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1.
Nano Lett ; 2024 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-39462259

RESUMO

Research on current-induced domain wall (DW) motion in heavy metal/ferromagnet structures is crucial for advancing memory, logic, and computing devices. Here, we demonstrate that adjusting the angle between the DW conduit and the current direction provides an additional degree of control over the current-induced DW motion. A DW conduit with a 45° section relative to the current direction enables asymmetrical DW behavior: for one DW polarity, motion proceeds freely, while for the opposite polarity, motion is impeded or even blocked in the 45° zone, depending on the interfacial Dzyaloshinskii-Moriya interaction strength. This enables the device to function as a DW diode. Leveraging this velocity asymmetry, we designed a Y-shaped DW conduit with one input and two output branches at +45° and -45°, functioning as a DW selector. A DW injected into the junction exits through one branch, while a reverse polarity DW exits through the other, demonstrating selective DW routing.

2.
Mov Disord ; 39(10): 1740-1751, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39192744

RESUMO

BACKGROUND: Parkinson's disease (PD) has been consistently linked to alterations within the gut microbiome. OBJECTIVE: Our goal was to identify microbial features associated with PD incidence and progression. METHODS: Metagenomic sequencing was used to characterize taxonomic and functional changes to the PD microbiome and to explore their relation to bacterial metabolites and disease progression. Motor and non-motor symptoms were tracked using Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) and levodopa equivalent dose across ≤5 yearly study visits. Stool samples were collected at baseline for metagenomic sequencing (176 PD, 100 controls). RESULTS: PD-derived stool samples had reduced intermicrobial connectivity and seven differentially abundant species compared to controls. A suite of bacterial functions differed between PD and controls, including depletion of carbohydrate degradation pathways and enrichment of ribosomal genes. Faecalibacterium prausnitzii-specific reads contributed significantly to more than half of all differentially abundant functional terms. A subset of disease-associated functional terms correlated with faster progression of MDS-UPDRS part IV and separated those with slow and fast progression with moderate accuracy within a random forest model (area under curve = 0.70). Most PD-associated microbial trends were stronger in those with symmetric motor symptoms. CONCLUSION: We provide further evidence that the PD microbiome is characterized by reduced intermicrobial communication and a shift to proteolytic metabolism in lieu of short-chain fatty acid production, and suggest that these microbial alterations may be relevant to disease progression. We also describe how our results support the existence of gut-first versus brain-first PD subtypes. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Fezes , Microbioma Gastrointestinal , Metagenômica , Doença de Parkinson , Humanos , Doença de Parkinson/microbiologia , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Metagenômica/métodos , Fezes/microbiologia , Progressão da Doença
3.
Glia ; 70(5): 820-841, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35019164

RESUMO

Fecal-oral contamination promotes malnutrition pathology. Lasting consequences of early life malnutrition include cognitive impairment, but the underlying pathology and influence of gut microbes remain largely unknown. Here, we utilize an established murine model combining malnutrition and iterative exposure to fecal commensals (MAL-BG). The MAL-BG model was analyzed in comparison to malnourished (MAL mice) and healthy (CON mice) controls. Malnourished mice display poor spatial memory and learning plasticity, as well as altered microglia, non-neuronal CNS cells that regulate neuroimmune responses and brain plasticity. Chronic fecal-oral exposures shaped microglial morphology and transcriptional profile, promoting phagocytic features in MAL-BG mice. Unexpectedly, these changes occurred independently from significant cytokine-induced inflammation or blood-brain barrier (BBB) disruption, key gut-brain pathways. Metabolomic profiling of the MAL-BG cortex revealed altered polyunsaturated fatty acid (PUFA) profiles and systemic lipoxidative stress. In contrast, supplementation with an ω3 PUFA/antioxidant-associated diet (PAO) mitigated cognitive deficits within the MAL-BG model. These findings provide valued insight into the malnourished gut microbiota-brain axis, highlighting PUFA metabolism as a potential therapeutic target.


