Evaluation of paediatric pulmonary vein stenosis by cardiac CT angiography: a comparative study with transthoracic echocardiography and catheter angiogram.

AIM: To compare prospective electrocardiogram (ECG)-gated cardiac computed tomographic angiography (CCTA) with transthoracic echocardiography (TTE) and cardiac catheter angiography (CCA) for paediatric pulmonary vein (PV) stenosis. MATERIALS AND METHODS: Retrospective chart review was undertaken of all patients who underwent CCTA for PV evaluation over a 4-year period. Patient demographics, findings of CCTA, TTE, and CCA, as well as interventions performed, were recorded for each PV. RESULTS: Thirty-five patients were included (23 male patients). All patients had a prior TTE with time interval between TTE and CCTA ranging from 0 to 90 days. CCTA detected 92 abnormalities in 32 patients. TTE missed 16 PV abnormalities (16/92, 17%), detected 37 abnormalities with certainty (37/92, 40%), and was suggestive in 39 abnormalities (39/92, 42%). CCTA was negative for PV abnormalities when TTE was positive or suspicious in three patients. Nineteen patients underwent CCA (18 patients with 52 abnormalities and one patient with normal PV), confirming CCTA findings. Thirty-nine were treated with angioplasty/stenting (39/52,75%). Failed recanalisation occurred in three PVs (3/52, 6%) and no intervention was attempted for the rest as the gradient was not significant (10/52,19%). Nine patients underwent surgical repair (26/92, 28%). Five patients (14/92, 15%) were managed with no intervention based on CCTA findings and poor clinical prognosis. CONCLUSIONS: CCTA plays an important role in detecting paediatric PV stenosis and identifies additional findings compared to TTE that have direct surgical/interventional implications. CCTA complements TTE in imaging these patients and helps guide management.

The Role of Liver Zonation in Physiology, Regeneration, and Disease.

As blood flows from the portal triad to the central vein, cell-mediated depletion establishes gradients of soluble factors such as oxygen, nutrients, and hormones, which act through molecular pathways (e.g., Wnt/ß-catenin, hedgehog) to spatially regulate hepatocyte functions along the sinusoid. Such "zonation" can lead to the compartmentalized initiation of several liver diseases, including alcoholic/non-alcoholic fatty liver diseases, chemical/drug-induced toxicity, and hepatocellular carcinoma, and can also modulate liver regeneration. Transgenic rodent models provide valuable information on the key molecular regulators of zonation, while in vitro models allow for subjecting cells to precisely controlled factor gradients and elucidating species-specific differences in zonation. Here, we discuss the latest advances in both in vivo and in vitro models of liver zonation and pending questions to be addressed moving forward. Ultimately, obtaining a deeper understanding of zonation can lead to the development of more effective therapeutics for liver diseases, microphysiological systems, and scalable cell-based therapies.

Key Characteristics of Human Hepatotoxicants as a Basis for Identification and Characterization of the Causes of Liver Toxicity.

Hazard identification regarding adverse effects on the liver is a critical step in safety evaluations of drugs and other chemicals. Current testing paradigms for hepatotoxicity rely heavily on preclinical studies in animals and human data (epidemiology and clinical trials). Mechanistic understanding of the molecular and cellular pathways that may cause or exacerbate hepatotoxicity is well advanced and holds promise for identification of hepatotoxicants. One of the challenges in translating mechanistic evidence into robust decisions about potential hepatotoxicity is the lack of a systematic approach to integrate these data to help identify liver toxicity hazards. Recently, marked improvements were achieved in the practice of hazard identification of carcinogens, female and male reproductive toxicants, and endocrine disrupting chemicals using the key characteristics approach. Here, we describe the methods by which key characteristics of human hepatotoxicants were identified and provide examples for how they could be used to systematically identify, organize, and use mechanistic data when identifying hepatotoxicants.

Activity Levels and Outcomes of a Standalone Regional Paediatric High Dependency Unit.

