Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
JMIR Res Protoc ; 13: e52658, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483470

RESUMO

BACKGROUND: In the United States, autistic people face high rates of co-occurring mental illnesses and premature death due to self-harm, which are indicators of threats to mental well-being. Social inclusion may enhance mental well-being and resilience among autistic people. According to Simplican and colleague's (2015) model of social inclusion for people with intellectual and developmental disabilities, social inclusion is an interaction between community participation and interpersonal relationships. There is limited research on social inclusion that includes the integration of interpersonal relationships and community participation among autistic people or the impact of social inclusion on the well-being of autistic people. Additionally, little evidence exists regarding how autistic people prefer to be included in the community or form interpersonal relationships. OBJECTIVE: The long-term objective of this project is to improve social inclusion factors to support the mental well-being of autistic people. This protocol describes a community-based, mixed methods pilot study to develop a definition of meaningful social inclusion for autistic people and to understand the relationship between meaningful social inclusion and mental well-being among autistic adolescents and emerging adults. METHODS: The project uses a community-based, sequential mixed methods design with a formative phase (Phase 1) that informs a survey phase (Phase 2) and concludes with a process evaluation of the community engagement process (Phase 3). During Phase 1, we will recruit 10 community partners (autistic adults and stakeholders) and conduct sharing sessions to cocreate a definition of meaningful social inclusion and a survey of meaningful social inclusion and well-being. During Phase 2, we will recruit 200 participants (100 autistic adolescents and emerging adults and 100 caregivers) to complete the survey. We will examine whether meaningful social inclusion predicts well-being given sociodemographic factors using ordered logistic regression, with well-being categorized as low, medium, and high. During Phase 3, the community partners from Phase 1 will complete a survey on their experiences with the project. RESULTS: Ethics approval was obtained for this project in March 2023. We have recruited community partners and started the Phase 1 focus groups as of September 2023. Phase 2 and Phase 3 have not yet started. We expect to complete this study by March 2025. CONCLUSIONS: Using a community-based, mixed methods approach, we intended to develop a definition of meaningful social inclusion for autistic people and understand the role meaningful social inclusion plays in the well-being of autistic people. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/52658.

2.
ACS Omega ; 8(42): 39616-39624, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37901495

RESUMO

Accurate and cost-effective methods for the analysis of oxychlorine compounds in water are critical to modern chlorine-based water treatment. With alternatives to elemental chlorine and hypochlorite bleaches growing in popularity, simple quantification methods for the disinfectant chlorine dioxide (ClO2) in water, as well as chlorite (ClO2-) and chlorate (ClO3-), which are commonly used precursors in ClO2 generation, are required. However, currently, regulated standard methods require specialized equipment and do not effectively discriminate between molecular and ionic species. In this contribution, we present a simple titration-based method for chlorite determination in water using commercially available and easy-to-handle reagents. Specifically, chlorite is reduced with a slight excess of thioureadioxide (TUD). The remaining reductant is then back-titrated against a known amount of potassium permanganate, affording calculatable chlorite concentrations through measured consumption of a reductant and a clear visual endpoint upon accumulation of excess KMnO4. Straightforward methods for chlorite standardization with reasonable error and accuracy for field and/or lab application have the potential to greatly enhance quality assurance and therefore assist in resource deployment in water treatment.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37113206

RESUMO

Objective: To evaluate the impact of a diagnostic stewardship intervention on Clostridioides difficile healthcare-associated infections (HAI). Design: Quality improvement study. Setting: Two urban acute care hospitals. Interventions: All inpatient stool testing for C. difficile required review and approval prior to specimen processing in the laboratory. An infection preventionist reviewed all orders daily through chart review and conversations with nursing; orders meeting clinical criteria for testing were approved, orders not meeting clinical criteria were discussed with the ordering provider. The proportion of completed tests meeting clinical criteria for testing and the primary outcome of C. difficile HAI were compared before and after the intervention. Results: The frequency of completed C. difficile orders not meeting criteria was lower [146 (7.5%) of 1,958] in the intervention period (January 10, 2022-October 14, 2022) than in the sampled 3-month preintervention period [26 (21.0%) of 124; P < .001]. C. difficile HAI rates were 8.80 per 10,000 patient days prior to the intervention (March 1, 2021-January 9, 2022) and 7.69 per 10,000 patient days during the intervention period (incidence rate ratio, 0.87; 95% confidence interval, 0.73-1.05; P = .13). Conclusions: A stringent order-approval process reduced clinically nonindicated testing for C. difficile but did not significantly decrease HAIs.

