Evaluation of various membranes at different fluxes to enable large-volume single-use perfusion bioreactors.

The growing demand for biological therapeutics has increased interest in large-volume perfusion bioreactors, but the operation and scalability of perfusion membranes remain a challenge. This study evaluates perfusion cell culture performance and monoclonal antibody (mAb) productivity at various membrane fluxes (1.5-5 LMH), utilizing polyvinylidene difluoride (PVDF), polyethersulfone (PES), or polysulfone (PS) membranes in tangential flow filtration mode. At low flux, culture with PVDF membrane maintained higher cell culture growth, permeate titer (1.06-1.34 g/L) and sieving coefficients (≥83%) but showed lower permeate volumetric throughput and higher transmembrane pressure (TMP) (>1.50 psi) in the later part of the run compared to cultures with PES and PS membrane. However, as permeate flux increased, the total mass of product decreased by around 30% for cultures with PVDF membrane, while it remained consistent with PES and PS membrane, and at the highest flux studied, PES membrane generated 12% more product than PVDF membrane. This highlights that membrane selection for large-volume perfusion bioreactors depends on the productivity and permeate flux required. Since operating large-volume perfusion bioreactors at low flux would require several cell retention devices and a complex setup, PVDF membranes are suitable for low-volume operations at low fluxes whereas PES membranes can be a desirable alternative for large-volume higher demand products at higher fluxes.

Contributions of Chinese hamster ovary cell derived extracellular vesicles and other cellular materials to hollow fiber filter fouling during perfusion manufacturing of monoclonal antibodies.

Hollow fiber filter fouling is a common issue plaguing perfusion production process for biologics therapeutics, but the nature of filter foulant has been elusive. Here we studied cell culture materials especially Chinese hamster ovary (CHO) cell-derived extracellular vesicles in perfusion process to determine their role in filter fouling. We found that the decrease of CHO-derived small extracellular vesicles (sEVs) with 50-200 nm in diameter in perfusion permeates always preceded the increase in transmembrane pressure (TMP) and subsequent decrease in product sieving, suggesting that sEVs might have been retained inside filters and contributed to filter fouling. Using scanning electron microscopy and helium ion microscopy, we found sEV-like structures in pores and on foulant patches of hollow fiber tangential flow filtration filter (HF-TFF) membranes. We also observed that the Day 28 TMP of perfusion culture correlated positively with the percentage of foulant patch areas. In addition, energy dispersive X-ray spectroscopy-based elemental mapping microscopy and spectroscopy analysis suggests that foulant patches had enriched cellular materials but not antifoam. Fluorescent staining results further indicate that these cellular materials could be DNA, proteins, and even adherent CHO cells. Lastly, in a small-scale HF-TFF model, addition of CHO-specific sEVs in CHO culture simulated filter fouling behaviors in a concentration-dependent manner. Based on these results, we proposed a mechanism of HF-TFF fouling, in which filter pore constriction by CHO sEVs is followed by cake formation of cellular materials on filter membrane.

Role of Hydroperoxyl Radicals in Heterogeneous Oxidation of Oxygenated Organic Aerosols.

Heterogeneous oxidative aging of organic aerosols (OA) occurs ubiquitously in the atmosphere, initiated by oxidants, such as the hydroxyl radicals (•OH). Hydroperoxyl radicals (HO2•) are also an important oxidant in the troposphere, and its gas-phase chemistry has been well studied. However, the role of HO2• in heterogeneous OA oxidation remains elusive. Here, we carry out •OH-initiated heterogeneous oxidation of several OA model systems under different HO2• conditions in a flow tube reactor and characterize the molecular oxidation products using a suite of mass spectrometry instrumentation. By using hydrogen-deuterium exchange (HDX) with thermal desorption iodide-adduct chemical ionization mass spectrometry, we provide direct observation of organic hydroperoxide (ROOH) formation from heterogeneous HO2• and peroxy radicals (RO2•) reactions for the first time. The ROOH may contribute substantially to the oxidation products, varied with the parent OA chemical structure. Furthermore, by regulating RO2• reaction pathways, HO2• also greatly influence the overall composition of the oxidized OA. Last, we suggest that the RO2• + HO2• reactions readily occur at the OA particle interface rather than in the particle bulk. These findings provide new mechanistic insights into the heterogeneous OA oxidation chemistry and help fill the critical knowledge gap in understanding atmospheric OA oxidative aging.

Compliance of healthcare workers in a psychiatric inpatient ward to infection control practices during the COVID-19 pandemic: a participant observation study supplemented with a self-reported survey.

