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1.
NPJ Aging ; 10(1): 7, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302501

RESUMO

Reversal or mitigation against an age-related decline in NAD+ has likely benefits, and this premise has driven academic and commercial endeavour to develop dietary supplements that achieve this outcome. We used a systems-based approach to improve on current supplements by targeting multiple points in the NAD+ salvage pathway. In a double-blind, randomised, crossover trial, the supplement - Nuchido TIME+® (NT) - increased NAD+ concentration in whole blood. This was associated with an increase in SIRT1 and an increase in nicotinamide phosphoribosyltransferase (NAMPT) in peripheral blood mononucleocytes, lower concentrations of pro-inflammatory cytokines in plasma, including a reduction in interleukin 2 (IL2), a reduction in glycated serum protein and a shift in the glycosylation profile of immunoglobulin G (IgG) toward a younger biological age, all of which are likely to promote a healthier ageing trajectory.

2.
J Card Fail ; 29(1): 56-66, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36332900

RESUMO

BACKGROUND: Therapy guided by pulmonary artery (PA) pressure monitoring reduces PA pressures and heart failure hospitalizations (HFH) during the first year, but the durability of efficacy and safety through 2 years is not known. METHODS AND RESULTS: The CardioMEMS Post-Approval Study investigated whether benefit and safety were generalized and sustained. Enrollment at 104 centers in the United States included 1200 patients with NYHA Class III symptoms on recommended HF therapies with prior HFH. Therapy was adjusted toward PA diastolic pressure 8-20 mmHg. Intervention frequency and PA pressure reduction were most intense during first 90 days, with sustained reduction of PA diastolic pressure from baseline 24.7 mmHg to 21.0 at 1 year and 20.8 at 2 years for all patients. Patients completing two year follow-up (n = 710) showed similar 2-year reduction (23.9 to 20.8 mmHg), with reduction in PA mean pressure (33.7 to 29.4 mmHg) in patients with reduced left ventricular ejection. The HFH rate was 1.25 events/patient/year prior to sensor implant, 0.54 at 1 year, and 0.37 at 2 years, with 59% of patients free of HFH during follow-up. CONCLUSIONS: Reduction in PA pressures and hospitalizations were early and sustained during 2 years of PA pressure-guided management, with no signal of safety concerns regarding the implanted sensor.


Assuntos
Insuficiência Cardíaca , Monitorização Hemodinâmica , Humanos , Estados Unidos , Artéria Pulmonar , Monitorização Ambulatorial , Hospitalização , Monitorização Ambulatorial da Pressão Arterial/métodos
3.
Poult Sci ; 100(4): 101020, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33662658

RESUMO

Significant improvements in genetics, nutrition, and food efficiency have had a great impact on the rapid growth of broilers, notably with increases in muscle mass. However, with rapid growth, the broiler industry has been negatively impacted by the increased incidence of myopathies, including white striping. White striping affects the pectoralis major muscle of broilers, particularly the larger breasts of rapidly growing modern commercial broiler lines. In this study, we documented the growth process of commercial broiler chickens from hatching to market weight at 6 wk. Gross pathology and histopathology analyses were performed on pectoralis major muscle collected weekly from birds culled from 1 to 6 wk. The severity of both gross and histologic pathologies in the breast muscle increased over time. White striping was initially observed at week 2, with a rise in the incidence and severity through the sixth week. Mild histopathology was noted in week 2, characterized by macrophage infiltration and limited phagocytosis of the muscle. Muscle condition deteriorated with age and weight gain, with more prevalent macrophages, phagocytosis, and interstitial fibroblasts. By week 5 and 6, there was severe myopathy including regions of obliterated muscle tissue. Linear regression models show a positive correlation between white striping, gross pathology, and histopathology relative to weight and age.


