OBJECTIVES:Brain death induces a massive inflammatory response. However, the influence of this inflammatory response on organ procurement, transplantation, and recipient outcome is unknown. We ...describe the inflammatory response characteristics in brain-dead organ donors and examine associations with organ transplantation and recipient survival. We test the hypothesis that increased inflammatory response is associated with fewer organs transplanted and decreased recipient survival.
DESIGN:Prospective, observational, cohort study.
SETTING:Two large intensive care units of tertiary care university hospitals in the United States.
PATIENTS:We recruited 30 consecutive brain-dead organ donors and 78 recipients between April 11, 2004, and November 23, 2004; recipients were followed through May 2005. Following declaration of brain death, we collected data on donor demographics, mechanism of brain death, number of organs procured and transplanted, and recipient characteristics. Plasma cytokines (tumor necrosis factor, interleukin-6, interleukin-10) were measured in donors at baseline following study enrollment, every hour for the first 4 hrs, and immediately before organ procurement for transplantation.
INTERVENTIONS:None.
MEASUREMENTS AND MAIN RESULTS:We examined the relationships among clinical characteristics, demographics, and cytokine response in donors and their influence on organ procurement and transplantation using multivariable regression and recipient’s 6-month hospital-free survival using a Cox proportional hazards regression. One hundred-eighteen organs were procured from 30 donors, and 91 (77%) were transplanted (mean of three organs transplanted per donor). All cytokines were increased following brain death. Older age in donors was significantly associated with lower number of organs transplanted (p < .001). Higher plasma interleukin-6 concentrations in donors before organ procurement was significantly associated with lower 6-month hospital-free survival in recipients (hazard ratio 1.77; 95% confidence interval, 1.17–2.69, p < .007).
CONCLUSIONS:Among brain-dead organ donors, older age donors contribute fewer organs for transplantation, and increased donor interleukin-6 level before organ procurement is associated with lower recipient six-month hospital-free survival.
Hepatic steatosis is associated with significant morbidity and mortality after liver resection and transplantation. Although apoptosis is a key mechanism of reperfusion injury in the normal liver, ...the pathway leading to cell death in steatotic hepatocytes is unknown. A model of hepatic ischemia and reperfusion injury in fatty and lean Zucker rats was used. Fatty animals had increased aspartate aminotransferase (AST) release and decreased survival after 60 minutes of ischemia compared with lean animals. Apoptosis was the predominant form of cell death in the lean rats (82%), whereas necrosis was minimal. In contrast, fatty animals developed only moderate amounts of apoptosis but showed massive necrosis (73%) after 24 hours of reperfusion. Intracellular mediators of apoptosis, such as caspase 8, caspase 3, and cytochrome c, were significantly lower in the steatotic than in the lean liver indicating dysfunction in activation of the apoptotic pathway. The high percentage of necrosis in the steatotic rats was associated with renal acute tubular necrosis after 24 hours of reperfusion in the fatty, but not in lean rats. Caspase inhibition significantly decreased reperfusion injury in lean animals, but was ineffective in fatty animals. The results indicate that the increased susceptibility of fatty livers to reperfusion injury is associated with a change from an apoptotic form of cell death to necrosis. We conclude that new therapeutic strategies are necessary in the fatty liver. (Hepatology2000;32:1280-1288.)
Diffusion tractography magnetic resonance imaging (MRI) can infer changes in network connectivity in patients with traumatic brain injury (TBI), but the pathological substrates of disconnected tracts ...have not been well defined because of a lack of high-resolution imaging with histopathological validation. We developed an
MRI protocol to analyze tract terminations at 750-μm isotropic resolution, followed by histopathological evaluation of white matter pathology, and applied these methods to a 60-year-old man who died 26 days after TBI. Analysis of 74 cerebral hemispheric white matter regions revealed a heterogeneous distribution of tract disruptions. Associated histopathology identified variable white matter injury with patchy deposition of amyloid precursor protein (APP), loss of neurofilament-positive axonal processes, myelin dissolution, astrogliosis, microgliosis, and perivascular hemosiderin-laden macrophages. Multiple linear regression revealed that tract disruption strongly correlated with the density of APP-positive axonal swellings and neurofilament loss.
diffusion MRI can detect tract disruptions in the human brain that reflect axonal injury.
