Quasinormal Modes of Optical Solitons.

Quasinormal modes (QNMs) are essential for understanding the stability and resonances of open systems, with increasing prominence in black hole physics. We present here the first study of QNMs of optical potentials. We show that solitons can support QNMs, deriving a soliton perturbation equation and giving exact analytical expressions for the QNMs of fiber solitons. We discuss the boundary conditions in this intrinsically dispersive system and identify novel signatures of dispersion. From here, we discover a new analogy with black holes and describe a regime in which the soliton is a robust black hole simulator for light-ring phenomena. Our results invite a range of applications, from the description of optical pulse propagation with QNMs to the use of state-of-the-art technology from fiber optics to address questions in black hole physics, such as QNM spectral instabilities and the role of nonlinearities in ringdown.

The inexorable increase of biologic exposure in paediatric inflammatory bowel disease: a Scottish, population-based, longitudinal study.

BACKGROUND: The use of biologics in paediatric-onset inflammatory bowel disease (PIBD) is rapidly changing. AIMS: To identify the incidence and prevalence of biologic use within Scottish PIBD services, and to describe patient demographics and outcomes for those patients who required escalation of therapy beyond anti-tumour necrosis factor alpha (anti-TNFα) agents METHODS: We captured a nationwide cohort of prospectively identified patients less than 18 years of age with PIBD (A1 phenotype; diagnosed <17 years of age) within paediatric services over a 4.5-year period (1 January 2015-30 June 2019). All patients who received infliximab, adalimumab, vedolizumab or ustekinumab during the study period and/or received their first dose of these biologics were audited retrospectively. RESULTS: Scotland-wide PIBD-prevalence cases increased from 554 to 644 over the study period. A total of 495 incident new-start biological therapies were commenced on 403 PIBD patients: 295 infliximab (60%), 161 adalimumab (32%), 24 vedolizumab (5%) and 15 ustekunumab (3%). The proportion of new-start biologics changed with infliximab initiation rates decreasing (87%-54%) while adalimumab (13%-31%), vedolizumab (0%-9%) and ustekinumab (0%-6%) all increased. The incidence rate (first dose of new biologic not including biosimilar switch) increased from 6.9% to 8.1% over the study period and point prevalence rates (any biologic use) increased from 20.2% to 43.5% - an average annual percentage increase of 20%. Biosimilar penetration of new-start anti-TNFα agents increased from 3% to 91%. Demographics and outcomes of those patients receiving vedolizumab and ustekinumab were similar. CONCLUSIONS: Complete accrual of Scottish nationwide biologic usage within paediatric services demonstrates a rapidly changing, inexorably increasing PIBD biologics landscape.

Prematurity, Delivery Method, and Infant Feeding Type Are Not Associated with Paediatric-onset Inflammatory Bowel Disease Risk: A Scottish Retrospective Birth Cohort Study.

BACKGROUND AND AIMS: The incidence of paediatric-onset inflammatory bowel disease [PIBD] continues to rise globally. We aimed to determine whether mode of delivery, gestational age at birth, or type of infant feeding contribute to the development of PIBD in a nationwide cohort of Scottish children. METHODS: All children born in Scotland between 1981 and 2017 were identified using linked health administrative data to determine mode of delivery, gestational age at birth, and type of infant feeding. PIBD cases were defined as onset of Crohn's disease [CD], ulcerative colitis [UC], or IBD-unclassified [IBDU] before age 16 years. Validation was performed within an entire Scottish health board [16% of total population] via individual case-note verification. Hazard ratios [HR] were calculated for each exposure using Cox proportional hazards models. RESULTS: A study population of 2 013 851 children was identified including 1721 PIBD cases. Validation of 261 PIBD patients coded as CD and/or UC identified 242 [93%] as true positive. Children delivered vaginally did not have an altered risk of developing PIBD compared with those delivered by caesarean section, adjusted HR 0.95 [95% CI 0.84-1.08] [p = 0.46]. Compared with children born at term [≥37 weeks], children born prematurely did not have an altered risk of developing PIBD, i.e., at 24-31 weeks of gestation, HR 0.99 [95% CI 0.57-1.71] [p = 0.97] and at 32-36 weeks of gestation, HR 0.96 [95% CI 0.76-1.20] [p = 0.71]. Compared with children exclusively breastfed at age 6 weeks, children exclusively formula fed did not have an altered risk of developing PIBD: adjusted HR 0.97 [95% CI 0.81-1.15] [p = 0.69]. CONCLUSIONS: This population-based study demonstrates no association between mode of delivery, gestational age, or exclusive formula feeding at 6 weeks, and the development of PIBD.

