RESUMO
The outbreak of COVID-19 caused by SARS-CoV-2 has resulted in more than 50 million confirmed cases and over 1 million deaths worldwide as of November 2020. Currently, there are no effective antivirals approved by the Food and Drug Administration to contain this pandemic except the antiviral agent remdesivir. In addition, the trimeric spike protein on the viral surface is highly glycosylated and almost 200,000 variants with mutations at more than 1,000 positions in its 1,273 amino acid sequence were reported, posing a major challenge in the development of antibodies and vaccines. It is therefore urgently needed to have alternative and timely treatments for the disease. In this study, we used a cell-based infection assay to screen more than 3,000 agents used in humans and animals, including 2,855 small molecules and 190 traditional herbal medicines, and identified 15 active small molecules in concentrations ranging from 0.1 nM to 50 µM. Two enzymatic assays, along with molecular modeling, were then developed to confirm those targeting the virus 3CL protease and the RNA-dependent RNA polymerase. Several water extracts of herbal medicines were active in the cell-based assay and could be further developed as plant-derived anti-SARS-CoV-2 agents. Some of the active compounds identified in the screen were further tested in vivo, and it was found that mefloquine, nelfinavir, and extracts of Ganoderma lucidum (RF3), Perilla frutescens, and Mentha haplocalyx were effective in a challenge study using hamsters as disease model.
Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , SARS-CoV-2/efeitos dos fármacos , Adulto , Animais , Antivirais/química , Antivirais/uso terapêutico , COVID-19/epidemiologia , COVID-19/virologia , Chlorocebus aethiops , Cricetinae , Modelos Animais de Doenças , Reposicionamento de Medicamentos/métodos , Feminino , Humanos , Masculino , Pandemias , Extratos Vegetais/farmacologia , SARS-CoV-2/genética , Células VeroRESUMO
Hemagglutinin (HA) is the immunodominant protein of the influenza virus. We previously showed that mice injected with a monoglycosylated influenza A HA (HAmg) produced cross-strain-reactive antibodies and were better protected than mice injected with a fully glycosylated HA (HAfg) during lethal dose challenge. We employed a single B-cell screening platform to isolate the cross-protective monoclonal antibody (mAb) 651 from mice immunized with the HAmg of A/Brisbane/59/2007 (H1N1) influenza virus (Bris/07). The mAb 651 recognized the head domain of a broad spectrum of HAs from groups 1 and 2 influenza A viruses and offered prophylactic and therapeutic efficacy against A/California/07/2009 (H1N1) (Cal/09) and Bris/07 infections in mice. The antibody did not possess neutralizing activity; however, antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis mediated by natural killer cells and alveolar macrophages were important in the protective efficacy of mAb 651. Together, this study highlighted the significance of effector functions for non-neutralizing antibodies to exhibit protection against influenza virus infection.
Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/farmacologia , Citotoxicidade Celular Dependente de Anticorpos , Vírus da Influenza A/imunologia , Células Matadoras Naturais/imunologia , Macrófagos Alveolares/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/farmacologia , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/virologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/virologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologiaRESUMO
