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APOBEC3C Tandem Domain Proteins Create Super Restriction Factors against HIV-1

ABSTRACT

Humans encode proteins, called restriction factors, that inhibit replication of viruses such as HIV-1. The members of one family of antiviral proteins, apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3; shortened here to A3), act by deaminating cytidines to uridines during the reverse transcription reaction of HIV-1. The A3 locus encodes seven genes, named A3A to A3H. These genes have either one or two cytidine deaminase domains, and several of these A3s potently restrict HIV-1. A3C, which has only a single cytidine deaminase domain, however, inhibits HIV-1 only very weakly. We tested novel double domain protein combinations by genetically linking two A3C genes to make a synthetic tandem domain protein. This protein created a "super restriction factor" that had more potent antiviral activity than the native A3C protein, which correlated with increased packaging into virions. Furthermore, disabling one of the active sites of the synthetic tandem domain protein resulted in an even greater increase in the antiviral activity—recapitulating a similar evolution seen in A3F and A3G (double domain A3s that use only a single catalytically active deaminase domain). These A3C tandem domain proteins do not have an increase in mutational activity but instead inhibit formation of reverse transcription products, which correlates with their ability to form large higher-order complexes in cells. Finally, the A3C-A3C super restriction factor largely escaped antagonism by the HIV-1 viral protein Vif.

IMPORTANCE As a part of the innate immune system, humans encode proteins that inhibit viruses such as HIV-1. These broadly acting antiviral proteins do not protect humans from viral infections because viruses encode proteins that antagonize the host antiviral proteins to evade the innate immune system. One such example of a host antiviral protein is APOBEC3C (A3C), which weakly inhibits HIV-1. Here, we show that we can improve the antiviral activity of A3C by duplicating the DNA sequence to create a synthetic tandem domain and, furthermore, that the proteins thus generated are relatively resistant to the viral antagonist Vif. Together, these data give insights about how nature has evolved a defense against viral pathogens such as HIV.




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Study: Drivers who drink but arent legally impaired cause thousands of deaths

Drivers with blood-alcohol levels below legal limits cause 15% of all crash deaths that involve alcohol, a study in the March issue of the American Journal of Preventive Medicine finds.




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Engaging the Power of Communities for Better Health

Authentically engaging community residents is necessary to impact social drivers of health. Acknowledging the value of residents' lived experiences in the planning, implementation, and financial decisions of community engagement initiatives is key. Sustainability of community engagement initiatives depends on open communication and follow-through on commitments.




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Gathering Trauma Narratives: A Qualitative Study on the Impact of Self-Identified Traumas on People Living with HIV (PLWH)

BACKGROUND Trauma—emotional, physical, and psychological—is common and associated with increased risk behaviors, low rates of care engagement and viral suppression, and overall poor health outcomes for people living with HIV (PLWH). This article presents the results of 15 in-depth, semi-structured interviews with PLWH in the Southeastern United States in which participants identified a trauma and described its long-lasting impact on their lives. Participants' trauma narratives described a wide range of traumas, including childhood sexual abuse, the loss of a loved one, and their HIV diagnosis.

METHODS Systematic qualitative analysis was used to delineate beliefs about causes, symptoms, treatments, quality of life, and health implications of trauma.

RESULTS: Fifteen participants completed semi-structured interviews that lasted on average 32 minutes. Participants described a wide spectrum of personal trauma that occurred both prior and subsequent to their HIV diagnosis. The types of trauma identified included physical, sexual, and psychological abuse inflicted by intimate partners, family members, and/or strangers.

LIMITATIONS A chief limitation of this study is selection bias. Additionally, the participant selection and content of the trauma narratives might have been affected by the surrounding context of the parent study centered on HIV, aging, and psychosocial stress. It is also difficult to interpret the distinction between discrete trauma experiences and the diagnosis of HIV, leading to potential information bias.

CONCLUSION This study highlights the importance of social support in coping with trauma and the effect of trauma on health-related behaviors. It also illustrates the need for additional research on the topic of trauma and trauma-informed care for PLWH. Understanding how different types of trauma affect individuals' lives is necessary to inform recommendations to provide better care for PLWH.




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Rupture geometries in anisotropic amphibolite recorded by pseudotachylytes in the Gairloch Shear Zone, NW Scotland

Recent earthquakes involving complex multi-fault rupture have increased our appreciation of the variety of rupture geometries and fault interactions that occur within the short duration of coseismic slip. Geometrical complexities are intrinsically linked with spatially heterogeneous slip and stress drop distributions, and hence need incorporating into seismic hazard analysis. Studies of exhumed ancient fault zones facilitate investigation of rupture processes in the context of lithology and structure at seismogenic depths. In the Gairloch Shear Zone, NW Scotland, foliated amphibolites host pseudotachylytes that record rupture geometries of ancient low-magnitude (≤MW 3) seismicity. Pseudotachylyte faults are commonly foliation parallel, indicating exploitation of foliation planes as weak interfaces for seismic rupture. Discordance and complexity are introduced by fault segmentation, stepovers, branching and brecciated dilational volumes. Pseudotachylyte geometries indicate that slip nucleation initiated simultaneously across several parallel foliation planes with millimetre and centimetre separations, leading to progressive interaction and ultimately linkage of adjacent segments and branches within a single earthquake. Interacting with this structural control, a lithological influence of abundant low disequilibrium melting-point amphibole facilitated coseismic melting, with relatively high coseismic melt pressure encouraging transient dilational sites. These faults elucidate controls and processes that may upscale to large active fault zones hosting major earthquake activity.

