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1.
Nature ; 571(7763): 122-126, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31189952

RESUMO

Antibodies secreted into mucosal barriers serve to protect the host from a variety of pathogens, and are the basis for successful vaccines1. In type I mucosa (such as the intestinal tract), dimeric IgA secreted by local plasma cells is transported through polymeric immunoglobulin receptors2 and mediates robust protection against viruses3,4. However, owing to the paucity of polymeric immunoglobulin receptors and plasma cells, how and whether antibodies are delivered to the type II mucosa represented by the lumen of the lower female reproductive tract remains unclear. Here, using genital herpes infection in mice, we show that primary infection does not establish plasma cells in the lamina propria of the female reproductive tract. Instead, upon secondary challenge with herpes simplex virus 2, circulating memory B cells that enter the female reproductive tract serve as the source of rapid and robust antibody secretion into the lumen of this tract. CD4 tissue-resident memory T cells secrete interferon-γ, which induces expression of chemokines, including CXCL9 and CXCL10. Circulating memory B cells are recruited to the vaginal mucosa in a CXCR3-dependent manner, and secrete virus-specific IgG2b, IgG2c and IgA into the lumen. These results reveal that circulating memory B cells act as a rapidly inducible source of mucosal antibodies in the female reproductive tract.


Assuntos
Anticorpos/imunologia , Linfócitos B/citologia , Linfócitos B/imunologia , Movimento Celular/imunologia , Memória Imunológica/imunologia , Vagina/citologia , Vagina/imunologia , Animais , Formação de Anticorpos/imunologia , Linfócitos T CD4-Positivos/imunologia , Feminino , Herpes Simples/imunologia , Herpes Simples/virologia , Herpesvirus Humano 2/imunologia , Imunização , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores CXCR3/imunologia , Vagina/virologia
2.
Nicotine Tob Res ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584415

RESUMO

INTRODUCTION: Youth tobacco use remains a critical public health concern, and childhood use of candy tobacco imitation products (CTIP) is associated with cigarette use among youth. However, no research has examined the full extent of CTIP available for purchase in the United States. AIMS AND METHODS: We conducted a content analysis of CTIP available on English-language, US-based websites. We identified sites that marketed CTIP utilizing Google and candy retail websites, examining each product for product names, the tobacco product being replicated (eg, cigar and cigarette), manufacturer, candy flavor, images, product rating, pack color, and if the product had packaging that may appeal to youth. RESULTS: We found 66 CTIP available. The most popular CTIP were cigars, with 39 separate products (59%), followed by candy cigarettes-14 products (21%), candy pipes-8 products (12%), and chewing tobacco-5 products (8%). In the 52 products where packaging design was available, 39 (75%) had packaging that may appeal to youth. CONCLUSIONS: CTIP, many of which contain packaging appealing to youth, are widely available for purchase online across the United States. These findings could stimulate policy actions, such as removal of CTIP from popular retail websites, labeling of CTIP as potentially dangerous to youth, or age verification requirements for purchasing CTIP. IMPLICATIONS: CTIP continues to be sold on the internet despite research indicating candy cigarette product use by youth increases their likelihood of smoking. We conducted research to understand the extent to which CTIP are sold on the internet and whether these products are being marketed to youth. The results provide evidence that some of the largest retail companies in the world continue to sell CTIP, and the majority are sold in packaging that likely appeals to youth. The results suggest that further research into the market for these products is needed, and regulatory measures should be considered to prevent CTIP from leading to youth tobacco use.

3.
Am J Respir Crit Care Med ; 208(3): 290-300, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37209133

RESUMO

Rationale: Increasing survival of extremely preterm infants with a stable rate of severe intraventricular hemorrhage represents a growing health risk for neonates. Objectives: To evaluate the role of early hemodynamic screening (HS) on the risk of death or severe intraventricular hemorrhage. Methods: All eligible patients 22-26+6 weeks' gestation born and/or admitted <24 hours postnatal age were included. As compared with standard neonatal care for control subjects (January 2010-December 2017), patients admitted in the second epoch (October 2018-April 2022) were exposed to HS using targeted neonatal echocardiography at 12-18 hours. Measurements and Main Results: A primary composite outcome of death or severe intraventricular hemorrhage was decided a priori using a 10% reduction in baseline rate to calculate sample size. A total of 423 control subjects and 191 screening patients were recruited with a mean gestation and birth weight of 24.7 ± 1.5 weeks and 699 ± 191 g, respectively. Infants born at 22-23 weeks represented 41% (n = 78) of the HS epoch versus 32% (n = 137) of the control subjects (P = 0.004). An increase in perinatal optimization (e.g., antepartum steroids) but with a decline in maternal health (e.g., increased obesity) was seen in the HS versus control epoch. A reduction in the primary outcome and each of severe intraventricular hemorrhage, death, death in the first postnatal week, necrotizing enterocolitis, and severe bronchopulmonary dysplasia was seen in the screening era. After adjustment for perinatal confounders and time, screening was independently associated with survival free of severe intraventricular hemorrhage (OR 2.09, 95% CI [1.19, 3.66]). Conclusions: Early HS and physiology-guided care may be an avenue to further improve neonatal outcomes; further evaluation is warranted.


