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1.
Cell ; 164(1-2): 246-257, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26771494

RESUMO

Intercellular communication between parasites and with host cells provides mechanisms for parasite development, immune evasion, and disease pathology. Bloodstream African trypanosomes produce membranous nanotubes that originate from the flagellar membrane and disassociate into free extracellular vesicles (EVs). Trypanosome EVs contain several flagellar proteins that contribute to virulence, and Trypanosoma brucei rhodesiense EVs contain the serum resistance-associated protein (SRA) necessary for human infectivity. T. b. rhodesiense EVs transfer SRA to non-human infectious trypanosomes, allowing evasion of human innate immunity. Trypanosome EVs can also fuse with mammalian erythrocytes, resulting in rapid erythrocyte clearance and anemia. These data indicate that trypanosome EVs are organelles mediating non-hereditary virulence factor transfer and causing host erythrocyte remodeling, inducing anemia.


Assuntos
Vesículas Extracelulares/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Protozoários/metabolismo , Trypanosoma brucei rhodesiense/citologia , Trypanosoma brucei rhodesiense/imunologia , Tripanossomíase Africana/patologia , Tripanossomíase Africana/parasitologia , Fatores de Virulência/metabolismo , Anemia/patologia , Animais , Eritrócitos/parasitologia , Flagelos/metabolismo , Humanos , Evasão da Resposta Imune , Camundongos , Proteoma/metabolismo , Rodaminas/análise , Trypanosoma brucei rhodesiense/metabolismo , Trypanosoma brucei rhodesiense/patogenicidade
2.
Immunol Cell Biol ; 98(1): 12-21, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31742781

RESUMO

Acute rheumatic fever (ARF) and chronic rheumatic heart disease (RHD) are autoimmune sequelae of a Group A streptococcal infection with significant global mortality and poorly understood pathogenesis. Immunoglobulin and complement deposition were observed in ARF/RHD valve tissue over 50 years ago, yet contemporary investigations have been lacking. This study applied systems immunology to investigate the relationships between the complement system and immunoglobulin in ARF. Patients were stratified by C-reactive protein (CRP) concentration into high (≥10 µg mL-1 ) and low (<10 µg mL-1 ) groups to distinguish those with clinically significant inflammatory processes from those with abating inflammation. The circulating concentrations of 17 complement factors and six immunoglobulin isotypes and subclasses were measured in ARF patients and highly matched healthy controls using multiplex bead-based immunoassays. An integrative statistical approach combining feature selection and principal component analysis revealed a linked IgG3-C4 response in ARF patients with high CRP that was absent in controls. Strikingly, both IgG3 and C4 were elevated above clinical reference ranges, suggesting these features are a marker of ARF-associated inflammation. Humoral immunity in response to M protein, an antigen implicated in ARF pathogenesis, was completely polarized to IgG3 in the patient group. Furthermore, the anti-M-protein IgG3 response was correlated with circulating IgG3 concentration, highlighting a potential role for this potent immunoglobulin subclass in disease. In conclusion, a linked IgG3-C4 response appears important in the initial, inflammatory stage of ARF and may have immediate utility as a clinical biomarker given the lack of specific diagnostic tests currently available.


Assuntos
Complemento C4 , Imunidade Humoral , Imunoglobulina G , Febre Reumática , Adolescente , Criança , Complemento C4/imunologia , Complemento C4/metabolismo , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Febre Reumática/sangue , Febre Reumática/imunologia
3.
Circulation ; 138(23): 2648-2661, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30571257

