bluuebunny/crossref_metadata_2025 huggingface dataset:
Severe Left Atrial Spontaneous Echo Contrast in Nonvalvular Atrial Fibrillation: Clinical Characteristics and Impact on Ischemic Risk Postablation
Authors: Wang Hao , Xi Siqi , Chen Jindong , Zhao Liang , Gan Tian , He Ben
Published: November 2022

Background Spontaneous echo contrast (SEC) is an important precursor for intracardiac thrombus and stroke. There are very limited data on characteristics of severe SEC and its impact on ischemic risk of nonvalvular atrial fibrillation (NVAF) patients after radiofrequency catheter ablation.

Methods Transesophageal echocardiography files were reviewed between March 2009 and March 2021 in this monocentric retrospective study. SEC was classified into four levels. The primary endpoint was thromboembolic event (stroke, myocardial infarction, systemic embolism, and ensuing death), and the secondary endpoint included nonischemic mortality and recurrent atrial arrhythmia.

Results Six hundred SEC cases were enrolled and classified into mild SEC group (Grade 1–2, n = 515) and severe SEC group (Grade 3–4, n = 85). Independent risk factors for severe SEC included higher brain natriuretic peptide (BNP), erythrocyte sedimentation rate (ESR), and LAd/∆LVED (LAd = left atrial diameter; ∆LVED = left ventricular end-diastolic diameter − left ventricular end-systolic diameter). The severe SEC group had a higher peri-procedural ischemic event occurrence (7.1 vs. 1.9%, p = 0.007). At a median follow-up of 55 months, the severe SEC group had a lower freedom rate from ischemic events (90.1 vs. 75.3%, p < 0.001); older age and severe SEC were independent risk factors for ischemic events. In patients undergoing redo-procedure (n = 100), a remarkably reduced ESR (17.8 ± 12.0 vs. 28.2 ± 19.0 mm/h, p < 0.001) was observed in patients whose SEC disappeared.

Conclusion Higher BNP, ESR, and LAd/∆LVED were the independent predictors for severe SEC. Severe SEC was associated with higher peri-procedural and long-term ischemic risks. ESR and LAd/∆LVED, as indicators of hematological and hemodynamic change, seemed helpful in identifying NVAF patients prone to developing severe SEC.
Association between Sports Participation, Factor VIII Levels and Bleeding in Hemophilia A
Authors: Bukkems Laura H. , Versloot Olav , Cnossen Marjon H. , Jönsson Siv , Karlsson Mats O. , Mathôt Ron A.A. , Fischer Kathelijn
Published: November 2022

Background Little is known on how sports participation affects bleeding risk in hemophilia. This study aimed to examine associations between sports participation, factor VIII (FVIII) levels and bleeding in persons with hemophilia A.

Methods In this observational, prospective, single-center study, persons with hemophilia A who regularly participated in sports were followed for 12 months. The associations of patient characteristics, FVIII levels, and type/frequency of sports participation with bleeding were analyzed by repeated time-to-event modelling.

Results One hundred and twelve persons (median age: 24 years [interquartile range:16–34], 49% severe, 49% on prophylaxis) were included. During follow-up, 70 bleeds of which 20 sports-induced were observed. FVIII levels were inversely correlated with the bleeding hazard; a 50% reduction of the baseline bleeding hazard was observed at FVIII levels of 3.1 and a 90% reduction at 28.0 IU/dL. The bleeding hazard did not correlate with sports participation. In addition, severe hemophilia, prestudy annual bleeding rate, and presence of arthropathy showed a positive association with the bleeding hazard.

Conclusion This analysis showed that FVIII levels were an important determinant of the bleeding hazard, but sports participation was not. This observation most likely reflects the presence of adequate FVIII levels during sports participation in our study. Persons with severe hemophilia A exhibited a higher bleeding hazard at a similar FVIII levels than nonsevere, suggesting that the time spent at lower FVIII levels impacts overall bleeding hazard. These data may be used to counsel persons with hemophilia regarding sports participation and the necessity of adequate prophylaxis.
Impact of Dentine Pretreatment with Matrix Metalloproteinase Inhibitors on Bond Strength of Coronal Composite Restorations: A Systematic Review and Meta-analysis of In Vitro Studies
Authors: Jamal Hasan , Yaghmoor Rayan , Abed Hassan , Young Anne , Ashley Paul
Published: November 2022

Matrix metalloproteinase (MMP) enzymes participate in collagen matrix degradation, including in dentine, potentially compromising bond strength. Therefore, MMP inhibitors have been hypothesized to improve restoration bond strength and stability. This systematic review aimed to evaluate the influence of different MMP inhibitors applied as dentine surface pretreatments on the immediate (24 hours) and longer term (months) bond strength of direct coronal composite restorations. This systematic literature review followed the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) statement. A systematic literature search of three databases (Ovid MEDLINE, Ovid Embase, and Google Scholar) was conducted independently by two reviewers from inception to April 2022. An adapted quality assessment tool was independently applied by two reviewers for risk of bias assessment. RevMan v5.4 software was used for meta-analyses. A randomeffectsmodel was used to generatemean differences with 95% confidence intervals for treatment and control comparisons. The Q-test and I2-test were used to test for heterogeneity. The proportion of total variance across studies attributable to heterogeneity rather than chance was calculated. Overall effects were tested using the Z-test, while subgroup differences were tested using Chi-squared tests. Of 934 studies, 64 studies were included in the systematic review and 42 in the meta-analysis. Thirty-one MMP inhibitors were reported, three of which were included in the meta-analysis: 2% chlorhexidine (CHX), 0.3M carbodiimide (EDC), and 0.1% riboflavin (RIBO). Pretreatment with 2% CHX for 30 and 60 seconds did not significantly improve bond strength compared with controls either immediately or after long-termageing. However, pretreatment with 0.3MEDC and 0.1% RIBO (but not CHX) significantly improved bond strength compared with control groups both immediately and over time. Most studies showed a medium risk of bias. These in vitro findings pave the way for rationale clinical trialing of dentine surface pretreatment with MMP inhibitors to improve clinical outcomes.
Possible Targets to Reduce Fatigue in Chronic Immune Thrombocytopenia Patients – An Explorative Study
Authors: van Dijk Wobke E.M. , Nap-van der Vlist Merel M. , Knoop Hans , Schutgens Roger E.G.
Published: November 2022

