66 resultados para acute drug administration
em BORIS: Bern Open Repository and Information System - Berna - Suiça
Resumo:
To explore chemotherapy patients' experiences of drug administration safety and to investigate the relationship between perceptions of risk and harm from error, staff safety practices, and patients' engagement in error prevention strategies.
Resumo:
To determine longitudinal changes in trabecular volumetric BMD (vBMD) at tibia and radius in young depressive patients under antidepressants using pQCT.
Resumo:
Drug-induced interstitial nephritis can be caused by a plethora of drugs and is characterized by a sudden impairment of renal function, mild proteinuria, and sterile pyuria. For investigation of the possible pathomechanism of this disease, drug-specific T cells were analyzed, their function was characterized, and these in vitro findings were correlated to histopathologic changes that were observed in kidney biopsy specimens. Peripheral blood mononuclear cells from three patients showed a proliferative response to only one of the administered drugs, namely flucloxacillin, penicillin G, and disulfiram, respectively. The in vitro analysis of the flucloxacillin-reactive cells showed an oligoclonal immune response with an outgrowth of T cells bearing the T cell receptor Vbeta9 and Vbeta21.3. Moreover, flucloxacillin-specific T cell clones could be generated from peripheral blood, they expressed CD4 and the alphabeta-T cell receptor, and showed a heterogeneous cytokine secretion pattern with no clear commitment to either a Th1- or Th2-type response. The immunohistochemistry of kidney biopsies of these patients revealed cell infiltrations that consisted mostly of T cells (CD4+ and/or CD8+). An augmented presence of IL-5, eosinophils, neutrophils, CD68+ cells, and IL-12 was observed. In agreement with negative cytotoxicity assays, no cytotoxicity-related molecules such as Fas and perforin were detected by immunohistochemistry. The data indicate that drug-specific T cells are activated locally and orchestrate a local inflammation via secretion of various cytokines, the type of which depends on the cytokine pattern secreted and which probably is responsible for the renal damage.
Resumo:
Although both the subjective and physiological effects of abused psychotropic substances have been characterized, less is known about their effects on brain function. We examined the actions of intravenous diacetylmorphine (heroin), the most widely abused opioid, on regional cerebral blood flow (rCBF), as assessed by perfusion-weighted MR imaging (PWI) in a double-blind and placebo-controlled setting.
Resumo:
BACKGROUND: Constipation is a significant side effect of opioid therapy. We have previously demonstrated that naloxone-3-glucuronide (NX3G) antagonizes the motility-lowering-effect of morphine in the rat colon. AIM: To find out whether oral NX3G is able to reduce the morphine-induced delay in colonic transit time (CTT) without being absorbed and influencing the analgesic effect. METHODS: Fifteen male volunteers were included. Pharmacokinetics: after oral administration of 0.16 mg/kg NX3G, blood samples were collected over a 6-h period. Pharmacodynamics: NX3G or placebo was then given at the start time and every 4 h thereafter. Morphine (0.05 mg/kg) or placebo was injected s.c. 2 h after starting and thereafter every 6 h for 24 h. CTT was measured over a 48-h period by scintigraphy. Pressure pain threshold tests were performed. RESULTS: Neither NX3G nor naloxone was detected in the venous blood. The slowest transit time was observed during the morphine phase, which was significantly different from morphine with NX3G and placebo. The pain perception was not significantly influenced by NX3G. CONCLUSIONS: Orally administered NX3G is able to reverse the morphine-induced delay of CTT in humans without being detected in peripheral blood samples. Therefore, NX3G may improve symptoms of constipation in-patients using opioid medication without affecting opioid-analgesic effects.
Resumo:
Whether the two drug-eluting stents approved by the US Food and Drug Administration-a sirolimus-eluting stent and a paclitaxel-eluting stent-are associated with increased risks of death, myocardial infarction, or stent thrombosis compared with bare-metal stents is uncertain. Our aim was to compare the safety and effectiveness of these stents.
