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71.
Marleen Smits Ellen Keizer Paul Giesen Ellen Catharina Tveter Deilkås Dag Hofoss Gunnar Tschudi Bondevik 《Scandinavian journal of primary health care》2018,36(1):28-35
Objective: To examine patient safety culture in Dutch out-of-hours primary care using the safety attitudes questionnaire (SAQ) which includes five factors: teamwork climate, safety climate, job satisfaction, perceptions of management and communication openness.Design: Cross-sectional observational study using an anonymous web-survey. Setting Sixteen out-of-hours general practitioner (GP) cooperatives and two call centers in the Netherlands. Subjects Primary healthcare providers in out-of-hours services. Main outcome measures Mean scores on patient safety culture factors; association between patient safety culture and profession, gender, age, and working experience.Results: Overall response rate was 43%. A total of 784 respondents were included; mainly GPs (N?=?470) and triage nurses (N?=?189). The healthcare providers were most positive about teamwork climate and job satisfaction, and less about communication openness and safety climate. The largest variation between clinics was found on safety climate; the lowest on teamwork climate. Triage nurses scored significantly higher than GPs on each of the five patient safety factors. Older healthcare providers scored significantly higher than younger on safety climate and perceptions of management. More working experience was positively related to higher teamwork climate and communication openness. Gender was not associated with any of the patient safety factors.Conclusions: Our study showed that healthcare providers perceive patient safety culture in Dutch GP cooperatives positively, but there are differences related to the respondents’ profession, age and working experience. Recommendations for future studies are to examine reasons for these differences, to examine the effects of interventions to improve safety culture and to make international comparisons of safety culture.
- Key Points
Creating a positive patient safety culture is assumed to be a prerequisite for quality and safety. We found that:
??healthcare providers in Dutch GP cooperatives perceive patient safety culture positively;
??triage nurses scored higher than GPs, and older and more experienced healthcare professionals scored higher than younger and less experienced professionals – on several patient safety culture factors; and
??within the GP cooperatives, safety climate and openness of communication had the largest potential for improvement.
72.
73.
Chi-Chung Li Steve Vermeersch William S Denney William P Kennedy John Palcza Adrianna Gipson Tae H Han Rebecca Blanchard Inge De Lepeleire Marleen Depré M Gail Murphy Kristien Van Dyck Jan N de Hoon 《British journal of clinical pharmacology》2015,79(5):831-837
Aims
Calcitonin gene related peptide (CGRP) receptor antagonists are effective acute migraine treatments. A capsaicin-induced dermal vasodilatation (CIDV) model has been developed to provide target-engagement information in healthy volunteers. In the model, CGRP release is provoked after dermal capsaicin application, by activating transient receptor potential vanilloid-type-1 (TRPV1) receptors at peripheral sensory nerves. Laser Doppler imaging is used to quantify CIDV and subsequent inhibition by CGRP receptor antagonists. We sought to evaluate a CGRP receptor antagonist, MK-3207, in the biomarker model and to assess the predictability of the CIDV response to migraine clinical efficacy.Methods
An integrated population pharmacokinetic/pharmacodynamic (PK/PD) model was developed to describe the exposure−response relationship for CIDV inhibition by CGRP and TRPV1 receptor antagonists. MK-3207 dose−response predictions were made based on estimated potency from the PK/PD model and mean plasma concentrations observed at the doses investigated.Results
The results suggested that a 20 mg dose of MK-3207 (EC50 of 1.59 nm) would be required to attain the peripheral CIDV response at a target level that was shown previously to correlate with 2 h clinical efficacy based on phase 3 telcagepant clinical data, and that a plateau of the dose−response would be reached around 40–100 mg. These predictions provided a quantitative rationale for dose selection in a phase 2 clinical trial of MK-3207 and helped with interpretation of the efficacy results from the trial.Conclusions
The integrated CIDV PK/PD model provides a useful platform for characterization of PK/PD relationships and predictions of dose−response relationships to aid in future development of CGRP and TRPV1 receptor antagonists. 相似文献74.
75.
