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1.
Nature ; 615(7952): 472-481, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36859544

RESUMEN

The meninges are densely innervated by nociceptive sensory neurons that mediate pain and headache1,2. Bacterial meningitis causes life-threatening infections of the meninges and central nervous system, affecting more than 2.5 million people a year3-5. How pain and neuroimmune interactions impact meningeal antibacterial host defences are unclear. Here we show that Nav1.8+ nociceptors signal to immune cells in the meninges through the neuropeptide calcitonin gene-related peptide (CGRP) during infection. This neuroimmune axis inhibits host defences and exacerbates bacterial meningitis. Nociceptor neuron ablation reduced meningeal and brain invasion by two bacterial pathogens: Streptococcus pneumoniae and Streptococcus agalactiae. S. pneumoniae activated nociceptors through its pore-forming toxin pneumolysin to release CGRP from nerve terminals. CGRP acted through receptor activity modifying protein 1 (RAMP1) on meningeal macrophages to polarize their transcriptional responses, suppressing macrophage chemokine expression, neutrophil recruitment and dural antimicrobial defences. Macrophage-specific RAMP1 deficiency or pharmacological blockade of RAMP1 enhanced immune responses and bacterial clearance in the meninges and brain. Therefore, bacteria hijack CGRP-RAMP1 signalling in meningeal macrophages to facilitate brain invasion. Targeting this neuroimmune axis in the meninges can enhance host defences and potentially produce treatments for bacterial meningitis.


Asunto(s)
Encéfalo , Meninges , Meningitis Bacterianas , Neuroinmunomodulación , Humanos , Encéfalo/inmunología , Encéfalo/microbiología , Péptido Relacionado con Gen de Calcitonina/metabolismo , Meninges/inmunología , Meninges/microbiología , Meninges/fisiopatología , Dolor/etiología , Canal de Sodio Activado por Voltaje NAV1.8/metabolismo , Meningitis Bacterianas/complicaciones , Meningitis Bacterianas/inmunología , Meningitis Bacterianas/microbiología , Meningitis Bacterianas/patología , Streptococcus agalactiae/inmunología , Streptococcus agalactiae/patogenicidad , Streptococcus pneumoniae/inmunología , Streptococcus pneumoniae/patogenicidad , Nociceptores/metabolismo , Proteína 1 Modificadora de la Actividad de Receptores/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo
2.
Cell ; 152(1-2): 340-51, 2013 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-23332765

RESUMEN

Monitoring cancer and aging in vivo remains experimentally challenging. Here, we describe a luciferase knockin mouse (p16(LUC)), which faithfully reports expression of p16(INK4a), a tumor suppressor and aging biomarker. Lifelong assessment of luminescence in p16(+/LUC) mice revealed an exponential increase with aging, which was highly variable in a cohort of contemporaneously housed, syngeneic mice. Expression of p16(INK4a) with aging did not predict cancer development, suggesting that the accumulation of senescent cells is not a principal determinant of cancer-related death. In 14 of 14 tested tumor models, expression of p16(LUC) was focally activated by early neoplastic events, enabling visualization of tumors with sensitivity exceeding other imaging modalities. Activation of p16(INK4a) was noted in the emerging neoplasm and surrounding stromal cells. This work suggests that p16(INK4a) activation is a characteristic of all emerging cancers, making the p16(LUC) allele a sensitive, unbiased reporter of neoplastic transformation.


Asunto(s)
Envejecimiento/genética , Biomarcadores , Transformación Celular Neoplásica , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Luciferasas/genética , Neoplasias/genética , Animales , Senescencia Celular , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Femenino , Técnicas de Sustitución del Gen , Ratones , Neoplasias/fisiopatología , Heridas y Lesiones/genética
3.
EMBO J ; 42(14): e112693, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37259639

RESUMEN

Infection directly influences adult hematopoietic stem cell (HSC) function and differentiation, but the fetal hematopoietic response to infection during pregnancy is not well-studied. Here, we investigated the fetal hematopoietic response to maternal infection with Toxoplasma gondii (T. gondii), an intracellular parasite that elicits Type II IFNγ-mediated maternal immunity. While it is known that maternal infection without direct pathogen transmission can affect fetal immune development, the effects of maternal IFNγ on developing HSCs and the signals that mediate these interactions have not been investigated. Our investigation reveals that the fetal HSCs respond to T. gondii infection with virulence-dependent changes in proliferation, self-renewal potential, and lineage output. Furthermore, maternal IFNγ crosses the fetal-maternal interface, where it is perceived by fetal HSCs. By comparing the effects of maternal IFNγ injection with maternal T. gondii infection, we reveal that the effects of IFNγ treatment mimic some aspects of the fetal HSC response to infection. Moreover, our findings illuminate that the fetal HSC response to prenatal infection is distinct from the adult HSC response to IFNγ-induced inflammation. Altogether, our data disentangle the role of infection-induced inflammatory cytokines in driving the expansion of downstream hematopoietic progenitors.