Recognising and Treating Complicated Fissuring Perianal Crohn Disease: A South-East Scotland Cohort Study.

ABSTRACT: Fissuring perianal Crohn disease (CD) is not recognised as a perianal phenotype in Montreal/Paris inflammatory bowel disease classifications; however, can occasionally present as complicated disease with severe perianal pain driving increasingly intensive medical therapy despite well controlled luminal disease. We identified a regional cohort of prospectively acquired incident cases of paediatric CD diagnosed <16 years of age in South-East Scotland over a 19-year period (1999-2018), and conducted a retrospective review of complicated fissuring perianal CD causing severe pain related to anal sphincter complex spasm at defecation. Two hundred forty-seven new cases of paediatric CD were diagnosed with complicated fissuring perianal disease identified in 4 described cases (cumulative incidence 1.6%). These patients with marked fissuring and refractory anal sphincter complex spasm required neurostimulation-guided, 4-quadrant, anal intrasphincteric botulinum toxin (BT). All experienced immediate success, measured by cessation of spasms, with variable ongoing symptom relief after median (range) 3 (2-5) BT injections.

Paediatric Patients (Less Than Age of 17 Years) Account for Less Than 1.5% of All Prevalent Inflammatory Bowel Disease Cases.

The prevalence of inflammatory bowel disease (IBD) continues to rise globally; however, the true proportion of paediatric IBD patients remains unknown. We conducted an all-age, multiparameter, population-based search using capture-recapture methodology to identify all IBD cases to August 31, 2018 within Lothian, a defined health board and the largest of the 3 within South-East Scotland. Individual case note validation was performed for all 24,601 possible IBD cases according to internationally recognised diagnostic and age criteria. Of 7035 confirmed point-prevalent patients, 560 were classified as A1 age phenotype at diagnosis, constituting just 8% of all cases. Ninety-nine patients were less than 17 years of age on August 31, 2018, constituting only 1.4% of all point-prevalent cases. These results demonstrate the true contemporary proportion of prevalent paediatric IBD patients is strikingly low, reflecting compounding prevalence in adult practice and the near-normal life expectancy of this chronic, incurable condition.

Rigbox: An Open-Source Toolbox for Probing Neurons and Behavior.

Setting up an experiment in behavioral neuroscience is a complex process that is often managed with ad hoc solutions. To streamline this process, we developed Rigbox, a high-performance, open-source software toolbox that facilitates a modular approach to designing experiments (https://github.com/cortex-lab/Rigbox). Rigbox simplifies hardware input-output, time aligns datastreams from multiple sources, communicates with remote databases, and implements visual and auditory stimuli presentation. Its main submodule, Signals, allows intuitive programming of behavioral tasks. Here we illustrate its function with the following two interactive examples: a human psychophysics experiment, and the game of Pong. We give an overview of running experiments in Rigbox, provide benchmarks, and conclude with a discussion on the extensibility of the software and comparisons with similar toolboxes. Rigbox runs in MATLAB, with Java components to handle network communication, and a C library to boost performance.

IBD prevalence in Lothian, Scotland, derived by capture-recapture methodology.

OBJECTIVE: IBD prevalence is estimated to be rising, but no detailed, recent UK data are available. The last reported prevalence estimate in the UK was 0.40% in 2003. We aimed to establish the current, and project future, prevalence in Lothian, Scotland. DESIGN: We conducted an all-age multiparameter search strategy using inpatient IBD international classification of disease (ICD-10) coding (K50/51)(1997-2018), IBD pathology coding (1990-2018), primary and secondary care prescribing data (2009-2018) and a paediatric registry, (1997-2018) to identify 'possible' IBD cases up to 31/08/2018. Diagnoses were manually confirmed through electronic health record review as per Lennard-Jones/Porto criteria. Autoregressive integrated moving average (ARIMA) regression was applied to forecast prevalence to 01/08/2028. RESULTS: In total, 24 601 possible IBD cases were identified of which 10 499 were true positives. The point prevalence for IBD in Lothian on 31/08/2018 was 784/100 000 (UC 432/100 000, Crohn's disease 284/100 000 and IBD unclassified (IBDU) 68/100 000). Capture-recapture methods identified an additional 427 'missed' cases (95% CI 383 to 477) resulting in a 'true' prevalence of 832/100 000 (95% CI 827 to 837).Prevalence increased by 4.3% per year between 2008 and 2018 (95% CI +3.7 to +4.9%, p<0.0001). ARIMA modelling projected a point prevalence on 01/08/2028 of 1.02% (95% CI 0.97% to 1.07%) that will affect an estimated 1.53% (95% CI 1.37% to 1.69%) of those >80 years of age. CONCLUSIONS: We report a rigorously validated IBD cohort with all-age point prevalence on 31/08/2018 of 1 in 125, one of the highest worldwide.