4.
Am J Infect Control ; 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37116712

RESUMO

BACKGROUND: Mobile ultraviolet (UV) disinfection uses UV-C light to render microorganisms nonviable and reduce environmental transmission of pathogens in hospital settings. Optimal strategies for deployment must consider the cost, physical layout, and staffing resources. The aim of this quality improvement study was to increase UV disinfection utilization by developing novel deployment strategies without adding resources. METHODS: A novel deployment strategy and tools were developed by a multidisciplinary group that included infection prevention, environmental services, and nursing unit staff. Utilization was tracked via a manufacturer-supported database. The infection prevention team analyzed the weekly UV disinfection minutes, cycles, and proportions of cycles completed in defined areas across 4 periods: baseline, pilot, baseline 2, and intervention. RESULTS: The median (range) disinfection cycle times per week during a geographically confined pilot (4,985 minutes [3,476-6,551] minutes) and the intervention period (1,454 [512-3,085] minutes) were lower than either baseline period (5,394 [3,953-6,987] and 6,641 [2,830-7,276] minutes, respectively). Cycles per week were lower in the intervention period than in the preceding 3 periods. CONCLUSIONS: Use of UV disinfection in acute care settings should be guided by multidisciplinary groups balancing resources against efficacy and using tailored tools to promote efficiency.

5.
Infect Control Hosp Epidemiol ; 44(9): 1485-1489, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36645014

RESUMO

OBJECTIVE: To evaluate variables that affect risk of contamination for endoscopic retrograde cholangiopancreatography and endoscopic ultrasound endoscopes. DESIGN: Observational, quality improvement study. SETTING: University medical center with a gastrointestinal endoscopy service performing ∼1,000 endoscopic retrograde cholangiopancreatography and ∼1,000 endoscopic ultrasound endoscope procedures annually. METHODS: Duodenoscope and linear echoendoscope sampling (from the elevator mechanism and instrument channel) was performed from June 2020 through September 2021. Operational changes during this period included standard reprocessing with high-level disinfection with ethylene oxide gas sterilization (HLD-ETO) was switched to double high-level disinfection (dHLD) (June 16, 2020-July 15, 2020), and duodenoscopes changed to disposable tip model (March 2021). The frequency of contamination for the co-primary outcomes were characterized by calculated risk ratios. RESULTS: The overall pathogenic contamination rate was 4.72% (6 of 127). Compared to duodenoscopes, linear echoendoscopes had a contamination risk ratio of 3.64 (95% confidence interval [CI], 0.69-19.1). Reprocessing using HLD-ETO was associated with a contamination risk ratio of 0.29 (95% CI, 0.06-1.54). Linear echoendoscopes undergoing dHLD had the highest risk of contamination (2 of 18, 11.1%), and duodenoscopes undergoing HLD-ETO and the lowest risk of contamination (0 of 53, 0%). Duodenoscopes with a disposable tip had a 0% contamination rate (0 of 27). CONCLUSIONS: We did not detect a significant reduction in endoscope contamination using HLD-ETO versus dHLD reprocessing. Linear echoendoscopes have a risk of contamination similar to that of duodenoscopes. Disposable tips may reduce the risk of duodenoscope contamination.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Desinfecção , Humanos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Desinfecção/métodos , Duodenoscópios , Endossonografia , Contaminação de Equipamentos/prevenção & controle
6.
J Clin Med ; 9(11)2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33227912

RESUMO

To investigate whether high glucose (HG) alters Rab20 expression and compromises gap junction intercellular communication (GJIC) and cell survival, retinal cells were studied for altered intracellular trafficking of connexin 43 (Cx43). Retinal endothelial cells (RRECs) and retinal Müller cells (rMCs) were grown in normal (N; 5 mM glucose) or HG (30 mM glucose) medium for seven days. In parallel, cells grown in HG medium were transfected with either Rab20 siRNA or scrambled siRNA as a control. Rab20 and Cx43 expression and their localization and distribution were assessed using Western Blot and immunostaining, respectively. Changes in GJIC activity were assessed using scrape load dye transfer, and apoptosis was identified using differential dye staining assay. In RRECs or rMCs grown in HG medium, Rab20 expression was significantly increased concomitant with a decreased number of Cx43 plaques. Importantly, a significant increase in the number of Cx43 plaques and GJIC activity was observed in cells transfected with Rab20 siRNA. Additionally, Rab20 downregulation inhibited HG-induced apoptosis in RRECs and rMCs. Results indicate HG-mediated Rab20 upregulation decreases Cx43 localization at the cell surface, resulting in compromised GJIC activity. Reducing Rab20 expression could be a useful strategy in preventing HG-induced vascular and Müller cell death associated with diabetic retinopathy.