Supplementary material: Supplementary Figures 1 and 2, unannotated versions of field photographs displayed in Figures 4a and 5 respectively, are available at https://doi.org/10.6084/m9.figshare.c.4573256

Thematic collection: This article is part of the SJG Collection on Early-Career Research available at: https://www.lyellcollection.org/cc/SJG-early-career-research




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The BIR2/BIR3-Associated Phospholipase D{gamma}1 Negatively Regulates Plant Immunity

Plants have evolved effective strategies to defend themselves against pathogen invasion. Starting from the plasma membrane with the recognition of microbe-associated molecular patterns (MAMPs) via pattern recognition receptors, internal cellular signaling pathways are induced to ultimately fend off the attack. Phospholipase D (PLD) hydrolyzes membrane phospholipids to produce phosphatidic acid (PA), which has been proposed to play a second messenger role in immunity. The Arabidopsis (Arabidopsis thaliana) PLD family consists of 12 members, and for some of these, a specific function in resistance toward a subset of pathogens has been shown. We demonstrate here that Arabidopsis PLD1, but not its close homologs PLD2 and PLD3, is specifically involved in plant immunity. Genetic inactivation of PLD1 resulted in increased resistance toward the virulent bacterium Pseudomonas syringae pv. tomato DC3000 and the necrotrophic fungus Botrytis cinerea. As pld1 mutant plants responded with elevated levels of reactive oxygen species to MAMP treatment, a negative regulatory function for this PLD isoform is proposed. Importantly, PA levels in pld1 mutants were not affected compared to stressed wild-type plants, suggesting that alterations in PA levels are not likely the cause for the enhanced immunity in the pld1 line. Instead, the plasma-membrane-attached PLD1 protein colocalized and associated with the BAK1-INTERACTING RECEPTOR-LIKE KINASES BIR2 and BIR3, which are known negative regulators of pattern-triggered immunity. Moreover, complex formation of PLD1 and BIR2 was further promoted upon MAMP treatment. Hence, we propose that PLD1 acts as a negative regulator of plant immune responses in complex with immunity-related proteins BIR2 and BIR3.




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The Calcium Sensor CBL2 and Its Interacting Kinase CIPK6 Are Involved in Plant Sugar Homeostasis via Interacting with Tonoplast Sugar Transporter TST2

Calcineurin B-like protein (CBL) and CBL-interacting protein kinase (CIPK)-mediated calcium signaling has been widely reported to function in plant development and various stress responses, particularly in ion homeostasis. Sugars are the most important primary metabolites, and thus sugar homeostasis requires precise regulation. Here, we describe a CBL2-CIPK6-Tonoplast-Localized Sugar Transporter2 (TST2) molecular module in cotton (Gossypium hirsutum) that regulates plant sugar homeostasis, in particular Glc homeostasis. GhCIPK6 is recruited to the tonoplast by GhCBL2 and interacts with the tonoplast-localized sugar transporter GhTST2. Overexpression of either GhCBL2, GhCIPK6, or GhTST2 was sufficient to promote sugar accumulation in transgenic cotton, whereas RNAi-mediated knockdown of GhCIPK6 expression or CRISPR-Cas9-mediated knockout of GhTST2 resulted in significantly decreased Glc content. Moreover, mutation of GhCBL2 or GhTST2 in GhCIPK6-overexpressing cotton reinstated sugar contents comparable to wild-type plants. Heterologous expression of GhCIPK6 in Arabidopsis (Arabidopsis thaliana) also promoted Glc accumulation, whereas mutation of AtTST1/2 in GhCIPK6-overexpressing Arabidopsis similarly reinstated wild-type sugar contents, thus indicating conservation of CBL2-CIPK6-TST2-mediated sugar homeostasis among different plant species. Our characterization of the molecular players behind plant sugar homeostasis may be exploited to improve sugar contents and abiotic stress resistance in plants.




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Transcription Factors BLH2 and BLH4 Regulate Demethylesterification of Homogalacturonan in Seed Mucilage

The polysaccharide pectin is a major component of the plant cell wall. The pectic glycan homogalacturonan (HG) is a proportionally small but important component of a specialized seed cell wall called mucilage. HG is synthesized in a highly methylesterified form, and, following secretion, is de-methylesterified by pectin methylesterases (PMEs). The degree of methylesterification of HG determines the structural and functional properties of pectin, but how methylesterification is regulated remains largely unknown. Here, we identified two BEL1-Like homeodomain (BLH) transcription factors, BLH2 and BLH4, as positive regulators of HG de-methylesterification in Arabidopsis (Arabidopsis thaliana) seed coat mucilage. BLH2 and BLH4 were significantly expressed in mucilage secretory cells during seed mucilage production. BLH2 and BLH4 single mutants exhibited no obvious mucilage phenotype, but the blh2 blh4 double mutant displayed significantly reduced mucilage adherence to the seed. Reduced mucilage adherence in blh2 blh4 was caused by decreased PME activity in the seed coat, which increased the degree of methylesterification of HG in mucilage. The expression of several PME metabolism-related genes, including PME58, PECTIN METHYLESTERASE INHIBITOR6, SEEDSTICK, and MYB52 was significantly altered in blh2 blh4 seeds. BLH2 and BLH4 directly activated PME58 expression by binding to its TGACAGGT cis-element. Moreover, pme58 mutants exhibited reduced mucilage adherence similar to that of blh2 blh4, and the blh2 blh4 pme58 triple mutant exhibited no additional mucilage adherence defects. Furthermore, overexpression of PME58 in blh2 blh4 rescued the mucilage adherence defect. Together, these results demonstrate that BLH2 and BLH4 redundantly regulate de-methylesterification of HG in seed mucilage by directly activating PME58.