Incidence of Paediatric Stricturing Duodenal Crohn Disease: A 19-Year Population-based Cohort Study.

OBJECTIVES: Stricturing duodenal Crohn disease (CD) is a rare but serious presentation of CD causing significant morbidity. We aim to provide the first robust incidence data and case studies on this severe presentation in children. METHODS: A regional cohort of prospectively acquired incident cases of paediatric CD diagnosed <16 years of age in South-East Scotland was captured over a 19-year period (1999-2018). A retrospective review was conducted on the medical records of all patients together with a review of the available literature and consensus guidelines. Incidence rates for all CD and for duodenal stricturing CD were calculated. RESULTS: A total of 247 new cases of paediatric CD were diagnosed within the study period. Median age at diagnosis was 12.5 years with 62% male predominance. Overall paediatric CD incidence rate was 5.70/100,000/year with a specific duodenal B2 phenotype disease incidence rate of 0.05/100,000/year; representing 0.8% of incident cases at diagnosis. Two incident cases of stricturing duodenal CD presented with systemic symptoms of weight loss, abdominal pain, anorexia, and lethargy, together with persistent vomiting suggestive of obstruction. Both cases partially responded to intensive medical therapy but eventually required laparoscopic gastroduodenostomy. A detailed literature search confirmed there are no paediatric incidence data, guidelines, or case reports relating to duodenal stricture as either a presentation or complication of CD. CONCLUSIONS: Duodenal structuring disease is a rare but serious presentation of CD causing significant morbidity and not currently covered in the paediatric literature or consensus guidelines. Best practice medical and surgical management remain uncertain and require further research.

Cortical State Fluctuations across Layers of V1 during Visual Spatial Perception.

Many factors modulate the state of cortical activity, but the importance of cortical state variability for sensory perception remains debated. We trained mice to detect spatially localized visual stimuli and simultaneously measured local field potentials and excitatory and inhibitory neuron populations across layers of primary visual cortex (V1). Cortical states with low spontaneous firing and correlations in excitatory neurons, and suppression of 3- to 7-Hz oscillations in layer 4, accurately predicted single-trial visual detection. Our results show that cortical states exert strong effects at the initial stage of cortical processing in V1 and can play a prominent role for visual spatial behavior in mice.

Mineral Surfaces as Agents of Environmental Proteolysis: Mechanisms and Controls.

We investigated the extent to which contact with mineral surfaces affected the molecular integrity of a model protein, with an emphasis on identifying the mechanisms (hydrolysis, oxidation) and conditions leading to protein alteration. To this end, we studied the ability of four mineral surface archetypes (negatively charged, positively charged, neutral, redox-active) to abiotically fragment a well-characterized protein (GB1) as a function of pH and contact time. GB1 was exposed to the soil minerals montmorillonite, goethite, kaolinite, and birnessite at pH 5 and pH 7 for 1, 8, 24, and 168 h and the supernatant was screened for peptide fragments using Tandem Mass Spectrometry. To distinguish between products of oxidative and hydrolytic cleavage, we combined results from the SEQUEST algorithm, which identifies protein fragments that were cleaved hydrolytically, with the output of a deconvolution algorithm (DECON-Routine) designed to identify oxidation fragments. All four minerals were able to induce protein cleavage. Manganese oxide was effective at both hydrolytic and oxidative cleavage. The fact that phyllosilicates-which are not redox active-induced oxidative cleavage indicates that surfaces acted as catalysts and not as reactants. Our results extend previous observations of proteolytic capabilities in soil minerals to the groups of phyllosilicates and Fe-oxides. We identified structural regions of the protein with particularly high susceptibility to cleavage (loops and ß strands) as well as regions that were entirely unaffected (α helix).