7.
Clin Podiatr Med Surg ; 36(4): 563-576, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31466568

RESUMO

Amnion and chorion products show great promise and have real potential to be mainstays of treatment for chronic, nonhealing wounds. Although amniotic products do carry a cost, the decrease in time to healing, with the assumed subsequent decrease in complication and infection rates, should also be taken into consideration. These products, with their unique biologic potential and availability in the clinical setting, may prove to be beneficial in a vast array of podiatric surgical applications.


Assuntos
Âmnio/transplante , Traumatismos do Tornozelo/terapia , Córion/transplante , Traumatismos do Pé/terapia , Podiatria , Cicatrização , Aloenxertos , Humanos
8.
Mol Vis ; 23: 318-333, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28659708

RESUMO

PURPOSE: A region within chromosome 10q26 has a set of single nucleotide polymorphisms (SNPs) that define a haplotype that confers high risk for age-related macular degeneration (AMD). We used a bioinformatics approach to search for genes in this region that may be responsible for risk for AMD by assessing levels of gene expression in individuals carrying different haplotypes and by searching for open chromatin regions in the retinal pigment epithelium (RPE) that might include one or more of the SNPs. METHODS: We surveyed the PubMed and the 1000 Genomes databases to find all common (minor allele frequency > 0.01) SNPs in 10q26 strongly associated with AMD. We used the HaploReg and LDlink databases to find sets of SNPs with alleles in linkage disequilibrium and used the Genotype-Tissue Expression (GTEx) database to search for correlations between genotypes at individual SNPs and the relative level of expression of the genes. We also accessed Encyclopedia of DNA Elements (ENCODE) to find segments of open chromatin in the region with the AMD-associated SNPs. Predicted transcription factor binding motifs were identified using HOMER, PROMO, and RegulomeDB software programs. RESULTS: There are 34 polymorphisms within a 30-kb region that are in strong linkage disequilibrium (r2>0.8) with the reference SNP rs10490924 previously associated with risk for AMD. The expression of three genes in this region, PLEKHA1, ARMS2, and HTRA1 varies between people who have the low-AMD-risk haplotype compared with those with the high-AMD-risk haplotype. For PLEKHA1, 44 tissues have an expression pattern with the high-AMD-risk haplotype associated with low expression (rs10490924 effect size -0.43, p = 3.8 x 10-5 in ovary). With regard to ARMS2, the variation is most pronounced in testes: homozygotes with the high-AMD-risk haplotype express ARMS2 at lower levels than homozygotes with the low-AMD-risk haplotype; expression in heterozygotes falls in between (rs10490924 effect size -0.79, p = 7.5 x 10-24). For HTRA1, the expression pattern is the opposite; the high-AMD-risk haplotype has higher levels of expression in 27 tissues (rs10490924 effect size 0.40, p = 1.5 × 10-7 in testes). None of the other 22 genes within one megabase of rs10490924, or any gene in the entire genome, have mRNA expression levels that correlate with the high-AMD-risk haplotype. More than 100 other SNPs in the 10q26 region affect the expression of PLEKHA1 and ARMS2 but not that of HTRA1; none of these SNPs affects the risk for AMD according to published genome-wide association studies (GWASs). Two of the AMD-risk SNPs (rs36212732 and rs36212733) affect transcription factor binding sites in proximity to a DNase I hypersensitive region (i.e., a region of open chromatin) in RPE cells. CONCLUSIONS: SNPs in chromosome 10q26 that influence the expression of only PLEKHA1 or ARMS2 are not associated with risk for AMD, while most SNPs that influence the expression of HTRA1 are associated with risk for AMD. Two of the AMD-risk SNPs affect transcription factor binding sites that may control expression of one of the linked genes in the RPE. These findings suggest that the variation in the risk for AMD associated with chromosome 10q26 is likely due to variation in HTRA1 expression. Modulating HTRA1 activity might be a potential therapy for AMD.


Assuntos
Cromossomos Humanos Par 10/genética , Regulação da Expressão Gênica , Predisposição Genética para Doença , Haplótipos/genética , Serina Peptidase 1 de Requerimento de Alta Temperatura A/genética , Degeneração Macular/genética , Adulto , Alelos , Sequência de Bases , Sítios de Ligação/genética , Feminino , Heterozigoto , Serina Peptidase 1 de Requerimento de Alta Temperatura A/metabolismo , Homozigoto , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Desequilíbrio de Ligação/genética , Masculino , Proteínas de Membrana/genética , Ovário/metabolismo , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Fatores de Risco , Testículo/metabolismo , Fatores de Transcrição/metabolismo
9.
Am J Reprod Immunol ; 71(1): 34-43, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23902376