BACKGROUND: As an emerging infectious disease with a heterogenous and uncertain transmission pattern, coronavirus disease 2019 (COVID-19) has created a catastrophe in healthcare-associated infections (HAIs) and posed a significant challenge to infection control practices (ICPs) in healthcare settings. While the unique characteristics of psychiatric patients and clinical settings may make the implementation of ICPs difficult, evidence is lacking for compliance with ICPs among healthcare workers (HCWs) in a psychiatric setting during the COVID-19 pandemic. METHODS: A cross-sectional multi-method study based on participant unobtrusive observation coupled with the completion of a self-administered ICP survey was conducted to assess compliance with ICPs among HCWs in a psychiatric inpatient ward in a regional hospital. An online checklist, called eRub, was used to record the performance of HCWs in hand hygiene (HH) and other essential ICPs. Furthermore, a well-validated questionnaire (i.e., Compliance with Standard Precautions Scale, CSPS) was used to collect the participants' self-reported ICP compliance for later comparison. RESULTS: A total of 2,670 ICP opportunities were observed from January to April 2020. The overall compliance rate was 42.6%. HCWs exhibited satisfactory compliance to the wearing of mask (91.2%) and the handling of clinical waste (87.5%); suboptimal compliance to the handling of sharp objects (67.7%) and linen (72.7%); and poor compliance to HH (3.3%), use of gloves (40.9%), use of personal protective equipment (20%), and disinfection of used surface/area (0.4%). The compliance rates of the nurses and support staff to HH were significantly different (χ2 = 123.25, p < 0.001). In the self-reported survey, the overall compliance rate for ICPs was 64.6%. CONCLUSION: The compliance of HCWs in a psychiatric inpatient ward to ICPs during the COVID-19 pandemic ranged from poor to suboptimal. This result was alarming. Revisions of current ICP guidelines and policies that specifically target barriers in psychiatric settings will be necessary.

Proton pump inhibitors, antibiotics, and atopy increase the risk of eosinophilic esophagitis in children with esophageal atresia.

OBJECTIVE: To determine whether proton pump inhibitor (PPI) exposure is associated with an increased risk of developing eosinophilic esophagitis (EoE) in children with esophageal atresia (EA). STUDY DESIGN: A retrospective chart review of children with EA from January 1, 2005 to December 31, 2020 was undertaken at Sydney Children's Hospital Randwick. Children with EA and EoE (cases) were matched (1:2) to children with only EA (controls) to compare PPI exposure. Other early-life factors such as infantile antibiotic exposure and personal or family history of atopy were also analyzed using simple and multivariable logistic regression. RESULTS: Of 184 children with EA, 46 (25%) developed EoE during this period. Thirty-eight EoE participants were matched to 76 controls. Children with EoE and EA received PPI for significantly higher durations (p = .018) and at significantly higher cumulative doses (p = .017) than controls. Food allergy (adjusted odds ratio [aOR], 7.317; 95% confidence interval [CI], 2.244-23.742), family history of atopy (aOR, 3.504; 95% CI, 1.268-9.682), and infantile antibiotic exposure (aOR, 1.040; 95% CI, 1.006-1.075) were also significantly associated with an increased risk of developing EoE in the EA cohort. CONCLUSIONS: Prolonged duration and high cumulative dose of PPI exposure were significantly associated with subsequent EoE development in children with EA. Food allergy, family history of atopy, and infantile antibiotic exposure in EA were also significantly associated with an increased risk of EoE development.

Can repeated intranasal oxytocin administration affect reduced neural sensitivity towards expressive faces in autism? A randomized controlled trial.

BACKGROUND: Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by difficulties in social communication and interaction. Crucial for efficient social interaction is the ability to quickly and accurately extract information from a person's face. Frequency-tagging electroencephalography (EEG) is a novel tool to quantify face-processing sensitivity in a robust and implicit manner. In terms of intervention approaches, intranasal administration of oxytocin (OT) is increasingly considered as a potential pharmacological approach for improving socio-communicative difficulties in ASD, through enhancing social salience and/or reducing (social) stress and anxiety. METHODS: In this randomized, double-blind, placebo-controlled, mechanistic pharmaco-neuroimaging clinical trial, we implemented frequency-tagging EEG to conduct an exploratory investigation into the impact of repeated OT administration (4 weeks, 12 IU, twice daily) on neural sensitivity towards happy and fearful facial expressions in children with ASD (8-12 years old; OT: n = 29; placebo: n = 32). Neural effects were assessed at baseline, post-nasal spray (24 hr after the last nasal spray) and at a follow-up session, 4 weeks after the OT administration period. At baseline, neural assessments of children with ASD were compared with those of an age- and gender-matched cohort of neurotypical (NT) children (n = 39). RESULTS: Children with ASD demonstrated reduced neural sensitivity towards expressive faces, as compared to NT children. Upon nasal spray administration, children with ASD displayed a significant increase in neural sensitivity at the post- and follow-up sessions, but only in the placebo group, likely reflecting an implicit learning effect. Strikingly, in the OT group, neural sensitivity remained unaffected from the baseline to the post-session, likely reflecting a dampening of an otherwise typically occurring implicit learning effect. CONCLUSIONS: First, we validated the robustness of the frequency-tagging EEG approach to assess reduced neural sensitivity towards expressive faces in children with ASD. Furthermore, in contrast to social salience effects observed after single-dose administrations, repeated OT administration dampened typically occurring learning effects in neural sensitivity. In line with OT's social anxiolytic account, these observations possibly reflect a predominant (social) stress regulatory effect towards emotionally evocative faces after repeated OT administration.

