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1.
Nat Immunol ; 23(11): 1536-1550, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36271147

RESUMEN

CD40 signaling in classical type 1 dendritic cells (cDC1s) is required for CD8 T cell-mediated tumor rejection, but the underlying mechanisms are incompletely understood. Here, we identified CD40-induced genes in cDC1s, including Cd70, Tnfsf9, Ptgs2 and Bcl2l1, and examined their contributions to anti-tumor immunity. cDC1-specific inactivation of CD70 and COX-2, and global CD27 inactivation, only partially impaired tumor rejection or tumor-specific CD8 T cell expansion. Loss of 4-1BB, alone or in Cd27-/- mice, did not further impair anti-tumor immunity. However, cDC1-specific CD40 inactivation reduced cDC1 mitochondrial transmembrane potential and increased caspase activation in tumor-draining lymph nodes, reducing migratory cDC1 numbers in vivo. Similar impairments occurred during in vitro antigen presentation by Cd40-/- cDC1s to CD8+ T cells, which were reversed by re-expression of Bcl2l1. Thus, CD40 signaling in cDC1s not only induces costimulatory ligands for CD8+ T cells but also induces Bcl2l1 that sustains cDC1 survival during priming of anti-tumor responses.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias , Ratones , Animales , Antígenos CD40/genética , Presentación de Antígeno , Células Dendríticas , Ratones Endogámicos C57BL
2.
Nat Immunol ; 20(9): 1174-1185, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31406377

RESUMEN

Classical type 1 dendritic cells (cDC1s) are required for antiviral and antitumor immunity, which necessitates an understanding of their development. Development of the cDC1 progenitor requires an E-protein-dependent enhancer located 41 kilobases downstream of the transcription start site of the transcription factor Irf8 (+41-kb Irf8 enhancer), but its maturation instead requires the Batf3-dependent +32-kb Irf8 enhancer. To understand this switch, we performed single-cell RNA sequencing of the common dendritic cell progenitor (CDP) and identified a cluster of cells that expressed transcription factors that influence cDC1 development, such as Nfil3, Id2 and Zeb2. Genetic epistasis among these factors revealed that Nfil3 expression is required for the transition from Zeb2hi and Id2lo CDPs to Zeb2lo and Id2hi CDPs, which represent the earliest committed cDC1 progenitors. This genetic circuit blocks E-protein activity to exclude plasmacytoid dendritic cell potential and explains the switch in Irf8 enhancer usage during cDC1 development.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Células Dendríticas/citología , Elementos de Facilitación Genéticos/genética , Proteína 2 Inhibidora de la Diferenciación/metabolismo , Factores Reguladores del Interferón/metabolismo , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc/metabolismo , Animales , Diferenciación Celular/inmunología , Células Cultivadas , Regulación del Desarrollo de la Expresión Génica/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Represoras/metabolismo , Células Madre/citología
3.
Immunity ; 55(6): 1032-1050.e14, 2022 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35704993

RESUMEN

Conventional dendritic cells (cDCs), cDC1 and cDC2, act both to initiate immunity and maintain self-tolerance. The tryptophan metabolic enzyme indoleamine 2,3-dioxygenase 1 (IDO1) is used by cDCs in maintaining tolerance, but its role in different subsets remains unclear. At homeostasis, only mature CCR7+ cDC1 expressed IDO1 that was dependent on IRF8. Lipopolysaccharide treatment induced maturation and IDO1-dependent tolerogenic activity in isolated immature cDC1, but not isolated cDC2. However, both human and mouse cDC2 could induce IDO1 and acquire tolerogenic function when co-cultured with mature cDC1 through the action of cDC1-derived l-kynurenine. Accordingly, cDC1-specific inactivation of IDO1 in vivo exacerbated disease in experimental autoimmune encephalomyelitis. This study identifies a previously unrecognized metabolic communication in which IDO1-expressing cDC1 cells extend their immunoregulatory capacity to the cDC2 subset through their production of tryptophan metabolite l-kynurenine. This metabolic axis represents a potential therapeutic target in treating autoimmune demyelinating diseases.