Asunto(s)
Toxoplasma , Toxoplasmosis , Embarazo , Femenino , Humanos , Células Madre Hematopoyéticas , Diferenciación Celular , Toxoplasmosis/metabolismo , Inflamación
4.
Mol Cell ; 73(6): 1174-1190.e12, 2019 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-30745086

RESUMEN

Chromatin loops enable transcription-factor-bound distal enhancers to interact with their target promoters to regulate transcriptional programs. Although developmental transcription factors such as active forms of Notch can directly stimulate transcription by activating enhancers, the effect of their oncogenic subversion on the 3D organization of cancer genomes is largely undetermined. By mapping chromatin looping genome-wide in Notch-dependent triple-negative breast cancer and B cell lymphoma, we show that beyond the well-characterized role of Notch as an activator of distal enhancers, Notch regulates its direct target genes by instructing enhancer repositioning. Moreover, a large fraction of Notch-instructed regulatory loops form highly interacting enhancer and promoter spatial clusters termed "3D cliques." Loss- and gain-of-function experiments show that Notch preferentially targets hyperconnected 3D cliques that regulate the expression of crucial proto-oncogenes. Our observations suggest that oncogenic hijacking of developmental transcription factors can dysregulate transcription through widespread effects on the spatial organization of cancer genomes.


Asunto(s)
Transformación Celular Neoplásica/genética , Cromatina/genética , Linfoma de Células B/genética , Oncogenes , Receptores Notch/genética , Neoplasias de la Mama Triple Negativas/genética , Sitios de Unión , Linaje de la Célula/genética , Proliferación Celular/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Cromatina/metabolismo , Ensamble y Desensamble de Cromatina , Ciclina D1/genética , Ciclina D1/metabolismo , Elementos de Facilitación Genéticos , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Células HEK293 , Humanos , Linfoma de Células B/metabolismo , Linfoma de Células B/patología , Mutación , Conformación de Ácido Nucleico , Regiones Promotoras Genéticas , Unión Proteica , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Receptores Notch/metabolismo , Transducción de Señal/genética , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología
5.
Nat Chem Biol ; 20(6): 779-788, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38355721

RESUMEN

The retinal light response in animals originates from the photoisomerization of an opsin-coupled 11-cis-retinaldehyde chromophore. This visual chromophore is enzymatically produced through the action of carotenoid cleavage dioxygenases. Vertebrates require two carotenoid cleavage dioxygenases, ß-carotene oxygenase 1 and retinal pigment epithelium 65 (RPE65), to form 11-cis-retinaldehyde from carotenoid substrates, whereas invertebrates such as insects use a single enzyme known as Neither Inactivation Nor Afterpotential B (NinaB). RPE65 and NinaB couple trans-cis isomerization with hydrolysis and oxygenation, respectively, but the mechanistic relationship of their isomerase activities remains unknown. Here we report the structure of NinaB, revealing details of its active site architecture and mode of membrane binding. Structure-guided mutagenesis studies identify a residue cluster deep within the NinaB substrate-binding cleft that controls its isomerization activity. Our data demonstrate that isomerization activity is mediated by distinct active site regions in NinaB and RPE65-an evolutionary convergence that deepens our understanding of visual system diversity.


Asunto(s)
Carotenoides , Carotenoides/metabolismo , Carotenoides/química , Animales , Dominio Catalítico , Retinaldehído/metabolismo , Retinaldehído/química , cis-trans-Isomerasas/metabolismo , cis-trans-Isomerasas/genética , cis-trans-Isomerasas/química , Dioxigenasas/metabolismo , Dioxigenasas/química , Dioxigenasas/genética , Humanos , Modelos Moleculares , Evolución Molecular
6.
J Biol Chem ; 300(6): 107352, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723750

RESUMEN

In Escherichia coli, the master transcription regulator catabolite repressor activator (Cra) regulates >100 genes in central metabolism. Cra binding to DNA is allosterically regulated by binding to fructose-1-phosphate (F-1-P), but the only documented source of F-1-P is from the concurrent import and phosphorylation of exogenous fructose. Thus, many have proposed that fructose-1,6-bisphosphate (F-1,6-BP) is also a physiological regulatory ligand. However, the role of F-1,6-BP has been widely debated. Here, we report that the E. coli enzyme fructose-1-kinase (FruK) can carry out its "reverse" reaction under physiological substrate concentrations to generate F-1-P from F-1,6-BP. We further show that FruK directly binds Cra with nanomolar affinity and forms higher order, heterocomplexes. Growth assays with a ΔfruK strain and fruK complementation show that FruK has a broader role in metabolism than fructose catabolism. Since fruK itself is repressed by Cra, these newly-reported events add layers to the dynamic regulation of E. coli's central metabolism that occur in response to changing nutrients. These findings might have wide-spread relevance to other γ-proteobacteria, which conserve both Cra and FruK.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Fructoquinasas/metabolismo , Fructoquinasas/genética , Fructosa/metabolismo , Fructosadifosfatos/metabolismo , Fructosafosfatos/metabolismo , Regulación Bacteriana de la Expresión Génica
7.
EMBO J ; 40(7): e106103, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33522633

