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1.
Pestic Biochem Physiol ; 189: 105296, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36549822

RESUMO

Microtransplantation of neurolemma tissue fragments from mammalian brain into the plasma membrane of Xenopus laevis oocytes is a tool to examine the endogenous structure and function of various ion channels and receptors associated with the central nervous system. Microtransplanted neurolemma can originate from a variety of sources, contain ion channels and receptors in their native configuration, and are applicable to examine diseases associated with different channelopathies. Here, we examined potential age-related differences in voltage-sensitive sodium channel (VSSC) expression and concentration-dependent responses to pyrethroids following the microtransplantation of juvenile or adult rat brain tissue (neurolemma) into X. laevis oocytes. Using automated western blotting, adult neurolemma exhibited a 2.5-fold higher level of expression of VSSCs compared with juvenile neurolemma. The predominant isoform expressed in both tissues was Nav1.2. However, adult neurolemma expressed 2.8-fold more Nav1.2 than juvenile and expressed Nav1.6 at a significantly higher level (2.2-fold). Microtransplanted neurolemma elicited ion currents across the plasma membrane of oocytes following membrane depolarization using two electrode voltage clamp electrophysiology. A portion of this current was sensitive to tetrodotoxin (TTX) and this TTX-sensitive current was abolished when external sodium ion was replaced by choline ion, functionally demonstrating the presence of native VSSC. Increasing concentrations of permethrin or deltamethrin exhibited concentration-dependent increases in inward TTX-sensitive current in the presence of niflumic acid from both adult and juvenile tissues following a pulsed depolarization of the oocyte plasma membrane. Concentration-dependent response curves illustrate that VSSCs associated with juvenile neurolemma were up to 2.5-fold more sensitive to deltamethrin than VSSCs in adult neurolemma. In contrast, VSSCs from juvenile neurolemma were less sensitive to permethrin than adult VSSCs at lower concentrations (0.6-0.8-fold) but were more sensitive at higher concentrations (up to 2.4-fold). Nonetheless, because the expected concentrations in human brains following realistic exposure levels are approximately 21- (deltamethrin) to 333- (permethrin) times below the threshold concentration for response in rat neurolemma-injected oocytes, age-related differences, if any, are not likely to be toxicologically relevant.


Assuntos
Inseticidas , Piretrinas , Ratos , Animais , Humanos , Inseticidas/toxicidade , Inseticidas/química , Permetrina/toxicidade , Canais de Sódio/metabolismo , Piretrinas/toxicidade , Piretrinas/química , Canais Iônicos/metabolismo , Oócitos/metabolismo , Encéfalo/metabolismo , Xenopus laevis/metabolismo , Mamíferos/metabolismo
2.
Pestic Biochem Physiol ; 181: 105013, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35082036

RESUMO

Pediculus lice represent one of the longest and most prevalent parasitic infestations of humans. Head lice are an economic and social concern whereas body lice pose a more serious public health threat. Significant progress has been made in the study of human lice over the last 10 years, allowing for new approaches in their control. An in vitro rearing system has made it possible to maintain insecticide-susceptible and -resistant reference strains, which allowed an in depth study of pediculicide resistance, including its underlying molecular mechanisms and the detection and monitoring of resistance. The generation of inbreed strains facilitated the efficient sequencing, assembly and annotation of the genomes and transcriptomes of both lice. The use of functional genomics and reverse genetics elucidated the genetics involved in the evolution of resistance and the discovery of novel target sites for the development of new pediculicides. In this review, four new effective pediculicide products, each with different mode of action and unique chemistries, will be presented. They have been found to be safe and selective, and control resistant lice. As such, they meet the criteria necessary to be used in rotations as a sustainable resistance management strategy.