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From Fuzz to Fiber: Identification of Genes Involved in Cotton Fiber Elongation




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CBL2-CIPK6-TST2-Mediated Regulation of Sugar Homeostasis




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Overcoming Algal Vitamin B12 Auxotrophy by Experimental Evolution




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The ERS approach to e-cigarettes is entirely rational

The call for the European Respiratory Society (ERS) to change their e-cigarette and vaping policy, from honourable people with decades of experience fighting the evils of tobacco, is unfortunately misconceived. The three issues of greatest concern are acute toxicity, chronic toxicity and, most importantly, the effects on children and young people. The efficacy of e-cigarettes as an adjunct to smoking cessation are outwith the expertise of paediatric specialists, but we would ask for assurances that any benefits really do outweigh the risks to children and young people (below). Our comments on these key issues are as follows:




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A rational approach to e-cigarettes: challenging ERS policy on tobacco harm reduction

We wish to thank J. Britton and co-workers for responding to our editorial and giving us an opportunity to clarify our position as well as correct a few misunderstandings. We definitely share the same goal, which is to relieve Europe and the rest of the world from the terrible results of the tobacco epidemic. We also do not "blankly oppose e-cigarettes"; however, we strongly advocate against a harm reduction strategy including e-cigarettes as well as heated tobacco products [1]. As clinicians we all see reluctant smokers where e-cigarettes can be tried as a last resort for getting off cigarette smoking, but that is of little relevance for a general harm reduction strategy. We also agree that the UK has achieved a lot in the area of smoking cessation but would argue that this has been achieved by impressive tobacco control, not by the use of e-cigarettes, and that a country such as Australia, which has banned nicotine-containing e-cigarettes, has achieved similar results.




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A rational approach to e-cigarettes: challenging ERS policy on tobacco harm reduction

The respiratory community is united in its desire to reduce and eliminate the harm caused by tobacco smoking, which is at present on course to kill one billion people in the 21st century. The stated policy of the European Respiratory Society is to strive "constantly to promote strong and evidence-based policies to reduce the burden of tobacco related diseases". In our view, the recent ERS Tobacco Control Committee statement on tobacco harm reduction [1], though well-intentioned, appears to be based on a number of false premises and draws its conclusions from a partial account of available data. It also presents a false dichotomy between the provision of "conventional" tobacco control and harm reduction approaches. We therefore respond, in turn, to the seven arguments presented against the adoption of harm reduction in the Committee's statement.




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Children With Intellectual and Developmental Disabilities as Organ Transplantation Recipients

The demand for transplantable solid organs far exceeds the supply of deceased donor organs. Patient selection criteria are determined by individual transplant programs; given the scarcity of solid organs for transplant, allocation to those most likely to benefit takes into consideration both medical and psychosocial factors. Children with intellectual and developmental disabilities have historically been excluded as potential recipients of organ transplants. When a transplant is likely to provide significant health benefits, denying a transplant to otherwise eligible children with disabilities may constitute illegal and unjustified discrimination. Children with intellectual and developmental disabilities should not be excluded from the potential pool of recipients and should be referred for evaluation as recipients of solid organ transplants.




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Ames SG, Davis BS, Marin JR, L. Fink EL, Olson LM, Gausche-Hill M, Kahn JM. Emergency Department Pediatric Readiness and Mortality in Critically Ill Children. Pediatrics. 2019;144(3):e20190568




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Ahmed A, Fend PI, Gaensbauer JT, Reves RR, Khurana R, Salcedo K, Punnoose R, Katz DJ, for the TUBERCULOSIS EPIDEMIOLOGIC STUDIES CONSORTIUM. Interferon-{gamma} Release Assays in Children <15 Years of Age. Pediatrics. 2020:145(1):e20191930




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Parental Considerations Regarding Cure and Late Effects for Children With Cancer

BACKGROUND:

More than 80% of children with cancer become long-term survivors, yet most survivors experience late effects of treatment. Little is known about how parents and physicians consider late-effects risks against a potential survival benefit when making treatment decisions.

METHODS:

We used a discrete choice experiment to assess the importance of late effects on treatment decision-making and acceptable trade-offs between late-effects risks and survival benefit. We surveyed 95 parents of children with cancer and 41 physicians at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center to assess preferences for 5 late effects of treatment: neurocognitive impairment, infertility, cardiac toxicity, second malignancies, and impaired growth and development.