RESUMEN

Streptococcus agalactiae, also known as group B Streptococcus (GBS), is the major cause of neonatal sepsis in humans. A critical step to infection is adhesion of bacteria to epithelial surfaces. GBS adhesins have been identified to bind extracellular matrix components and cellular receptors. However, several putative adhesins have no host binding partner characterised. We report here that surface-expressed ß protein of GBS binds to human CEACAM1 and CEACAM5 receptors. A crystal structure of the complex showed that an IgSF domain in ß represents a novel Ig-fold subtype called IgI3, in which unique features allow binding to CEACAM1. Bioinformatic assessment revealed that this newly identified IgI3 fold is not exclusively present in GBS but is predicted to be present in adhesins from other clinically important human pathogens. In agreement with this prediction, we found that CEACAM1 binds to an IgI3 domain found in an adhesin from a different streptococcal species. Overall, our results indicate that the IgI3 fold could provide a broadly applied mechanism for bacteria to target CEACAMs.


Asunto(s)
Adhesinas Bacterianas/química , Antígenos CD/química , Antígeno Carcinoembrionario/química , Moléculas de Adhesión Celular/química , Adhesinas Bacterianas/metabolismo , Animales , Antígenos CD/metabolismo , Sitios de Unión , Células CHO , Antígeno Carcinoembrionario/metabolismo , Moléculas de Adhesión Celular/metabolismo , Cricetinae , Cricetulus , Proteínas Ligadas a GPI/química , Proteínas Ligadas a GPI/metabolismo , Células HeLa , Humanos , Unión Proteica , Streptococcus agalactiae/metabolismo
8.
Blood ; 142(19): 1647-1657, 2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37441846

RESUMEN

Mutations in splicing factor (SF) genes SRSF2, U2AF1, SF3B1, and ZRSR2 are now considered adverse risk in the European LeukemiaNet 2022 acute myeloid leukemia (AML) risk stratification. The prognostic impact of SF mutations in AML has been predominantly derived from younger patients treated with intensive (INT) therapy. We evaluated 994 patients with newly diagnosed AML, including 266 (27%) with a SFmut. Median age was 67 years overall, with patients with SFmut being older at 72 years. SRSF2 (n = 140, 53%) was the most common SFmut. In patients treated with INT, median relapse-free survival (RFS) (9.6 vs 21.4 months, P = .04) and overall survival (OS) (15.9 vs 26.7 months, P = .06) were shorter for patients with SFmut than without SFwt, however this significance abrogated when evaluating patients who received venetoclax with INT therapy (RFS 15.4 vs 20.3 months, P = .36; OS 19.6 vs 30.7 months, P = .98). In patients treated with LI, median RFS (9.3 vs 7.7 months, P = .35) and OS (12.3 vs 8.5 months, P = .14) were similar for patients with and without SFmut , and outcomes improved in all groups with venetoclax. On multivariate analysis, SFmut did not affect hazards of relapse and death for INT arm but reduced both these hazards in LI arm. In a large AML data set with >60% of patients receiving venetoclax with LI/INT therapy, SFmut had no independent negative prognostic impact. Newer prognostic models that consider LI therapy and use of venetoclax among other factors are warranted.


Asunto(s)
Leucemia Mieloide Aguda , Humanos , Anciano , Factores de Empalme de ARN/genética , Pronóstico , Factores de Empalme Serina-Arginina/genética , Factor de Empalme U2AF/genética , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Mutación
9.
PLoS Biol ; 20(2): e3001555, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35180210

RESUMEN

Bacterial membrane lipids are critical for membrane bilayer formation, cell division, protein localization, stress responses, and pathogenesis. Despite their critical roles, membrane lipids have not been fully elucidated for many pathogens. Here, we report the discovery of a novel cationic glycolipid, lysyl-glucosyl-diacylglycerol (Lys-Glc-DAG), which is synthesized in high abundance by the bacterium Streptococcus agalactiae (Group B Streptococcus, GBS). To our knowledge, Lys-Glc-DAG is more positively charged than any other known lipids. Lys-Glc-DAG carries 2 positive net charges per molecule, distinct from the widely described lysylated phospholipid lysyl-phosphatidylglycerol (Lys-PG) that carries one positive net charge due to the presence of a negatively charged phosphate moiety. We use normal phase liquid chromatography (NPLC) coupled with electrospray ionization (ESI) high-resolution tandem mass spectrometry (HRMS/MS) and genetic approaches to determine that Lys-Glc-DAG is synthesized by the enzyme MprF in GBS, which covalently modifies the neutral glycolipid Glc-DAG with the cationic amino acid lysine. GBS is a leading cause of neonatal meningitis, which requires traversal of the endothelial blood-brain barrier (BBB). We demonstrate that GBS strains lacking mprF exhibit a significant decrease in the ability to invade BBB endothelial cells. Further, mice challenged with a GBSΔmprF mutant developed bacteremia comparably to wild-type (WT) infected mice yet had less recovered bacteria from brain tissue and a lower incidence of meningitis. Thus, our data suggest that Lys-Glc-DAG may contribute to bacterial uptake into host cells and disease progression. Importantly, our discovery provides a platform for further study of cationic lipids at the host-pathogen interface.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Glucolípidos/metabolismo , Meningitis/metabolismo , Streptococcus agalactiae/metabolismo , Aminoaciltransferasas/genética , Aminoaciltransferasas/metabolismo , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Transporte Biológico/genética , Cationes/química , Cromatografía Liquida/métodos , Glucolípidos/química , Humanos , Masculino , Ratones , Mutación , Espectrometría de Masa por Ionización de Electrospray/métodos , Streptococcus agalactiae/genética , Espectrometría de Masas en Tándem/métodos
10.
Mol Microbiol ; 120(2): 258-275, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37357823

