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81.
In vivo expression of the B7 costimulatory molecule by subsets of antigen-presenting cells and the malignant cells of Hodgkin's disease 总被引:10,自引:0,他引:10
Munro JM; Freedman AS; Aster JC; Gribben JG; Lee NC; Rhynhart KK; Banchereau J; Nadler LM 《Blood》1994,83(3):793-798
The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites. 相似文献
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Ventilatory acclimatization (VA) to hypoxia alters cerebrovascular responses to arterial blood gas perturbations. For example, after VA, cerebral blood flow (CBF) is elevated, at a given arterial CO2 tension (PaCO2), compared to CBF before VA. This experiment examined the effects of VA to 72 h of normobaric hypoxia [arterial O2 tension (PaO2) approx. 40 mmHg, O2 saturation in arterial blood approx. 50%] on total and regional cerebrovascular resistance (CVR and rCVR) and cerebral O2 extraction fraction (OEF) in 32 conscious sheep. Four different O2-CO2 gas combinations were sequentially administered to each sheep before and after VA. CVR and rCVR were calculated from CBF (radiolabeled microspheres) and arterial and cerebral downstream pressures; OEF was calculated from arterial and cerebral venous O2 contents. After VA, during hyperoxia, CVR and rCVR tended to be lower during both hypocapnia and hypercapnia. During hypoxia, although CVR and rCVR were slightly less during hypocapnia, CVR and rCVR during hypercapnia were surprisingly increased. The post-VA increases in mean CVR and mean rCVR during hypoxic gas combinations differed from the post-VA decreases during hyperoxic gas combinations (0.04 less than or equal to P less than or equal to 0.11). In contrast, although VA decreased OEF during three of four gas combinations (P less than or equal to 0.003), there was a greater mean post-VA decrease in OEF during hypercapnic gas combinations than during hypocapnic gas combinations (P = 0.025); decreases in OEF were correlated with decreases in cerebral O2 consumption. The post-VA CVR responses may reflect altered neurocirculatory control by the arterial chemoreflex; the OEF responses suggest relative cerebral hyperperfusion.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
83.
Normal synthesis and expression of endothelial IIb/IIIa in Glanzmann's thrombasthenia 总被引:2,自引:0,他引:2
Glanzmann's thrombasthenia is a bleeding disorder, inherited in an autosomal recessive way and characterized by an absence or deficiency of the platelet glycoprotein (GP) IIb/IIIa complex. Recently, we and others demonstrated that cultured human umbilical vein endothelial cells synthesized a membrane protein complex similar to the platelet GP IIb/IIIa complex. In this article, we demonstrate that endothelial cells isolated from the umbilical vein of a newborn with Glanzmann's thrombasthenia, as compared with normal endothelial cells, show no difference in their ability to synthesize and express this GP IIb/IIIa complex. Our results indicate that Glanzmann's thrombasthenia is not accompanied by an "endotheliopathy." 相似文献
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Shelli L. Feder Meredith Campbell Britton Sarwat I. Chaudhry 《Journal of pain and symptom management》2018,55(3):930-937
Context
The number of patients discharged from acute care hospitals to skilled nursing facilities (SNFs) is rising. These patients have increasingly complex needs and many experience poor outcomes while under SNF care, including hospital readmissions. Patients' goals of care (GoC) are viewed as a factor contributing to unplanned hospital readmissions from SNFs. However, clinicians' perspectives of GoC for hospitalized patients discharged to SNFs are not well-described.Objectives
To explore how clinicians view GoC for hospitalized patients discharged to SNFs.Methods
Qualitative study using semi-structured interviews and thematic analysis.Results
Forty-one clinicians from one acute care hospital and two SNFs completed interviews ranging in length from 14 to 52 minutes (mean = 32 minutes). Of the sample, 22% were nurses, 20% physicians, 15% were from care management, and 15% were from social services. Respondents viewed patients' GoC for continuing treatment at the SNF as important, but acknowledged that they were infrequently discussed during hospitalization. Many respondents felt that patients and families had unrealistic GoC for SNF care. Factors that contributed to unrealistic GoC included patients' limited knowledge of disease processes, prognosis, and treatment options; and inconsistent or insufficient communication of GoC among hospital and SNF clinicians, the patient, and family members. Respondents associated a lack of GoC or unrealistic GoC with patients' dissatisfaction with SNF care, unplanned transitions to hospice, and hospital readmissions.Conclusions
Respondents reported that GoC conversations infrequently occurred during hospitalization, contributing to unrealistic patient and family expectations for SNF care and poor patient outcomes. Interventions are needed that facilitate timely, accurate, and consistent GoC discussions across care continuums. 相似文献88.
Kelly L. Fargo Jessica Johnston Kurt B. Stevenson Meredith Deutscher Erica E. Reed 《Hospital pharmacy》2015,50(6):496-504
Background:
Studies evaluating the impact of passive cost visibility tools on antibiotic prescribing are lacking.Objective:
The objective of this study was to evaluate whether the implementation of a passive antibiotic cost visibility tool would impact antibiotic prescribing and decrease antibiotic spending.Methods:
An efficiency and effectiveness initiative (EEI) was implemented in October 2012. To support the EEI, an antibiotic cost visibility tool was created in June 2013 displaying the relative cost of antibiotics. Using an observational study of interrupted time series design, 3 time frames were studied: pre EEI, post EEI, and post cost visibility tool implementation. The primary outcome was antibiotic cost per 1,000 patient days. Secondary outcomes included case mix index (CMI)–adjusted antibiotic cost per 1,000 patient days and utilization of the cost visibility tool.Results:
Initiation of the EEI was associated with a $4,675 decrease in antibiotic cost per 1,000 patient days (P = .003), and costs continued to decrease in the months following EEI (P = .009). After implementation of the cost visibility tool, costs remained stable (P = .844). Despite CMI increasing over time, adjustment for CMI had no impact on the directionality or statistical significance of the results.Conclusion:
Our study demonstrated a significant and sustained decrease in antibiotic cost per 1,000 patient days when focused medication cost reduction efforts were implemented, but passive cost visibility tool implementation was not associated with additional cost reduction. Antibiotic cost visibility tools may be of most benefit when prior medication cost reduction efforts are lacking or when an active intervention is incorporated. 相似文献89.
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