Resumo:
Drug-induced respiratory depression is a common side effect of the agents used in anesthesia practice to provide analgesia and sedation. Depression of the ventilatory drive in the spontaneously breathing patient can lead to severe cardiorespiratory events and it is considered a primary cause of morbidity. Reliable predictions of respiratory inhibition in the clinical setting would therefore provide a valuable means to improve the safety of drug delivery. Although multiple studies investigated the regulation of breathing in man both in the presence and absence of ventilatory depressant drugs, a unified description of respiratory pharmacodynamics is not available. This study proposes a mathematical model of human metabolism and cardiorespiratory regulation integrating several isolated physiological and pharmacological aspects of acute drug-induced ventilatory depression into a single theoretical framework. The description of respiratory regulation has a parsimonious yet comprehensive structure with substantial predictive capability. Simulations relative to the synergistic interaction of the hypercarbic and hypoxic respiratory drive and the global effect of drugs on the control of breathing are in good agreement with published experimental data. Besides providing clinically relevant predictions of respiratory depression, the model can also serve as a test bed to investigate issues of drug tolerability and dose finding/control under non-steady-state conditions.
Resumo:
Objective To compare the effectiveness and safety of three types of stents (sirolimus eluting, paclitaxel eluting, and bare metal) in people with and without diabetes mellitus. Design Collaborative network meta-analysis. Data sources Electronic databases (Medline, Embase, the Cochrane Central Register of Controlled Trials), relevant websites, reference lists, conference abstracts, reviews, book chapters, and proceedings of advisory panels for the US Food and Drug Administration. Manufacturers and trialists provided additional data. Review methods Network meta-analysis with a mixed treatment comparison method to combine direct within trial comparisons between stents with indirect evidence from other trials while maintaining randomisation. Overall mortality was the primary safety end point, target lesion revascularisation the effectiveness end point. Results 35 trials in 3852 people with diabetes and 10 947 people without diabetes contributed to the analyses. Inconsistency of the network was substantial for overall mortality in people with diabetes and seemed to be related to the duration of dual antiplatelet therapy (P value for interaction 0.02). Restricting the analysis to trials with a duration of dual antiplatelet therapy of six months or more, inconsistency was reduced considerably and hazard ratios for overall mortality were near one for all comparisons in people with diabetes: sirolimus eluting stents compared with bare metal stents 0.88 (95% credibility interval 0.55 to 1.30), paclitaxel eluting stents compared with bare metal stents 0.91 (0.60 to 1.38), and sirolimus eluting stents compared with paclitaxel eluting stents 0.95 (0.63 to 1.43). In people without diabetes, hazard ratios were unaffected by the restriction. Both drug eluting stents were associated with a decrease in revascularisation rates compared with bare metal stents in people both with and without diabetes. Conclusion In trials that specified a duration of dual antiplatelet therapy of six months or more after stent implantation, drug eluting stents seemed safe and effective in people both with and without diabetes.
Resumo:
The human aurora family of serine-threonine kinases comprises three members, which act in concert with many other proteins to control chromosome assembly and segregation during mitosis. Aurora dysfunction can cause aneuploidy, mitotic arrest, and cell death. Aurora kinases are strongly expressed in a broad range of cancer types. Aurora A expression in tumors is often associated with gene amplification, genetic instability, poor histologic differentiation, and poor prognosis. Aurora B is frequently expressed at high levels in a variety of tumors, often coincidently with aurora A, and expression level has also been associated with increased genetic instability and clinical outcome. Further, aurora kinase gene polymorphisms are associated with increased risk or early onset of cancer. The expression of aurora C in cancer is less well studied. In recent years, several small-molecule aurora kinase inhibitors have been developed that exhibit preclinical activity against a wide range of solid tumors. Preliminary clinical data from phase I trials have largely been consistent with cytostatic effects, with disease stabilization as the best response achieved in solid tumors. Objective responses have been noted in leukemia patients, although this might conceivably be due to inhibition of the Abl kinase. Current challenges include the optimization of drug administration, the identification of potential biomarkers of tumor sensitivity, and combination studies with cytotoxic drugs. Here, we summarize the most recent preclinical and clinical data and discuss new directions in the development of aurora kinase inhibitors as antineoplastic agents.