Assuntos
Inseticidas , Infestações por Piolhos , Pediculus , Animais , Humanos , Inseticidas/farmacologia , Infestações por Piolhos/prevenção & controle , Pediculus/genética
3.
Pestic Biochem Physiol ; 184: 105114, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715053

RESUMO

Previously, deltamethrin (a Type-II pyrethroid) has been reported to increase triglyceride (fat) accumulation in adipocytes, while its underlying molecular mechanism is not fully determined. The aim of this study was to further investigate the molecular mechanisms of deltamethrin induced fat accumulation in murine 3T3-L1 adipocytes. Consistent to previous reports, deltamethrin (10 µM) significantly promoted adipogenesis in 3T3-L1 adipocytes. RNA sequencing (RNA-seq) results showed that 721 differentially expressed genes (DEGs) were identified after deltamethrin treatment, involving in 58 Functional groups of Gene Ontology (GO) and 255 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Several key functional groups regulating adipogenesis, such as fat cell differentiation (Igf1, Snai2, Fgf10, and Enpp1) and cytosolic calcium ion concentration (Nos1, Cxcl1, and Ngf) were significantly enriched. Collectively, these results suggest that the promotion of adipogenesis by deltamethrin was attributed to an obesogenic global transcriptomic response, which provides further understanding of the underlying mechanisms of deltamethrin-induced fat accumulation.


Assuntos
Adipócitos , Piretrinas , Células 3T3-L1 , Adipogenia/genética , Animais , Perfilação da Expressão Gênica , Camundongos , Nitrilas , Piretrinas/metabolismo , Piretrinas/toxicidade
4.
Cardiol Young ; 32(10): 1580-1584, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34789361

RESUMO

BACKGROUND: Patients with CHD can be exposed to high levels of cumulative ionising radiation. Utilisation of electroanatomic mapping during catheter ablation leads to reduced radiation exposure in the general population but has not been well studied in patients with CHD. This study evaluated the radiation sparing benefit of using three-dimensional mapping in patients with CHD. METHODS: Data were retrospectively collected from the Catheter Ablation with Reduction or Elimination of Fluoroscopy multi-institutional registry. Patients with CHD were selected. Those with previous ablations, concurrent diagnostic or interventional catheterisation and unknown arrhythmogenic foci were excluded. The control cohort was matched for operating physician, arrhythmia mechanism, arrhythmia location, weight and age. The procedure time, rate of fluoroscopy use, fluoroscopy time, procedural success, complications, and distribution of procedures per year were compared between the two groups. RESULTS: Fifty-six patients with congenital heart disease and 56 matched patients without CHD were included. The mean total procedure time was significantly higher in patients with CHD (212.6 versus 169.5 minutes, p = 0.003). Their median total fluoroscopy time was 4.4 minutes (compared to 1.8 minutes), and their rate of fluoroscopy use was 23% (compared to 13%). The acute success and minor complication rates were similar and no major complications occurred. CONCLUSIONS: With the use of electroanatomic mapping during catheter ablation, fluoroscopy use can be reduced in patients with CHD. The majority of patients with CHD received zero fluoroscopy.


Assuntos
Ablação por Cateter , Exposição à Radiação , Humanos , Mapeamento Potencial de Superfície Corporal/métodos , Estudos Retrospectivos , Resultado do Tratamento , Exposição à Radiação/prevenção & controle , Fluoroscopia/métodos , Ablação por Cateter/métodos , Arritmias Cardíacas/epidemiologia
5.
Pestic Biochem Physiol ; 171: 104727, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357549

RESUMO

Insecticide resistance is an ongoing challenge in agriculture and disease vector control. Here, we demonstrate a novel strategy to attenuate resistance. We used genomics tools to target fundamental energy-associated pathways and identified a potential "Achilles' heel" for resistance, a resistance-associated protein that, upon inhibition, results in a substantial loss in the resistance phenotype. Specifically, we compared the gene expression profiles and structural variations of the insulin/insulin-like growth factor signaling (IIS) pathway genes in DDT-susceptible (91-C) and -resistant (91-R) Drosophila melanogaster (Drosophila) strains. A total of eight and seven IIS transcripts were up- and down-regulated, respectively, in 91-R compared to 91-C. A total of 114 nonsynonymous mutations were observed between 91-C and 91-R, of which 51.8% were fixed. Among the differentially expressed transcripts, phosphoenolpyruvate carboxykinase (PEPCK), down-regulated in 91-R, encoded the greatest number of amino acid changes, prompting us to perform PEPCK inhibitor-pesticide exposure bioassays. The inhibitor of PEPCK, hydrazine sulfate, resulted in a 161- to 218-fold decrease in the DDT resistance phenotype (91-R) and more than a 4- to 5-fold increase in susceptibility in 91-C. A second target protein, Glycogen synthase kinase 3ß (GSK3ß-PO), had one amino acid difference between 91-C and 91-R, and the corresponding transcript was also down-regulated in 91-R. A GSK3ß-PO inhibitor, lithium chloride, likewise reduced the resistance but to a lesser extent than did hydrazine sulfate for PEPCK. We demonstrate the potential role of IIS genes in DDT resistance and the potential discovery of an "Achilles' heel" against pesticide resistance in this pathway.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Animais , DDT/farmacologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Calcanhar , Resistência a Inseticidas/genética , Insulina , Transdução de Sinais
6.
Cardiol Young ; 31(12): 1923-1928, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33766172