Background Fatigue in immune thrombocytopenia (ITP) is frequent and burdensome, but we lack the knowledge to help these patients.

Aim The aim of the study is to explore the role of disease activity and other potentially modifiable factors in fatigue.

Method This cross-sectional study included adult chronic ITP patients (n = 59). Univariable linear regression (corrected for confounders) was used to determine the relationship between disease activity (platelet count <30 × 109/L or treatment), disease-specific factors (bleeding symptoms, ferritin), and transdiagnostic factors (FACT-G physical/functional/emotional/social well-being subscales, physical activity level, and vitamin D) and fatigue (Checklist Individual Strength fatigue subscale). Several multivariable models with clustered sets of variables were used to compare the proportion of explained variance of fatigue (adjusted R 2).

Results Significant relations with moderate effect sizes (>0.50) were found for physical and functional well-being and fatigue, and physical activity and fatigue. Other significant relations with fatigue (effect size 0.30–0.47) included skin and organ bleeding, emotional and social well-being, vitamin D, and disease activity. Notably, the models with disease activity and disease-specific factors explained <20% of the variance in fatigue, while the models with transdiagnostic factors (functioning and physical activity) explained >50%. Vitamin D alone explained 12% of the variance in fatigue.

Conclusion Transdiagnostic (non-disease-specific) rather than disease-specific factors explained a large part of the variance in ITP-related fatigue. Many factors related to fatigue are potentially modifiable and should be investigated as targets for interventions.
Accuracy of Ophthalmology Clinic Follow-Up in the Incarcerated Patient Population
Authors: Abou-Jaoude Michelle M. , Crawford Jessica , Kryscio Richard J. , Moore Daniel B.
Published: November 2022

Purpose Incarcerated patients represent a uniquely vulnerable population in the outpatient ophthalmology setting, and the reliability of follow-up in this group is undetermined.

Methods This was a retrospective, observational chart review of consecutive incarcerated patients evaluated at the ophthalmology clinic of a single academic medical center between July 2012 and September 2016. For each encounter the following were recorded: patient age, gender, incarcerated status at the time of encounter (a subset of patients had encounters before/after incarceration), interventions performed, follow-up interval requested, urgency of follow-up, and actual time to subsequent follow-up. Primary outcome measures were no-show rate and timeliness, which was defined as follow-up within 1.5× the requested period.

Results There were 489 patients included during the study period, representing a total of 2,014 clinical encounters. Of the 489 patients, 189 (38.7%) were seen once. Of the remaining 300 patients with more than one encounter, 184 (61.3%) ultimately did not return and only 24 (8%) were always on time for every encounter. Of 1,747 encounters with specific follow-up requested, 1,072 were considered timely (61.3%). Factors significantly associated with subsequent loss to follow-up include whether a procedure was performed (p < 0.0001), urgency of follow-up (p < 0.0001), incarcerated status (p = 0.0408), and whether follow-up was requested (p < 0.0001).

Conclusion Almost two-thirds of incarcerated patients in our population requiring repeat examination were lost to follow-up, particularly those who underwent an intervention or required more urgent follow-up. Patients entering and exiting the penal system were less likely to follow-up while incarcerated. Further work is needed to understand how these gaps compare to those in the general population and to identify means of improving these outcomes.
Reliability of the Sigmoid Notch Classification of the Distal Radioulnar Joint
Authors: D'Sa Heathcliff , Willing Ryan , Murray Tim , Rowan Kevin , Grewal Ruby , King Graham , Daneshvar Parham
Published: November 2022

Background The Tolat sigmoid notch classification is a commonly used classification to characterize the distal radioulnar joint (DRUJ). This classification was based on a limited assessment of the entire joint, which may lead to inaccuracies in sigmoid notch evaluation.

Questions/Purposes The purpose of this study is to assess the reliability of the Tolat classification for sigmoid notch characterization.

Methods The sigmoid notch of 52 models of cadaveric forearms was assessed by applying the Tolat classification to the three-dimensional (3D) modeled notch and then slices at the start of the notch (0 mm) and 4 mm more proximal. The inter- and intrarater agreement was assessed using Cohen's and Fleiss' kappa statistic.

Results Agreement between iterations regardless of slices or surgeons/radiologists was moderate. Intrarater agreement between pairs of slices (0 vs 4 mm, 0 mm vs 3D, 4 mm vs 3D) was moderate, whereas agreement between all slices was slight. Agreement between surgeons and between radiologists was moderate, while agreement across all raters and slices was fair. Models described as “other” were more consistent in 3D classifications and were commonly classified as a reverse ski slope.