Asunto(s)
Indolamina-Pirrol 2,3,-Dioxigenasa , Quinurenina , Animales , Células Dendríticas , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Quinurenina/metabolismo , Ratones , Transducción de Señal , Triptófano/metabolismo
4.
Immunity ; 54(7): 1417-1432.e7, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34004142

RESUMEN

The transcriptional repressor ZEB2 regulates development of many cell fates among somatic, neural, and hematopoietic lineages, but the basis for its requirement in these diverse lineages is unclear. Here, we identified a 400-basepair (bp) region located 165 kilobases (kb) upstream of the Zeb2 transcriptional start site (TSS) that binds the E proteins at several E-box motifs and was active in hematopoietic lineages. Germline deletion of this 400-bp region (Zeb2Δ-165mice) specifically prevented Zeb2 expression in hematopoietic stem cell (HSC)-derived lineages. Zeb2Δ-165 mice lacked development of plasmacytoid dendritic cells (pDCs), monocytes, and B cells. All macrophages in Zeb2Δ-165 mice were exclusively of embryonic origin. Using single-cell chromatin profiling, we identified a second Zeb2 enhancer located at +164-kb that was selectively active in embryonically derived lineages, but not HSC-derived ones. Thus, Zeb2 expression in adult, but not embryonic, hematopoiesis is selectively controlled by the -165-kb Zeb2 enhancer.


Asunto(s)
Elementos de Facilitación Genéticos/genética , Hematopoyesis/genética , Transcripción Genética/genética , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc/genética , Animales , Diferenciación Celular/genética , Linaje de la Célula/genética , Cromatina/genética , Células Dendríticas/fisiología , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Monocitos/fisiología
5.
Immunity ; 53(4): 759-774.e9, 2020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-32795402

RESUMEN

Development and function of conventional dendritic cell (cDC) subsets, cDC1 and cDC2, depend on transcription factors (TFs) IRF8 and IRF4, respectively. Since IRF8 and IRF4 can each interact with TF BATF3 at AP1-IRF composite elements (AICEs) and with TF PU.1 at Ets-IRF composite elements (EICEs), it is unclear how these factors exert divergent actions. Here, we determined the basis for distinct effects of IRF8 and IRF4 in cDC development. Genes expressed commonly by cDC1 and cDC2 used EICE-dependent enhancers that were redundantly activated by low amounts of either IRF4 or IRF8. By contrast, cDC1-specific genes relied on AICE-dependent enhancers, which required high IRF concentrations, but were activated by either IRF4 or IRF8. IRF8 was specifically required only by a minority of cDC1-specific genes, such as Xcr1, which could distinguish between IRF8 and IRF4 DNA-binding domains. Thus, these results explain how BATF3-dependent Irf8 autoactivation underlies emergence of the cDC1-specific transcriptional program.


Asunto(s)
Células Dendríticas/metabolismo , Elementos de Facilitación Genéticos/genética , Factores Reguladores del Interferón/genética , Animales , Regulación de la Expresión Génica/genética , Ratones , Ratones Endogámicos C57BL , Receptores de Quimiocina/genética , Transcripción Genética/genética
6.
Nature ; 607(7917): 142-148, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35732734

RESUMEN

The divergence of the common dendritic cell progenitor1-3 (CDP) into the conventional type 1 and type 2 dendritic cell (cDC1 and cDC2, respectively) lineages4,5 is poorly understood. Some transcription factors act in the commitment of already specified progenitors-such as BATF3, which stabilizes Irf8 autoactivation at the +32 kb Irf8 enhancer4,6-but the mechanisms controlling the initial divergence of CDPs remain unknown. Here we report the transcriptional basis of CDP divergence and describe the first requirements for pre-cDC2 specification. Genetic epistasis analysis7 suggested that Nfil3 acts upstream of Id2, Batf3 and Zeb2 in cDC1 development but did not reveal its mechanism or targets. Analysis of newly generated NFIL3 reporter mice showed extremely transient NFIL3 expression during cDC1 specification. CUT&RUN and chromatin immunoprecipitation followed by sequencing identified endogenous NFIL3 binding in the -165 kb Zeb2 enhancer8 at three sites that also bind the CCAAT-enhancer-binding proteins C/EBPα and C/EBPß. In vivo mutational analysis using CRISPR-Cas9 targeting showed that these NFIL3-C/EBP sites are functionally redundant, with C/EBPs supporting and NFIL3 repressing Zeb2 expression at these sites. A triple mutation of all three NFIL3-C/EBP sites ablated Zeb2 expression in myeloid, but not lymphoid progenitors, causing the complete loss of pre-cDC2 specification and mature cDC2 development in vivo. These mice did not generate T helper 2 (TH2) cell responses against Heligmosomoides polygyrus infection, consistent with cDC2 supporting TH2 responses to helminths9-11. Thus, CDP divergence into cDC1 or cDC2 is controlled by competition between NFIL3 and C/EBPs at the -165 kb Zeb2 enhancer.