BACKGROUND: Amyotrophic lateral sclerosis (ALS) associated with TAR DNA-binding protein 43 (TDP-43) aggregation has been considered as a lethal and progressive motor neuron disease. Recent studies have shown that both C-terminal TDP-43 (C-TDP-43) aggregates and oligomers were neurotoxic and pathologic agents in ALS and frontotemporal lobar degeneration (FTLD). However, misfolding protein has long been considered as an undruggable target by applying conventional inhibitors, agonists, or antagonists. To provide this unmet medical need, we aim to degrade these misfolding proteins by designing a series of proteolysis targeting chimeras (PROTACs) against C-TDP-43. METHODS: By applying filter trap assay, western blotting, and microscopy imaging, the degradation efficiency of C-TDP-43 aggregates was studied in Neuro-2a cells overexpressing eGFP-C-TDP-43 or mCherry-C-TDP-43. The cell viability was characterized by alarmarBlue assay. The beneficial and disaggregating effects of TDP-43 PROTAC were examined with the YFP-C-TDP-43 transgenic C. elegans by motility assay and confocal microscopy. The impact of TDP-43 PROTAC on C-TDP-43 oligomeric intermediates was monitored by fluorescence lifetime imaging microscopy and size exclusion chromatography in the Neuro-2a cells co-expressing eGFP-C-TDP-43 and mCherry-C-TDP-43. RESULTS: Four PROTACs with different linker lengths were synthesized and characterized. Among these chimeras, PROTAC 2 decreased C-TDP-43 aggregates and relieved C-TDP-43-induced cytotoxicity in Neuro-2a cells without affecting endogenous TDP-43. We showed that PROTAC 2 bound to C-TDP-43 aggregates and E3 ligase to initiate ubiquitination and proteolytic degradation. By applying advanced microscopy, it was further shown that PROTAC 2 decreased the compactness and population of C-TDP-43 oligomers. In addition to cellular model, PROTAC 2 also improved the motility of transgenic C. elegans by reducing the C-TDP-43 aggregates in the nervous system. CONCLUSIONS: Our study demonstrated the dual-targeting capacity of the newly-designed PROTAC 2 against both C-TDP-43 aggregates and oligomers to reduce their neurotoxicity, which shed light on the potential drug development for ALS as well as other neurodegenerative diseases.
Assuntos
Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Animais , Esclerose Lateral Amiotrófica/metabolismo , Doenças Neurodegenerativas/genética , Proteólise , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA/metabolismo , Animais Geneticamente ModificadosRESUMO
PURPOSE: We have previously shown that the TT genotype (rs579459 location of the ABO gene) is significantly associated with circulating levels of e-selectin in patients with suspected obstructive sleep apnea (OSA). We hypothesized that this genotype would be associated with incident cardiovascular disease (CVD). METHODS: Patients with suspected OSA who had a full diagnostic polysomnogram from 2003 to 2011 were recruited; CV events occurring within 8 years of polysomnography were identified by linkage to provincial health databases. Cox proportional hazards models were used to evaluate the incidence of first CV events as a function of the rs579459 genotype. RESULTS: In this targeted study, 408 patients were studied, and 39 incident events were identified. A larger proportion of patients with the TT genotype had an event (31/247; 12.6%) than the CT and CC genotypes (8/161; 5.0%); in univariate analysis, the TT genotype was significantly associated with CV events (HR = 2.53; 95% CI = 1.16-5.51, p = 0.02). After adjustment for age, AHI, sex, smoking, diabetes, statin use, and BMI, the TT genotype remained a significant predictor (HR = 2.35; 95% CI = 1.02-5.42, p = 0.046). No events were found in patients with an absence of both OSA and the TT genotype (N = 30). The effect of the SNP was partially (16.2%) mediated by e-selectin levels. CONCLUSION: This is the first study to examine genetic variants as a risk factor for incident CVD in the context of OSA. Although these results are preliminary and in need of replication, it suggests that genetic markers may become useful in helping to guide precision clinical care.