At the Head and Heart of Oxytocin's Stress-Regulatory Neural and Cardiac Effects: A Chronic Administration RCT in Children with Autism.

INTRODUCTION: Intranasal administration of oxytocin presents a promising new approach to reduce disability associated with an autism spectrum disorder diagnosis. Previous investigations have emphasized the amygdala as the neural foundation for oxytocin's acute effects. However, to fully understand oxytocin's therapeutic potential, it is crucial to gain insight into the neuroplastic changes in amygdala circuitry induced from chronic oxytocin administrations, particularly in pediatric populations. OBJECTIVE: We aimed to examine the impact of a 4-week course of intranasal oxytocin on amygdala functional connectivity in children with autism, compared to placebo. Additionally, we investigated whether oxytocin improves cardiac autonomic arousal, as indexed by high-frequency heart rate variability. METHODS: Fifty-seven children with autism aged 8-12 years (45 boys, 12 girls) participated in a double-blind, randomized pharmaco-neuroimaging trial involving twice-daily administrations of intranasal oxytocin or placebo. Resting-state fMRI scans and simultaneous, in-scanner heart rate recordings were obtained before, immediately after, and 4 weeks after the nasal spray administration period. RESULTS: Significant reductions in intrinsic amygdala-orbitofrontal connectivity were observed, particularly at the 4-week follow-up session. These reductions were correlated with improved social symptoms and lower cardiac autonomic arousal. Further, oxytocin's neural and cardiac autonomic effects were modulated by epigenetic modifications of the oxytocin receptor gene. The effects were more pronounced in children with reduced epigenetic methylation, signifying heightened expression of the oxytocin receptor. CONCLUSION: These findings underscore that a 4-week oxytocin administration course decreases amygdala connectivity and improves cardiac autonomic balance. Epigenetic modulators may explain inter-individual variation in responses to oxytocin.

Oxidation of Per- and Polyfluoroalkyl Ether Acids and Other Per- and Polyfluoroalkyl Substances by Sulfate and Hydroxyl Radicals: Kinetic Insights from Experiments and Models.

Per- and polyfluoroalkyl substances (PFAS) are widely used anthropogenic chemicals. Because of the strength of the carbon-fluorine bond, PFAS are not destroyed in typical water treatment processes. Sulfate (SO4•-) and hydroxyl (•OH) radicals can oxidize some PFAS, but the behavior of per- and polyfluoroalkyl ether acids (PFEAs) in processes involving SO4•- and •OH is poorly understood. In this study, we determined second-order rate constants (k) describing the oxidation of 18 PFAS, including 15 novel PFEAs, by SO4•- and •OH. Among the studied PFAS, 6:2 fluorotelomer sulfonate reacted most readily with •OH [k•OH = (1.1-1.2) × 107 M-1 s-1], while polyfluoroalkyl ether acids containing an -O-CFH- moiety reacted more slowly [k•OH = (0.5-1.0) × 106 M-1 s-1]. In the presence of SO4•-, polyfluoroalkyl ether acids with an -O-CFH- moiety reacted more rapidly [kSO4•- = (0.89-4.6) × 106 M-1 s-1] than perfluoroalkyl ether carboxylic acids (PFECAs) and a chloro-perfluoro-polyether carboxylic acid (ClPFPECA) [kSO4•- = (0.85-9.5) × 104 M-1 s-1]. For homologous series of perfluoroalkyl carboxylic acids, linear and branched monoether PFECAs, and multiether PFECAs, PFAS chain length had little impact on second-order rate constants. SO4•- reacted with the carboxylic acid headgroup of perfluoroalkyl carboxylic acids and PFECAs. In contrast, for polyfluoroalkyl ether carboxylic and sulfonic acids with an -O-CFH- moiety, the site of SO4•- attack was the -O-CFH- moiety. Perfluoroalkyl ether sulfonic acids were not oxidized by SO4•- and •OH under the conditions evaluated in this study.

A genomic-augmented multivariate prognostic model for the survival of natural-killer/T-cell lymphoma patients from an international cohort.

