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1.
Insects ; 15(3)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38535373

RESUMO

Cabbage whitefly, Aleyrodes proletella L., is an invasive hemipteran pest of cruciferous plants, particularly field brassica crops. Its importance has been increased over the last decade, particularly in European countries. The control of cabbage whiteflies largely relies on the application of synthetic insecticides, including tetronic and tetramic acid derivatives such as spiromesifen and spirotetramat (cyclic ketoenol insecticides), acting as insect growth regulators targeting acetyl-CoA carboxylase (ACC). In 2019, reduced efficacy against cabbage whiteflies of ketoenol insecticides at recommended label rates has been reported. Subsequently we collected field samples of A. proletella in different European countries and confirmed the presence of ketoenol resistance in laboratory bioassays. Reciprocal crossing experiments revealed an autosomal dominant trait, i.e., heterozygotes express a fully resistant phenotype. Transcriptome sequencing and assembly of ACC variants from resistant strains revealed the presence of an ACC target-site mutation, A2083V, as previously described and functionally validated in Bemisia tabaci (A2084V in A. proletella). Next, we employed a molecular genotyping assay to investigate the geographic spread of resistance and analyzed 49 populations collected in eight European countries. Resistance allele frequency was highest in the Netherlands, followed by Germany. Finally, we provide a proposal for the implementation of appropriate resistance management strategies.

2.
Pest Manag Sci ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334233

RESUMO

BACKGROUND: There are various methods to control weeds, that represent considerable challenges for farmers around the globe, although applying small molecular compounds is still the most effective and versatile technology to date. In the search for novel chemical entities with new modes-of-action that can control weeds displaying resistance, we have investigated two spirocyclic classes of acyl-ACP thioesterase inhibitors based on X-ray co-crystal structures and subsequent modelling studies. RESULTS: By exploiting scaffold-hopping and isostere concepts, we were able to identify new spirolactam-based lead structures showing promising activity in vivo against commercially important grass weeds in line with strong target affinity. CONCLUSION: The present work covers a series of novel herbicidal lead structures that contain a spirocyclic lactam as a structural key feature carrying ortho-substituted benzyl or heteroarylmethylene side chains. These new compounds show good acyl-ACP thioesterase inhibition in line with strong herbicidal activity. Glasshouse trials showed that the spirolactams outlined herein display promising control of grass-weed species in pre-emergence application combined with dose-response windows that enable partial selectivity in wheat and corn. Remarkably, some of the novel acyl-ACP thioesterase-inhibitors showed efficacy against resistant grass weeds such as Alopecurus myosuroides and Lolium spp. on competitive levels compared with commercial standards. © 2024 Society of Chemical Industry.

3.
J Agric Food Chem ; 71(47): 18212-18226, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37677080

RESUMO

In the search for new chemical entities that can control resistant weeds by addressing novel modes of action (MoAs), we were interested in further exploring a compound class that contained a 1,8-naphthyridine core. By leveraging scaffold hopping methodologies, we were able to discover the new thiazolopyridine compound class that act as potent herbicidal molecules. Further biochemical investigations allowed us to identify that the thiazolopyridines inhibit acyl-acyl carrier protein (ACP) thioesterase (FAT), with this being further confirmed via an X-ray cocrystal structure. Greenhouse trials revealed that the thiazolopyridines display excellent control of grass weed species in pre-emergence application coupled with dose response windows that enable partial selectivity in certain crops.


Assuntos
Herbicidas , Herbicidas/química , Plantas Daninhas/metabolismo , Tioléster Hidrolases/metabolismo , Produtos Agrícolas/metabolismo , Controle de Plantas Daninhas/métodos
4.
J Agric Food Chem ; 71(47): 18270-18284, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37269295

RESUMO

There are several methods to control weeds, which impose particular challenges for farmers in all parts of the world, although applying small molecular compounds still remains the most efficient technology to date. However, plants can evolve to become resistant toward active ingredients which is also the case for protoporphyrinogen oxidase (PPO) inhibitors, a class of highly effective herbicides in use for more than 50 years. Hence, it is essential to continuously discover and develop new herbicidal PPO inhibitors with enhanced intrinsic activity, an improved resistance profile, enhanced crop safety, favorable physicochemical properties, and a clean toxicological profile. By modifying structural key features from known PPO inhibitors such as tiafenacil, inspired by isostere and mix&match concepts in combination with modeling investigations based on a wild-type Amaranthus crystal structure, we have found new promising lead structures showing strong activity in vitro and in vivo against several notorious dicotyledon and monocotyledon weeds with emerging resistance (e.g., Amaranthus palmeri, Amaranthus tuberculatus, Lolium rigidum, and Alopecurus myosuroides). While several phenyl uracils carrying an isoxazoline motif in their thio-linked side chain showed promising resistance-breaking potential against different Amaranthus species, introducing a thioacrylamide side chain afforded outstanding efficacy against resistant grass weeds.


