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1.
Angew Chem Int Ed Engl ; 63(7): e202317683, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38150265

RESUMO

Herein, we report the use of isonitriles as alkyl radical precursors in light-mediated hydro- and deuterodeamination reactions. The reaction is scalable, shows broad functional group compatibility and potential to be used in late-stage functionalization. Importantly, the method is general for Cα -primary, Cα -secondary and Cα -tertiary alkyl isonitriles. For most examples, high yields were obtained through direct visible-light irradiation of the isonitrile in the presence of a silyl radical precursor. Interestingly, in the presence of an organic photocatalyst (4CzIPN) a dramatic acceleration was observed. In-depth mechanistic studies using UV/Vis absorption, steady-state and time-resolved photoluminescence, and transient absorption spectroscopy suggest that the excited state of 4CzIPN can engage in a single-electron transfer with the isonitrile.

2.
Molecules ; 28(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37959735

RESUMO

The 5,8-disubstituted indolizidines are the largest family of indolizidines isolated from the skin of amphibians. These compounds exhibit interesting biological activities such as noncompetitive blockers of nicotinic receptors. In this paper, we present a short, simple, and general synthesis of these alkaloids based on the hetero Diels-Alder reaction between suitable monoactivated dienes and Δ1-pyrroline as the dienophile. The selectivity of the process is explained based on computational studies. Concise synthesis of the indolizidine alkaloid 181B from a hetero Diels-Alder reaction was accomplished in four steps.

3.
J Org Chem ; 87(7): 4981-4990, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35289617

RESUMO

The preparation of nonanomeric C-acyl-saccharides has been developed from two different carboxylic acid feedstocks. This transformation is driven by the synergistic interaction of an electron donor-acceptor complex and Ni catalysis. Primary-, secondary-, and tertiary redox-active esters are incorporated as coupling partners onto preactivated pyranosyl- and furanosyl acids, preserving their stereochemical integrity. The reaction occurs under mild conditions, without stoichiometric metal reductants or exogenous catalysts, using commercially available Hantzsch ester as the organic photoreductant.


Assuntos
Níquel , Substâncias Redutoras , Elétrons , Glicosídeos , Estrutura Molecular
4.
Environ Geochem Health ; 44(3): 729-747, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34047883

RESUMO

The mineralogical and geochemical characterization of sediments of the Reconquista River allows analyzing the geochemical partition of trace elements in one of the most polluted water courses of Argentina. The low dissolved oxygen and high ammonia contents, together with the high chemical oxygen demand, attest to the poor water quality. Ammonia, Cd and Cu content in surficial water exceeds the maximum guidelines for freshwater in Argentina. The recent sediments of the uppermost bed are enriched in organic matter (OM), sulfur, Zn, Cu and Pb. The enrichment factor is moderate, and the geoaccumulation index (Igeo) for Cu and Pb indicates uncontaminated to moderately contaminated sediments. The positive and significant correlation between As, Cr, Pb and Zn with the iron content suggests that their retention is controlled by the amount of iron oxy (hydr)oxides in the sediments, probably combined with the silt + clay abundance. In comparison with its tributary, the Las Catonas Stream, the Reconquista River, has less OM and trace elements in the sediments and more dissolved trace elements in the interstitial water. We interpret that OM is the main sorbent of the trace element. In the absence of OM, the iron oxy (hydr)oxides and the silt + clay fraction are a less efficient substitute. Consequently, the interstitial waters of the Reconquista River are enriched in these elements. Therefore, minor changes in the environmental conditions may generate significant release of hazardous trace elements from the sediments to the interstitial water and, in turn, to the surficial water of the river. As most of the big cities and the agricultural activities of Argentina are developed on the loessic substrate, the understanding of its interaction with polluted waters is crucial.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Argentina , Monitoramento Ambiental , Sedimentos Geológicos/química , Metais Pesados/análise , Rios/química , Oligoelementos/análise , Poluentes Químicos da Água/análise
5.
Angew Chem Int Ed Engl ; 61(22): e202202706, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35294095

RESUMO

The synthesis of sulfides has been widely studied because this functional subunit is prevalent in biomolecules and pharmaceuticals, as well as being a useful synthetic platform for further elaboration. Thus, various methods to build C-S bonds have been developed, but typically they require the use of precious metals or harsh conditions. Electron donor-acceptor (EDA) complex photoactivation strategies have emerged as versatile and sustainable ways to achieve C-S bond formation, avoiding challenges associated with previous methods. This work describes an open-to-air, photoinduced, site-selective C-H thioetherification from readily available reagents via EDA complex formation that tolerates a wide range of different functional groups. Moreover, C(sp2 )-halogen bonds remain intact using this protocol, allowing late-stage installation of the sulfide motif in various bioactive scaffolds, while allowing yet further modification through more traditional C-X bond cleavage protocols. Additionally, various mechanistic investigations support the envisioned EDA complex scenario.


