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1.
Clin Infect Dis ; 73(Suppl 1): S58-S64, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33909063

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing remains essential for early identification and clinical management of cases. We compared the diagnostic performance of 3 specimen types for characterizing SARS-CoV-2 in infected nursing home residents. METHODS: A convenience sample of 17 residents were enrolled within 15 days of first positive SARS-CoV-2 result by real-time reverse transcription polymerase chain reaction (RT-PCR) and prospectively followed for 42 days. Anterior nasal swabs (AN), oropharyngeal swabs (OP), and saliva specimens (SA) were collected on the day of enrollment, every 3 days for the first 21 days, and then weekly for 21 days. Specimens were tested for presence of SARS-CoV-2 RNA using RT-PCR and replication-competent virus by viral culture. RESULTS: Comparing the 3 specimen types collected from each participant at each time point, the concordance of paired RT-PCR results ranged from 80% to 88%. After the first positive result, SA and OP were RT-PCR-positive for ≤48 days; AN were RT-PCR-positive for ≤33 days. AN had the highest percentage of RT-PCR-positive results (21/26 [81%]) when collected ≤10 days of participants' first positive result. Eleven specimens were positive by viral culture: 9 AN collected ≤19 days following first positive result and 2 OP collected ≤5 days following first positive result. CONCLUSIONS: AN, OP, and SA were effective methods for repeated testing in this population. More AN than OP were positive by viral culture. SA and OP remained RT-PCR-positive longer than AN, which could lead to unnecessary interventions if RT-PCR detection occurred after viral shedding has likely ceased.


Assuntos
COVID-19 , SARS-CoV-2 , Arkansas , Humanos , Casas de Saúde , RNA Viral/genética
2.
Ecotoxicol Environ Saf ; 219: 112327, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34029839

RESUMO

BACKGROUND: Studies investigating the association between pesticide exposure and colorectal cancer (CRC) risk have been inconclusive. OBJECTIVES: Investigate the association between pesticide exposure and CRC risk through a systematic literature review. METHODS: CRC has the fourth-highest rate of cancer-caused death in the US after lung cancer, breast cancer in women, and prostate cancer in men. Here we have conducted a systematic literature search on studies examining the association between any pesticide exposure and CRC risk using PubMed, MEDLINE via EBSCO host, and Embase according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. RESULTS: Following the review, 139 articles were included for qualitative evaluation. Study participants were farmers, pesticide applicators, pesticide manufacturers, spouses of pesticide applicators, farm residents, Korean veterans of the Vietnam War, rural communities, and those who consumed food with pesticide residues. The studies' results were split between those with significant positive (39 significant results) and inverse (41 significant results) associations when comparing pesticide exposure and CRC risk. DISCUSSION: From our literature review, we have identified a similar number of significant positive and inverse associations of pesticide exposure with CRC risk and therefore cannot conclude whether pesticide exposure has a positive or inverse association with CRC risk overall. However, certain pesticides such as terbufos, dicamba, trifluralin, S-ethyl dipropylthiocarbamate (EPTC), imazethapyr, chlorpyrifos, carbaryl, pendimethalin, and acetochlor are of great concern not only for their associated elevated risk of CRC, but also for the current legal usage in the United States (US). Aldicarb and dieldrin are of moderate concern for the positive associations with CRC risk, and also for the illegal usage or the detection on imported food products even though they have been banned in the US. Pesticides can linger in the soil, water, and air for weeks to years and, therefore, can lead to exposure to farmers, manufacturing workers, and those living in rural communities near these farms and factories. Approximately 60 million people in the US live in rural areas and all of the CRC mortality hotspots are within the rural communities. The CRC mortality rate is still increasing in the rural regions despite the overall decreasing of incidence and mortality of CRC elsewhere. Therefore, the results from this study on the relationship between pesticide exposure and CRC risk will help us to understand CRC health disparities.


Assuntos
Neoplasias Colorretais/epidemiologia , Fazendeiros/estatística & dados numéricos , Exposição Ocupacional/estatística & dados numéricos , Praguicidas/análise , Adulto , Feminino , Herbicidas/análise , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Resíduos de Praguicidas/análise
3.
Biochem Biophys Res Commun ; 498(3): 597-602, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29522717