Assuntos
Amaranthus , Herbicidas , Magnoliopsida , Protoporfirinogênio Oxidase/genética , Herbicidas/farmacologia , Plantas Daninhas , Poaceae , Resistência a Herbicidas
5.
Chemistry ; 29(39): e202300199, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-36807428

RESUMO

We report the design, synthesis and biological evaluation of simplified analogues of the herbicidal natural product (+)-cornexistin. Guided by an X-Ray co-crystal structure of cornexistin bound to transketolase from Zea mays, we attempted to identify the key interactions that are necessary for cornexistin to maintain its herbicidal profile. This resulted in the preparation of three novel analogues investigating the importance of substituents that are located on the nine-membered ring of cornexistin. One analogue maintained a good level of biological activity and could provide researchers insights in how to further optimize the structure of cornexistin for commercialization in the future.


Assuntos
Produtos Biológicos , Herbicidas , Herbicidas/química , Estrutura Molecular , Produtos Biológicos/química , Furanos/química , Relação Estrutura-Atividade
6.
Pest Manag Sci ; 79(6): 2264-2280, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36815643

RESUMO

BACKGROUND: Whilst there are several methods to control weeds, which continuously plague farmers around the globe, the application of small molecular compounds is still the most effective technology to date. Plants can evolve to become resistant to PPO-inhibitors, a class of herbicides in commercial use since the 1960s. It is therefore essential to continuously develop new herbicides based on this mode-of-action with enhanced intrinsic activity, an improved resistance profile and favourable physicochemical properties. Based on an Amaranthus PPO crystal structure and subsequent modelling studies, halogen-substituted pyrazoles have been investigated as isosteres of uracil-based PPO-inhibitors. RESULTS: By combining structural features from the commercial PPO-inhibitors tiafenacil and pyraflufen-ethyl and by investigating receptor-binding properties, we identified new promising pyrazole-based lead structures showing strong activity in vitro and in vivo against economically important weeds of the Amaranthus genus: A. retroflexus, and resistant A. palmeri and A. tuberculatus. CONCLUSION: The present work covers a series of novel PPO-inhibiting compounds that contain a pyrazole ring and a substituted thioacetic acid sidechain attached to the core phenyl group. These compounds show good receptor fit in line with excellent herbicidal activity against weeds that plague corn and rice crops with low application rates. This, in combination with promising selectivity in corn, have the potential to mitigate and affect weeds that have become resistant to some of the current market standards. Remarkably, some of the novel PPO-inhibitors outlined herein show efficacies against economically important weeds that were superior to recently commercialized and structurally related tiafenacil. © 2023 Society of Chemical Industry.


Assuntos
Herbicidas , Peste , Herbicidas/química , Protoporfirinogênio Oxidase , Pirazóis/farmacologia , Plantas Daninhas
7.
Front Plant Sci ; 14: 1335764, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38288413

RESUMO

Safeners are agrochemicals co-applied with herbicides that facilitate selective control of weeds by protecting monocot crops from chemical injury through enhancing the expression of detoxifying enzymes such as glutathione transferases (GSTs). Even though the application of safeners causes the induction of genes encoding GSTs in model dicots such as Arabidopsis thaliana, safeners do not protect broadleaf crops from herbicide injury. In this study, we proposed that the localized induction of Arabidopsis GSTs and the fundamental differences in their detoxifying activity between dicot and monocot species, underpin the failure of safeners to protect Arabidopsis from herbicide toxicity. Using the herbicide safener, isoxadifen-ethyl, we showed that three tau (U) family GSTs namely AtGSTU7, AtGSTU19 and AtGSTU24 were induced with different magnitude by isoxadifen treatment in root and rosette tissues. The higher magnitude of inducibility of these AtGSTUs in the root tissues coincided with the enhanced metabolism of flufenacet, a herbicide that is active in root tissue, protecting Arabidopsis plants from chemical injury. Assay of the recombinant enzyme activities and the significant reduction in flufenacet metabolism determined in the T-DNA insertion mutant of AtGSTU7 (gstu7) in Arabidopsis plants identified an important function for AtGSTU7 protein in flufenacet detoxification. In-silico structural modeling of AtGSTU7, suggested the unique high activity of this enzyme toward flufenacet was due to a less constrained active site compared to AtGSTU19 and AtGSTU24. We demonstrate here that it is possible to induce herbicide detoxification in dicotyledonous plants by safener treatment, albeit with this activity being restricted to very specific combinations of herbicide chemistry, and the localized induction of enzymes with specific detoxifying activities.