Epithelial proliferation,cell death,and gene expression in experimental colitis: alterations in carbonic anhydrase I,mucin MUC2, and trefoil factor 3 expression 总被引:12,自引:0,他引:12
Renes IB Verburg M Van Nispen DJ Taminiau JA Büller HA Dekker J Einerhand AW 《International journal of colorectal disease》2002,17(5):317-326
BACKGROUND AND AIMS: To gain insight in intestinal epithelial proliferation, cell death, and gene expression during experimental colitis rats were treated with dextran sulfate sodium (DSS) for 7 days. MATERIALS AND METHODS: Proximal and distal colonic segments were excised on days 2, 5, 7, and 28. Epithelial proliferation, cell death, enterocyte gene expression (carbonic anhydrase I (CA I) and goblet cell gene expression (mucin, MUC2; trefoil factor 3, TFF3) were studied immunohistochemically and biochemically. RESULTS: Proliferative activity was decreased in the proximal and distal colon at the onset of disease (day 2). However, during active disease (days 5-7) epithelial proliferation was increased in the entire proximal colon and in the proximity of ulcerations in the distal colon. During DSS treatment the number of apoptotic cells in the epithelium of both colonic segments was increased. In the entire colon surface enterocytes became flattened and CA I negative during active disease (day 5-7). Additionally, CA I levels in the distal colon significantly decreased during this phase. In contrast, during the regenerative phase (day 28) CA I levels were restored in the distal colon and up-regulated in the proximal colon. During all disease phases increased numbers of goblet cells were observed in the surface epithelium of the entire colon. In the distal colon TFF3 expression extended to the bottom of the crypts during active disease. Finally, MUC2 and TFF3 expression was increased in the proximal colon during disease. CONCLUSION: DSS affected the epithelium by inhibiting proliferation and inducing apoptosis. DSS-induced inhibition of CA I expression indicates down-regulation of specific enterocyte functions. Accumulation of goblet cells in the surface epithelium and up-regulation of MUC2 and TFF3 expression in the proximal colon underline the importance of goblet cells in epithelial protection and repair, respectively. 相似文献
76.
Synergistic interaction of the histone deacetylase inhibitor SAHA with the proteasome inhibitor bortezomib in mantle cell lymphoma 总被引:1,自引:0,他引:1
Heider U von Metzler I Kaiser M Rosche M Sterz J Rötzer S Rademacher J Jakob C Fleissner C Kuckelkorn U Kloetzel PM Sezer O 《European journal of haematology》2008,80(2):133-142
Objectives: Mantle cell lymphoma (MCL) is an incurable B cell lymphoma, and novel treatment strategies are urgently needed. We evaluated the effects of combined treatment with the proteasome inhibitor bortezomib and the histone deacetylase inhibitor (HDACi) suberoylanilide hydroxamic acid (SAHA) on MCL. Bortezomib acts by targeting the proteasome, and – among other mechanisms – results in a reduced nuclear factor-kappa B (NF-κB) activity. HDACi promote histone acetylation, and also interfere with NF-κB signaling.
Methods: Human MCL cell lines (JeKo-1, Granta-519 and Hbl-2) were exposed to bortezomib and/or SAHA. Cell viability and apoptosis were quantified by the MTT and annexin-V assay, respectively. Reactive oxygen species (ROS) were analyzed using the fluorophore H2 DCFDA. In addition, activated caspases, proteasome- and NF-κB activity were quantified.
Results: Combined incubation with bortezomib and SAHA resulted in synergistic cytotoxic effects, as indicated by combination index values <1 using the median effect method of Chou and Talalay. The combination of both inhibitors led to a strong increase in apoptosis as compared to single agents and was accompanied by enhanced ROS generation, while each agent alone only modestly induced ROS. The free radical scavenger N -acetyl- l -cysteine blocked the ROS generation and reduced the apoptosis significantly. In addition, coexposure of bortezomib and SAHA led to increased caspase-3, -8 and -9 activity, marked reduction of proteasome activity and decrease of NF-κB activity.
Conclusions: This is the first report giving evidence that SAHA and bortezomib synergistically induce apoptosis in MCL cells. These data build the framework for clinical trials using combined proteasome and histone deacetylase inhibition in the treatment of MCL. 相似文献
Methods: Human MCL cell lines (JeKo-1, Granta-519 and Hbl-2) were exposed to bortezomib and/or SAHA. Cell viability and apoptosis were quantified by the MTT and annexin-V assay, respectively. Reactive oxygen species (ROS) were analyzed using the fluorophore H
Results: Combined incubation with bortezomib and SAHA resulted in synergistic cytotoxic effects, as indicated by combination index values <1 using the median effect method of Chou and Talalay. The combination of both inhibitors led to a strong increase in apoptosis as compared to single agents and was accompanied by enhanced ROS generation, while each agent alone only modestly induced ROS. The free radical scavenger N -acetyl- l -cysteine blocked the ROS generation and reduced the apoptosis significantly. In addition, coexposure of bortezomib and SAHA led to increased caspase-3, -8 and -9 activity, marked reduction of proteasome activity and decrease of NF-κB activity.
Conclusions: This is the first report giving evidence that SAHA and bortezomib synergistically induce apoptosis in MCL cells. These data build the framework for clinical trials using combined proteasome and histone deacetylase inhibition in the treatment of MCL. 相似文献
77.