With lowering costs of sequencing and genetic profiling techniques, genetic drivers can now be detected readily in tumors but current prognostic models for Natural-killer/T cell lymphoma (NKTCL) have yet to fully leverage on them for prognosticating patients. Here, we used next-generation sequencing to sequence 260 NKTCL tumors, and trained a genomic prognostic model (GPM) with the genomic mutations and survival data from this retrospective cohort of patients using LASSO Cox regression. The GPM is defined by the mutational status of 13 prognostic genes and is weakly correlated with the risk-features in International Prognostic Index (IPI), Prognostic Index for Natural-Killer cell lymphoma (PINK), and PINK-Epstein-Barr virus (PINK-E). Cox-proportional hazard multivariate regression also showed that the new GPM is independent and significant for both progression-free survival (PFS, HR: 3.73, 95% CI 2.07-6.73; p < .001) and overall survival (OS, HR: 5.23, 95% CI 2.57-10.65; p = .001) with known risk-features of these indices. When we assign an additional risk-score to samples, which are mutant for the GPM, the Harrell's C-indices of GPM-augmented IPI, PINK, and PINK-E improved significantly (p < .001, χ2 test) for both PFS and OS. Thus, we report on how genomic mutational information could steer toward better prognostication of NKTCL patients.

Ca2+ Ions Promote Fusion of Middle East Respiratory Syndrome Coronavirus with Host Cells and Increase Infectivity.

Fusion with, and subsequent entry into, the host cell is one of the critical steps in the life cycle of enveloped viruses. For Middle East respiratory syndrome coronavirus (MERS-CoV), the spike (S) protein is the main determinant of viral entry. Proteolytic cleavage of the S protein exposes its fusion peptide (FP), which initiates the process of membrane fusion. Previous studies on the related severe acute respiratory syndrome coronavirus (SARS-CoV) FP have shown that calcium ions (Ca2+) play an important role in fusogenic activity via a Ca2+ binding pocket with conserved glutamic acid (E) and aspartic acid (D) residues. SARS-CoV and MERS-CoV FPs share a high sequence homology, and here, we investigated whether Ca2+ is required for MERS-CoV fusion by screening a mutant array in which E and D residues in the MERS-CoV FP were substituted with neutrally charged alanines (A). Upon verifying mutant cell surface expression and proteolytic cleavage, we tested their ability to mediate pseudoparticle (PP) infection of host cells in modulating Ca2+ environments. Our results demonstrate that intracellular Ca2+ enhances MERS-CoV wild-type (WT) PP infection by approximately 2-fold and that E891 is a crucial residue for Ca2+ interaction. Subsequent electron spin resonance (ESR) experiments revealed that this enhancement could be attributed to Ca2+ increasing MERS-CoV FP fusion-relevant membrane ordering. Intriguingly, isothermal calorimetry showed an approximate 1:1 MERS-CoV FP to Ca2+ ratio, as opposed to an 1:2 SARS-CoV FP to Ca2+ ratio, suggesting significant differences in FP Ca2+ interactions of MERS-CoV and SARS-CoV FP despite their high sequence similarity.IMPORTANCE Middle East respiratory syndrome coronavirus (MERS-CoV) is a major emerging infectious disease with zoonotic potential and has reservoirs in dromedary camels and bats. Since its first outbreak in 2012, the virus has repeatedly transmitted from camels to humans, with 2,468 confirmed cases causing 851 deaths. To date, there are no efficacious drugs and vaccines against MERS-CoV, increasing its potential to cause a public health emergency. In order to develop novel drugs and vaccines, it is important to understand the molecular mechanisms that enable the virus to infect host cells. Our data have found that calcium is an important regulator of viral fusion by interacting with negatively charged residues in the MERS-CoV FP region. This information can guide therapeutic solutions to block this calcium interaction and also repurpose already approved drugs for this use for a fast response to MERS-CoV outbreaks.

Single B-Cell Genomic Analyses Differentiate Vitreoretinal Lymphoma from Chronic Inflammation.