8.
JAMA Netw Open ; 5(12): e2245272, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36472870

RESUMO

Importance: Few evidence-based treatments are available for Gulf War illness (GWI). Behavioral treatments that target factors known to maintain the disability from GWI, such as problem-solving impairment, may be beneficial. Problem-solving treatment (PST) targets problem-solving impairment and is an evidence-based treatment for other conditions. Objective: To examine the efficacy of PST to reduce disability, problem-solving impairment, and physical symptoms in GWI. Design, Setting, and Participants: This multicenter randomized clinical trial conducted in the US Department of Veterans Affairs compared PST with health education in a volunteer sample of 511 Gulf War veterans with GWI and disability (January 1, 2015, to September 1, 2019); outcomes were assessed at 12 weeks and 6 months. Statistical analysis was conducted between January 1, 2019, and December 31, 2020. Interventions: Problem-solving treatment taught skills to improve problem-solving. Health education provided didactic health information. Both were delivered by telephone weekly for 12 weeks. Main Outcomes and Measures: The primary outcome was reduction from baseline to 12 weeks in self-report of disability (World Health Organization Disability Assessment Schedule). Secondary outcomes were reductions in self-report of problem-solving impairment and objective problem-solving. Exploratory outcomes were reductions in pain, pain disability, and fatigue. Results: A total of 268 veterans (mean [SD] age, 52.9 [7.3] years; 88.4% male; 66.8% White) were randomized to PST (n = 135) or health education (n = 133). Most participants completed all 12 sessions of PST (114 of 135 [84.4%]) and health education (120 of 133 [90.2%]). No difference was found between groups in reductions in disability at the end of treatment. Results suggested that PST reduced problem-solving impairment (moderate effect, 0.42; P = .01) and disability at 6 months (moderate effect, 0.39; P = .06) compared with health education. Conclusions and Relevance: In this randomized clinical trial of the efficacy of PST for GWI, no difference was found between groups in reduction in disability at 12 weeks. Problem-solving treatment had high adherence and reduced problem-solving impairment and potentially reduced disability at 6 months compared with health education. These findings should be confirmed in future studies. Trial Registration: ClinicalTrials.gov Identifier: NCT02161133.


Assuntos
Guerra do Golfo , Síndrome do Golfo Pérsico , Estados Unidos , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Autorrelato , Síndrome do Golfo Pérsico/terapia , Educação em Saúde , Dor
9.
Sci Rep ; 12(1): 7221, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508530

RESUMO

The development of drug resistance by Mycobacterium tuberculosis and other pathogenic bacteria emphasizes the need for new antibiotics. Unlike animals, most bacteria synthesize isoprenoid precursors through the MEP pathway. 1-Deoxy-D-xylulose 5-phosphate synthase (DXPS) catalyzes the first reaction of the MEP pathway and is an attractive target for the development of new antibiotics. We report here the successful use of a loop truncation to crystallize and solve the first DXPS structures of a pathogen, namely M. tuberculosis (MtDXPS). The main difference found to other DXPS structures is in the active site where a highly coordinated water was found, showing a new mechanism for the enamine-intermediate stabilization. Unlike other DXPS structures, a "fork-like" motif could be identified in the enamine structure, using a different residue for the interaction with the cofactor, potentially leading to a decrease in the stability of the intermediate. In addition, electron density suggesting a phosphate group could be found close to the active site, provides new evidence for the D-GAP binding site. These results provide the opportunity to improve or develop new inhibitors specific for MtDXPS through structure-based drug design.