RESUMO

BACKGROUND: Catheter ablation is a safe and effective therapy for the treatment of supraventricular tachycardia in children. Current improvements in technology have allowed progressive reduction in radiation exposure associated with the procedure. To assess the impact of three-dimensional mapping, we compared acute procedural results collected from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry to published results from the Prospective Assessment after Pediatric Cardiac Ablation study. METHODS: Inclusion and exclusion criteria from the Prospective Assessment after Pediatric Cardiac Ablation study were used as guidelines to select patient data from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry to compare acute procedural outcomes between cohorts. Outcomes assessed include procedural and fluoroscopy exposure times, success rates of procedure, and complications. RESULTS: In 786 ablation procedures, targeting 498 accessory pathways and 288 atrioventricular nodal reentrant tachycardia substrates, average procedural time (156.5 versus 206.7 minutes, p < 0.01), and fluoroscopy time (1.2 versus 38.3 minutes, p < 0.01) were significantly shorter in the study group. Success rates for the various substrates were similar except for manifest accessory pathways which had a significantly higher success rate in the study group (96.4% versus 93.0%, p < 0.01). Major complication rates were significantly lower in the study group (0.3% versus 1.6%, p < 0.01). CONCLUSIONS: In a large, multicentre study, three-dimensional systems show favourable improvements in clinical outcomes in children undergoing catheter ablation of supraventricular tachycardia compared to the traditional fluoroscopic approach. Further improvements are anticipated as technology advances.


Assuntos
Ablação por Cateter , Taquicardia Supraventricular , Criança , Fluoroscopia , Humanos , Estudos Prospectivos , Taquicardia Supraventricular/cirurgia , Resultado do Tratamento
7.
Pestic Biochem Physiol ; 168: 104631, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32711765

RESUMO

Herbivorous insects encounter a variety of toxic environmental substances ranging from ingested plant defensive compounds to human-introduced insecticidal agents. Dietary antioxidants are known to reduce the negative physiological impacts of toxins in mammalian systems through amelioration of reactive oxygen-related cellular damage. The analogous impacts to insects caused by multigenerational exposure to pesticides and the effects on adaptive responses within insect populations, however, are currently unknown. To address these research gaps, we used Drosophila as a model system to explore adaptive phenotypic responses to acute dichlorodiphenyltrichloroethane (DDT) exposure in the presence of the dietary antioxidant vitamin C and to examine the structural genomic consequences of this exposure. DDT resistance increased significantly among four replicates exposed to a low concentration of DDT for 10 generations. In contrast, dietary intake of vitamin C significantly reduced DDT resistance after mutigenerational exposure to the same concentration of DDT. As to the genomic consequences, no significant differences were predicted in overall nucleotide substitution rates across the genome between any of the treatments. Despite this, replicates exposed to a low concentration of DDT without vitamin C showed the highest number of synonymous and non-synonymous variants (3196 in total), followed by the DDT plus vitamin C (1174 in total), and vitamin C alone (728 in total) treatments. This study demonstrates the potential role of diet (specifically, antioxidant intake) on adaptive genome responses, and thus on the evolution of pesticide resistance within insect populations.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Inseticidas/farmacologia , Animais , Antioxidantes , Ácido Ascórbico , DDT , Dieta , Humanos , Resistência a Inseticidas/efeitos dos fármacos
8.
Anal Chem ; 91(3): 2093-2099, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30628431

