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1.
Artigo em Inglês | MEDLINE | ID: mdl-38782726

RESUMO

BACKGROUND AND HYPOTHESIS: Volenrelaxin, is a half-life-extended recombinant human relaxin protein developed for improving kidney perfusion and cardiorenal function. This study assessed the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of volenrelaxin following single- and multiple-ascending doses (SAD and MAD) administration. METHODS: In this Phase 1, 4-part, randomized, double-blinded, placebo-controlled SAD and MAD study in healthy participants, SAD participants (n = 56) received an intravenous (IV) or subcutaneous (SC) dose of volenrelaxin or placebo in a dose-ascending manner. MAD participants (n = 77) received volenrelaxin or placebo SC once weekly for 5 weeks. Effective renal plasma flow (ERPF) and measured glomerular filtration rate (mGFR) were determined by para-aminohippurate and iohexol clearance, respectively. RESULTS: Volenrelaxin demonstrated an extended half-life and increased acute and chronic placebo-adjusted ERPF change from baseline by 50% and 44%, respectively (p < 0.0001). Measured GFR was unchanged, while filtration fraction and afferent/efferent renal arteriolar resistances were reduced. Systolic and diastolic blood pressures decreased, and pulse rate increased with increasing volenrelaxin exposures, demonstrating maximal model-derived placebo-adjusted changes (90% confidence interval) of -6.16 (-8.04, -4.28) mmHg, -6.10 (-7.61, -4.58) mmHg, and + 4.39 (3.38, 5.39) bpm, respectively. Adverse events were mild, with no difference in orthostatic hypotension between volenrelaxin and placebo. CONCLUSION: Volenrelaxin was well-tolerated, safe and suitable for weekly SC dosing. Volenrelaxin showed a sustained improvement in kidney perfusion upon repeated dosing, supporting further clinical development in chronic kidney disease and chronic heart failure. Clinical trial registration: NCT04768855.

2.
Pharmacogenomics J ; 23(6): 169-177, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37689822

RESUMO

Adverse drug events (ADEs) account for a significant mortality, morbidity, and cost burden. Pharmacogenetic testing has the potential to reduce ADEs and inefficacy. The objective of this INGENIOUS trial (NCT02297126) analysis was to determine whether conducting and reporting pharmacogenetic panel testing impacts ADE frequency. The trial was a pragmatic, randomized controlled clinical trial, adapted as a propensity matched analysis in individuals (N = 2612) receiving a new prescription for one or more of 26 pharmacogenetic-actionable drugs across a community safety-net and academic health system. The intervention was a pharmacogenetic testing panel for 26 drugs with dosage and selection recommendations returned to the health record. The primary outcome was occurrence of ADEs within 1 year, according to modified Common Terminology Criteria for Adverse Events (CTCAE). In the propensity-matched analysis, 16.1% of individuals experienced any ADE within 1-year. Serious ADEs (CTCAE level ≥ 3) occurred in 3.2% of individuals. When combining all 26 drugs, no significant difference was observed between the pharmacogenetic testing and control arms for any ADE (Odds ratio 0.96, 95% CI: 0.78-1.18), serious ADEs (OR: 0.91, 95% CI: 0.58-1.40), or mortality (OR: 0.60, 95% CI: 0.28-1.21). However, sub-group analyses revealed a reduction in serious ADEs and death in individuals who underwent pharmacogenotyping for aripiprazole and serotonin or serotonin-norepinephrine reuptake inhibitors (OR 0.34, 95% CI: 0.12-0.85). In conclusion, no change in overall ADEs was observed after pharmacogenetic testing. However, limitations incurred during INGENIOUS likely affected the results. Future studies may consider preemptive, rather than reactive, pharmacogenetic panel testing.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Testes Farmacogenômicos , Humanos , Aripiprazol , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/genética , Norepinefrina , Serotonina
3.
J Pharmacol Exp Ther ; 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35798386