Assuntos
Doenças Cardiovasculares , Apneia Obstrutiva do Sono , Humanos , Selectina E/genética , Projetos Piloto , Fatores de Risco , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Polimorfismo Genético , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/genéticaRESUMO
Vaccination has been used to control the spread of seasonal flu; however, the virus continues to evolve and escape from host immune response through mutation and increasing glycosylation. Efforts have been directed toward development of a universal vaccine with broadly protective activity against multiple influenza strains and subtypes. Here we report the design and evaluation of various chimeric vaccines based on the most common avian influenza H5 and human influenza H1 sequences. Of these constructs, the chimeric HA (cHA) vaccine with consensus H5 as globular head and consensus H1 as stem was shown to elicit broadly protective CD4+ and CD8+ T cell responses. Interestingly, the monoglycosylated cHA (cHAmg) vaccine with GlcNAc on each glycosite induced more stem-specific antibodies, with higher antibody-dependent cellular cytotoxicity (ADCC), and better neutralizing and stronger cross-protection activities against H1, H3, H5, and H7 strains and subtypes. Moreover, the cHAmg vaccine combined with a glycolipid adjuvant designed for class switch further enhanced the vaccine efficacy with more IFN-γ, IL-4, and CD8+ memory T cells produced.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proteção Cruzada/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Orthomyxoviridae/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Citotoxicidade Celular Dependente de Anticorpos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Modelos Animais de Doenças , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Humanos , Influenza Humana/virologia , Camundongos , Modelos Moleculares , Testes de Neutralização , Orthomyxoviridae/classificação , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/imunologia , Relação Estrutura-Atividade , VacinaçãoRESUMO
A series of salicylanilide compounds was previously identified as antibacterial agents that inhibit the peptidoglycan formation. To find the exact binding mode, we synthesized a benzophenone-containing salicylanilide compound (1) and used it as a photoaffinity probe to label Acinetobacter baumannii penicillin-binding protein (PBP1b). After incubation and photo-irradiation, the labeled protein was subjected to trypsin digestion, dialysis enrichment, LC-ESI-MS/MS analysis, and Mascot search to reveal an octadecapeptide sequence 364RQLRTEYQESDLTNQGLR381 that was labeled at E372. Our molecular docking experiments suggest a hydrophobic pocket surrounded by R367 and E372 is the binding site of salicylanilide 1. The pocket lies in between the transglycosylase and transpeptidase domains, thus binding of salicylanilide 1 can block the propagation pathway to disrupt the growth of peptidoglycan chain.
Assuntos
Peptidoglicano Glicosiltransferase , Benzofenonas/farmacologia , Escherichia coli/metabolismo , Simulação de Acoplamento Molecular , Peptidoglicano , Peptidoglicano Glicosiltransferase/química , Peptidoglicano Glicosiltransferase/metabolismo , Marcadores de Fotoafinidade , Salicilanilidas , Espectrometria de Massas em TandemRESUMO
BACKGROUND: Myocardial injury after non-cardiac surgery (MINS) occurs in approximately 8-13% of patients and has significant 30-day mortality. Patients with obstructive sleep apnea (OSA) suffer recurrent hypoxemia during sleep and surgical patients with OSA are known to have increased risk of cardiorespiratory complications. We hypothesized that patients at high risk for OSA may have an increased risk of MINS. As a secondary analysis, we assessed rates of postoperative cardiopulmonary complications. METHODS: Adult patients undergoing elective knee or hip arthroplasty with STOPBANG score ≥ 5 were recruited. MINS was determined by measuring troponin-I on postoperative days 1 and 2. RESULTS: A total of 82 patients were studied. Only one patient had a positive troponin (MINS rate of 1.2%). The rate of cardiopulmonary complications was low (4.9%) and the 30-day mortality rate for these patients was 0. CONCLUSION: The incidence of MINS and postoperative cardiopulmonary complications in patients with elective arthroplasty and a high risk of OSA were low.
Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Isquemia Miocárdica/etiologia , Apneia Obstrutiva do Sono/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Troponina I/sangueRESUMO
Human endo-O-sulfatases (Sulf-1 and Sulf-2) are extracellular heparan sulfate proteoglycan (HSPG)-specific 6-O-endosulfatases, which regulate a multitude of cell-signaling events through heparan sulfate (HS)-protein interactions and are associated with the onset of osteoarthritis. These endo-O-sulfatases are transported onto the cell surface to liberate the 6-sulfate groups from the internal d-glucosamine residues in the highly sulfated subdomains of HSPGs. In this study, a variety of HS oligosaccharides with different chain lengths and N- and O-sulfation patterns via chemical synthesis were systematically studied about the substrate specificity of human Sulf-1 employing the fluorogenic substrate 4-methylumbelliferyl sulfate (4-MUS) in a competition assay. The trisaccharide sulfate IdoA2S-GlcNS6S-IdoA2S was found to be the minimal-size substrate for Sulf-1, and substitution of the sulfate group at the 6-O position of the d-glucosamine unit with the sulfonamide motif effectively inhibited the Sulf-1 activity with IC50 = 0.53 µM, Ki = 0.36 µM, and KD = 12 nM.