RESUMO

Understanding the behavior of pesticide translocation is significant for effectively applying pesticides and reducing pesticide exposures from treated plants. Herein, we applied surface enhanced Raman spectroscopy (SERS) for real-time monitoring of pesticide translocation in tomato plant tissues, including leaves and flowers, following root exposure in hydroponic and soil systems. Various concentrations of the systemic pesticide, thiabendazole, was introduced into hydroponic systems used for growing tomato plants. At selected time intervals, tomato leaves and flowers were picked and thiabendazole was measured directly under a Raman microscope after pipetting gold nanoparticle-containing solution onto the plant tissue. We found that the pesticide signals first appeared along the midrib in the lowest leaves and moved distally to the edge of the leaves. As the concentration of pesticide applied to the root was increased, the time necessary to detect the signal was decreased. The SERS surface mapping method was also able to detect thiabendazole in the trichomes of the leaves. In addition, we found a unique SERS peak at 737 cm-1 on both leaves and flowers at 4 and 6 days following the application of 200 mg/L thiabendazole to the hydroponic system. This peak appears to be coming from adenine-containing materials and may be related to the plant's response to pesticide toxicity, which could be used as a potential marker for monitoring plant responses to stresses. These results demonstrate a successful application of SERS as a rapid and effective way to study the real-time translocation behavior of pesticides in a plant system.


Assuntos
Praguicidas/análise , Solanum lycopersicum/química , Tiabendazol/análise , Solanum lycopersicum/metabolismo , Praguicidas/farmacocinética , Análise Espectral Raman , Tiabendazol/farmacocinética , Fatores de Tempo
9.
Pestic Biochem Physiol ; 161: 86-94, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31685201

RESUMO

While insecticide resistance presents a challenge for those intent on controlling insect populations, these challenges have also generated a set of tools that can be used to ask fundamental biological questions about that resistance. Numerous species of insects have evolved resistance to multiple classes of insecticides. Each one of these species and their respective resistant populations represent a potential tool for understanding the molecular basis of the evolution of resistance. However, in-laboratory maintenance of resistant insect populations (and their comparative susceptible populations) suitable for asking the needed set of questions around the molecular consequences of long-term pesticide exposure requires a significant, in places prohibitive, level of resources. Drosophila melanogaster (hereafter referred to as Drosophila) is a model insect system with populations easily selected with pesticides and readily maintainable over decades. Even within Drosophila, however, few populations exist where long-term pesticide selection has occurred along with contrasting non-selected population. As such, the Drosophila 91-C and 91-R populations, which exhibit insecticide resistance to DDT (91-R), compared to a non-selection population (91-C), represent a unique resource for the study of high level DDT resistance. Moreover, with the availability of "omics" technologies over the past several decades, this paired population has emerged as a useful tool for understanding both the molecular basis of pesticide resistance and the molecular consequences of long-term pesticide exposure. In this review, we summarize the studies with these aforementioned populations over the past several decades, addressing what has been learned from these efforts.


Assuntos
DDT/farmacologia , Drosophila melanogaster/efeitos dos fármacos , Resistência a Inseticidas/genética , Animais , Drosophila melanogaster/genética , Genoma de Inseto , Inativação Metabólica/genética
10.
Int J Food Sci Nutr ; 70(8): 959-969, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31010351