Aim The Paediatric High Dependency Unit (PHDU) at University Hospital Limerick (UHL) operates as the only standalone unit outside of Dublin centres. The aim of this study was to describe a regional PHDU population, compare outcomes with international standards (PICANet) and ensure adequate clinical governance. Methods This is a retrospective analysis of 126 admission records from January - December 2019. Results There were 126 admissions to PHDU in 2019, of which respiratory (n=81, 64.3%) and neurological (n=23, 18.3%) subgroups represented the largest populations. Median length of stay was two days with mean age of admission 3.97 ± 4.5 years and slightly more male admissions (56%). Of the total, 65% required oxygen, 32.1% needed CPAP directly and 38% commenced high-flow, of whom 29% transitioned to CPAP. Transfer for tertiary care was required in 10.3%, of whom 7.9% needed PICU. Conclusion The data show UHL PHDU to have a patient population reflecting international trends as well as producing satisfactory patient outcomes. With a low rate of transfer for tertiary care and given that 15 other paediatric units exist in the Republic of Ireland outside Dublin, development of regional PHDU capacity would provide great opportunity to decrease strain on PICU bed capacity, particularly during busy Winter months.

Bioengineered Liver Models for Investigating Disease Pathogenesis and Regenerative Medicine.

Owing to species-specific differences in liver pathways, in vitro human liver models are utilized for elucidating mechanisms underlying disease pathogenesis, drug development, and regenerative medicine. To mitigate limitations with de-differentiated cultures, bioengineers have developed advanced techniques/platforms, including micropatterned cocultures, spheroids/organoids, bioprinting, and microfluidic devices, for perfusing cell cultures and liver slices. Such techniques improve mature functions and culture lifetime of primary and stem-cell human liver cells. Furthermore, bioengineered liver models display several features of liver diseases including infections with pathogens (e.g., malaria, hepatitis C/B viruses, Zika, dengue, yellow fever), alcoholic/nonalcoholic fatty liver disease, and cancer. Here, we discuss features of bioengineered human liver models, their uses for modeling aforementioned diseases, and how such models are being augmented/adapted for fabricating implantable human liver tissues for clinical therapy. Ultimately, continued advances in bioengineered human liver models have the potential to aid the development of novel, safe, and efficacious therapies for liver disease.

Baseline factors associated with early and late death in intracerebral haemorrhage survivors.

BACKGROUND AND PURPOSE: The aim of this study was to determine whether early and late death are associated with different baseline factors in intracerebral haemorrhage (ICH) survivors. METHODS: This was a secondary analysis of the multicentre prospective observational CROMIS-2 ICH study. Death was defined as 'early' if occurring within 6 months of study entry and 'late' if occurring after this time point. RESULTS: In our cohort (n = 1094), there were 306 deaths (per 100 patient-years: absolute event rate, 11.7; 95% confidence intervals, 10.5-13.1); 156 were 'early' and 150 'late'. In multivariable analyses, early death was independently associated with age [per year increase; hazard ratio (HR), 1.05, P = 0.003], history of hypertension (HR, 1.89, P = 0.038), pre-event modified Rankin scale score (per point increase; HR, 1.41, P < 0.0001), admission National Institutes of Health Stroke Scale score (per point increase; HR, 1.11, P < 0.0001) and haemorrhage volume >60 mL (HR, 4.08, P < 0.0001). Late death showed independent associations with age (per year increase; HR, 1.04, P = 0.003), pre-event modified Rankin scale score (per point increase; HR, 1.42, P = 0.001), prior anticoagulant use (HR, 2.13, P = 0.028) and the presence of intraventricular extension (HR, 1.73, P = 0.033) in multivariable analyses. In further analyses where time was treated as continuous (rather than dichotomized), the HR of previous cerebral ischaemic events increased with time, whereas HRs for Glasgow Coma Scale score, National Institutes of Health Stroke Scale score and ICH volume decreased over time. CONCLUSIONS: We provide new evidence that not all baseline factors associated with early mortality after ICH are associated with mortality after 6 months and that the effects of baseline variables change over time. Our findings could help design better prognostic scores for later death after ICH.

Frequency, characteristics, and clinical determinants of 'prodrome' in familial Mediterranean fever patients.