Assuntos
Microbioma Gastrointestinal , Desnutrição , Animais , Cognição , Microbioma Gastrointestinal/fisiologia , Desnutrição/complicações , Camundongos , Camundongos Endogâmicos C57BL , Microglia
4.
Mov Disord ; 35(7): 1208-1217, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32357258

RESUMO

BACKGROUND: Parkinson's disease is characterized by a high burden of gastrointestinal comorbidities, especially constipation and reduced colonic transit time, and by gut microbiota alterations. The diverse metabolites produced by the microbiota are broadly relevant to host health. How microbiota composition and metabolism relate to gastrointestinal function in Parkinson's disease is largely unknown. The objectives of the current study were to assesses associations between microbiota composition, stool consistency, constipation, and systemic microbial metabolites in Parkinson's disease to better understand how intestinal microbes contribute to gastrointestinal disturbances commonly observed in patients. METHODS: Three hundred participants (197 Parkinson's patients and 103 controls) were recruited for this cross-sectional cohort study. Participants supplied fecal samples for microbiota sequencing (n = 300) and serum for untargeted metabolomics (n = 125). Data were collected on motor and nonmotor Parkinson's symptoms, medications, diet, and demographics. RESULTS: Significant microbiota taxonomic differences were observed in Parkinson's patients, even when controlling for gastrointestinal function. Parkinson's microbiota was characterized by reduced carbohydrate fermentation and butyrate synthesis capacity and increased proteolytic fermentation and production of deleterious amino acid metabolites, including p-cresol and phenylacetylglutamine. Taxonomic shifts and elevated proteolytic metabolites were strongly associated with stool consistency (a proxy for colonic transit time) and constipation among patients. CONCLUSIONS: Compositional and metabolic alterations in the Parkinson's microbiota are highly associated with gut function, suggesting plausible mechanistic links between altered bacterial metabolism and reduced gut health in this disease. The systemic detection of elevated deleterious proteolytic microbial metabolites in Parkinson's serum suggests a mechanism whereby microbiota dysbiosis contributes to disease etiology and pathophysiology. © 2020 International Parkinson and Movement Disorder Society.


Assuntos
Microbioma Gastrointestinal , Doença de Parkinson , Estudos Transversais , Disbiose , Trato Gastrointestinal , Humanos , Doença de Parkinson/complicações
5.
Omega (Westport) ; 80(4): 568-591, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29249171

RESUMO

Cross-culturally, dead are protected from posthumous negative evaluations by the universal "nil nisi bonum" precept that governs the ethics within the community of mourners. In this study, we set out to test the observance of this injunction against posthumous gossiping in the Romanian public deathscape. Obituaries and other posthumous articles (N = 1,148) were collected that covered the deaths of 63 celebrities who passed away between 2013 and 2016. Materials were gathered from the digital archives of three Romanian news sources (a news agency, a "quality" newspaper, and a tabloid), published one week after the moment of death. The findings show that 22% of the articles do contain negative evaluations of the deceased. The percentage rises to 36.4% if we restrict the sample to only those celebrities with a controversial anthumous reputation (19 of 63). These results indicate that celebrities are not spared from critical assessments after they pass away.


Assuntos
Comunicação , Pessoas Famosas , Humanos , Romênia
6.
Pak J Med Sci ; 33(1): 111-120, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367183

RESUMO

OBJECTIVES: This study aimed at assessing the incidence of pulmonary hypertension (PH) at newly diagnosed hyperthyroid patients and at finding a simple model showing the complex functional relation between pulmonary hypertension in hyperthyroidism and the factors causing it. METHODS: The 53 hyperthyroid patients (H-group) were evaluated mainly by using an echocardiographical method and compared with 35 euthyroid (E-group) and 25 healthy people (C-group). In order to identify the factors causing pulmonary hypertension the statistical method of comparing the values of arithmetical means is used. The functional relation between the two random variables (PAPs and each of the factors determining it within our research study) can be expressed by linear or non-linear function. By applying the linear regression method described by a first-degree equation the line of regression (linear model) has been determined; by applying the non-linear regression method described by a second degree equation, a parabola-type curve of regression (non-linear or polynomial model) has been determined. We made the comparison and the validation of these two models by calculating the determination coefficient (criterion 1), the comparison of residuals (criterion 2), application of AIC criterion (criterion 3) and use of F-test (criterion 4). RESULTS: From the H-group, 47% have pulmonary hypertension completely reversible when obtaining euthyroidism. The factors causing pulmonary hypertension were identified: previously known- level of free thyroxin, pulmonary vascular resistance, cardiac output; new factors identified in this study- pretreatment period, age, systolic blood pressure. According to the four criteria and to the clinical judgment, we consider that the polynomial model (graphically parabola- type) is better than the linear one. CONCLUSIONS: The better model showing the functional relation between the pulmonary hypertension in hyperthyroidism and the factors identified in this study is given by a polynomial equation of second degree where the parabola is its graphical representation.

