The objective of the pharmaceutical industry is to develop new drugs that are safe for human use. In many cases, the accepted approach codified in guidance from regulatory authorities to assess the ...nonclinical safety profile of potential pharmaceuticals is to perform toxicity testing in two species. However, the use of a second species to establish the safety of new pharmaceuticals has been the subject of much scrutiny in recent years and the industry has been repeatedly challenged to reduce, refine, or replace some or all of the animals used to establish the safety of these pharmaceutical candidates. Specifically, the value of the dog in this testing paradigm has been questioned. Publications reviewing available data for marketed drugs suggest that for many drugs, the dog does not identify unique toxicities critical to human safety. The weakness of this approach, however, is that many of the cases where the dog (or any other species) has the greatest impact on drug development are cases for which development decisions based on safety concerns are not shared publicly. The European Federation of Pharmaceutical Industries and Associations (EFPIA) Preclinical Development Expert Group (PDEG) decided to share case studies collected from its membership and the literature to illustrate the value of the dog in drug development decision-making and clinical monitoring practices to protect the safety of trial subjects.
For nonclinical safety-assessment of insulin analogues in vivo, mitogenic effects are compared to that of human insulin. Besides histopathologic evaluation, this usually includes assessment of cell ...proliferation (CP) in mammary glands. Insulin analogue X10 is recommended as positive control, due to its known carcinogenic effect in rat mammary glands. Here, we discuss the mitogenic effect of insulin in vivo and use of X10 as positive control. We present results from 4 nonclinical rat studies evaluating effects of repeated dosing with insulin detemir (≤26 weeks) or degludec (52 weeks) in mammary glands. Studies included human insulin-dosed groups as comparators, CP, and histopathologic evaluation. One study included an X10-dosed group (26 weeks), another ≤3 weeks of dosing with X10 or human insulin evaluating effects of these comparators. Neither human insulin, insulin detemir, degludec, nor X10 induced mammary tumors or increased CP in the studies. The CP marker proliferating cell nuclear antigen varied within/between studies and was not correlated with the remaining markers or CP fluctuations during estrous cycle, whereas the other CP markers, Ki-67 and 5-bromo-2′-deoxyuridine (BrdU), correlated with estrous cycle changes and each other. In conclusion, we propose that the mitogenic effect of insulin in rat mammary glands is weak in vivo. Cell proliferation evaluation in nonclinical safety assessment studies is not predictive of the carcinogenic potential of insulin, thus, the value of including this end point is debatable. Moreover, X10 is not recommended as positive control, due to lack of proliferative effects. Typical CP markers vary greatly in quality, BrdU seemingly most reliable.
Some developmental dual-acting PPARα/γ agonists, such as ragaglitazar, have shown carcinogenic effects in the rodent urinary bladder urothelium after months-years of dosing. We examined early ...(precancerous) changes in the bladder urothelium of rats orally dosed with ragaglitazar, using a newly developed flow cytometric method. Following 3 weeks of oral ragaglitazar dosing, increases in physical size occurred in a generalized fashion in rat bladder urothelial cells, determined by flow cytometry. Protein/DNA measurements confirmed increased protein content of urothelial cells in the bladder, and hypertrophy was observed in the kidney pelvis urothelium by histopathology. In animals exhibiting urothelial hypertrophy, no cell cycle changes were detected in parallel samples of bladder urothelium. Interestingly, urothelial cells from normal rats were found to constitute a unique type of noncycling population, with high G2/M fractions. In summary, our findings showed that in the urothelium of ragaglitazar-treated animals, hypertrophy (increased size and protein content per cell) was an early change, that affected the whole bladder urothelial cell population. The urothelial hypertrophy was primary, i.e., occurred in the absence of similarly pronounced changes in cell cycle distributions. To our knowledge, this is the first report of a direct hypertrophic effect of a PPAR agonist. Urothelial hypertrophy might be a relevant early biological endpoint in mechanistic studies regarding the bladder-carcinogenic effect of PPAR agonists.
Background
Chronic kidney disease (CKD) exacerbates the risk of death due to cardiovascular disease (CVD). Modifications to blood lipid metabolism which manifest as increases in circulating ...triglycerides and reductions in high‐density lipoprotein (HDL) cholesterol are thought to contribute to increased risk. In CKD patients, higher HDL cholesterol levels were not associated with reduced mortality risk. Recent research has revealed numerous mechanisms by which HDL could favourably influence CVD risk. In this study, we compared plasma levels of sphingosine‐1‐phosphate (S1P), HDL‐associated S1P (HDL‐S1P) and HDL‐mediated protection against oxidative stress between CKD and control patients.