Asunto(s)
Diferenciación Celular , Células Dendríticas , Elementos de Facilitación Genéticos , Mutación , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Diferenciación Celular/genética , Células Dendríticas/clasificación , Células Dendríticas/citología , Células Dendríticas/patología , Elementos de Facilitación Genéticos/genética , Epistasis Genética , Proteína 2 Inhibidora de la Diferenciación , Linfocitos/citología , Ratones , Células Mieloides/citología , Nematospiroides dubius/inmunología , Proteínas Represoras , Células Th2/citología , Células Th2/inmunología , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc/genética
7.
Proc Natl Acad Sci U S A ; 121(15): e2315659121, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38564635

RESUMEN

Monocytes comprise two major subsets, Ly6Chi classical monocytes and Ly6Clo nonclassical monocytes. Notch2 signaling in Ly6Chi monocytes triggers transition to Ly6Clo monocytes, which require Nr4a1, Bcl6, Irf2, and Cebpb. By comparison, less is known about transcriptional requirements for Ly6Chi monocytes. We find transcription factor CCAAT/enhancer-binding protein alpha (C/EBPα) is highly expressed in Ly6Chi monocytes, but down-regulated in Ly6Clo monocytes. A few previous studies described the requirement of C/EBPα in the development of neutrophils and eosinophils. However, the role of C/EBPα for in vivo monocyte development has not been understood. We deleted the Cebpa +37 kb enhancer in mice, eliminating hematopoietic expression of C/EBPα, reproducing the expected neutrophil defect. Surprisingly, we also found a severe and selective loss of Ly6Chi monocytes, while preserving Ly6Clo monocytes. We find that BM progenitors from Cebpa +37-/- mice rapidly progress through the monocyte progenitor stage to develop directly into Ly6Clo monocytes even in the absence of Notch2 signaling. These results identify a previously unrecognized role for C/EBPα in maintaining Ly6Chi monocyte identity.


Asunto(s)
Regulación de la Expresión Génica , Monocitos , Animales , Ratones , Ratones Endogámicos C57BL , Monocitos/metabolismo , Factores de Transcripción/metabolismo
8.
Proc Natl Acad Sci U S A ; 120(35): e2220853120, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37607223

RESUMEN

Ly6Clo monocytes are a myeloid subset that specializes in the surveillance of vascular endothelium. Ly6Clo monocytes have been shown to derive from Ly6Chi monocytes. NOTCH2 signaling has been implicated as a trigger for Ly6Clo monocyte development, but the basis for this effect is unclear. Here, we examined the impact of NOTCH2 signaling of myeloid progenitors on the development of Ly6Clo monocytes in vitro. NOTCH2 signaling induced by delta-like ligand 1 (DLL1) efficiently induced the transition of Ly6Chi TREML4- monocytes into Ly6Clo TREML4+ monocytes. We further identified two additional transcriptional requirements for development of Ly6Clo monocytes. Deletion of BCL6 from myeloid progenitors abrogated development of Ly6Clo monocytes. IRF2 was also required for Ly6Clo monocyte development in a cell-intrinsic manner. DLL1-induced in vitro transition into Ly6Clo TREML4+ monocytes required IRF2 but unexpectedly could occur in the absence of NUR77 or BCL6. These results imply a transcriptional hierarchy for these factors in controlling Ly6Clo monocyte development.