Assuntos
Mycobacterium tuberculosis , Animais , Antibacterianos/farmacologia , Sítios de Ligação , Mycobacterium tuberculosis/metabolismo , Pentosefosfatos , Transferases/metabolismo
10.
Life Sci ; 282: 119805, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34237313

RESUMO

AIMS: Widespread pain and headache are common in Gulf War Illness with suboptimal treatments available. We tested the efficacy of non-invasive, transcutaneous vagal nerve stimulation (nVNS) for relief of widespread pain and migraine in Gulf War Veterans with GWI. MAIN METHODS: A 10-week double-blind, randomized controlled trial of nVNS used the gammaCore (ElectroCore, Inc.) compared to sham stimulation with the same device followed by a 10-week open-label follow up with active nVNS. The primary outcome was a numerical pain rating at the end of the blinded period. Secondary outcomes included physical function, migraine frequency and severity, and impression of change during the blinded and open-label periods. Two-factor MANOVA models tested for significant differences between groups from baseline to end of the blinded period and during the open-label period. KEY FINDINGS: Among 27 participants enrolled and issued a nVNS device, there was a slight improvement in pain ratings from baseline to the end of the blinded phase [6.18 (±0.82) vs. 5.05 (±2.3); p = 0.040] which did not differ between active and sham nVNS. Physical function was also slightly improved overall without group differences. There were no significant changes in migraine frequency or severity during the blinded period. Twenty participants started in the open-label phase; no statistically significant changes in pain, physical function, migraine measures, or impression of change were noted during this phase. SIGNIFICANCE: Veterans with GWI actively treated with nVNS reported no improvement in either widespread pain or migraine frequency or severity relative to Veterans with GWI who received sham nVNS.


Assuntos
Dor Crônica/terapia , Síndrome do Golfo Pérsico/terapia , Estimulação do Nervo Vago/métodos , Adulto , Dor Crônica/etiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome do Golfo Pérsico/complicações , Resultado do Tratamento , Estimulação do Nervo Vago/efeitos adversos , Estimulação do Nervo Vago/instrumentação , Veteranos
11.
Biochem Biophys Res Commun ; 539: 42-47, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33421767

RESUMO

In this report, we describe a truncated Deinococcus radiodurans 1-deoxy-D-xylulose-5-phosphate synthase (DXS) protein that retains enzymatic activity, while slowing protein degradation and showing improved crystallization properties. With modern drug-design approaches relying heavily on the elucidation of atomic interactions of potential new drugs with their targets, the need for co-crystal structures with the compounds of interest is high. DXS itself is a promising drug target, as it catalyzes the first reaction in the 2-C-methyl-D-erythritol 4-phosphate (MEP)-pathway for the biosynthesis of the universal precursors of terpenes, which are essential secondary metabolites. In contrast to many bacteria and pathogens, which employ the MEP pathway, mammals use the distinct mevalonate-pathway for the biosynthesis of these precursors, which makes all enzymes of the MEP-pathway potential new targets for the development of anti-infectives. However, crystallization of DXS has proven to be challenging: while the first X-ray structures from Escherichia coli and D. radiodurans were solved in 2004, since then only two additions have been made in 2019 that were obtained under anoxic conditions. The presented site of truncation can potentially also be transferred to other homologues, opening up the possibility for the determination of crystal structures from pathogenic species, which until now could not be crystallized. This manuscript also provides a further example that truncation of a variable region of a protein can lead to improved structural data.


Assuntos
Deinococcus/enzimologia , Escherichia coli/enzimologia , Proteínas Mutantes/química , Transferases/química , Sequência de Aminoácidos , Cristalografia por Raios X/métodos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutação , Elementos Estruturais de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência , Transferases/genética , Transferases/metabolismo
12.
Bioorg Med Chem ; 28(22): 115725, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-33007548

RESUMO

New phosphorous-containing lead structures against drought stress in crops interacting with RCAR/(PYR/PYL) receptor proteins were identified starting from in-depth SAR studies of related sulfonamide lead structures and protein docking studies. A converging 6-step synthesis via phosphinic chlorides and phosphono chloridates as key intermediates afforded envisaged tetrahydroquinolinyl phosphinamidates and phosphonamidates. Whilst tetrahydroquinolinyl phosphonamidates 13a,b exhibited low to moderate target affinities, the corresponding tetrahydroquinolinyl phosphinamidates 12a,b revealed confirmed strong affinities for RCAR/ (PYR/PYL) receptor proteins in Arabidopsis thaliana on the same level as essential plant hormone abscisic acid (ABA) combined with promising efficacy against drought stress in vivo (broad-acre crops wheat and canola).


