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Kayla Ann Andrews Joel S. Owen James McCarthy David Wesche Nathalie Gobeau Thaddeus H. Grasela Jrg J. Mhrle 《CTS Clinical and Translational Science》2021,14(2):712
Volunteer infection studies using the induced blood stage malaria (IBSM) model have been shown to facilitate antimalarial drug development. Such studies have traditionally been undertaken in single‐dose cohorts, as many as necessary to obtain the dose‐response relationship. To enhance ethical and logistic aspects of such studies, and to reduce the number of cohorts needed to establish the dose‐response relationship, we undertook a retrospective in silico analysis of previously accrued data to improve study design. A pharmacokinetic (PK)/pharmacodynamic (PD) model was developed from initial fictive‐cohort data for OZ439 (mixing the data of the three single‐dose cohorts as: n = 2 on 100 mg, 2 on 200 mg, and 4 on 500 mg). A three‐compartment model described OZ439 PKs. Net growth of parasites was modeled using a Gompertz function and drug‐induced parasite death using a Hill function. Parameter estimates for the PK and PD models were comparable for the multidose single‐cohort vs. the pooled analysis of all cohorts. Simulations based on the multidose single‐cohort design described the complete data from the original IBSM study. The novel design allows for the ascertainment of the PK/PD relationship early in the study, providing a basis for rational dose selection for subsequent cohorts and studies. Study Highlights
- WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
- WHAT QUESTION DID THIS STUDY ADDRESS?
- WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
- HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
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Ableist attitudes and structures are increasingly recognized across all sectors of health care delivery. After Dobbs, novel questions arose in the United States concerning how to protect reproductive autonomy while avoiding discrimination against and devaluation of disabled persons. In this essay, we examine the Louisiana Department of Health's emergency declaration, “List of Conditions That Shall Deem an Unborn Child ‘Medically Futile,’” issued August 1, 2022. We raise a number of medical, ethical, and public health concerns that lead us to argue that the declaration should be rescinded. Analysis of this ethically objectionable declaration provides valuable lessons about how to uphold both reproductive and disability justice in a post-Dobbs landscape. 相似文献
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Joseph Wheatley Zhengyang Liu Joel Loth Mark P. Plummer Jahan C. Penny-Dimri Reny Segal Julian Smith Luke A. Perry 《Acta anaesthesiologica Scandinavica》2023,67(2):131-141
Background
Patients undergoing cardiac surgery are at significant risk of developing postoperative acute kidney injury (AKI). Neutrophil–lymphocyte ratio (NLR) is a widely available inflammatory biomarker which may be of prognostic value in this setting.Methods
We conducted a systematic review and meta-analysis of studies reporting associations between perioperative NLR with postoperative AKI. We searched Medline, Embase and the Cochrane Library, without language restriction, from inception to May 2022 for relevant studies. We meta-analysed the reported odds ratios (ORs) with 95% confidence intervals (CIs) for both elevated preoperative and postoperative NLR with risk of postoperative AKI and need for renal replacement therapy (RRT). We conducted a meta-regression to explore inter-study statistical heterogeneity.Results
Twelve studies involving 10,724 participants undergoing cardiac surgery were included, with eight studies being deemed at high risk of bias using PROBAST modelling. We found statistically significant associations between elevated preoperative NLR and postoperative AKI (OR 1.45, 95% CI 1.18–1.77), as well as postoperative need for RRT (OR 2.37, 95% CI 1.50–3.72). Postoperative NLR measurements were not of prognostic significance.Conclusions
Elevated preoperative NLR is a reliable inflammatory biomarker for predicting AKI following cardiac surgery. 相似文献7.