RESUMEN

Type VIIb secretion systems (T7SSb) in Gram-positive bacteria facilitate physiology, interbacterial competition, and/or virulence via EssC ATPase-driven secretion of small ɑ-helical proteins and toxins. Recently, we characterized T7SSb in group B Streptococcus (GBS), a leading cause of infection in newborns and immunocompromised adults. GBS T7SS comprises four subtypes based on variation in the C-terminus of EssC and the repertoire of downstream effectors; however, the intraspecies diversity of GBS T7SS and impact on GBS-host interactions remains unknown. Bioinformatic analysis indicates that GBS T7SS loci encode subtype-specific putative effectors, which have low interspecies and inter-subtype homology but contain similar domains/motifs and therefore may serve similar functions. We further identify orphaned GBS WXG100 proteins. Functionally, we show that GBS T7SS subtype I and III strains secrete EsxA in vitro and that in subtype I strain CJB111, esxA1 appears to be differentially transcribed from the T7SS operon. Furthermore, we observe subtype-specific effects of GBS T7SS on host colonization, as CJB111 subtype I but not CNCTC 10/84 subtype III T7SS promotes GBS vaginal colonization. Finally, we observe that T7SS subtypes I and II are the predominant subtypes in clinical GBS isolates. This study highlights the potential impact of T7SS heterogeneity on host-GBS interactions.


Asunto(s)
Infecciones Estreptocócicas , Sistemas de Secreción Tipo VII , Recién Nacido , Femenino , Humanos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sistemas de Secreción Tipo VII/genética , Virulencia , Operón/genética , Genitales Femeninos/metabolismo , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/genética , Streptococcus agalactiae/metabolismo , Vagina/metabolismo , Vagina/microbiología
11.
Cancer ; 130(20): 3452-3462, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38896064

RESUMEN

INTRODUCTION: NPM1-mutated (NPM1mut) myeloid neoplasms (MNs) with <20% bone marrow (BM) blasts (NPM1mut MNs<20) are uncommon, and their classification remains inconsistent. METHODS: The clinicopathologic features of 54 patients with NPM1mut MNs <20 were evaluated and compared with wild-type NPM1 MNs <20 and NPM1mut MNs≥20, respectively. RESULTS: NPM1mut MNs had similar features regardless of blast percentage, except for higher IDH2 (29% vs 7%, p = .023) and FLT3 (70% vs 11%, p < .001) frequency in patients with ≥20% BM blasts. Thirty-three (61%) patients with NPM1mut MNs <20 received low-intensity chemotherapy (LIC) and 12 (22%) received intensive chemotherapy (IC). Higher complete remission rates (75% vs 27%, p = .006) and median overall survival (mOS) (not reached vs 30.4 months, p = .06) were observed with IC compared to LIC. Young patients (age <60 years) did not reach mOS either when treated with LIC or IC. Stem cell transplant was associated with increased survival only in patients treated with LIC (HR, 0.24; p = .025). No differences in mOS were observed by BM blast strata (32.2 months, not reached and 46.9 months for <10%, 10%-19%, and ≥20% blasts, p = .700) regardless of treatment modality (LIC: p = .900; IC: p = .360). Twenty-three patients (43%) with NPM1mut MNs <20 had marrow blast progression to ≥20%. CONCLUSIONS: Overall, NPM1mut MNs define a unique entity independent of BM blast percentage.