Utility of proactive infliximab levels in paediatric Crohn's disease.

OBJECTIVE: Infliximab (IFX) has an established role in Crohn's disease (CD), with serum trough levels of IFX (TLI) increasingly used to optimise dosing. We report the utility of routine, proactive TLI in children on combination therapy with immunosuppression (IS) from a single paediatric centre. METHODS: This is a retrospective chart review of all children with CD receiving IFX therapy conducted betweenJanuary 2014-May 2017. Clinical phenotype, duration of therapy, TLI (µg/mL), drug antibodies, type of IS, biomarkers and changes in management were recorded. RESULTS: 60 children (8-17 years; median 14.1 years) had 206 TLIs recorded. 56/60 (93%) were on IS, with 5/60 (8%) developing antidrug antibodies (ADAs). 63/206 TLIs were recorded duringan episode of relapse (median 3.0 µg/mL) vs 143/206 TLIs recorded in remission (median 5.2 µg/mL). For children with TLI <3 µg/mL, 31/63 (49%) were in relapse vs 30/143 (21%) in remission. For children with TLI >7 µg/mL, 7/63 (11%) were in relapse vs 46/143 (32%) in remission. Change in management resulted from 43/206 (21%) TLIs in 31/60 (52%) children: 21 dose escalations, 12 de-escalations and 10 changed to adalimumab. Of 31 postinduction TLIs, 15/17 (88%) children with TLI >7 µg/mL achieved clinical and biochemical remission for the duration of therapy (median 14 months), while 4/5 (80%) children with TLI <3 µg/mL required early dose escalation. Combination therapy with thiopurines (TP) (median TLI 4.9 µg/mL) versus methotrexate (MTX) (median TLI 5.2 µg/mL) achieved comparable levels with no difference in relapse frequency. CONCLUSIONS: Routine, proactive TLIs guide optimal management in children with CD. Postinduction and during maintenance, levels <3 µg/mL were associated with relapse and levels >7 µg/mL with sustained remission. Combination IS with TP and MTX appears to offer comparable TLI and ADA rates.

High-Yield Methods for Accurate Two-Alternative Visual Psychophysics in Head-Fixed Mice.

Research in neuroscience increasingly relies on the mouse, a mammalian species that affords unparalleled genetic tractability and brain atlases. Here, we introduce high-yield methods for probing mouse visual decisions. Mice are head-fixed, facilitating repeatable visual stimulation, eye tracking, and brain access. They turn a steering wheel to make two alternative choices, forced or unforced. Learning is rapid thanks to intuitive coupling of stimuli to wheel position. The mouse decisions deliver high-quality psychometric curves for detection and discrimination and conform to the predictions of a simple probabilistic observer model. The task is readily paired with two-photon imaging of cortical activity. Optogenetic inactivation reveals that the task requires mice to use their visual cortex. Mice are motivated to perform the task by fluid reward or optogenetic stimulation of dopamine neurons. This stimulation elicits a larger number of trials and faster learning. These methods provide a platform to accurately probe mouse vision and its neural basis.

Integrated Clinical Decision Support Systems Promote Absolute Cardiovascular Risk Assessment: An Important Primary Prevention Measure in Aboriginal and Torres Strait Islander Primary Health Care.

BACKGROUND: Aboriginal and Torres Strait Islander Australians experience a greater burden of disease compared to non-Indigenous Australians. Around one-fifth of the health disparity is caused by cardiovascular disease (CVD). Despite the importance of absolute cardiovascular risk assessment (CVRA) as a screening and early intervention tool, few studies have reported its use within the Australian Indigenous primary health care (PHC) sector. This study utilizes data from a large-scale quality improvement program to examine variation in documented CVRA as a primary prevention strategy for individuals without prior CVD across four Australian jurisdictions. We also examine the proportion with elevated risk and follow-up actions recorded. METHODS: We undertook cross-sectional analysis of 2,052 client records from 97 PHC centers to assess CVRA in Indigenous adults aged ≥20 years with no recorded chronic disease diagnosis (2012-2014). Multilevel regression was used to quantify the variation in CVRA attributable to health center and client level factors. The main outcome measure was the proportion of eligible adults who had CVRA recorded. Secondary outcomes were the proportion of clients with elevated risk that had follow-up actions recorded. RESULTS: Approximately 23% (n = 478) of eligible clients had documented CVRA. Almost all assessments (99%) were conducted in the Northern Territory. Within this jurisdiction, there was wide variation between centers in the proportion of clients with documented CVRA (median 38%; range 0-86%). Regression analysis showed health center factors accounted for 48% of the variation. Centers with integrated clinical decision support systems were more likely to document CVRA (OR 21.1; 95% CI 5.4-82.4; p < 0.001). Eleven percent (n = 53) of clients were found with moderate/high CVD risk, of whom almost one-third were under 35 years (n = 16). Documentation of follow-up varied with respect to the targeted risk factor. Fewer than 30% with abnormal blood lipid or glucose levels had follow-up management plans recorded. CONCLUSION: There was wide variation in CVRA between jurisdictions and between PHC centers. Learnings from successful interventions to educate and support centers in CVRA provision should be shared with stakeholders more widely. Where risk has been identified, further improvement in follow-up management is required to prevent CVD onset and reduce future burden in Australia's Indigenous population.