RESUMO

PROBLEM: Clostridium sordellii causes endometrial infections, but little is known regarding host defenses against this pathogen. METHOD OF STUDY: We tested the hypothesis that the immunoregulatory lipid prostaglandin (PG) E2 suppresses human macrophage clearance of C. sordellii through receptor-induced increases in intracellular cyclic adenosine monophosphate (cAMP). The THP-1 macrophage cell line was used to quantify C. sordellii phagocytosis. RESULTS: PGE2 increased cAMP levels, activated protein kinase A (PKA), and inhibited the class A scavenger receptor-dependent phagocytosis of C. sordellii. Activation of the EP2 and EP4 receptors increased intracellular cAMP and inhibited phagocytosis, with evidence favoring a more important role for EP4 over EP2. This was supported by EP receptor expression data and the use of pharmacological receptor antagonists. In addition, the PKA isoform RI appeared to be more important than RII in mediating the suppression of ingestion of C. sordellii. CONCLUSION: The endogenous lipid mediator PGE2 impairs human innate immune responses against C. sordellii.


Assuntos
Infecções por Clostridium/imunologia , Clostridium sordellii/imunologia , Macrófagos/imunologia , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Linhagem Celular , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dinoprostona/imunologia , Humanos , Tolerância Imunológica , Imunidade Inata , Fagocitose , Isoformas de Proteínas/metabolismo
10.
J Occup Environ Med ; 55(12 Suppl): S8-11, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24284752

RESUMO

OBJECTIVE: The objective of this article was to provide an overview of the National Institute for Occupational Safety and Health (NIOSH) Total Worker Health™ (TWH™) Program that was launched by the institute in 2011. METHODS: This article describes the TWH™ concept, relevant issues, and the NIOSH Program. Examples of the concept are provided. RESULTS: Total Worker Health™ is a strategy integrating occupational safety and health protection with health promotion to prevent worker injury and illness and to advance health and well-being. CONCLUSIONS: The NIOSH TWH™ Program responds to demands for information and practical solutions to the health, safety, and well-being challenges that workers and their employers face. It also addresses issues related to the nation's need to sustain a globally competitive workforce.


Assuntos
Promoção da Saúde , National Institute for Occupational Safety and Health, U.S. , Saúde Ocupacional , Comportamento Cooperativo , Promoção da Saúde/organização & administração , Humanos , Liderança , Estados Unidos
11.
Prostaglandins Other Lipid Mediat ; 98(1-2): 23-30, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22575745

RESUMO

Pneumonia is a major global health problem. Prostaglandin (PG) E(2) is an immunomodulatory lipid with anti-inflammatory, immunosuppressive, and pro-resolving actions. Data suggest that the E-prostanoid (EP) 2 receptor mediates immunomodulatory effects of PGE(2), but the extent to which this occurs in Streptococcus pneumoniae infection is unknown. Intratracheal lung infection of C57BL/6 mice possessing (EP2(+/+)) or lacking (EP2(-/-)) the EP2 receptor was performed, as were in vitro studies of alveolar macrophage (AM) host defense functions. Bacterial clearance and survival were significantly improved in vivo in EP2(-/-) mice and it correlated with greater neutrophilic inflammation and higher lung IL-12 levels. Upon ex vivo challenge with pneumococcus, EP2(-/-)cells expressed greater amounts of TNF-α and MIP-2 than did EP2(+/+) AMs, and had improved phagocytosis, intracellular killing, and reactive oxygen intermediate generation. These data suggest that PGE(2)-EP2 signaling may provide a novel pharmacological target for treating pneumococcal pneumonia in combination with antimicrobials.


Assuntos
Imunidade Inata/imunologia , Receptores de Prostaglandina E/metabolismo , Streptococcus pneumoniae/imunologia , Animais , Feminino , Imunidade Inata/genética , Interleucina-12/metabolismo , Camundongos , Camundongos Mutantes , Infecções Pneumocócicas/imunologia , Espécies Reativas de Oxigênio/metabolismo , Receptores de Prostaglandina E/genética , Fator de Necrose Tumoral alfa/metabolismo
12.
Sci Signal ; 5(210): ra12, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22317922

RESUMO

Macrophage ingestion of the yeast Candida albicans requires its recognition by multiple receptors and the activation of diverse signaling programs. Synthesis of the lipid mediator prostaglandin E(2) (PGE(2)) and generation of cyclic adenosine monophosphate (cAMP) also accompany this process. Here, we characterized the mechanisms underlying PGE(2)-mediated inhibition of phagocytosis and filamentous actin (F-actin) polymerization in response to ingestion of C. albicans by alveolar macrophages. PGE(2) suppressed phagocytosis and F-actin formation through the PGE(2) receptors EP2 and EP4, cAMP, and activation of types I and II protein kinase A. Dephosphorylation and activation of the actin depolymerizing factor cofilin-1 were necessary for these inhibitory effects of PGE(2). PGE(2)-dependent activation of cofilin-1 was mediated by the protein phosphatase activity of PTEN (phosphatase and tensin homolog deleted on chromosome 10), with which it directly associated. Because enhanced production of PGE(2) accompanies many immunosuppressed states, the PTEN-dependent pathway described here may contribute to impaired antifungal defenses.