Assuntos
Elétrons , Sais , Halogênios , Metais , Oxidantes
6.
Acta Obstet Gynecol Scand ; 100(6): 1075-1081, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33319355

RESUMO

INTRODUCTION: The role of intrapartum ultrasound as an ancillary method to instrumental vaginal delivery is yet to be determined. This study aimed to compare the use of transabdominal and transperineal ultrasound with routine clinical care before performing an instrumental vaginal delivery, regarding the incidence of adverse maternal and neonatal outcomes. MATERIAL AND METHODS: A randomized controlled trial was conducted between October 2016 and March 2019 in two tertiary care maternity hospitals in Lisbon, Portugal. Women at term, with full cervical dilatation, singleton fetuses in cephalic presentation, and with an established indication for instrumental vaginal delivery, were approached for enrollment. After informed consent was obtained, randomization into one of two groups was carried out. In the experimental arm, women underwent transabdominal ultrasound for determination of the fetal head position and transperineal ultrasound for evaluation of the angle of progression, before instrumental vaginal delivery. In the control arm, no ultrasound was carried out before instrumental vaginal delivery. Primary outcomes were composite measures of maternal and neonatal morbidity. Composite maternal morbidity consisted of severe postpartum hemorrhage, perineal trauma, and prolonged hospital stay. Composite neonatal morbidity consisted of low 5-minute Apgar score, umbilical artery metabolic acidosis, birth trauma, and neonatal intensive care unit admission. RESULTS: A total of 222 women were enrolled (113 in the experimental arm and 109 in the control arm). No significant differences between the two arms were found in composite measures of maternal (23.9% in the experimental group vs 22.9% in the control group, odds ratio 1.055, 95% CI 0.567-1.964) or neonatal morbidity (9.7% in the experimental group vs 6.4% in the control group, odds ratio 1.571, 95% CI 0.586-4.215), nor in any of the individual outcomes. CONCLUSIONS: In this small randomized controlled trial that was stopped for futility before reaching the required sample size, transabdominal and transperineal ultrasound performed just before instrumental vaginal delivery did not reduce the incidence of adverse maternal and neonatal outcomes, when compared with routine clinical care.


Assuntos
Apresentação no Trabalho de Parto , Segunda Fase do Trabalho de Parto/fisiologia , Resultado da Gravidez/epidemiologia , Ultrassonografia Pré-Natal/métodos , Vácuo-Extração/métodos , Adulto , Feminino , Humanos , Recém-Nascido , Complicações do Trabalho de Parto/epidemiologia , Gravidez , Artérias Umbilicais/diagnóstico por imagem
7.
Ecotoxicol Environ Saf ; 187: 109673, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31698196

RESUMO

The herbicide glyphosate [N- (phosphonomethyl) glycine; PMG] and the insecticide chlorpyrifos [O, O-diethyl O- (3,5,6-trichloro-2-pyridinyl) -phosphorothioate, CPF] are widely used in agricultural practices around the world and can reach aquatic environments. Therefore, it is necessary to characterize the toxicity of these pesticides on non-target species. The use of biomarkers as a tool to assess responses of organisms exposed to pollutants requires the understanding of their natural fluctuation and the dose-response relationship. In the present work, the effect of the exposure to PMG and CPF on the acetylcholinesterase activity (AChE, biomarker of neurotoxicity) in Cnesterodon decemmaculatus, a native teleost, was evaluated in different environmental conditions. Semi-static bioassays of acute toxicity were carried out under controlled conditions during the four weather seasons of the year using animals of homogeneous size. Circannual rhythms in the basal levels of AChE activity in homogenates of the anterior section were confirmed. Statistically significant average inhibition of AChE activity (47.1 ±â€¯0.7% for 1 µg CPF × L-1; 69.7 ±â€¯2.5% for 5 µg CPF × L-1; 23.1 ±â€¯1.1% for 1 mg PMG × L-1 and 32.9 ±â€¯3.3% for 10 mg PMG × L-1) was determined during summer, winter and spring weather seasons. Interestingly, animals exhibit an increased susceptibility to exposure during the autumn season (inhibition of 55.4 ±â€¯0.6% for 1 µg CPF × L-1; 81.9 ±â€¯3.3% for 5 µg CPF × L-1; 41.4 ±â€¯1.7% for 1 mg PMG × L-1 and 61.1 ±â€¯0.3% for 10 mg PMG × L-1). A different sensitivity of the enzyme between seasons was evaluated by in vitro tests. The inhibition pattern for chlorpyrifos-oxon (CPF-oxon, the active metabolite of CPF) was not affected when test was performed using homogenates of unexposed specimens of summer or autumn. Otherwise, PMG in vitro inhibitory effect was not observed in a wide range of concentrations. The results confirm that AChE activity is a sensitive biomarker for exposure to CPF and PMG, even at environmentally relevant concentrations. Finally, this work highlights the existence of seasonal variations in the dose-response relationship, which could be due to variations in the metabolism of the pollutants.