Assuntos
Doenças Musculares , Doenças das Aves Domésticas , Animais , Galinhas , Incidência , Carne/análise , Doenças Musculares/epidemiologia , Doenças Musculares/etiologia , Doenças Musculares/veterinária , Músculos Peitorais , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/etiologia , Aumento de Peso
4.
BMC Res Notes ; 13(1): 459, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32993781

RESUMO

OBJECTIVE: Prophylactic supplementation of psyllium husk is recommended to enhance passage of ingested sand from the gastrointestinal tracts of horses. We hypothesized that psyllium supplementation would increase fecal sand passage and favorably alter bacterial populations in the hindgut. Six yearlings and six mature mares were fed a psyllium supplement in the diet daily for seven days. Voluntarily-voided feces were collected over the course of 29 days, prior, during, and after treatment. Feces were analyzed for acid detergent fiber (ADF) and acid detergent insoluble ash analyses. Microbial DNA was also isolated, and the V4 region of the 16S ribosomal RNA gene was PCR-amplified and sequenced using MiSeq technology. RESULTS: Fecal ADF concentration was greater in adults while silica concentration was greater in yearlings. Mature mare fecal ADF decreased during and just after supplementation but thereafter increased. No changes in silica levels were noted in either group over time. Fecal microbial population phylogenetic diversity was greatest mid-supplementation and lowest at 11 days post-supplementation. Functional profiles of the microbial communities presented some benefits for psyllium supplementation. These findings provide compelling evidence for further detailed studies of prophylactic psyllium supplementation.


Assuntos
Microbiota , Psyllium , Animais , Suplementos Nutricionais , Fezes , Feminino , Cavalos , Filogenia
5.
Circ Heart Fail ; 13(8): e006863, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32757642

RESUMO

BACKGROUND: Ambulatory hemodynamic monitoring with an implantable pulmonary artery (PA) sensor is approved for patients with New York Heart Association Class III heart failure (HF) and a prior HF hospitalization (HFH) within 12 months. The objective of this study was to assess the efficacy and safety of PA pressure-guided therapy in routine clinical practice with special focus on subgroups defined by sex, race, and ejection fraction. METHODS: This multi-center, prospective, open-label, observational, single-arm trial of 1200 patients across 104 centers within the United States with New York Heart Association class III HF and a prior HFH within 12 months evaluated patients undergoing PA pressure sensor implantation between September 1, 2014, and October 11, 2017. The primary efficacy outcome was the difference between rates of adjudicated HFH 1 year after compared with the 1 year before sensor implantation. Safety end points were freedom from device- or system-related complications at 2 years and freedom from pressure sensor failure at 2 years. RESULTS: Mean age for the population was 69 years, 37.7% were women, 17.2% were non-White, and 46.8% had preserved ejection fraction. During the year after sensor implantation, the mean rate of daily pressure transmission was 76±24% and PA pressures declined significantly. The rate of HFH was significantly lower at 1 year compared with the year before implantation (0.54 versus 1.25 events/patient-years, hazard ratio 0.43 [95% CI, 0.39-0.47], P<0.0001). The rate of all-cause hospitalization was also lower following sensor implantation (1.67 versus 2.28 events/patient-years, hazard ratio 0.73 [95% CI, 0.68-0.78], P<0.0001). Results were consistent across subgroups defined by ejection fraction, sex, race, cause of cardiomyopathy, presence/absence of implantable cardiac defibrillator or cardiac resynchronization therapy and ejection fraction. Freedom from device- or system-related complications was 99.6%, and freedom from pressure sensor failure was 99.9% at 1 year. CONCLUSIONS: In routine clinical practice as in clinical trials, PA pressure-guided therapy for HF was associated with lower PA pressures, lower rates of HFH and all-cause hospitalization, and low rates of adverse events across a broad range of patients with symptomatic HF and prior HFH. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02279888.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Insuficiência Cardíaca/terapia , Hospitalização/estatística & dados numéricos , Pressão Propulsora Pulmonar/fisiologia , Idoso , Feminino , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica , Humanos , Masculino , Estudos Prospectivos , Artéria Pulmonar , Estados Unidos/epidemiologia
6.
PLoS One ; 14(4): e0216211, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31039168