RESUMO

There is increasing interest in the potential role of epigallocatechin gallate (EGCG) in changing body composition to lower body fat with increased lean mass. In this study, we examined the sex-dependent effect of EGCG on body composition, locomotion, feeding behaviour, sugar levels, and transcription levels of key regulators in lipid, carbohydrate, and energy metabolisms in Drosophila melanogaster. EGCG had no effects on body weights in both females and males, but decreased fat accumulation in females compared to the control, accompanied by a reduction in food intake. EGCG treatments increased lean mass and locomotor activity, and downregulated transcription levels of brummer (bmm), adipokinetic hormone (akh), and Drosophila insulin-like peptide 2 (dilp2), and upregulated spargel (srl) in males. In addition, EGCG decreased sugar levels in both females and males. In conclusion, EGCG promotes lean phenotype in D. melanogaster via sex-specific metabolic regulations.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Catequina/análogos & derivados , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/metabolismo , Animais , Antioxidantes/farmacologia , Composição Corporal/efeitos dos fármacos , Peso Corporal , Catequina/farmacologia , Regulação para Baixo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Metabolismo Energético , Feminino , Homeostase , Hormônios de Inseto/genética , Hormônios de Inseto/metabolismo , Lipase/genética , Lipase/metabolismo , Masculino , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Oligopeptídeos/genética , Oligopeptídeos/metabolismo , Fator B de Elongação Transcricional Positiva/genética , Fator B de Elongação Transcricional Positiva/metabolismo , Ácido Pirrolidonocarboxílico/análogos & derivados , Ácido Pirrolidonocarboxílico/metabolismo , Fatores Sexuais
11.
Pestic Biochem Physiol ; 196: 105582, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37945219
12.
Pediatr Emerg Care ; 34(1): 38-41, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27261956

RESUMO

OBJECTIVE: Ondansetron improves the success of oral rehydration in children with gastroenteritis. In postoperative adults, ondansetron has been shown to prolong the corrected QT (QTc). The aim of the study was to evaluate the effect of ondansetron on the QT at peak effect and at 1-hour postpeak effect in pediatric patients. METHODS: This was an observational study looking at patients aged 6 months to 18 years receiving intravenous ondansetron for nausea, vomiting, or the inability to take fluids in the emergency department. Patients had electrocardiogram performed at baseline, at ondansetron's peak effect, and 1 hour postpeak effect. A paired samples Student t test compared QTc change at peak effect to zero. Peak effect of intravenous ondansetron is 3 minutes. RESULTS: One hundred patients were included. Fifty-five percent of patients were female with a mean age of 8.3 years. The mean (range) baseline QTc was 435 (388 to 501) milliseconds. The mean (range) change in QTc at peak effect of ondansetron was 3 (-40 to 65) milliseconds (P = 0.072). The change in QTc 1-hour postpeak effect of ondansetron was 3 (-43 to 45) milliseconds (P = 0.082). No change at peak effect or 1-hour postpeak effect was clinically significant. CONCLUSIONS: Ondansetron does not affect the QTc of pediatric patients receiving the medication for nausea, vomiting, or inability to take fluids in the emergency department. No changes in the QTc are clinically significant. To date, there have been no studies evaluating the effect of ondansetron in this acutely ill population; therefore, a larger study should be completed to confirm these data.


Assuntos
Antieméticos/efeitos adversos , Eletrocardiografia/efeitos dos fármacos , Síndrome do QT Longo/induzido quimicamente , Ondansetron/efeitos adversos , Adolescente , Antieméticos/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Síndrome do QT Longo/epidemiologia , Masculino , Ondansetron/uso terapêutico , Projetos Piloto , Vômito/tratamento farmacológico
13.
Europace ; 19(8): 1378-1384, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27915262

RESUMO

AIMS: Non-fluoroscopic catheter ablation is becoming routine. In experienced centres, fluoroscopy is rarely required. The use of a traditional catheterization lab (cath lab) may no longer be necessary. We began performing catheter ablations at a paediatric centre outside the traditional cardiac cath lab in 2013. The purpose of this study was to compare procedural features of paediatric catheter ablation performed outside the cath lab to those performed within a cath lab. METHODS AND RESULTS: We prospectively looked at patients presenting to the paediatric centre with supraventricular tachycardia (SVT) undergoing catheter ablation outside the cath lab in a standard operating room (OR group). We compared retrospectively to a control group matched for age, type, and location of arrhythmia who had ablations in a traditional cath lab (CL group). Catheter visualization was exclusively by electro-anatomic mapping. Fifty-nine patients with SVT underwent catheter ablation in the OR from October 2013 to December 2015. Thirty-three patients had accessory pathways, 29 were manifest, and 13 of those were left sided. Twenty-six had atrioventricular nodal re-entrant tachycardia. Transseptal puncture with transoesophageal echocardiography guidance was used for 10 left-sided pathways, whereas the other 3 had patent foramen ovales. Procedure time did not differ significantly between groups (OR group mean 131 min, range 57-408; CL group mean 152 min, range 68-376; P = 0.12). Acute success was similar in both groups [OR group: 58/59 (98.3%) and CL group: 57/59 (96.6%)]. There were no major complications in either group. There was no fluoroscopy used in either group. CONCLUSION: Although performing paediatric catheter ablations outside the traditional cath lab is early in our experience, we produced similar outcomes and results without encountering procedural difficulties of performing ablations in a non-conventional setting. Larger multi-centred trials will be essential to determine the feasibility of this practice.


