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1.
Environ Toxicol ; 39(7): 3856-3871, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38558378

RESUMO

Discharges to the aquatic environment of pharmaceuticals represent a hazard to the aquatic organisms. Subchronic assay with 17-alpha-ethinylestradiol (EE2) and in vitro essays with pharmaceuticals of environmental concern were conducted to examine the sensitivity of tissue acetylcholinesterase (AChE) and carboxylesterase (CbE) activities of Tinca tinca to them. Subchronic exposure to 17-alpha-EE2 caused significant effects on brain, liver, and muscle CbE, but no on AChE activities. Most of the pharmaceuticals tested in vitro were considered as weak inhibitors of tissular AChE activity. Depending on the tissues, some compounds were classified as moderate inhibitors of CbE activity while other were categorized as weak enzymatic inhibitors. An opposite trend was observed depending on the tissue, while brain and liver CbE activities were inhibited, the muscle CbE activity was induced. Changes experienced on enzymatic activities after exposure to pharmaceuticals might affect the physiological functions in which these enzymes are involved. In vitro exposure to 17-alpha-EE2 in tench could be an informative, but not a surrogate model to know the effect of this synthetic estrogen on AChE and CbE activities.


Assuntos
Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Fígado/efeitos dos fármacos , Fígado/enzimologia , Cyprinidae , Acetilcolinesterase/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Inibidores da Colinesterase/toxicidade , Músculos/efeitos dos fármacos , Músculos/enzimologia , Carboxilesterase/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Colinesterases/metabolismo
2.
Rev Argent Microbiol ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38871623

RESUMO

The aim of this study was to detect vector-borne pathogens (Anaplasmataceae family, Rickettsia genus, and Bartonella genus) in bats from Misiones (Argentina). Thirty-three specimens were captured over 8 days using mist nets. Twenty (60.6%) blood samples were positive (11/13 Artibeus lituratus, 4/10 Desmodus rotundus, 4/8 Carollia perspicillata, and 1/2 Myotis nigricans) by PCR for the gltA gene fragment of Bartonella. All samples were negative by PCR for the Anaplasmataceae family and Rickettsia genus. The phylogenetic analysis showed seven Bartonella genotypes. The three genotypes obtained from A. lituratus, 2 from C. perspicillata, and 1 from D. rotundus were related to Bartonella spp. from New World bats, while the sequence obtained from M. nigricans was related to Old World bats. We identified a considerable diversity of Bartonella genotypes in a small number of bats, thus further research is required to better understand the complex bat-pathogen interaction.

3.
J Phys Chem A ; 127(6): 1491-1498, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36749871

RESUMO

Gas-phase and aqueous oxidations of formic and oxalic acids with ozone and OH radicals have been thoroughly examined by DFT methods. Such acids are not only important feedstocks for the iterative construction of other organic compounds but also final products generated by mineralization and advanced oxidation of higher organics. Our computational simulation unravels both common and distinctive reaction channels, albeit consistent with known H atom abstraction pathways and formation of hydropolyoxide derivatives. Notably, reactions with neutral ozone and OH radical proceed through low-energy concerted mechanisms involving asynchronous transition structures. For formic acid, carbonylic H-abstraction appears to be more favorable than the dissociative abstraction of the acid proton. Formation of long oxygen chains does not cause a significant energy penalty and highly oxygenated products are stable enough, even if subsequent decomposition releases environmentally benign side substances like O2 and H2O.