8.
J Org Chem ; 78(9): 4214-30, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23270408

RESUMO

Lithium diisopropylamide (LDA)-mediated ortholithiations of 2-fluoropyridine and 2,6-difluoropyridine in tetrahydrofuran at -78 °C were studied using a combination of IR and NMR spectroscopic and computational methods. Rate studies show that a substrate-assisted deaggregation of LDA dimer occurs parallel to an unprecedented tetramer-based pathway. Standard and competitive isotope effects confirm post-rate-limiting proton transfer. Autocatalysis stems from ArLi-catalyzed deaggregation of LDA proceeding via 2:2 LDA-ArLi mixed tetramers. A hypersensitivity of the ortholithiation rates to traces of LiCl derives from LiCl-catalyzed LDA dimer-monomer exchange and a subsequent monomer-based ortholithiation. Fleeting 2:2 LDA-LiCl mixed tetramers are suggested to be key intermediates. The mechanisms of both the uncatalyzed and catalyzed deaggregations are discussed. A general mechanistic paradigm is delineated to explain a number of seemingly disparate LDA-mediated reactions, all of which occur in tetrahydrofuran at -78 °C.


Assuntos
Lítio/química , Compostos Organometálicos/química , Propilaminas/química , Piridinas/química , Catálise , Cinética , Cloreto de Lítio/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
9.
J Alzheimers Dis ; 87(1): 247-258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35275538

RESUMO

BACKGROUND: Despite decades of research, our understanding of Alzheimer's disease (AD) etiology remains incomplete. In recent years, appreciation has grown for potential roles for the microbiota in shaping neurological health. OBJECTIVE: This study aimed to examine associations between the microbiota and AD in a human cross-sectional cohort. METHODS: Forty-five AD patients and 54 matched controls were recruited in Vancouver, Canada. Fecal and oral samples underwent 16S microbiota sequencing. A wide array of demographic and clinical data were collected. Differences between participant groups were assessed, and associations between microbes and clinical variables were examined within the AD population. RESULTS: The gut microbiota of AD patients displayed lower diversity relative to controls, although taxonomic differences were sparse. In contrast, the AD oral microbiota displayed higher diversity, with several taxonomic differences relative to controls, including a lower abundance of the families Streptococcaceae and Actinomycetaceae, and a higher abundance of Weeksellaceae, among others. The periodontitis-associated oral microbe Porphyromonas gingivalis was 5 times more prevalent among patients. No significant associations between gut or oral microbes and cognition were detected, but several correlations existed between microbes and mood disorders and BMI among patients, including a strong positive correlation between Alphaproteobacteria and depression score. CONCLUSION: The gut microbiota of AD patients was not overtly different from controls, although it displayed lower diversity, an overall marker of microbiota health. The oral microbiota did display marked differences. Cognition was not associated with a microbial signature, but other relevant AD factors including mood and BMI did demonstrate an association.


Assuntos
Doença de Alzheimer , Microbiota , Doença de Alzheimer/microbiologia , Canadá/epidemiologia , Estudos Transversais , Humanos , RNA Ribossômico 16S/genética
10.
J Parkinsons Dis ; 11(1): 153-158, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33164944

RESUMO

The gut microbiome has been increasingly implicated in Parkinson's disease (PD); however, most existing studies employ bacterial-specific sequencing, and have not investigated non-bacterial microbiome constituents. Here, we use fungal-specific internal transcribed spacer (ITS)-2 amplicon sequencing in a cross-sectional PD cohort to investigate associations between the fungal gut microbiome and PD. Fungal load among participants was extremely low, and genera identified were almost exclusively of proposed dietary or environmental origin. We observed significantly lower fungal DNA relative to bacterial DNA among PD patients. No fungi differed in abundance between patients and controls, nor were any associated with motor, cognitive, or gastrointestinal features among patients.