Assuntos
Displasia Broncopulmonar , Doenças do Prematuro , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Lactente Extremamente Prematuro , Doenças do Prematuro/diagnóstico por imagem , Idade Gestacional , Hemorragia
4.
Acta Paediatr ; 113(4): 692-699, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38084834

RESUMO

AIM: Acute kidney injury (AKI) in neonates is associated with longer hospital stays and higher mortality rates. However, there is significant variability in prevalence rates of AKI and the true burden is incompletely understood. In November 2020, the University of Iowa Stead Family Children's Hospital Neonatal Intensive Care Unit implemented a creatinine screening protocol to enhance kidney function monitoring. We sought to evaluate adherence to the protocol to determine if increased surveillance led to increased detection of AKI events. METHODS: A retrospective chart review was conducted for neonates born at <30 weeks' gestation admitted between 2015 and 2020. We reviewed 100 charts in both the pre (2015-2016) and post (2020-2021) implementation era of the AKI surveillance protocol. AKI was defined according to neonatal modified KDIGO criteria. RESULTS: Following implementation of the protocol, neonates were significantly more likely to have creatinine checked (p < 0.001). Serum creatinine was drawn according to protocol guidelines 68% of the time, and 42% of patients (34/82) had an 80% or higher adherence to the protocol. There was a significant increase in detection of AKI in the post-protocol cohort (13/82, incidence of 16%) compared to the pre-protocol cohort (5/83, incidence of 6%), (p = 0.047). CONCLUSION: The implementation of a serum creatinine screening protocol increased the frequency of creatinine draws and detection of AKI.


Assuntos
Injúria Renal Aguda , Unidades de Terapia Intensiva Neonatal , Recém-Nascido , Criança , Feminino , Humanos , Creatinina , Estudos Retrospectivos , Incidência , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Fatores de Risco , Literatura de Revisão como Assunto
5.
Proc Natl Acad Sci U S A ; 117(27): 15837-15845, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571957

RESUMO

Despite broad appreciation of their clinical utility, it has been unclear how vitamin B12 and folic acid (FA) function at the molecular level to directly prevent their hallmark symptoms of deficiency like anemia or birth defects. To this point, B12 and FA have largely been studied as cofactors for enzymes in the one-carbon (1C) cycle in facilitating the de novo generation of nucleotides and methylation of DNA and protein. Here, we report that B12 and FA function as natural antagonists of aryl hydrocarbon receptor (AhR). Our studies indicate that B12 and FA bind AhR directly as competitive antagonists, blocking AhR nuclear localization, XRE binding, and target gene induction mediated by AhR agonists like 2,3,7,8-tetrachlorodibenzodioxin (TCDD) and 6-formylindolo[3,2-b]carbazole (FICZ). In mice, TCDD treatment replicated many of the hallmark symptoms of B12/FA deficiency and cotreatment with aryl hydrocarbon portions of B12/FA rescued mice from these toxic effects. Moreover, we found that B12/FA deficiency in mice induces AhR transcriptional activity and accumulation of erythroid progenitors and that it may do so in an AhR-dependent fashion. Consistent with these results, we observed that human cancer samples with deficient B12/FA uptake demonstrated higher transcription of AhR target genes and lower transcription of pathways implicated in birth defects. In contrast, there was no significant difference observed between samples with mutated and intact 1C cycle proteins. Thus, we propose a model in which B12 and FA blunt the effect of natural AhR agonists at baseline to prevent the symptoms that arise with AhR overactivation.