RESUMO

Synthetic cannabinoids (SCBs), synonymous with 'K2', 'Spice' or 'synthetic marijuana', are psychoactive drugs of abuse that frequently result in clinical effects and toxicity more severe than those classically associated with Δ9-tetrahydrocannabinol such as extreme agitation, hallucinations, supraventricular tachycardia, syncope, and seizures. JWH-018 is one of the earliest compounds identified in various SCB products, and our laboratory previously demonstrated that JWH-018 undergoes extensive metabolism by cytochromes P450 (P450), binds to, and activates cannabinoid receptors (CBRs). The major enzyme involved in the metabolism of JWH-018 is CYP2C9, a highly polymorphic enzyme found largely in the intestines and liver, with *1 being designated as the wild type, and *2 and *3 as the two most common variants. Three different major products have been identified in human urine and plasma: JWH-018 (ω)-OH, JWH-018 (ω-1)-OH(R), and JWH-018 (ω-1)-OH(S). The (ω-1)-OH metabolite of JWH-018 is a chiral molecule, and is thus designated as either (ω-1)-OH(R) or (ω-1)-OH(S). Here, in vitro enzyme kinetic assays performed with human recombinant CYP2C9 variants (*1, *2, and *3) revealed that oxidative metabolism by CYP2C9*3 resulted in significantly less formation of (ω)-OH and (ω-1)-OH metabolites. Surprisingly, CYP2C9*2 was roughly 3.6-fold more efficient as the CYP2C9*1 enzyme based on Vmax/Km, increasing the rate of JWH-018 metabolism and allowed for a much more rapid elimination. These results suggest that genetic polymorphisms of P450 enzymes result in the production of varying levels of biologically active JWH-018 metabolites in some individuals, offering a mechanistic explanation for the diverse clinical toxicity often observed following JWH-018 abuse.


Assuntos
Citocromo P-450 CYP2C9/metabolismo , Drogas Ilícitas/metabolismo , Indóis/metabolismo , Naftalenos/metabolismo , Citocromo P-450 CYP2C9/genética , Humanos , Cinética , Redes e Vias Metabólicas , Oxirredução , Polimorfismo Genético , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transtornos Relacionados ao Uso de Substâncias/genética , Transtornos Relacionados ao Uso de Substâncias/metabolismo
4.
Anal Chem ; 86(3): 1760-6, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24354295

RESUMO

Opioid abuse involving emerging opioid compounds is a growing public health problem, which was highlighted recently by cases of human morbidity and mortality linked to acetyl fentanyl abuse. Unfortunately, the lack of information available on the toxicology and metabolism of acetyl fentanyl precludes its detection in human samples. The following study was conducted to test a new analytical procedure for the simultaneous quantification of acetyl fentanyl and its predicted metabolite, acetyl norfentanyl, in human urine. Metabolic reference standards and deuterium-labeled internal standards were synthesized for use in an assay that coupled solid-phase extraction (SPE) with liquid chromatography-tandem mass spectrometry (LC-MS/MS). The accuracy (% Relative Error <5%) and inter- and intrarun precision (%CV <20%) of this new method resulted in low levels of quantification (∼1 ng/mL). Similar results were obtained using liquid chromatography columns manufactured with phenyl-hexyl and biphenyl stationary phases (r(2) > 0.98). Preliminary human liver microsomal and in vivo rodent studies demonstrated that acetyl fentanyl is metabolized by cytochrome P450s to acetyl norfentanyl. Urine samples from rats treated with a toxic dose of acetyl fentanyl contained high concentrations of acetyl fentanyl and acetyl norfentanyl. Further toxicokinetic studies are required to fully elucidate the metabolic pathways responsible for acetyl fentanyl detoxification and excretion.


Assuntos
Analgésicos Opioides/urina , Fentanila/análogos & derivados , Urinálise/métodos , Analgésicos Opioides/metabolismo , Animais , Cromatografia Líquida , Sistema Enzimático do Citocromo P-450/metabolismo , Fentanila/metabolismo , Fentanila/urina , Humanos , Masculino , Ratos , Espectrometria de Massas em Tandem
5.
Anal Chem ; 85(19): 9390-9, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23987522

RESUMO

Designer synthetic cannabinoids like JWH-018 and AM2201 have unique clinical toxicity. Cytochrome-P450-mediated metabolism of each leads to the generation of pharmacologically active (ω)- and (ω-1)-monohydroxyl metabolites that retain high affinity for cannabinoid type-1 receptors, exhibit Δ(9)-THC-like effects in rodents, and are conjugated with glucuronic acid prior to excretion in human urine. Previous studies have not measured the contribution of the specific (ω-1)-monohydroxyl enantiomers in human metabolism and toxicity. This study uses a chiral liquid chromatography-tandem mass spectroscopy approach (LC-MS/MS) to quantify each specific enantiomer and other nonchiral, human metabolites of JWH-018 and AM2201 in human urine. The accuracy (average % RE = 18.6) and reproducibility (average CV = 15.8%) of the method resulted in low-level quantification (average LLQ = 0.99 ng/mL) of each metabolite. Comparisons with a previously validated nonchiral method showed strong correlation between the two approaches (average r(2) = 0.89). Pilot data from human urine samples demonstrate enantiospecific excretion patterns. The (S)-isomer of the JWH-018-(ω-1)-monohydroxyl metabolite was predominantly excreted (>87%) in human urine as the glucuronic acid conjugate, whereas the relative abundance of the corresponding AM2201-(ω-1)-metabolite was low (<5%) and did not demonstrate enantiospecificity (approximate 50:50 ratio of each enantiomer). The new chiral method provides a comprehensive, targeted metabolomic approach for studying the human metabolism of JWH-018 and AM2201. Preliminary evaluations of specific enantiomeric contributions support the use of this approach in future studies designed to understand the pharmacokinetic properties of JWH-018 and/or AM2201.


