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1.

A key goal for implementation science is the identification of evidence-based consultation protocols and the active ingredients within these protocols that drive clinician behavior change. The current study examined clinicians’ self-coding of fidelity as a potential active ingredient of consultation for the Attachment and Biobehavioral Catch-up (ABC) intervention. It also examined two other potential predictors of clinician fidelity in response to consultation: dosage of consultation and working alliance. Twenty-nine clinicians (97% female, 62% White, M age?=?34 years) participated in a year of weekly fidelity-focused ABC consultation sessions, for which clinicians self-coded fidelity and received consultant feedback on both their coding and their fidelity. Data from the ABC fidelity measure were available for 1067 sessions coded by consultants, and clinicians’ self-coding accuracy was calculated from 1044 sessions coded by both clinicians and consultants. Alliance was measured with the Working Alliance Inventory—Trainee and Supervisor Versions. The study was observational, and fidelity and self-coding accuracy were modeled across time using hierarchical linear modeling. Clinicians’ ABC fidelity, as well as their self-coding accuracy, increased over the course of consultation. Clinicians’ self-coding accuracy predicted their initial fidelity and growth in fidelity. Working alliance was also linked to fidelity and self-coding accuracy. These results suggest that clinician self-coding should be further examined as an active ingredient of consultation. The study has important implications for the design of consultation procedures and fidelity assessments.

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CTLA-4 is required for the induction of high dose oral tolerance   总被引:5,自引:3,他引:5  
Mucosal and systemic administrations of high dose antigens induce long- lasting peripheral T cell tolerance. We and others have shown that high dose peripheral T cell tolerance is mediated by anergy or deletion and is preceded by T cell activation. Co-stimulatory molecules B7-1 (CD80)/B7-2 (CD86) and their counter-receptors CD28/CTLA-4 play pivotal roles in T cell activation and immune regulation. In the present study, we examined the roles of the B7 co-stimulation pathway in the generation of high dose peripheral T cell tolerance. We found that blocking B7:CD28/CTLA-4 interaction at the time of tolerance induction partially prevented T cell tolerance, whereas selective blockade of B7:CTLA-4 interaction completely abrogated peripheral T cell tolerance induced by either oral or i.p. antigens. These results suggest that CTLA-4-mediated feedback regulation plays a crucial role in the induction of high dose peripheral T cell tolerance.   相似文献   
4.
Needle biopsy of renal allografts: comparison of two techniques   总被引:2,自引:0,他引:2  
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.  相似文献   
5.
PURPOSE: Prostate specific antigen (PSA) may temporarily increase following radiotherapy for prostate cancer without signaling cancer recurrence. We describe this phenomenon which is called PSA bounce. MATERIALS AND METHODS: From 1984 to 1995, 779 stage T1T2N0 cancer cases were treated with simultaneous radiotherapy with a 125iodine prostate implant followed by external beam radiation. Median pretreatment PSA was 7.7 ng./ml. (range 0.3 to 188). PSA bounce was defined as an increase of 0.1 ng./ml. or greater above the preceding PSA level after simultaneous radiation followed by a subsequent decrease below that level. Disease-free status was defined as the ability to achieve and maintain posttreatment PSA 0.2 ng./ml. or less. RESULTS: PSA bounce was observed in 35% of men (273 of 779). Median time to PSA bounce was 18 months from the time of implant and 92% of bounces were observed within 36 months. Median pre-bounce PSA was 0.7 ng/ml. (range 0.1 to 8.9) and median bounce height (increase above the pre-bounce level) was 0.4 ng./ml. (range 0.1 to 15.8). No distinguishing characteristics were observed between men with PSA bounce and those with cancer recurrence, and bounce had no prognostic significance relative to recurrence. CONCLUSIONS: PSA bounce is common following seed implantation for prostate cancer. It produces anxiety in men previously treated for prostate cancer and confounds the diagnosis of recurrence.  相似文献   
6.
PURPOSE: The aim of this study was to design and evaluate in the laboratory a new intraocular lens (IOL) intended to provide superior ocular optical quality by reducing spherical aberration. METHODS: Corneal topography measurements were performed on 71 cataract patients using an Orbscan I. The measured corneal surface shapes were used to determine the wavefront aberration of each cornea. A model cornea was then designed to reproduce the measured average spherical aberration. This model cornea was used to design IOLs having a fixed amount of negative spherical aberration that partially compensates for the average positive spherical aberration of the cornea. Theoretical and physical eye models were used to assess the expected improvement in optical quality of an eye implanted with this lens. RESULTS: Measurements of optical quality provided evidence that if this modified prolate IOL was centered within 0.4 mm and tilted less than 7 degrees, it would exceed the optical performance of a conventional spherical IOL. This improvement occurred without an apparent loss in depth of focus. CONCLUSION: A new IOL with a prolate anterior surface, designed to partially compensate for the average spherical aberration of the cornea, is intended to improve the ocular optical quality of pseudophakic patients.  相似文献   
7.