Asunto(s)
Endotelio Vascular , Monocitos , Hematopoyesis , Transducción de Señal
9.
Proc Natl Acad Sci U S A ; 120(13): e2219956120, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36940342

RESUMEN

The events that initiate autoimmune diabetes in nonobese diabetic (NOD) mice remain poorly understood. CD4+ and CD8+ T cells are both required to develop disease, but their relative roles in initiating disease are unclear. To test whether CD4+ T cell infiltration into islets requires damage to ß cells induced by autoreactive CD8+ T cells, we inactivated Wdfy4 in nonobese diabetic (NOD) mice (NOD.Wdfy4-/--) using CRISPR/Cas9 targeting to eliminate cross-presentation by type 1 conventional dendritic cells (cDC1s). Similar to C57BL/6 Wdfy4-/- mice, cDC1 in NOD.Wdfy4-/- mice are unable to cross-present cell-associated antigens to prime CD8+ T cells, while cDC1 from heterozygous NOD.Wdfy4+/- mice cross-present normally. Further, NOD.Wdfy4-/- mice fail to develop diabetes while heterozygous NOD.Wdfy4+/- mice develop diabetes similarly to wild-type NOD mice. NOD.Wdfy4-/- mice remain capable of processing and presenting major histocompatibility complex class II (MHC-II)-restricted autoantigens and can activate ß cell-specific CD4+ T cells in lymph nodes. However, disease in these mice does not progress beyond peri-islet inflammation. These results indicate that the priming of autoreactive CD8+ T cells in NOD mice requires cross-presentation by cDC1. Further, autoreactive CD8+ T cells appear to be required not only to develop diabetes, but to recruit autoreactive CD4+ T cells into islets of NOD mice, perhaps in response to progressive ß cell damage.


Asunto(s)
Diabetes Mellitus Tipo 1 , Islotes Pancreáticos , Ratones , Animales , Ratones Endogámicos NOD , Linfocitos T CD8-positivos , Ratones Endogámicos C57BL , Antígenos de Histocompatibilidad Clase II
11.
Eur J Immunol ; 53(9): e2250201, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37424050

RESUMEN

In vitro culture of bone marrow (BM) with Fms-like tyrosine kinase 3 ligand (Flt3L) is widely used to study development and function of type 1 conventional dendritic cells (cDC1). Hematopoietic stem cells (HSCs) and many progenitor populations that possess cDC1 potential in vivo do not express Flt3 and thus may not contribute to Flt3L-mediated cDC1 production in vitro. Here, we present a KitL/Flt3L protocol that recruits such HSCs and progenitors into the production of cDC1. Kit ligand (KitL) is used to expand HSCs and early progenitors lacking Flt3 expression into later stage where Flt3 is expressed. Following this initial KitL phase, a second Flt3L phase is used to support the final production of DCs. With this two-stage culture, we achieved approximately tenfold increased production of both cDC1 and cDC2 compared to Flt3L culture. cDC1 derived from this culture are similar to in vivo cDC1 in their dependence on IRF8, ability to produce IL-12, and induction of tumor regression in cDC1-deficient tumor-bearing mice. This KitL/Flt3L system for cDC1 production will be useful in further analysis of cDC1 that rely on in vitro generation from BM.


Asunto(s)
Células Madre Hematopoyéticas , Factor de Células Madre , Ratones , Animales , Médula Ósea , Células de la Médula Ósea , Células Dendríticas
12.
Psychol Med ; 54(4): 721-731, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37614188

RESUMEN

BACKGROUND: In a birth-cohort study, we followed offspring with prenatal cocaine exposure (PCE) to investigate longitudinal associations of PCE with self-reported behavioral adjustment from early adolescence to emerging adulthood (EA). Environmental pathways (family functioning, non-kinship care, maltreatment) were specified as potential mediators of PCE. METHODS: Participants were 372 (190 PCE; 47% male), primarily Black, low socioeconomic status, enrolled at birth. Internalizing and externalizing behaviors were assessed using Youth Self-Report at ages 12 and 15 and Adult Self-Report at age 21. Extended random-intercept cross-lagged panel modeling was used to account for potential bidirectional relationships between internalizing and externalizing behaviors over time, examining potential mediators. RESULTS: Adjusting for covariates, significant indirect effects were found for each mediator at different ages. For family functioning, these were both internalizing (ß = 0.83, p = 0.04) and externalizing behaviors (ß = 1.58, p = 0.02) at age 12 and externalizing behaviors at age 15 (ß = 0.51, p = 0.03); for non-kinship care, externalizing behaviors at ages 12 (ß = 0.63, p = 0.02) and 15 (ß = 0.20, p = 0.03); and for maltreatment, both internalizing and externalizing behaviors at ages 15 (ß = 0.64, p = 0.02 for internalizing; ß = 0.50, p = 0.03 for externalizing) and 21 (ß = 1.39, p = 0.01 for internalizing; ß = 1.11, p = 0.01 for externalizing). Direct associations of PCE with internalizing and externalizing behaviors were not observed, nor cross-lagged relationships between internalizing and externalizing behaviors. CONCLUSIONS: Negative associations of PCE with behavioral adjustment persist into EA via environmental pathways, specifying intervention points to disrupt adverse pathways toward healthy development.