Assuntos
Indóis/metabolismo , Metabolômica , Naftalenos/metabolismo , Cromatografia Líquida , Humanos , Indóis/farmacocinética , Indóis/urina , Estrutura Molecular , Naftalenos/farmacocinética , Naftalenos/urina , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Distribuição Tecidual
6.
Am J Pathol ; 180(2): 505-16, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22119717

RESUMO

Acute kidney injury is a frequent and serious complication of sepsis. To better understand the development of sepsis-induced acute kidney injury, we performed the first time-dependent studies to document changes in renal hemodynamics and oxidant generation in the peritubular microenvironment using the murine cecal ligation and puncture (CLP) model of sepsis. CLP caused an increase in renal capillary permeability at 2 hours, followed by decreases in mean arterial pressure, renal blood flow (RBF), and renal capillary perfusion at 4 hours, which were sustained through 18 hours. The decline in hemodynamic parameters was associated with hypoxia and oxidant generation in the peritubular microenvironment and a decrease in glomerular filtration rate. The role of oxidants was assessed using the superoxide dismutase mimetic/peroxynitrite scavenger MnTMPyP [Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin]. At 10 mg/kg administered 6 hours after CLP, MnTMPyP did not alter blood pressure, but blocked superoxide and peroxynitrite generation, reversed the decline in RBF, capillary perfusion, and glomerular filtration rate, preserved tubular architecture, and increased 48-hour survival. However, MnTMPyP administered at CLP did not prevent capillary permeability or the decrease in RBF and capillary perfusion, which suggests that these early events are not mediated by oxidants. These data demonstrate that renal hemodynamic changes occur early after sepsis and that targeting the later oxidant generation can break the cycle of injury and enable the microcirculation and renal function to recover.


Assuntos
Injúria Renal Aguda/prevenção & controle , Microambiente Celular/fisiologia , Sequestradores de Radicais Livres/farmacologia , Metaloporfirinas/farmacologia , Estresse Oxidativo/fisiologia , Sepse/fisiopatologia , Injúria Renal Aguda/fisiopatologia , Animais , Pressão Sanguínea/fisiologia , Capilares/fisiologia , Permeabilidade Capilar/fisiologia , Hipóxia Celular/fisiologia , Células Epiteliais/fisiologia , Taxa de Filtração Glomerular/fisiologia , Frequência Cardíaca/fisiologia , Ligadura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nitratos/metabolismo , Nitritos/metabolismo , Oxirredução , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Circulação Renal/fisiologia , Superóxido Dismutase/metabolismo
7.
Kidney Int ; 81(4): 370-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21975863

RESUMO

The mortality rate of patients who develop acute kidney injury during sepsis nearly doubles. The effectiveness of therapy is hampered because it is usually initiated only after the onset of symptoms. As renal microvascular failure during sepsis is correlated with the generation of reactive nitrogen species, the therapeutic potential of resveratrol, a polyphenol vasodilator that is also capable of scavenging reactive nitrogen species, was investigated using the cecal ligation and puncture (CLP) murine model of sepsis-induced acute kidney injury. Resveratrol when given at 5.5 h following CLP reversed the decline in cortical capillary perfusion, assessed by intravital microscopy, at 6 h in a dose-dependent manner. Resveratrol produced the greatest improvement in capillary perfusion and increased renal blood flow and the glomerular filtration rate without raising systemic pressure. A single dose at 6 h after CLP was unable to improve renal microcirculation assessed at 18 h; however, a second dose at 12 h significantly improved microcirculation and decreased the levels of reactive nitrogen species in tubules, while improving renal function. Moreover, resveratrol given at 6, 12, and 18 h significantly improved survival. Hence, resveratrol may have a dual mechanism of action to restore the renal microcirculation and scavenge reactive nitrogen species, thus protecting the tubular epithelium even when administered after the onset of sepsis.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Antioxidantes/uso terapêutico , Rim/fisiopatologia , Microcirculação/efeitos dos fármacos , Sepse/sangue , Estilbenos/uso terapêutico , Injúria Renal Aguda/sangue , Injúria Renal Aguda/fisiopatologia , Animais , Antioxidantes/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Epitélio/efeitos dos fármacos , Epitélio/patologia , Taxa de Filtração Glomerular/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Rim/irrigação sanguínea , Rim/patologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Nitrogênio/sangue , Resveratrol , Sepse/complicações , Estilbenos/farmacologia , Análise de Sobrevida , Fatores de Tempo , Vasodilatadores/farmacologia , Vasodilatadores/uso terapêutico
8.
Drug Metab Dispos ; 40(11): 2174-84, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22904561

