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1.
We studied the effects of hemoglobin-vesicles modified with PEG (PEG-HbV), a type of liposome-encapsulated hemoglobin (LEH), on human platelet functions in vitro. The effect of a low concentration of PEG-HbV (Hb; 5.8 mg/dl) was assessed by examining an agonist-induced aggregation response, and that of relatively high concentrations of PEG-HbV (Hb; 0.29, 1 and 2 g/dl) by measuring the release of RANTES (Regulated upon activation, normal T-cell expressed and presumably secreted) from platelets, which is regarded as a marker of platelet activation. The preincubation of platelets with PEG-HbV at 5.8 mg/dl of Hb did not affect platelet aggregation induced by collagen, thrombin and ristocetin. The pretreatment of platelet-rich plasma (PRP) with PEG-HbV at concen trations up to 2 g/dl of Hb had no aberrant effects on the collagen-induced RANTES release. Furthermore, the collagen-induced release of RANTES from PRP was not affected by longer incubation with PEG-HbV at 2 g/dl of Hb. The basal levels of RANTES from PRP were unchanged in the presence of PEG-HbV. These results suggest that PEG-HbV, at the concentrations studied, have no aberrant effects on platelet functions in the presence of plasma.  相似文献   
2.
A 78-year-old male who had a bronchial asthma underwent coronary artery bypass grafting (CABG) using the left internal thoracic artery and the radial artery. The patient could not be weaned from the cardiopulmonary bypass because the radial artery which anastomosed to the obtuse marginal artery (OM) had a spasm after CABG. An additional bypass using a long saphenous vein to OM was carried out immediately. It brought a weaning from cardiopulmonary bypass. If the cardiac function after CABG is insufficient in patients with bronchial asthma, CABG must be re-done immediately, considering that they cause the arterial spasm more than patients without bronchial asthma.  相似文献   
3.
Social skill deficits in schizophrenia profoundly affect patients' life-long outcome, although the profile of the underlying cognitive dysfunction still remains a matter of debate. In the present study, we investigated the relationship between social skills and event-related potentials (ERPs) in an auditory selective attention task, in addition to the neurocognitive indices obtained from the degraded-stimulus continuous performance test (CPT) and clinical indices, such as Brief Psychiatric Rating Scale (BRPS) and global assessment of function (GAF) scores. Social skills were assessed using a Japanese version of the structured role play test. Fourteen persons with schizophrenia participated in the study. Non-verbal skills showed a positive correlation with GAF, the performance level, N1 and N2b amplitude in the ERP task, and hit rate in the CPT, and a negative correlation with reaction time in the CPT. Verbal communication skills showed a positive correlation with GAF, the performance level and N2b amplitude in the ERP task, and hit rate in the CPT, and a negative correlation with reaction time in the CPT. Processing skills showed a positive correlation with the performance level and N1 amplitude in the ERP task and a negative correlation with reaction time in the CPT. These findings suggested that the social skill deficits of persons with schizophrenia were related to the vigilance level and controlled stimulus detection processing.  相似文献   
4.
Ikebuchi M  Okanoya K 《Neuroreport》2000,11(17):3915-3919
Males of territorial songbird species have to remember a large number of conspecific songs to defend their territories, while non-territorial songbirds do not need to. A study of a territorial species suggested seemingly unlimited auditory memory size. We measured auditory memory in Bengalese finches, a non-territorial songbird species, to examine whether the auditory memory size for conspecific songs depends on the ecological requirements for song use. Five birds were trained by operant techniques to classify song stimuli into two arbitrary categories. The learning curve reached an asymptote within approximately 100 sessions in all five birds and only eight songs were concurrently remembered on average. Results suggest that ecological requirements for song use are correlated with the auditory song memory capacity.  相似文献   
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6.
AIM: The pathologic feature of aortic aneurysm is considered to be the remodeling of the aortic wall, involving fragmentation and decrease of elastic fibers in the tunica media. Matrix metalloproteinases (MMPs), particularly MMP-2 and MMP-9, have been implicated in collagen and elastin degeneration within the aortic wall. The precise relationship among MMPs and tissue inhibitor of metalloproteinases (TIMPs) is still unclear. We have studied the expression of MMP-2, MMP-9 tissue inhibitor of metalloprotein-1 (TIMP-1), TIMP-2 and membrane type 1-MMP (MT-1-MMP) in the wall of small AAAs (30-45 mm), large AAAs (>45 mm) and controls (<25 mm). We investigated the relationship among expressions of MMP-2, TIMP-2 and MT1-MMP in the walls. METHODS: The aortic walls in the patients with AAA were harvested from the maximum diameter, while the aortic walls in autopsy cases were harvested as controls. We analyzed tissue distribution of cell types by immunochemistry, protein expression by Western blotting and mRNA expression by competitive polymerase chain reaction. RESULTS: They consisted of 11 in controls, 8 in small AAAs and 26 in large AAAs. Among the MMPs-positive-cells, mainly macrophage, MMP-2-positive cells were in the intima, but MMP-9-positive cells in the intima and adventitia. In the small size, MMP-2 and MMP-9 mRNA were higher than those of control. In the large size, MT1-MMP and MMP-9 mRNA were higher than those of the controls. In the mRNA level of the whole AAA, significant correlations were present between MMP-2 and MMP-9, between MMP-2 and TIMP-1, and between MMP-9 and TIMP-1. These expressions were confirmed by Western blotting. CONCLUSION: We concluded as follows: 1) MMP-2 and MMP-9 may play an important role in the developmental process of AAA. 2) TIMP-1 plays an important role of interacting MMP-2 and/or MMP-9. 3) MMP-2 and MT1-MMP may play an important role in the early stages of AAAs.  相似文献   
7.