Assuntos
Inibidores Enzimáticos/química , Sulfatases/antagonistas & inibidores , Sulfonamidas/química , Sulfotransferases/antagonistas & inibidores , Trissacarídeos/química , Ensaios Enzimáticos , Inibidores Enzimáticos/síntese química , Heparitina Sulfato/química , Humanos , Cinética , Especificidade por Substrato , Sulfatases/química , Sulfonamidas/síntese química , Sulfotransferases/química , Trissacarídeos/síntese químicaRESUMO
PURPOSE: To investigate the relationship between obstructive sleep apnea (OSA) severity, body mass index (BMI), and circulating levels of inflammatory adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin). METHODS: A cross-sectional clinical cohort study on all consecutive adults referred to the University of British Columbia (UBC) Sleep Laboratory for a polysomnogram (PSG) for suspected OSA provided a morning blood sample. Samples were analyzed with multiplex immune assay (MilliporeSigma, CA) to assess the levels of adhesion molecules. RESULTS: 488 patients were studied; the majority were male (68%) with a mean age of 50 yrs, mean AHI of 23 events/hour, and mean BMI of 32 kg/m2. In multivariable linear regression models, all three adhesion molecules were significantly associated with BMI (E-selectin p < 0.0001; ICAM-1 p = 0.0007; VCAM-1 p = 0.0003). However, only E-selectin was independently associated with AHI (p = 0.02); there was no significant interaction between AHI and BMI for E-selectin (p = 0.33). CONCLUSIONS: Although all three adhesion molecules were associated with BMI, only E-selectin was independently associated with OSA severity. Future studies are needed to determine the clinical significance of the relationship between E-selectin and OSA.
Assuntos
Selectina E/sangue , Molécula 1 de Adesão Intercelular/sangue , Obesidade/complicações , Apneia Obstrutiva do Sono/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Adulto , Índice de Massa Corporal , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Polissonografia , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/complicaçõesRESUMO
Small studies have suggested that patients with chronic obstructive pulmonary disease (COPD) have poor sleep quality. Our aim was to examine the prevalence of subjective sleep-related complaints and predictors of poor sleep quality in a large community-based COPD cohort. We analyzed cross-sectional data on sleep questionnaire responses from the Canadian Cohort of Obstructive Lung Disease (CanCOLD) study, a population-based, prospective longitudinal cohort study across Canada. The cohort comprises a COPD group and two matched non-COPD (never-smokers and ever-smokers) groups. Sleep-related symptoms were assessed using questionnaires including Pittsburgh Sleep Quality Index (PSQI). A total score of PSQI > 5 is indicative of poor sleep quality. Health-related quality of life measures and the presence of mood disturbance were assessed using Short Form-36™ Health Survey (SF-36) multi-item questionnaires and Hospital Anxiety and Depression Scale (HADS), respectively. Predictors of poor sleep quality were analyzed using multivariable logistic regression analysis. Of the 1123 subjects, 263 were healthy controls, 323 at-risk controls, and 537 had COPD (297 had mild, 240 with moderate to severe disease). The mean PSQI score was not significantly different between groups. COPD patients with poor sleep quality had lower diffusion capacity, higher HADS anxiety and depression scores and lower SF-36 mental and physical component summary scores than COPD patients classified as good sleepers. The presence of restless legs and obstructive sleep apnea symptoms, waist circumference, predicted diffusion capacity and HADS anxiety and depression scores were identified as independent predictors of poor sleep quality.