Asunto(s)
Conducta del Adolescente , Cocaína , Embarazo , Femenino , Adulto , Adolescente , Recién Nacido , Humanos , Masculino , Adulto Joven , Niño , Autoinforme , Estudios de Cohortes , Estudios Longitudinales , Cocaína/efectos adversos
13.
Appl Nurs Res ; 77: 151800, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38796255

RESUMEN

PURPOSE: Virtual reality technology has been used to establish a risk-free environment in which students can practice psychiatric nursing. A quasi-experimental study was conducted to examine the effects of a virtual reality (VR) based mental health nursing simulation on practice performance of undergraduate nursing students. METHODS: A quasi-experimental, pre- and post-test design was used. A total of 68 students were randomly assigned to an experimental group (n = 32) and a control group (n = 36). The control group received conventional simulation using text scenario-based role play. The intervention group received VR software consisting of 360° video clips and related quiz questions. RESULTS: The self-reported perceived competency in nursing performance showed no statistically significant improvement in the experimental group, whereas the control group showed a statistically significant improvement in symptom management (t = 2.84, p = 0.007) and nurse-patient interaction (t = 2.10, p = 0.043). Scores from the assessor showed better performance scores in the experimental group in symptom management (t = -2.62, p = 0.011), violence risk management (t = -3.42, p = 0.001), and nurse-patient interaction (t = -3.12, p = 0.003). CONCLUSIONS: The findings of this study indicate the potential of using VR for optimized mental health nursing simulation. VR technology allowed realistic experiences which may ensure students have a more comprehensive understanding of mentally ill patients and in doing so, overcome barriers of traditional simulation, resulting in better learning outcomes.


Asunto(s)
Enfermería Psiquiátrica , Realidad Virtual , Humanos , Enfermería Psiquiátrica/educación , Enfermería Psiquiátrica/métodos , Femenino , Masculino , Adulto Joven , Adulto , Bachillerato en Enfermería/métodos , Estudiantes de Enfermería/psicología , Estudiantes de Enfermería/estadística & datos numéricos
14.
Clin Infect Dis ; 76(76 Suppl1): S132-S139, 2023 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-37074438

RESUMEN

BACKGROUND: Pediatric exposures to unsafe sources of water, unsafely managed sanitation, and animals are prevalent in low- and middle-income countries. In the Vaccine Impact on Diarrhea in Africa case-control study, we examined associations between these risk factors and moderate-to-severe diarrhea (MSD) in children <5 years old in The Gambia, Kenya, and Mali. METHODS: We enrolled children <5 years old seeking care for MSD at health centers; age-, sex-, and community-matched controls were enrolled at home. Conditional logistic regression models, adjusted for a priori confounders, were used to evaluate associations between MSD and survey-based assessments of water, sanitation, and animals living in the compound. RESULTS: From 2015 to 2018, 4840 cases and 6213 controls were enrolled. In pan-site analyses, children with drinking water sources below "safely managed" (onsite, continuously accessible sources of good water quality) had 1.5-2.0-fold higher odds of MSD (95% confidence intervals [CIs] ranging from 1.0 to 2.5), driven by rural site results (The Gambia and Kenya). In the urban site (Mali), children whose drinking water source was less available (several hours/day vs all the time) had higher odds of MSD (matched odds ratio [mOR]: 1.4, 95% CI: 1.1, 1.7). Associations between MSD and sanitation were site-specific. Goats were associated with slightly increased odds of MSD in pan-site analyses, whereas associations with cows and fowl varied by site. CONCLUSIONS: Poorer types and availability of drinking water sources were consistently associated with MSD, whereas the impacts of sanitation and household animals were context-specific. The association between MSD and access to safely managed drinking water sources post-rotavirus introduction calls for transformational changes in drinking water services to prevent acute child morbidity from MSD.