Assuntos
Cateterismo Cardíaco/métodos , Ablação por Cateter/métodos , Salas Cirúrgicas , Radiografia Intervencionista/métodos , Taquicardia Supraventricular/cirurgia , Potenciais de Ação , Adolescente , Cateterismo Cardíaco/efeitos adversos , Ablação por Cateter/efeitos adversos , Criança , Pré-Escolar , Ecocardiografia Transesofagiana , Técnicas Eletrofisiológicas Cardíacas , Feminino , Fluoroscopia , Frequência Cardíaca , Humanos , Masculino , Ohio , Duração da Cirurgia , Valor Preditivo dos Testes , Estudos Prospectivos , Radiografia Intervencionista/efeitos adversos , Estudos Retrospectivos , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
14.
Cardiol Young ; 27(3): 592-596, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27766996

RESUMO

In current practice, children with anatomically normal hearts routinely undergo fluoroscopy-free ablations. Infants and children with congenital heart disease (CHD) represent the most difficult population to perform catheter ablation without fluoroscopy. We report two neonatal patients with CHD in whom cardiac ablations were performed without fluoroscopy. The first infant had pulmonary atresia with intact ventricular septum with refractory supraventricular tachycardia, and the second infant presented with Ebstein's anomaly of the tricuspid valve along with persistent supraventricular tachycardia. Both patients underwent uncomplicated, successful ablation without recurrence of arrhythmias. These cases suggest that current approaches to minimising fluoroscopy may be useful even in challenging patients such as neonates with CHD.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Ablação por Cateter/métodos , Anomalia de Ebstein/cirurgia , Atresia Pulmonar/cirurgia , Feminino , Fluoroscopia , Cardiopatias Congênitas/cirurgia , Humanos , Recém-Nascido
15.
Ecol Indic ; 80: 84-95, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30245589

RESUMO

Cyanobacterial harmful algal blooms (cyanoHAB) cause extensive problems in lakes worldwide, including human and ecological health risks, anoxia and fish kills, and taste and odor problems. CyanoHABs are a particular concern in both recreational waters and drinking source waters because of their dense biomass and the risk of exposure to toxins. Successful cyanoHAB assessment using satellites may provide an indicator for human and ecological health protection, In this study, methods were developed to assess the utility of satellite technology for detecting cyanoHAB frequency of occurrence at locations of potential management interest. The European Space Agency's MEdium Resolution Imaging Spectrometer (MERIS) was evaluated to prepare for the equivalent series of Sentine1-3 Ocean and Land Colour Imagers (OLCI) launched in 2016 as part of the Copernicus program. Based on the 2012 National Lakes Assessment site evaluation guidelines and National Hydrography Dataset, the continental United States contains 275,897 lakes and reservoirs >1 hectare in area. Results from this study show that 5.6 % of waterbodies were resolvable by satellites with 300 m single-pixel resolution and 0.7 % of waterbodies were resolvable when a three by three pixel (3×3-pixel) array was applied based on minimum Euclidian distance from shore. Satellite data were spatially joined to U.S. public water surface intake (PWSI) locations, where single-pixel resolution resolved 57% of the PWSI locations and a 3×3-pixel array resolved 33% of the PWSI locations. Recreational and drinking water sources in Florida and Ohio were ranked from 2008 through 2011 by cyanoHAB frequency above the World Health Organization's (WHO) high threshold for risk of 100,000 cells mL-1. The ranking identified waterbodies with values above the WHO high threshold, where Lake Apopka, FL (99.1 %) and Grand Lake St. Marys, OH (83 %) had the highest observed bloom frequencies per region. The method presented here may indicate locations with high exposure to cyanoHABs and therefore can be used to assist in prioritizing management resources and actions for recreational and drinking water sources.