Assuntos
Candida albicans/imunologia , Candidíase/imunologia , Cofilina 1/imunologia , Dinoprostona/imunologia , Tolerância Imunológica , Macrófagos Alveolares/imunologia , PTEN Fosfo-Hidrolase/imunologia , Fagocitose/imunologia , Actinas/imunologia , Actinas/metabolismo , Animais , Candida albicans/metabolismo , Candidíase/metabolismo , Células Cultivadas , Cofilina 1/metabolismo , AMP Cíclico/imunologia , AMP Cíclico/metabolismo , Proteína Quinase Tipo I Dependente de AMP Cíclico/imunologia , Proteína Quinase Tipo I Dependente de AMP Cíclico/metabolismo , Proteína Quinase Tipo II Dependente de AMP Cíclico/imunologia , Proteína Quinase Tipo II Dependente de AMP Cíclico/metabolismo , Dinoprostona/biossíntese , Feminino , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/microbiologia , PTEN Fosfo-Hidrolase/metabolismo , Fosforilação/imunologia , Ratos , Ratos Wistar , Receptores de Prostaglandina E Subtipo EP2/imunologia , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Receptores de Prostaglandina E Subtipo EP4/imunologia , Receptores de Prostaglandina E Subtipo EP4/metabolismo
13.
J Biol Chem ; 286(33): 28902-28913, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21715328

RESUMO

Candida albicans is the most common opportunistic fungal pathogen and causes local and systemic disease in immunocompromised patients. Alveolar macrophages (AMs) are pivotal for the clearance of C. albicans from the lung. Activated AMs secrete 5-lipoxygenase-derived leukotrienes (LTs), which in turn enhance phagocytosis and microbicidal activity against a diverse array of pathogens. Our aim was to investigate the role of LTB(4) and LTD(4) in AM antimicrobial functions against C. albicans and the signaling pathways involved. Pharmacologic and genetic inhibition of LT biosynthesis as well as receptor antagonism reduced phagocytosis of C. albicans when compared with untreated or WT controls. Conversely, exogenous LTs of both classes augmented base-line C. albicans phagocytosis by AMs. Although LTB(4) enhanced mainly mannose receptor-dependent fungal ingestion, LTD(4) enhanced mainly dectin-1 receptor-mediated phagocytosis. LT enhancement of yeast ingestion was dependent on protein kinase C-δ (PKCδ) and PI3K but not PKCα and MAPK activation. Both LTs reduced activation of cofilin-1, whereas they enhanced total cellular F-actin; however, LTB(4) accomplished this through the activation of LIM kinases (LIMKs) 1 and 2, whereas LTD(4) did so exclusively via LIMK-2. Finally, both exogenous LTB(4) and LTD(4) enhanced AM fungicidal activity in an NADPH oxidase-dependent manner. Our data identify LTB(4) and LTD(4) as key mediators of innate immunity against C. albicans, which act by both distinct and conserved signaling mechanisms to enhance multiple antimicrobial functions of AMs.


Assuntos
Actinas/metabolismo , Candida albicans/metabolismo , Candidíase/metabolismo , Cofilina 1/metabolismo , Imunidade Inata/fisiologia , Leucotrieno B4/metabolismo , Macrófagos Alveolares/metabolismo , Actinas/genética , Actinas/imunologia , Animais , Candida albicans/imunologia , Candidíase/genética , Candidíase/imunologia , Cofilina 1/genética , Cofilina 1/imunologia , Ativação Enzimática/genética , Ativação Enzimática/imunologia , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/imunologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Lectinas Tipo C , Leucotrieno B4/genética , Leucotrieno B4/imunologia , Quinases Lim/genética , Quinases Lim/imunologia , Quinases Lim/metabolismo , Macrófagos Alveolares/imunologia , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/imunologia , Proteínas do Tecido Nervoso/metabolismo , Fagocitose/genética , Fagocitose/imunologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/imunologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteína Quinase C-delta , Ratos , Ratos Wistar
14.
J Clin Invest ; 121(2): 671-82, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21206089