Methods
High‐density lipoprotein was individually isolated from 20 CKD patients and 20 controls. Plasma S1P, apolipoprotein M (apoM) concentrations, HDL‐S1P content and the capacity of HDL to protect cardiomyocytes against doxorubicin‐induced oxidative stress in vitro were measured.
Results
Chronic kidney disease patients showed a typical profile with significant reductions in plasma HDL cholesterol and albumin and an increase in triglycerides and pro‐inflammatory cytokines (TNF‐alpha and IL‐6). Unexpectedly, HDL‐S1P content (P = .001) and HDL cardioprotective capacity (P = .034) were increased significantly in CKD patients. Linear regression analysis of which factors could influence HDL‐S1P content showed an independent, negative and positive association with plasma albumin and apoM levels, respectively.
Discussion
The novel and unexpected observation in this study is that uremic HDL is more effective than control HDL for protecting cardiomyocytes against oxidative stress. It is explained by its higher S1P content which we previously demonstrated to be the determinant of HDL‐mediated cardioprotective capacity. Interestingly, lower concentrations of albumin in CKD are associated with higher HDL‐S1P.
Laser desorption ionization (LDI) time-of-flight (TOF) mass spectroscopy of solid
p-dimethylaminophenylpentazole (
1) gives strong peaks of
m/
z −42 and −70. The −70 peak was identified by
15N ...labeling of
1 to be the pentazolate anion (
cyclo-N
5
−). The pentazolate anion is formed by an electron attachment to
1 forming the corresponding radical anion followed by a decomposition into 4-N(CH
3)
2-C
6H
4
and (
cyclo-N
5
−). The LDI TOF experimental study also revealed that the (
cyclo-N
5
−) is very stable. These conclusions are supported by QM calculations at the B3LYP/6-311+G(2df,p) level.
Prehospital care for traumatic brain injury (TBI) is important to prevent secondary brain injury. We aim to compare prehospital care systems within Europe and investigate the association of system ...characteristics with the stability of patients at hospital arrival.
We studied TBI patients who were transported to CENTER-TBI centers, a pan-European, prospective TBI cohort study, by emergency medical services between 2014 and 2017. The association of demographic factors, injury severity, situational factors, and interventions associated with on-scene time was assessed using linear regression. We used mixed effects models to investigate the case mix adjusted variation between countries in prehospital times and interventions. The case mix adjusted impact of on-scene time and interventions on hypoxia (oxygen saturation <90%) and hypotension (systolic blood pressure <100mmHg) at hospital arrival was analyzed with logistic regression.
Among 3878 patients, the greatest driver of longer on-scene time was intubation (+8.3 min, 95% CI: 5.6-11.1). Secondary referral was associated with shorter on-scene time (-5.0 min 95% CI: −6.2- −3.8). Between countries, there was a large variation in response (range: 12-25 min), on-scene (range: 16-36 min) and travel time (range: 15-32 min) and in prehospital interventions. These variations were not explained by patient factors such as conscious level or severity of injury (expected OR between countries: 1.8 for intubation, 1.8 for IV fluids, 2.0 for helicopter). On-scene time was not associated with the regional EMS policy (p= 0.58). Hypotension and/or hypoxia were seen in 180 (6%) and 97 (3%) patients in the overall cohort and in 13% and 7% of patients with severe TBI (GCS <8). The largest association with secondary insults at hospital arrival was with major extracranial injury: the OR was 3.6 (95% CI: 2.6-5.0) for hypotension and 4.4 (95% CI: 2.9-6.7) for hypoxia.
Hypoxia and hypotension continue to occur in patients who suffer a TBI, and remain relatively common in severe TBI. Substantial variation in prehospital care exists for patients after TBI in Europe, which is only partially explained by patient factors.
Enrolling traumatic brain injury (TBI) patients with an inability to provide informed consent in research is challenging. Alternatives to patient consent are not sufficiently embedded in European and ...national legislation, which allows procedural variation and bias. We aimed to quantify variations in informed consent policy and practice.