RESUMO

Abuse of synthetic cannabinoids (SCs), such as [1-naphthalenyl-(1-pentyl-1H-indol-3-yl]-methanone (JWH-018) and [1-(5-fluoropentyl)-1H-indol-3-yl]-1-naphthalenyl-methanone (AM2201), is increasing at an alarming rate. Although very little is known about the metabolism and toxicology of these popular designer drugs, mass spectrometric analysis of human urine specimens after JWH-018 and AM2201 exposure identified monohydroxylated and carboxylated derivatives as major metabolites. The present study extends these initial findings by testing the hypothesis that JWH-018 and its fluorinated counterpart AM2201 are subject to cytochrome P450 (P450)-mediated oxidation, forming potent hydroxylated metabolites that retain significant affinity and activity at the cannabinoid 1 (CB(1)) receptor. Kinetic analysis using human liver microsomes and recombinant human protein identified CYP2C9 and CYP1A2 as major P450s involved in the oxidation of the JWH-018 and AM2201. In vitro metabolite formation mirrored human urinary metabolic profiles, and each of the primary enzymes exhibited high affinity (K(m) = 0.81-7.3 µM) and low to high reaction velocities (V(max) = 0.0053-2.7 nmol of product · min(-1) · nmol protein(-1)). The contribution of CYP2C19, 2D6, 2E1, and 3A4 in the hepatic metabolic clearance of these synthetic cannabinoids was minimal (f(m) = <0.2). In vitro studies demonstrated that the primary metabolites produced in humans display high affinity and intrinsic activity at the CB(1) receptor, which was attenuated by the CB(1) receptor antagonist (6aR,10aR)-3-(1-methanesulfonylamino-4-hexyn-6-yl)-6a,7,10,10a-tetrahydro-6,6,9-trimethyl-6H-dibenzo[b,d]pyran (O-2050). Results from the present study provide critical, missing data related to potential toxicological properties of "K2" parent compounds and their human metabolites, including mechanism(s) of action at cannabinoid receptors.


Assuntos
Canabinoides/farmacocinética , Sistema Enzimático do Citocromo P-450/metabolismo , Drogas Ilícitas/farmacocinética , Receptor CB1 de Canabinoide/metabolismo , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Encéfalo/metabolismo , Canabinoides/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2C9 , Dronabinol/análogos & derivados , Dronabinol/farmacologia , Humanos , Hidroxilação , Drogas Ilícitas/metabolismo , Indóis/metabolismo , Cinética , Ligantes , Fígado/metabolismo , Espectrometria de Massas/métodos , Camundongos , Microssomos Hepáticos/metabolismo , Naftalenos/metabolismo , Oxirredução , Ligação Proteica , Piranos/farmacologia , Receptor CB1 de Canabinoide/antagonistas & inibidores
9.
Chem Res Toxicol ; 25(4): 825-7, 2012 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-22404317

RESUMO

Recently, hydroxylated metabolites of JWH-018, a synthetic cannabinoid found in many K2/Spice preparations, have been shown to retain affinity and activity for cannabinoid type 1 receptors (CB1Rs). The activity of glucuronidated metabolites of JWH-018 is not known; hence, this study investigated the affinity and activity of a major metabolite, JWH-018-N-(5-hydroxypentyl) ß-D-glucuronide (018-gluc), for CB1Rs. The 018-gluc binds CB1Rs (K(i) = 922 nM), has no effect on G-protein activity, but antagonizes JWH-018 activity at CB1Rs. The data suggests that hydroxylation by cytochrome P450s and subsequent glucuronidation by UDP-glucuronosyltransferases produces a metabolite, 018-gluc, which possesses antagonistic activity at CB1Rs.


Assuntos
Indóis/metabolismo , Naftalenos/metabolismo , Receptor CB1 de Canabinoide/antagonistas & inibidores , Sistema Enzimático do Citocromo P-450/metabolismo , Glucuronídeos/química , Glucuronosiltransferase/metabolismo , Humanos , Hidroxilação , Indóis/química , Indóis/toxicidade , Naftalenos/química , Naftalenos/toxicidade , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Receptor CB1 de Canabinoide/metabolismo
10.
Xenobiotica ; 42(2): 139-56, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21970716

RESUMO

RATIONALE: The therapeutic promise of trans-resveratrol (tRes) is limited by poor bioavailability following rapid metabolism. We hypothesise that trans-arachidin-1 (tA1) and trans-arachidin-3 (tA3), peanut hairy root-derived isoprenylated analogs of tRes, will exhibit slower metabolism/enhanced bioavailability and retain biological activity via cannabinoid receptor (CBR) binding relative to their non-prenylated parent compounds trans-piceatannol (tPice) and tRes, respectively. RESULTS: The activities of eight human UDP-glucuronosyltransferases (UGTs) toward these compounds were evaluated. The greatest activity was observed for extrahepatic UGTs 1A10 and 1A7, followed by hepatic UGTs 1A1 and 1A9. Importantly, an additional isoprenyl and/or hydroxyl group in tA1 and tA3 slowed overall glucuronidation. CBR binding studies demonstrated that all analogs bound to CB1Rs with similar affinities (5-18 µM); however, only tA1 and tA3 bound appreciably to CB2Rs. Molecular modelling studies confirmed that the isoprenyl moiety of tA1 and tA3 improved binding affinity to CB2Rs. Finally, although tA3 acted as a competitive CB1R antagonist, tA1 antagonised CB1R agonists by both competitive and non-competitive mechanisms. CONCLUSIONS: Prenylated stilbenoids may be preferable alternatives to tRes due to increased bioavailability via slowed metabolism. Similar structural analogs might be developed as novel CB therapeutics for obesity and/or drug dependency.