Objective: Prodrome is defined by manifestations that precede a familial Mediterranean fever (FMF) attack and predict its emergence. We aimed to determine the frequency, characteristics, and clinical determinants of prodrome in patients with FMF.Method: This cross-sectional study was conducted in a tertiary rheumatology clinic. During the clinical interview, all patients completed a standardized questionnaire about the pre-attack period. Prodrome was defined as the presence of any recurrent pre-attack manifestation occurring at least 4 h before an attack. Patients were classified according to whether they had prodrome of any kind of attack.Results: The study enrolled 401 patients aged 37.7 ± 11.0 years (mean ± sd). Male gender, M694V/M694V, homozygous MEFV mutation, peritonitis, pleuritis, and arthritis were more frequent in prodrome-positive patients. Altogether, 141 patients (35.2%) had prodrome. Male gender and ever having attack types of peritonitis or arthritis were independent clinical determinants of prodrome [relative risk (95% confidence interval): 1.72 (1.07-2.76), p = 0.02; 4.27 (1.80-10.1), p = 0.001; 1.77 (1.04-3.04), p = 0.04, respectively]. Age, MEFV mutations, pleuritis, and erysipelas-like erythema were not clinical determinants.Conclusions: All FMF patients, particularly males and patients who had peritonitis or arthritis at any time, should be questioned about prodrome. Prodrome should be analysed in terms of elucidating the pathogenesis of FMF and as an opportunity for a secondary prevention strategy for impending attacks. This study may shed light on prodrome for future cytokine or drug studies with the purpose of developing new cost-effective treatment protocols irrespective of colchicine resistance.

Diabetes mellitus and colorectal carcinoma outcomes: a meta-analysis.

OBJECTIVES: The impact of diabetes mellitus (DM) on colorectal cancer (CRC) outcomes remains unknown. We studied this by conducting a meta-analysis to evaluate (1) CRC outcomes with and without DM and (2) treatment patterns. METHODS: We searched PubMed, EMBASE, Google Scholar, and CINAHL for full-text English studies from 1970 to 12/31/2017. We searched keywords, subject headings, and MESH terms to locate studies of CRC outcomes/treatment and DM. Studies were evaluated by two oncologists. Of 14,332, 48 met inclusion criteria. In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses method, we extracted study location, design, DM definition, covariates, comparison groups, outcomes, and relative risks and/or hazard ratios. We utilized a random-effects model to pool adjusted risk estimates. Primary outcomes were all-cause mortality (ACM), disease-free survival (DFS), relapse-free survival (RFS), and cancer-specific survival (CSS). The secondary outcome was treatment patterns. RESULTS: Forty-eight studies were included, 42 in the meta-analysis, and 6 in the descriptive analysis, totaling > 240,000 patients. ACM was 21% worse (OR 1.21, 95% CI 1.15-1.28) and DFS was 75% worse (OR 1.75, 95% CI: 1.33-2.31) in patients with DM. No differences were detected in CSS (OR 1.10, 95% CI 0.98-1.23) or RFS (OR 1.12, 95% CI 0.91-1.38). Descriptive analysis of treatment patterns in CRC and DM suggested potentially less adjuvant therapy use in cases with DM and CRC. CONCLUSIONS: Our meta-analysis suggests that patients with CRC and DM have worse ACM and DFS than patients without DM, suggesting that non-cancer causes of death in may account for worse outcomes.

Meeting the Challenge of Predicting Hepatic Clearance of Compounds Slowly Metabolized by Cytochrome P450 Using a Novel Hepatocyte Model, HepatoPac.

Generating accurate in vitro intrinsic clearance data is an important aspect of predicting in vivo human clearance. Primary hepatocytes in suspension are routinely used to predict in vivo clearance; however, incubation times have typically been limited to 4-6 hours, which is not long enough to accurately evaluate the metabolic stability of slowly metabolized compounds. HepatoPac is a micropatterened hepatocyte-fibroblast coculture system that can be used for continuous incubations of up to 7 days. This study evaluated the ability of human HepatoPac to predict the in vivo clearance (CL) of 17 commercially available compounds with low to intermediate clearance (<12 ml/min/kg). In vitro half-life for disappearance of each compound was converted to hepatic clearance using the well stirred model, with and without correction for plasma protein binding. Hepatic CL, using three individual donors, was accurately predicted for 11 of 17 compounds (59%; predicted clearance within 2-fold of observed human in vivo clearance values). The accuracy of prediction increased to 82% (14 of 17 compounds) with an acceptance criterion defined as within 3-fold. When considering only low clearance compounds (<5 ml/min per kg), which represented 10 of the 17 compounds, the accuracy of prediction was 70% within 2-fold and 100% within 3-fold. In addition, the turnover of three slowly metabolized compounds (alprazolam, meloxicam, and tolbutamide) in HepatoPac was directly compared with turnover in suspended hepatocytes. The turnover of alprazolam and tolbutamide was approximately 2-fold greater using HepatoPac compared with suspended hepatocytes, which was roughly in line with the extrapolated values (correcting for the longer incubation time and lower cell number with HepatoPac). HepatoPac, but not suspended hepatocytes, demonstrated significant turnover of meloxicam. These results demonstrate the utility of HepatoPac for prediction of in vivo hepatic clearance, particularly with low clearance compounds.