16.
Mol Biol Evol ; 32(10): 2749-59, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26169943

RESUMO

Genomic and transcriptomics analyses have revealed human head and body lice to be almost genetically identical; although con-specific, they nevertheless occupy distinct ecological niches and have differing feeding patterns. Most importantly, while head lice are not known to be vector competent, body lice can transmit three serious bacterial diseases; epidemictyphus, trench fever, and relapsing fever. In order to gain insights into the molecular bases for these differences, we analyzed alternative splicing (AS) using next-generation sequencing data for one strain of head lice and one strain of body lice. We identified a total of 3,598 AS events which were head or body lice specific. Exon skipping AS events were overrepresented among both head and body lice, whereas intron retention events were underrepresented in both. However, both the enrichment of exon skipping and the underrepresentation of intron retention are significantly stronger in body lice compared with head lice. Genes containing body louse-specific AS events were found to be significantly enriched for functions associated with development of the nervous system, salivary gland, trachea, and ovarian follicle cells, as well as regulation of transcription. In contrast, no functional categories were overrepresented among genes with head louse-specific AS events. Together, our results constitute the first evidence for transcript pool differences in head and body lice, providing insights into molecular adaptations that enabled human lice to adapt to clothing, and representing a powerful illustration of the pivotal role AS can play in functional adaptation.


Assuntos
Processamento Alternativo/genética , Ftirápteros/genética , Animais , Ontologia Genética , Genes de Insetos , Humanos , Pediculus/genética
17.
Anal Chem ; 88(10): 5243-50, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-27099952

RESUMO

Understanding of the penetration behaviors of pesticides in fresh produce is of great significance for effectively applying pesticides and minimizing pesticide residues in food. There is lack, however, of an effective method that can measure pesticide penetration. Herein, we developed a novel method for real-time and in situ monitoring of pesticide penetration behaviors in spinach leaves based on surface-enhanced Raman scattering (SERS) mapping. Taking advantage of penetrative gold nanoparticles (AuNPs) as probes to enhance the internalized pesticide signals in situ, we have successfully obtained the internal signals from thiabendazole, a systemic pesticide, following its penetration into spinach leaves after removing surface pesticide residues. Comparatively, ferbam, a nonsystemic pesticide, did not show internal signals after removing surface pesticide residues, demonstrating its nonsystemic behavior. In both cases, if the surface pesticides were not removed, copenetration of both AuNPs and pesticides was observed. These results demonstrate a successful application of SERS as an effective method for measuring pesticides penetration in fresh produce in situ. The information obtained could provide useful guidance for effective and safe applications of pesticides on plants.


Assuntos
Praguicidas/análise , Análise Espectral Raman , Spinacia oleracea/química , Ouro/química , Nanopartículas Metálicas/química , Praguicidas/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Spinacia oleracea/metabolismo
18.
Environ Sci Technol ; 50(12): 6216-23, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27254832

RESUMO

A model system consisting of a nonsystemic pesticide (ferbam), engineered gold nanoparticles (AuNPs) and a plant tissue (tea leaves) was investigated using surface enhanced Raman spectroscopy (SERS). Ferbam has no ability by itself to penetrate into tea leaves. When AuNPs were placed with ferbam onto the surface of tea leaves, however, the SERS signal of the ferbam-AuNPs complex was observed inside of the tea leaves. Within 1 h, the ferbam-AuNPs complex rapidly penetrated into the leaf to a depth of approximately 190 µm, about (1)/3 to (1)/2 of the leaf's thickness. The rate of penetration was dependent on the size of AuNPs, with 30 nm AuNPs-ferbam penetrating more rapidly when compared with complexes made with the 50 and 69 nm AuNPs. These results clearly demonstrated an alteration of the nonsystemic behavior of ferbam in the combined presence with AuNPs. This finding might lead to the development of some new pesticide formulations. Conversely, new toxicity issues may arise as the behaviors and fate of pesticides are altered significantly upon interaction with engineered NPs in the pesticide formulation or environment.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Praguicidas , Análise Espectral Raman , Chá
19.
Clin Orthop Relat Res ; 473(4): 1349-57, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25367108

