on exertion and dizziness. Transthoracic echocardiography revealed a mobile mass (3.5 x 1.0 cm) attached to the left atrial septum and transesophageal echocardiography showed the mass in the right atrium protruding through the patent foramen ovale into the left atrium. A mobile snake-like thrombus was apparent in the right atrium and right ventricle. The diagnosis was pulmonary embolism with impending paradoxical emboli.

Adult↗

Plasma concentration of von Willebrand factor in acute myocardial infarction.

Recent investigations have revealed the crucial role of von Willebrand factor (vWF) in platelet thrombus formation under flow conditions. The plasma concentrations of vWF were measured together with various hemodynamic and hemostatic parameters in 51 cases of acute myocardial infarction. In 10 randomly selected cases, the plasma concentrations and distribution of multimers vWF were serially determined after reperfusion therapy by percutaneous transluminal coronary angioplasty (PTCA). The vWF concentration at the onset of the acute myocardial infarction was significantly higher than in an age-matched control group (vWF AG: 18.7 +/- 1.2 microg/ml vs. 10.3 +/- 0.5 microg/ml, p = 8.43 x 10-(12), mean +/- SE). Simultaneous determination of hemodynamic and hemostatic parameters revealed that the only two parameters that were significantly correlated with the patients' plasma vWF concentrations were their pulmonary capillary wedge pressure (PCWP) and heart rate, suggesting a relationship between hemodynamic changes induced by the onset of myocardial infarction and the vWF plasma concentrations. Serial determinations revealed that the vWF concentrations had not changed 1 h after reperfusion therapy, but that they significantly increased by 24 to 72 h. The distribution of the larger multimers of vWF also increased in the acute and subacute phase. The vWF concentration and multimer distribution normalized 14 days after the onset of the myocardial infarction. Our findings suggest that the vWF concentration increased in acute myocardial infarction patients, possibly in association with the hemodynamic deterioration that occurs in acute myocardial infarction.

Adult↗

[An autopsy case of corticobasal degeneration without prominent cortical pathology--an imitator of progressive supranuclear palsy].

We describe an autopsy case of parkinsonism with bradykinesia, muscle rigidity, and dementia as major symptoms. The patient had developed bradykinesia at the age of 62, and then muscle rigidity, a parkinsonian posture, bradylalia, and dementia gradually appeared. Neurological examination revealed rigidity in the neck and limbs, with motion and speech being generally slow. He lacked involuntary movements including alien hand, tremor, chorea, and dystonia. Vertical gaze palsy, both upward and downward was noted, but other cranial nerves were intact. He was diagnosed as suffering from PSP clinically based on vertical gaze palsy, bradykinesia, instability on standing and gait, and dementia. Levodopa was only transiently effective. Within three years he became bed-ridden and in a state of akinetic mutism. At age 65 he died from pneumonia. Neuropathology revealed severe neuronal degeneration and gliosis in the substantia nigra. Because atrophy of the tegmentum of brainstem, dentate nuclei, inferior olivary nuclei was very mild and Alzheimer neurofibrillary tangles in the brainstem were relatively few, PSP was ruled out. Cortical neuronal degeneration was not apparent, but in the deep layer of cingulate gyrus, frontal lobe, and insula, there were several ballooned neurons. Gallyas-Braak silver staining showed no tuft-shaped astrocytes, specific for PSP, but it disclosed astrocytic plaques in the basal ganglia and the cerebral cortex. At present, astrocytic plaques are recognized as a hallmark of corticobasal degeneration (CBD), along with ballooned neurons in the cerebral cortex. The present case thus illustrates that CBD has a wide spectrum and may include cases in which degeneration of cerebral cortex is very mild.

Aged↗

A case of probable acute interstitial pneumonia with a dramatic response to pulse corticosteroid administration.

A 38-year-old Japanese male without any significant respiratory risk factors was admitted to our hospital because of an acute onset of fulminant pneumonia refractory to intravenous antibiotics administration and an unexplained creatine kinase elevation. He was intubated and under ventilator support on the second hospital day, but responded dramatically to i.v. pulse methylprednisone treatment. After exclusion of secondary etiologies including collagen diseases, we concluded this case as a probable acute (idiopathic) interstitial pneumonia, or Hamman-Rich syndrome, responding dramatically to the corticosteroid pulse administration.