RESUMO

We investigated the acute and chronic effects of efavirenz, a widely used antiretroviral drug, and CYP2B6 genotypes on the disposition of racemic and stereoisomers of bupropion (BUP) and its active metabolites, 4-hydroxyBUP, threohydroBUP and erythrohydroBUP. The primary objective of this study was to test how multiple processes unique to the efavirenz-CYP2B6 genotype interaction influence the extent of efavirenz-mediated drug-drug interaction (DDI) with the CYP2B6 probe substrate BUP. In a three-phase, sequential, open-label study, healthy volunteers (N=53) were administered a single 100 mg oral dose of BUP alone (control phase), with a single 600 mg oral efavirenz dose (inhibition phase), and after 17-days pretreatment with efavirenz (600 mg/day) (induction phase). Compared to the control phase, we show for the first time that efavirenz significantly decreases and chronically increases the exposure of hydroxyBUP and its diastereomers, respectively, and these interactions were CYP2B6 genotype dependent. Chronic efavirenz enhances the elimination of racemic BUP and its enantiomers as well as of threo- and erythro-hydroBUP and their diastereomers, suggesting additional novel mechanisms underlying efavirenz interaction with BUP. The effects of efavirenz and genotypes were nonstereospecific. In conclusion, acute and chronic administration of efavirenz inhibits and induces CYP2B6 activity. Efavirenz-BUP interaction is complex involving time- and CYP2B6 genotype-dependent inhibition and induction of primary and secondary metabolic pathways. Our findings highlight important implications to the safety and efficacy of BUP, study design considerations for future efavirenz interactions, and individualized drug therapy based on CYP2B6 genotypes. Significance Statement The effects of acute and chronic doses of efavirenz on the disposition of racemic and stereoisomers of BUP and its active metabolites were investigated in healthy volunteers. Efavirenz causes an acute inhibition, but chronic induction of CYP2B6 in a genotype dependent manner. Chronic efavirenz induces BUP reduction and the elimination of BUP active metabolites. Efavirenz's effects were non-stereospecific. These data reveal novel mechanisms underlying efavirenz DDI with BUP and provide important insights into time- and CYP2B6 genotype dependent DDIs.

4.
Pharm Res ; 38(10): 1677-1695, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34671921

RESUMO

PURPOSE: We developed an accessible method for labeling small extracellular vesicles (sEVs) without disrupting endogenous ligands. Using labeled sEVs administered to conscious rats, we developed a multiple compartment pharmacokinetic model to identify potential differences in the disposition of sEVs from three different cell types. METHODS: Crude sEVs were labeled with a non-homologous oligonucleotide and isolated from cell culture media using a commercial reagent. Jugular vein catheters were used to introduce EVs to conscious rats (n = 30) and to collect blood samples. Digital PCR was leveraged to allow for quantification over a wide dynamic range. Non-linear mixed effects analysis with first order conditional estimation - extended least squares (FOCE ELS) was used to estimate population-level parameters with associated intra-animal variability. RESULTS: 86.5% ± 1.5% (mean ± S.E.) of EV particles were in the 45-195 nm size range and demonstrated protein and lipid markers of endosomal origin. Incorporated oligonucleotide was stable in blood and detectable over five half-lives. Data were best described by a three-compartment model with one elimination from the central compartment. We performed an observation-based simulated posterior predictive evaluation with prediction-corrected visual predictive check. Covariate and bootstrap analyses identified cell type having an influence on peripheral volumes (V2 and V3) and clearance (Cl3). CONCLUSIONS: Our method relies upon established laboratory techniques, can be tailored to a variety of biological questions regarding the pharmacokinetic disposition of extracellular vesicles, and will provide a complementary approach for the of study EV ligand-receptor interactions in the context of EV uptake and targeted therapeutics.


Assuntos
Vesículas Extracelulares/metabolismo , Nanopartículas/metabolismo , Oligonucleotídeos/farmacocinética , Animais , Sequência de Bases , Transporte Biológico , Caenorhabditis elegans/genética , Humanos , Ligantes , Lipídeos/química , Masculino , MicroRNAs , Modelos Biológicos , Oligonucleotídeos/metabolismo , Ratos Sprague-Dawley , Imagem Individual de Molécula
5.
J Am Chem Soc ; 140(1): 441-450, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29281274