Autism spectrum disorder (ASD) and obsessive-compulsive disorder (OCD) often share phenotypes of repetitive behaviors, possibly underpinned by abnormal decision-making. To compare neural correlates ...underlying decision-making between these disorders, brain activation of boys with ASD (N = 24), OCD (N = 20) and typically developing controls (N = 20) during gambling was compared, and computational modeling compared performance. Patients were unimpaired on number of risky decisions, but modeling showed that both patient groups had lower choice consistency and relied less on reinforcement learning compared to controls. ASD individuals had disorder-specific choice perseverance abnormalities compared to OCD individuals. Neurofunctionally, ASD and OCD boys shared dorsolateral/inferior frontal underactivation compared to controls during decision-making. During outcome anticipation, patients shared underactivation compared to controls in lateral inferior/orbitofrontal cortex and ventral striatum. During reward receipt, ASD boys had disorder-specific enhanced activation in inferior frontal/insular regions relative to OCD boys and controls. Results showed that ASD and OCD individuals shared decision-making strategies that differed from controls to achieve comparable performance to controls. Patients showed shared abnormalities in lateral-(orbito)fronto-striatal reward circuitry, but ASD boys had disorder-specific lateral inferior frontal/insular overactivation, suggesting that shared and disorder-specific mechanisms underpin decision-making in these disorders. Findings provide evidence for shared neurobiological substrates that could serve as possible future biomarkers.
Cerebral vasospasm continues to be a major cause of poor outcome in patients with ruptured aneurysms. Prophylactic Transluminal Balloon Angioplasty (pTBA) appeared to prevent delayed ischemic ...neurological deficit in a pilot study. A phase II multicenter randomized clinical trial was subsequently designed.
One hundred and seventy patients with Fisher Grade III subarachnoid hemorrhage were enrolled in the study. Of these, 85 patients were randomized to the treatment group and underwent pTBA within 96 hours after subarachnoid hemorrhage. Main end points of the study included the 3-month dichotomized Glasgow Outcome Score (GOS), development of delayed ischemic neurological deficit (DIND), occurrence of Transcranial Doppler (TCD) vasospasm, and length of stay in the ICU and hospital.
The incidence of DIND was lower in the pTBA group (P=0.30) and fewer patients required therapeutic angioplasty to treat DIND (P=0.03). Overall pTBA resulted in an absolute risk reduction of 5.9% and a relative risk reduction of 10.4% unfavorable outcome (P=0.54). Good grade patients had absolute and relative risk reductions of respectively 9.5 and 29.4% (P=0.73). Length of stay in ICU and hospital was similar in both groups. Four patients had a procedure-related vessel perforation, of which three patients died.
While the trial is unsuccessful as defined by the primary end point (GOS), proof of concept is confirmed by these results. Fewer patients tend to develop vasospasm after treatment with pTBA and there is a statistically significantly decreased need for therapeutic angioplasty. pTBA does not improve the poor outcome of patients with Fisher grade III subarachnoid hemorrhage.
More than 75% of patients presenting to level I trauma centers in the United States with suspicion of TBI sufficient to require a clinical computed tomography scan report injury-related symptoms 3 ...months later. There are currently no approved treatments, and few clinical trials have evaluated possible treatments. Efficient trials will require subject inclusion and exclusion criteria that balance cost-effective recruitment with enrolling individuals with a higher chance of benefiting from the interventions. Using data from the
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njury (TRACK-TBI) study, we examined the relationship of 3-month symptoms to pre-injury, demographic, and acute characteristics as well as 2-week symptoms and blood-based biomarkers to identify and evaluate factors that may be used for sample enrichment for clinical trials. Many of the risk factors for TBI symptoms reported in the literature were supported, but the effect sizes of each were small or moderate (< 0.5). The only factors with large effect sizes when predicting 3-month symptom burden were TBI-related (i.e., post-concussive) and post-traumatic stress symptom levels at 2 weeks (respective effect sizes 1.13 and 1.34). TBI severity was not significantly associated with 3-month symptom burden (
= 0.37). Using simulated data to evaluate the effect of enrichment, we showed that including only people with high symptom burden at 2 weeks would permit trials to reduce the sample size by half, with minimal increase in screening, as compared with enrolling an unenriched sample. Clinical trials aimed at reducing symptoms after TBI can be efficiently conducted by enriching the included sample with people reporting a high early symptom burden.