Conclusions Classification using the Tolat scheme is fair to moderate at best. Classification of the sigmoid notch using an axial view of the distal radius may not accurately reflect the anatomy throughout the notch.

Clinical Relevance The Tolat classification supplies a limited analysis of the sigmoid notch, and does not represent a comprehensive evaluation of the entire joint. Future classification systems should characterize the entire sigmoid notch.
How default effects and decision timing affect annuity uptake and health consciousness
Authors: Unger Franziska , Steul-Fischer Martina , Gatzert Nadine
Published: November 2022

Annuities provide a lifelong income stream and can therefore help individuals to mitigate the risk of outliving their savings, a highly topical issue in the context of increasing life expectancies. Given that real-world annuitization rates remain relatively low, we investigate the influence of behavioral biases on people’s choice between a lifelong annuity and a lump sum payout. In so doing, we focus on the impact of default effects due to a preselected annuity option (default option) and the impact of the decision’s timing (decisions on annuitization taken by younger individuals refer to a distant future, those taken by older individuals to a near future) on annuity uptake and health consciousness. We used a scientific survey panel to conduct an online experiment with a diversified sample of 339 participants (55.2% female, average age = 42.5 years). Our results show that the timing of the decision moderates the default effect on annuity uptake, in that the effect of a preselected (default) annuity option is stronger for distant-future decisions (i.e., choice of annuity instead of lump sum at retirement made by younger participants purchasing a deferred annuity) than for near-future decisions made by older individuals who are closer to retirement. We further find that the default effect moderates health consciousness after choosing an annuity. Health consciousness is stronger in the no-default condition than in the annuity default condition.
Study of the Effect of Different Breast Implant Surfaces on Capsule Formation and Host Inflammatory Response in an Animal Model
Authors: Santanelli di Pompeo Fabio , Sorotos Michail , Canese Rossella , Valeri Mauro , Roberto Cirombella , Giorgia Scafetta , Firmani Guido , di Napoli Arianna
Published: November 2022

Background

Breast implants are biomaterials eliciting a physiological and mandatory foreign body response.

Objectives

The authors designed an animal study to investigate the impact of different implant surfaces on the formation of the periprosthetic capsule, the inflammatory response, and the cellular composition.

Methods

The authors implanted 1 scaled-down version of breast implants by different manufactures on 70 female Sprague Dawley rats. Animals were divided into 5 groups of 14 animals. Group A received a smooth implant (Ra ≈ 0.5 µm) according to the ISO 14607-2018 classification, Group B a smooth implant (Ra ≈ 3.2 µm), Group C a smooth implant (Ra ≈ 5 µm), Group D a macrotextured implant (Ra ≈ 62 µm), and Group E a macrotextured implant (Ra ≈ 75 µm). At 60 days, all animals received a magnetic resonance imaging (MRI), and 35 animals were killed and their capsules sent for histology (capsule thickness, inflammatory infiltrate) and immunohistochemistry analysis (cellular characterization). The remaining animals repeated the MRI at 120 days and were killed following the same protocol.

Results

MRI showed a thinner capsule in the smooth implants (Groups A-C) at 60 days (P < .001) but not at 120 days (P = .039), confirmed with histology both at 60 days (P = .005) and 120 days (P < .001). Smooth implants (Groups A-C) presented a mild inflammatory response at 60 days that was maintained at 120 days and a high M2-Macrophage concentration (anti-inflammatory).

Conclusions

Our study confirms that smooth implants form a thinner capsule, inferior inflammatory infiltrate, and a cellular composition that indicates a mild host inflammatory response. A new host inflammatory response classification is elaborated classifying breast implants into mild, moderate, and high.
Lewis x-carrying O-glycans are candidate modulators for conceptus attachment in pigs
Authors: Han Kun , Yue Yulu , Wang Weiwei , Wang Feiyu , Chai Wengang , Zhao Shuhong , Yu Mei
Published: November 2022

Successful attachment of conceptus to the uterine luminal epithelium (LE) is crucial for establishing a functional placenta in pigs. However, the underlying mechanisms are yet to be elucidated. The uterine LE-conceptus interface is enriched in various glycoconjugates essential to implantation. Using MALDI-MS profiling, we identified for the first time the O-glycan repertoire of pig endometrium during the conceptus attachment stage. The expression pattern of blood group A, O(H), Lewis x, y, a, b (Lex, Ley, Lea, and Leb), the sialylated and sulfated Lex antigens in the uterine LE-conceptus interface was assessed using immunofluorescence assays. Notably, the Lex-carrying O-glycans exhibited a temporal–spatial expression pattern. They were absent in the endometrium on estrous cycle days but strongly and spatially presented in the conceptus and uterine LE to which the conceptus apposes during the early conceptus attachment stage. In addition, Lex-carrying O-glycans were co-localized with secreted phosphoprotein 1 (SPP1), a well-characterized factor that plays a role in promoting conceptus attachment through interacting with integrin αVβ3 and integrin αVβ6. Meanwhile, the immunoprecipitation assays revealed an interaction between the Lex-carrying O-glycans and SPP1, integrin αV, and integrin β6. Furthermore, we provided evidence that the β1,4-galactosyltransferase 1 (B4GALT1) gene is a potential regulator for Lex antigen expression in the uterine LE-conceptus interface during the early conceptus attachment stage. In conclusion, our findings show that Lex-carrying O-glycans, presumably dependent on B4GALT1 gene expression, might modulate conceptus attachment by interacting with the SPP1-integrin receptor complex in pigs.
Why Do Chinese Older Adults in Hong Kong Delay or Refuse COVID-19 Vaccination? A Qualitative Study Based on Grounded Theory
Authors: Yuan Jiehu , Lam Wendy Wing Tak , Xiao Jingyi , Ni Michael Yuxuan , Cowling Benjamin John , Liao Qiuyan
Published: November 2022