Assuntos
Acetilcolinesterase/metabolismo , Clorpirifos/análogos & derivados , Inibidores da Colinesterase/toxicidade , Ciprinodontiformes/metabolismo , Glicina/análogos & derivados , Estações do Ano , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Clorpirifos/toxicidade , Relação Dose-Resposta a Droga , Água Doce/química , Glicina/toxicidade , Glifosato
8.
AAPS PharmSciTech ; 21(7): 274, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33033873

RESUMO

Biopharmaceuticals are usually administered intravenously with frequent dosing regimens which may decrease patient compliance. Controlled-release formulations allow to reduce the frequency of injections while providing a constant dosing of the biopharmaceutical over extended periods. These formulations are typically produced by emulsions, requiring high amounts of organic solvents and have limited productivity. Hot-melt extrusion (HME) is an alternative technology to produce controlled drug delivery systems. It is a continuous solvent-free process, leading to a small ecological footprint and higher productivity. However, it may induce thermolabile compounds' degradation. In this work, the impact of the formulation and extrusion temperature on lysozyme's bioactivity and release profile of poly(lactic-co-glycolic acid) (PLGA)-based extended release formulations were evaluated using a design-of-experiments (DoE) approach. The lysozyme-loaded PLGA microparticles were produced by HME followed by milling. It was observed that the in vitro release (IVR) profile was mainly affected by the drug load; higher drug load led to higher burst and total lysozyme release after 14 days. HME temperature seemed to decrease lysozyme's activity although this correlation was not statistically significant (p value = 0.0490). Adding polyethylene glycol 400 (PEG 400) as a plasticizer to the formulation had no significant impact on the lysozyme release profile. The burst release was effectively mitigated with the inclusion of a washing step. Washing the microparticles with water reduced the burst release by 80% whereas washing them with a poly(vinyl alcohol) (PVA) aqueous solution eliminated it. In conclusion, HME is demonstrated to be suitable in producing controlled-release microparticles of small biopharmaceuticals. Graphical abstract.


Assuntos
Preparações de Ação Retardada , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Tecnologia de Extrusão por Fusão a Quente/métodos , Muramidase/química , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Emulsões , Muramidase/administração & dosagem , Solventes/química
9.
Bull Environ Contam Toxicol ; 105(6): 835-840, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33159532

RESUMO

Gills represent one of the major sites of gas exchange of fish, consequently they are in continuous close contact with the aquatic environment and its pollutants. In the present study the effects on gills of pejerrey fish, Odontesthes bonariensis, under glyphosate-based herbicide subchronic exposure were analyzed. Adult animals were exposed to sublethal concentrations of a glyphosate-based commercial formulation (1 and 10 PMG mg L-1, PMG: glyphosate active ingredient) for 15 days, while control group was maintained in rearing water. Ultrastructural changes in gills were observed by scanning electron microscopy (SEM). The composition of the surface epithelium and specific surface area were determined by energy dispersive spectroscopy (EDS) and N2 (g) adsorption-desorption isotherms, respectively. The herbicide exposure induced severe alterations in gill ultrastructure, as shown in the SEM micrographs. Accordingly, an increase in surface area of the gills of exposed animals was determined. These results support that gills parameters of freshwater fish are sensitive morphological biomarkers for glyphosate exposure.