Asunto(s)
Mutación , Proteínas Nucleares , Nucleofosmina , Humanos , Masculino , Persona de Mediana Edad , Proteínas Nucleares/genética , Femenino , Anciano , Adulto , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/patología , Trastornos Mieloproliferativos/tratamiento farmacológico , Médula Ósea/patología , Adulto Joven , Anciano de 80 o más Años , Tirosina Quinasa 3 Similar a fms/genética , Pronóstico
12.
J Virol ; 97(4): e0007323, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37022165

RESUMEN

Stress-mediated activation of the glucocorticoid receptor (GR) and specific stress-induced transcription factors stimulate herpes simplex virus 1 (HSV-1) productive infection, explant-induced reactivation, and immediate early (IE) promoters that drive expression of infected cell protein 0 (ICP0), ICP4, and ICP27. Several published studies concluded the virion tegument protein VP16, ICP0, and/or ICP4 drives early steps of reactivation from latency. Notably, VP16 protein expression was induced in trigeminal ganglionic neurons of Swiss Webster or C57BL/6J mice during early stages of stress-induced reactivation. If VP16 mediates reactivation, we hypothesized stress-induced cellular transcription factors would stimulate its expression. To address this hypothesis, we tested whether stress-induced transcription factors transactivate a VP16 cis-regulatory module (CRM) located upstream of the VP16 TATA box (-249 to -30). Initial studies revealed the VP16 CRM cis-activated a minimal promoter more efficiently in mouse neuroblastoma cells (Neuro-2A) than mouse fibroblasts (NIH-3T3). GR and Slug, a stress-induced transcription factor that binds enhancer boxes (E-boxes), were the only stress-induced transcription factors examined that transactivated the VP16 CRM construct. GR- and Slug-mediated transactivation was reduced to basal levels when the E-box, two 1/2 GR response elements (GREs), or NF-κB binding site was mutated. Previous studies revealed GR and Slug cooperatively transactivated the ICP4 CRM, but not ICP0 or ICP27. Silencing of Slug expression in Neuro-2A cells significantly reduced viral replication, indicating Slug-mediated transactivation of ICP4 and VP16 CRM activity correlates with enhanced viral replication and reactivation from latency. IMPORTANCE Herpes simplex virus 1 (HSV-1) establishes lifelong latency in several types of neurons. Periodically cellular stressors trigger reactivation from latency. Viral regulatory proteins are not abundantly expressed during latency, indicating cellular transcription factors mediate early stages of reactivation. Notably, the glucocorticoid receptor (GR) and certain stress-induced transcription factors transactivate cis-regulatory modules (CRMs) essential for expression of infected cell protein 0 (ICP0) and ICP4, key viral transcriptional regulatory proteins linked to triggering reactivation from latency. Virion protein 16 (VP16) specifically transactivates IE promoter and was also reported to mediate early stages of reactivation from latency. GR and Slug, a stress-induced enhancer box (E-box) binding protein, transactivate a minimal promoter downstream of VP16 CRM, and these transcription factors occupy VP16 CRM sequences in transfected cells. Notably, Slug stimulates viral replication in mouse neuroblastoma cells suggesting Slug, by virtue of transactivating VP16 and ICP4 CRM sequences, can trigger reactivation in certain neurons.


Asunto(s)
Proteína Vmw65 de Virus del Herpes Simple , Herpesvirus Humano 1 , Regiones Promotoras Genéticas , Replicación Viral , Animales , Ratones , Regulación Viral de la Expresión Génica , Infecciones por Herpesviridae/virología , Herpesvirus Humano 1/fisiología , Ratones Endogámicos C57BL , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Replicación Viral/genética , Femenino , Proteína Vmw65 de Virus del Herpes Simple/genética , Proteína Vmw65 de Virus del Herpes Simple/metabolismo , Células 3T3 NIH , Latencia del Virus/genética , Mutación , ARN Interferente Pequeño/metabolismo
13.
J Virol ; 97(10): e0130523, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37823644

RESUMEN

IMPORTANCE: A correlation exists between stress and increased episodes of human alpha-herpes virus 1 reactivation from latency. Stress increases corticosteroid levels; consequently, the glucocorticoid receptor (GR) is activated. Recent studies concluded that a GR agonist, but not an antagonist, accelerates productive infection and reactivation from latency. Furthermore, GR and certain stress-induced transcription factors cooperatively transactivate promoters that drive the expression of infected cell protein 0 (ICP0), ICP4, and VP16. This study revealed female mice expressing a GR containing a serine to alanine mutation at position 229 (GRS229A) shed significantly lower levels of infectious virus during explant-induced reactivation compared to male GRS229A or wild-type parental C57BL/6 mice. Furthermore, female GRS229A mice contained fewer VP16 + TG neurons compared to male GRS229A mice or wild-type mice during the early stages of explant-induced reactivation from latency. Collectively, these studies revealed that GR transcriptional activity has female-specific effects, whereas male mice can compensate for the loss of GR transcriptional activation.