Assuntos
DNA Bacteriano , DNA Fúngico , Microbioma Gastrointestinal , Micobioma , Doença de Parkinson/microbiologia , Idoso , Estudos Transversais , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA
11.
J Am Chem Soc ; 132(18): 6361-5, 2010 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-20397635

RESUMO

Treatment of 2,6-difluoropyridine with lithium diisopropylamide in THF solution at -78 degrees C effects ortholithiation quantitatively. Warming the solution to 0 degrees C converts the aryllithium to 2-fluoro-6-(diisopropylamino)pyridine. Rate studies reveal evidence of a reversal of the ortholithiation and a subsequent 1,2-addition via two monomer-based pathways of stoichiometries [ArH*i-Pr(2)NLi(THF)](double dagger) and [ArH*i-Pr(2)NLi(THF)(3)](double dagger). Computational studies fill in the structural details and provide evidence of a direct substitution without the intermediacy of a Meisenheimer complex.


Assuntos
Propilaminas/química , Piridinas/química , Cinética , Soluções , Espectrofotometria Infravermelho , Temperatura
12.
Nephrol Dial Transplant ; 24(11): 3441-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19509025

RESUMO

BACKGROUND: The creation of arteriovenous fistulas (AVF) in patients with advanced chronic kidney disease (CKD) has been shown to have adverse effects on their central pulse wave profile suggesting a likely increase in arterial stiffness. The aim of the present study was to directly evaluate the effect of AVF on arterial stiffness. Method. Thirty-one stage-5 CKD patients underwent haemodynamic assessment prior to and 3 months after creation of AVF. Haemodynamic assessment included measurement of blood pressure (BP), central and carotidal pulse wave profile analysis, and carotido-femoral and carotido-radial pulse wave velocities (PWV). Pre-AVF and post-AVF haemodynamic parameters were compared using the Wilcoxon signed-rank test or the paired Student t-test as appropriate. Pearson correlations, single and multiple linear regressions, were used to determine the association between variables. RESULTS: After creation of AVF, peripheral and central BPs decreased without significant change in heart rate (HR) or pulse pressure. Carotido-femoral PWV ((c-f)PWV) fell from 13.2 +/- 4.1 to 11.7 +/- 3.1 m/s (P < 0.001). There was an increase in the central augmentation index (20.8% +/- 11.5 versus 23.7% +/- 11.6, P = 0.07) of borderline significance, and a significant reduction in the subendocardial viability ratio (153% +/- 34 versus 143% +/- 32, P < 0.05), which was mainly the result of a decrease in the diastolic pressure time index (DPTI) without any significant change in the diastolic duration. The reduction of (c-f)PWV was explained by changes in mean BP and HR (R(2) = 0.29). The reduction in DPTI was related to changes in central diastolic BP and changes in end-systolic BP (adjusted R(2) = 0.87). The significant improvement in aortic stiffness was mostly the result of the relative reduction of (c-f)PWV in the subgroup of patients with baseline (c-f)PWV above the median value of 13 m/s. CONCLUSION: The creation of AVF is associated with a passive improvement of aortic stiffness especially in patients with stiffer arteries. This improvement in arterial stiffness could potentially be beneficial to the cardiovascular system despite an associated deterioration in the aortic pulse wave profile.


Assuntos
Aorta/fisiopatologia , Derivação Arteriovenosa Cirúrgica , Nefropatias/fisiopatologia , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Doença Crônica , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade
13.
Sci Rep ; 9(1): 18798, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31827211

RESUMO

We herein report on the synthesis by a facile sol-gel method without templates for preparing rutile RuxTi1-xO2 (x = 0.16; 0.07; 0.01) nanobelts with exposed (001) facets. The rutile nanobelts with exposure (001) facets, favor the separation photogenerated electron-hole pairs and inhibit the recombination of the electron-hole pairs resulting in the increase of the number of main superoxide and hydroxyl radicals. The photocatalytic properties of the rutile RuxTi1-xO2 nanobelts were evaluated by discoloring of MB (methylene blue) dye under sunlight irradiation at an intensity of 40000 lx. It was also done a thorough interface analysis to determine the band energy.