Chronic inflammation in adult familial Mediterranean fever patients: underlying causes and association with amyloidosis.

Background: Chronic inflammation, as determined by persistently elevated acute-phase reactants in attack-free periods, can occasionally be observed in patients with familial Mediterranean fever (FMF) and is suggested to be a risk factor for the development of amyloidosis. We aimed to investigate the underlying causes of chronic inflammation in FMF patients and its association with amyloidosis in long-term follow-up. Method: Electronic medical records of FMF patients who had regular follow-up for ≥ 5 years in our cohort were utilized. As part of routine evaluation, detailed history, physical examination, and pertinent laboratory and radiographic investigations were performed in all patients to determine potential causes of elevated C-reactive protein (CRP) levels. Results: The study included 146 FMF patients who had no evidence of amyloidosis at baseline and had regular follow-up for ≥ 5 years. Thirty-seven patients (25.3%) were found to have chronic inflammation in the disease course. Twenty-five (67.5%) of them had either very frequent attacks or chronic manifestations of disease. In the entire study group, amyloidosis developed in five patients (3.42%) during the 5 year follow-up, four in the FMF with chronic inflammation group (10.8%), and only one of the 109 patients without chronic inflammation (odds ratio 13.09, 95% confidence interval 1.41-121.2). Conclusions: The results suggest that persistently high CRP levels during the attack-free periods may be a strong risk factor for the development of amyloidosis in patients with FMF. The vast majority of FMF patients with chronic inflammation had active FMF.

Advances in Engineered Human Liver Platforms for Drug Metabolism Studies.

Metabolism in the liver often determines the overall clearance rates of many pharmaceuticals. Furthermore, induction or inhibition of the liver drug metabolism enzymes by perpetrator drugs can influence the metabolism of victim drugs (drug-drug interactions). Therefore, determining liver-drug interactions is critical during preclinical drug development. Unfortunately, studies in animals are often of limited value because of significant differences in the metabolic pathways of the liver across different species. To mitigate such limitations, the pharmaceutical industry uses a continuum of human liver models, ranging from microsomes to transfected cell lines and cultures of primary human hepatocytes (PHHs). Of these models, PHHs provide a balance of high-throughput testing capabilities together with a physiologically relevant cell type that exhibits all the characteristic enzymes, cofactors, and transporters. However, PHH monocultures display a rapid decline in metabolic capacity. Consequently, bioengineers have developed several tools, such as cellular microarrays, micropatterned cocultures, self-assembled and bioprinted spheroids, and perfusion devices, to enhance and stabilize PHH functions for ≥2 weeks. Many of these platforms have been validated for drug studies, whereas some have been adapted to include liver nonparenchymal cells that can influence hepatic drug metabolism in health and disease. Here, we focus on the design features of such platforms and their representative drug metabolism validation datasets, while discussing emerging trends. Overall, the use of engineered human liver platforms in the pharmaceutical industry has been steadily rising over the last 10 years, and we anticipate that these platforms will become an integral part of drug development with continued commercialization and validation for routine screening use.

Discontinuation and non-publication of neurodegenerative disease trials: a cross-sectional analysis.