Improving preventive health care in Aboriginal and Torres Strait Islander primary care settings.

BACKGROUND: Like other colonised populations, Indigenous Australians experience poorer health outcomes than non-Indigenous Australians. Preventable chronic disease is the largest contributor to the health differential between Indigenous and non-Indigenous Australians, but recommended best-practice preventive care is not consistently provided to Indigenous Australians. Significant improvement in health care delivery could be achieved through identifying and minimising evidence-practice gaps. Our objective was to use clinical audit data to create a framework of the priority evidence-practice gaps, strategies to address them, and drivers to support these strategies in the delivery of recommended preventive care. METHODS: De-identified preventive health clinical audit data from 137 primary health care (PHC) centres in five jurisdictions were analysed (n = 17,108 audited records of well adults with no documented major chronic disease; 367 system assessments; 2005-2014), together with stakeholder survey data relating to interpretation of these data, using a mixed-methods approach (n = 152 responses collated in 2015-16). Stakeholders surveyed included clinicians, managers, policy officers, continuous quality improvement (CQI) facilitators and academics. Priority evidence-practice gaps and associated barriers, enablers and strategies to address the gaps were identified and reported back through two-stages of consultation. Further analysis and interpretation of these data were used to develop a framework of strategies and drivers for health service improvement. RESULTS: Stakeholder identified priorities were: following-up abnormal test results; completing cardiovascular risk assessments; timely recording of results; recording enquiries about living conditions, family relationships and substance use; providing support for clients identified with emotional wellbeing risk; enhancing systems to enable team function and continuity of care. Drivers identified for improving care in these areas included: strong Indigenous participation in the PHC service; appropriate team structure and function to support preventive care; meaningful use of data to support quality of care and CQI; and corporate support functions and structures. CONCLUSION: The framework should be useful for guiding development and implementation of barrier-driven, tailored interventions for primary health care service delivery and policy contexts, and for guiding further research. While specific strategies to improve the quality of preventive care need to be tailored to local context, these findings reinforce the requirement for multi-level action across the system. The framework and findings may be useful for similar purposes in other parts of the world, with appropriate attention to context in different locations.

Comparing swallowing of capsule to endoscopic placement of capsule endoscopy in children.

BACKGROUND AND AIM: Capsule endoscopy (CE) offers a method of directly visualizing areas of the small bowel not accessible by conventional endoscopy. Some children are unable to swallow the capsule requiring endoscopic placement under general anesthesia. The aim of the present study was to identify any differences between children requiring endoscopic placement and those able to swallow the capsule. METHODS: Retrospective chart review of consecutive CE in a tertiary pediatric center was conducted. Patient demographics, outcomes, and complications between the two groups were noted. Paired t-test comparing continuous variables and Fisher exact test for categorical data were used. RESULTS: A total of 104 CEs were performed in 88 patients, median age 12.8 (range: 1.6-18.5) years. Almost half, 49% (51/104), swallowed the capsule. Children requiring endoscopic placement were significantly younger (9.8 vs 14.2 years; P < 0.001), lighter (34.5 vs 54.9 kg; P < 0.0001), and had longer small intestinal transit time (308 vs 229 min; P < 0.0001). Positive findings were more likely in those who swallowed the capsule (50% vs 30%, P = 0.017), likely a reflection of the indications for procedure. Poor views were found in 30% (16/53) of patients in the endoscopic placement group due to iatrogenic bleeding from biopsies taken from concurrent procedures but did not affect outcome or subsequent patient management. CONCLUSIONS: CE is safe and well tolerated in children. Children requiring endoscopic placement were significantly younger, lighter, had longer small intestine transit time, and less likely to have positive findings. Concurrent biopsies during capsule placement increase the likelihood of inadequate views but did not affect outcome or management.