OBJECTIVE: In an attempt to maintain and expand human stem cells, many investigators have used xenogeneic, especially murine, stromal cells and fetal calf serum. Because of the possible transmission of infectious diseases, however, the safety of the delivery of grafts expanded in culture using xenogeneic cells and serum has been debated. Using primary human marrow stromal cells, we established a novel serum-free culture system to expand human primitive progenitors and transplantable stem cells. MATERIALS AND METHODS: Cord blood CD34(+) cells were cultured on a monolayer of human primary marrow stromal cells in the presence of thrombopoietin (TPO), flt3/flk2 ligand (FL), and/or stem cell factor (SCF) under serum-free conditions. After 2 or 4 weeks of culture, cells were examined for clonogenic progenitors and severe combined immunodeficient disorder (SCID) mouse-reconstituting cells (SRC). RESULTS: In the presence of TPO, FL, and SCF, marrow stromal cells supported more than a 100- and 1,000-fold expansion of CD34(+) cells and colony-forming units in culture after 2 and 4 weeks of incubation, respectively. In addition, cobblestone area-forming cells were expanded more than 18- and 60-fold after 2 and 4 weeks of culture, respectively. Furthermore, SRC assay demonstrated augmented engraftment by cultured cells. CONCLUSION: This ex vivo expansion system should prove valuable in clinical settings in which stromal cells are available from recipients or stem cell donors.  相似文献   
8.
9.
Programmed death‐ligand 1 (PD‐L1) blockade is accepted as a novel strategy for the reactivation of exhausted T cells that express programmed death‐1 (PD‐1). However, the mechanism of PD‐L1‐mediated inhibitory signalling after PD‐L1 cross‐linking by anti‐PD‐L1 monoclonal antibody (mAb) or PD‐1–immunogloblin fusion protein (PD‐1‐Ig) is still unknown, although it may induce cell death of PD‐L1+ cells required for regular immune reactions. In this study, PD‐1‐Ig or anti‐PD‐L1 mAb treatment was tested in cell lines that expressed PD‐L1 and bovine lymphocytes to investigate whether the treatment induces immune reactivation or PD‐L1‐mediated cell death. PD‐L1 cross‐linking by PD‐1‐Ig or anti‐PD‐L1 mAb primarily increased the number of dead cells in PD‐L1high cells, but not in PD‐L1low cells; these cells were prepared from Cos‐7 cells in which bovine PD‐L1 expression was induced by transfection. The PD‐L1‐mediated cell death also occurred in Cos‐7 and HeLa cells transfected with vectors only encoding the extracellular region of PD‐L1. In bovine lymphocytes, the anti‐PD‐L1 mAb treatment up‐regulated interferon‐γ (IFN‐γ) production, whereas PD‐1‐Ig treatment decreased this cytokine production and cell proliferation. The IFN‐γ production in B‐cell‐depleted peripheral blood mononuclear cells was not reduced by PD‐1‐Ig treatment and the percentages of dead cells in PD‐L1+ B cells were increased by PD‐1‐Ig treatment, indicating that PD‐1‐Ig‐induced immunosuppression in bovine lymphocytes could be caused by PD‐L1‐mediated B‐cell death. This study provides novel information for the understanding of signalling through PD‐L1.  相似文献   
10.
ABSTRACT

Individuals with schizophrenia exhibit cognitive impairments, which are related to impairments in social functions. This study investigated the effects of cognitive remediation on cognitive, social, and daily living impairment. Participants were individuals with schizophrenia between 20 and 60 years old (N?=?44). Participants were randomly assigned to two groups: a cognitive remediation intervention group and a non-intervention control group. The control group was provided with conventional drug therapy and either day care or occupational therapy. The intervention group was provided with the “neuropsychological educational approach to cognitive remediation” developed by Medalia and co-workers. We assessed cognitive functions using the brief assessment of cognition in schizophrenia (BACS), and evaluated social and daily living functions using the global assessment of functioning (GAF) scale. Significant group by time interaction effects indicated that verbal memory, working memory, attention, and executive function showed significantly greater improvement at post-intervention for the intervention group than the control group. Social and daily living function also improved in the intervention group and improvements were maintained one year after intervention. These preliminary findings indicate that the combination of cognitive remediation and psychiatric rehabilitation is effective for facilitating improvements in cognitive function and social and daily living functions in individuals with schizophrenia.  相似文献   
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