RESUMO

A healthy gastrointestinal (GI) tract with a properly established microbiota is necessary for a foal to develop into a healthy weanling. A foal's health can be critically impacted by aberrations in the microbiome such as with diarrhea which can cause great morbidity and mortality in foals. In this study, we hypothesized that gut establishment in the foal transitioning from a diet of milk to a diet of grain, forage, and pasture would be detectable through analyses of the fecal microbiotas. Fecal samples from 37 sets of foals and mares were collected at multiple time points ranging from birth to weaning. Bacterial DNA was isolated from the samples, and the V4 domain of bacterial 16S rRNA genes were amplified via polymerase chain reaction. Next generation sequencing was then performed on the resulting amplicons, and analyses were performed to characterize the microbiome as well as the relative abundance of microbiota present. We found that bacterial population compositions followed a pattern throughout the early life of the foal in an age-dependent manner. As foals transitioned from milk consumption to a forage and grain diet, there were recognizable changes in fecal microbial compositions from initial populations predominant in the ability to metabolize milk to populations capable of utilizing fibrous plant material. We were also able to recognize differences in microbial populations amongst diarrheic foals as well as microbial population differences associated with differences in management styles between facilities. Future efforts will gauge the effects of lesser abundant bacterial populations that could also be essential to GI health, as well as to determine how associations between microbial population profiles and animal management practices can be used to inform strategies for improving upon the health and growth of horses overall.


Assuntos
Fezes/microbiologia , Trato Gastrointestinal/microbiologia , Cavalos/microbiologia , Microbiota , Desmame , Animais , Animais Recém-Nascidos , Bactérias/crescimento & desenvolvimento , Biodiversidade , Metagenômica , Filogenia , Análise de Componente Principal
7.
Poult Sci ; 98(1): 413-421, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30690615

RESUMO

Conventional broiler diets include synthetic methionine to optimize fast muscle growth. Recently, a conventional synthetic methionine-rich diet was compared to alternative diet regimens providing natural sources of methionine. Broilers fed diets with natural methionine sources grew at a slightly slower rate. From this study, we hypothesized that the difference in a growth rate would be reflected in features of the breast muscle from broilers fed the alternative diet. We hypothesized that white striping of pectoralis major muscle would be reduced in slower growing broilers fed the alternative diet regimen with natural methionine. We also hypothesized that there would be associated differences in gene expression for cell differentiation and pathology markers. Broilers fed a conventional corn/soy diet regimen with synthetic methionine were compared to those fed roasted cowpea and sunflower seed meal (60% corn/soy, 20% sunflower seed meal, and 20% roasted cowpea) and no synthetic methionine. Overall broiler growth, muscle gene expression, and muscle collagen content data were compared. Expression analyses of combinations of MYOD1, PPARG, COL1A2, TRIM63, SOD1, PTGS2, and CD36 genes were used to examine differentiation and inflammation in the pectoralis muscles. The group fed an alternative diet gained less weight than those fed the control diet in the starter and grower phases but not in the finisher phase. Ultimately, the conventional diet resulted in a greater final weight for the broilers. However, mean white striping scores for the pectoralis major muscles were greater in the conventional control diet regimen. Gene expression results indicated greater expression of PPARG, PTGS2, and CD36 in the muscle of broilers fed the control diet. These data associate white striping with fat deposition and inflammation. Thus, whether due to differences in feed intake, growth rate, or actual compositional differences, the alternative diet with natural methionine sources seemed to curtail amounts of white striping in broiler muscle. More studies are necessary to further discern the effect of growth rate and natural methionine sources on white striping.


Assuntos
Ração Animal/análise , Galinhas , Metionina/administração & dosagem , Doenças Musculares/veterinária , Doenças das Aves Domésticas/metabolismo , Animais , Dieta/veterinária , Feminino , Expressão Gênica , Masculino , Carne/análise , Metionina/efeitos adversos , Doenças Musculares/genética , Doenças Musculares/metabolismo , Músculos Peitorais/química , Músculos Peitorais/crescimento & desenvolvimento , Doenças das Aves Domésticas/genética
8.
Environ Toxicol Chem ; 36(5): 1294-1300, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27764895