RESUMO

Activation of NF-κB and 5-lipoxygenase-mediated (5-LO-mediated) biosynthesis of the lipid mediator leukotriene B4 (LTB4) are pivotal components of host defense and inflammatory responses. However, the role of LTB4 in mediating innate immune responses elicited by specific TLR ligands and cytokines is unknown. Here we have shown that responses dependent on MyD88 (an adaptor protein that mediates signaling through all of the known TLRs, except TLR3, as well as IL-1ß and IL-18) are reduced in mice lacking either 5-LO or the LTB4 receptor BTL1, and that macrophages from these mice are impaired in MyD88-dependent activation of NF-κB. This macrophage defect was associated with lower basal and inducible expression of MyD88 and reflected impaired activation of STAT1 and overexpression of the STAT1 inhibitor SOCS1. Expression of MyD88 and responsiveness to the TLR4 ligand LPS were decreased by Stat1 siRNA silencing in WT macrophages and restored by Socs1 siRNA in 5-LO-deficient macrophages. These results uncover a pivotal role in macrophages for the GPCR BLT1 in regulating activation of NF-κB through Stat1-dependent expression of MyD88.


Assuntos
Leucotrieno B4/imunologia , Macrófagos/imunologia , Fator 88 de Diferenciação Mieloide/imunologia , NF-kappa B/imunologia , Proteínas Supressoras da Sinalização de Citocina/imunologia , Animais , Araquidonato 5-Lipoxigenase/imunologia , Quimiocina CCL5/imunologia , Feminino , Inativação Gênica , Imunidade Inata/imunologia , Interleucina-6/imunologia , Janus Quinase 2/metabolismo , Lipopolissacarídeos/imunologia , Macrófagos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Interferência de RNA , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/imunologia , Transdução de Sinais/imunologia , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/genética
15.
Infect Immun ; 78(5): 2264-71, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20231413

RESUMO

Leukotriene B(4) (LTB(4)) is a potent lipid mediator of inflammation formed by the 5-lipoxygenase (5-LO)-catalyzed oxidation of arachidonic acid. We have previously shown that (i) LTB(4) is generated during infection, (ii) its biosynthesis is essential for optimal antimicrobial host defense, (iii) LT deficiency is associated with clinical states of immunocompromise, and (iv) exogenous LTB(4) augments antimicrobial functions in phagocytes. Here, we sought to determine whether the administration of LTB(4) has therapeutic potential in a mouse model of pneumonia. Wild-type and 5-LO knockout mice were challenged with Streptococcus pneumoniae via the intranasal route, and bacterial burdens, leukocyte counts, and cytokine levels were determined. LTB(4) was administered via the intraperitoneal, intravenous, and intranasal routes prior to pneumococcal infection and by aerosol 24 h following infection. Leukocytes recovered from mice given S. pneumoniae and treated with aerosolized LTB(4) were evaluated for expression levels of the p47phox subunit of NADPH oxidase. Intrapulmonary but not systemic pretreatment with LTB(4) significantly reduced the lung S. pneumoniae burden in wild-type mice. Aerosolized LTB(4) was effective at improving lung bacterial clearance when administered postinoculation in animals with established infection and exhibited greater potency in 5-LO knockout animals, which also exhibited greater baseline susceptibility. Augmented bacterial clearance in response to LTB(4) was associated with enhanced monocyte recruitment and leukocyte expression of p47phox. The results of the current study in an animal model serve as a proof of concept for the potential utility of treatment with aerosolized LTB(4) as an immunostimulatory strategy in patients with bacterial pneumonia.


Assuntos
Produtos Biológicos/administração & dosagem , Fatores Imunológicos/administração & dosagem , Leucotrieno B4/administração & dosagem , Pneumonia Pneumocócica/tratamento farmacológico , Streptococcus pneumoniae/imunologia , Administração por Inalação , Aerossóis/administração & dosagem , Animais , Araquidonato 5-Lipoxigenase/deficiência , Contagem de Colônia Microbiana , Citocinas/análise , Injeções Intraperitoneais , Injeções Intravenosas , Contagem de Leucócitos , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Knockout , Pneumonia Pneumocócica/imunologia
16.
J Immunol ; 183(4): 2642-9, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19635910

RESUMO

Prostaglandins (PGs) are potent lipid mediators that are produced during infections and whose synthesis and signaling networks present potential pharmacologic targets for immunomodulation. PGE(2) acts through the ligation of four distinct G protein-coupled receptors, E-prostanoid (EP) 1-4. Previous in vitro and in vivo studies demonstrated that the activation of the G(alphas)-coupled EP2 and EP4 receptors suppresses inflammatory responses to microbial pathogens through cAMP-dependent signaling cascades. Although it is speculated that PGE(2) signaling via the G(alphai)-coupled EP3 receptor might counteract EP2/EP4 immunosuppression in the context of bacterial infection (or severe inflammation), this has not previously been tested in vivo. To address this, we infected wild-type (EP3(+/+)) and EP3(-/-) mice with the important respiratory pathogen Streptococcus pneumoniae or injected mice i.p. with LPS. Unexpectedly, we observed that EP3(-/-) mice were protected from mortality after infection or LPS. The enhanced survival observed in the infected EP3(-/-) mice correlated with enhanced pulmonary clearance of bacteria; reduced accumulation of lung neutrophils; lower numbers of circulating blood leukocytes; and an impaired febrile response to infection. In vitro studies revealed improved alveolar macrophage phagocytic and bactericidal capacities in EP3(-/-) cells that were associated with an increased capacity to generate NO in response to immune stimulation. Our studies underscore the complex nature of PGE(2) immunomodulation in the context of host-microbial interactions in the lung. Pharmacological targeting of the PGE(2)-EP3 axis represents a novel area warranting greater investigative interest in the prevention and/or treatment of infectious diseases.