Assuntos
Ácido Fólico/metabolismo , Desnutrição/metabolismo , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Receptores de Hidrocarboneto Arílico/metabolismo , Vitamina B 12/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Carbazóis/farmacologia , Anormalidades Congênitas , Feminino , Deficiência de Ácido Fólico/tratamento farmacológico , Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias , Dibenzodioxinas Policloradas/farmacologia , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/genética , Deficiência de Vitamina B 12/tratamento farmacológico
6.
Proc Natl Acad Sci U S A ; 117(29): 17240-17248, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32632017

RESUMO

Probabilistic bet hedging, a strategy to maximize fitness in unpredictable environments by matching phenotypic variability to environmental variability, is theorized to account for the evolution of various fate-specification decisions, including viral latency. However, the molecular mechanisms underlying bet hedging remain unclear. Here, we report that large variability in protein abundance within individual herpesvirus virion particles enables probabilistic bet hedging between viral replication and latency. Superresolution imaging of individual virions of the human herpesvirus cytomegalovirus (CMV) showed that virion-to-virion levels of pp71 tegument protein-the major viral transactivator protein-exhibit extreme variability. This super-Poissonian tegument variability promoted alternate replicative strategies: high virion pp71 levels enhance viral replicative fitness but, strikingly, impede silencing, whereas low virion pp71 levels reduce fitness but promote silencing. Overall, the results indicate that stochastic tegument packaging provides a mechanism enabling probabilistic bet hedging between viral replication and latency.


Assuntos
Citomegalovirus/genética , Citomegalovirus/fisiologia , Proteínas Virais/metabolismo , Latência Viral/genética , Latência Viral/fisiologia , Evolução Biológica , Infecções por Citomegalovirus , Regulação Viral da Expressão Gênica , Humanos , Monócitos , Vírion/metabolismo , Replicação Viral
7.
J Infect Dis ; 225(3): 374-384, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34718647

RESUMO

BACKGROUND: The underlying immunologic deficiencies enabling severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection are currently unknown. We describe deep longitudinal immune profiling of a transplant recipient hospitalized twice for coronavirus disease 2019 (COVID-19). METHODS: A 66-year-old male renal transplant recipient was hospitalized with COVID-19 March 2020 then readmitted to the hospital with COVID-19 233 days after initial diagnosis. Virologic and immunologic investigations were performed on samples from the primary and secondary infections. RESULTS: Whole viral genome sequencing and phylogenetic analysis revealed that viruses causing both infections were caused by distinct genetic lineages without evidence of immune escape mutations. Longitudinal comparison of cellular and humoral responses during primary SARS-CoV-2 infection revealed that this patient responded to the primary infection with low neutralization titer anti-SARS-CoV-2 antibodies that were likely present at the time of reinfection. CONCLUSIONS: The development of neutralizing antibodies and humoral memory responses in this patient failed to confer protection against reinfection, suggesting that they were below a neutralizing titer threshold or that additional factors may be required for efficient prevention of SARS-CoV-2 reinfection. Development of poorly neutralizing antibodies may have been due to profound and relatively specific reduction in naive CD4 T-cell pools. Seropositivity alone may not be a perfect correlate of protection in immunocompromised patients.


Assuntos
COVID-19 , Reinfecção , Transplantados , Idoso , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Humanos , Masculino , Transplante de Órgãos , Filogenia , Reinfecção/imunologia , Reinfecção/virologia , SARS-CoV-2/genética
8.
Curr Opin Pediatr ; 34(2): 165-169, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35034079

RESUMO

PURPOSE OF REVIEW: Ventilation of periviable infants born at 22-23 weeks gestation remains a challenge in neonatology. This review highlights the evidence surrounding the use of first intention high-frequency jet ventilation (HFJV) in infants born near the limits of viability with a review of pulmonary fetal development and a focused overview of HFJV strategies including an in-depth analysis of the management strategies used in the initial randomized trials. RECENT FINDINGS: A paucity of recent trials exists, with no randomized control trials assessing the use of first intention HFJV performed in the last 25 years. A retrospective observational cohort trial of the use of HFJV for infants born at less than 750 g has been recently published demonstrating the efficacy of HFJV for this population even with 2.0-mm endotracheal tubes. SUMMARY: The lack of recent randomized trials contributes to the controversy surrounding the use of first intention HFJV. Although new research is needed in the area, this review includes the ventilation strategy of an experienced center with a focus on the use of first intention HFJV for the care of premature infants born less than 24 weeks gestation.