RESUMO

The authors quantified hepatic hydrocarbon-inducible cytochrome P4501A (CYP1A) expression, as ethoxyresorufin-O-deethylase (EROD) activity, in wintering harlequin ducks (Histrionicus histrionicus) captured in Prince William Sound, Alaska (USA), during 2011, 2013, and 2014 (22-25 yr following the 1989 Exxon Valdez oil spill). Average EROD activity was compared between birds from areas oiled by the spill and those from nearby unoiled areas. The present study replicated studies conducted from 1998 to 2009 demonstrating that harlequin ducks using areas oiled in 1989 had elevated EROD activity, indicative of oil exposure, up to 2 decades post spill. In the present study, it was found that average EROD activity during March 2011 was significantly higher in wintering harlequin ducks captured in oiled areas relative to unoiled areas, which the authors interpret to indicate that harlequin ducks continued to be exposed to residual Exxon Valdez oil up to 22 yr after the original spill. However, the 2011 results also indicated reductions in exposure relative to previous years. Average EROD activity in birds from oiled areas was approximately 2 times that in birds from unoiled areas in 2011, compared with observations from 2005 to 2009, in which EROD activity was 3 to 5 times higher in oiled areas. It was also found that average EROD activity during March 2013 and March 2014 was not elevated in wintering harlequin ducks from oiled areas. The authors interpret these findings to indicate that exposure of harlequin ducks to residual Exxon Valdez oil abated within 24 yr after the original spill. The present study finalizes a timeline of exposure, extending over 2 decades, for a bird species thought to be particularly vulnerable to oil contamination in marine environments. Environ Toxicol Chem 2017;36:1294-1300. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.


Assuntos
Biomarcadores/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Patos/metabolismo , Poluição por Petróleo , Animais , Monitoramento Ambiental , Hidrocarbonetos/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo
9.
J Biochem Mol Toxicol ; 26(12): 506-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23169765

RESUMO

The carbamate pyridostigmine bromide has been used as a pretreatment to protect individuals from the nerve agent soman. Previous research showed that pyridostigmine significantly protected human muscle acetylcholinesterase in vitro from soman and bovine red blood cell acetylcholinesterase from some organophosphorous pesticides. Research presented here demonstrates that pretreatment with other carbamates also protects acetylcholinesterase from inhibition by the pesticides chlorpyrifos-oxon and diazinon-oxon, but not from malaoxon.


Assuntos
Carbamatos/farmacologia , Inibidores da Colinesterase/toxicidade , Organofosfatos/toxicidade , Praguicidas/toxicidade , Animais , Bovinos , Clorpirifos/análogos & derivados , Clorpirifos/toxicidade , Compostos Organofosforados/toxicidade
10.
Environ Toxicol Chem ; 31(12): 2828-31, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22933448

RESUMO

We evaluated chronic exposure of harlequin ducks (Histrionicus histrionicus) to hydrocarbons associated with the 2004 M/V Selendang Ayu oil spill at Unalaska Island, Alaska. We measured levels of hepatic 7-ethoxyresorufin-O-deethylase activity (EROD) in liver biopsy samples as an indicator of hydrocarbon exposure in three oiled bays and one reference bay in 2005, 2006, and 2008. Median EROD activity in ducks from oiled bays was significantly higher than in the reference bay in seven of nine pairwise comparisons. These results indicated that harlequin ducks were exposed to lingering hydrocarbons more than three years after the spill.


Assuntos
Patos/metabolismo , Hidrocarbonetos/metabolismo , Poluição por Petróleo , Poluentes Químicos da Água/metabolismo , Alaska , Animais , Citocromo P-450 CYP1A1/metabolismo , Monitoramento Ambiental , Feminino , Hidrocarbonetos/análise , Fígado/metabolismo , Masculino , Poluentes Químicos da Água/análise
11.
J Biochem Mol Toxicol ; 26(1): 31-4, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21972196

RESUMO

Pyridostigmine bromide (PB) has been used to protect soldiers from the toxic effects of soman, a chemical warfare agent. Recent research shows that pyridostigmine bromide protects a significant percentage of acetylcholinesterase in isolated human intercostal muscle. Findings presented here indicate that red blood cell acetylcholinesterase is similarly protected by pyridostigmine bromide from the action of diisopropyl fluorophosphate and several organophosphate pesticides including chlorpyrifos-oxon, diazinon-oxon, and paraoxon, but not malaoxon, using the bovine red blood cell as a subject. These findings suggest that pretreatment with PB may protect growers, farmworkers, first responders, and the public, in general, from the effects of selected pesticides.