RESUMO

BACKGROUND: Acute rheumatic fever (ARF) and rheumatic heart disease are autoimmune consequences of group A streptococcus infection and remain major causes of cardiovascular morbidity and mortality around the world. Improved treatment has been stymied by gaps in understanding key steps in the immunopathogenesis of ARF and rheumatic heart disease. This study aimed to identify (1) effector T cell cytokine(s) that might be dysregulated in the autoimmune response of patients with ARF by group A streptococcus, and (2) an immunomodulatory agent that suppresses this response and could be clinically translatable to high-risk patients with ARF. METHODS: The immune response to group A streptococcus was analyzed in peripheral blood mononuclear cells from an Australian Aboriginal ARF cohort by a combination of multiplex cytokine array, flow cytometric analysis, and global gene expression analysis by RNA sequencing. The immunomodulatory drug hydroxychloroquine was tested for effects on this response. RESULTS: We found a dysregulated interleukin-1ß-granulocyte-macrophage colony-stimulating factor (GM-CSF) cytokine axis in ARF peripheral blood mononuclear cells exposed to group A streptococcus in vitro, whereby persistent interleukin-1ß production is coupled to overproduction of GM-CSF and selective expansion of CXCR3+CCR4-CCR6- CD4 T cells. CXCR3+CCR4-CCR6- CD4 T cells are the major source of GM-CSF in human CD4 T cells and CXCL10, a CXCR3 ligand and potent T helper 1 chemoattractant, was elevated in sera from patients with ARF. GM-CSF has recently emerged as a key T cell-derived effector cytokine in numerous autoimmune diseases, including myocarditis, and the production of CXCL10 may explain selective trafficking of these cells to the heart. We provide evidence that interleukin-1ß amplifies the expansion of GM-CSF-expressing CD4 T cells, which is effectively suppressed by hydroxychloroquine. RNA sequencing showed shifts in gene expression profiles and differentially expressed genes in peripheral blood mononuclear cells derived from patients at different clinical stages of ARF. CONCLUSIONS: Given the safety profile of hydroxychloroquine and its clinical pedigree in treating autoimmune diseases such as rheumatoid arthritis, where GM-CSF plays a pivotal role, we propose that hydroxychloroquine could be repurposed to reduce the risk of rheumatic heart disease after ARF.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Hidroxicloroquina/farmacologia , Interleucina-1beta/metabolismo , Febre Reumática/patologia , Adolescente , Adulto , Proteína C-Reativa/análise , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular , Criança , Citocinas/análise , Citocinas/genética , Citocinas/metabolismo , Feminino , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Masculino , RNA/química , RNA/isolamento & purificação , RNA/metabolismo , Febre Reumática/metabolismo , Streptococcus pyogenes/imunologia , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo , Adulto Jovem
4.
Hum Mol Genet ; 26(10): 1952-1965, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28334834

RESUMO

Limb Girdle Muscular Dystrophies type 2I (LGMD2I), a recessive autosomal muscular dystrophy, is caused by mutations in the Fukutin Related Protein (FKRP) gene. It has been proposed that FKRP, a ribitol-5-phosphate transferase, is a participant in α-dystroglycan (αDG) glycosylation, which is important to ensure the cell/matrix anchor of muscle fibers. A LGMD2I knock-in mouse model was generated to express the most frequent mutation (L276I) encountered in patients. The expression of FKRP was not altered neither at transcriptional nor at translational levels, but its function was impacted since abnormal glycosylation of αDG was observed. Skeletal muscles were functionally impaired from 2 months of age and a moderate dystrophic pattern was evident starting from 6 months of age. Gene transfer with a rAAV2/9 vector expressing Fkrp restored biochemical defects, corrected the histological abnormalities and improved the resistance to eccentric stress in the mouse model. However, injection of high doses of the vector induced a decrease of αDG glycosylation and laminin binding, even in WT animals. Finally, intravenous injection of the rAAV-Fkrp vector into a dystroglycanopathy mouse model due to Fukutin (Fktn) knock-out indicated a dose-dependent toxicity. These data suggest requirement for a control of FKRP expression in muscles.


Assuntos
Distrofia Muscular do Cíngulo dos Membros/terapia , Proteínas/genética , Proteínas/uso terapêutico , Animais , Modelos Animais de Doenças , Distroglicanas/metabolismo , Expressão Gênica , Regulação da Expressão Gênica/genética , Terapia Genética/métodos , Glicosilação , Camundongos , Camundongos Knockout , Músculo Esquelético/metabolismo , Distrofias Musculares/genética , Distrofia Muscular do Cíngulo dos Membros/genética , Mutação , Pentosefosfatos/metabolismo , Pentosiltransferases , Ligação Proteica , Processamento de Proteína Pós-Traducional , Proteínas/metabolismo , Transferases
5.
Handb Exp Pharmacol ; 254: 399-415, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30701317

RESUMO

Conventional antidepressants increase the efflux of biogenic amine neurotransmitters (the monoamine hypothesis of depression) in the central nervous system (CNS) and are the principle drugs used to treat major depressive disorder (MDD). However, the lack of efficacy in some patients, the slow onset of action, and the side effect profiles of existing antidepressants necessitate the exploration of additional treatment options. The discovery of the nociceptin/orphanin FQ peptide NOP receptor (N/OFQ-NOP receptor) system and its characterization in preclinical biological and pharmacological stress-related conditions supports the potential antidepressant and anti-stress properties of a NOP receptor antagonist for the treatment of neurobehavioral disorders. BTRX-246040 (formerly LY2940094) was designed to test this hypothesis in the clinic. A small clinical proof of concept study demonstrated efficacy of BTRX-246040 in MDD patients. In this study, BTRX-246040 (40 mg, p.o.) significantly reduced negative bias as assessed by the facial recognition test within 1 week of treatment and decreased depression symptoms after 8 weeks. BTRX-246040 also reduced depression symptoms in a second trial with heavy alcohol drinkers. Given the comorbidity of MDD and alcohol use disorder, a compound with such effects in patients could be a valuable addition to the medications available. A proof of concept study showed efficacy of BTRX-246040 in reducing heavy drinking and increasing the probability of abstinence in individuals diagnosed with alcohol dependence. In addition, plasma levels of gamma-glutamyl transferase were decreased by BTRX-246040 compared to placebo control implying improvement in liver function. Collectively, the clinical data reviewed within this chapter suggest that BTRX-264040 functions to normalize dysfunction in reward circuits. The overall efficacy and safety of this compound with a novel mechanism of action are encouraging of further clinical development. BTRX-246040 is currently under development for MDD by BlackThorn Therapeutics.