Variation was explored in the CENTER-TBI study. Policies were reported by using a questionnaire and national legislation. Data on used informed consent procedures were available for 4498 patients from 57 centres across 17 European countries.
Variation in the use of informed consent procedures was found between and within EU member states. Proxy informed consent (N = 1377;64%) was the most frequently used type of consent in the ICU, followed by patient informed consent (N = 426;20%) and deferred consent (N = 334;16%). Deferred consent was only actively used in 15 centres (26%), although it was considered valid in 47 centres (82%).
Alternatives to patient consent are essential for TBI research. While there seems to be concordance amongst national legislations, there is regional variability in institutional practices with respect to the use of different informed consent procedures. Variation could be caused by several reasons, including inconsistencies in clear legislation or knowledge of such legislation amongst researchers.
•Variation is reported in consent procedures between and within European countries.•Discordance between reported consent policy and observed practice was common.•Deferred consent was accepted in many countries, but not frequently used.•Harmonization of consent procedures is needed to improve research efficiency.•Researchers should verify and document a patients ability to provide informed consent.
We aimed to study variation regarding specific end-of-life (EoL) practices in the intensive care unit (ICU) in traumatic brain injury (TBI) patients.
Respondents from 67 hospitals participating in ...The Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study completed several questionnaires on management of TBI patients.
In 60% of the centers, ≤50% of all patients with severe neurological damage dying in the ICU, die after withdrawal of life-sustaining measures (LSM). The decision to withhold/withdraw LSM was made following multidisciplinary consensus in every center. Legal representatives/relatives played a role in the decision-making process in 81% of the centers. In 82% of the centers, age played a role in the decision to withhold/withdraw LSM. Furthermore, palliative therapy was initiated in 79% of the centers after the decision to withdraw LSM was made. Last, withholding/withdrawing LSM was, generally, more often considered after more time had passed, in a patient with TBI, who remained in a very poor prognostic condition.
We found variation regarding EoL practices in TBI patients. These results provide insight into variability regarding important issues pertaining to EoL practices in TBI, which can be useful to stimulate discussions on EoL practices, comparative effectiveness research, and, ultimately, development of recommendations.
•The decision to withhold/withdraw LSM on the ICU was made following multidisciplinary consensus in every center.•Legal representatives and relatives played a role in the decision-making process in 81% of the European neuro trauma centers.•In 82% of the European neuro trauma centers, age played a role in the decision to withhold/withdraw LSM.•Palliative therapy was initiated in 79% of the European neuro trauma centers after the decision to withdraw LSM was made.•Withholding/withdrawing LSM was, generally, more often considered after more time had passed, in a patient with TBI, who remained in a very poor prognostic condition.
Neurocognitive problems associated with posttraumatic stress disorder (PTSD) can interact with impairment resulting from traumatic brain injury (TBI).
We aimed to identify neurocognitive problems ...associated with probable PTSD following TBI in a civilian sample.
The study is part of the CENTER-TBI project (Collaborative European Neurotrauma Effectiveness Research) that aims to better characterize TBI. For this cross-sectional study, we included patients of all severities aged over 15, and a Glasgow Outcome Score Extended (GOSE) above 3. Participants were assessed at six months post-injury on the PTSD Checklist-5 (PCL-5), the Trail Making Test (TMT), the Rey Auditory Verbal Learning Test (RAVLT) and the Cambridge Neuropsychological Test Automated Battery (CANTAB). Primary analysis was a complete case analysis. Regression analyses were performed to investigate the association between the PCL-5 and cognition.
Of the 1134 participants included in the complete case analysis, 13.5% screened positive for PTSD. Probable PTSD was significantly associated with higher TMT-(B-A) (OR = 1.35, 95% CI: 1.14–1.60, p < .001) and lower RAVLT-delayed recall scores (OR = 0.74, 95% CI: 0.61–0.91, p = .004) after controlling for age, sex, psychiatric history, baseline Glasgow Coma Scale and education.
Poorer performance on cognitive tests assessing task switching and, to a lesser extent, delayed verbal recall is associated with probable PTSD in civilians who have suffered TBI.
•Six months after traumatic brain injury 13.5% of people screen positive for PTSD.•Task switching performance and verbal memory are related to probable PTSD.•PTSD severity is related to processing speed and task switching performance.
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