Asunto(s)
Herpes Simple , Herpesvirus Humano 1 , Receptores de Glucocorticoides , Activación Viral , Animales , Femenino , Masculino , Ratones , Herpes Simple/genética , Herpes Simple/virología , Herpesvirus Humano 1/fisiología , Proteínas Inmediatas-Precoces/metabolismo , Ratones Endogámicos C57BL , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Ganglio del Trigémino , Ubiquitina-Proteína Ligasas/metabolismo , Activación Viral/genética , Latencia del Virus/genética
14.
PLoS Pathog ; 18(3): e1010397, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35316308

RESUMEN

Bacterial infections are a major cause of morbidity and mortality worldwide and the rise of antibiotic resistance necessitates development of alternative treatments. Pathogen adhesins that bind to host cells initiate disease pathogenesis and represent potential therapeutic targets. We have shown previously that the BspC adhesin in Group B Streptococcus (GBS), the leading cause of bacterial neonatal meningitis, interacts with host vimentin to promote attachment to brain endothelium and disease development. Here we determined that the BspC variable (V-) domain contains the vimentin binding site and promotes GBS adherence to brain endothelium. Site directed mutagenesis identified a binding pocket necessary for GBS host cell interaction and development of meningitis. Using a virtual structure-based drug screen we identified compounds that targeted the V-domain binding pocket, which blocked GBS adherence and entry into the brain in vivo. These data indicate the utility of targeting the pathogen-host interface to develop anti-virulence therapeutics.


Asunto(s)
Meningitis Bacterianas , Infecciones Estreptocócicas , Adhesinas Bacterianas/genética , Adhesinas Bacterianas/metabolismo , Humanos , Recién Nacido , Meningitis Bacterianas/metabolismo , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae , Vimentina/metabolismo , Virulencia
15.
J Gen Intern Med ; 39(1): 36-44, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37550443

RESUMEN

BACKGROUND: Missed colonoscopy appointments delay screening and treatment for gastrointestinal disorders. Prior nonadherence with other care components may be associated with missed colonoscopy appointments. OBJECTIVE: To assess variability in prior adherence behaviors and their association with missed colonoscopy appointments. DESIGN: Retrospective cohort study. PARTICIPANTS: Patients scheduled for colonoscopy in an integrated healthcare system between January 2016 and December 2018. MAIN MEASURES: Prior adherence behaviors included: any missed outpatient appointment in the previous year; any missed gastroenterology clinic or colonoscopy appointment in the previous 2 years; and not obtaining a bowel preparation kit pre-colonoscopy. Other sociodemographic, clinical, and system characteristics were included in a multivariable model to identify independent associations between prior adherence behaviors and missed colonoscopy appointments. KEY RESULTS: The median age of the 57,590 participants was 61 years; 52.8% were female and 73.4% were white. Of 77,684 colonoscopy appointments, 3,237 (4.2%) were missed. Individuals who missed colonoscopy appointments were more likely to have missed a previous primary care appointment (62.5% vs. 38.4%), a prior gastroenterology appointment (18.4% vs. 4.7%) or not to have picked up a bowel preparation kit (42.4% vs. 17.2%), all p < 0.001. Correlations between the three adherence measures were weak (phi < 0.26). The rate of missed colonoscopy appointments increased from 1.8/100 among individuals who were adherent with all three prior care components to 24.6/100 among those who were nonadherent with all three care components. All adherence variables remained independently associated with nonadherence with colonoscopy in a multivariable model that included other covariates; adjusted odds ratios (with 95% confidence intervals) were 1.6 (1.5-1.8) for outpatient appointments, 1.9 (1.7-2.1) for gastroenterology appointments, and 3.1 (2.9-3.4) for adherence with bowel preparation kits, respectively. CONCLUSIONS: Three prior adherence behaviors were independently associated with missed colonoscopy appointments. Studies to predict adherence should use multiple, complementary measures of prior adherence when available.


Asunto(s)
Prestación Integrada de Atención de Salud , Cooperación del Paciente , Humanos , Femenino , Persona de Mediana Edad , Masculino , Estudios Retrospectivos , Colonoscopía , Citas y Horarios
16.
Transfusion ; 64(4): 693-704, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38511850

RESUMEN

BACKGROUND: Thousands of units of whole blood (WB) and blood components are transfused daily to treat trauma patients. Improved methods for blood storage are critical to support trauma-related care. The Hemanext ONE® system offers a unique method for hypoxic storage of WB, with successfully demonstrated storage of clinically viable RBCs. This work evaluated the system for the storage of WB, focusing on platelet health and function. STUDY DESIGN AND METHODS: WB was collected from healthy donors and processed through the Hemanext ONE® system. Hemoglobin oxygen saturation (HbSO2) levels of WB were depleted to 10%, 20%, or 30% of total HbSO2 and then stored in PVC bags sealed in oxygen-impermeable bags (except for normoxic control) with samples collected on days 1, 7, and 14 post-processing. Flow cytometry assessed the activation and apoptosis of platelets. Clot dynamics were assessed based on aggregometry and thromboelastography assays, as well as thrombin generation using a calibrated-automated thrombogram method. RESULTS: Hypoxic storage conditions were maintained throughout the storage period. Hypoxia triggered increased lactate production, but pH changes were negligible compared to normoxic control. Storage at 10% HbSO2 had a significant impact on platelet function, resulting in increased activation and reduced clot formation and aggregation. These effects were less significant at 20% and 30% HbSO2. DISCUSSION: This study indicates that platelets are sensitive to hypoxic storage and suffer significant metabolic and functional deterioration when stored at or below 10% HbSO2.