Assuntos
Glucuronosiltransferase/química , Hemiterpenos/farmacologia , Receptores de Canabinoides/química , Estilbenos/química , Estilbenos/farmacologia , Animais , Ligação Competitiva , Disponibilidade Biológica , Células CHO , Cromatografia Líquida de Alta Pressão , Cricetinae , Hemiterpenos/química , Hemiterpenos/farmacocinética , Humanos , Cinética , Espectrometria de Massas , Desintoxicação Metabólica Fase II , Modelos Moleculares , Prenilação , Proteínas Recombinantes/química , Resveratrol , Estilbenos/farmacocinética
11.
Infect Control Hosp Epidemiol ; 43(11): 1610-1617, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34802478

RESUMO

OBJECTIVE: To characterize and compare severe acute respiratory coronavirus virus 2 (SARS-CoV-2)-specific immune responses in plasma and gingival crevicular fluid (GCF) from nursing home residents during and after natural infection. DESIGN: Prospective cohort. SETTING: Nursing home. PARTICIPANTS: SARS-CoV-2-infected nursing home residents. METHODS: A convenience sample of 14 SARS-CoV-2-infected nursing home residents, enrolled 4-13 days after real-time reverse transcription polymerase chain reaction diagnosis, were followed for 42 days. After diagnosis, plasma SARS-CoV-2-specific pan-Immunoglobulin (Ig), IgG, IgA, IgM, and neutralizing antibodies were measured at 5 time points, and GCF SARS-CoV-2-specific IgG and IgA were measured at 4 time points. RESULTS: All participants demonstrated immune responses to SARS-CoV-2 infection. Among 12 phlebotomized participants, plasma was positive for pan-Ig and IgG in all 12 participants. Neutralizing antibodies were positive in 11 participants; IgM was positive in 10 participants, and IgA was positive in 9 participants. Among 14 participants with GCF specimens, GCF was positive for IgG in 13 participants and for IgA in 12 participants. Immunoglobulin responses in plasma and GCF had similar kinetics; median times to peak antibody response were similar across specimen types (4 weeks for IgG; 3 weeks for IgA). Participants with pan-Ig, IgG, and IgA detected in plasma and GCF IgG remained positive throughout this evaluation, 46-55 days after diagnosis. All participants were viral-culture negative by the first detection of antibodies. CONCLUSIONS: Nursing home residents had detectable SARS-CoV-2 antibodies in plasma and GCF after infection. Kinetics of antibodies detected in GCF mirrored those from plasma. Noninvasive GCF may be useful for detecting and monitoring immunologic responses in populations unable or unwilling to be phlebotomized.


Assuntos
COVID-19 , Pneumonia , Humanos , SARS-CoV-2 , Formação de Anticorpos , Líquido do Sulco Gengival/química , Imunoglobulina M , Anticorpos Antivirais , Arkansas , Estudos Prospectivos , COVID-19/diagnóstico , Imunoglobulina A/análise , Imunoglobulina G , Anticorpos Neutralizantes , Casas de Saúde
12.
Am J Physiol Renal Physiol ; 301(1): F209-17, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21511700

RESUMO

Sepsis is a leading cause of acute kidney injury (AKI) and mortality in children. Understanding the development of pediatric sepsis and its effects on the kidney are critical in uncovering new therapies. The goal of this study was to characterize the development of sepsis-induced AKI in the clinically relevant cecal ligation and puncture (CLP) model of peritonitis in rat pups 17-18 days old. CLP produced severe sepsis demonstrated by time-dependent increase in serum cytokines, NO, markers of multiorgan injury, and renal microcirculatory hypoperfusion. Although blood pressure and heart rate remained unchanged after CLP, renal blood flow (RBF) was decreased 61% by 6 h. Renal microcirculatory analysis showed the number of continuously flowing cortical capillaries decreased significantly from 69 to 48% by 6 h with a 66% decrease in red blood cell velocity and a 57% decline in volumetric flow. The progression of renal microcirculatory hypoperfusion was associated with peritubular capillary leakage and reactive nitrogen species generation. Sham adults had higher mean arterial pressure (118 vs. 69 mmHg), RBF (4.2 vs. 1.1 ml·min(-1)·g(-1)), and peritubular capillary velocity (78% continuous flowing capillaries vs. 69%) compared with pups. CLP produced a greater decrease in renal microcirculation in pups, supporting the notion that adult models may not be the most appropriate for studying pediatric sepsis-induced AKI. Lower RBF and reduced peritubular capillary perfusion in the pup suggest the pediatric kidney may be more susceptible to AKI than would be predicted using adults models.