Clint R. Bellenger John B. Arnold Jonathan D. Buckley Dominic Thewlis Joel T. Fuller 《Journal of Science and Medicine in Sport》2019,22(3):294-299
Objectives
To investigate whether functional overreaching affects locomotor system behaviour when running at fixed relative intensities and if any effects were associated with changes in running performance.Design
Prospective intervention study.Methods
Ten trained male runners completed three training blocks in a fixed order. Training consisted of one week of light training (baseline), two weeks of heavy training designed to induce functional overreaching, and ten days of light taper training designed to allow athletes to recover from, and adapt to, the heavy training. Locomotor behaviour, 5-km time trial performance, and subjective reports of training status (Daily Analysis of Life Demands for Athletes (DALDA) questionnaire) were assessed at the completion of each training block. Locomotor behaviour was assessed using detrended fluctuation analysis of stride intervals during running at speeds corresponding to 65% and 85% of maximum heart rate (HRmax) at baseline.Results
Time trial performance (effect size ±95% confidence interval (ES): 0.16 ± 0.06; p < 0.001), locomotor behaviour at 65% HRmax (ES: ?1.12 ± 0.95; p = 0.026), and DALDA (ES: 2.55 ± 0.80; p < 0.001) were all detrimentally affected by the heavy training. Time trial performance improved relative to baseline after the taper (ES: ?0.16 ± 0.10; p = 0.003) but locomotor behaviour at 65% HRmax (ES: ?1.18 ± 1.17; p = 0.048) and DALDA (ES: 0.92 ± 0.90; p = 0.045) remained impaired.Conclusions
Locomotor behaviour during running at 65% HRmax was impaired by functional overreaching and remained impaired after a 10-day taper, despite improved running performance. Locomotor changes may increase injury risk and should be considered within athlete monitoring programs independently of performance changes. 相似文献8.
Background: Mechanisms underlying associations between early drinking and problems are largely unknown. Objectives: We investigated (a) associations between early age of first intoxication (≤15?years) and past year drinking in different contexts and (b) whether early age of first intoxication is differentially associated with problems in these contexts. Methods: We used survey data collected in 2013–2014 from 405 past-year adolescent drinkers in 24 midsized California cities. Data included demographics; drinking behaviors; age of first intoxication; frequency of being at and drinking at restaurants, bars/nightclubs, outdoor places, and home; and problems. We used multilevel logistic and negative binomial models to account for the clustering of adolescents within cities. Probabilities were corrected to maintain family-wise error rates. Results: Early age of first intoxication was associated with a 120% increase in the odds of drinking at outdoor settings (OR = 2.20, pc < .05). Early age of first intoxication was associated with increased numbers of problems related to drinking in restaurants (IRR = 5.72, pc < .001), outdoor settings (IRR = 3.40, pc < .001), and homes (IRR = 2.84, pc < .001). Later intoxication (≥16?years) was not significantly associated with increased drinking or problems in any of these contexts. Conclusions: Results suggest that underage drinkers who report early intoxication are more likely to drink at outdoor settings, but not other contexts. However, they may differentially experience drinking problems across contexts. To target youths who have experienced intoxication at an early age and to reduce problems, prevention interventions should focus on outdoor settings. 相似文献
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Stephanie A. Castillo Anh K. Pham Dorothea T. Barton Joel A. Lefferts Shaofeng Yan Julia A. Bridge Konstantinos Linos 《Journal of cutaneous pathology》2019,46(3):226-230
Melanoma ex blue nevus (MEBN) is a rare, aggressive, and potentially lethal neoplasm. Distinguishing MEBN from an atypical cellular blue nevus can be very challenging. We report a diagnostically difficult case of MEBN with lymph node metastases, in which single nucleotide polymorphism array and fluorescence in situ hybridization were used to arrive at the correct diagnosis. It was also analyzed by the recently‐introduced proprietary 23‐gene expression signature test. To the best of our knowledge, this is the second reported case of MEBN analyzed by the 23‐gene expression signature, which provided a false‐negative result. More studies are needed to assess the sensitivity and specificity of this test in various melanocytic proliferations. 相似文献