Small-scale coal gasification technology, coupled to a reciprocating engine generator, has the potential for making coal a cost competitive resource for meeting the flexible energy needs and ...resiliency requirements of utilities across the United States. To maintain grid stability and reliability, electrical generation must be regulated to match the load at the proper voltage and frequency. With the expansion of intermittent sources into the grid, such as wind and solar, frequency and voltage regulation become increasingly important and challenging. This work presents the results of a Front End Engineering Design (FEED) effort to detail the engineering and preliminary economics of a small-scale, air blown, fixed-bed gasification process, operating at near-atmospheric pressure, with gas cleanup to provide syngas and pyrolysis liquid fuels for use in reciprocating engine generators for combined heat and power at the University of Alaska Fairbanks. A very detailed assessment of capital and operating costs allows the evaluation of a levelized cost of electricity of 208.06 $/MWh, which can be reduced through the selling of by-products (steam for heating purposes and pyrolysis liquids to be used for power generation in an existing diesel engine). Here, a combined sensitivity analysis, based on the Monte Carlo approach, has been carried out to evaluate the effects of the uncertainties (capital and operating costs and plant annual availability) on the LCOE.
Although both global (brain-general) and regional (tract-specific) variations in cerebral white matter properties have been well documented, research to date has not fully defined their relative ...contribution or their mediational roles in age-related differences in cognition. Towards these goals, we used DTI to collect four measures of white matter: fractional anisotropy (FA), and axial, radial and mean diffusivities (AD, RD, MD) within eight tracts (bilateral superior longitudinal fasciculi SLF, corticospinal tracts CST, optic radiations OR, plus the genu and splenium of the corpus callosum) from 125 participants 18-85 years of age. To assess global versus specific effects, we submitted each DTI measure to principal component analysis (PCA), using the individual tracts as dependent variables. The results yielded two significant components for FA: the first comprised high loadings from the SLF and CST tracts, and the second comprised high loadings from the genu, splenium, and OR tracts. However, variation in AD, RD, and MD was primarily global and yielded a single-component solution in each case. Further analyses suggested that individual differences in these components of the DTI measures do not have a mediational role in the relation between adult age and elementary perceptual speed (digit symbol substitution). However, age was a significant mediator of the relation between the second FA component and perceptual speed. These data suggest that a slowing of perceptual speed is associated with decreasing FA in the genu, splenium, and ORs because the speed-FA relation in these tracts is particularly pronounced for older adults.
There is general agreement that frailty is a state of heightened vulnerability to stressors arising from impairments in multiple systems leading to declines in homeostatic reserve and resiliency, but ...unresolved issues persist about its detection, underlying pathophysiology, and relationship with aging, disability, and multimorbidity. A particularly challenging area is the relationship between frailty and hospitalization. Based on the deliberations of a 2014 Canadian expert consultation meeting and a scoping review of the relevant literature between 2005 and 2015, this discussion paper presents a review of the current state of knowledge on frailty in the acute care setting, including its prevalence and ability to both predict the occurrence and outcomes of hospitalization. The examination of the available evidence highlighted a number of specific clinical and research topics requiring additional study. We conclude with a series of consensus recommendations regarding future research priorities in this important area.
APOL1 risk alleles are associated with increased cardiovascular and chronic kidney disease (CKD) risk. It is unknown whether knowledge of APOL1 risk status motivates patients and providers to attain ...recommended blood pressure (BP) targets to reduce cardiovascular disease.
Multicenter, pragmatic, randomized controlled clinical trial.
6650 individuals with African ancestry and hypertension from 13 health systems.
APOL1 genotyping with clinical decision support (CDS) results are returned to participants and providers immediately (intervention) or at 6 months (control). A subset of participants are re-randomized to pharmacogenomic testing for relevant antihypertensive medications (pharmacogenomic sub-study). CDS alerts encourage appropriate CKD screening and antihypertensive agent use.
Blood pressure and surveys are assessed at baseline, 3 and 6 months. The primary outcome is change in systolic BP from enrollment to 3 months in individuals with two APOL1 risk alleles. Secondary outcomes include new diagnoses of CKD, systolic blood pressure at 6 months, diastolic BP, and survey results. The pharmacogenomic sub-study will evaluate the relationship of pharmacogenomic genotype and change in systolic BP between baseline and 3 months.
To date, the trial has enrolled 3423 participants.
The effect of patient and provider knowledge of APOL1 genotype on systolic blood pressure has not been well-studied. GUARDD-US addresses whether blood pressure improves when patients and providers have this information. GUARDD-US provides a CDS framework for primary care and specialty clinics to incorporate APOL1 genetic risk and pharmacogenomic prescribing in the electronic health record.
ClinicalTrials.govNCT04191824
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