Resumo:
BACKGROUND: T cells play a key role in delayed-type drug hypersensitivity reactions. Their reactivity can be assessed by their proliferation in response to the drug in the lymphocyte transformation test (LTT). However, the LTT imposes limitations in terms of practicability, and an alternative method that is easier to implement than the LTT would be desirable. METHODS: Four months to 12 years after acute drug hypersensitivity reactions, CD69 upregulation on T cells of 15 patients and five healthy controls was analyzed by flow cytometry. RESULTS: All 15 LTT-positive patients showed a significant increase of CD69 expression on T cells after 48 h of drug-stimulation exclusively with the drugs incriminated in drug-hypersensitivities. A stimulation index of 2 as cut-off value allowed discrimination between nonreactive and reactive T cells in LTT and CD69 upregulation. T cells (0.5-3%) showed CD69 up-regulation. The reactive cell population consisted of a minority of truly drug reactive T cells secreting cytokines and a higher number of bystander T cells activated by IL-2 and possibly other cytokines. CONCLUSIONS: CD69 upregulation was observed after 2 days in all patients with a positive LTT after 6 days, thus appearing to be a promising tool to identify drug-reactive T cells in the peripheral blood of patients with drug-hypersensitivity reactions.
Resumo:
BACKGROUND The sympathetic nervous system (SNS) is an important regulator of cardiovascular function. Activation of SNS plays an important role in the pathophysiology and the prognosis of cardiovascular diseases such as heart failure, acute coronary syndromes, arrhythmia, and possibly hypertension. Vasodilators such as adenosine and sodium nitroprusside are known to activate SNS via baroreflex mechanisms. Because vasodilators are widely used in the treatment of patients with cardiovascular diseases, the aim of the present study was to assess the influence of clinically used dosages of isosorbide dinitrate and captopril on sympathetic nerve activity at rest and during stimulatory maneuvers. METHODS AND RESULTS Twenty-eight healthy volunteers were included in this double-blind placebo-controlled study, and muscle sympathetic nerve activity (MSA; with microelectrodes in the peroneal nerve), blood pressure, heart rate, and neurohumoral parameters were measured before and 90 minutes after the oral administration of 40 mg isosorbide dinitrate or 6.25 mg captopril. Furthermore, a 3-minute mental stress test and a cold pressor test were performed before and 90 minutes after drug administration. Resting MSA did not change after captopril and decreased compared with placebo (P < .05 versus placebo), whereas isosorbide dinitrate led to a marked increase in MSA (P < .05). Systolic blood pressure was reduced by isosorbide dinitrate (P < .05), whereas captopril decreased diastolic blood pressure (P < .05). The increases in MSA, blood pressure, and heart rate during mental stress were comparable before and after drug administration regardless of the medication. During cold pressor test, MSA and systolic and diastolic blood pressures increased to the same degree independent of treatment, but after isosorbide dinitrate, the increase in MSA seemed to be less pronounced. Heart rate did not change during cold stimulation. Plasma renin activity increased after captopril and isosorbide dinitrate (P < .05), whereas placebo had no effect. Endothelin-1 increased after placebo and isosorbide dinitrate (P < .05) but not after captopril. CONCLUSIONS Thus, captopril suppressed MSA despite lowering of diastolic blood pressure but allowed normal adaptation of the SNS during mental or physical stress. In contrast, the nitrate strongly activated the SNS under baseline conditions. These findings demonstrate that vasodilators differentially interact with the SNS, which could be of importance in therapeutic strategies for the treatment of patients with cardiovascular diseases.