Assuntos
Amidas/farmacologia , Produtos Agrícolas/efeitos dos fármacos , Secas , Compostos Organofosforados/farmacologia , Proteínas de Plantas/química , Quinolinas/farmacologia , Ácido Abscísico/metabolismo , Amidas/química , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Produtos Agrícolas/metabolismo , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos Organofosforados/química , Proteínas de Plantas/metabolismo , Quinolinas/química , Relação Estrutura-Atividade
13.
Physiol Rep ; 8(17): e14564, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32889791

RESUMO

Two consecutive maximal cardiopulmonary exercise tests (CPETs) performed 24 hr apart (2-day CPET protocol) are increasingly used to evaluate post-exertional malaise (PEM) and related disability among individuals with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). This protocol may extend to other fatiguing illnesses with similar characteristics to ME/CFS; however, 2-day CPET protocol reliability and minimum change required to be considered clinically meaningful (i.e., exceeding the standard error of the measure) are not well characterized. To address this gap, we evaluated the 2-day CPET protocol in Gulf War Illness (GWI) by quantifying repeatability of seven CPET parameters, establishing their thresholds of clinically significant change, and determining whether changes differed between veterans with GWI and controls. Excluding those not attaining peak effort criteria (n = 15), we calculated intraclass correlation coefficients (ICCs), the smallest real difference (SRD%), and repeated measures analysis of variance (RM-ANOVA) at the ventilatory anaerobic threshold (VAT) and peak exercise in 15 veterans with GWI and eight controls. ICC values at peak ranged from moderate to excellent for veterans with GWI (mean [range]; 0.84 [0.65 - 0.92]) and were reduced at the VAT (0.68 [0.37 - 0.78]). Across CPET variables, the SRD% at peak exercise for veterans with GWI (18.8 [8.8 - 28.8]) was generally lower than at the VAT (28.1 [9.5 - 34.8]). RM-ANOVAs did not detect any significant group-by-time interactions (all p > .05). The methods and findings reported here provide a framework for evaluating 2-day CPET reliability, and reinforce the importance of carefully considering measurement error in the population of interest when interpreting findings.


Assuntos
Teste de Esforço/métodos , Fadiga/fisiopatologia , Síndrome do Golfo Pérsico/fisiopatologia , Adulto , Limiar Anaeróbio , Aptidão Cardiorrespiratória , Teste de Esforço/normas , Fadiga/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome do Golfo Pérsico/diagnóstico
14.
Pest Manag Sci ; 76(10): 3377-3388, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32034864

RESUMO

BACKGROUND: Aclonifen is a unique diphenyl ether herbicide. Despite its structural similarities to known inhibitors of the protoporphyrinogen oxidase (e.g. acifluorfen, bifenox or oxadiazon), which result in leaf necrosis, aclonifen causes a different phenotype that is described as bleaching. This also is reflected by the Herbicide Resistance Action Committee (HRAC) classification that categorizes aclonifen as an inhibitor of pigment biosynthesis with an unknown target. RESULTS: A comprehensive Arabidopsis thaliana RNAseq dataset comprising 49 different inhibitor treatments and covering 40 known target pathways was used to predict the aclonifen mode of action (MoA) by a random forest classifier. The classifier predicts for aclonifen a MoA within the carotenoid biosynthesis pathway similar to the reference compound norflurazon that inhibits the phytoene desaturase. Upon aclonifen treatment, the phytoene desaturation reaction is disturbed, resulting in a characteristic phytoene accumulation in vivo. However, direct enzyme inhibition by the herbicide was excluded for known herbicidal targets such as phytoene desaturase, 4-hydroxyphenylpyruvate dioxygenase and homogentisate solanesyltransferase. Eventually, the solanesyl diphosphate synthase (SPS), providing one of the two homogentisate solanesyltransferase substrate molecules, could be identified as the molecular target of aclonifen. Inhibition was confirmed using biochemical activity assays for the A. thaliana SPSs 1 and 2. Furthermore, a Chlamydomonas reinhardtii homolog was used for co-crystallization of the enzyme-inhibitor complex, showing that one inhibitor molecule binds at the interface between two protein monomers. CONCLUSION: Solanesyl diphosphate synthase was identified as the target of aclonifen, representing a novel mode of action for herbicides. © 2020 Society of Chemical Industry.