PURPOSE: To test whether analyzing DEPArray (Menarini Silicon Biosystems) isolated single B cells from the vitreous fluid can reveal crucial genomic and clinicopathological features to distinguish patients with vitreoretinal lymphoma (VRL) from those with chronic inflammation using immunoglobulin heavy chain (IGH), disease biomarker myeloid differentiation primary response 88 (MYD88)L265P mutation, and copy number profiling. DESIGN: A single-center, retrospective study. PARTICIPANTS: Remnant vitreous biopsies from 7 patients with VRL and 4 patients with chronic inflammation were acquired for molecular analysis. METHODS: Vitreous fluid samples were prefixed in PreservCyt (Hologic) and underwent cytologic analysis and immunohistochemistry examination. Single cells were isolated using the DEPArray NxT system, followed by downstream genomic analysis. MAIN OUTCOME MEASURES: The frequencies of the dominant IGH and MYD88L265P mutation and the genome-wide copy number aberration (CNA) profiles of individual vitreous-isolated B cells were characterized. RESULTS: An average of 10 to 13 vitreous B cells were used in the single-cell IGH and MYD88 analyses. Higher frequencies of dominant IGH (88.8% ± 13.2%) and MYD88L265P mutations (35.0% ± 31.3%) were detected in patients with VRL than in patients with chronic inflammation (65.9% ± 13.4% and 1.5% ± 2.6% for IGH and MYD88L265P, respectively). In a cytology-proven VRL case, all 15 vitreous isolated B cells were derived from the same clone with 100% paired IGH: immunoglobulin light chain (IGK) sequences. Genome-wide copy number profiling revealed a high degree of similarity between B cells from the same patient with VRL, with extensive gains and losses at the same areas across the whole genome. In addition, 14 of 15 B cells showed a BCL2/JH t(14;18) translocation, confirming cellular malignancy with a clonal origin. Clustering analysis of the copy number profiles revealed that malignant B cells derived from different patients with VRL had no common genome-wide signatures. CONCLUSIONS: Single B-cell genomic characterization of the IGH, MYD88L265P mutation, and copy number profile enables VRL diagnosis. Because our study involved only a small cohort, these meaningful proof-of-concept data now warrant further investigation in a larger patient cohort.

Phase I study of selinexor in combination with dexamethasone, ifosfamide, carboplatin, etoposide chemotherapy in patients with relapsed or refractory peripheral T-cell or natural-killer/T-cell lymphoma

Selinexor is a selective inhibitor of nuclear export with anti-cancer properties. We performed a phase I study to determine the safety and maximum tolerated dose (MTD) of selinexor when combined with high-dose dexamethasone, ifosfamide, carboplatin and etoposide (DICE) in relapsed/refractory (R/R) T-cell lymphoma (TCL) and natural-killer/T-cell lymphoma (NKTL). Patients with R/R TCL and NKTL were treated with standard dose ICE, dexamethasone 20mg on days 3 to 7, and escalating doses of oral selinexor on days 3, 5 and 7 in a 3+3 design. Dose level (DL) 1, 2 and 3 were 40, 60 and 80mg respectively. Eleven patients with a median age of 60 were enrolled; 6 at DL1 and 5 at DL2. Patients had received a median of 2 (range 1-4) prior lines of treatment and 7 had primary refractory disease at study entry. Patients received a median of 3 cycles (range 1-6) of selinexor-DICE. The most common grade (G) 1/2 toxicities included nausea (64%), fatigue (55%), and anorexia (45%) and the most common G 3/4 toxicities included thrombocytopenia (82%), anemia (82%), neutropenia (73%), and hyponatremia (73%). Two patients developed doselimiting toxicities at DL2 and one at DL1. Five patients discontinued treatment for reasons other than disease progression or lack of response. Of the 10 evaluable patients, the overall and complete response rates were 91% and 82% respectively. The MTD of selinexor was 40mg when combined with DICE. The combination showed promising CR rates in patients with R/R TCL and NKTL but was poorly tolerated.

Treatment patterns and outcomes of older patients with mantle cell lymphoma in an Asian population.

BACKGROUND: Significant progress has been made in the treatment outcomes of mantle cell lymphoma (MCL) since the introduction of cytarabine and rituximab in modern regimens. However, older patients may not readily tolerate these agents nor derive benefit. We investigated the impact of age on treatment patterns and clinical outcomes of MCL patients in an Asian population. METHODS: A retrospective study was conducted on patients (n = 66) diagnosed with MCL at the National Cancer Centre Singapore between 1998 and 2018. The median follow-up duration was 40 months. Survival analyses were performed using the Kaplan-Meier method and multivariate Cox proportional models. RESULTS: The median age of the cohort was 59 years (range, 26-84), with a male predominance (73%). The majority (86%) had advanced stage 3-4 disease at diagnosis. Compared with younger patients, older patients aged ≥60 years (n = 32; 48.5%) presented more frequently with B-symptoms (75% vs 38%, p = 0.0028), anaemia (75% vs 35%, p = 0.0013), and carried higher prognostic risk scores (sMIPI high risk 84% vs 56%, p = 0.016). Non-cytarabine-based induction chemotherapy was more commonly administered in older patients (76% vs 32%, p = 0.0012). The 5-year overall survival (OS) and progression-free survival (PFS) was 68 and 25% respectively. In a multivariable model, older age (HR 3.42, 95%CI 1.48-7.92, p = 0.004) and anemia (HR 2.56, 95%CI 1.10-5.96, p = 0.029) were independently associated with poorer OS while older age (HR 2.24, 95%CI 1.21-4.14, p = 0.010) and hypoalbuminemia (HR 2.20, 95%CI 1.17-4.13, p = 0.014) were independently associated with poorer PFS. In an exploratory analysis, maintenance rituximab following induction chemotherapy improved PFS in younger patients, with median PFS of 131 months and 45 months with or without maintenance therapy respectively (HR 0.39, 95%CI 0.16-0.93, p = 0.035). In contrast, no survival benefit was observed in older patients. CONCLUSIONS: We demonstrated in our analysis that older patients with MCL may harbor adverse clinical features and may not derive benefit from maintenance rituximab, highlighting the need for further research in this area of need.