Resumo:
OBJECTIVES The aim of the current Valve Academic Research Consortium (VARC)-2 initiative was to revisit the selection and definitions of transcatheter aortic valve implantation (TAVI) clinical endpoints to make them more suitable to the present and future needs of clinical trials. In addition, this document is intended to expand the understanding of patient risk stratification and case selection. BACKGROUND A recent study confirmed that VARC definitions have already been incorporated into clinical and research practice and represent a new standard for consistency in reporting clinical outcomes of patients with symptomatic severe aortic stenosis (AS) undergoing TAVI. However, as the clinical experience with this technology has matured and expanded, certain definitions have become unsuitable or ambiguous. METHODS AND RESULTS Two in-person meetings (held in September 2011 in Washington, DC, and in February 2012 in Rotterdam, The Netherlands) involving VARC study group members, independent experts (including surgeons, interventional and noninterventional cardiologists, imaging specialists, neurologists, geriatric specialists, and clinical trialists), the US Food and Drug Administration (FDA), and industry representatives, provided much of the substantive discussion from which this VARC-2 consensus manuscript was derived. This document provides an overview of risk assessment and patient stratification that need to be considered for accurate patient inclusion in studies. Working groups were assigned to define the following clinical endpoints: mortality, stroke, myocardial infarction, bleeding complications, acute kidney injury, vascular complications, conduction disturbances and arrhythmias, and a miscellaneous category including relevant complications not previously categorized. Furthermore, comprehensive echocardiographic recommendations are provided for the evaluation of prosthetic valve (dys)function. Definitions for the quality of life assessments are also reported. These endpoints formed the basis for several recommended composite endpoints. CONCLUSIONS This VARC-2 document has provided further standardization of endpoint definitions for studies evaluating the use of TAVI, which will lead to improved comparability and interpretability of the study results, supplying an increasingly growing body of evidence with respect to TAVI and/or surgical aortic valve replacement. This initiative and document can furthermore be used as a model during current endeavors of applying definitions to other transcatheter valve therapies (for example, mitral valve repair).
Resumo:
Objectives: To update the 2006 systematic review of the comparative benefits and harms of erythropoiesis-stimulating agent (ESA) strategies and non-ESA strategies to manage anemia in patients undergoing chemotherapy and/or radiation for malignancy (excluding myelodysplastic syndrome and acute leukemia), including the impact of alternative thresholds for initiating treatment and optimal duration of therapy. Data sources: Literature searches were updated in electronic databases (n=3), conference proceedings (n=3), and Food and Drug Administration transcripts. Multiple sources (n=13) were searched for potential gray literature. A primary source for current survival evidence was a recently published individual patient data meta-analysis. In that meta-analysis, patient data were obtained from investigators for studies enrolling more than 50 patients per arm. Because those data constitute the most currently available data for this update, as well as the source for on-study (active treatment) mortality data, we limited inclusion in the current report to studies enrolling more than 50 patients per arm to avoid potential differential endpoint ascertainment in smaller studies. Review methods: Title and abstract screening was performed by one or two (to resolve uncertainty) reviewers; potentially included publications were reviewed in full text. Two or three (to resolve disagreements) reviewers assessed trial quality. Results were independently verified and pooled for outcomes of interest. The balance of benefits and harms was examined in a decision model. Results: We evaluated evidence from 5 trials directly comparing darbepoetin with epoetin, 41 trials comparing epoetin with control, and 8 trials comparing darbepoetin with control; 5 trials evaluated early versus late (delay until Hb ≤9 to 11 g/dL) treatment. Trials varied according to duration, tumor types, cancer therapy, trial quality, iron supplementation, baseline hemoglobin, ESA dosing frequency (and therefore amount per dose), and dose escalation. ESAs decreased the risk of transfusion (pooled relative risk [RR], 0.58; 95% confidence interval [CI], 0.53 to 0.64; I2 = 51%; 38 trials) without evidence of meaningful difference between epoetin and darbepoetin. Thromboembolic event rates were higher in ESA-treated patients (pooled RR, 1.51; 95% CI, 1.30 to 1.74; I2 = 0%; 37 trials) without difference between epoetin and darbepoetin. In 14 trials reporting the Functional Assessment of Cancer Therapy (FACT)-Fatigue subscale, the most common patient-reported outcome, scores decreased by −0.6 in control arms (95% CI, −6.4 to 5.2; I2 = 0%) and increased by 2.1 in ESA arms (95% CI, −3.9 to 8.1; I2 = 0%). There were fewer thromboembolic and on-study mortality adverse events when ESA treatment was delayed until baseline Hb was less than 10 g/dL, in keeping with current treatment practice, but the difference in effect from early treatment was not significant, and the evidence was limited and insufficient for conclusions. No evidence informed optimal duration of therapy. Mortality was increased during the on-study period (pooled hazard ratio [HR], 1.17; 95% CI, 1.04 to 1.31; I2 = 0%; 37 trials). There was one additional death for every 59 treated patients when the control arm on-study mortality was 10 percent and one additional death for every 588 treated patients when the control-arm on-study mortality was 1 percent. A cohort decision model yielded a consistent result—greater loss of life-years when control arm on-study mortality was higher. There was no discernible increase in mortality with ESA use over the longest available followup (pooled HR, 1.04; 95% CI, 0.99 to 1.10; I2 = 38%; 44 trials), but many trials did not include an overall survival endpoint and potential time-dependent confounding was not considered. Conclusions: Results of this update were consistent with the 2006 review. ESAs reduced the need for transfusions and increased the risk of thromboembolism. FACT-Fatigue scores were better with ESA use but the magnitude was less than the minimal clinically important difference. An increase in mortality accompanied the use of ESAs. An important unanswered question is whether dosing practices and overall ESA exposure might influence harms.