Assuntos
Clorpirifos/análogos & derivados , Inibidores da Colinesterase/toxicidade , Malation/análogos & derivados , Compostos Organofosforados/toxicidade , Paraoxon/toxicidade , Praguicidas/toxicidade , Substâncias Protetoras/farmacologia , Brometo de Piridostigmina/farmacologia , Acetilcolinesterase/metabolismo , Animais , Bovinos , Clorpirifos/toxicidade , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Malation/toxicidade
12.
Muscle Nerve ; 43(4): 591-5, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21404290

RESUMO

INTRODUCTION: Pretreatment with pyridostigmine bromide (PB) of human intercostal muscle fibers exposed to the irreversible acetylcholinesterase (AChE) inhibitor soman was investigated. METHODS: Muscles were pretreated with 3 × 10(-6) M PB or saline for 20 minutes, then exposed to 10(-7) M soman for 10 minutes. RESULTS: AChE of muscles treated with soman alone was inhibited >95%. In contrast, PB pretreatment of soman-exposed bundles protected 20% of AChE activity. AChE of bundles exposed to PB alone recovered after 4 hours, but bundles exposed to both PB and soman did not. Soman-induced reduction of resting membrane potentials and increment of amplitudes and decay times of miniature endplate potentials (MEPPs) were partially corrected by PB pretreatment. CONCLUSIONS: In vitro pretreatment of human muscles with PB protected up to 20% of muscle AChE and ameliorated some deleterious effects on endplate physiology induced by soman.


Assuntos
Acetilcolinesterase , Inibidores da Colinesterase/farmacologia , Músculos Intercostais/efeitos dos fármacos , Músculos Intercostais/enzimologia , Brometo de Piridostigmina/farmacologia , Soman/toxicidade , Acetilcolinesterase/metabolismo , Relação Dose-Resposta a Droga , Humanos , Técnicas de Cultura de Órgãos , Substâncias Protetoras/farmacologia
13.
Mar Pollut Bull ; 62(3): 609-14, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21131011

RESUMO

We examined hepatic EROD activity, as an indicator of CYP1A induction, in Barrow's goldeneyes captured in areas oiled during the 1989 Exxon Valdez spill and those from nearby unoiled areas. We found that average EROD activity differed between areas during 2005, although the magnitude of the difference was reduced relative to a previous study from 1996/1997, and we found that areas did not differ by 2009. Similarly, we found that the proportion of individuals captured from oiled areas with elevated EROD activity (≥ 2 times unoiled average) declined from 41% in winter 1996/1997 to 10% in 2005 and 15% in 2009. This work adds to a body of literature describing the timelines over which vertebrates were exposed to residual Exxon Valdez oil and indicates that, for Barrow's goldeneyes in Prince William Sound, exposure persisted for many years with evidence of substantially reduced exposure by 2 decades after the spill.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Patos/metabolismo , Exposição Ambiental/análise , Petróleo/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Biomarcadores/metabolismo , Vazamento de Resíduos Químicos , Feminino , Fígado/metabolismo , Masculino , Petróleo/toxicidade , Poluentes Químicos da Água/toxicidade
14.
Environ Toxicol Chem ; 29(5): 1138-45, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20821550