Assuntos
Alcoolismo , Transtorno Depressivo Maior , Antagonistas de Entorpecentes/uso terapêutico , Peptídeos Opioides/farmacologia , Piranos/uso terapêutico , Compostos de Espiro/uso terapêutico , Alcoolismo/tratamento farmacológico , Humanos , Antagonistas de Entorpecentes/química , Peptídeos Opioides/química , Piranos/farmacologia , Compostos de Espiro/química , Compostos de Espiro/farmacologia
6.
Eur Respir J ; 51(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29301918

RESUMO

Exposure to household air pollution (HAP) from solid fuel combustion affects almost half of the world population. Adverse respiratory outcomes such as respiratory infections, impaired lung growth and chronic obstructive pulmonary disease have been linked to HAP exposure. Solid fuel smoke is a heterogeneous mixture of various gases and particulates. Cell culture and animal studies with controlled exposure conditions and genetic homogeneity provide important insights into HAP mechanisms. Impaired bacterial phagocytosis in exposed human alveolar macrophages possibly mediates several HAP-related health effects. Lung pathological findings in HAP-exposed individuals demonstrate greater small airways fibrosis and less emphysema compared with cigarette smokers. Field studies using questionnaires, air pollution monitoring and/or biomarkers are needed to better establish human risks. Some, but not all, studies suggest that improving cookstove efficiency or venting emissions may be associated with reduced respiratory symptoms, lung function decline in women and severe pneumonia in children. Current studies focus on fuel switching, stove technology replacements or upgrades and air filter devices. Several governments have initiated major programmes to accelerate the upgrade from solid fuels to clean fuels, particularly liquid petroleum gas, which provides research opportunities for the respiratory health community.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar em Ambientes Fechados/efeitos adversos , Biomarcadores , Gases/toxicidade , Doenças Respiratórias/induzido quimicamente , Poluentes Atmosféricos/química , Animais , Culinária , Gases/química , Produtos Domésticos , Humanos , Exposição por Inalação/efeitos adversos , Macrófagos Alveolares/patologia , Doenças Respiratórias/fisiopatologia , Inquéritos e Questionários
7.
RNA ; 22(8): 1250-60, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27277658

RESUMO

Lysine-specific histone demethylase 1 (LSD1) is an essential epigenetic regulator in metazoans and requires the co-repressor element-1 silencing transcription factor (CoREST) to efficiently catalyze the removal of mono- and dimethyl functional groups from histone 3 at lysine positions 4 and 9 (H3K4/9). LSD1 interacts with over 60 regulatory proteins and also associates with lncRNAs (TERRA, HOTAIR), suggesting a regulatory role for RNA in LSD1 function. We report that a stacked, intramolecular G-quadruplex (GQ) forming TERRA RNA (GG[UUAGGG]8UUA) binds tightly to the functional LSD1-CoREST complex (Kd ≈ 96 nM), in contrast to a single GQ RNA unit ([UUAGGG]4U), a GQ DNA ([TTAGGG]4T), or an unstructured single-stranded RNA. Stabilization of a parallel-stranded GQ RNA structure by monovalent potassium ions (K(+)) is required for high affinity binding to the LSD1-CoREST complex. These data indicate that LSD1 can distinguish between RNA and DNA as well as structured versus unstructured nucleotide motifs. Further, cross-linking mass spectrometry identified the primary location of GQ RNA binding within the SWIRM/amine oxidase domain (AOD) of LSD1. An ssRNA binding region adjacent to this GQ binding site was also identified via X-ray crystallography. This RNA binding interface is consistent with kinetic assays, demonstrating that a GQ-forming RNA can serve as a noncompetitive inhibitor of LSD1-catalyzed demethylation. The identification of a GQ RNA binding site coupled with kinetic data suggests that structured RNAs can function as regulatory molecules in LSD1-mediated mechanisms.