Resumo:
While glucocorticoid (GC) administration appears to be beneficial during the acute phase of treatment of neonates at risk of developing chronic lung disease, it is still not clear whether steroid application has an adverse long-term effect on the lung maturation. Thus, the goal of the present work was to analyze GC effects on the pulmonary structure in a rat model where dosage and timing of drug administration were adapted to the therapeutic situation in human neonatology. The animals received daily a maximum of 0.1 mg dexamethasone phosphate per kilogram body weight during the first 4 postnatal days. Investigations were performed at the light microscopic level by means of a digital image analysis system. While there were no differences in the lung architecture between experimental animals and controls on day 4, the earliest time point of observation, we found a widening of airspaces with a concomitant decrease in the alveolar surface area density, representing a loss of parenchymal complexity, on days 10 and 21 in treated rats. On days 36 and 60, however, no alterations in the pulmonary parenchyma could be detected in experimental animals. We conclude from these findings that the GC-induced initial inhibition of development (days 10 and 21) was completely reversed, so that a normal parenchymal architecture and also a normal alveolar surface area density were found in adult rats (days 36 and 60). From the results obtained using the regimen of GC administration described, mimicking more closely the steroid treatment in human neonatology, we conclude that the observed short-term adverse effects on lung development can be fully compensated until adult age.
Resumo:
BACKGROUND Inability to predict the therapeutic effect of a drug in individual pain patients prolongs the process of drug and dose finding until satisfactory pharmacotherapy can be achieved. Many chronic pain conditions are associated with hypersensitivity of the nervous system or impaired endogenous pain modulation. Pharmacotherapy often aims at influencing these disturbed nociceptive processes. Its effect might therefore depend on the extent to which they are altered. Quantitative sensory testing (QST) can evaluate various aspects of pain processing and might therefore be able to predict the analgesic efficacy of a given drug. In the present study three drugs commonly used in the pharmacological management of chronic low back pain are investigated. The primary objective is to examine the ability of QST to predict pain reduction. As a secondary objective, the analgesic effects of these drugs and their effect on QST are evaluated. METHODS/DESIGN In this randomized, double blinded, placebo controlled cross-over study, patients with chronic low back pain are randomly assigned to imipramine, oxycodone or clobazam versus active placebo. QST is assessed at baseline, 1 and 2 h after drug administration. Pain intensity, side effects and patients' global impression of change are assessed in intervals of 30 min up to two hours after drug intake. Baseline QST is used as explanatory variable to predict drug effect. The change in QST over time is analyzed to describe the pharmacodynamic effects of each drug on experimental pain modalities. Genetic polymorphisms are analyzed as co-variables. DISCUSSION Pharmacotherapy is a mainstay in chronic pain treatment. Antidepressants, anticonvulsants and opioids are frequently prescribed in a "trial and error" fashion, without knowledge however, which drug suits best which patient. The present study addresses the important need to translate recent advances in pain research to clinical practice. Assessing the predictive value of central hypersensitivity and endogenous pain modulation could allow for the implementation of a mechanism-based treatment strategy in individual patients. TRIAL REGISTRATION Clinicaltrials.gov, NCT01179828.