14.
EBioMedicine ; 38: 257-264, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30473376

RESUMO

BACKGROUND: Reduced activity of proprotein convertase subtilisin/kexin type 9 (PCSK9) has been associated with decreased short-term death in patients with septic shock. Whether PCSK9 genotype influences long-term outcomes in sepsis survivors is unknown. METHODS: We evaluated the impact of PCSK9 loss-of-function (LOF) genotype on both 1-year mortality and infection-related readmission (IRR) after an index sepsis admission. The Derivation cohort included 342 patients who survived 28 days after a sepsis admission in a tertiary hospital (Vancouver/Canada, 2004-2014), while an independent Validation cohort included 1079 septic shock patients admitted at the same hospital (2000-2006). All patients were genotyped for three common missense PCSK9 LOF variants rs11591147, rs11583680, rs562556 and were classified in 3 groups: Wildtype, single PCSK9 LOF, and multiple PCSK9 LOF, according to the number of LOF alleles per patient. We also performed a meta-analysis using both cohorts to investigate the effects of PCSK9 genotype on 90-day survival. FINDINGS: In the Derivation cohort, patients carrying multiple PCSK9 LOF alleles showed lower risk for the composite outcome 1-year death or IRR (HR: 0.40, P = 0.006), accelerated reduction on neutrophil counts (P = 0.010), and decreased levels of PCSK9 (P = 0.037) compared with WT/single LOF groups. Our meta-analysis revealed that the presence of multiple LOF alleles was associated with lower 90-day mortality risk (OR = 0.69, P = 0.020). INTERPRETATION: The presence of multiple PCSK9 LOF alleles decreased the risk of 1-year death or IRR in sepsis survivors. Biological measures suggest this may be related to an enhanced resolution of the initial infection. FUNDING: Canadian Institutes of Health Research (PJT-156056).


Assuntos
Genótipo , Mutação com Perda de Função , Pró-Proteína Convertase 9/genética , Sepse/etiologia , Sepse/mortalidade , Adulto , Idoso , Alelos , Biomarcadores , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Readmissão do Paciente , Polimorfismo de Nucleotídeo Único , Prognóstico , Recidiva , Estudos Retrospectivos , Sepse/diagnóstico , Sepse/metabolismo , Fatores de Tempo
15.
J Innate Immun ; 8(2): 211-20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26756586

RESUMO

PURPOSE: We have recently shown that PCSK9 reduces the clearance of endotoxin and is therefore a critical regulator of the innate immune response during infection. However, plasma PCSK9 levels during human sepsis and their relationship to outcomes are not known. Our objective was to determine the relationship between plasma PCSK9 levels and the rate of endotoxin clearance, and then correlate PCSK9 levels with the development of acute organ failures in a cohort of patients with sepsis. METHODS: Using human hepatocyte cells, we determined the threshold at which PCSK9 is able to reduce Escherichia coli endotoxin uptake by cultured human hepatocytes. In a single-centre observational cohort at St. Paul's Hospital in Vancouver, Canada, we recruited 200 patients who activated our Emergency Department's sepsis protocol and measured plasma PCSK9 and lipid levels at triage and throughout the admission. Outcomes were the development of sepsis-induced cardiovascular or respiratory failure. RESULTS: We reviewed the literature and determined that the normal human range of PCSK9 found in plasma is 170-220 ng/ml, while levels of 250 ng/ml and above reduced E. coli endotoxin clearance in cultured human hepatocytes. In septic patients, the median levels associated with new-onset respiratory and cardiovascular failure were 370 (250-500) and 380 (270-530) ng/ml, respectively, versus 270 (220-380) ng/ml in patients who did not go on to develop any organ failure (p = 0.003 and 0.005, respectively). CONCLUSIONS: Plasma PCSK9 levels are greatly increased in sepsis. At normal levels, PCSK9 has no influence upon hepatocyte bacterial endotoxin clearance, but as levels rise, there is a progressive inhibition of clearance. During sepsis, PCSK9 levels are highly correlated with the development of subsequent multiple organ failure. Inhibition of PCSK9 activity is an attractive target for treating the spectrum of sepsis and septic shock.