BACKGROUND AND PURPOSE: Trial discontinuation and non-publication represent major sources of research waste in clinical medicine. No previous studies have investigated non-dissemination bias in clinical trials of neurodegenerative diseases. METHODS: ClinicalTrials.gov was searched for all randomized, interventional, phase II-IV trials that were registered between 1 January 2000 and 31 December 2009 and included adults with Alzheimer's disease, motor neurone disease, multiple sclerosis or Parkinson's disease. Publications from these trials were identified by extensive online searching and contact with authors, and multiple logistic regression analysis was performed to identify characteristics associated with trial discontinuation and non-publication. RESULTS: In all, 362 eligible trials were identified, of which 12% (42/362) were discontinued. 28% (91/320) of completed trials remained unpublished after 5 years. Trial discontinuation was independently associated with number of patients (P = 0.015; more likely in trials with ≤100 patients; odds ratio 2.65, 95% confidence interval 1.21-5.78) and phase of trial (P = 0.009; more likely in phase IV than phase III trials; odds ratio 3.90, 95% confidence interval 1.41-10.83). Trial non-publication was independently associated with blinding status (P = 0.005; more likely in single-blind than double-blind trials; odds ratio 5.63, 95% confidence interval 1.70-18.71), number of centres (P = 0.010; more likely in single-centre than multi-centre trials; odds ratio 2.49, 95% confidence interval 1.25-4.99), phase of trial (P = 0.041; more likely in phase II than phase IV trials; odds ratio 2.88, 95% confidence interval 1.04-7.93) and sponsor category (P = 0.001; more likely in industry-sponsored than university-sponsored trials; odds ratio 5.05, 95% confidence interval 1.87-13.63). CONCLUSIONS: There is evidence of non-dissemination bias in randomized trials of interventions for neurodegenerative diseases. Associations with trial discontinuation and non-publication were similar to findings in other diseases. These biases may distort the therapeutic information available to inform clinical practice.

Hepatitis C virus infection induces autocrine interferon signaling by human liver endothelial cells and release of exosomes, which inhibits viral replication.

BACKGROUND & AIMS: Liver sinusoidal endothelial cells (LSECs) make up a large proportion of the nonparenchymal cells in the liver. LSECs are involved in induction of immune tolerance, but little is known about their functions during hepatitis C virus (HCV) infection. METHODS: Primary human LSECs (HLSECs) and immortalized liver endothelial cells (TMNK-1) were exposed to various forms of HCV, including full-length transmitted/founder virus, sucrose-purified Japanese fulminant hepatitis-1 (JFH-1), a virus encoding a luciferase reporter, and the HCV-specific pathogen-associated molecular pattern molecules. Cells were analyzed by confocal immunofluorescence, immunohistochemical, and polymerase chain reaction assays. RESULTS: HLSECs internalized HCV, independent of cell-cell contacts; HCV RNA was translated but not replicated. Through pattern recognition receptors (Toll-like receptor 7 and retinoic acid-inducible gene 1), HCV RNA induced consistent and broad transcription of multiple interferons (IFNs); supernatants from primary HLSECs transfected with HCV-specific pathogen-associated molecular pattern molecules increased induction of IFNs and IFN-stimulated genes in HLSECs. Recombinant type I and type III IFNs strongly up-regulated HLSEC transcription of IFN λ3 (IFNL3) and viperin (RSAD2), which inhibit replication of HCV. Compared with CD8(+) T cells, HLSECs suppressed HCV replication within Huh7.5.1 cells, also inducing IFN-stimulated genes in co-culture. Conditioned media from IFN-stimulated HLSECs induced expression of antiviral genes by uninfected primary human hepatocytes. Exosomes, derived from HLSECs after stimulation with either type I or type III IFNs, controlled HCV replication in a dose-dependent manner. CONCLUSIONS: Cultured HLSECs produce factors that mediate immunity against HCV. HLSECs induce self-amplifying IFN-mediated responses and release of exosomes with antiviral activity.

Enhancing the functional maturity of induced pluripotent stem cell-derived human hepatocytes by controlled presentation of cell-cell interactions in vitro.