RESULTS:

Each late effect had a statistically significant association with treatment choice, as did survival benefit (P < .001). Avoidance of severe cognitive impairment was the most important treatment consideration to parents and physicians. Parents also valued cure and decreased risk of second malignancies; physician decision-making was driven by avoidance of second malignancies and infertility. Both parents and physicians accepted a high risk of infertility (parents, a 137% increased risk; physicians, an 80% increased risk) in exchange for a 10% greater chance of cure.

CONCLUSIONS:

Avoidance of severe neurocognitive impairment was the predominant driver of parent and physician treatment preferences, even over an increased chance of cure. This highlights the importance of exploring parental late-effects priorities when discussing treatment options.




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E-cigarette or Vaping Product Use-Associated Lung Injury (EVALI) Without Respiratory Symptoms

Electronic cigarette or vaping product use–associated lung injury (EVALI) is a newly emerging diagnosis in the United States, yet the incidence has surged greatly in the past year. With the trend of using electronic cigarettes (e-cigarettes) and vaping rising at an alarming rate among teenagers, many are resorting to friends, illicit drug dealers, and other informal sources to obtain their e-cigarettes, which is greatly contributing to the national outbreak of EVALI. The incidence of adolescents presenting with the constellation of respiratory, gastrointestinal, and constitutional symptoms characteristic of EVALI has been widely reported within the nation. We present one such case of an adolescent boy with a 2-year history of daily vaping who presented with nausea, vomiting, weight loss, and fever but lacked the respiratory symptoms that have been reported in the majority of EVALI cases reported thus far. Computed tomography scan of the abdomen and pelvis revealed an incidental finding of lung pathology characteristic of EVALI, prompting further workup and diagnosis of EVALI. In this case, it is demonstrated that the presentation of EVALI can be variable and is still poorly defined. The rising morbidity and mortality from EVALI reveal the importance of considering EVALI in all patients with a history of vaping or e-cigarette use, regardless of the presence or absence of respiratory symptoms.




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Intramuscular Hematoma as a Manifestation of IgA Vasculitis

We describe an atypical pediatric case of immunoglobulin A vasculitis (IgAV), also referred to as Henoch-Schönlein purpura, in which formation of spontaneous hematoma of the paraspinal muscles developed. Spontaneous or unprovoked hematomas rarely occur in IgAV. These manifestations have not been described specifically in the pediatric literature as coinciding with IgAV. These findings are alarming for nonaccidental trauma, particularly in a patient without underlying blood dyscrasia. Our objective for this report is to highlight the possible association of muscular hematoma formation with IgAV and to help providers consider this association when trauma and hemophilia has been ruled out.




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E-cigarette Product Characteristics and Subsequent Frequency of Cigarette Smoking

BACKGROUND:

There is a dearth of evidence regarding the association of use of electronic cigarettes (e-cigarettes) with certain product characteristics and adolescent and young adult risk of unhealthy tobacco use patterns (eg, frequency of combustible cigarette smoking), which is needed to inform the regulation of e-cigarettes.

METHODS:

Data were collected via an online survey of participants in the Southern California Children’s Health Study from 2015 to 2016 (baseline) and 2016 to 2017 (follow-up) (N = 1312). We evaluated the association of binary categories of 3 nonmutually exclusive characteristics of the e-cigarette used most frequently with the number of cigarettes smoked in the past 30 days at 1-year follow-up. Product characteristics included device (vape pen and/or modifiable electronic cigarette [mod]), use of nicotine in electronic liquid (e-liquid; yes or no), and use for dripping (directly dripping e-liquid onto the device; yes or no).

RESULTS:

Relative to never e-cigarette users, past-30-day e-cigarette use was associated with greater frequency of past-30-day cigarette smoking at follow-up. Among baseline past-30-day e-cigarette users, participants who used mods (versus vape pens) smoked >6 times as many cigarettes at follow-up (mean: 20.8 vs 1.3 cigarettes; rate ratio = 6.33; 95% confidence interval: 1.64–24.5) after adjustment for sociodemographic characteristics, baseline frequency of cigarette smoking, and number of days of e-cigarette use. After adjustment for device, neither nicotine e-liquid nor dripping were associated with frequency of cigarette smoking.

CONCLUSIONS:

Baseline mod users (versus vape pen users) smoked more cigarettes in the past 30 days at follow-up. Regulation of e-cigarette device type warrants consideration as a strategy to reduce cigarette smoking among adolescents and young adults who vape.




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In Utero Antidepressants and Neurodevelopmental Outcomes in Kindergarteners

OBJECTIVES:

To determine if in utero selective serotonin reuptake inhibitor (SSRI) or selective serotonin norepinephrine inhibitor (SNRI) exposure is associated with developmental vulnerability in kindergarten among children whose mothers were diagnosed with prenatal mood or anxiety disorder.

METHODS:

Linkable administrative data were used to create a population-based cohort of 266 479 mother-child dyads of children born in Manitoba, Canada, between 1996 and 2014, with follow-up through 2015. The sample was restricted to mothers who had a mood or anxiety disorder diagnosis between 90 days before conception (N = 13 818). Exposed women had ≥2 SSRI or SNRI dispensations during pregnancy (n = 2055); unexposed mothers did not have a dispensation of an SSRI or SNRI during pregnancy (n = 10 017). The Early Development Instrument (EDI) was used to assess developmental health in kindergarten children. The EDI is a 104-component kindergarten teacher-administered questionnaire, encompassing 5 developmental domains.