Assuntos
Peixes/fisiologia , Herbicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Água Doce , Brânquias/efeitos dos fármacos , Glicina/análogos & derivados , Testes de Toxicidade Subcrônica , Glifosato
10.
Ecotoxicol Environ Saf ; 172: 471-479, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30738229

RESUMO

The effects of a commercial glyphosate formulation on the oxidative stress parameters and morphology (including the ultrastructure) of the phytoplanktonic green microalga Scenedesmus vacuolatus were evaluated. After 96 h of exposure to increasing herbicide concentrations (0, 4, 6, 8 mg L-1 active ingredient) with the addition of alkyl aryl polyglycol ether surfactant, the growth of the cultures decreased (96 h-IC50- 4.90 mg L-1) and metabolic and morphology alterations were observed. Significant increases in cellular volume (103-353%) and dry weight (105%) and a significant decrease in pigment content (41-48%) were detected. Oxidative stress parameters were significantly affected, showing an increase in the reactive oxygen species (ROS) and reduced glutathione (GSH) contents, oxidative damage to lipids and proteins and a decrease in the activities of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) and the detoxifying enzyme glutathione-S-transferase (GST). Cells exposed to glyphosate formulation were larger and showed an increase in vacuole size, bleaching, cell wall thickening and alteration of the stacking pattern of thylakoids. The results of this study showed the participation of oxidative stress in the mechanism of toxic action of the commercial glyphosate formulation on S. vacuolatus and the relation between the biochemical, morphological and ultrastructure alterations.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Scenedesmus/efeitos dos fármacos , Scenedesmus/metabolismo , Scenedesmus/ultraestrutura , Animais , Catalase/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Glicina/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo , Glifosato
11.
Sensors (Basel) ; 19(5)2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30871122

RESUMO

Since the first studies of luminescent sensors based on metal organic frameworks (MOFs) about ten years ago, there has been an increased interest in the development of specific sensors towards cations, anions, explosives, small molecules, solvents, etc. However, the detection of toxic compounds related to agro-industry and nuclear activity is noticeably scarce or even non-existent. In this work, we report the synthesis and characterization of luminescent lanthanide-based MOFs (Ln-MOFs) with diverse crystalline architectures obtained by solvothermal methods. The luminescent properties of the lanthanides, and the hypersensitive transitions of Eu3+ (5D0→7F2) and Tb3+ (5D4→7F5) intrinsically found in the obtained MOFs in particular, were evaluated and employed as chemical sensors for agrochemical and cationic species. The limit of detection (LOD) of Tb-PSA MOFs (PSA = 2-phenylsuccinate) was 2.9 ppm for [UO22+] and 5.6 ppm for [Cu2+]. The variations of the 4f⁻4f spectral lines and the quenching/enhancement effects of the Ln-MOFs in the presence of the analytes were fully analyzed and discussed in terms of a combinatorial "host⁻guest" vibrational and "in-silico" interaction studies.

12.
Molecules ; 24(18)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533331

RESUMO

In this work, we studied carbon paste electrodes (CPEs) with two kinds of binders: mineral oil or ionic liquids (IL) derived from N-substituted octyl pyridinium bis(trifluoromethylsulfonyl)imide with the substituents H-, CH3-, CN- and CF3-. The work aims to study this series of IL and determine a possible effect of the substituent of the cation in the behavior of the IL as a binder of graphite for obtaining IL-CPEs. The electrochemical response and the electrical behavior were measured by cyclic voltammetry and electrochemical impedance spectroscopy, respectively. Surprisingly, the substituent does not affect the cyclic voltammetry response because in all the cases, high resistance and high capacitive currents were obtained. The best response in terms of conductivity is obtained by CPE. In the case of impedance measurements, the substituent does not cause differences, and in all the cases, the IL-CPEs show nearly the same responses. CPE shows lower capacitance and higher resistance for diffusion compared to the IL-CPEs due to his lower porosity. The high resistance showed by the IL-CPEs by cyclic voltammetry can be attributed to poorly intermolecular forces among graphite, water, electrolyte, and ILs as demonstrated by theoretical calculations.