UNLABELLED: Induced pluripotent stem cell-derived human hepatocyte-like cells (iHeps) could provide a powerful tool for studying the mechanisms underlying human liver development and disease, testing the efficacy and safety of pharmaceuticals across different patients (i.e., personalized medicine), and enabling cell-based therapies in the clinic. However, current in vitro protocols that rely upon growth factors and extracellular matrices (ECMs) alone yield iHeps with low levels of liver functions relative to adult primary human hepatocytes (PHHs). Moreover, these low hepatic functions in iHeps are difficult to maintain for prolonged times (weeks to months) in culture. Here, we engineered a micropatterned coculture (iMPCC) platform in a multiwell format that, in contrast to conventional confluent cultures, significantly enhanced the functional maturation and longevity of iHeps in culture for at least 4 weeks in vitro when benchmarked against multiple donors of PHHs. In particular, iHeps were micropatterned onto collagen-coated domains of empirically optimized dimensions, surrounded by 3T3-J2 murine embryonic fibroblasts, and then sandwiched with a thin layer of ECM gel (Matrigel). We assessed iHep maturity by global gene expression profiles, hepatic polarity, secretion of albumin and urea, basal cytochrome P450 (CYP450) activities, phase II conjugation, drug-mediated CYP450 induction, and drug-induced hepatotoxicity. CONCLUSION: Controlling both homotypic interactions between iHeps and heterotypic interactions with stromal fibroblasts significantly matures iHep functions and maintains them for several weeks in culture. In the future, iMPCCs could prove useful for drug screening, studying molecular mechanisms underlying iHep differentiation, modeling liver diseases, and integration into human-on-a-chip systems being designed to assess multiorgan responses to compounds.

Prediction of Drug Clearance and Drug-Drug Interactions in Microscale Cultures of Human Hepatocytes.

Accurate prediction of in vivo hepatic drug clearance using in vitro assays is important to properly estimate clinical dosing regimens. Clearance of low-turnover compounds is especially difficult to predict using short-lived suspensions of unpooled primary human hepatocytes (PHHs) and functionally declining PHH monolayers. Micropatterned cocultures (MPCCs) of PHHs and 3T3-J2 fibroblasts have been shown previously to display major liver functions for several weeks in vitro. In this study, we first characterized long-term activities of major cytochrome P450 enzymes in MPCCs created from unpooled cryopreserved PHH donors. MPCCs were then used to predict the clearance of 26 drugs that exhibit a wide range of turnover rates in vivo (0.05-19.5 ml/min per kilogram). MPCCs predicted 73, 92, and 96% of drug clearance values for all tested drugs within 2-fold, 3-fold, and 4-fold of in vivo values, respectively. There was good correlation (R(2) = 0.94, slope = 1.05) of predictions between the two PHH donors. On the other hand, suspension hepatocytes and conventional monolayers created from the same donor had significantly reduced predictive capacity (i.e., 30-50% clearance values within 4-fold of in vivo), and were not able to metabolize several drugs. Finally, we modulated drug clearance in MPCCs by inducing or inhibiting P450s. Rifampin-mediated CYP3A4 induction increased midazolam clearance by 73%, while CYP3A4 inhibition with ritonavir decreased midazolam clearance by 79%. Similarly, quinidine-mediated CYP2D6 inhibition reduced clearance of dextromethorphan and desipramine by 71 and 22%, respectively. In conclusion, MPCCs created using cryopreserved unpooled PHHs can be used for drug clearance predictions and to model drug-drug interactions.

Early Magnesium Treatment After Aneurysmal Subarachnoid Hemorrhage: Individual Patient Data Meta-Analysis.

BACKGROUND AND PURPOSE: Delayed cerebral ischemia (DCI) is an important cause of poor outcome after aneurysmal subarachnoid hemorrhage (SAH). Trials of magnesium treatment starting <4 days after symptom onset found no effect on poor outcome or DCI in SAH. Earlier installment of treatment might be more effective, but individual trials had not enough power for such a subanalysis. We performed an individual patient data meta-analysis to study whether magnesium is effective when given within different time frames within 24 hours after the SAH. METHODS: Patients were divided into categories according to the delay between symptom onset and start of the study medication: <6, 6 to 12, 12 to 24, and >24 hours. We calculated adjusted risk ratios with corresponding 95% confidence intervals for magnesium versus placebo treatment for poor outcome and DCI. RESULTS: We included 5 trials totaling 1981 patients; 83 patients started treatment<6 hours. For poor outcome, the adjusted risk ratios of magnesium treatment for start <6 hours were 1.44 (95% confidence interval, 0.83-2.51); for 6 to 12 hours 1.03 (0.65-1.63), for 12 to 24 hours 0.84 (0.65-1.09), and for >24 hours 1.06 (0.87-1.31), and for DCI, <6 hours 1.76 (0.68-4.58), for 6 to 12 hours 2.09 (0.99-4.39), for 12 to 24 hours 0.80 (0.56-1.16), and for >24 hours 1.08 (0.88-1.32). CONCLUSIONS: This meta-analysis suggests no beneficial effect of magnesium treatment on poor outcome or DCI when started early after SAH onset. Although the number of patients was small and a beneficial effect cannot be definitively excluded, we found no justification for a new trial with early magnesium treatment after SAH.