Asunto(s)
Agua Potable , Saneamiento , Femenino , Animales , Bovinos , Kenia/epidemiología , Saneamiento/métodos , Gambia/epidemiología , Malí/epidemiología , Estudios de Casos y Controles , Diarrea/epidemiología , Diarrea/prevención & control , Diarrea/etiología , Factores de Riesgo
15.
Clin Infect Dis ; 76(76 Suppl1): S106-S113, 2023 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-37074432

RESUMEN

BACKGROUND: Giardia has been associated with reduced risk of diarrhea in children in low-resource settings, but the mechanism underlying this association is unknown. To assess whether Giardia may shape colonization or infection with other enteric pathogens and impact associations with diarrhea, we examined Giardia and enteric pathogen codetection among children <5 years old in Kenya, The Gambia, and Mali as part of the Vaccine Impact on Diarrhea in Africa study. METHODS: We tested for Giardia and other enteric pathogens using enzyme-linked immunosorbent assays and real-time polymerase chain reaction (PCR) on stool, respectively. We evaluated associations between Giardia and enteric pathogen detection using multivariable logistic regression models separately for children with moderate-to-severe diarrhea (MSD, cases) and free of diarrhea (controls). RESULTS: Among 11 039 enrolled children, Giardia detection was more common among controls (35%) than cases (28%, P < .001). Campylobacter coli/jejuni detection was associated with Giardia in controls in The Gambia (adjusted odds ratio [aOR] [95% confidence interval {CI}]: 1.51 [1.22‒1.86]) and cases across all sites (1.16 [1.00‒1.33]). Among controls, the odds of astrovirus (1.43 [1.05‒1.93]) and Cryptosporidium spp. (1.24 [1.06‒1.46]) detection were higher among children with Giardia. Among cases, the odds of rotavirus detection were lower in children with Giardia in Mali (.45 [.30‒.66]) and Kenya (.31 [.17‒.56]). CONCLUSIONS: Giardia was prevalent in children <5 years old and was associated with detection of other enteric pathogens, with differing associations in cases versus controls and by site. Giardia may affect colonization or infection by certain enteric pathogens associated with MSD, suggesting an indirect mechanism of clinical impact.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Vacunas , Humanos , Niño , Lactante , Preescolar , Criptosporidiosis/diagnóstico , Criptosporidiosis/epidemiología , Criptosporidiosis/prevención & control , Giardia , Estudios de Casos y Controles , Diarrea/epidemiología , Diarrea/complicaciones , Kenia/epidemiología , Heces
16.
Clin Infect Dis ; 76(76 Suppl1): S140-S152, 2023 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-37074442

RESUMEN

BACKGROUND: The magnitude of pediatric enteric pathogen exposures in low-income settings necessitates substantive water and sanitation interventions, including animal feces management. We assessed associations between pediatric enteric pathogen detection and survey-based water, sanitation, and animal characteristics within the Vaccine Impact on Diarrhea in Africa case-control study. METHODS: In The Gambia, Kenya, and Mali, we assessed enteric pathogens in stool of children aged <5 years with moderate-to-severe diarrhea and their matched controls (diarrhea-free in prior 7 days) via the TaqMan Array Card and surveyed caregivers about household drinking water and sanitation conditions and animals living in the compound. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated using modified Poisson regression models, stratified for cases and controls and adjusted for age, sex, site, and demographics. RESULTS: Bacterial (cases, 93%; controls, 72%), viral (63%, 56%), and protozoal (50%, 38%) pathogens were commonly detected (cycle threshold <35) in the 4840 cases and 6213 controls. In cases, unimproved sanitation (RR, 1.56; 95% CI, 1.12-2.17), as well as cows (RR, 1.61; 95% CI, 1.16-2.24) and sheep (RR, 1.48; 95% CI, 1.11-1.96) living in the compound, were associated with Shiga toxin-producing Escherichia coli. In controls, fowl (RR, 1.30; 95% CI, 1.15-1.47) were associated with Campylobacter spp. In controls, surface water sources were associated with Cryptosporidium spp., Shigella spp., heat-stable toxin-producing enterotoxigenic E. coli, and Giardia spp. CONCLUSIONS: Findings underscore the importance of enteric pathogen exposure risks from animals alongside more broadly recognized water and sanitation risk factors in children.