Assuntos
Carbono/química , Condutividade Elétrica , Eletroquímica , Eletrodos , Líquidos Iônicos/química , Modelos Teóricos , Algoritmos , Estrutura Molecular
13.
J Environ Sci Health B ; 54(4): 281-289, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30755089

RESUMO

The picloram (PCM) adsorption on nontronite, illite and kaolinite was studied at pH 3, 5 and 7. The adsorption isotherms had well-fitted to Langmuir and Freundlich models equations. The interactions of PCM with the clay mineral surfaces exhibited an anionic profile adsorption, with a decrease in adsorption when the pH increases. The PCM adsorption capacity increases in the following order: kaolinite < illite < nontronite. The X-ray diffraction (XRD) analysis of PCM-clay samples revealed that the picloram molecule does not enter into the clays basal space. The interaction of PCM with clays surface sites through nitrogen of the pyridine ring was confirmed by X-ray photoelectron spectroscopy (XPS). Due to the anionic form of PCM, the adsorption onto the external and edges surface sites of the clay minerals was proposed.


Assuntos
Argila/química , Caulim/química , Minerais/química , Picloram/isolamento & purificação , Adsorção , Herbicidas/química , Herbicidas/isolamento & purificação , Concentração de Íons de Hidrogênio , Espectroscopia Fotoeletrônica , Picloram/química , Difração de Raios X
14.
J Sep Sci ; 41(12): 2613-2622, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29663672

RESUMO

A microdispersive solid-phase extraction method has been developed using multiwalled carbon nanotubes of 110-170 nm diameter and 5-9 µm length for the extraction of a group of nine phthalic acid esters (i.e., bis(2-methoxyethyl) phthalate, bis-2-ethoxyethyl phthalate, dipropyl phthalate, butylbenzyl phthalate, bis-2-n-butoxyethyl phthalate, bis-isopentyl phthalate, bis-n-pentyl phthalate, dicyclohexyl phthalate, and di-n-octyl phthalate) from tap water as well as from different beverages commercialized in plastic bottles (mineral water, lemon- and apple-flavored mineral water, and an isotonic drink). Determination was carried out by high-performance liquid chromatography coupled to mass spectrometry. The extraction procedure was optimized following a step-by-step approach, being the optimum extraction conditions: 50 mL of each sample at pH 6.0, 80 mg of sorbent, and 25 mL of acetonitrile as elution solvent. To validate the methodology, matrix-matched calibration and a recovery study were developed, obtaining determination coefficients >0.9906 and absolute recovery values between 70 and 117% (with relative standard deviations < 17%) in all cases. The limits of quantification of the method were between 0.173 and 1.45 µg/L. After the evaluation of the matrix effects, real samples were also analyzed, finding butylbenzyl phthalate in all samples (except in apple-flavored mineral water), though at concentrations below its limit of quantification of the method.


Assuntos
Bebidas/análise , Ácidos Ftálicos/análise , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Espectrometria de Massas , Nanotubos de Carbono/química , Extração em Fase Sólida/instrumentação , Água/química
15.
J Minim Invasive Gynecol ; 23(3): 404-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26767825

RESUMO

STUDY OBJECTIVE: Total hysterectomy with bilateral salpingo-oophorectomy and vaginectomy for genital reassignment surgery is a complex procedure that is usually performed with a combined vaginal and abdominal approach. The aim of this study was to describe the feasibility of laparoscopic vaginectomy in sex reassignment surgery. METHODS: We reviewed the relevant medical history, intra/postoperative complications, and surgical results of all patients diagnosed with gender dysphoria and submitted to totally laparoscopic gender confirmation surgery in our department between January 2007 and March 2015. In total, 23 patients underwent total hysterectomy with bilateral salpingo-oophorectomy and vaginectomy in a single intervention. The vaginal mucosa was conserved to be used for the penile neourethra during the subsequent phalloplasty. MEASUREMENTS AND MAIN RESULTS: The surgeries had an average operating time of 155 ± 42 minutes. No intraoperative complications were registered. In all patients, the vagina was totally removed, and, in most cases (n = 20), we were able to remove laparoscopically more than 50% of the vagina. Three patients had postoperative complications. One patient presented with hemoperitoneum on the second postoperative day; another presented with prolonged urinary retention, and a third patient developed a perineal hematoma 1 month after surgery. Patients were discharged less than 72 hours after surgery, except the patient who developed a postoperative hemoperitoneum. For all patients, we obtained an adequate specimen of vaginal mucosa to reconstruct the penile neourethra for the subsequent phalloplasty. CONCLUSION: This study suggests the feasibility of laparoscopic vaginectomy in genital reassignment surgery. The procedure can be executed as a continuation of the hysterectomy with the potential advantage of the laparoscopy providing better exposure of the anatomic structures with low blood losses (less than 500 mL) and few complications. Furthermore, using this approach, adequate-sized vaginal mucosa flaps were obtained for the urethral reconstruction.