RESUMO

Hydrocarbon-inducible cytochrome P4501A (CYP1A) expression was measured, as ethoxyresorufin-O-deethylase (EROD) activity, in livers of wintering harlequin ducks (Histrionicus histrionicus) captured in areas of Prince William Sound, Alaska, USA, oiled by the 1989 Exxon Valdez spill and in birds from nearby unoiled areas, during 2005 to 2009 (up to 20 years following the spill). The present work repeated studies conducted in 1998 that demonstrated that in harlequin ducks using areas that received Exxon Valdez oil, EROD activity was elevated nearly a decade after the spill. The present findings strongly supported the conclusion that average levels of hepatic EROD activity were higher in ducks from oiled areas than those from unoiled areas during 2005 to 2009. This result was consistent across four sampling periods; furthermore, results generated from two independent laboratories using paired liver samples from one of the sampling periods were similar. The EROD activity did not vary in relation to age, sex, or body mass of individuals, nor did it vary strongly by season in birds collected early and late in the winter of 2006 to 2007, indicating that these factors did not confound inferences about observed differences between oiled and unoiled areas. We interpret these results to indicate that harlequin ducks continued to be exposed to residual Exxon Valdez oil up to 20 years after the original spill. This adds to a growing body of literature suggesting that oil spills have the potential to affect wildlife for much longer time frames than previously assumed.


Assuntos
Biomarcadores , Citocromo P-450 CYP1A1/metabolismo , Patos , Petróleo/toxicidade , Poluentes Químicos da Água/toxicidade , Alaska , Animais , Exposição Ambiental , Indução Enzimática , Estações do Ano , Fatores de Tempo
15.
Drug Chem Toxicol ; 32(3): 182-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19538013

RESUMO

The normal range of human erythrocyte acetylcholinesterase (RBC-AChE) activity is important when monitoring exposure to pesticides and chemical warfare agents. A modification of Michel's method measured RBC-AChE activities from 991 individuals (818 males and 173 females) presumably unexposed to nerve agents. Median age was 42 (range, 18-76) years. RBC-AChE (mean +/- SD) was 0.74 +/- 0.06 delta pH units/hour. Multivariate linear regression showed an association with age (slope +0.0008 delta pH units/hour for each year; P < 0.001) unlikely to be clinically significant. The findings represent the largest study of human RBC-AChE to date providing measures of central tendency and variation.


Assuntos
Acetilcolinesterase/sangue , Eritrócitos/enzimologia , Adolescente , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
16.
Bull Environ Contam Toxicol ; 83(1): 59-61, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19387522

RESUMO

Court-ordered monitoring of blood cholinesterases (ChEs) from orchard workers in Washington State is underway. In 2008, the mean red blood cell acetylcholinesterase (AChE, EC 3.1.1.7) activity was 9.65 +/- 1.11 micromoles/min/ml (n = 1,793) and the mean serum (BChE, 3.1.1.6) activity was 5.19 +/- 0.90 micromoles/min/ml (n = 1,811). Determinations were made using the Ellman assay and automated equipment of Pathology Associates Medical Laboratories (PAML), Spokane, Washington.


Assuntos
Agricultura , Colinesterases/sangue , Exposição Ocupacional , Acetilcolinesterase/sangue , Eritrócitos/enzimologia , Humanos , Washington
17.
Curr Protoc Toxicol ; Chapter 12: Unit12.13, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23045138

RESUMO

The widespread use of organophosphate and organocarbamate pesticides and the dangers of related chemical warfare agents dramatize the importance of rapid, accurate, and sensitive assays for blood and tissue cholinesterases (ChEs), important targets for neurotoxic chemicals. Two ChE enzymes used as biomarkers of exposure are the specific acetylcholinesterases (AChE, EC 3.1.1.7) and the nonspecific plasma cholinesterases (BChE, EC 3.1.1.8). This unit contains two protocols for measuring ChE activity: (1) a colorimetric kinetic method and (2) a radiometric endpoint assay and selective inhibitors that are used to distinguish between the two classes of enzymes.


Assuntos
Acetilcolinesterase , Encéfalo , Butirilcolinesterase , Músculos , Acetilcolinesterase/sangue , Acetilcolinesterase/metabolismo , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/enzimologia , Butirilcolinesterase/sangue , Butirilcolinesterase/metabolismo , Substâncias para a Guerra Química/toxicidade , Inibidores da Colinesterase/farmacologia , Colorimetria , Exposição Ambiental/análise , Humanos , Músculos/diagnóstico por imagem , Músculos/enzimologia , Organofosfatos/toxicidade , Cintilografia , Contagem de Cintilação , Especificidade por Substrato , Trítio
18.
Chem Biol Interact ; 157-158: 253-6, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16298353

RESUMO

Progress toward a standard blood cholinesterase assay to assess pesticide exposures in the agricultural workplace and to identify possible victims of chemical warfare agents is discussed. Examples given are drawn from collaborations with clinical laboratories in California and the Department of Defense Cholinesterase Reference Laboratory (CRL).