Asunto(s)
Diarrea , Heces , Saneamiento , Abastecimiento de Agua , Estudios de Casos y Controles , Diarrea/epidemiología , Diarrea/microbiología , Diarrea/prevención & control , Microbioma Gastrointestinal , Heces/microbiología , Humanos , Animales , Bovinos , Niño , Vacunas contra el Cólera/administración & dosificación
18.
Nano Lett ; 22(1): 380-388, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-34958577

RESUMEN

Nanometer optical coatings with absorbing materials allow the tuning of structured absorption spectra, thus developing ultrathin color devices. However, these coatings are limited by the narrow bandwidth and tunability of wavelength that restrict the chroma and hue characteristics of colors, respectively, apart from imposing adverse thermal problems under sunlight exposure. Here, we demonstrate that inversely designed TiN/ZnS/Ag coatings attain a wide color gamut in the trilayer configuration and efficiently dissipate heat through thermal radiation when transfer-printed on high-emissivity polymers. Daytime experiments reveal that fabricated optical films yield an almost color-independent heat dissipation rate against solar heating. Moreover, they outperform commercial paints of the same color when applied to three-dimensional miniature houses. All magenta, green, cyan, and yellow optical films lower the roof temperature by 10, 6, 8, and 2 °C below one sun irradiance, respectively, compared to their paint counterparts; the temperature gradient increases directly with the level of sunlight.

19.
Opt Express ; 30(23): 42406-42414, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36366695

RESUMEN

We demonstrated that a well-designed nanopatterned cover improves photovoltaic efficiency across a wide range of incident angles (θ). A nanopatterned cover was created using an integrated ray-wave optics simulation to maximize the light absorption of the surface-textured Si photovoltaic device. A hexagonally arranged nanocone array with a 300 nm pitch was formed into a polymer using nanoimprinting, and the nanostructured polymer was then attached to a glass cover with an index-matching adhesive. Angle-resolved current density-voltage measurements on Si photovoltaic devices showed that the nanopatterned glass cover yielded a 2-13% enhancement in power conversion efficiency at θ = 0-60°, which accounted for its broadband antireflective feature. We performed all-season-perspective simulations based on the results of the integrated ray-wave optics simulations and solar altitude database of South Korea, which validated the sustainability of the developed nanopatterned cover during significant seasonal fluctuations.

20.
Pharm Res ; 39(5): 989-999, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35441319

RESUMEN

PURPOSE: Teriparatide is an effective drug for the treatment of osteoporosis. This study examines the relationship between the drug delivery properties of the solid formulation with teriparatide and the pharmacokinetic properties of teriparatide in vivo. METHODS: Teriparatide microneedles with different dissolution rates were prepared using sucrose and carboxymethylcellulose (CMC). There were three aspects of this study: (1) The dissolution rate of teriparatide from both formulations (sucrose and CMC) was measured in vitro. (2) After administration into porcine skin ex vivo, the diffusion rate of FITC-dextran was observed using a confocal microscope. (3) Pharmacokinetic studies were performed in rats and pharmacokinetic data compared with the release rate and the diffusion pattern. RESULTS: In the in vitro dissolution experiment, 80% of teriparatide was released within 30 min from the CMC MNs, whereas 80% of teriparatide was released within 10 min from the sucrose MNs. After 30 min, the fluorescence intensity on the surface of the MNs was 40% of the initial intensity for sucrose MNs and 90% for CMC MNs. In the pharmacokinetic study, the Cmax values of the CMC and sucrose MNs were 868 pg/mL and 6809 pg/mL, respectively, and the AUClast values were 6771 pg*hr/mL for the CMC MNs and 17,171 pg*hr/mL for the sucrose MNs. CONCLUSIONS: When teriparatide is delivered into the skin using microneedles, the release rate from the solid formulation determines the drug's pharmacokinetic properties. The diffusion pattern of fluorescence into the skin can be used to anticipate the pharmacokinetic properties of the drug.


Asunto(s)
Agujas , Teriparatido , Administración Cutánea , Animales , Carboximetilcelulosa de Sodio , Sistemas de Liberación de Medicamentos , Microinyecciones , Preparaciones Farmacéuticas , Ratas , Piel , Sacarosa , Porcinos
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