Assuntos
Procedimentos Cirúrgicos em Ginecologia , Histerectomia Vaginal , Histerectomia , Laparoscopia , Cirurgia de Readequação Sexual/métodos , Uretra/cirurgia , Vagina/cirurgia , Abdome/cirurgia , Adulto , Animais , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Tubas Uterinas/cirurgia , Estudos de Viabilidade , Feminino , Procedimentos Cirúrgicos em Ginecologia/instrumentação , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Histerectomia/métodos , Histerectomia Vaginal/métodos , Laparoscopia/métodos , Masculino , Ovariectomia/métodos , Complicações Pós-Operatórias/etiologia , Cirurgia de Readequação Sexual/instrumentação , Resultado do Tratamento
16.
Parasitol Res ; 115(3): 1339-44, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26691858

RESUMO

Phlebotomine sand flies (Diptera, Psychodidae) are vectors of multiple Leishmania species, among which Leishmania infantum stands out as a being frequently pathogenic to humans and dogs in Mediterranean countries. In this study, Sergentomyia minuta sand flies were collected using CDC miniature light traps in different 431 biotopes from Southwest Spain. A total of 114 females were tested for the presence of Leishmania DNA by targeting ITS-1 and cyt-B sequences by PCR. Leishmania DNA was detected in one S. minuta. Characterization of the obtained DNA sequences by phylogenetic analyses revealed close relatedness with Leishmania tarentolae Wenyon, 1921 as well as with both human and canine pathogenic strains of Asian origin (China), previously described as Leishmania sp. To our knowledge, this is the first report of phlebotomine sand flies naturally infected with L. tarentolae-like in Spain. The possible infection of sand flies with novel Leishmania species should be taken into consideration in epidemiological studies of vector species in areas where leishmaniosis is endemic.


Assuntos
DNA de Protozoário/genética , Leishmania/genética , Leishmaniose/parasitologia , Psychodidae/parasitologia , Animais , DNA de Protozoário/isolamento & purificação , Feminino , Humanos , Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose/epidemiologia , Filogenia , Reação em Cadeia da Polimerase , Espanha/epidemiologia
17.
J Sep Sci ; 38(15): 2692-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26012850

RESUMO

In this work, we have compared the selectivity of two commercial molecularly imprinted polymers (AFFINIMIP®SPE Estrogens and AFFINIMIP®SPE Zearalenone) for the extraction of 12 estrogenic compounds of interest (i.e. 17α-estradiol, 17ß-estradiol, estrone, hexestrol, 17α-ethynylestradiol, diethylstibestrol, dienestrol, zearalenone, α-zearalanol, ß-zearalanol, α-zearalenol and ß-zearalenol) from different water samples. High-performance liquid chromatography coupled with ion trap mass spectrometry with electrospray ionization was used for their determination. Results showed that although both molecularly imprinted polymeric cartridges were specifically designed for different groups of analytes (natural estrogens like estradiol in the first case and zearalenone derivatives in the second) they nearly have the same extraction performance (with recovery values in the range 65-101%) for the same analytes in Milli-Q water because of the cross-reactivity of the polymer. However, when more complex water samples were analyzed, it was clear that the behavior was different and that the AFFINIMIP®SPE Estrogens showed less cross-reactivity than the other cartridge. Validation of the proposed methodology with both cartridges revealed that the extraction was reproducible and that the final limits of detection of the proposed method were in the low ng/L range.

18.
Ecotoxicol Environ Saf ; 111: 236-41, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25450939

RESUMO

The use of biomarkers as a tool to assess responses of organisms exposed to pollutants in toxicity bioassays, as well as in aquatic environmental risk assessment protocols, requires the understanding of the natural fluctuation of the particular biomarker. The aim of this study was to characterize the intrinsic variations of acetylcholinesterase (AChE) activity in tissues of a native freshwater teleost fish to be used as biomarker in toxicity tests, taking into account both seasonal influence and fish size. Specific AChE activity was measured by the method of Ellman et al. (1961) in homogenates of fish anterior section finding a seasonal variability. The highest activity was observed in summer, decreasing significantly below 40% in winter. The annual AChE activity cycle in the anterior section was fitted to a sinusoidal function with a period of 11.2 months. Moreover, an inverse relationship between enzymatic activity and the animal size was established. The results showed that both the fish length and seasonal variability affect AChE activity. AChE activity in fish posterior section showed a similar trend to that in the anterior section, while seasonal variations of the activity in midsection were observed but differences were not statistically significant. In addition, no relationship between AChE and total tissue protein was established in the anterior and posterior sections suggesting that the circannual rhythms observed are AChE-specific responses. Results highlight the importance of considering both the fish size and season variations to reach valid conclusions when AChE activity is employed as neurotoxicity biomarker.