Assuntos
Ansiedade/epidemiologia , Depressão/epidemiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Síndrome das Pernas Inquietas/epidemiologia , Apneia Obstrutiva do Sono/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Idoso , Ansiedade/psicologia , Canadá/epidemiologia , Estudos de Coortes , Depressão/psicologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Capacidade de Difusão Pulmonar , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/psicologia , Fatores de Risco , Índice de Gravidade de Doença , Sono , Transtornos do Sono-Vigília/fisiopatologia , Transtornos do Sono-Vigília/psicologia , Inquéritos e Questionários , Circunferência da CinturaRESUMO
Bacterial transpeptidase and transglycosylase on the surface are essential for cell wall synthesis, and many antibiotics have been developed to target the transpeptidase; however, the problem of antibiotic resistance has arisen and caused a major threat in bacterial infection. The transglycosylase has been considered to be another excellent target, but no antibiotics have been developed to target this enzyme. Here, we determined the crystal structure of the Staphylococcus aureus membrane-bound transglycosylase, monofunctional glycosyltransferase, in complex with a lipid II analog to 2.3 Å resolution. Our results showed that the lipid II-contacting residues are not only conserved in WT and drug-resistant bacteria but also significant in enzymatic activity. Mechanistically, we proposed that K140 and R148 in the donor site, instead of the previously proposed E156, are used to stabilize the pyrophosphate-leaving group of lipid II, and E100 in the acceptor site acts as general base for the 4-OH of GlcNAc to facilitate the transglycosylation reaction. This mechanism, further supported by mutagenesis study and the structure of monofunctional glycosyltransferase in complex with moenomycin in the donor site, provides a direction for antibacterial drugs design.
Assuntos
Glicosiltransferases/química , Lipídeos/química , Peptidoglicano/biossíntese , Staphylococcus aureus/enzimologia , Sequência de Aminoácidos , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Homologia de Sequência de AminoácidosRESUMO
We herein describe the first synthesis of iminosugar C-glycosides of α-D-GlcNAc-1-phosphate in 10 steps starting from unprotected D-GlcNAc. A diastereoselective intramolecular iodoamination-cyclization as the key step was employed to construct the central piperidine ring of the iminosugar and the C-glycosidic structure of α-D-GlcNAc. Finally, the iminosugar phosphonate and its elongated phosphate analogue were accessed. These phosphorus-containing iminosugars were coupled efficiently with lipophilic monophosphates to give lipid-linked pyrophosphate derivatives, which are lipid II mimetics endowed with potent inhibitory properties toward bacterial transglycosylases (TGase).
Assuntos
Acetilglucosamina/análogos & derivados , Proteínas de Bactérias/antagonistas & inibidores , Glicosídeos/química , Glicosiltransferases/antagonistas & inibidores , Glicosiltransferases/química , Imino Açúcares/síntese química , Acetilglucosamina/química , Proteínas de Bactérias/química , Glicosídeo Hidrolases/química , Imino Açúcares/química , Estrutura Molecular , EstereoisomerismoRESUMO
This study demonstrates that compounds 1-4 from an extract of Plectranthus amboinicus inhibit the binding of AP-1 to its consensus DNA sequence. Thymoquinone (5) was further identified as a nonpolar ingredient from the hexane extract of P. amboinicus to suppress the expression of lipopolysaccharide-induced tumor necrosis factor-alpha (TNF-α). We then synthesized 2-alkylidenyl-4-cyclopentene-1,3-diones as the designed biomimetics of thymoquinone, and found that compounds 8a, 8b and 8d were more potent TNF-α inhibitors.
Assuntos
Anti-Inflamatórios/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Óleos de Plantas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Humanos , Extratos Vegetais/química , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificaçãoRESUMO
The rapid genetic drift of influenza virus hemagglutinin is an obstacle to vaccine efficacy. Previously, we found that the consensus hemagglutinin DNA vaccine (pCHA5) can only elicit moderate neutralization activities toward the H5N1 clade 2.1 and clade 2.3 viruses. Two approaches were thus taken to improve the protection broadness of CHA5. The first one was to include certain surface amino acids that are characteristic of clade 2.3 viruses to improve the protection profiles. When we immunized mice with CHA5 harboring individual mutations, the antibodies elicited by CHA5 containing P157S elicited higher neutralizing activity against the clade 2.3 viruses. Likewise, the viruses pseudotyped with hemagglutinin containing 157S became more susceptible to neutralization. The second approach was to update the consensus sequence with more recent H5N1 strains, generating a second-generation DNA vaccine pCHA5II. We showed that pCHA5II was able to elicit higher cross-neutralization activities against all H5N1 viruses. Comparison of the neutralization profiles of CHA5 and CHA5II, and the animal challenge studies, revealed that CHA5II induced the broadest protection profile. We concluded that CHA5II combined with electroporation delivery is a promising strategy to induce antibodies with broad cross-reactivities against divergent H5N1 influenza viruses.