RESUMO

We modify the fundamental electronic properties of metallic (1T phase) nanosheets of molybdenum disulfide (MoS2) through covalent chemical functionalization, and thereby directly influence the kinetics of the hydrogen evolution reaction (HER), surface energetics, and stability. Chemically exfoliated, metallic MoS2 nanosheets are functionalized with organic phenyl rings containing electron donating or withdrawing groups. We find that MoS2 functionalized with the most electron donating functional group (p-(CH3CH2)2NPh-MoS2) is the most efficient catalyst for HER in this series, with initial activity that is slightly worse compared to the pristine metallic phase of MoS2. The p-(CH3CH2)2NPh-MoS2 is more stable than unfunctionalized metallic MoS2 and outperforms unfunctionalized metallic MoS2 for continuous H2 evolution within 10 min under the same conditions. With regards to the entire studied series, the overpotential and Tafel slope for catalytic HER are both directly correlated with the electron donating strength of the functional group. The results are consistent with a mechanism involving ground-state electron donation or withdrawal to/from the MoS2 nanosheets, which modifies the electron transfer kinetics and catalytic activity of the MoS2 nanosheet. The functional groups preserve the metallic nature of the MoS2 nanosheets, inhibiting conversion to the thermodynamically stable semiconducting state (2H) when mildly annealed in a nitrogen atmosphere. We propose that the electron density and, therefore, reactivity of the MoS2 nanosheets are controlled by the attached functional groups. Functionalizing nanosheets of MoS2 and other transition metal dichalcogenides provides a synthetic chemical route for controlling the electronic properties and stability within the traditionally thermally unstable metallic state.

6.
Inhal Toxicol ; 30(13-14): 553-567, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30849254

RESUMO

We compared early biological changes in mice after inhalation exposures to cigarette smoke or e-vapor aerosols (MarkTen® cartridge with Carrier, Test-1, or Test-2 formulations; 4% nicotine). Female C57BL/6 mice were exposed to 3R4F cigarette smoke or e-vapor aerosols by nose-only inhalation for up to 4 hours/day, 5 days/week, for 3 weeks. The 3R4F and e-vapor exposures were set to match the target nose port aerosol nicotine concentration (∼41 µg/L). Only the 3R4F group showed postexposure clinical signs such as tremors and lethargy. At necropsy, the 3R4F group had significant increases in lung weight and changes in bronchoalveolar lavage parameters, as well as microscopic findings in the respiratory tract. The e-vapor groups had minimal microscopic changes, including squamous metaplasia in laryngeal epiglottis, and histiocytic infiltrates in the lung (Test-2 group only). The 3R4F group had a higher incidence and severity of microscopic findings compared to any e-vapor group. Transcriptomic analysis also showed that the 3R4F group had the highest number of differentially expressed genes compared to Sham Control. Among e-vapor groups, Test-2 group had more differentially expressed genes but the magnitude of gene expression-based network perturbations in all e-vapor groups was ∼94% less than the 3R4F group. On proteome analysis in the lung, differentially regulated proteins were detected in the 3R4F group only. In conclusion, 3-weeks of 3R4F exposure induced molecular and microscopic changes associated with smoking-related diseases in the respiratory tract, while e-vapor exposures showed substantially reduced biological activities.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Sistema Respiratório/efeitos dos fármacos , Fumaça/efeitos adversos , Produtos do Tabaco/efeitos adversos , Administração por Inalação , Aerossóis , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Carboxihemoglobina/análise , Feminino , Perfilação da Expressão Gênica , Camundongos Endogâmicos C57BL , Testes de Função Respiratória , Fenômenos Fisiológicos Respiratórios/efeitos dos fármacos , Sistema Respiratório/metabolismo , Sistema Respiratório/patologia
7.
Int J Mol Sci ; 18(3)2017 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-28335481

RESUMO

Colistin sulfate (polymixin E) is an antibiotic prescribed with increasing frequency for severe Gram-negative bacterial infections. As nephrotoxicity is a common side effect, the discovery of pharmacogenomic markers associated with toxicity would benefit the utility of this drug. Our objective was to identify genetic markers of colistin cytotoxicity that were also associated with expression of key proteins using an unbiased, whole genome approach and further evaluate the functional significance in renal cell lines. To this end, we employed International HapMap lymphoblastoid cell lines (LCLs) of Yoruban ancestry with known genetic information to perform a genome-wide association study (GWAS) with cellular sensitivity to colistin. Further association studies revealed that single nucleotide polymorphisms (SNPs) associated with gene expression and protein expression were significantly enriched in SNPs associated with cytotoxicity (p ≤ 0.001 for gene and p = 0.015 for protein expression). The most highly associated SNP, chr18:3417240 (p = 6.49 × 10-8), was nominally a cis-expression quantitative trait locus (eQTL) of the gene TGIF1 (transforming growth factor ß (TGFß)-induced factor-1; p = 0.021) and was associated with expression of the protein HOXD10 (homeobox protein D10; p = 7.17 × 10-5). To demonstrate functional relevance in a murine colistin nephrotoxicity model, HOXD10 immunohistochemistry revealed upregulated protein expression independent of mRNA expression in response to colistin administration. Knockdown of TGIF1 resulted in decreased protein expression of HOXD10 and increased resistance to colistin cytotoxicity. Furthermore, knockdown of HOXD10 in renal cells also resulted in increased resistance to colistin cytotoxicity, supporting the physiological relevance of the initial genomic associations.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Proteínas de Homeodomínio/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Antibacterianos/efeitos adversos , Antibacterianos/toxicidade , Linhagem Celular , Linhagem Celular Tumoral , Colistina/efeitos adversos , Colistina/toxicidade , Resistência a Medicamentos/genética , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
8.
J Shoulder Elbow Surg ; 25(9): 1542-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27068384