Assuntos
Quadruplex G , Histona Desmetilases/metabolismo , Lisina/metabolismo , RNA/metabolismo
8.
Immunity ; 30(4): 566-75, 2009 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-19362023

RESUMO

Virus-induced interlukin-1beta (IL-1beta) and IL-18 production in macrophages are mediated via caspase-1 pathway. Multiple microbial components, including viral RNA, are thought to trigger assembly of the cryopyrin inflammasome resulting in caspase-1 activation. Here, we demonstrated that Nlrp3(-/-) and Casp1(-/-) mice were more susceptible than wild-type mice after infection with a pathogenic influenza A virus. This enhanced morbidity correlated with decreased neutrophil and monocyte recruitment and reduced cytokine and chemokine production. Despite the effect on innate immunity, cryopyrin-deficiency was not associated with any obvious defect in virus control or on the later emergence of the adaptive response. Early epithelial necrosis was, however, more severe in the infected mutants, with extensive collagen deposition leading to later respiratory compromise. These findings reveal a function of the cryopyrin inflammasome in healing responses. Thus, cryopyrin and caspase-1 are central to both innate immunity and to moderating lung pathology in influenza pneumonia.


Assuntos
Proteínas de Transporte/metabolismo , Caspase 1/metabolismo , Imunidade Inata , Vírus da Influenza A/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Proteínas de Transporte/genética , Caspase 1/genética , Células Cultivadas , Regulação da Expressão Gênica , Predisposição Genética para Doença , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR
9.
Biochemistry ; 56(1): 3-13, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-27935277

RESUMO

Over billions of years of evolution, nature has embraced proteins as the major workhorse molecules of the cell. However, nearly every aspect of metabolism is dependent upon how structured RNAs interact with proteins, ligands, and other nucleic acids. Key processes, including telomere maintenance, RNA processing, and protein synthesis, require large RNAs that assemble into elaborate three-dimensional shapes. These RNAs can (i) act as flexible scaffolds for protein subunits, (ii) participate directly in substrate recognition, and (iii) serve as catalytic components. Here, we juxtapose the near atomic level interactions of three ribonucleoprotein complexes: ribonuclease P (involved in 5' pre-tRNA processing), the spliceosome (responsible for pre-mRNA splicing), and telomerase (an RNA-directed DNA polymerase that extends the ends of chromosomes). The focus of this perspective is profiling the structural and dynamic roles of RNAs at the core of these enzymes, highlighting how large RNAs contribute to molecular recognition and catalysis.


Assuntos
RNA não Traduzido/genética , Ribonuclease P/genética , Spliceossomos/genética , Telomerase/genética , Animais , Sequência de Bases , Biocatálise , Evolução Molecular , Humanos , Modelos Moleculares , Conformação de Ácido Nucleico , RNA/química , RNA/genética , RNA/metabolismo , Precursores de RNA/química , Precursores de RNA/genética , Precursores de RNA/metabolismo , RNA Catalítico/química , RNA Catalítico/genética , RNA Catalítico/metabolismo , RNA não Traduzido/química , RNA não Traduzido/metabolismo , Ribonuclease P/química , Ribonuclease P/metabolismo , Spliceossomos/química , Spliceossomos/metabolismo , Telomerase/química , Telomerase/metabolismo , Telômero/química , Telômero/genética , Telômero/metabolismo
10.
Cytokine ; 95: 70-79, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28237876

RESUMO

Infection with Mycobacterium tuberculosis (M.tb) is associated with increased deaths worldwide. Alveolar macrophages (AMs) play a critical role in host defense against infection with this pathogen. In this work we tested the hypothesis that passive transfer of normal AMs, IFN-γ activated AMs, or macrophages transduced to over-express IFN-γ into the lungs of immunosuppressed SCID mice, where resident macrophages are present but not functional, would enhance alveolar immunity and increase clearance of pulmonary M.tb infection. Accordingly, SCID mice were infected with M.tb intratracheally (I.T.), following which they received either control macrophages or macrophages overexpressing IFN-γ (J774A.1). The extent of M.tb infection was assessed at 30days post-M.tb infection. SCID mice administered macrophages over-expressing IFN-γ showed a significant decrease in M.tb burden and increased survival compared to J774A.1 control macrophages or untreated mice. This was further associated with a significant increase in IFN-γ and TNF-α mRNA and protein expression, as well as NF-κB (p65) mRNA, in the lungs. The increase in IFN-γ and TNF-α lung levels was inversely proportional to the number of M.tb organisms recovered. These results provide evidence that administration of macrophages overexpressing IFN-γ inhibit M.tb growth in vivo and may enhance host defense against M.tb infection.