Assuntos
Endotoxinas/sangue , Insuficiência de Múltiplos Órgãos/sangue , Pró-Proteína Convertase 9/sangue , Sepse/sangue , Linhagem Celular , Endotoxinas/imunologia , Feminino , Hepatócitos/imunologia , Hepatócitos/metabolismo , Humanos , Masculino , Insuficiência de Múltiplos Órgãos/imunologia , Insuficiência de Múltiplos Órgãos/terapia , Pró-Proteína Convertase 9/imunologia , Sepse/imunologia , Sepse/terapia
16.
Org Lett ; 7(9): 1829-32, 2005 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-15844917

RESUMO

[reaction: see text] A simplified synthesis of N-heterocyclic carbene (NHC)Pd-carboxylate complexes and their activity in Suzuki-Miyaura cross-coupling reactions are described. Coupling of sterically hindered aryl and activated alkyl chlorides bearing beta-hydrogens has been successfully achieved.

17.
Org Lett ; 4(23): 4053-6, 2002 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-12423084

RESUMO

A number of palladium-N-heterocyclic carbene (NHC) complexes were found to be active catalysts for the arylation of ketones. A large number of substrates, both aryl halides and ketones, are compatible with the reaction conditions. The ketone arylation reactions are achieved with low catalyst loading in short reaction times using aryl chlorides and triflates as reactive partners. [reaction: see text]

18.
Org Lett ; 4(13): 2229-31, 2002 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-12074674

RESUMO

[reaction: see text] The synthesis and characterization of [Pd(IPr)Cl(2)](2) (1), an air- and moisture-stable complex, is reported. The utilization of 1 as a catalyst for amination of aryl chlorides and bromides with a variety of amine coupling partners under mild conditions is described. The amination reactions with 1 show a remarkable insensitivity to oxygen and water, and thus the amination reactions could be performed in air on the benchtop with undried reagent grade solvents and substrates with small effects on reaction times and conversions.

19.
Org Lett ; 5(9): 1479-82, 2003 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-12713303

RESUMO

Palladacycle dimers possessing bridging halides can be easily cleaved by using N-heterocyclic carbenes (NHCs) to generate novel monomeric complexes. The structure of one of these was determined by single-crystal diffraction study and consists of a square-planar coordination around the palladium center where the NHC ligand is trans to the amine of the palladacycle. The complex was found to be equally active in aryl amination and alpha-arylation of ketones even at very low catalyst loading (0.02 mol %). Primary and secondary alkyl/arylamines are equally active partners in coupling reactions. [reaction: see text]

20.
Artigo em Inglês | MEDLINE | ID: mdl-25392580

RESUMO

BACKGROUND: Given its numerous biologically active components, Euphorbiaceae has been found to be a large plant family and polyvalent with quite interesting therapeutic activity that can be studied. MATERIALS AND METHODS: The ixodicidal activity of Euphorbia cyparissias extracts was studied in vitro and in vivo. Tested concentrations were 10, 5, 2, 1, 0.5 and 0.25%. RESULTS: For the in vitro study, conducted on field-collected female specimens of Dermacentor marginatus and Haemaphysalis punctata, the efficacy results showed that the ticks died after exposure in the case of 10, 5, and 2% tincture concentrations. The effects appeared after 30 minutes and became more visible 120 minutes after each exposure. The statistical differences regarding the used concentrations were found to be: F = 6.51, df = 5, P < 0.001. The in vivo study of the efficacy of E. cyparissias concentrations was performed on 35 naturally infested sheep and on 30 bovines parasitized with Ixodes ricinus, sprayed with tincture and glycerinate dilutions (bovines) on days 0 and 7. The results revealed detrimental effects on the survivability of female ticks, the most prominent being the reduction of their movement capacity. In sheep in vivo efficiency observed within 24 hrs varied, between 1 and 23% for D. marginatus and between 7 and 27% for H. punctata and respectively between 2 and 53% after 24 hrs, for I. ricinus, comparable effects being also found 72 hrs after the second administration of Euphorbia extracts. CONCLUSION: Extracts from E. cyparissias may be used, with results, as an ecologic alternative tick control management method, being a cheap solution, with a sizeable role in reducing the use of synthetic and/or other harming and resistance source ixodicidal conditionings.


Assuntos
Doenças dos Bovinos/parasitologia , Euphorbia , Inseticidas/farmacologia , Ixodidae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Doenças dos Ovinos/parasitologia , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Feminino , Fitoterapia , Ovinos , Doenças dos Ovinos/prevenção & controle
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