Objectives

Older adults have been disproportionately affected by the coronavirus disease 2019 (COVID-19) pandemic. While COVID-19 vaccines are effective for reducing mortality and severe complications, vaccine hesitancy remains a substantial concern particularly among older adults. This was a qualitative study to explore how Chinese older adults reached a decision to delay or refuse the COVID-19 vaccines in Hong Kong.

Methods

Semi-structured in-depth interviews were conducted with 27 older adults aged ≥60 years who had never received COVID-19 vaccines. The grounded theory approach guided the selection of informants, data collection, data analysis, and report writing.

Results

Older adults’ vaccine hesitancy and resistance weaved into the context of lacking sufficient decisional support and attitude roots of negative perception of aging, fatalistic risk attitudes, present-oriented time perspectives, and negative values on western biomedicine. Attitude roots were used as the decisional anchors to further shape older adults’ peripheral processing of vaccine-related information, resulting into a spectrum of vaccine-resistant and vaccine-hesitant attitudes. While participants refused or delayed COVID-19 vaccination, they engaged in alternative coping strategies to regain self-control and justify their vaccination disengagement in the pandemic.

Discussion

Interventions to address vaccine hesitancy in older adults should focus on addressing attitude roots and strengthening the connectivity of older adults with family, doctors, and government to engage older adults in the vaccination decision making. Risk communication should shift to provide more personal relevant information in a caring style, meet older adults’ preference for peripheral information processing, and address their existing misperceptions about COVID-19 vaccines.
Information Visualization Dashboard to Proctor Test-Takers During an Online Language Proficiency Test
Authors: Hernández-Calderón José-Guillermo , Soto-Mendoza Valeria , Montané-Jiménez Luis-Gerardo , Alain Meunier Colula Marion , Tello - Carrillo Janeth
Published: November 2022

As a result of the COVID-19 pandemic, the learning and evaluation processes have been moved to an online modality to keep social distance and reduce the spreading of the virus. The strategies implemented for assessment and proctoring in this online remote teaching and assessment emergency are no exception when proctoring test-takers. This problem is addressed from a practical context of study: the English Language Proficiency Tests of a University in southeast Mexico. Considering an iterative user-centered mixed methodology, a set of dashboards was designed, implemented and evaluated to visualize the information generated by test-takers during the administration process. An increase in the Usability of the dashboards is observed in all heuristic categories, with visual design being greater. The use of the mixed methodology and the constant user feedback during the process helped us to reduce development time compared with other works found in the literature. Moreover, it is possible to use the proposed dashboards in other application domains like medicine, or care facilities where user activity monitoring is needed to make informed decisions.

categoryHuman-centered computing; Information visualization
Microstructural observation of the swollen catalyst layers of fuel cells by cryo-TEM
Authors: Shimanuki Junichi , Imai Hideto , Ito Yoshiko , Nishino Yuri , Miyazawa Atsuo
Published: November 2022

It is important to understand and control the fine structure of the fuel cell catalyst layer in order to improve the battery characteristics of the fuel cell. A major challenge in observing the microstructure of the catalyst layer by electron microscopy is the visualization of ionomers, which have low contrast and are susceptible to damage by electron beam irradiation. Previous papers have reported transmission electron microscopy (TEM) observations of ionomers neutralized with cesium (Cs) ions. However, this approach involves chemical reactions and indirect visualization of ionomers. In contrast, we have previously revealed the microstructure of ionomers in frozen catalyst inks by cryogenic (cryo) scanning electron microscopy and cryo-TEM. In general, ionomers are basically used under high-temperature and humid conditions while the fuel cell is operating. Therefore, in this study, ultrathin sections prepared from the fuel cell catalyst layer (membrane electrode assemblies) were incubated in a chamber under high-temperature and humid conditions and then rapidly frozen for observation by cryo-TEM. As a result, we succeeded in observing the pore structure of the catalyst layer in the swollen state of the ionomer. The swollen ionomer surrounded and enclosed the Pt/C aggregates and bridged over the pores in the catalyst layer.
A case report on a rare presentation of adrenal myelolipoma with low-impact traumatic haemorrhage and the challenges of conservative management
Authors: Paice Bronte , Oyebola Taiwo , Ball Kathryn , Alexander Shaun , Sherwood Benedict
Published: November 2022

Adrenal myelolipomas are rare, hormonally silent, adipose and myeloid-containing lesions that are mostly asymptomatic. If they do present it is usually with mass-related flank pain or spontaneous haemorrhage. A 55-year-old female presented with right flank pain after a fall from a static pushbike. Computer tomography identified a large adrenal lesion with surrounding acute retroperitoneal haemorrhage. A conservative approach to treatment was decided on as the patient remained haemodynamically stable. The patient developed a pulmonary embolism during the time of conservative management and therefore had to be anticoagulated with close monitoring. Outpatient surveillance imaging was reassuring, hormonal screening was negative and biopsy confirmed myelolipoma. We report a rare presentation of adrenal myelolipoma with the sequelae of haemorrhage from low-impact trauma and the challenges of conservative management.
Electron density variability in the day-side ionosphere of Mars: The role of gravity waves
Authors: Wang Xing , Xu Xiaojun , Cui Jun , Gu Hao , Niu Dandan , Zhou Zilu , Chang Qing , Xu Qi , Luo Lei , He Peishan , Yi Siqi
Published: November 2022