Assuntos
Transferência Adotiva , Interferon gama/genética , Macrófagos/transplante , Tuberculose Pulmonar/terapia , Animais , Resistência à Doença , Suscetibilidade a Doenças , Tolerância Imunológica , Interferon gama/metabolismo , Pulmão/metabolismo , Camundongos Endogâmicos BALB C , Camundongos SCID , Fagocitose , Tuberculose Pulmonar/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
11.
Am J Public Health ; 106(7): 1235-42, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27196662

RESUMO

OBJECTIVES: To review how disasters introduce unique challenges to conducting population-based research and community-based participatory research (CBPR). METHODS: From 2007-2009, we conducted the Head-off Environmental Asthma in Louisiana (HEAL) Study in the aftermath of Hurricane Katrina in a Gulf Coast community facing an unprecedented triple burden: Katrina's and other disasters' impact on the environment and health, historic health disparities, and persistent environmental health threats. RESULTS: The unique triple burden influenced every research component; still, most existing CBPR principles were applicable, even though full adherence was not always feasible and additional tailored principles govern postdisaster settings. CONCLUSIONS: Even in the most challenging postdisaster conditions, CBPR can be successfully designed, implemented, and disseminated while adhering to scientific rigor.


Assuntos
Pesquisa Participativa Baseada na Comunidade/organização & administração , Desastres , Projetos de Pesquisa , Fortalecimento Institucional/organização & administração , Comunicação , Tempestades Ciclônicas , Meio Ambiente , Feminino , Nível de Saúde , Humanos , Relações Interinstitucionais , Louisiana , Masculino , Fatores Socioeconômicos
12.
J Asthma ; 53(8): 825-34, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27049234

RESUMO

OBJECTIVE: To report implementation strategies and outcomes of an evidence-based asthma counseling intervention. The Head-off Environmental Asthma in Louisiana (HEAL) intervention integrated asthma counseling (AC) capacity and addressed challenges facing children with asthma in post-disaster New Orleans. METHODS: The HEAL intervention enrolled 182 children (4-12 years) with moderate-to-severe persistent asthma. Recruitment occurred from schools in the Greater New Orleans area for one year. Participants received home environmental assessments and tailored asthma counseling sessions during the study period based on the National Cooperative Inner City Asthma Study and the Inner City Asthma Study. Primary (i.e., asthma symptoms) and secondary outcomes (i.e., healthcare utilization) were captured. During the study, changes were made to meet the demands of a post-hurricane and resource-poor environment which included changes to staffing, training, AC tools, and AC sessions. RESULTS: After study changes were made, the AC visit rate increased by 92.3%. Significant improvements were observed across several adherence measures (e.g., running out of medications (p = 0.009), financial/insurance problems for appointments (p = 0.006), worried about medication side-effects (p = 0.01), felt medications did not work (p < 0.001)). Additionally, an increasing number of AC visits was modestly associated with a greater reduction in symptoms (test-for-trend p = 0.059). CONCLUSION: By adapting to the needs of the study population and setting, investigators successfully implemented a counseling intervention that improved participant behaviors and clinical outcomes. The strategies for implementing the AC intervention may serve as a guide for managing asthma and other chronic conditions in resource-poor settings.


Assuntos
Asma , Educação de Pacientes como Assunto , Asma/tratamento farmacológico , Asma/prevenção & controle , Criança , Pré-Escolar , Cidades , Aconselhamento , Prática Clínica Baseada em Evidências , Promoção da Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Louisiana , Adesão à Medicação , Áreas de Pobreza , População Urbana
13.
Am J Respir Crit Care Med ; 192(1): 11-6, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25945507

RESUMO

There is growing evidence that a number of pulmonary diseases affect women differently and with a greater degree of severity than men. The causes for such sex disparity is the focus of this Blue Conference Perspective review, which explores basic cellular and molecular mechanisms, life stages, and clinical outcomes based on environmental, sociocultural, occupational, and infectious scenarios, as well as medical health beliefs. Owing to the breadth of issues related to women and lung disease, we present examples of both basic and clinical concepts that may be the cause for pulmonary disease disparity in women. These examples include those diseases that predominantly affect women, as well as the rising incidence among women for diseases traditionally occurring in men, such as chronic obstructive pulmonary disease. Sociocultural implications of pulmonary disease attributable to biomass burning and infectious diseases among women in low- to middle-income countries are reviewed, as are disparities in respiratory health among sexual minority women in high-income countries. The implications of the use of complementary and alternative medicine by women to influence respiratory disease are examined, and future directions for research on women and respiratory health are provided.