Assuntos
Injúria Renal Aguda/fisiopatologia , Hemodinâmica/fisiologia , Circulação Renal/fisiologia , Sepse/fisiopatologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/patologia , Animais , Animais Recém-Nascidos , Biomarcadores/sangue , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Permeabilidade Capilar/fisiologia , Ceco/fisiologia , Hidratação , Hipotermia/etiologia , Hipotermia/fisiopatologia , Imuno-Histoquímica , Rim/patologia , Ligadura , Masculino , Microcirculação/fisiologia , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/fisiopatologia , Peritonite/etiologia , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sepse/complicações , Telemetria
13.
Open Forum Infect Dis ; 8(3): ofab048, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33723510

RESUMO

BACKGROUND: To estimate the infectious period of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in older adults with underlying conditions, we assessed duration of coronavirus disease 2019 (COVID-19) symptoms, reverse-transcription polymerase chain reaction (RT-PCR) positivity, and culture positivity among nursing home residents. METHODS: We enrolled residents within 15 days of their first positive SARS-CoV-2 test (diagnosis) at an Arkansas facility from July 7 to 15, 2020 and instead them for 42 days. Every 3 days for 21 days and then weekly, we assessed COVID-19 symptoms, collected specimens (oropharyngeal, anterior nares, and saliva), and reviewed medical charts. Blood for serology was collected on days 0, 6, 12, 21, and 42. Infectivity was defined by positive culture. Duration of culture positivity was compared with duration of COVID-19 symptoms and RT-PCR positivity. Data were summarized using measures of central tendency, frequencies, and proportions. RESULTS: We enrolled 17 of 39 (44%) eligible residents. Median participant age was 82 years (range, 58-97 years). All had ≥3 underlying conditions. Median duration of RT-PCR positivity was 22 days (interquartile range [IQR], 8-31 days) from diagnosis; median duration of symptoms was 42 days (IQR, 28-49 days). Of 9 (53%) participants with any culture-positive specimens, 1 (11%) severely immunocompromised participant remained culture-positive 19 days from diagnosis; 8 of 9 (89%) were culture-positive ≤8 days from diagnosis. Seroconversion occurred in 12 of 12 (100%) surviving participants with ≥1 blood specimen; all participants were culture-negative before seroconversion. CONCLUSIONS: Duration of infectivity was considerably shorter than duration of symptoms and RT-PCR positivity. Severe immunocompromise may prolong SARS-CoV-2 infectivity. Seroconversion indicated noninfectivity in this cohort.

14.
J Pharmacol Exp Ther ; 330(1): 31-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19359525

RESUMO

The dietary polyphenols trans-resveratrol [5-[(1E)-2-(4-hydroxyphenyl)ethenyl]-1,3-benzenediol; found in red wine] and curcumin [1,7-bis(4-hydroxy-3-methoxyphenyl)-1E,6E-heptadiene-3,5-dione] (found in curry powders) exert anti-inflammatory and antioxidant effects via poorly defined mechanisms. It is interesting that cannabinoids, derived from the marijuana plant (Cannabis sativa), produce similar protective effects via CB1 and CB2 receptors. We examined whether trans-resveratrol, curcumin, and ASC-J9 [1,7-bis(3,4-dimethoxyphenyl)-5-hydroxy-1E,4E,6E-heptatriene-3-one] (a curcumin analog) act as ligands at cannabinoid receptors. All three bind to human (h) CB1 and mouse CB1 receptors with nanomolar affinities, displaying only micromolar affinities for hCB2 receptors. Characteristic of inverse agonists, the polyphenols inhibit basal G-protein activity in membranes prepared from Chinese hamster ovary (CHO)-hCB1 cells or mouse brain that is reversed by a neutral CB1 antagonist. Furthermore, they competitively antagonize G-protein activation produced by a CB1 agonist. In intact CHO-hCB1 cells, the polyphenols act as neutral antagonists, producing no effect when tested alone, whereas competitively antagonizing CB1 agonist mediated inhibition of adenylyl cyclase activity. Confirming their neutral antagonist profile in cells, the polyphenols similarly attenuate stimulation of adenylyl cyclase activity produced by a CB1 inverse agonist. In mice, the polyphenols dose-dependently reverse acute hypothermia produced by a CB1 agonist. Upon repeated administration, the polyphenols also reduce body weight in mice similar to that produced by a CB1 antagonist/inverse agonist. Finally, trans-resveratrol and curcumin share common structural motifs with other known cannabinoid receptor ligands. Collectively, we suggest that trans-resveratrol and curcumin act as antagonists/inverse agonists at CB1 receptors at dietary relevant concentrations. Therefore, these polyphenols and their derivatives might be developed as novel, nontoxic CB1 therapeutics for obesity and/or drug dependence.