RESULTS:

Of the 3048 children included in the study who met inclusion criteria and had an EDI, 21.43% of children in the exposed group were assessed as vulnerable on 2 or more domains versus 16.16% of children in the unexposed group (adjusted odds ratio = 1.43; 95% confidence interval 1.08–1.90). Children in the exposed group also had a significant risk of being vulnerable in language and/or cognition (adjusted odds ratio = 1.40; 95% confidence interval 1.03–1.90).

CONCLUSIONS:

Exposure to SSRIs or SNRIs during pregnancy was associated with an increased risk of developmental vulnerability and an increased risk of deficits in language and/or cognition. Replication of results is necessary before clinical implications can be reached.




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Pits and CtBP Control Tissue Growth in Drosophila melanogaster with the Hippo Pathway Transcription Repressor Tgi [Developmental and Behavioral Genetics]

The Hippo pathway is an evolutionarily conserved signaling network that regulates organ size, cell fate, and tumorigenesis. In the context of organ size control, the pathway incorporates a large variety of cellular cues, such as cell polarity and adhesion, into an integrated transcriptional response. The central Hippo signaling effector is the transcriptional coactivator Yorkie, which controls gene expression in partnership with different transcription factors, most notably Scalloped. When it is not activated by Yorkie, Scalloped can act as a repressor of transcription, at least in part due to its interaction with the corepressor protein Tgi. The mechanism by which Tgi represses transcription is incompletely understood, and therefore we sought to identify proteins that potentially operate together with Tgi. Using an affinity purification and mass-spectrometry approach we identified Pits and CtBP as Tgi-interacting proteins, both of which have been linked to transcriptional repression. Both Pits and CtBP were required for Tgi to suppress the growth of the Drosophila melanogaster eye and CtBP loss suppressed the undergrowth of yorkie mutant eye tissue. Furthermore, as reported previously for Tgi, overexpression of Pits repressed transcription of Hippo pathway target genes. These findings suggest that Tgi might operate together with Pits and CtBP to repress transcription of genes that normally promote tissue growth. The human orthologs of Tgi, CtBP, and Pits (VGLL4, CTBP2, and IRF2BP2) have previously been shown to physically and functionally interact to control transcription, implying that the mechanism by which these proteins control transcriptional repression is conserved throughout evolution.




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Surfactant Protein-A Protects against IL-13-Induced Inflammation in Asthma [MUCOSAL IMMUNOLOGY]

Key Points

  • SP-A is a collectin and plays a key role in innate immunity in the lung.

  • SP-A modulates inflammation in airway epithelial cells from patients with asthma.

  • SP-A modulates IL-13–induced inflammation through downstream IL-6/STAT3 signaling.




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    Leishmania donovani Subverts Host Immune Response by Epigenetic Reprogramming of Macrophage M(Lipopolysaccharides + IFN-{gamma})/M(IL-10) Polarization [INFECTIOUS DISEASE AND HOST RESPONSE]

    Key Points

  • L. donovani induces histone lysine methyltransferases/demethylases in the host.

  • L. donovani–induced epigenetic enzymes induce host M(IL-10) polarization.

  • Knockdown of epigenetic enzymes inhibited parasite multiplication in infected host.




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    T Follicular Helper Cells Regulate Humoral Response for Host Protection against Intestinal Citrobacter rodentium Infection [INFECTIOUS DISEASE AND HOST RESPONSE]

    Key Points

  • Lack of Tfh cells renders the mice susceptible to C. rodentium infection.

  • Tfh cell–dependent protective Abs are essential to control C. rodentium.

  • Tfh cells regulate IgG1 response to C. rodentium infection.




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    Cytomegalovirus Coinfection Is Associated with Increased Vascular-Homing CD57+ CD4 T Cells in HIV Infection [INFECTIOUS DISEASE AND HOST RESPONSE]

    Key Points

  • CMV coinfection promotes the generation of CD57+ CD4 Tmem in PLWH.

  • CD2/LFA-3 costimulation enhances the functionality of CD57+ CD4 Tmem.

  • IL-15 and TNF enhance chemoattraction of CD57+ CD4 Tmem to CX3CL1+ endothelial cells.




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    Molecular Drivers of Lymphocyte Organization in Vertebrate Mucosal Surfaces: Revisiting the TNF Superfamily Hypothesis [IMMUNOGENETICS]

    Key Points

  • Lymphotoxin axis is not essential for formation of O-MALT in ectotherms and birds.

  • Vertebrate O-MALT structures are enriched in neuroactive ligand/receptor genes.

  • Mammalian PPs and LNs are enriched in genes involved in olfactory transduction.




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    Innate-like CD27+CD45RBhigh {gamma}{delta} T Cells Require TCR Signaling for Homeostasis in Peripheral Lymphoid Organs [IMMUNE SYSTEM DEVELOPMENT]

    Key Points

  • E4 is an enhancer element that regulates transcriptions of TCR genes.

  • E4–/– mice have fewer CD27+CD45RBhigh V2+ T cells in peripheral organs.