Asunto(s)
Plaquetas , Conservación de la Sangre , Humanos , Conservación de la Sangre/métodos , Plaquetas/metabolismo , Eritrocitos , Pruebas de Coagulación Sanguínea , Hipoxia
17.
J Exp Biol ; 227(2)2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-38099450

RESUMEN

Anthropogenic noise is becoming a major underwater pollutant because of rapidly increasing boat traffic worldwide. But its impact on aquatic organisms remains largely unknown. Previous studies have focused mainly on high-frequency and impulsive noises (i.e. sonar); however, boat noise is more pervasive, continuous, and its highest intensity and component frequencies overlap the auditory bandwidth of most fishes. We assessed the impacts of boat noise on saccular sensory hair cell density and hearing thresholds of a soniferous species, Atlantic croaker (Micropogonias undulatus). In two laboratory experiments, individuals were subjected to simulated boat noise: a single 15-min exposure and 3 days of intermittent noise (simulating passing vessels). Immediately after both experiments, fish were either (1) tested for hearing sensitivity with auditory evoked potential (AEP) tests or (2) euthanized for fluorescent phalloidin and TUNEL labeling for hair cell density counts. Relative to controls, no differences were observed in auditory thresholds nor hair cell density between individuals subjected to a single 15-min noise exposure. However, fish from the 3-day experiment showed decreased sensory hair cell density, increased apoptotic cells, and higher hearing thresholds than control fish at 300, 800 and 1000 Hz. Our results demonstrate that impacts from boat noise depend upon the duration and frequency of exposure. For a species reliant on vocalization for communication, these impacts may hinder spawning success, increase predation risks and significantly alter the ecosystem.


Asunto(s)
Perciformes , Navíos , Animales , Ecosistema , Audición , Perciformes/fisiología , Células Ciliadas Auditivas/fisiología , Peces/fisiología , Umbral Auditivo/fisiología
18.
Am J Obstet Gynecol ; 230(3): 370.e1-370.e12, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37741532

RESUMEN

BACKGROUND: In randomized trials, 1 primary outcome is typically chosen to evaluate the consequences of an intervention, whereas other important outcomes are relegated to secondary outcomes. This issue is amplified for many obstetrical trials in which an intervention may have consequences for both the pregnant person and the child. In contrast, desirability of outcome ranking, a paradigm shift for the design and analysis of clinical trials based on patient-centric evaluation, allows multiple outcomes-including from >1 individual-to be considered concurrently. OBJECTIVE: This study aimed to describe desirability of outcome ranking methodology tailored to obstetrical trials and to apply the methodology to maternal-perinatal paired (dyadic) outcomes in which both individuals may be affected by an intervention but may experience discordant outcomes (eg, an obstetrical intervention may improve perinatal but worsen maternal outcomes). STUDY DESIGN: This secondary analysis applies the desirability of outcome ranking methodology to data from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network ARRIVE trial. The original analysis found no substantial difference in the primary (perinatal composite) outcome, but a decreased risk of the secondary outcome of cesarean delivery with elective induction at 39 weeks. In the present desirability-of-outcome-ranking analysis, dyadic outcomes ranging from spontaneous vaginal delivery without severe neonatal complication (most desirable) to cesarean delivery with perinatal death (least desirable) were classified into 8 categories ranked by overall desirability by experienced investigators. Distributions of the desirability of outcome ranking were compared by estimating the probability of having a more desirable dyadic outcome with elective induction at 39 weeks of gestation than with expectant management. To account for various perspectives on these outcomes, a complementary analysis, called the partial credit strategy, was used to grade outcomes on a 100-point scale and estimate the difference in overall treatment scores between groups using a t test. RESULTS: All 6096 participants from the trial were included. The probability of a better dyadic outcome for a randomly selected patient who was randomized to elective induction was 53% (95% confidence interval, 51-54), implying that elective induction led to a better overall outcome for the dyad when taking multiple outcomes into account concurrently. Furthermore, the desirability-of-outcome-ranking probability of averting cesarean delivery with elective induction was 52% (95% confidence interval, 51-53), which was not at the expense of an operative vaginal delivery or a poorer outcome for the perinate (ie, survival with a severe neonatal complication or perinatal death). Randomization to elective induction was also advantageous in most of the partial credit score scenarios. CONCLUSION: Desirability-of-outcome-ranking methodology is a useful tool for obstetrical trials because it provides a concurrent view of the effect of an intervention on multiple dyadic outcomes, potentially allowing for better translation of data for decision-making and person-centered care.