Assuntos
Compostos de Anilina/farmacologia , Alquil e Aril Transferases , Resistência a Herbicidas , Herbicidas
15.
PLoS One ; 14(11): e0224833, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31714907

RESUMO

INTRODUCTION: The components of minute ventilation, respiratory frequency and tidal volume, appear differentially regulated and thereby afford unique insight into the ventilatory response to exercise. However, respiratory frequency and tidal volume are infrequently reported, and have not previously been considered among military veterans with Gulf War Illness. Our purpose was to evaluate respiratory frequency and tidal volume in response to a maximal cardiopulmonary exercise test in individuals with and without Gulf War Illness. MATERIALS AND METHODS: 20 cases with Gulf War Illness and 14 controls participated in this study and performed maximal cardiopulmonary exercise test on a cycle ergometer. Ventilatory variables (minute ventilation, respiratory frequency and tidal volume) were obtained and normalized to peak exercise capacity. Using mixed-design analysis of variance models, with group and time as factors, we analyzed exercise ventilatory patterns for the entire sample and for 11 subjects from each group matched for race, age, sex, and height. RESULTS: Despite similar minute ventilation (p = 0.57, η2p = 0.01), tidal volume was greater (p = 0.02, η2p = 0.16) and respiratory frequency was lower (p = 0.004, η2p = 0.24) in Veterans with Gulf War Illness than controls. The findings for respiratory frequency remained significant in the matched subgroup (p = 0.004, η2p = 0.35). CONCLUSION: In our sample, veterans with Gulf War Illness adopt a unique exercise ventilatory pattern characterized by reduced respiratory frequency, despite similar ventilation relative to controls. Although the mechanism(s) by which this pattern is achieved remains unresolved, our findings suggest that the components of ventilation should be considered when evaluating clinical conditions with unexplained exertional symptoms.


Assuntos
Teste de Esforço , Guerra do Golfo , Respiração , Veteranos , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato , Volume de Ventilação Pulmonar , Fatores de Tempo , Ventilação
16.
Bioorg Med Chem ; 27(24): 115142, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31685332

RESUMO

Novel synthetic lead structures interacting with RCAR/(PYR/PYL) receptor proteins were identified based on the results of a high-throughput screening campaign of a large compound library followed by focused SAR studies of the three most promising hit clusters. Whilst indolinylmethyl sulfonamides 8y,z and phenylsulfonyl ethylenediamines 9y,z showed strong affinities for RCAR/ (PYR/PYL) receptor proteins in wheat, thiotriazolyl acetamides 7f,s exhibited promising efficacy against drought stress in vivo (wheat, corn and canola) combined with confirmed target interaction in wheat and arabidopsis thaliana. Remarkably, binding affinities of several representatives of 8 and 9 were on the same level or even better than the essential plant hormone abscisic acid (ABA).


Assuntos
Ácido Abscísico/análogos & derivados , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/química , Ácido Abscísico/química , Ácido Abscísico/farmacologia , Produtos Agrícolas , Secas , Descoberta de Drogas , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Estrutura Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ligação Proteica , Sulfonamidas , Triticum/genética , Triticum/metabolismo
17.
Ann Med ; 51(7-8): 371-378, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31642345

RESUMO

Objective: To determine if presence of co-existing medically unexplained syndromes or psychiatric diagnoses affect symptom frequency, severity or activity impairment in Chronic Fatigue Syndrome.Patients: Sequential Chronic Fatigue Syndrome patients presenting in one clinical practice.Design: Participants underwent a psychiatric diagnostic interview and were evaluated for fibromyalgia, irritable bowel syndrome and/or multiple chemical sensitivity.Main Measures: Structured Clinical Interview [SCID] for DSM-IV; SF-36, Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Short Form; Patient Health Questionnaire-8; Multidimensional Fatigue Inventory (MFI-20), CDC Symptom InventoryResults: Current and lifetime psychiatric diagnosis was common (68%) increasing mental fatigue/health but no other illness variables and not with diagnosis of other medically unexplained syndromes. 81% of patients had at least one of these conditions with about a third having all three co-existing syndromes. Psychiatric diagnosis was not associated with their diagnosis. Increasing the number of these unexplained conditions was associated with increasing impairment in physical function, pain and rates of being unable to work.Conclusions: Patients with Chronic Fatigue Syndrome should be evaluated for current psychiatric conditions because of their impact on patient quality of life, but they do not act as a symptom multiplier for the illness. Other co-existing medically unexplained syndromes are more common than psychiatric co-morbidities in patients presenting for evaluation of medically unexplained fatigue and are also more associated with increased disability and the number and severity of symptoms.Key messagesWhen physicians see patients with medically unexplained fatigue, they often infer that this illness is due to an underlying psychiatric problem.This paper shows that the presence of co-existing psychiatric diagnoses does not impact on any aspect of the phenomenology of medically unexplained fatigue also known as chronic fatigue syndrome. Therefore, psychiatric status is not an important causal contributor to CFS.In contrast, the presence of other medically unexplained syndromes (irritable bowel syndrome; fibromyalgia and/or multiple chemical sensitivity) do impact on the illness such that the more of these that co-exist the more health-related burdens the patient has.