Wide Variation in Absolute Cardiovascular Risk Assessment in Aboriginal and Torres Strait Islander People with Type 2 Diabetes.

BACKGROUND: Absolute cardiovascular risk assessment (CVRA) is based on the combined effects of multiple risk factors and can identify asymptomatic individuals at high risk of cardiovascular disease (CVD). Aboriginal and Torres Strait Islander people, the Indigenous people of Australia, are disproportionately affected by CVD and diabetes. Our study aimed to investigate variations in the use of absolute CVRA in patients with diabetes at Indigenous community healthcare centers and to identify patient and health center characteristics that may contribute to this variation. METHODS: Audits of clinical records of 1,728 patients with a known diagnosis of diabetes across 121 health centers in four Australian States/Territories [Northern Territory (NT), South Australia, Western Australia, and Queensland] over the period 2012-2014 were conducted as part of a large-scale continuous quality improvement program. Multilevel regression modeling was used to quantify variation in recording of CVRA attributable to health center and patient characteristics. RESULTS: The proportion of eligible patients with documented CVRA was 33% (n = 574/1,728). The majority (95%) of assessments were conducted in the NT. Multilevel regression analysis showed health center characteristics accounted for 70% of the variation in assessments in the NT. Government-operated health centers had 18.8 times the odds (95% CI 7.7-46.2) of recording CVRA delivery compared with other health centers. CONCLUSION: Health centers in the NT delivered the majority of absolute CVRA to Indigenous patients with diabetes in our study. Health systems factors that may have facilitated provision of CVRA in the NT include decision support tools and a reporting process for CVRA delivery. Implementation of similar systems in other jurisdictions may help improve CVRA delivery. Early identification and treatment of high risk individuals through wider use of CVRA may help reduce the burden of CVD in Indigenous Australians with diabetes.

Immune cell subsets and their gene expression profiles from human PBMC isolated by Vacutainer Cell Preparation Tube (CPT™) and standard density gradient.

BACKGROUND: High quality genetic material is an essential pre-requisite when analyzing gene expression using microarray technology. Peripheral blood mononuclear cells (PBMC) are frequently used for genomic analyses, but several factors can affect the integrity of nucleic acids prior to their extraction, including the methods of PBMC collection and isolation. Due to the lack of the relevant data published, we compared the Ficoll-Paque density gradient centrifugation and BD Vacutainer cell preparation tube (CPT) protocols to determine if either method offered a distinct advantage in preparation of PBMC-derived immune cell subsets for their use in gene expression analysis. We evaluated the yield and purity of immune cell subpopulations isolated from PBMC derived by both methods, the quantity and quality of extracted nucleic acids, and compared gene expression in PBMC and individual immune cell types from Ficoll and CPT isolation protocols using Affymetrix microarrays. RESULTS: The mean yield and viability of fresh PBMC acquired by the CPT method (1.16 × 10(6) cells/ml, 93.3%) were compatible to those obtained with Ficoll (1.34 × 10(6) cells/ml, 97.2%). No differences in the mean purity, recovery, and viability of CD19+ (B cells), CD8+ (cytotoxic T cells), CD4+ (helper T cell) and CD14+ (monocytes) positively selected from CPT- or Ficoll-isolated PBMC were found. Similar quantities of high quality RNA and DNA were extracted from PBMC and immune cells obtained by both methods. Finally, the PBMC isolation methods tested did not impact subsequent recovery and purity of individual immune cell subsets and, importantly, their gene expression profiles. CONCLUSIONS: Our findings demonstrate that the CPT and Ficoll PBMC isolation protocols do not differ in their ability to purify high quality immune cell subpopulations. Since there was no difference in the gene expression profiles between immune cells obtained by these two methods, the Ficoll isolation can be substituted by the CPT protocol without conceding phenotypic changes of immune cells and compromising the gene expression studies. Given that the CPT protocol is less elaborate, minimizes cells' handling and processing time, this method offers a significant operating advantage, especially in large-scale clinical studies aiming at dissecting gene expression in PBMC and PBMC-derived immune cell subpopulations.