  • Attenuation of TCR signal impairs homeostasis of T cells in peripheral organs.




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    Complement Deficiencies Result in Surrogate Pathways of Complement Activation in Novel Polygenic Lupus-like Models of Kidney Injury [AUTOIMMUNITY]

    Key Points

  • Novel TM lupus mouse strains develop spontaneous nephritis.

  • In C1q deficiency, kidney complement activation likely occurred via the LP.

  • In C3 deficiency, coagulation cascade contributed to kidney complement activation.




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    The Factor H-Binding Site of CspZ as a Protective Target against Multistrain, Tick-Transmitted Lyme Disease [Microbial Immunity and Vaccines]

    The spirochete Borrelia burgdorferi sensu lato is the causative agent of Lyme disease (LD). The spirochetes produce the CspZ protein that binds to a complement regulator, factor H (FH). Such binding downregulates activation of host complement to facilitate spirochete evasion of complement killing. However, vaccination with CspZ does not protect against LD infection. In this study, we demonstrated that immunization with CspZ-YA, a CspZ mutant protein with no FH-binding activity, protected mice from infection by several spirochete genotypes introduced via tick feeding. We found that the sera from CspZ-YA-vaccinated mice more efficiently eliminated spirochetes and blocked CspZ FH-binding activity than sera from CspZ-immunized mice. We also found that vaccination with CspZ, but not CspZ-YA, triggered the production of anti-FH antibodies, justifying CspZ-YA as an LD vaccine candidate. The mechanistic and efficacy information derived from this study provides insights into the development of a CspZ-based LD vaccine.




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    Immune Profile of the Nasal Mucosa in Patients with Cutaneous Leishmaniasis [Fungal and Parasitic Infections]

    Localized skin lesions are characteristic of cutaneous leishmaniasis (CL); however, Leishmania (Viannia) species, which are responsible for most CL cases in the Americas, can spread systemically, sometimes resulting in mucosal disease. Detection of Leishmania has been documented in healthy mucosal tissues (conjunctiva, tonsils, and nasal mucosa) and healthy skin of CL patients and in individuals with asymptomatic infection in areas of endemicity of L. (V.) panamensis and L. (V.) braziliensis transmission. However, the conditions and mechanisms that favor parasite persistence in healthy mucosal tissues are unknown. In this descriptive study, we compared the cell populations of the nasal mucosa (NM) of healthy donors and patients with active CL and explored the immune gene expression signatures related to molecular detection of Leishmania in this tissue in the absence of clinical signs or symptoms of mucosal disease. The cellular composition and gene expression profiles of NM samples from active CL patients were similar to those of healthy volunteers, with a predominance of epithelial over immune cells, and within the CD45+ cell population, a higher frequency of CD66b+ followed by CD14+ and CD3+ cells. In CL patients with molecular evidence of Leishmania persistence in the NM, genes characteristic of an anti-inflammatory and tissue repair responses (IL4R, IL5RA, POSTN, and SATB1) were overexpressed relative to NM samples from CL patients in which Leishmania was not detected. Here, we report the first immunological description of subclinically infected NM tissues of CL patients and provide evidence of a local anti-inflammatory environment favoring parasite persistence in the NM.




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    GABARAPL2 Is Critical for Growth Restriction of Toxoplasma gondii in HeLa Cells Treated with Gamma Interferon [Cellular Microbiology: Pathogen-Host Cell Molecular Interactions]

    Gamma interferon (IFN-)-induced innate immune responses play important roles in the inhibition of Toxoplasma gondii infection. It has been reported that IFN- stimulates non-acidification-dependent growth restriction of T. gondii in HeLa cells, but the mechanism remains unclear. Here, we found that -aminobutyric acid (GABA) receptor-associated protein-like 2 (GABARAPL2) plays a critical role in parasite restriction in IFN--treated HeLa cells. GABARAPL2 is recruited to membrane structures surrounding parasitophorous vacuoles (PV). Autophagy adaptors are required for the proper localization and function of GABARAPL2 in the IFN- -induced immune response. These findings provide further understanding of a noncanonical autophagy pathway responsible for IFN--dependent inhibition of T. gondii growth in human HeLa cells and demonstrate the critical role of GABARAPL2 in this response.




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    Differential Response of the Chicken Trachea to Chronic Infection with Virulent Mycoplasma gallisepticum Strain Ap3AS and Vaxsafe MG (Strain ts-304): a Transcriptional Profile [Host Response and Inflammation]

    Mycoplasma gallisepticum is the primary etiological agent of chronic respiratory disease in chickens. Live attenuated vaccines are most commonly used in the field to control the disease, but current vaccines have some limitations. Vaxsafe MG (strain ts-304) is a new vaccine candidate that is efficacious at a lower dose than the current commercial vaccine strain ts-11, from which it is derived. In this study, the transcriptional profiles of the trachea of unvaccinated chickens and chickens vaccinated with strain ts-304 were compared 2 weeks after challenge with M. gallisepticum strain Ap3AS during the chronic stage of infection. After challenge, genes, gene ontologies, pathways, and protein classes involved in inflammation, cytokine production and signaling, and cell proliferation were upregulated, while those involved in formation and motor movement of cilia, formation of intercellular junctional complexes, and formation of the cytoskeleton were downregulated in the unvaccinated birds compared to the vaccinated birds, reflecting immune dysregulation and the pathological changes induced in the trachea by infection with M. gallisepticum. Vaccination appears to protect the structural and functional integrity of the tracheal mucosa 2 weeks after infection with M. gallisepticum.