Mars Atmosphere and Volatile EvolutioN (MAVEN) has observed oscillations in the density, velocity, and temperature of ionospheric plasma on Mars. Atmospheric gravity waves can be an underlying mechanism. We propose a linearized wave–electron interaction model adopting a Wentzel–Kramers–Brillouin approximation to explore the electron density variations in the Martian day-side ionosphere for two regions, which are dominated by crustal magnetic fields and horizontal draped interplanetary magnetic fields. Our model results reveal that the electron density fluctuations associated with the crustal magnetic fields and the draped magnetic fields range from ∼ 40 per cent to ∼ 83 per cent and ∼ 29 per cent to ∼ 125 per cent, respectively. The wave-induced vertical electron flux peaks occur in a region ranging from ∼ 115 km to ∼ 179 km altitude. These results are comparable to the satellite observations. We further investigate the effect of the Martian magnetic topology on the wave-induced electron fluxes and demonstrate that the electron motions associated with the propagating gravity waves can be significantly influenced by the magnetic field orientations. The wave-induced variations in the electron temperature, ion density, and magnetic field combined with a comprehensive gravity wave model will be studied in further work.
Emerging Fusarium spp. Causing Head Blight on Hemp in Kentucky
Authors: Smith Henry , Szarka Desiree , Dixon Ed , Adedokun Oluwatoni , Munir Misbakhul , Ricciardi Magdalena , Schroer Rebecca , Gauthier Nicole
Published: November 2022

Hemp ( Cannabis sativa L.) is a versatile crop that can be used to produce a wide range of products, including food, fiber, and medicine. In 2021, U.S. hemp was valued at over $824 million. An emerging threat to hemp production in Kentucky and the southeastern United States is head blight in floral and grain hemp. During the 2020 growing season, severe losses, some as high as 100%, resulted from head blights. Necrotic floral tissues and seed heads from research trials were analyzed to confirm species identity and pathogenicity. Previously unreported causal species in Kentucky included Fusarium avenaceum, F. incarnatum-equiseti species complex, and F. sporotrichioides; F. graminearum was also confirmed. These species are known to cause head blight of cereal grains. The mycotoxin production potential of each of these species warrants further studies into the parameters that influence infection and the interaction between these Fusarium spp. and hemp.
The Impact of Colistin Resistance on the Activation of Innate Immunity by Lipopolysaccharide Modification
Authors: Avendaño-Ortiz José , Ponce-Alonso Manuel , Llanos-González Emilio , Barragán-Prada Hugo , Ballestero Luna , Lozano-Rodríguez Roberto , Márquez-Garrido Francesc J. , Hernández-Pérez José María , Morosini María-Isabel , Cantón Rafael , del Campo Rosa , López-Collazo Eduardo
Published: November 2022

Colistin resistance is caused by different lipopolysaccharide (LPS) modifications, and we propose to evaluate the effect on the innate immune response ofin vivoandin vitrocolistin resistance acquisition. We used 2 pairs of isogenic strains: (1)Escherichia coliATCC25922, susceptible to colistin and its isogenic transconjugant-carryingmcr-1 gene; and (2) OXA-48, CTX-M-15K. pneumoniaesusceptible to colistin (CS-Kp) isolated from a urinary infection and its colistin-resistant variant (CR-Kp) from the same patient after prolonged treatment with colistin. No mutation of described genes for colistin resistance (pmrA, pmrB, mgrB. phoP/QandcrrAB) were found in the CR-Kp genome; however, LPS modifications were characterized by negative-ion MALDI-TOF. The strains were co-cultured with human monocytes to determine their survival after phagocytosis and induction to apoptosis. Also, monocytes were stimulated with bacterial LPS to study cytokine and immunecheckpoint production. The addition of 4-amino-4-deoxy-l-arabinose (Ara4N) to lipid A of CR-Kp accounted for the colistin resistance. CR-Kp survived significantly longer inside human monocytes after being phagocytosed compared with the CS-Kp strain, whereas no significant differences were observed for theE. coliisogenic strains. In addition, LPS from CR-Kp induced both higher apoptosis in monocytes and higher levels of cytokine and immune checkpoint production than LPS from CS-Kp. This effect was strictly the opposite forE. coli. Our data reveal a variable impact of colistin resistance on the innate immune system, depending on the responsible mechanism. Adding Ara4N to LPS increases bacterial survival after phagocytosis and elicits a higher inflammatory response than its colistin-susceptible counterpart.
Comparative analysis of pediatric Respiratory Syncytial Virus epidemiology and clinical severity before and during the COVID-19 pandemic in British Columbia, Canada
Authors: Paramo Marina Viñeta , Abu-Raya Bahaa , Reicherz Frederic , Xu Rui Yang , Bone Jeffrey N. , Srigley Jocelyn A. , Solimano Alfonso , Goldfarb David M. , Skowronski Danuta M. , Lavoie Pascal M.
Published: November 2022

Background

The COVID-19 pandemic affected Respiratory Syncytial Virus (RSV) circulation and surveillance, causing logistical complexity for health systems. Our objective was to describe changes in epidemiology and clinical severity of RSV cases in British Columbia, Canada.