Genetic risk of extranodal natural killer T-cell lymphoma: a genome-wide association study in multiple populations.

BACKGROUND: Extranodal natural killer T-cell lymphoma (NKTCL; nasal type) is an aggressive malignancy with a particularly high prevalence in Asian and Latin American populations. Epstein-Barr virus infection has a role in the pathogenesis of NKTCL, and HLA-DPB1 variants are risk factors for the disease. We aimed to identify additional novel genetic variants affecting risk of NKTCL. METHODS: We did a genome-wide association study of NKTCL in multiple populations from east Asia. We recruited a discovery cohort of 700 cases with NKTCL and 7752 controls without NKTCL of Han Chinese ancestry from 19 centres in southern, central, and northern regions of China, and four independent replication samples including 717 cases and 12 650 controls. Three of these independent samples (451 cases and 5301 controls) were from eight centres in the same regions of southern, central, and northern China, and the fourth (266 cases and 7349 controls) was from 11 centres in Hong Kong, Taiwan, Singapore, and South Korea. All cases had primary NKTCL that was confirmed histopathologically, and matching with controls was based on geographical region and self-reported ancestry. Logistic regression analysis was done independently by geographical regions, followed by fixed-effect meta-analyses, to identify susceptibility loci. Bioinformatic approaches, including expression quantitative trait loci, binding motif and transcriptome analyses, and biological experiments were done to fine-map and explore the functional relevance of genome-wide association loci to the development of NKTCL. FINDINGS: Genetic data were gathered between Jan 1, 2008, and Jan 23, 2019. Meta-analysis of all samples (a total of 1417 cases and 20 402 controls) identified two novel loci significantly associated with NKTCL: IL18RAP on 2q12.1 (rs13015714; p=2·83 × 10-16; odds ratio 1·39 [95% CI 1·28-1·50]) and HLA-DRB1 on 6p21.3 (rs9271588; 9·35 × 10-26 1·53 [1·41-1·65]). Fine-mapping and experimental analyses showed that rs1420106 at the promoter of IL18RAP was highly correlated with rs13015714, and the rs1420106-A risk variant had an upregulatory effect on IL18RAP expression. Cell growth assays in two NKTCL cell lines (YT and SNK-6 cells) showed that knockdown of IL18RAP inhibited cell proliferation by cell cycle arrest in NKTCL cells. Haplotype association analysis showed that haplotype 47F-67I was associated with reduced risk of NKTCL, whereas 47Y-67L was associated with increased risk of NKTCL. These two positions are component parts of the peptide-binding pocket 7 (P7) of the HLA-DR heterodimer, suggesting that these alterations might account for the association at HLA-DRB1, independent of the previously reported HLA-DPB1 variants. INTERPRETATION: Our findings provide new insights into the development of NKTCL by showing the importance of inflammation and immune regulation through the IL18-IL18RAP axis and antigen presentation involving HLA-DRB1, which might help to identify potential therapeutic targets. Taken in combination with additional genetic and other risk factors, our results could potentially be used to stratify people at high risk of NKTCL for targeted prevention. FUNDING: Guangdong Innovative and Entrepreneurial Research Team Program, National Natural Science Foundation of China, National Program for Support of Top-Notch Young Professionals, Chang Jiang Scholars Program, Singapore Ministry of Health's National Medical Research Council, Tanoto Foundation, National Research Foundation Singapore, Chang Gung Memorial Hospital, Recruitment Program for Young Professionals of China, First Affiliated Hospital and Army Medical University, US National Institutes of Health, and US National Cancer Institute.

Pinpointing the optimal spatial frequency range for automatic neural facial fear processing.