Maternal oxidative balance and immune health impact both placental and fetal developments. The alkylating agent methylnitrosourea (MNU) increases placental oxidative stress and alters fetal development; the proposed mechanism is placental inflammation, endothelial dysfunction, and cell loss resulting in reduced fetal-maternal circulation and fetal hypoxia. Results of the present study suggest two primary cellular signaling pathways associated with placental and fetal malformations in mice following mid-gestational MNU: Jak-STAT and NFkappaB. Activation of these pathways was associated with increased placental granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin-2 (IL-2), IL-4, leptin, macrophage chemotactic protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-alpha), thrombopoietin (TPO), and vasculoendothelial growth factor (VEGF), and decreased IL-10. Maternal immunostimulation with Freund's complete adjuvant (FCA) or interferon-gamma (IFN-gamma), or antioxidant supplementation with butylated hydroxytoluene (BHT) partially restored placental cytokine levels relative to controls, suggesting that maternal immunity and oxidative stress may both contribute to placental dysregulation and fetal maldevelopment following MNU.  相似文献   
8.
Aberrant major histocompatibility complex class II (MHC-II) surface expression on antigen presenting cells (APCs) is associated with dysregulated immune homeostasis. Lead (Pb) is known to increase MHC-II surface expression on murine peritoneal macrophages ex vivo at concentrations exceeding 25 μM. Little data exist examining this effect at physiologically relevant concentrations. To address this deficit, we examined the effects of Pb on MHC-II surface expression, secondary T-cell activation markers (CD80, CD86, CD40), cell viability, cellular metabolic activity, and β-hexosaminidase activity in RAW 267.4 macrophage cell lines, with changes in cell ultrastructure evaluated by electron and confocal microscopy. Pb induced an increase in MHC-II, CD86, and lysosome-associated LAMP-1 and LAMP-2 surface mean expression during one doubling cycle (17 h), which was mirrored by increased β-hexosaminidase activity. Although cell viability was unaffected, cellular metabolism was inhibited. Electron microscopy revealed evidence of lipid vacuolization, macroautophagy and myelin figure formation in cells cultured with either Pb or LPS. Confocal microscopy with antibodies against LC3B showed a punctate pattern consistent with the presence of mature autophagosomes. Collectively, these data suggest that 2.5–5.0 μM Pb increased MHC-II surface expression by inhibiting metabolic activity, inducing autophagy, and increasing MHC-II trafficking in a macrophage cell line.  相似文献   
9.
The correlation of coronary artery disease (CAD) with pro-oxidant/antioxidant balance and oxidative DNA damage was investigated.Seventy-seven patients with CAD and 44 healthy individuals as control were included in this study. The comparative ratios of ubiquinol-10/ubiquinone-10, 8-hydroxy-2''-deoxyguanosine/deoxyguanosine and the level of MDA measured by HPLC and the activities of GPX and SOD by colorimetric approach in blood samples obtained from patients with CAD were unraveled.8-OHdG/dG ratios, serum MDA level and GPX activity were found significantly elevated level in serum of CAD patients compared to control group. The SOD activity was observed in stable levels in CAD patients. Ubiquinol-10/ubiquinone-10 ratio was significantly lower in patients with CAD than the controls.The positive correlation was observed between 8-OHdG/dG ratios in both MDA levels and GPX activity, while the significant negative correlation was seemed between the ratio of 8-OHdG/dG and ubiquinol-10/ ubiquinone-10 as well as MDA levels and ubiquinol-10/ ubiquinone-10 ratio.We conclude that, both the disruption of pro-oxidant/antioxidant balance and oxidative stress in DNA may play an important role in the pathogenesis of coronary artery disease.  相似文献   
10.
Simon  SI; Rochon  YP; Lynam  EB; Smith  CW; Anderson  DC; Sklar  LA 《Blood》1993,82(4):1097-1106
We have recently found that antibodies to L-selectin, the homing receptor on neutrophils, are as effective as those to beta 2-integrin at blocking formyl peptide-stimulated aggregation. Therefore, we investigated the requirements for expression of L-selectin and beta 2- integrin on adjacent cells during aggregation. Fluorescence flow cytometry allowed characterization of aggregates on the basis of size and color, as well as antibody binding to these two adhesive molecules. Formyl peptide-stimulated aggregate formation was measured for individual populations fluorescently labeled red (LDS-751) or green (CD44-FITC), and interpopulation red-green cell conjugates. Blocking either the beta 2-integrin or L-selectin adhesive epitope with monoclonal antibody on individual cell populations resulted in an approximately 50% reduction in two-color aggregation as compared with that in unblocked samples. Shedding the L-selectin on a cell population by preincubation with complexes of lipopolysaccharide and its plasma membrane binding protein also decreased aggregation to a control population by approximately 50%. We examined the aggregation of neutrophils from patients genetically deficient in beta 2-integrin and clinically leukocyte adhesion deficient (LAD). LAD adhesion to normal neutrophils was dependent on the expression of L-selectin on LAD cells and beta 2-integrin on normal cells. Thus, the minimum requirement for adhesion between two mixed populations of neutrophils was that one population expressed the beta 2-integrin and the other expressed the L- selectin adhesive epitope.  相似文献   
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