Assuntos
Saúde Global , Disparidades nos Níveis de Saúde , Disparidades em Assistência à Saúde , Pneumopatias/etiologia , Saúde da Mulher , Terapias Complementares , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Pneumopatias/diagnóstico , Pneumopatias/terapia , Fatores de Risco , Fatores Sexuais , Sexualidade , Fatores Socioeconômicos
14.
J Pharmacol Exp Ther ; 351(1): 190-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25100753

RESUMO

The objective of the present studies was to characterize the pharmacologic properties of GSK-961081 [TD-5959; (R)-1-(3-((2-chloro-4-(((2-hydroxy-2-(8-hydroxy-2-oxo-1,2-dihydroquinolin-5-yl)ethyl)amino)methyl)-5-methoxyphenyl)amino)-3-oxopropyl) piperidin-4-yl [1,1'-biphenyl]-2-ylcarbamate], a novel first-in-class inhaled bifunctional compound possessing both muscarinic antagonist (MA) and ß2-adrenoceptor agonist (BA) properties (MABA). In competition radioligand binding studies at human recombinant receptors, GSK-961081 displayed high affinity for hM2 (Ki = 1.4 nM), hM3 muscarinic receptors (Ki = 1.3 nM) and hß2-adrenoceptors (Ki = 3.7 nM). GSK-961081 behaved as a potent hß2-adrenoceptor agonist (EC50 = 0.29 nM for stimulation of cAMP levels) with 440- and 320-fold functional selectivity over hß1- and hß3-adrenoceptors, respectively. In guinea pig isolated tracheal tissues, GSK-961081 produced smooth muscle relaxation through MA (EC50 = 50.2 nM), BA (EC50=24.6 nM), and MABA (EC50 = 11 nM) mechanisms. In the guinea pig bronchoprotection assay, inhaled GSK-961081 produced potent, dose-dependent inhibition of bronchoconstrictor responses via MA (ED50 = 33.9 µg/ml), BA (ED50 = 14.1 µg/ml), and MABA (ED50 = 6.4 µg/ml) mechanisms. Significant bronchoprotective effects of GSK-961081 were evident in guinea pigs via MA, BA, and MABA mechanisms for up to 7 days after dosing. The lung selectivity index of GSK-961081 in guinea pigs was 55- to 110-fold greater than that of tiotropium with respect to systemic antimuscarinic antisialagogue effects and was 10-fold greater than that of salmeterol with respect to systemic ß2-adrenoceptor hypotensive effects. These preclinical findings studies suggest that GSK-961081 has the potential to be a promising next-generation inhaled lung-selective bronchodilator for the treatment of airway diseases, including chronic obstructive pulmonary disease.


Assuntos
Antagonistas de Receptores Adrenérgicos beta 2/farmacologia , Broncodilatadores/farmacologia , Carbamatos/farmacologia , Antagonistas Muscarínicos/farmacologia , Quinolonas/farmacologia , Antagonistas de Receptores Adrenérgicos beta 2/efeitos adversos , Antagonistas de Receptores Adrenérgicos beta 2/farmacocinética , Albuterol/análogos & derivados , Albuterol/farmacocinética , Albuterol/farmacologia , Animais , Broncodilatadores/efeitos adversos , Broncodilatadores/farmacocinética , Células CHO , Carbamatos/efeitos adversos , Carbamatos/farmacocinética , Cricetinae , Cricetulus , AMP Cíclico/metabolismo , Avaliação Pré-Clínica de Medicamentos , Cobaias , Células HEK293 , Humanos , Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Antagonistas Muscarínicos/efeitos adversos , Antagonistas Muscarínicos/farmacocinética , Relaxamento Muscular , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Ligação Proteica , Quinolonas/efeitos adversos , Quinolonas/farmacocinética , Receptores Adrenérgicos beta/metabolismo , Receptores Muscarínicos/metabolismo , Xinafoato de Salmeterol , Derivados da Escopolamina/farmacocinética , Derivados da Escopolamina/farmacologia , Brometo de Tiotrópio , Distribuição Tecidual , Traqueia/efeitos dos fármacos , Traqueia/fisiologia
15.
J Clin Rheumatol ; 20(6): 301-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25160011