RESUMO

BACKGROUND: A distal tibia osteochondral allograft is a potential graft option for glenoid reconstruction because the distal tibia may have a similar radius of curvature (ROC) as the glenoid. This study evaluated ROC mismatch as measured on computed tomography (CT) scans between the glenoid, distal tibia, and humeral head. METHODS: Bilateral CT images were formatted for 10 decedents from the Office of the Medical Investigator database, giving 20 specimens per anatomic location. The ROCs of the glenoid, distal tibia, and humeral head were measured. A statistical model was generated to assess ROC mismatch of randomly paired distal tibias and glenoids. RESULTS: The mean ± standard deviation ROC was 2.9 ± 0.25 cm for the glenoid, 2.3 ± 0.21 cm for the distal tibia, and 2.5 ± 0.12 cm for the humeral head. No differences were found in laterality, intraobserver, or interobserver measurements. The least-squares difference in the ROC between the glenoid and tibia was 0.57 cm, glenoid and humerus was 0.40 cm, and humerus and tibia was 0.17 cm. Only 22% of randomly paired distal tibias and glenoids had a difference in ROC of 0.3 cm or less. CONCLUSION: CT measurement of the ROC of the glenoid, distal tibia, and humeral head is reliable and reproducible. The probability of obtaining a random distal tibia allograft with a similar ROC to the glenoid is low. Obtaining ROC measurements of the injured glenoid and the distal tibia allograft specimen before use for glenoid reconstruction may be useful.


Assuntos
Cabeça do Úmero/diagnóstico por imagem , Articulação do Ombro/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Adulto , Feminino , Humanos , Cabeça do Úmero/anatomia & histologia , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tíbia/anatomia & histologia , Tomografia Computadorizada por Raios X , Adulto Jovem
9.
Proc Natl Acad Sci U S A ; 109(39): 15646-50, 2012 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-22652573

RESUMO

The effective design of an artificial photosynthetic system entails the optimization of several important interactions. Herein we report stopped-flow UV-visible (UV-vis) spectroscopy, X-ray crystallographic, density functional theory (DFT), and electrochemical kinetic studies of the Re(bipy-tBu)(CO)(3)(L) catalyst for the reduction of CO(2) to CO. A remarkable selectivity for CO(2) over H(+) was observed by stopped-flow UV-vis spectroscopy of [Re(bipy-tBu)(CO)(3)](-1). The reaction with CO(2) is about 25 times faster than the reaction with water or methanol at the same concentrations. X-ray crystallography and DFT studies of the doubly reduced anionic species suggest that the highest occupied molecular orbital (HOMO) has mixed metal-ligand character rather than being purely doubly occupied d(z)(2), which is believed to determine selectivity by favoring CO(2) (σ + π) over H(+) (σ only) binding. Electrocatalytic studies performed with the addition of Brönsted acids reveal a primary H/D kinetic isotope effect, indicating that transfer of protons to Re -CO(2) is involved in the rate limiting step. Lastly, the effects of electrode surface modification on interfacial electron transfer between a semiconductor and catalyst were investigated and found to affect the observed current densities for catalysis more than threefold, indicating that the properties of the electrode surface need to be addressed when developing a homogeneous artificial photosynthetic system.