Methods

Comparative analysis of RSV detections in children <36 months at BC Children’s Hospital (BCCH) between September 1 and August 31 of 2017-18, 2018-19, 2019-20, 2020-21 and 2021-22.

Results

About one-fifth of children tested RSV positive on average across all periods. The median age of RSV cases was 11.8 [IQR: 3.8–22.3] months in 2021-22 versus 6.3 [IQR: 1.9–16.7] months in 2017-20 (p<0.001). Increased testing in 2021-22 (n=3,120) compared to 2017-20 (average n=1,222/period) detected milder infections with lower proportion hospitalized in all age subgroups <6 (26.0%), 6-11 (12.3%), 12-23 (12.2%) and 24-35 (16.0%) months versus 2017-20 (49.3%, 53.5%, 62.6%, 57.5%, respectively) (all p<0.001). Children <6 months consistently comprised most hospitalizations and those born prematurely <29 weeks or with chronic respiratory co-morbidities remained at highest hospitalization risk in 2021-22. Among hospitalized cases, intensive care, respiratory support or supplemental oxygen use did not differ between the 2017-20 and 2021-22 periods.

Conclusions

RSV circulation halted during the pandemic, but with the lifting of mitigation measures a subsequent resurgence in children <36 months of age was accompanied by shift toward older (24-35 month) cases in 2021-22, without increased severity. For the 2022-23 period, increased circulation and residual vulnerability in additional birth cohorts spared from RSV infection during the pandemic could have marked cumulative healthcare impact, even without increase in proportion hospitalized.
Distinct super-enhancer elements differentially controlIl2ragene expression in a cell-type specific fashion
Authors: Spolski Rosanne , Li Peng , Chandra Vivek , Shin Boyoung , Liu Chengyu , Oh Jangsuk , Ren Min , Enomoto Yutaka , West Erin E. , Christensen Stephen , Wan Edwin C.K. , Ge Meili , Lin Jian-Xin , Vijayanand Pandurangan , Rothenberg Ellen V. , Leonard Warren J.
Published: November 2022

The IL-2 receptor α-chain (IL-2Rα/CD25) is constitutively expressed on DN2/DN3 thymocytes and Treg cells but induced by IL-2 on mature T and NK cells.Il2raexpression is regulated by a super-enhancer extensively bound by STAT5 in mature T cells. Here, we demonstrate that STAT5 cooperates with Notch to induce/maintainIl2ra/CD25 expression in DN2/DN3 cells. Moreover, we systematically investigated CD25 regulation using a series of mice with deletions spanning STAT5 binding elements. Deleting the upstream super-enhancer region mainly affected constitutive CD25 expression on DN2/DN3 thymocytes and Tregs, whereas deleting an intronic region primarily decreased IL-2-induced CD25 on peripheral T and NK cells. Thus, distinct elements preferentially control constitutive versus inducible expression in a cell-type-specific manner, with the MED1 coactivator co-localizing with specific STAT5 binding sites. Moreover, the intronic region was a dominant element whose deletion altered the structure throughout the super-enhancer in mature T cells. These results demonstrate differential functions for distinct super-enhancer elements, thereby indicating ways to manipulate CD25 expression in a cell-type specific fashion.
Crystal structure of FAD-independent methylene-tetrahydrofolate reductase fromMycobacterium hassiacum
Authors: Gehl Manuel , Demmer Ulrike , Ermler Ulrich , Shima Seigo
Published: November 2022

FAD-independent methylene-tetrahydrofolate (methylene-H4F) reductase (Mfr), recently identified in mycobacteria, catalyzes the reduction of methylene-H4F to methyl-H4F with NADH as hydride donor by a ternary complex mechanism. This biochemical reaction corresponds to that of the ubiquitous FAD-dependent methylene-H4F reductase (MTHFR), although the latter uses a ping-pong mechanism with FAD as prosthetic group. Comparative genomics and genetic analyses indicated that Mfr is indispensable for the growth ofMycobacterium tuberculosis, which lacks the MTHFR-encoding gene. Thus, Mfr is an excellent target enzyme for the design of antimycobacterial drugs. Here, we report the heterologous production, enzymological characterization and the crystal structure of Mfr from the thermophilic mycobacteriumM. hassiacum(hMfr), which shows 78% sequence identity to Mfr fromM. tuberculosis.Although hMfr and MTHFR show very low sequence identity and different catalytic mechanisms, their tertiary structures are highly similar, which suggests a divergent evolution of Mfr and MTHFR from a common ancestor. Most of the important active-site residues of MTHFR are conserved and equivalently positioned in the tertiary structure of hMfr. The Glu9Gln variant of hMfr exhibits a drastic reduction of the catalytic activity, which supports the predicted function of the glutamate residue as proton donor in both Mfr and MTHFR. The predicted nicotinamide binding site of hMfr is substantially narrower than the isoalloxazine binding site of MTHFR, which may reflect an evolutional adaptation to the different sizes of the coenzymes.
Cystatin F(Cst7)drives sex-dependent changes in microglia in an amyloid-driven model of Alzheimer’s Disease
Authors: Daniels Michael J. D. , Lefevre Lucas , Szymkowiak Stefan , Drake Alice , McCulloch Laura , Tzioras Makis , Barrington Jack , Dando Owen R. , He Xin , Mohammad Mehreen , Sasaguri Hiroki , Saito Takashi , Saido Takaomi C. , Spires-Jones Tara L. , McColl Barry W.
Published: November 2022