RESUMO

BACKGROUND: Treatment options for a symptomatic, torn, irreparable, or completely ossified acetabular labrum are limited to either excision and/or reconstruction with grafts. In a previous animal model, regeneration of the acetabular labrum after excision to the bony rim has been shown. In humans, less is known about the potential of regeneration of the labrum. Recent studies seem to confirm labral regrowth, but it is still unclear if wide excision might be a surgical option in cases where repair is not possible. QUESTIONS/PURPOSES: The purposes of this study were (1) to determine the extent of acetabular labrum regeneration after excision to the bony rim; and (2) to determine whether this procedure results in higher hip scores. METHODS: We reviewed all patients treated with surgical dislocation for symptomatic femoroacetabular impingement by a single surgeon at one institution between 2003 and 2008, of whom 14 underwent wide labral excision (of at least 60°) down to bone; we used this approach when there was an absence of reparable tissue. Of these 14, nine were available for voluntary reexamination. The mean age at surgery was 38 ± 9 SD years and the mean followup was 4 ± 1 SD years. All patients consented to a physical examination and an MRI arthrogram, which was evaluated for evidence of new tissue formation by four observers. A modified Harris hip score and the UCLA were recorded. RESULTS: Regrowth of a structure equivalent to normal labrum was not observed on the MRI arthrograms. Six of nine hips had segmental defects, bone formation was found in five, and the capsule was confluent with the new tissue in six. The mean Harris hip score at latest followup was 83 ± 14, and the mean UCLA score was 6 ± 2. CONCLUSIONS: Resection of a nonreparable acetabular labrum down to a bleeding bony surface does not stimulate regrowth of tissue that appears to be capable of normal function by MR arthrography, and patients who underwent this procedure had lower hip scores at midterm than previously reported from the same institution for patients undergoing labral repair or sparse débridement. Based on these results, we believe that future studies should evaluate alternatives to reconstructing the labrum, perhaps using ligamentum teres, because resection seems neither to result in regrowth nor the restoration of consistently high hip scores.


Assuntos
Acetábulo/fisiologia , Acetábulo/cirurgia , Regeneração Óssea , Impacto Femoroacetabular/cirurgia , Acetábulo/lesões , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Ruptura
20.
Food Chem Toxicol ; 186: 114560, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432440

RESUMO

Alpha lipoic acid (ALA) is a dietary supplement that has been used to treat a wide range of diseases, including obesity and diabetes, and have lipid-lowering effects, making it a potential candidate for mitigating dyslipidemia resulting from exposures to the per- and polyfluoroalkyl substance (PFAS) family member perfluorooctanesulfonic acid (PFOS). ALA can be considered a non-fluorinated structural analog to PFOS due to their similar 8-carbon chain and amphipathic structure, but, unlike PFOS, is rapidly metabolized. PFOS has been shown to reduce pancreatic islet area and induce ß-cell lipotoxicity, indicating that changes in ß-cell lipid microenvironment is a mechanism contributing to hypomorphic islets. Due to structural similarities, we hypothesized that ALA may compete with PFOS for binding to proteins and distribution throughout the body to mitigate the effects of PFOS exposure. However, ALA alone reduced islet area and fish length, with several morphological endpoints indicating additive toxicity in the co-exposures. Individually, ALA and PFOS increased fatty acid uptake from the yolk. ALA alone increased liver lipid accumulation, altered fatty acid profiling and modulated PPARÉ£ pathway signaling. Together, this work demonstrates that ALA and PFOS have similar effects on lipid uptake and metabolism during embryonic development in zebrafish.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Ácido Tióctico , Poluentes Químicos da Água , Animais , Peixe-Zebra , Ácido Tióctico/farmacologia , Ácidos Alcanossulfônicos/toxicidade , Fluorocarbonos/toxicidade , Ácidos Graxos , Poluentes Químicos da Água/toxicidade
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