Assuntos
Antígenos Virais/imunologia , Metabolismo dos Carboidratos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vacinas contra Influenza/imunologia , Mutação/genética , Testes de Neutralização , Vacinas de DNA/imunologia , Sequência de Aminoácidos , Aminoácidos/genética , Animais , Linhagem Celular , Proteção Cruzada/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Humanos , Soros Imunes/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Análise em Microsséries , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Polissacarídeos/metabolismo , Estrutura Terciária de Proteína , Receptores Virais/metabolismo , Vacinas de DNA/genéticaRESUMO
STUDY OBJECTIVES: To determine if obstructive sleep apnea (OSA) severity and/or biomarkers of inflammation/angiogenesis are associated with incident cancer in this clinical cohort. METHODS: Consenting adult patients at the University of British Columbia Hospital between 2003-2014 completed a questionnaire about their medical history and sleep habits prior to undergoing a polysomnogram (PSG). Blood samples were collected the morning after PSG and processed for biomarkers of inflammation and angiogenesis. The clinical, PSG, and biomarker data were linked to the British Columbia Cancer Registry to ascertain incident cancer diagnoses. Cox proportional hazard regression were used to assess the association between OSA severity and biomarker concentrations with cancer risk. RESULTS: A total of 1,990 patients were included in the analysis with a mean follow-up time of 12.8 years; 181 of them (9.1%) developed cancer after PSG. OSA severity was significantly associated with cancer risk after controlling for relevant covariates (hazard ratio (HR) = 1.08 per 10 events/h apnea-hypopnea index (AHI) increase, CI = 1.02-1.15, p=0.015). In an exploratory analysis, two biomarkers were significantly associated with an increased cancer risk after controlling for relevant covariates (HR per interquartile range (IQR) pg/mL increase of endostatin = 1.45, CI = 1.12-1.87, p=0.01 and HR for IQR pg/mL increase of VCAM-1 = 1.48, CI = 1.04-2.11, p=0.03, respectively). CONCLUSIONS: OSA severity was an independent risk factor for cancer. Furthermore, two circulating markers were significantly associated with cancer risk. If these preliminary findings can be reproduced in other cohorts, biomarkers could potentially be used to prognosticate OSA patients with respect to cancer risk.
RESUMO
Rationale: Obstructive sleep apnea (OSA) severity is typically assessed by the apnea-hypopnea index (AHI), a frequency-based metric that allocates equal weight to all respiratory events. However, more severe events may have a greater physiologic impact. Objectives: The purpose of this study was to determine whether the degree of event-related hypoxemia would be associated with the postevent physiologic response. Methods: Patients with OSA (AHI, ⩾5/h) from the multicenter Canadian Sleep and Circadian Network cohort were studied. Using mixed-effect linear regression, we examined associations between event-related hypoxic burden (HBev) assessed by the area under the event-related oxygen saturation recording with heart rate changes (ΔHRev), vasoconstriction (vasoconstriction burden [VCBev] assessed with photoplethysmography), and electroencephalographic responses (power ratio before and after events). Results: Polysomnographic recordings from 658 patients (median [interquartile range] age, 55.00 [45.00, 64.00] yr; AHI, 27.15 [14.90, 64.05] events/h; 42% female) were included in the analyses. HBev was associated with an increase in all physiologic responses after controlling for age, sex, body mass index, sleep stage, total sleep time, and study centers; for example, 1 standard deviation increase in HBev was associated with 0.21 [95% confidence interval, 0.2, 0.22], 0.08 [0.08, 0.09], and 0.22 [0.21, 0.23] standard deviation increases in ΔHRev, VCBev, and ß-power ratio, respectively. Conclusions: Increased event-related hypoxic burden was associated with greater responses across a broad range of physiologic signals. Future metrics that incorporate information about the variability of these physiologic responses may have promise in providing a more nuanced assessment of OSA severity.