Acute Disease↗

[Treatment outcome in elderly patients with aggressive non-Hodgkin's lymphoma].

Seventy-one patients aged 61-84 years with previously untreated aggressive non-Hodgkin's lymphoma were treated with a doxorubicin-containing regimen and evaluated retrospectively. The patients comprised 49 men and 22 women with a median age of 68 years. The median observation period was 544 days. Histological examination revealed 17 cases of diffuse small cleaved, 11 cases of diffuse mixed, 40 cases of diffuse large, and 3 cases of immunoblastic lymphoma, classified according to the International Working Formulation. When the patients were divided according to the age-adjusted international index, group A (61-64 years; n = 21) comprised 5 low (L)-, 4 low-intermediate (LI)-, 7 high-intermediate (HI)-, and 5 high (H)-risk patients. The corresponding numbers in group B (> or = 65 years; n = 50) were 14, 12, 16, and 8, respectively. The overall three-year survival rate was 50%, being 78% in group A and 36% in group B (P = 0.02), and 77% for L + LI patients and 34% for HI + H patients (P = 0.003). The respective three-year survival rates for L + LI and HI + H patients were 100% and 67% in group A, and 68% and 16% in group B. HI + H patients in group B showed shorter survival than L + LI patients in group B (P = 0.002) and HI + H patients in group A (P = 0.03). The cause of death in most group B HI + H patients was lymphoma, although the dose intensity of doxorubicin, cyclophosphamide and vincristine did not differ significantly from that in the other groups. Thus, HI + H patients aged 65 and over had an essentially poor prognosis.

Aged↗

[Siblings with age-related macular degeneration in a pedigree].

BACKGROUND: The pathogenesis of age-related macular degeneration remains unknown. Environmental and genetic factors have been shown to be associated with in this disease. We report siblings with age-related macular degeneration. CASES: The proband (the third of 6 siblings) was found to have retinal pigment epithelial abnormalities and drusen of the right macula, and serous retinal detachment, drusen, and choroidal neovascularization of the left macula. Examination of the eldest siblings showed choroidal neovascularization, subretinal hemorrhage, and serous retinal detachment of the right macula. The left eye of the proband and the right eye of the eldest siblings were treated with laser photocoagulation. The fourth sibling was examined, and findings included retinal pigment epithelial abnormalities of both maculas and drusen of the right eye. The sixth sibling had drusen of the left macula. CONCLUSION: We report a family in which two siblings had age-related macular degeneration and two other siblings had abnormalities of the maculas.

Aged↗

Participation of pigment epithelium of iris and ciliary body in ocular immune privilege. 2. Generation of TGF-beta-producing regulatory T cells.

PURPOSE: To determine whether T cells exposed to cultured iris and ciliary body pigment epithelial (I/CB PE) cells acquire the capacity to modify the activation, differentiation, and effector functions of bystander T cells, and if so, to identify the mechanism. METHODS: T cells from naive BALB/c mice were cultured with I/CB PE cells, x-irradiated, and used as regulators (a) of T-cell activation in vitro and (b) of delayed hypersensitivity expression in vivo. Neutralizing anti-TGF-beta and -IL-10 antibodies were used to abolish regulatory function. T-cell activation was assessed for proliferation by [(3)H]thymidine incorporation and for IL-2, IFN-gamma, IL-4, and IL-10 production by semi-quantitative RT-PCR for mRNA and by supernatant analysis by ELISA. I/CB PE-exposed T cells were evaluated for mRNA content of IFN-gamma, IL-4, TNF-alpha, TGF-beta1, TGF-beta2, and IL-10, and their supernatants were analyzed for content of TGF-beta. RESULTS: T cells exposed to I/CB PE cells inhibited anti-CD3-driven activation of bystander naive T cells in vitro and suppressed the expression of delayed hypersensitivity in vivo. Bystander T cells cocultured with I/CB PE-exposed T cells failed to proliferate and secreted high levels of IL-4 and IL-10 but low amounts of IL-2 and IFN-gamma. Regulation of bystander T-cell activation was mediated via enhanced secretion of TGF-beta by I/CB PE-exposed T cells. CONCLUSIONS: T cells exposed to cultured I/CB PE cells were induced to secrete active and latent TGF-beta, which conferred on the T cells the capacity to inhibit the differentiation as well as the effector function of Th1-type cells.