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    Porphyromonas gingivalis Cell Wall Components Induce Programmed Death Ligand 1 (PD-L1) Expression on Human Oral Carcinoma Cells by a Receptor-Interacting Protein Kinase 2 (RIP2)-Dependent Mechanism [Cellular Microbiology: Pathogen-Host Cell Molecular Inte

    Programmed death-ligand 1 (PD-L1/B7-H1) serves as a cosignaling molecule in cell-mediated immune responses and contributes to chronicity of inflammation and the escape of tumor cells from immunosurveillance. Here, we investigated the molecular mechanisms leading to PD-L1 upregulation in human oral carcinoma cells and in primary human gingival keratinocytes in response to infection with Porphyromonas gingivalis (P. gingivalis), a keystone pathogen for the development of periodontitis. The bacterial cell wall component peptidoglycan uses bacterial outer membrane vesicles to be taken up by cells. Internalized peptidoglycan triggers cytosolic receptors to induce PD-L1 expression in a myeloid differentiation primary response 88 (Myd88)-independent and receptor-interacting serine/threonine-protein kinase 2 (RIP2)-dependent fashion. Interference with the kinase activity of RIP2 or mitogen-activated protein (MAP) kinases interferes with inducible PD-L1 expression.




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    Heterogeneous Nuclear Ribonucleoprotein L Negatively Regulates Foot-and-Mouth Disease Virus Replication through Inhibition of Viral RNA Synthesis by Interacting with the Internal Ribosome Entry Site in the 5' Untranslated Region [Virus-Cell Interactio

    Upon infection, the highly structured 5' untranslated region (5' UTR) of picornavirus is involved in viral protein translation and RNA synthesis. As a critical element in the 5' UTR, the internal ribosome entry site (IRES) binds to various cellular proteins to function in the processes of picornavirus replication. Foot-and-mouth disease virus (FMDV) is an important member in the family Picornaviridae, and its 5' UTR contains a functional IRES element. In this study, the cellular heterogeneous nuclear ribonucleoprotein L (hnRNP L) was identified as an IRES-binding protein for FMDV by biotinylated RNA pulldown assays, mass spectrometry (MS) analysis, and determination of hnRNP L-IRES interaction regions. Further, we found that hnRNP L inhibited the growth of FMDV through binding to the viral IRES and that the inhibitory effect of hnRNP L on FMDV growth was not due to FMDV IRES-mediated translation, but to influence on viral RNA synthesis. Finally, hnRNP L was demonstrated to coimmunoprecipitate with RNA-dependent RNA polymerase (3Dpol) in an FMDV RNA-dependent manner in the infected cells. Thus, our results suggest that hnRNP L, as a critical IRES-binding protein, negatively regulates FMDV replication by inhibiting viral RNA synthesis, possibly by remaining in the replication complex.

    IMPORTANCE Picornaviruses, as a large family of human and animal pathogens, cause a bewildering array of disease syndromes. Many host factors are implicated in the pathogenesis of these viruses, and some proteins interact with the viral IRES elements to affect function. Here, we report for the first time that cellular hnRNP L specifically interacts with the IRES of the picornavirus FMDV and negatively regulates FMDV replication through inhibiting viral RNA synthesis. Further, our results showed that hnRNP L coimmunoprecipitates with FMDV 3Dpol in a viral RNA-dependent manner, suggesting that it may remain in the replication complex to function. The data presented here would facilitate further understanding of virus-host interactions and the pathogenesis of picornavirus infections.




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    Procedural justice training reduces police use of force and complaints against officers [Social Sciences]

    Existing research shows that distrust of the police is widespread and consequential for public safety. However, there is a shortage of interventions that demonstrably reduce negative police interactions with the communities they serve. A training program in Chicago attempted to encourage 8,480 officers to adopt procedural justice policing strategies. These...




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    Asking young children to &#x201C;do science&#x201D; instead of &#x201C;be scientists&#x201D; increases science engagement in a randomized field experiment [Psychological and Cognitive Sciences]

    Subtle features of common language can imply to young children that scientists are a special and distinct kind of person—a way of thinking that can interfere with the development of children’s own engagement with science. We conducted a large field experiment (involving 45 prekindergarten schools, 130 teachers, and over 1,100...




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    Single-cell O2 exchange imaging shows that cytoplasmic diffusion is a dominant barrier to efficient gas transport in red blood cells [Physiology]

    Disorders of oxygen transport are commonly attributed to inadequate carrying capacity (anemia) but may also relate to inefficient gas exchange by red blood cells (RBCs), a process that is poorly characterized yet assumed to be rapid. Without direct measurements of gas exchange at the single-cell level, the barriers to O2...




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    Reversal of hyperactive subthalamic circuits differentially mitigates pain hypersensitivity phenotypes in parkinsonian mice [Neuroscience]

    Although pain is a prevalent nonmotor symptom in Parkinson’s disease (PD), it is undertreated, in part because of our limited understanding of the underlying mechanisms. Considering that the basal ganglia are implicated in pain sensation, and that their synaptic outputs are controlled by the subthalamic nucleus (STN), we hypothesized that...