Assuntos
Monóxido de Carbono/química , Metanol/síntese química , Processos Fotoquímicos , Fotossíntese , Rutênio/química , Água/química , Dióxido de Carbono/química , Cristalografia por Raios X , Cinética
10.
J Econ Entomol ; 108(4): 1961-71, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26470341

RESUMO

Linepithema humile (Mayr), the Argentine ant, is an invasive pest that has spread throughout the United States and is a problem in natural and managed habitats in South Carolina. Foraging patterns and the effectiveness of liquid baits for control of this pest have been studied in urban areas. However, similar studies have not been conducted in natural areas such as parks, picnic grounds, or campsites. L. humile populations can be large and widespread, making them a major nuisance pest for visitors to these natural areas. The primary objective of this study was to determine an effective distance between bait stations for control of L. humile in a natural area. A double antibody-sandwich enzyme-linked immunosorbent assay (DAS-ELISA) procedure was used to detect individual ants that consumed rabbit immunoglobin (IgG) protein for marking and tracking. In both lab and field conditions, there was a significant difference in the detection of IgG in ants fed protein marker mixed with sugar water compared with ants only fed sugar water. Additional field studies revealed that an individual ant could retain detectable levels of protein marker for 3 d and that an ant feeding on IgG containing bait could be detected over 15 m from the original bait source. Overall, we found that using liquid ant baits, with a placement of 20 m between stations, was effective in reducing L. humile numbers between April to October, 2012 in a natural park area of Lake Greenwood State Park, SC.


Assuntos
Formigas/fisiologia , Controle de Insetos/métodos , Animais , Comportamento Apetitivo , Ensaio de Imunoadsorção Enzimática , Parques Recreativos , South Carolina
11.
Poult Sci ; 94(3): 408-14, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25628420

RESUMO

This study evaluates the impact of light-emitting diode (LED), cold cathode fluorescent (CCFL), and incandescent lamps on broiler performance. Male Ross 708 broilers (n=672) were raised to 6 wk age in 8 black-out modified large colony houses, under identical intermittent lighting conditions using 4 unique types of lamps, which were gradually dimmed throughout the study. Incandescent lamps served as the control; experimental technologies tested included CCFL and 2 different LED lamps. Each technology was tested in duplicate for each of 4 trials (8 replications total per technology) conducted across the course of one year to account for seasonal variance. Live performance for each technology was evaluated using live broiler body weight (BW), weight gain, feed conversion, and mortality. Birds were removed from each house at 7, 14, 35, and 42 d to be humanely euthanized, weighed, and necropsied for allometric tissue sample analysis. Relative to the technologies tested, results indicate that birds raised under incandescent lamps had significantly higher BW by 42 d, compared to birds raised under CCFL lamps, which had poorer BW performance (P=0.03). Birds raised under both LED technologies grew to final BWs similar to those raised under incandescent light, with significant differences in neither feed conversion nor mortality.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Metabolismo Energético , Luz , Iluminação/métodos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/crescimento & desenvolvimento , Masculino , Aumento de Peso
12.
Poult Sci ; 94(3): 331-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25717091

RESUMO

This study evaluates the impact of light-emitting diodes (LEDs), cold cathode fluorescent lamps (CCFLs), and incandescent lamps on broiler welfare in response to recent interest in the agriculture industry to transition to more energy-efficient lighting technologies. Male Ross 708 broilers (n=672) were raised to 6 wk age in 8 light-tight modified large colony houses under identical intermittent lighting conditions using 4 unique types of lamps, which were gradually dimmed throughout the study. Incandescent lamps served as the control; experimental technologies tested were a CCFL, and 2 different LED lamps. Each technology was tested in duplicate for each of the 4 trials (8 replications total per technology) conducted across the course of one year to account for seasonal variance. Birds were removed from each house at days 7, 14, 35, and 42 to be humanely euthanized and weighed for necropsy evaluation and comparison of body mass. Blood collection via cardiac puncture was performed to obtain heterophil to lymphocyte (H:L) ratios for evaluation of environmental stress. Birds raised under CCFLs had significantly lower body weights (2,871 g±53) than the control (3,000±33 g) by 42 d. Birds raised under CCFLs additionally had significantly higher H:L ratios (0.68±0.06) than the control (0.53±0.03), indicating that these birds may have been chronically stressed (P=0.03). There were not significant differences in the H:L ratio between LED technologies at α=0.05. A significant age and seasonal correlation in H:L ratios was observed across all technologies, along with significant differences among birds raised under the experimental technologies. This study indicates that variation in broiler body weight and stress may be attributed in part to lighting technologies implemented in broiler houses.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Luz , Iluminação/métodos , Animais , Peso Corporal , Linfócitos , Masculino , Fotoperíodo , Estresse Fisiológico/efeitos da radiação
13.
Drug Metab Dispos ; 41(10): 1778-81, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23886700