Microglial endolysosomal (dys)function is strongly implicated in neurodegeneration. Transcriptomic studies show that a microglial state characterised by a set of genes involved in endolysosomal function is induced in both mouse Alzheimer’s Disease (AD) models and in human AD brain and that the onset of this state is emphasized in females.Cst7(encoding protein Cystatin F) is among the most highly upregulated genes in these microglia. However, despite such striking and robust upregulation, the sex-specific function ofCst7in neurodegenerative disease is not understood. Here, we crossedCst7−/−mice with theAppNL-G-Fmouse to test the role ofCst7in a model of amyloid-driven AD. Surprisingly, we found thatCst7plays a sexually dimorphic role regulating microglia in this model. In females,Cst7-deficient microglia had greater endolysosomal gene expression, lysosomal burden, and amyloid beta (Aβ) burdenin vivoand were more phagocyticin vitro. However, in males,Cst7-deficient microglia were less inflammatory and had a reduction in lysosomal burden but had no change in Aβ burden. This study has important implications for AD research, confirming the functional role of a gene which is commonly upregulated in disease models, but also raising crucial questions on sexual dimorphism in neurodegenerative disease and the interplay between endolysosomal and inflammatory pathways in AD pathology.
Deducing ensemble dynamics and information flow from the whole-brain imaging data
Authors: Toyoshima Yu , Sato Hirofumi , Nagata Daiki , Kanamori Manami , Jang Moon Sun , Kuze Koyo , Oe Suzu , Teramoto Takayuki , Iwasaki Yuishi , Yoshida Ryo , Ishihara Takeshi , Iino Yuichi
Published: November 2022

Recent development of large-scale activity imaging of neuronal ensembles provides opportunities for understanding how activity patterns are generated in the brain and how information is transmitted between neurons or neuronal ensembles. However, methodologies for extracting the component properties that generate overall dynamics are still limited. In this study, the results of time-lapse 3D imaging (4D imaging) of head neurons of the nematodeC. eleganswere analyzed by hitherto unemployed methodologies.

By combining time-delay embedding with independent component analysis, the whole-brain activities were decomposed to a small number of component dynamics. Results from multiple samples, where different subsets of neurons were observed, were further combined by matrix factorization, revealing common dynamics from neuronal activities that are apparently divergent across sampled animals. By this analysis, we could identify components that show common relationships across different samples and those that show relationships distinct between individual samples.

We also constructed a network model building on time-lagged prediction models of synaptic communications. This was achieved by dimension reduction of 4D imaging data using the general framework gKDR (gradient kernel dimension reduction). The model is able to decompose basal dynamics of the network. We further extended the model by incorporating probabilistic distribution, resulting in models that we call gKDR-GMM and gKDR-GP. The models capture the overall relationships of neural activities and reproduce the stochastic but coordinated dynamics in the neural network simulation. By virtual manipulation of individual neurons and synaptic contacts in this model, information flow could be estimated from whole-brain imaging results.
FreiBox: A versatile open-source behavioral setup for investigating the neuronal correlates of behavioral flexibility via 1-photon imaging in freely moving mice
Authors: Crompe Brice De La , Schneck Megan , Steenbergen Florian , Schneider Artur , Diester Ilka
Published: November 2022

To survive in a complex and changing environment, animals must adapt their behavior. This ability is called behavioral flexibility and is classically evaluated by a reversal learning paradigm. During such a paradigm, the animals adapt their behavior according to a change of the reward contingencies. To study these complex cognitive functions (from outcome evaluation to motor adaptation), we developed a versatile, low-cost, open-source platform, allowing us to investigate the neuronal correlates of behavioral flexibility with 1-photon calcium imaging. This platform consists of FreiBox, a novel low-cost Arduino behavioral setup, as well as further open-source tools which we developed and integrated into our framework. FreiBox is controlled by a custom Python interface and integrates a new licking sensor (Strain Gauge lickometer) for controlling spatial licking behavioral tasks. In addition to allowing both discriminative and serial reversal learning, the Arduino can track mouse licking behavior in real time to control task events in a sub-millisecond timescale. To complete our setup, we also developed and validated an affordable commutator, crucial for recording calcium imaging with the Miniscope V4 in freely moving mice. Further, we demonstrated that FreiBox can be associated with 1-photon imaging and other open-source initiatives (e.g., Open Ephys), to form a versatile platform for exploring the neuronal substrates of licking based behavioral flexibility in mice. The combination of the FreiBox behavioral setup and our low-cost commutator represents a highly competitive and complementary addition to the recently emerging battery of open-source initiatives.