Assuntos
Alprostadil/análogos & derivados , Imunidade Inata , Pneumonia Pneumocócica/imunologia , Pneumonia Pneumocócica/mortalidade , Receptores de Prostaglandina E/deficiência , Receptores de Prostaglandina E/genética , Alprostadil/metabolismo , Alprostadil/fisiologia , Animais , Dinoprostona/fisiologia , Feminino , Imunidade Inata/genética , Mediadores da Inflamação/administração & dosagem , Mediadores da Inflamação/antagonistas & inibidores , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/antagonistas & inibidores , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pneumonia Pneumocócica/patologia , Receptores de Prostaglandina E/fisiologia , Receptores de Prostaglandina E Subtipo EP3 , Índice de Gravidade de Doença , Transdução de Sinais/genética , Transdução de Sinais/imunologia
17.
J Immunol ; 180(12): 8222-30, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18523288

RESUMO

Fatal cases of acute shock complicating Clostridium sordellii endometritis following medical abortion with mifepristone (also known as RU-486) used with misoprostol were reported. The pathogenesis of this unexpected complication remains enigmatic. Misoprostol is a pharmacomimetic of PGE(2), an endogenous suppressor of innate immunity. Clinical C. sordellii infections were associated with intravaginal misoprostol administration, suggesting that high misoprostol concentrations within the uterus impair immune responses against C. sordellii. We modeled C. sordellii endometritis in rats to test this hypothesis. The intrauterine but not the intragastric delivery of misoprostol significantly worsened mortality from C. sordellii uterine infection, and impaired bacterial clearance in vivo. Misoprostol also reduced TNF-alpha production within the uterus during infection. The intrauterine injection of misoprostol did not enhance mortality from infection by the vaginal commensal bacterium Lactobacillus crispatus. In vitro, misoprostol suppressed macrophage TNF-alpha and chemokine generation following C. sordellii or peptidoglycan challenge, impaired leukocyte phagocytosis of C. sordellii, and inhibited uterine epithelial cell human beta-defensin expression. These immunosuppressive effects of misoprostol, which were not shared by mifepristone, correlated with the activation of the G(s) protein-coupled E prostanoid (EP) receptors EP2 and EP4 (macrophages) or EP4 alone (uterine epithelial cells). Our data provide a novel explanation for postabortion sepsis leading to death and also suggest that PGE(2), in which production is exaggerated within the reproductive tract during pregnancy, might be an important causal determinant in the pathogenesis of more common infections of the gravid uterus.


Assuntos
Infecções por Clostridium/imunologia , Clostridium sordellii/efeitos dos fármacos , Clostridium sordellii/imunologia , Modelos Animais de Doenças , Endometrite/imunologia , Endometrite/microbiologia , Imunidade Inata/efeitos dos fármacos , Misoprostol/efeitos adversos , Animais , Linhagem Celular , Clostridium sordellii/patogenicidade , Endometrite/mortalidade , Feminino , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/fisiologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos CBA , Misoprostol/administração & dosagem , Ratos , Ratos Wistar , Virulência/efeitos dos fármacos , Virulência/imunologia
18.
J Virol ; 81(3): 1241-50, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17108043

RESUMO

Innate inflammatory events promoting antiviral defense in the liver against murine cytomegalovirus (MCMV) infection have been characterized. However, the mechanisms that regulate the selective recruitment of inflammatory T lymphocytes to the liver during MCMV infection have not been defined. The studies presented here demonstrate the expression of monokine induced by gamma interferon (IFN-gamma; Mig/CXCL9) and IFN-gamma-inducible protein 10 (IP-10/CXCL10) in liver leukocytes and correlate their production with the infiltration of MCMV-specific CD8 T cells into the liver. Antibody-mediated neutralization of CXCL9 and CXCL10 and studies using mice deficient in CXCR3, the primary known receptor for these chemokines, revealed that CXCR3-dependent mechanisms promote the infiltration of virus-specific CD8 T cells into the liver during acute infection with MCMV. Furthermore, CXCR3 functions augmented the hepatic accumulation of CD8 T-cell IFN-gamma responses to MCMV. Evaluation of protective functions demonstrated enhanced pathology that overlapped with transient increases in virus titers in CXCR3-deficient mice. However, ultimate viral clearance and survival were not compromised. Thus, CXCR3-mediated signals support the accumulation of MCMV-specific CD8 T cells that contribute to, but are not exclusively required for, protective responses in a virus-infected tissue site.