RESUMO

BACKGROUND: Controversy exists in understanding the effects of age at onset and comorbidities in predicting rheumatoid arthritis (RA) response to biologic therapy. OBJECTIVE: The objective of this study was to investigate the influence of age at onset and number of comorbidities on Health Assessment Questionnaire-Disability Index (HAQ-DI) and Clinical Disease Activity Index (CDAI) responses in active RA patients after 6 months of treatment with etanercept. METHODS: One thousand eight hundred ninety-nine RA patients were assessed after 6 months of etanercept therapy. Patients met the following inclusion criteria: initiated etanercept, continued therapy for at least 6 months, and were not in CDAI low disease activity (LDA) at baseline (CDAI ≤10.0). Changes in HAQ-DI and CDAI scores over 6 months were analyzed across age of onset quintiles. Multivariate regression models evaluated the independent association between both age at onset and number of comorbidities with change in HAQ-DI/CDAI scores or achieving LDA, while accounting for other covariates. RESULTS: Significant improvements in HAQ-DI and CDAI scores were observed in all age-onset groups, although HAQ-DI improvements were less in older-onset patients. Results of multiple linear regression demonstrated that younger age at onset, higher baseline HAQ-DI/CDAI score, rheumatoid factor positivity, shorter disease duration, and fewer comorbidities at baseline were independently associated with improvement in both HAQ-DI and CDAI scores. Similarly, achieving CDAI LDA after 6 or more months of etanercept was associated with younger age at onset, higher baseline CDAI, shorter disease duration, and fewer comorbidities. CONCLUSIONS: These patients with older-onset RA and more comorbidities clinically improved with etanercept, but had lower odds of achieving CDAI LDA. Age of onset and number of comorbidities may be important in determining RA tumor necrosis factor inhibitor response.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Avaliação da Deficiência , Imunoglobulina G/uso terapêutico , Receptores do Fator de Necrose Tumoral/uso terapêutico , Índice de Gravidade de Doença , Inquéritos e Questionários , Adulto , Fatores Etários , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Antirreumáticos/efeitos adversos , Artrite Reumatoide/epidemiologia , Estudos de Coortes , Comorbidade , Etanercepte , Feminino , Seguimentos , Humanos , Imunoglobulina G/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Análise de Regressão , Medição de Risco , Resultado do Tratamento , Estados Unidos
16.
Environ Toxicol Chem ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837715

RESUMO

Springtails (subclass: Collembola) represent one of the most extensively studied invertebrate groups in soil ecotoxicology. This is because of their ease of laboratory culture, significant ecological role, and sensitivity to environmental contaminants. Folsomia candida (family: Isotomidae) is a globally widespread parthenogenetic species that is prevalent in laboratory toxicity testing with springtails. Conversely, Arrhopalites caecus (family: Arrhopalitidae), a parthenogenic globular springtail species, remains untested in soil ecotoxicology. This species is found in diverse habitats, including cave systems and forest leaf litter, and has a global distribution. The sensitivity of A. caecus to environmental contaminants, such as neonicotinoid insecticides, as well as its life history and optimal culturing conditions, are largely unknown. The present study describes the establishment of a pure A. caecus laboratory culture and characterization of its life cycle and culturing conditions. We assessed the sensitivity of A. caecus to various insecticides, including exposures to the neonicotinoid thiamethoxam in soil and through a novel feeding assay as well as to clothianidin and cyantraniliprole in spiked soil exposures. In 7- and 14-day exposures to thiamethoxam in agricultural soil, the 50% lethal concentration (LC50) values were determined to be 0.129 mg/kg dry weight and 0.010 mg/kg dry weight, respectively. The 14-day LC50 for exposure to thiamethoxam via spiked food was determined to be 0.307 mg/kg dry weight. In addition, the 28-day 50% effect concentration for inhibition of juvenile production from cyantraniliprole exposure in the same soil type was 0.055 mg/kg dry weight. Challenges encountered in using this species included susceptibility to mite infestation and low adult survival rates in the 28-day cyantraniliprole test. Environ Toxicol Chem 2024;00:1-16. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

17.
Environ Toxicol Chem ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980316

RESUMO

The toxicity of neonicotinoids and many of their replacement insecticides to nontarget soil invertebrates such as earthworms has previously been established. However, the long-term effects of these substances on these organisms are largely unknown. In the field of soil ecotoxicology, lumbricid earthworms such as Eisenia andrei are used extensively due to the availability of standardized test methods and their adaptability to laboratory culture and testing. Multigenerational studies have gained popularity and attention in recent years, with a shift toward the use of long-term assays and lower concentrations of test chemicals. The use of exposure concentrations that include those measured in a monitoring program carried out by the Government of Ontario presents a realistic exposure scenario that may not show significant effects in contemporary, shorter term studies. We used current standardized test methods as a basis for the development of multigenerational studies on E. andrei. The effects of exposure to a single application of the insecticides thiamethoxam and cyantraniliprole on the survival and reproduction of E. andrei were observed over three (thiamethoxam) or two (cyantraniliprole) generations using consecutive reproduction tests. No significant impacts on adult survival were reported in any generation for either insecticide, whereas reproduction decreased between the first and second generations in the thiamethoxam test, with median effective concentration (EC50) values of 0.022 mg/kg dry weight reported for the first generation compared with 0.002 mg/kg dry weight in the second generation. For cyantraniliprole, an EC50 of 0.064 was determined for the first generation compared with 0.016 mg/kg dry weight in the second generation. A third generation was completed for the thiamethoxam test, and a significant decrease in reproduction was observed in all treatments and controls compared with previous generations. No significant difference between thiamethoxam treatments and the control treatment was reported for the third generation. Collectively, these data indicate that exposure of oligochaetes to these two insecticides at concentrations representative of field conditions may result in long-term stresses. Environ Toxicol Chem 2024;00:1-13. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