Assuntos
Curcumina/metabolismo , Flavonoides/metabolismo , Fenóis/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Estilbenos/metabolismo , Animais , Células CHO , Cricetinae , Cricetulus , Feminino , Humanos , Masculino , Camundongos , Polifenóis , Ligação Proteica/fisiologia , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Resveratrol
15.
Sci Rep ; 9(1): 3938, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30850706

RESUMO

Community-associated acquisition of extended-spectrum beta-lactamase- (ESBL) and carbapenemase-producing Enterobacteriaceae has significantly increased in recent years, necessitating greater inquiry into potential exposure routes, including food and water sources. In high-income countries, drinking water is often neglected as a possible source of community exposure to antibiotic-resistant organisms. We screened coliform-positive tap water samples (n = 483) from public and private water systems in six states of the United States for blaCTX-M, blaSHV, blaTEM, blaKPC, blaNDM, and blaOXA-48-type genes by multiplex PCR. Positive samples were subcultured to isolate organisms harboring ESBL or carbapenemase genes. Thirty-one samples (6.4%) were positive for blaCTX-M, ESBL-type blaSHV or blaTEM, or blaOXA-48-type carbapenemase genes, including at least one positive sample from each state. ESBL and blaOXA-48-type Enterobacteriaceae isolates included E. coli, Kluyvera, Providencia, Klebsiella, and Citrobacter species. The blaOXA-48-type genes were also found in non-fermenting Gram-negative species, including Shewanella, Pseudomonas and Acinetobacter. Multiple isolates were phenotypically non-susceptible to third-generation cephalosporin or carbapenem antibiotics. These findings suggest that tap water in high income countries could serve as an important source of community exposure to ESBL and carbapenemase genes, and that these genes may be disseminated by non-Enterobacteriaceae that are not detected as part of standard microbiological water quality testing.


Assuntos
Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Água Potável/microbiologia , Enterobacteriaceae/genética , beta-Lactamases/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/enzimologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Genes Bacterianos/genética , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase Multiplex , Estados Unidos
16.
Int J Anal Chem ; 2015: 359629, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25873967

RESUMO

National Oceanic and Atmospheric Administration (NOAA) Method NMFS-NWFSC-59 2004 is currently used to quantitatively analyze seafood for polycyclic aromatic hydrocarbon (PAH) contamination, especially following events such as the Deepwater Horizon oil rig explosion that released millions of barrels of crude oil into the Gulf of Mexico. This method has limited throughput capacity; hence, alternative methods are necessary to meet analytical demands after such events. Stir bar sorptive extraction (SBSE) is an effective technique to extract trace PAHs in water and the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction strategy effectively extracts PAHs from complex food matrices. This study uses SBSE to concentrate PAHs and eliminate matrix interference from QuEChERS extracts of seafood, specifically oysters, fish, and shrimp. This method provides acceptable recovery (65-138%) linear calibrations and is sensitive (LOD = 0.02 ppb, LOQ = 0.06 ppb) while providing higher throughput and maintaining equivalency between NOAA 2004 as determined by analysis of NIST SRM 1974b mussel tissue.

17.
J Pharmacol Exp Ther ; 331(3): 1147, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19940110
18.
Forensic Sci Int ; 233(1-3): 416-22, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24314548

RESUMO

New designer drugs such as K2, Spice, and "bath salts" present a formidable challenge for law enforcement and public health officials. The following report summarizes a three-year study of 1320 law enforcement cases involving over 3000 products described as vegetable material, powders, capsules, tablets, blotter paper, or drug paraphernalia. All items were seized in Arkansas from January 2010 through December 2012 and submitted to the Arkansas State Crime Laboratory for analysis. The geographical distribution of these seizures co-localized in areas with higher population, colleges, and universities. Validated forensic testing procedures confirmed the presence of 26 synthetic cannabinoids, 12 designer stimulants, and 5 hallucinogenic-like drugs regulated by the Synthetic Drug Prevention Act of 2012 and other state statutes. Analysis of paraphernalia suggests that these drugs are commonly used concomitantly with other drugs of abuse including marijuana, MDMA, and methamphetamine. Exact designer drug compositions were unpredictable and often formulated with multiple agents, but overall, the synthetic cannabinoids were significantly more prevalent than all the other designer drugs detected. The synthetic cannabinoids JWH-018, AM2201, JWH-122, JWH-210, and XLR11 were most commonly detected in green vegetable material and powder products. The designer stimulants methylenedioxypyrovalerone (MDPV), 3,4-methylenedioxy-N-methylcathinone (methylone), and α-methylamino-valerophenone (pentedrone) were commonly detected in tablets, capsules, and powders. Hallucinogenic drugs were rarely detected, but generally found on blotter paper products. Emerging designer drug products remain a significant problem and continued surveillance is needed to protect public health.


Assuntos
Drogas Desenhadas/química , Benzodioxóis/química , Canabinoides/química , Cápsulas , Estimulantes do Sistema Nervoso Central/química , Dronabinol/química , Alucinógenos/química , Humanos , Indóis/química , Metanfetamina/análogos & derivados , Metanfetamina/química , Metilaminas/química , Estrutura Molecular , Naftalenos/química , Papel , Pentanonas/química , Pós , Pirrolidinas/química , Transtornos Relacionados ao Uso de Substâncias , Comprimidos , Catinona Sintética
19.
Prog Neuropsychopharmacol Biol Psychiatry ; 39(2): 234-43, 2012 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-22561602