RESUMO

Plasma-derived microRNAs (miRNAs) are being used as biomarkers, and have been associated with human liver disease and function including fibrosis, inflammation, and drug-induced liver injury. They may also be biomarkers of the drug metabolism function of the liver. In order for plasma miRNA to function as a clinical biomarker, predictable variability is necessary during processing from whole blood to plasma. The current study evaluated the variability of miRNA in whole blood stored for 0.5, 1, 2, 4, 8, and 12 hours following the blood draw under clinical conditions (room temperature) prior to the separation of the plasma. Four healthy volunteers were recruited. Blood from all subjects was collected twice. MicroRNA-16 (miR-16) and miR-223 were evaluated because many studies have shown them to be reliably present in plasma and useful for normalization. miRNA concentrations were measured by real-time polymerase chain reaction. The coefficient of variability of the cycle threshold values for subjects for miR-223 and miR-16 ranged from ∼3.6 to 6.8% and ∼1.48 to 4.1%, respectively, over the 12-hour incubation. A second blood collection was performed to determine interday variability. The coefficient of variance from the initial blood draw compared with the final blood draw for each subject ranged from 0.42 to 7.9% for miR-16 and 1.7 to 8.3% for miR-223, indicating that these miRNAs have limited interday variability. We conclude that plasma miR-16 or miR-223 concentrations are stable in whole blood at room temperature for up to 12 hours.


Assuntos
Biomarcadores/sangue , MicroRNAs/sangue , Feminino , Voluntários Saudáveis , Humanos , Hepatopatias/sangue , Masculino , Plasma/química , Temperatura
14.
Inorg Chem ; 52(5): 2484-91, 2013 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-23418912

RESUMO

Electrocatalytic properties, X-ray crystallographic studies, and infrared spectroelectrochemistry (IR-SEC) of Mn(bpy-tBu)(CO)3Br and [Mn(bpy-tBu)(CO)3(MeCN)](OTf) are reported. Addition of Brönsted acids to CO2-saturated solutions of these Mn complexes and subsequent reduction of the complexes lead to the stable and efficient production of CO from CO2. Unlike the analogous Re catalysts, these Mn catalysts require the addition of Brönsted acids for catalytic turnover. Current densities up to 30 mA/cm(2) were observed during bulk electrolysis using 5 mM Mn(bpy-tBu)(CO)3Br, 1 M 2,2,2-trifluoroethanol, and a glassy carbon working electrode. During bulk electrolysis at -2.2 V vs SCE, a TOF of 340 s(-1) was calculated for Mn(bpy-tBu)(CO)3Br with 1.4 M trifluoroethanol, corresponding to a Faradaic efficiency of 100 ± 15% for the formation of CO from CO2, with no observable production of H2. When compared to the analogous Re catalysts, the Mn catalysts operate at a lower overpotential and exhibit similar catalytic activities. X-ray crystallography of the reduced species, [Mn(bpy-tBu)(CO)3](-), shows a five-coordinate Mn center, similar to its rhenium analogue. Three distinct species were observed in the IR-SEC of Mn(bpy-tBu)(CO)3Br. These were of the parent Mn(bpy-tBu)(CO)3Br complex, the dimer [Mn(bpy-tBu)(CO)3]2, and the [Mn(bpy-tBu)(CO)3](-) anion.


Assuntos
Ácidos/química , Dióxido de Carbono/química , Monóxido de Carbono/síntese química , Manganês/química , Compostos Organometálicos/química , Rênio/química , Monóxido de Carbono/química , Catálise , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Oxirredução
15.
J Econ Entomol ; 106(6): 2448-56, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24498747

RESUMO

The plataspid Megacopta cribraria (F.), which was recently introduced to the United States, forms nuisance aggregations on the exteriors of homes when it seeks overwintering sites in the fall. Little to no published information is available on the efficacy of insecticides labeled for professional use and exterior applications on homes and other structures against this insect. In a series of three experiments, we evaluated the residual efficacy of nine insecticides incorporating pyrethroid, neonicotinoid, and oxadiazine active ingredients on surfaces composed of five exterior building materials (vinyl soffit, brick, painted and unfinished plywood, and metal) at rates labeled for use in structural perimeter applications. Pyrethroids and pyrethroid-neonicotinoid mixes were broadly effective, resulting in 100% mortality or knockdown within 24 h in most cases. The neonicotinoid dinotefuran performed similarly on metal and vinyl surfaces, but its residual efficacy was reduced on more porous brick and wood surfaces. The oxadiazine indoxacarb acted more slowly than the other materials, but its performance was maintained on porous surfaces. Overwintering adults of M. cribraria were generally susceptible to the broad-spectrum insecticides most commonly used for exterior applications to homes and other structures.