Dynamical System Modeling of Immune Reconstitution after Allogeneic Stem Cell Transplantation Identifies Patients at Risk for Adverse Outcomes.

Systems that evolve over time and follow mathematical laws as they evolve are called dynamical systems. Lymphocyte recovery and clinical outcomes in 41 allograft recipients conditioned using antithymocyte globulin (ATG) and 4.5-Gy total body irradiation were studied to determine if immune reconstitution could be described as a dynamical system. Survival, relapse, and graft-versus-host disease (GVHD) were not significantly different in 2 cohorts of patients receiving different doses of ATG. However, donor-derived CD3(+) cell reconstitution was superior in the lower ATG dose cohort, and there were fewer instances of donor lymphocyte infusion (DLI). Lymphoid recovery was plotted in each individual over time and demonstrated 1 of 3 sigmoid growth patterns: Pattern A (n = 15) had rapid growth with high lymphocyte counts, pattern B (n = 14) had slower growth with intermediate recovery, and pattern C (n = 10) had poor lymphocyte reconstitution. There was a significant association between lymphocyte recovery patterns and both the rate of change of donor-derived CD3(+) at day 30 after stem cell transplantation (SCT) and clinical outcomes. GVHD was observed more frequently with pattern A, relapse and DLI more so with pattern C, with a consequent survival advantage in patients with patterns A and B. We conclude that evaluating immune reconstitution after SCT as a dynamical system may differentiate patients at risk of adverse outcomes and allow early intervention to modulate that risk.

Establishment of a hepatocyte-kupffer cell coculture model for assessment of proinflammatory cytokine effects on metabolizing enzymes and drug transporters.

Elevated levels of proinflammatory cytokines associated with infection and inflammation can modulate cytochrome P450 enzymes, leading to potential disease-drug interactions and altered small-molecule drug disposition. We established a human-derived hepatocyte-Kupffer cell (Hep:KC) coculture model to assess the indirect cytokine impact on hepatocytes through stimulation of KC-mediated cytokine release and compared this model with hepatocytes alone. Characterization of Hep:KC cocultures showed an inflammation response after treatment with lipopolysaccharide and interleukin (IL)-6 (indicated by secretion of various cytokines). Additionally, IL-6 exposure upregulated acute-phase proteins (C-reactive protein, alpha-1-acid glycoprotein, and serum amyloid A2) and downregulated CYP3A4. Compared with hepatocytes alone, Hep:KC cocultures showed enhanced IL-1ß-mediated effects but less impact from both IL-2 and IL-23. Hep:KC cocultures treated with IL-1ß exhibited a higher release of proinflammatory cytokines, an increased upregulation of acute-phase proteins, and a larger extent of metabolic enzyme and transporter suppression. IC50 values for IL-1ß-mediated CYP3A4 suppression were lower in Hep:KC cocultures (98.0-144 pg/ml) compared with hepatocytes alone (IC50 > 5000 pg/ml). Cytochrome suppression was preventable by blocking IL-1ß interaction with IL-1R1 using an antagonist cytokine or an anti-IL-1ß antibody. Unlike IL-1ß, IL-6-mediated effects were comparable between hepatocyte monocultures and Hep:KC cocultures. IL-2 and IL-23 caused a negligible inflammation response and a minimal inhibition of CYP3A4. In both hepatocyte monocultures and Hep:KC cocultures, IL-2RB and IL-23R were undetectable, whereas IL-6R and IL-1R1 levels were higher in Hep:KC cocultures. In summary, compared with hepatocyte monocultures, the Hep:KC coculture system is a more robust in vitro model for studying the impact of proinflammatory cytokines on metabolic enzymes.