Assuntos
Colinesterases/metabolismo , Praguicidas/análise , Praguicidas/farmacologia , Animais , Biomarcadores/sangue , California , Química Clínica/métodos , Química Clínica/normas , Colinesterases/sangue , Cães , Humanos , Masculino , Ratos
19.
Environ Toxicol Chem ; 24(8): 2074-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16152981

RESUMO

This investigation evaluated whether acetylcholinesterase (AChE) in Pacific tree frogs (Hyla regilla) from different geographical locations was influenced by different temperatures during early aquatic life stages, independent of pesticide exposure. Tadpoles were collected from both a California coastal pond and a Sierra Nevada mountain range pond, USA. Groups of frogs from each location were raised in temperatures representative of either the Sierra Nevada (8 degrees C) or the coastal (19 degrees C) location. Metamorphs from both locations raised as tadpoles at 19 degrees C had AChE activities of 42.3 and 38.7 nm/min/mg protein, while those raised as tadpoles at 8 degrees C had activities of 26.9 and 28.2 nm/min/mg protein. A two-way analysis of variance revealed temperature to be the significant factor in determining AChE activity (F = 22.3, p < 0.001), although origin was not important (F = 0.09, p = 0.75). Interpretations regarding the influence of pesticides upon AChE activity in Pacific tree frogs must consider the influence of environmental temperature to enable cross-population comparisons.


Assuntos
Acetilcolinesterase/metabolismo , Anfíbios , Temperatura , Água , Animais , Butirilcolinesterase/metabolismo
20.
Environ Toxicol Chem ; 23(11): 2719-26, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15559288

RESUMO

Organophosphorous (OP) insecticides, especially diazinon, have been detected routinely in surface waters of the Sacramento and San Joaquin River watersheds, coincident with rainfall events following their application to dormant orchards during the winter months. Preventive best management practices (BMP) aim at reducing off-site movement of pesticides into surface waters. Two proposed BMPs are: The use of more hydrophobic pyrethroid insecticides believed to adsorb strongly to organic matter and soil and the use of various types of ground cover vegetation to increase the soil's capacity for water infiltration. To measure the effectiveness of these BMPs, storm water runoff was collected in a California prune orchard (Glenn County, CA, USA) during several rainstorms in the winter of 2001, after the organophosphate diazinon and the pyrethroid esfenvalerate were applied to different orchard sections. We tested and compared acute toxicity of orchard runoff from diazinon- and esfenvalerate-sprayed sections to two species of fish (Pimephales promelas, Onchorhynchus mykiss) and three aquatic invertebrates (Ceriodaphnia dubia, Simocephalus vetelus, Chironomus riparius), and determined the mitigating effect of three ground cover crops on toxicity and insecticide loading in diazinon-sprayed orchard rows. Runoff from the esfenvalerate-sprayed orchard section was less toxic to waterflea than runoff from the diazinon-sprayed section. However, runoff from the orchard section sprayed with esfenvalerate was highly toxic to fish larvae. Samples collected from both sections one month later were not toxic to fish, but remained highly toxic to invertebrates. The ground cover crops reduced total pesticide loading in runoff by approximately 50%. No differences were found between the types of vegetation used as ground covers.


Assuntos
Diazinon/toxicidade , Inseticidas/toxicidade , Piretrinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , California , Chironomidae/efeitos dos fármacos , Cladocera/efeitos dos fármacos , Cyprinidae , Inseticidas/análise , Larva/efeitos dos fármacos , Medicago , Nitrilas , Nível de Efeito Adverso não Observado , Oncorhynchus mykiss , Poaceae , Chuva/química , Rios/química , Estações do Ano , Poluentes Químicos da Água/análise
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