Assuntos
Heterópteros/efeitos dos fármacos , Inseticidas/toxicidade , Resíduos de Praguicidas/toxicidade , Animais , Materiais de Construção , Controle de Insetos , Espécies Introduzidas , South Carolina , Fatores de Tempo
16.
Drug Metab Dispos ; 40(4): 726-33, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22232426

RESUMO

Hepatic nuclear factor 4α (HNF4A) is a nuclear transcription factor that regulates the expression of many genes involved in drug disposition. To identify additional molecular mechanisms that regulate HNF4A, we identified microRNAs (miRNAs) that target HNF4A expression. In silico analyses suggested that HNF4A is targeted by many miRNAs. We conducted in vitro studies to validate several of these predictions. With use of an HNF4A 3'-untranslated region (UTR) luciferase reporter assay, five of six miRNAs tested significantly down-regulated (∼20-40%) the luciferase activity. In HepG2 cells, miR-34a and miR-449a also down-regulated the expression of both the HNF4A protein and an HNF4A target gene, PXR (∼30-40%). This regulation appeared without reduction in HNF4A mRNA expression, suggesting that they must be blocking HNF4A translation. Using additional bioinformatic algorithms, we identified polymorphisms that are predicted to alter the miRNA targeting of HNF4A. Luciferase assays indicated that miR-34a and miR-449a were less effective in regulating a variant (rs11574744) than the wild-type HNF4A 3'-UTR. In vivo, subjects with the variant HNF4A had lower CYP2D6 enzyme activity, although this result was not statistically significant (p = 0.16). In conclusion, our findings demonstrate strong evidence for a role of miRNAs in the regulation of HNF4A.


Assuntos
Regulação da Expressão Gênica , Fator 4 Nuclear de Hepatócito/genética , MicroRNAs/fisiologia , Polimorfismo de Nucleotídeo Único , Regiões 3' não Traduzidas/genética , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Genes Reporter , Genótipo , Células HeLa , Células Hep G2 , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Humanos , Luciferases/genética , MicroRNAs/genética , Preparações Farmacêuticas/metabolismo , Plasmídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Transfecção
17.
J Mass Spectrom ; 56(1): e4681, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33210411

RESUMO

Extracellular vesicles (EVs) convey information used in cell-to-cell interactions. Lipid analysis of EVs remains challenging because of small sample amounts available. Lipid discovery using traditional mass spectrometry platforms based on liquid chromatography and high mass resolution typically employs milligram sample amounts. We report a simple workflow for lipid profiling of EVs based on multiple reaction monitoring (MRM) profiling that uses microgram amounts of sample. After liquid-liquid extraction, individual EV samples were injected directly into the electrospray ionization (ESI) ion source at low flow rates (10 µl/min) and screened for 197 MRM transitions chosen to be a characteristic of several classes of lipids. This choice was based on a discovery experiment, which applied 1,419 MRMs associated with multiple lipid classes to a representative pooled sample. EVs isolated from 12 samples of human lymphocytes and 16 replicates from six different rat cells lines contained an estimated amount of total lipids of 326 to 805 µg. Samples showed profiles that included phosphatidylcholine (PC), sphingomyelin (SM), cholesteryl ester (CE), and ceramide (Cer) lipids, as well as acylcarnitines. The lipid profiles of human lymphocyte EVs were distinguishable using principal component and cluster analysis in terms of prior antibody and drug exposure. Lipid profiles of rat cell lines EV's were distinguishable by their tissue of origin.


Assuntos
Vesículas Extracelulares/química , Lipídeos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Humanos , Lipídeos/química , Extração Líquido-Líquido , Linfócitos/química , Linfócitos/citologia , Análise de Componente Principal , Ratos
18.
Inorg Chem ; 49(4): 1458-64, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20055470