Assuntos
Infecções por Citomegalovirus/imunologia , Ativação Linfocitária , Muromegalovirus/imunologia , Receptores de Quimiocinas/biossíntese , Linfócitos T/imunologia , Animais , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Muromegalovirus/efeitos dos fármacos , Muromegalovirus/crescimento & desenvolvimento , Receptores CXCR3 , Linfócitos T/metabolismo
19.
J Trauma ; 58(3): 561-70, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15761352

RESUMO

BACKGROUND: Substance abuse is associated with injuries, but these associations have not been well characterized by type of substance and injury type. METHODS: A cross-sectional study of patients selected for toxicology screening compared those with positive and those with negative test results for drugs and alcohol. RESULTS: Patients with positive alcohol toxicology results were more likely to have violence-related and penetrating injuries than patients with negative results. However, after adjustment for positive cocaine toxicology results, the association between alcohol and penetrating injury was no longer significant. Positive test results for any drug were not associated with any specific injury type, but cocaine was independently associated with violence-related injury. The associations of alcohol and cocaine with violence-related injury appear to be additive. In contrast, opiates were independently associated with nonviolent injuries and burns. CONCLUSIONS: Alcohol and cocaine use is independently associated with violence-related injuries, whereas opiate use is independently associated with nonviolent injuries and burns.


Assuntos
Hospitalização/estatística & dados numéricos , Programas de Rastreamento/métodos , Detecção do Abuso de Substâncias/métodos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Ferimentos e Lesões/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Causalidade , Comorbidade , Estudos Transversais , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Meio-Oeste dos Estados Unidos/epidemiologia , Avaliação das Necessidades , Razão de Chances , Sistema de Registros , Transtornos Relacionados ao Uso de Substâncias/complicações , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Tomografia Computadorizada por Raios X , Centros de Traumatologia , Violência/estatística & dados numéricos , Ferimentos e Lesões/complicações
20.
J Clin Invest ; 110(3): 321-30, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12163451

RESUMO

Macrophage inflammatory protein 1alpha (MIP-1alpha, CCL3) is critical for liver NK cell inflammation and delivery of IFN-gamma to mediate downstream protective responses against murine cytomegalovirus (MCMV) infections. This system was used to evaluate the upstream contribution of the type 1 IFNs, IFN-alpha/beta, in promotion of MIP-1alpha production. Mice deficient in IFN-alpha/beta functions, as a result of mutation in the receptor for these cytokines (IFN-alpha/betaR(-)), were profoundly deficient in MIP-1alpha expression and accumulation of NK cells and macrophages in the liver and had increased sensitivity to MCMV infection. The cytokines themselves were responsible for the immunoregulatory effects, since administration of recombinant IFN-alpha (rIFN-alpha) to immunocompetent mice also induced these changes. IFN-alpha/beta was required for NK cell accumulation during infection, and MIP-1alpha was required for NK cell accumulation in response to administered rIFN-alpha. In vivo trafficking assays demonstrated a requirement for IFN-alpha/betaR signaling for leukocyte localization in, and delivery of MIP-1alpha-producing macrophages to, the liver. These results extend characterization of the cytokine and chemokine cascade required for protection against viral infections in tissues by defining IFN-alpha/beta-dependent mechanisms promoting MIP-1alpha production and the resulting hepatic accumulation of NK cells.


Assuntos
Interferon-alfa/imunologia , Interferon beta/imunologia , Células Matadoras Naturais/imunologia , Fígado/imunologia , Proteínas Inflamatórias de Macrófagos/imunologia , Macrófagos/imunologia , Animais , Transporte Biológico , Movimento Celular , Quimiocina CCL3 , Quimiocina CCL4 , Feminino , Infecções por Herpesviridae/imunologia , Humanos , Interferon Tipo I/administração & dosagem , Interferon Tipo I/imunologia , Interferon-alfa/biossíntese , Interferon beta/biossíntese , Células Matadoras Naturais/citologia , Fígado/patologia , Proteínas Inflamatórias de Macrófagos/biossíntese , Proteínas Inflamatórias de Macrófagos/genética , Macrófagos/citologia , Masculino , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Muromegalovirus/imunologia , Receptor de Interferon alfa e beta , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...