RESUMO

"K2" and "Spice" drugs (collectively hereafter referred to as Spice) represent a relatively new class of designer drugs that have recently emerged as popular alternatives to marijuana, otherwise characterized as "legal highs". These drugs are readily available on the Internet and sold in many head shops and convenience stores under the disguise of innocuous products like herbal blends, incense, or air fresheners. Although package labels indicate "not for human consumption", the number of intoxicated people presenting to emergency departments is dramatically increasing. The lack of validated and standardized human testing procedures and an endless supply of potential drugs of abuse are primary reasons why researchers find it difficult to fully characterize clinical consequences associated with Spice. While the exact chemical composition and toxicology of Spice remains to be determined, there is mounting evidence identifying several synthetic cannabinoids as causative agents responsible for psychoactive and adverse physical effects. This review provides updates of the legal status of common synthetic cannabinoids detected in Spice and analytical procedures used to test Spice products and human specimens collected under a variety of clinical circumstances. The pharmacological and toxicological consequences of synthetic cannabinoid abuse are also reviewed to provide a future perspective on potential short- and long-term implications.


Assuntos
Canabinoides/farmacologia , Canabinoides/toxicidade , Drogas Desenhadas/farmacologia , Drogas Desenhadas/toxicidade , Animais , Canabinoides/análise , Drogas Desenhadas/análise , Usuários de Drogas/psicologia , Usuários de Drogas/estatística & dados numéricos , Controle de Medicamentos e Entorpecentes/legislação & jurisprudência , Humanos , Indóis/análise , Indóis/farmacologia , Indóis/toxicidade , Naftalenos/análise , Naftalenos/farmacologia , Naftalenos/toxicidade
20.
Neuropharmacology ; 63(5): 905-15, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22771770

RESUMO

Mu-opioid and CB1-cannabinoid agonists produce analgesia; however, adverse effects limit use of drugs in both classes. Additive or synergistic effects resulting from concurrent administration of low doses of mu- and CB1-agonists may produce analgesia with fewer side effects. Synergism potentially results from interaction between mu-opioid receptors (MORs) and CB1 receptors (CB1Rs). AM-251 and rimonabant are CB1R antagonist/inverse agonists employed to validate opioid-cannabinoid interactions, presumed to act selectively at CB1Rs. Therefore, the potential for direct action of these antagonists at MORs is rarely considered. This study determined if AM-251 and/or rimonabant directly bind and modulate the function of MORs. Surprisingly, AM-251 and rimonabant, but not a third CB1R inverse agonist AM-281, bind with mid-nanomolar affinity to human MORs with a rank order of affinity (K(i)) of AM-251 (251 nM) > rimonabant (652 nM) > AM281 (2135 nM). AM-251 and rimonabant, but not AM-281, also competitively antagonize morphine induced G-protein activation in CHO-hMOR cell homogenates (K(b) = 719 or 1310 nM, respectively). AM-251 and rimonabant block morphine inhibition of cAMP production, while only AM-251 elicits cAMP rebound in CHO-hMOR cells chronically exposed to morphine. AM-251 and rimonabant (10 mg/kg) attenuate morphine analgesia, whereas the same dose of AM-281 produces little effect. Therefore, in addition to high CB1R affinity, AM-251 and rimonabant bind to MORs with mid-nanomolar affinity and at higher doses may affect morphine analgesia via direct antagonism at MORs. Such CB1-independent of these antagonists effects may contribute to reported inconsistencies when CB1/MOR interactions are examined via pharmacological methods in CB1-knockout versus wild-type mice.


Assuntos
Analgésicos não Narcóticos/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Antagonistas de Entorpecentes/farmacologia , Piperidinas/farmacologia , Pirazóis/farmacologia , Receptor CB1 de Canabinoide/agonistas , Receptores Opioides mu/antagonistas & inibidores , Analgésicos não Narcóticos/efeitos adversos , Analgésicos não Narcóticos/metabolismo , Analgésicos não Narcóticos/uso terapêutico , Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/antagonistas & inibidores , Analgésicos Opioides/metabolismo , Analgésicos Opioides/farmacologia , Animais , Ligação Competitiva , Células CHO , Agonistas de Receptores de Canabinoides/efeitos adversos , Agonistas de Receptores de Canabinoides/metabolismo , Agonistas de Receptores de Canabinoides/uso terapêutico , Cricetinae , Cricetulus , Agonismo Inverso de Drogas , Humanos , Cinética , Camundongos , Camundongos Endogâmicos , Morfolinas/efeitos adversos , Morfolinas/metabolismo , Morfolinas/farmacologia , Antagonistas de Entorpecentes/efeitos adversos , Antagonistas de Entorpecentes/metabolismo , Antagonistas de Entorpecentes/uso terapêutico , Piperidinas/efeitos adversos , Piperidinas/metabolismo , Piperidinas/uso terapêutico , Pirazóis/efeitos adversos , Pirazóis/metabolismo , Pirazóis/uso terapêutico , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/genética , Receptor CB2 de Canabinoide/metabolismo , Receptores Opioides mu/agonistas , Receptores Opioides mu/genética , Receptores Opioides mu/metabolismo , Proteínas Recombinantes/agonistas , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Rimonabanto
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