Significance Statement

Behavioral flexibility is essential to survive in a complex and changing environment. To study this cognitive ability in freely-moving mice, we developed a versatile, low-cost, open-source behavioral setup, called FreiBox, allowing us to investigate the neuronal correlates of licking-based behavioral flexibility. FreiBox is controlled by a custom Python interface and integrates a new licking sensor for controlling spatial licking behavioral tasks (e.g. discriminative learning, reversal learning). We also developed and validated an active commutator to record calcium imaging with the Miniscope V4 in freely moving mice. Finally, we demonstrated that FreiBox can be associated with 1-photon imaging and other open-source initiatives, to form a versatile platform for exploring the neuronal substrates of licking based behavioral flexibility in mice.
Replication-induced DNA secondary structures drive fork uncoupling and breakage
Authors: Williams Sophie L. , Casas-Delucchi Corella S. , Raguseo Federica , Guneri Dilek , Li Yunxuan , Minamino Masashi , Fletcher Emma Elisabeth , Yeeles Joseph T. P. , Keyser Ulrich F. , Waller Zoë A. E. , Antonio Marco Di , Coster Gideon
Published: November 2022

Sequences that can form DNA secondary structures, such as G-quadruplexes (G4s) and intercalated-Motifs (iMs), are abundant in the human genome and play a range of physiological roles. However, they can also pose a challenge to the replication machinery and in turn threaten genome stability. Multiple lines of evidence suggest G4s interfere with replication, but the underlying mechanism remains unclear. Moreover, there is a lack of evidence of how iMs affect the replisome. Here, we reconstitute replication of physiologically derived structure-forming sequences to find that a single G4 or iM is sufficient to arrest DNA replication. Direct single molecule structure detection within solid-state nanopores reveals structures form as a consequence of replication. A combination of genetic and biophysical characterisation establishes that structure forming capacity is a key determinant of replisome arrest. Mechanistically, replication fork arrest is caused by impaired synthesis, resulting in helicase-polymerase uncoupling. Significantly, iMs also induce breakage of nascent DNA. Finally, stalled forks are only rescued by a specialised helicase, Pif1, but not Sgs1 or Chl1. Altogether, this study provides a potential mechanism for quadruplex structure formation and resolution during replication and highlights G4s and iMs as endogenous sources of replication stress, which may explain their genomic instability and mutation frequencies in cancer.
Voltage-gated sodium channel activity mediates sea urchin larval skeletal patterning through spatial regulation of Wnt5 expression
Authors: Thomas Christopher F. , Hawkins Dakota Y. , Skidanova Viktoriya , Marrujo Simone R. , Gibson Janay , Ye Ziqing , Bradham Cynthia A.
Published: November 2022

Defining pattern formation mechanisms during embryonic development is important for understanding the etiology of birth defects and to inform tissue engineering approaches. In this study, we used tricaine, a voltage-gated sodium channel (VGSC) inhibitor, to show that VGSC activity is required for normal skeletal patterning inLytechinus variegatussea urchin larvae. We demonstrate that tricaine-mediated patterning defects are rescued by an anesthetic-insensitive version of the VGSC LvScn5a. Expression of this channel is enriched in the ventrolateral ectoderm where it spatially overlaps with posterolaterally expressed Wnt5. We show that VGSC activity is required to spatially restrict Wnt5 expression to this ectodermal region that is adjacent and instructive to clusters of primary mesenchymal cells that initiate secretion of the larval skeleton as triradiates. Tricaine-mediated Wnt5 spatial expansion correlates with the formation of ectopic PMC clusters and triradiates. These defects are rescued by Wnt5 knock down, indicating that the spatial expansion Wnt5 is responsible for the patterning defects induced by VGSC inhibition. These results demonstrate a novel connection between bioelectrical status and the spatial control of patterning cue expression during embryonic pattern formation.

Summary statement

Inhibition of voltage-gated sodium channels perturbs Wnt5-mediated patterning of the sea urchin larval skeleton
Characterizing a century of genetic diversity and contemporary antigenic diversity of N1 neuraminidase in IAV from North American swine
Authors: Hufnagel David E. , Young Katharine M. , Arendsee Zebulun , Gay L. Claire , Caceres C. Joaquin , Rajão Daniela S. , Perez Daniel R. , Vincent Baker Amy L. , Anderson Tavis K.
Published: November 2022

Influenza A viruses (IAV) of the H1N1 classical swine lineage became endemic in North American swine following the 1918 pandemic. Additional human-to-swine transmission events after 1918, and a spillover of H1 viruses from wild birds in Europe, potentiated a rapid increase in genomic diversity via reassortment between introductions and the endemic classical swine lineage. To determine mechanisms affecting reassortment and evolution, we conducted a phylogenetic analysis of N1 and paired HA swine IAV genes in North America between 1930 and 2020. We described fourteen N1 clades within the N1 Eurasian avian lineage (including the N1 pandemic clade) and the N1 classical swine lineage. Seven N1 genetic clades had evidence for contemporary circulation. To assess antigenic drift associated with N1 genetic diversity, we generated a panel of representative swine N1 antisera and quantified the antigenic distance between wild-type viruses using enzyme-linked lectin assays and antigenic cartography. Within the N1 lineage, antigenic similarity was variable and reflected shared evolutionary history. Sustained circulation and evolution of N1 genes in swine had resulted in significant antigenic distance between the N1 pandemic clade and classical swine lineage. We also observed a significant increase in the rate of evolution in the N1 pandemic clade relative to the classical lineage. Between 2010 and 2020, N1 clades and N1-HA pairings fluctuated in detection frequency across North America, with hotspots of diversity generally appearing and disappearing within two years. We also identified frequent N1-HA reassortment events (n = 36), which were rarely sustained (n = 6) and sometimes also concomitant with the emergence of new N1 genetic clades (n = 3). These data form a baseline from which we can identify N1 clades that expand in range or genetic diversity that may impact viral phenotypes or vaccine immunity and subsequently the health of North American swine.