Visceral leishmaniasis: current status of control,diagnosis, and treatment,and a proposed research and development agenda 总被引:13,自引:0,他引:13
Guerin PJ Olliaro P Sundar S Boelaert M Croft SL Desjeux P Wasunna MK Bryceson AD 《The Lancet infectious diseases》2002,2(8):494-501
Visceral leishmaniasis is common in less developed countries, with an estimated 500000 new cases each year. Because of the diversity of epidemiological situations, no single diagnosis, treatment, or control will be suitable for all. Control measures through case finding, treatment, and vector control are seldom used, even where they could be useful. There is a place for a vaccine, and new imaginative approaches are needed. HIV co-infection is changing the epidemiology and presents problems for diagnosis and case management. Field diagnosis is difficult; simpler, less invasive tests are needed. Current treatments require long courses and parenteral administration, and most are expensive. Resistance is making the mainstay of treatment, agents based on pentavalent antimony, useless in northeastern India, where disease incidence is highest. Second-line drugs (pentamidine and amphotericin B) are limited by toxicity and availability, and newer formulations of amphotericin B are not affordable. The first effective oral drug, miltefosine, has been licensed in India, but the development of other drugs in clinical phases (paromomycin and sitamaquine) is slow. No novel compound is in the pipeline. Drug combinations must be developed to prevent drug resistance. Despite these urgent needs, research and development has been neglected, because a disease that mainly affects the poor ranks as a low priority in the private sector, and the public sector currently struggles to undertake the development of drugs and diagnostics in the absence of adequate funds and infrastructure. This article reviews the current situation and perspectives for diagnosis, treatment, and control of visceral leishmaniasis, and lists some priorities for research and development. 相似文献
78.
Intracellular Ca2+ and delay of ischemia-induced electrical uncoupling in preconditioned rabbit ventricular myocardium 总被引:4,自引:0,他引:4
OBJECTIVE: Short periods of ischemia and reperfusion alter myocardial Ca2+ handling and temporarily induce a mild increase of [Ca2+]i. We hypothesized that these alterations are involved in the cardioprotective mechanism of ischemic preconditioning, possibly via a Ca(2+)-dependent activation of protein kinase C (PKC). METHODS AND RESULTS: In arterially perfused rabbit papillary muscles, we determined Ca2+ transients (indo 1) and indicators of the onset of irreversible ischemic damage, including [Ca2+]i rise, electrical uncoupling and contracture. We tested three protocols of ischemic preconditioning (1-3). In addition, the effects of infusion of staurosporine, a blocker of PKC (4), or glibenclamide, a blocker of K+ATP channels (5) were analyzed. Furthermore, pretreatment with phorbol 12-myrisate 13-acetate (PMA), an activator of PKC (6), or cyclopiazonic acid (CPA), an inhibitor of the SR Ca2+ pump (7) was tested. During periods of reperfusion in the preconditioning protocols, the duration of the Ca2+ transient and the diastolic Ca2+ level temporarily increased. Only if sustained ischemia was induced during these changes of the transients, cardioprotection was present. Similar alterations of the Ca2+ transient concurring with cardioprotection were induced by pretreatment with PMA as well as CPA. Staurosporine and glibenclamide antagonized the reperfusion-induced changes of the Ca2+ transients as well as cardioprotection. If reperfusion was extended until the Ca2+ transient had normalized, cardioprotection was also absent. Under all conditions tested, the diastolic Ca2+ elevation or the Ca2+ transient prolongation prior to sustained ischemia correlated with the postponement of ischemic injury. CONCLUSIONS: A pre-ischemic mild increase of [Ca2-]i presents a common effector of preconditioning. Our data suggest that activation of PKC or opening of K+ATP channels may initiate the pathway leading to an alteration of Ca2+ metabolism and a protected status of the myocardium. 相似文献
79.
As part of a study on etiology of sexually transmitted infections (STI) among 520 women presenting at the STI clinic in Nairobi,
data on partner violence and its correlates were analyzed. Prevalence of lifetime physical violence was 26%, mainly by an
intimate partner (74%). HIV seropositive women had an almost twofold increase in lifetime partner violence. Women with more
risky sexual behavior such as early sexual debut, number of sex partners, history of condom use and of STI, experienced more
partner violence. Parity and miscarriage were associated with a history of lifetime violence. We found an inverse association
between schooling and level of violence. Six percent of the women had been raped. Gender-based violence screening and services
should be integrated into voluntary counseling and testing programs as well as in reproductive health programs. Multi-sector
approaches are needed to change prevailing attitudes towards violence against women.
An erratum to this article can be found at 相似文献
80.
Ellen De Backer Rita Verhelst Hans Verstraelen Geert Claeys Gerda Verschraegen Marleen Temmerman Mario Vaneechoutte 《BMC infectious diseases》2006,6(1):51