Faces convey an assortment of emotional information via low and high spatial frequencies (LSFs and HSFs). However, there is no consensus on the role of particular spatial frequency (SF) information during facial fear processing. Comparison across studies is hampered by the high variability in cut-off values for demarcating the SF spectrum and by differences in task demands. We investigated which SF information is minimally required to rapidly detect briefly presented fearful faces in an implicit and automatic manner, by sweeping through an entire SF range without constraints of predefined cut-offs for LSFs and HSFs. We combined fast periodic visual stimulation with electroencephalography. We presented neutral faces at 6 â€‹Hz, periodically interleaved every 5th image with a fearful face, allowing us to quantify an objective neural index of fear discrimination at exactly 1.2 â€‹Hz. We started from a stimulus containing either only very low or very high SFs and gradually increased the SF content by adding higher or lower SF information, respectively, to reach the full SF spectrum over the course of 70 â€‹s. We found that faces require at least SF information higher than 5.93 cycles per image (cpi) to implicitly differentiate fearful from neutral faces. However, exclusive HSF faces, even in a restricted SF range between 94.82 and 189.63 cpi already carry the critical information to extract the emotional expression of the faces.

Evaluation of the PIK3 pathway in peripheral T-cell lymphoma and NK/T-cell lymphoma.

Peripheral T-cell lymphomas (PTCL) and natural killer (NK)/T-cell lymphomas (NKTCL) are a heterogeneous group of aggressive malignancies with dismal outcomes and limited treatment options. While the phosphatidylinositol 3-kinase (PIK3) pathway has been shown to be highly activated in many B-cell lymphomas, its therapeutic relevance in PTCL and NKTCL remains unclear. The aim of this study is to investigate the expression of PIK3 and phosphatase and tensin homolog (PTEN) in these subtypes of lymphoma and to identify potential therapeutic targets for clinical testing. Therefore, the expression of PIK3α, PIK3ß, PIK3γ, PIK3δ and PTEN was analyzed in 88 cases of PTCL and NKTCL samples by immunohistochemistry. All PTCL and NKTCL samples demonstrated high expression of PIK3 isoforms. In particular, high PIK3α expression was significantly associated with poor survival, even after adjustment for age, International Prognostic Index (IPI) score and anthracycline-based chemotherapy in first line. Notably, copanlisib, a pan-class I inhibitor with predominant activities towards PIK3α and PIK3δ isoforms, effectively inhibited phosphorylation of AKT, 4E-BP-1 and STAT3, causing G0 /G1 cell cycle arrest and resulting in suppression of tumour cell growth in vitro and in vivo. This study provides evidence that targeting the PIK3 pathway, particularly simultaneous inhibition of PIK3α and δ, could be a promising approach for the treatment of PTCL and NKTCL.

Oncogenic activation of the STAT3 pathway drives PD-L1 expression in natural killer/T-cell lymphoma.

Mature T-cell lymphomas, including peripheral T-cell lymphoma (PTCL) and extranodal NK/T-cell lymphoma (NKTL), represent a heterogeneous group of non-Hodgkin lymphomas with dismal outcomes and limited treatment options. To determine the extent of involvement of the JAK/STAT pathway in this malignancy, we performed targeted capture sequencing of 188 genes in this pathway in 171 PTCL and NKTL cases. A total of 272 nonsynonymous somatic mutations in 101 genes were identified in 73% of the samples, including 258 single-nucleotide variants and 14 insertions or deletions. Recurrent mutations were most frequently located in STAT3 and TP53 (15%), followed by JAK3 and JAK1 (6%) and SOCS1 (4%). A high prevalence of STAT3 mutation (21%) was observed specifically in NKTL. Novel STAT3 mutations (p.D427H, E616G, p.E616K, and p.E696K) were shown to increase STAT3 phosphorylation and transcriptional activity of STAT3 in the absence of cytokine, in which p.E616K induced programmed cell death-ligand 1 (PD-L1) expression by robust binding of activated STAT3 to the PD-L1 gene promoter. Consistent with these findings, PD-L1 was overexpressed in NKTL cell lines harboring hotspot STAT3 mutations, and similar findings were observed by the overexpression of p.E616K and p.E616G in the STAT3 wild-type NKTL cell line. Conversely, STAT3 silencing and inhibition decreased PD-L1 expression in STAT3 mutant NKTL cell lines. In NKTL tumors, STAT3 activation correlated significantly with PD-L1 expression. We demonstrated that STAT3 activation confers high PD-L1 expression, which may promote tumor immune evasion. The combination of PD-1/PD-L1 antibodies and STAT3 inhibitors might be a promising therapeutic approach for NKTL, and possibly PTCL.

Patterns of Expression of Purinergic Receptor P2RY12, a Putative Marker for Non-Activated Microglia, in Aged and Alzheimer's Disease Brains.