Assuntos
Acetilcolinesterase/metabolismo , Ciprinodontiformes/metabolismo , Monitoramento Ambiental/métodos , Fotoperíodo , Estações do Ano , Animais , Biomarcadores/metabolismo , Tamanho Corporal , Água Doce , Temperatura , Poluentes Químicos da Água/toxicidade
19.
Ecotoxicol Environ Saf ; 114: 157-63, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25637751

RESUMO

Water pollution by agrochemicals is currently one of the most critical problems for the conservation of aquatic ecosystems. Glyphosate [N-(phosphonomethyl) glycine); PMG] is the main broad-spectrum post emergence herbicide used for the control of a wide range of pests in soybean crops. Adenylate energy charge (AEC) reflects the energy balance of the cells, a measure of the energy available from the adenylate pool: adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP). Background adenylates, phosphagens and the AEC index of two year old Odontesthes bonariensis were determined in some tissues by HPLC, and the impact on subcellular energy balance of sublethal glyphosate-based herbicide exposure was analyzed. The doses used were 0 (control tank), 1 or 10mg PMGL(-1), trials were carried out during 15 days. AEC values in brain, liver and muscle from control fish were 0.37 ± 0.02, 0.49 ± 0.05 and 0.56 ± 0.03, respectively (means ± SEM). While brain ATP concentrations were undetectable (hence low values of AEC), the muscle tissue showed the highest concentrations of the more energetic molecules: 0.18 µmole ATP g(-1) and 8 µmole phosphocreatine g(-1) (PCrg(-1)). In the brain, no significant changes were detected in exposed fish compared to controls. Instead, in both the liver and muscle of animals exposed to the highest concentration of the herbicide, significant changes in the AEC (reduction of 26% and 15%, p<0.05) with respect to the control group were determined. Chronic exposure (15 days) of Odontesthes bonariensis to 1 and 10mgL(-1) of formulated glyphosate did not affect brain AEC. However, the highest concentration of the herbicide produced a significant decrease in liver and muscle AEC manifesting adverse sublethal effects on the energy metabolism. These results suggest the usefulness of AEC as a biomarker of fish glyphosate exposure.


Assuntos
Nucleotídeos de Adenina/metabolismo , Metabolismo Energético/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/toxicidade , Smegmamorpha , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Glicina/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo , Músculos/metabolismo , Fosfocreatina/metabolismo , Smegmamorpha/metabolismo , Glifosato
20.
Arch Gynecol Obstet ; 290(6): 1121-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25033717

RESUMO

OBJECTIVE: This study aimed at evaluating the effect of vaginal intercourse on spontaneous labor onset at term. METHODS: In a randomized controlled trial, patients with singleton, cephalic, term, and low-risk pregnancy were assigned to either vaginal intercourse at least twice a week or abstinence. The following data were assessed: demographics, parity, vaginal coitus frequency before and during pregnancy, Bishop score at 38th weeks, gestational age at delivery, mode of delivery, and days between recruitment and delivery. The primary outcome was spontaneous labor onset. RESULTS: Of the 123 patient analyzed, 63 were assigned to study group and 60 to control group. Mean interval between study recruitment and delivery was higher in sexually active women (15.05 days ± 0.8 compared with 14.17 days ± 0.8, p = 0.45) as well as the rate of cesarean delivery (14.3 % compared with 10 %, p = 0.58), but the differences were not statistically significant. The rate of spontaneous labor was similar in both groups (84.1 % in vaginal coitus group; 75 % in control group, p = 0.26). CONCLUSION: Our results showed that vaginal intercourse does not hasten spontaneous labor onset at term.


Assuntos
Coito , Parto Obstétrico , Trabalho de Parto , Abstinência Sexual , Nascimento a Termo , Adulto , Feminino , Idade Gestacional , Humanos , Paridade , Gravidez , Resultado da Gravidez , Adulto Jovem
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