Animals↗

Adenoviral transduction of human E-selectin into isolated, perfused, rat aortic segments: an ex vivo model for studying leukocyte-endothelial interactions.

E-selectin, a member of the selectin family of adhesion molecules, is thought to play an important role in leukocyte-endothelial (EC) interactions during inflammation and atherosclerosis. To critically examine the role of E-selectin in leukocyte-EC interactions in the vascular system, we created a recombinant adenoviral vector containing a human E-selectin cDNA (AdRSVE-sel) and examined the effect of AdRSVE-sel in an ex vivo vascular model of a rat aortic segment. A segment of abdominal aorta was isolated from a male Sprague-Dawley rat transduced with AdRSVE-sel ex vivo. After 72 h, surface expression of transduced E-selectin in the segment was confirmed by Western blotting and immunohistochemistry using anti-E-selectin mAb. Aortic segments were connected to a perfusion system and the adhesion of human polymorphonuclear neutrophils (PMN), and a human monocytic cell line (THP-1) to the EC surface was studied in the presence of a physiological level of flow (0.85 ml/min, approximate luminal surface shear stress=1.76 dyn/cm2). Adhesion of PMN was assessed by scanning electron microscopy and quantified using fluorescently labeled PMN. AdRSVE-sel transduced aortic segments mediated significantly more PMN and THP-1 adhesion than control segments transduced with AdRSVLacZ. Pretreatment of AdRSVE-sel transduced aortic segments with anti-E-selectin mAb inhibited PMN adhesion significantly, as well as THP-1. These data indicate that human E-selectin expressed in rat aortic segments can support the adhesion of human PMN as well as THP-1 under physiological flow conditions. This genetically modified, excised, vascular-segment model provides a useful tool for the study of leukocyte recruitment in the vascular system.

Adenoviridae↗

[Low back pain].

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Back↗

Specific distribution of TOP-53 to the lung and lung-localized tumor is determined by its interaction with phospholipids.

We have investigated the mechanism of TOP-53 distribution to the lung and lung-localized tumor. In contrast to etoposide (VP-16), TOP-53 contains a basic aminoalkyl group that may predispose it to interact specifically with phospholipids, consequently leading to an increase of drug accumulation in the tissues. Therefore, we have studied its interaction with phospholipids in vitro using an organic solvent-water partition system. TOP-53 appeared to have the most potent binding affinity (Ka = 563 x 10(-2) microM) to phosphatidylserine (PhS), whereas VP-16 showed no interaction with any phospholipid tested. PhS content determined after HPLC separation varied among tested tissues; however, large quantities were found in normal lung and lung cancer tissues far exceeding those present in the liver and kidney. The predicted tissue-to-plasma partition coefficient values, estimated based on PhS content and its binding affinity, resembled those experimentally determined. We concluded that tissue distribution of TOP-53 is determined by PhS content in the tissues and by binding affinity. As a result of specific accumulation in the lung, TOP-53 appeared to show a strong antitumor activity (increase of life span = 171%) against cancer metastasizing to the lung, whereas VP-16 was less effective (increase of life span = 78%). These results suggest that TOP-53 may have an advantage over VP-16 in the treatment of lung cancers in patients.

Animals↗

The role of cytokine-induced neutrophil chemoattractant-1 in neutrophil-mediated remote lung injury after intestinal ischaemia/reperfusion in rats.

OBJECTIVE: Remote lung injury is induced by ischaemia/reperfusion (I/R) of the gastrointestinal tract and the liver following hypovolaemic shock. In the present study, the role of cytokine-induced neutrophil chemoattractant (CINC), a member of the interleukin (IL)-8 family, in neutrophil-mediated remote lung injury following intestinal I/R was investigated in anaesthetized rats. METHODOLOGY: The I/R group was subjected to 60 min of occlusion of the superior mesenteric artery with laparotomy, followed by 240 min of intestinal reperfusion. The sham-operated (sham) group was subjected to the same procedures with the exception of intestinal I/R. RESULTS: In the I/R group, the permeability index of the lung, the neutrophil count in pulmonary vascular lavage fluid and bronchoalveolar lavage fluid (BALF), lung myeloperoxidase activity and neutrophil oxidative production were all significantly greater than those in the sham group. Cytokine-induced neutrophil chemoattractant-1 levels in blood and BALF were significantly increased at 240 min after intestinal reperfusion. There was a significant relationship between neutrophils in BALF and CINC-1 level in BALE CONCLUSION: These findings suggest that intestinal reperfusion was associated with activation and accumulation of neutrophils in the lung and resulted in remote lung injury with increased microvascular permeability. Thus, CINC-1 in BALF may induce neutrophil migration from the pulmonary vessels to the interstitium and alveolar spaces in remote lung injury after intestinal I/R.