Neuroinflammation is considered a key pathological process in neurodegenerative diseases of aging, including Alzheimer's disease (AD). Many studies have defined phenotypes of reactive microglia, the brain-resident macrophages, with different antigenic markers to identify those potentially causing inflammatory damage. We took an alternative approach with the goal of characterizing the distribution of purinergic receptor P2RY12-positive microglia, a marker previously defined as identifying homeostatic or non-activated microglia. We examined the expression of P2RY12 by dual-color light and fluorescence immunohistochemistry using sections of middle temporal gyrus from AD, high plaque and low plaque non-demented cases in relation to amyloid beta (Aß) plaques and phosphorylated tau, markers of pathology, and HLA-DR, IBA-1, CD68, and progranulin, microglial phenotype markers. In low plaque cases, P2RY12-positive microglia mostly had non-activated morphologies, while the morphologies of P2RY12-positive microglia in AD brains were highly variable, suggesting its expression could encompass a wider range of phenotypes than originally hypothesized. P2RY12 expression by microglia differed depending on the types of plaques or tangles they were associated with. Areas of inflammation characterized by lack of P2RY12-positive microglia around mature plaques could be observed, but many diffuse plaques showed colocalization with P2RY12-positive microglia. Based on these results, P2RY12 expression by microglia should not be considered solely a marker of resting microglia as P2RY12 immunoreactivity was identifying microglia positive for CD68, progranulin and to a limited extent HLA-DR, markers of activation.

Management of hepatitis B reactivation in lymphoma patients on rituximab with past hepatitis B exposure: An observational study.

BACKGROUND: Currently, a standardized approach to prevent and manage hepatitis B reactivation in lymphoma patients with past hepatitis exposure receiving rituximab in Singapore is lacking. This study is designed to report the current management approach and outcomes associated with hepatitis B reactivation. OBJECTIVES: The primary objective was to report 6-, 12-, 24-month cumulative hepatitis B reactivation-related outcomes. Secondary objectives were to report monitoring frequencies of hepatitis B DNA and liver function tests performed in lymphoma patients with resolved hepatitis B receiving rituximab, and anti-viral prophylaxis use. METHODOLOGY: This was a single centre, retrospective observational study. Patients with resolved hepatitis B initiated on rituximab from January 2011 to December 2015 were identified and reviewed over a two-year period starting from the date of rituximab initiation. Relevant parameters were obtained from electronic medical records. Hepatitis B reactivation was defined by hepatitis B DNA levels 20 IU/ml (1.30 log/ml) and above. Data were analysed using descriptive statistics. RESULTS: Seventy-five patients were retrospectively reviewed over a two-year period. Hepatitis B reactivation was defined as hepatitis B DNA levels ≥20 IU/ml (1.30 log/ml). The 24-month cumulative hepatitis B reactivation rate was 4.0%. The median (interquartile range) number of hepatitis B DNA tests performed during treatment, initial six-month follow-up, and subsequent follow-up were 1.0 (0.0-2.6), 1.0 (0.0-2.0), and 1.0 (0.0-3.1), respectively. CONCLUSION: Large variations in hepatitis B reactivation monitoring and management strategies were observed. Further studies are required to develop and determine a standardised protocol that could contribute to safer and more cost-effective care for lymphoma patients with resolved hepatitis B on rituximab.

Establishing normative data for the Functional Dexterity Test in typically developing children aged 3-5 years.

STUDY DESIGN: Cross-sectional. INTRODUCTION: The Functional Dexterity Test (FDT) is a timed pegboard hand dexterity test. Normative data have been developed primarily in adults with some studies in the pediatric population. The present study will complement the existing pediatric data and make the FDT a stronger assessment for use in this population. PURPOSE OF THE STUDY: The primary aim of this study was to collect normative data in typically developing children aged 3-5 years in the Greater Montreal area; the secondary aim was to evaluate the intrarater and interrater reliabilities of the FDT. METHODS: The FDT was administered to typically developing children aged 3-5 years, who were recruited from various geographical locations and socioeconomic status levels across the Greater Montreal area. Descriptive statistics, t-tests, and analysis of variance were used to compare age-gender groups. The intraclass correlation coefficient (ICC) was calculated to determine intrarater and interrater reliabilities. RESULTS: Normative data were collected from 267 children (137 females) from 18 daycares. Statistically significant differences in FDT scores were found across all age bands (P < .01). Total time decreased with increasing age (P < .01). No significant differences were found between genders. The FDT showed excellent interrater (ICC = 0.89-0.98) and intrarater (ICC = 0.83-0.99) reliabilities. CONCLUSIONS: The clear and standardized pediatric instructions, scoring sheet, and normative data table developed in this study provide health care professionals with quick and easy tools to facilitate scoring and clinical interpretation of hand dexterity in preschool-aged children. Future studies should include school-aged children and adolescents from a larger geographic area.