Assuntos
Frequência Cardíaca , Hipóxia , Polissonografia , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono , Humanos , Masculino , Feminino , Apneia Obstrutiva do Sono/fisiopatologia , Hipóxia/fisiopatologia , Pessoa de Meia-Idade , Canadá , Frequência Cardíaca/fisiologia , Saturação de Oxigênio/fisiologia , Eletroencefalografia , Adulto , Modelos Lineares , Fotopletismografia , Vasoconstrição/fisiologia , IdosoRESUMO
Dual-targeting anticancer agents 4-29 are designed by combining the structural features of purine-type microtubule-disrupting compounds and HDAC inhibitors. A library of the conjugate compounds connected by appropriate linkers was synthesized and found to possess HDACs inhibitory activity and render microtubule fragmentation by activating katanin, a microtubule-severing protein. Among various zinc-binding groups, hydroxamic acid shows the highest inhibitory activity of Class I HDACs, which was also reconfirmed by three-dimensional quantitative structure-activity relationship (3D-QSAR) pharmacophore prediction. The purine-hydroxamate conjugates exhibit enhanced cytotoxicity against MDA-MB231 breast cancer cells, H1975 lung cancer cells, and various clinical isolated non-small-cell lung cancer cells with different epidermal growth factor receptor (EGFR) status. Pyridyl substituents could be used to replace the C2 and N9 phenyl moieties in the purine-type scaffold, which can help to improve the solubility under physiological conditions, thus increasing cytotoxicity. In mice treated with the purine-hydroxamate conjugates, the tumor growth rate was significantly reduced without causing toxic effects. Our study demonstrates the potential of the dual-targeting purine-hydroxamate compounds for cancer monotherapy.
Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Linhagem Celular Tumoral , Histona Desacetilases/metabolismo , Antineoplásicos/química , Inibidores de Histona Desacetilases/química , Microtúbulos/metabolismo , Purinas/farmacologia , Ácidos Hidroxâmicos/química , Relação Estrutura-Atividade , Proliferação de CélulasRESUMO
The synthesis of ß-(1â4)-linked hexa- to octamannoses and their partially acetylated derivatives was efficiently carried out by assembly of appropriate oligomeric fragments using ß-selective glucosylation followed by gluco to manno epimerization at a late stage of the synthetic pathway. In the course of this study, we also observed that 2-O-acetylated oligomannoses coexisted in equilibrium with the 3-O-acetylated isomers due to intramolecular migration of the acetyl group. Bioactivity of the synthetic oligomannoses and partially acetylated derivatives was investigated in order to identify the possible smallest oligomer for induction of cytokines as that shown in the polysaccharides extracted from Dendrobium huoshanense.
Assuntos
Dendrobium/química , Fator Estimulador de Colônias de Granulócitos/biossíntese , Oligossacarídeos/farmacologia , Acetilação , Animais , Configuração de Carboidratos , Linhagem Celular , Relação Dose-Resposta a Droga , Camundongos , Dados de Sequência Molecular , Oligossacarídeos/síntese química , Oligossacarídeos/química , Relação Estrutura-AtividadeRESUMO
Acute short-term noninvasive ventilation (NIV) for hypercapnic respiratory failure in chronic obstructive pulmonary disease (COPD) has well-established benefits; however, the role of long-term home NIV remains controversial. In the past decade, studies utilizing aggressive NIV settings to maximally reduce carbon dioxide levels (PaCO2) have resulted in several positive clinical trials and led to updated guidelines on home NIV for stable hypercapnic COPD patients. This clinical respiratory review discusses the high-intensity NIV approach, summarizes recent key trials and guidelines pertaining to home NIV in COPD, and considers key clinical questions for future research and application in the Canadian context. With recent evidence and Canadian Thoracic Society (CTS) guidelines supporting the use of NIV in carefully selected COPD patients with persistent daytime hypercapnia, we believe it is time to reconsider our approach.