Animals↗

[A case of latex allergy with bronchial asthma].

A 26-year-old nurse consulted our department because of shortness of breath, wheezing and skin eruption after eating lunch several days before. At the consultation, the symptoms had disappeared, pulmonary function showed no abnormality, and there were no abnormal findings on chest auscultation. Latex allergy was suspected because of a history of wheezing and skin eruption after wearing latex gloves and an elevated serum IgE level specific to latex antigen. After a usage test of medical latex gloves, wheezing, skin eruption, and a decrease of FEV1.0 on pulmonary function testing were observed. The case was therefore diagnosed as latex allergy with bronchial asthma. Her symptoms were not observed after polymer coated gloves were substituted. Latex allergy is apt to complicate food allergy, an initial symptom of the present case. Specific IgE for several kinds of food was also elevated.

Adult↗

Non-culture based diagnostic tests for mycotic infections.

Non-culture methods being developed and evaluated for mycotic infections include polymerase chain reaction (PCR), galactomannan (GM) antigenemia, Western blot (WB) to detect antibodies, and detection of the fungal metabolites D-arabinitol and (1,3)-beta-D-glucan. Sample preparation for PCR from blood specimens depends on fractionation of peripheral blood, its pre-incubation in blood culture broth, or a total DNA method, which does not rely on fractionation, or pre-incubation. Targets for PCR of fungi in the 18S or ITS2 subunits of the ribosomal RNA genes facilitated the design of Aspergillus and Candida genus and species probes. Amplicons were identified using PCR-enzyme linked immunosorbent assay (ELISA) or reverse line-blot formats. A pilot study indicated that PCR tests on blood specimens were positive at least once in patients with confirmed invasive aspergillosis (IA). When serum-PCR and serum-GM tests were compared in IA patients, antigenemia was more often positive. PCR detected Aspergillus DNA in bronchoalveolar lavage specimens from patients at risk even when cultures were negative. D-Arabinitol can be detected as a marker of candidiasis with gas chromatography-mass spectrometry or enzyme dependent-fluorometry. Each method can differentiate the microbial D- and host L-enantiomers. (1,3)-beta-D-Glucan is produced by most genera of pathogenic fungi and can be detected in plasma by the 'G-test'. In patients with febrile neutropenia the efficacy of azole therapy correlated with plasma (1,3)-beta-D-glucan concentrations of > or = 10 pg ml(-1). The diagnosis of early acute pulmonary histoplasmosis can be improved by a WB test utilizing deglycosylated M antigen, a 94-kDa glycoprotein. The identity of M antigen as a catalase was deduced from the sequence of the cloned gene. PCR identification of Histoplasma capsulatum cultures was accomplished with primer pairs selected from H and M antigen gene sequences.

Antibodies, Fungal↗

The gamma subunit in chloroplast F(1)-ATPase can rotate in a unidirectional and counter-clockwise manner.

Rotation of the gamma subunit in chloroplast F(1)-ATPase (CF(1)) was investigated by using a single molecule observation technique, which is developed by Noji et al. to observe the rotation of a central gamma subunit portion in the alpha(3)beta(3)gamma sub-complex of F(1)-ATPase from thermophilic Bacillus PS3 (TF(1)) during ATP hydrolysis [Noji, H. et al. (1997) Nature 386, 299-302]. We used two cysteines of the gamma subunit (Cys-199 and Cys-205) of CF(1)-ATPase, which are involved in the regulation of this enzyme, to fix the fluorochrome-labeled actin filament. Then we successfully observed a unidirectional, counter-clockwise rotation of the actin filament with the fluorescent microscope indicating the rotation of the gamma subunit in CF(1)-ATPase. We conclude that the rotation of the gamma subunit in the F(1)-motor is a ubiquitous phenomenon in all F(1)-ATPases in prokaryotes as well as in eukaryotes.

Actin Cytoskeleton↗