RESUMO

The synthesis of tripbipy, a new substituted bipyridine ligand (6,6'-(2,4,6-triisopropylphenyl)-2,2'-bipyridine), and the syntheses, structures, and magnetic properties of the first coordination compounds based on this ligand are described. Tripbipy was synthesized by the Suzuki coupling of 2,4,6-triisopropylphenyl boronic acid and 6,6'-dibromo-2,2'-bipyridine. Reported here are the tripbipy complexes of five late first row transition metal chlorides (MCl(2); M = Fe, Co, Ni, Cu, Zn). Four of the complexes MCl(2)tripbipy (M = Fe, Co, Ni, Zn) crystallize in the space group P2(1)/c and are isomorphous with one solvent molecule of crystallization. The complex CuCl(2)tripbipy crystallizes in the space group P2(1)2(1)2(1) with two solvent molecules of crystallization. All MCl(2)tripbipy complexes are four coordinate and contain distorted tetrahedral metal centers. CuCl(2)tripbipy shows a pseudo Jahn-Teller distortion, and X-band electron paramagnetic resonance (EPR) in a toluene glass gives approximate g( perpendicular, parallel) values of 2.2 and 2.1. Magnetic measurements (M = Fe, Co, Ni, Cu) are consistent with high spin d(n) configurations (n = 6-9, S = 2, 3/2, 1, 1/2) tetrahedral complexes and give chi(M)T values at 300 K of 3.56, 2.10, 1.01, and 0.37 cm(3) M(-1) K, respectively.

19.
J Pediatr Psychol ; 35(1): 89-98, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19447878

RESUMO

OBJECTIVES: To describe the development and validation of a measure of negative attitudes toward physical activity and examine the association between these attitudes and self-reported physical activity among preadolescents. METHOD: A school-based sample of 382 fifth and sixth graders (mean age = 10.8) completed measures of attitudes toward physical activity and self-reported physical activity. Body mass index data for the participants was collected as a part of a standard school health assessment. Exploratory factor analysis, confirmatory factor analysis, and structural equation modeling were utilized to test the factor structure and predictive value of attitudes toward physical activity. RESULTS: Results supported the reliability and concurrent validity of the negative attitudes measure and found a significant association between negative attitudes and physical activity. Negative attitudes was found to be a stronger predictor of physical activity than positive attitudes, which have been the focus of previous research in this area. CONCLUSIONS: The results suggest that negative attitudes toward physical activity can be reliably measured and may be an important target for intervention efforts to increase physical activity among children and adolescents.


Assuntos
Atitude Frente a Saúde , Exercício Físico/fisiologia , Exercício Físico/psicologia , Atividade Motora/fisiologia , Inquéritos e Questionários/normas , Análise de Variância , Índice de Massa Corporal , Distribuição de Qui-Quadrado , Criança , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Motivação , Psicometria/normas , Reprodutibilidade dos Testes , Fatores Sexuais , Percepção Social
20.
Arthroscopy ; 26(3): 310-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20206039

RESUMO

PURPOSE: The purpose of this study was to identify the incidence of metallic suture anchor pullout after arthroscopic rotator cuff repair and determine the impact of tear size on the risk of pullout. METHODS: A retrospective review of 269 patients (550 metallic suture anchors) who underwent arthroscopic rotator cuff repair between January 2006 and January 2009 was conducted. Inclusion criteria included patients aged 18 years or older, a minimum of 6 weeks' radiographic follow-up, and the use of 1 or more metallic suture anchors for partial or complete rotator cuff repair. The mean age of the cohort at the time of surgery was 55 years (range, 29 to 86 years), and there were 189 men and 80 women. RESULTS: Early anchor pullout occurred in 6 patients (9 anchors). The overall incidence of early metallic suture anchor pullout in this cohort was 2.4% (95% confidence interval, 0.5% to 4.3%). The incidence in rotator cuff tears less than or equal to 3 cm was 0.5%, and the incidence in tears greater than 3 cm was 11%. Patients undergoing arthroscopic rotator cuff repair of a tear greater than 3 cm in size were at a significantly higher risk of having early metallic suture anchor pullout than patients undergoing repair of a smaller tear (relative risk, 22; P = .001). Among the 61 patients undergoing arthroscopic subscapularis repair, no suture anchor failures were observed at the lesser tuberosity. Of the 9 anchors that failed, 8 (89%) pulled out of the posterior aspect of the greater tuberosity. CONCLUSIONS: There is a minimal risk of suture anchor pullout in small- to medium-sized tears; however, this risk increases with larger tear sizes. We recommend routine radiographic follow-up after use of metallic anchors to ensure identification of early failure by anchor pullout. LEVEL OF EVIDENCE: Level III, prognostic case series.


Assuntos
Artroscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Manguito Rotador/cirurgia , Âncoras de Sutura/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Metais , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Fatores de Risco , Manguito Rotador/diagnóstico por imagem
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