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    Transposon mobilization in the human fungal pathogen Cryptococcus is mutagenic during infection and promotes drug resistance in vitro [Microbiology]

    When transitioning from the environment, pathogenic microorganisms must adapt rapidly to survive in hostile host conditions. This is especially true for environmental fungi that cause opportunistic infections in immunocompromised patients since these microbes are not well adapted human pathogens. Cryptococcus species are yeastlike fungi that cause lethal infections, especially in...




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    Landscape analysis of ad&#x0237;acent gene rearrangements reveals BCL2L14-ETV6 gene fusions in more aggressive triple-negative breast cancer [Genetics]

    Triple-negative breast cancer (TNBC) accounts for 10 to 20% of breast cancer, with chemotherapy as its mainstay of treatment due to lack of well-defined targets, and recent genomic sequencing studies have revealed a paucity of TNBC-specific mutations. Recurrent gene fusions comprise a class of viable genetic targets in solid tumors;...




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    Improved surrogates in inertial confinement fusion with manifold and cycle consistencies [Computer Sciences]

    Neural networks have become the method of choice in surrogate modeling because of their ability to characterize arbitrary, high-dimensional functions in a data-driven fashion. This paper advocates for the training of surrogates that are 1) consistent with the physical manifold, resulting in physically meaningful predictions, and 2) cyclically consistent with...




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    Cryo-EM structure of C9ORF72-SMCR8-WDR41 reveals the role as a GAP for Rab8a and Rab11a [Biochemistry]

    A massive intronic hexanucleotide repeat (GGGGCC) expansion in C9ORF72 is a genetic origin of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Recently, C9ORF72, together with SMCR8 and WDR41, has been shown to regulate autophagy and function as Rab GEF. However, the precise function of C9ORF72 remains unclear. Here, we...




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    Moderation of mitochondrial respiration mitigates metabolic syndrome of aging [Biochemistry]

    Deregulation of mitochondrial dynamics leads to the accumulation of oxidative stress and unhealthy mitochondria; consequently, this accumulation contributes to premature aging and alterations in mitochondria linked to metabolic complications. We postulate that restrained mitochondrial ATP synthesis might alleviate age-associated disorders and extend healthspan in mammals. Herein, we prepared a previously...




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    Emergence of self-organized multivortex states in flocks of active rollers [Applied Physical Sciences]

    Active matter, both synthetic and biological, demonstrates complex spatiotemporal self-organization and the emergence of collective behavior. A coherent rotational motion, the vortex phase, is of great interest because of its ability to orchestrate well-organized motion of self-propelled particles over large distances. However, its generation without geometrical confinement has been a...




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    Bringing light to ER contacts and a new phase in organelle communication [Cell Biology]

    Functioning cells depend on the outward-facing plasma membrane (PM) effectively contacting the endoplasmic reticulum (ER), which serves as a central hub for contacts with mitochondria and other intracellular organelles. The contact sites are critical to intracellular communication because they mediate intermembrane exchange of lipids, ions, and other small molecules that...




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    Closing the gap between mind and brain with the dynamic connectome [Neuroscience]

    At the pinnacle of the 17th century scientific revolution, René Descartes, the father of modern philosophy, published his monumental Meditations on First Philosophy (1), in which he proposed a division between soul and body—mind and brain—with the former in charge of our thoughts and conscious decisions (res cogitans) and the...




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    Lowering Gestational Diabetes Risk by Prenatal Weight Gain Counseling

    Purpose:

    Excess weight gain during pregnancy is at epidemic proportions, and pregnancy complications are also on the rise. We sought to determine whether better weight gain counseling of expectant mothers will improve obstetric outcomes.

    Methods:

    Our historic control study design included 2 years of preintervention data, then 6 months of physician and staff training in prenatal weight gain counseling in accordance with 2009 Institute of Medicine guidelines, and finally, 2 more years of data collection for postintervention outcomes. Seven family medicine residency clinics monitored 1571 continuity prenatal cases. Counseling recommendations were noted and the following outcomes were analyzed: gestational age, birth weight, route of delivery, and the incidences of hypertension and gestational diabetes. Multiple logistic regression was used to control for demographic variables and body mass index at enrollment.

    Results:

    Institute of Medicine congruent counseling increased from 10% to 63% (P < .01). Excess weight gain decreased from 46.4% to 41.5% (adjusted odds ratio [AOR] = 0.85; 95% CI, 0.63–1.16; P = .10). Gestational diabetes decreased significantly from 11.5% to 7.3% (P = .008). The difference remained statistically significant even after adjusting for prepregnancy obesity and other clinical and demographic characteristics (AOR = 0.54; 95% CI, 0.32–0.91; P = .02). Differences in gestational age, birth weight, hypertension, primary cesarean, and shoulder dystocia were not statistically significant.

    Conclusions:

    Improved weight gain counseling of prenatal patients by physicians did reduce the pregnancy complication of gestational diabetes. This occurred even though the trend toward less excess weight gain was not statistically significant.




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    Svalbard ptarmigans don't prioritise fighting infection in winter [INSIDE JEB]

    Kathryn Knight