18.
J Inorg Biochem ; 252: 112474, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38176365

RESUMO

To study how proline residues affect the dynamics of Ω-loop D (residues 70 to 85) of cytochrome c, we prepared G83P and G83A variants of yeast iso-1-cytochrome c (iso-1-Cytc) in the presence and absence of a K73H mutation. Ω-loop D is important in controlling both the electron transfer function of Cytc and the peroxidase activity of Cytc used in apoptosis because it provides the Met80 heme ligand. The G83P and G83A mutations have no effect on the global stability of iso-1-Cytc in presence or absence of the K73H mutation. However, both mutations destabilize the His73-mediated alkaline conformer relative to the native state. pH jump stopped-flow experiments show that the dynamics of the His73-mediated alkaline transition are significantly enhanced by the G83P mutation. Gated electron transfer studies show that the enhanced dynamics result from an increased rate of return to the native state, whereas the rate of loss of Met80 ligation is unchanged by the G83P mutation. Thus, the G83P substitution does not stiffen the conformation of the native state. Because bis-His heme ligation occurs when Cytc binds to cardiolipin-containing membranes, we studied the effect of His73 ligation on the peroxidase activity of Cytc, which acts as an early signal in apoptosis by causing oxygenation of cardiolipin. We find that the His73 alkaline conformer suppresses the peroxidase activity of Cytc. Thus, the bis-His ligated state of Cytc formed upon binding to cardiolipin is a negative effector for the peroxidase activity of Cytc early in apoptosis.


Assuntos
Citocromos c , Histidina , Citocromos c/química , Histidina/química , Cardiolipinas , Saccharomyces cerevisiae/metabolismo , Heme/química , Peroxidases/genética , Peroxidases/metabolismo , Concentração de Íons de Hidrogênio , Conformação Proteica
19.
Am J Physiol Lung Cell Mol Physiol ; 304(9): L571-8, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23457186

RESUMO

Household air pollution (HAP) from indoor burning of biomass or coal is a leading global cause of morbidity and mortality, mostly due to its association with acute respiratory infection in children and chronic respiratory and cardiovascular diseases in adults. Interventions that have significantly reduced exposure to HAP improve health outcomes and may reduce mortality. However, we lack robust, specific, and field-ready biomarkers to identify populations at greatest risk and to monitor the effectiveness of interventions. New scientific approaches are urgently needed to develop biomarkers of human exposure that accurately reflect exposure or effect. In this Perspective, we describe the global need for such biomarkers, the aims of biomarker development, and the state of development of tests that have the potential for rapid transition from laboratory bench to field use.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Biomarcadores/análise , Doenças Respiratórias/etiologia , Doença Aguda , Anisóis/análise , Monóxido de Carbono/análise , Carboxihemoglobina/análise , Metilação de DNA , Países em Desenvolvimento , Incêndios , Saúde Global , Glucose/análogos & derivados , Glucose/análise , Humanos , Isoprostanos/análise , Malondialdeído/análise , Material Particulado/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/análise , Infecções Respiratórias/etiologia
20.
Bioorg Med Chem Lett ; 23(5): 1456-61, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23347683

RESUMO

A series of 3-(phenoxy-phenyl-methyl)-pyrrolidine analogues were discovered to be potent and balanced norepinephrine (NE) and serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibitors. Several of these compounds were identified to have suitable in vitro pharmacokinetic properties for an orally dosed and CNS-targeted drug. Compound 39b, in particular, was identified as a potent NET and SERT reuptake inhibitor (NSRI) with minimal off-target activity and demonstrated robust efficacy in the spinal nerve ligation model of pain behavior.


Assuntos
Inibidores da Captação de Neurotransmissores/farmacologia , Pirrolidinas/química , Pirrolidinas/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Animais , Cristalografia por Raios X , Modelos Animais de Doenças , Humanos , Proteínas do Tecido Nervoso/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Norepinefrina/antagonistas & inibidores , Norepinefrina/química , Norepinefrina/metabolismo , Dor/tratamento farmacológico , Pirrolidinas/síntese química , Ratos , Relação Estrutura-Atividade
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