Asunto(s)
Muerte Perinatal , Embarazo , Recién Nacido , Niño , Femenino , Humanos , Trabajo de Parto Inducido/métodos , Cesárea
19.
Am J Obstet Gynecol ; 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39288828

RESUMEN

BACKGROUND: The Chronic Hypertension and Pregnancy Study demonstrated that a target blood pressure of <140/90 mm Hg during pregnancy is associated with improved perinatal outcomes. Outside of pregnancy, pharmacologic therapy for patients with diabetes and hypertension is adjusted to a target blood pressure of <130/80 mm Hg. During pregnancy, patients with both diabetes and chronic hypertension may also benefit from tighter control with a target blood pressure <130/80 mm Hg. OBJECTIVE: We compared perinatal outcomes in patients with hypertension and diabetes who achieved blood pressure <130/80 vs 130 to 139/80 to 89 mm Hg. STUDY DESIGN: This was a secondary analysis of a multcenter randomized controlled trial. Participants were included in this secondary analysis if they had diabetes diagnosed prior to pregnancy or at <20 weeks of gestation and at least 2 recorded blood pressure measurements prior to delivery. Average systolic and diastolic blood pressure were calculated using ambulatory antenatal blood pressures. The primary composite outcome was preeclampsia with severe features, indicated preterm birth <35 weeks, or placental abruption. Secondary outcomes were components of the primary outcome, cesarean delivery, fetal or neonatal death, neonatal intensive care unit admission, and small for gestational age. Comparisons were made between those with an average systolic blood pressure <130 mm Hg and average diastolic blood pressure <80 mm Hg and those with an average systolic blood pressure 130 to 139 mm Hg or diastolic blood pressure 80 to 89 mm Hg using Student's t test and chi-squared tests. Multivariable log-binomial regression models were used to evaluate risk ratios between blood pressure groups for dichotomous outcomes while accounting for baseline covariates. RESULTS: Of 434 participants included, 150 (34.6%) had an average blood pressure less than 130/80 mm Hg. Participants with an average blood pressure less than 130/80 were more likely to be on antihypertensive medications at the start of pregnancy and more likely to have newly diagnosed diabetes mellitus prior to 20 weeks. Participants with an average blood pressure less than 130/80 mm Hg were less likely to have the primary adverse perinatal outcome (19.3% vs 46.5%, adjusted relative risk 0.43, 95% confidence interval 0.30-0.61, P<.01), with decreased risks specifically of preeclampsia with severe features (adjusted relative risk 0.35, 95% confidence interval 0.23-0.54) and indicated preterm birth prior to 35 weeks (adjusted relative risk 0.44, 95% confidence interval 0.24-0.79). The risk of neonatal intensive care unit admission was lower in the lower blood pressure group (adjusted relative risk 0.74, 95% confidence interval 0.59-0.94). No differences were noted in cesarean delivery (adjusted relative risk 1.04, 95% confidence interval 0.90-1.20), fetal or neonatal death (adjusted relative risk 0.59, 95% confidence interval 0.12-2.92). Small for gestational age less than the 10th percentile was lower in the lower blood pressure group (adjusted relative risk 0.37, 95% confidence interval 0.14-0.96). CONCLUSION: In those with chronic hypertension and diabetes prior to 20 weeks, achieving an average goal blood pressure of <130/80 mm Hg may be associated with improved perinatal outcomes.

20.
Connect Tissue Res ; 65(1): 26-40, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37898909

RESUMEN

PURPOSE/AIM: Cartilage injury and subsequent osteoarthritis (OA) are debilitating conditions affecting millions worldwide. As there are no cures for these ailments, novel therapies are needed to suppress disease pathogenesis. Given that joint injuries are known to produce damage-associated molecular patterns (DAMPs), our central premise is that the Toll-like receptor 4 (TLR4) pathway is a principal driver in the early response to cartilage damage and subsequent pathology. We postulate that TLR4 activation is initiated/perpetuated by DAMPs released following joint damage. Thus, antagonism of the TLR4 pathway immediately after injury may suppress the development of joint surface defects. MATERIALS AND METHODS: Two groups were utilized: (1) 8-week-old, male C57BL6 mice treated systemically with a known TLR4 antagonist and (2) mice injected with vehicle control. A full-depth cartilage lesion on the midline of the patellofemoral groove was created in the right knee of each mouse. The left knee was used as a sham surgery control. Gait changes were evaluated over 4 weeks using a quantitative gait analysis system. At harvest, knee joints were processed for pathologic assessment, Nanostring® transcript expression, and immunohistochemistry (IHC). RESULTS: Short-term treatment with a TLR4 antagonist at 14-days significantly improved relevant gait parameters; improved cartilage metrics and modified Mankin scores were also seen. Additionally, mRNA expression and IHC showed reduced expression of inflammatory mediators in animals treated with the TLR4 antagonist. CONCLUSIONS: Collectively, this work demonstrates that systemic treatment with a TLR4 antagonist is protective to further cartilage damage 14-days post-injury in a murine model of induced disease.


Asunto(s)
Enfermedades de los Cartílagos , Cartílago Articular , Osteoartritis de la Rodilla , Osteoartritis , Ratones , Masculino , Animales , Receptor Toll-Like 4 , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Osteoartritis/patología , Cartílago/patología , Enfermedades de los Cartílagos/patología , Cartílago Articular/patología , Osteoartritis de la Rodilla/patología
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