Assuntos
Ventilação em Jatos de Alta Frequência , Síndrome do Desconforto Respiratório do Recém-Nascido , Humanos , Lactente , Recém-Nascido , Intenção , Estudos Observacionais como Assunto , Respiração Artificial , Estudos Retrospectivos
9.
Medicina (Kaunas) ; 58(2)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35208499

RESUMO

Background and Objective: Hyposalivation and xerostomia can result from a variety of conditions. Diagnosis is based on a combination of medical history, clinical and serological parameters, imaging, and minor salivary gland biopsy when indicated. The Objective was to characterize microscopic changes in minor salivary gland biopsies taken in patients with xerostomia. Materials and Methods: 10-year retrospective analysis of minor salivary gland biopsies, 2007-2017. Histomorphometric analysis included gland architecture, fibrosis, fat replacement, inflammation and stains for IgG/IgG4, when relevant. Results: 64 consecutive biopsies, of which 54 had sufficient tissue for diagnosis of Sjogren's Syndrome (SS) were included (18 males, 46 females, average age 56 (±12.5) years). Only 12 (22.2%) were microscopically consistent with SS, none stained for IgG4. Medical conditions were recorded in 40 (63%), most frequently hypertension and hyperlipidemia (28% each). Medications were used by 45 (70%), of which in 50% more than one. Xerostomia in non-SS cases was supported by abnormal gland morphology, including acinar atrophy, fibrosis and fatty replacement. All morphological abnormalities are correlated with age, while fatty replacement correlated with abnormal lipid metabolism. Multiple medications correlated with microscopic features which did not correspond with SS. Conclusions: SS was confirmed in a minority of cases, while in the majority fatty replacement, fibrosis and multiple medications can explain xerostomia, and are related to aging and medical conditions. Medical history and auxiliary tests could lead to correct diagnosis in non-SS patients, avoiding biopsy. The necessity of a diagnostic biopsy should be given serious consideration only after all other diagnostic modalities have been employed.


Assuntos
Glândulas Salivares Menores , Síndrome de Sjogren , Atrofia , Biópsia , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Glândulas Salivares Menores/patologia , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/epidemiologia
10.
J Virol ; 94(22)2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-32878886

RESUMO

Herpes simplex virus 1 (HSV-1) and HSV-2 can efficiently establish lifelong, transcriptionally silent latency states in sensory neurons to escape host detection. While host factors have previously been associated with long-range insulators in the viral genome, it is still unknown whether host transcription factors can repress viral genes more proximately to promote latency in dorsal root ganglion (DRG) neurons. Here, we assessed whether RUNX (runt-related transcription factor) transcription factors, which are critical in the development of sensory neurons, could be binding HSV-1 genome directly to suppress viral gene expression and lytic infection. Using previously published transcriptome sequencing data, we confirmed that mouse DRG neurons highly express Runx1 mRNA. Through computational analysis of HSV-1 and HSV-2 genomes, we observed that putative RUNX consensus binding sites (CBSs) were more enriched and more closely located to viral gene transcription start sites than would be expected by chance. We further found that RUNX CBSs were significantly more enriched among genomes of herpesviruses compared to those of nonherpesviruses. Utilizing an in vitro model of HSV-1 infection, we found that overexpressed RUNX1 could bind putative binding sites in the HSV-1 genome, repress numerous viral genes spanning all three kinetic classes, and suppress productive infection. In contrast, knockdown of RUNX1 in neuroblastoma cells induced viral gene expression and increased HSV-1 infection in vitro In sum, these data support a novel role for RUNX1 in directly binding herpesvirus genome, silencing the transcription of numerous viral genes, and ultimately limiting overall infection.IMPORTANCE Infecting 90% of the global population, HSV-1 and HSV-2 represent some of the most prevalent viruses in the world. Much of their success can be attributed to their ability to establish lifelong latent infections in the dorsal root ganglia (DRG). It is still largely unknown, however, how host transcription factors are involved in establishing this latency. Here, we report that RUNX1, expressed highly in DRG, binds HSV-1 genome, represses transcription of numerous viral genes, and suppresses productive in vitro infection. Our computational work further suggests this strategy may be used by other herpesviruses to reinforce latency in a cell-specific manner.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Herpesviridae/genética , Herpesviridae/fisiologia , Herpesvirus Humano 1/efeitos dos fármacos , Animais , Sítios de Ligação , Subunidade alfa 2 de Fator de Ligação ao Core/farmacologia , Gânglios Espinais/virologia , Regulação Viral da Expressão Gênica , Técnicas de Silenciamento de Genes , Genoma Viral , Células HEK293 , Herpes Simples/virologia , Herpesvirus Humano 1/fisiologia , Humanos , Camundongos , Células Receptoras Sensoriais/virologia , Gânglio Trigeminal/virologia , Ativação Viral/fisiologia , Latência Viral/fisiologia
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