Assuntos
Síndrome de Fadiga Crônica/epidemiologia , Transtornos Mentais/epidemiologia , Adulto , Comorbidade , Síndrome de Fadiga Crônica/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia
18.
J Occup Environ Med ; 60(12): e663-e670, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30308619

RESUMO

OBJECTIVE: The aim of this study was to assess the neurobehavioral effects of lifetime solvent exposure by comparing the performance of painters and demographically comparable controls. METHODS: Performance of exposed painters (N = 133) was compared with unexposed tapers, glaziers, or carpenters (N = 78) on the following domains: motor/perceptual speed, visual contrast, attention, working memory/planning, and visual and verbal memory. Lifetime exposure was estimated with questionnaires, field measurements, and paint composition. RESULTS: After controlling for confounders, lifetime solvent exposure did not predict reduction in performance for overall domains of function. Lifetime solvent exposures predicted subtle alterations for individual tests of verbal learning, motor coordination, and visuospatial accuracy. CONCLUSION: Concentrations of solvents in paints have steadily declined during the working lifetime of subjects in this study. Although reduced performance was observed on individual tests, these alterations were not consistent across tests and unlikely to be of clinical significance.


Assuntos
Indústria da Construção , Doenças do Sistema Nervoso/etiologia , Exposição Ocupacional/efeitos adversos , Pintura , Solventes/toxicidade , Adulto , Atenção , Sensibilidades de Contraste , Feminino , Humanos , Masculino , Memória de Curto Prazo , Pessoa de Meia-Idade , Testes Neuropsicológicos , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Tempo de Reação
19.
J Chem Inf Model ; 58(8): 1625-1637, 2018 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-30036062

RESUMO

Water molecules are of great importance for the correct representation of ligand binding interactions. Throughout the last years, water molecules and their integration into drug design strategies have received increasing attention. Nowadays a variety of tools are available to place and score water molecules. However, the most frequently applied software solutions require substantial computational resources. In addition, none of the existing methods has been rigorously evaluated on the basis of a large number of diverse protein complexes. Therefore, we present a novel method for placing water molecules, called WarPP, based on interaction geometries previously derived from protein crystal structures. Using a large, previously compiled, high-quality validation set of almost 1500 protein-ligand complexes containing almost 20 000 crystallographically observed water molecules in their active sites, we validated our placement strategy. We correctly placed 80% of the water molecules within 1.0 Šof a crystallographically observed one.


Assuntos
Proteínas/química , Água/química , Sítios de Ligação , Bases de Dados de Proteínas , Ligantes , Modelos Moleculares , Conformação Proteica , Termodinâmica
20.
Behav Sci (Basel) ; 8(2)2018 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-29439541

RESUMO

Creation is an important part of many interventions in creative arts therapies (art, music, dance, and drama therapy). This active part of art-making in arts therapies has not yet been closely investigated. The present study commits to this field of research using a mixed-methods design to investigate the effects of active creation on health-related psychological outcomes. In an artistic inquiry within an experimental design, N = 44 participants engaged in active art-making for eight minutes in the presence of the researcher (first author) with a choice of artistic materials: paper and colors for drawing and writing, musical instruments, space for moving or performing. Before and after the creation, participants completed a well-being, a self-efficacy and an experience of creation scale, and in addition found their own words to express the experiences during the activity. We hypothesized that the experience of empowerment, freedom, impact, and creativity (Experience of Creation Scale) mediates the positive effect of active creation on the outcomes of self-efficacy and well-being, and evaluated this assumption with a mediation analysis. Results suggest that the effect of active creation on both self-efficacy and well-being is significantly mediated by the Experience of Creation Scale. This article focuses on the quantitative side of the investigation. During the process, qualitative and quantitative results were triangulated for a more valid evaluation and jointly contribute to the emerging theory frame of embodied aesthetics.

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