4.
J Environ Manage ; 233: 513-522, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30594116

RESUMO

This work reports the combination of ozone and solar radiation as an advanced oxidation process to remove the herbicide tritosufuron (TSF) in water. Firstly, the recalcitrance of TSF has been assessed, obtaining an ozonation second order rate constant of 5-154 M-1 min-1 in the range of pH from 5 to 8; while the rate constant with HO was found to be (1.8-3.1)·109 M-1 s-1. Secondly, the simultaneous application of simulated solar radiation in between 300 and 800 nm and ozone resulted positive in the oxidation rate of TSF. Mineralization extent was also higher. Less effective oxidation was achieved after limiting the radiation to the range 360-800 nm or 390-800 nm; also completely inappropriate for mineralization. Thirdly, the detected transformation products (TPs) demonstrated the vulnerability of TSF molecule to be attacked by HO in the sulfonylurea bridge. The combination of ozone and radiation of 300-800 nm led to the most effective removal of the TPs. Finally, after the photolytic ozonation treatment toxicity was also evaluated in terms of phytotoxicity towards the germination and root elongation of Lactuca Sativa seeds, and toxicity by immobilization tests of Daphnia Magna.


Assuntos
Ozônio , Poluentes Químicos da Água , Animais , Hidrocarbonetos Fluorados , Oxirredução , Fotólise , Triazinas , Ureia/análogos & derivados
5.
Molecules ; 24(19)2019 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-31546708

RESUMO

The use of graphene-based materials as catalysts in both ozone and ozone/radiation processes is creating interest among researchers devoted to the study of advanced oxidation processes (AOPs) for the degradation of organic pollutants in water. In this review, detailed explanations of catalytic and photocatalytic ozonation processes mediated by graphene-based materials are presented, focusing on aspects related to the preparation and characterization of catalysts, the nature of the water pollutants treated, the type of reactors and radiation sources applied, the influence of the main operating variables, catalyst activity and stability, and kinetics and mechanisms.


Assuntos
Grafite/química , Ozônio/química , Poluentes Químicos da Água/química , Catálise , Oxirredução , Poluentes da Água/química , Purificação da Água/métodos
6.
Molecules ; 24(9)2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31058864

RESUMO

In this work, primidone, a high persistent pharmacological drug typically found in urban wastewaters, was degraded by different ozone combined AOPs using TiO2 P25 and commercial WO3 as photocatalyst. The comparison of processes, kinetics, nature of transformation products, and ecotoxicity of treated water samples, as well as the influence of the water matrix (ultrapure water or a secondary effluent), is presented and discussed. In presence of ozone, primidone is rapidly eliminated, with hydroxyl radicals being the main species involved. TiO2 was the most active catalyst regardless of the water matrix and the type of solar (global or visible) radiation applied. The synergy between ozone and photocatalysis (photocatalytic ozonation) for TOC removal was more evident at low O3 doses. In spite of having a lower band gap than TiO2 P25, WO3 did not bring any beneficial effects compared to TiO2 P25 regarding PRM and TOC removal. Based on the transformation products identified during ozonation and photocatalytic ozonation of primidone (hydroxyprimidone, phenyl-ethyl-malonamide, and 5-ethyldihydropirimidine-4,6(1H,5H)-dione), a degradation pathway is proposed. The application of the different processes resulted in an environmentally safe effluent for Daphnia magna.


Assuntos
Óxidos/química , Ozônio/química , Primidona/análise , Titânio/química , Tungstênio/química , Poluentes Químicos da Água/análise , Animais , Catálise , Daphnia/efeitos dos fármacos , Daphnia/crescimento & desenvolvimento , Radical Hidroxila/química , Cinética , Oxirredução , Processos Fotoquímicos , Luz Solar , Raios Ultravioleta , Água/química , Purificação da Água
7.
Molecules ; 22(7)2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28708117

RESUMO

An incipient advanced oxidation process, solar photocatalytic ozonation (SPO), is reviewed in this paper with the aim of clarifying the importance of this process as a more sustainable water technology to remove priority or emerging contaminants from water. The synergism between ozonation and photocatalytic oxidation is well known to increase the oxidation rate of water contaminants, but this has mainly been studied in photocatalytic ozonation systems with lamps of different radiation wavelength, especially of ultraviolet nature (UVC, UVB, UVA). Nowadays, process sustainability is critical in environmental technologies including water treatment and reuse; the application of SPO systems falls into this category, and contributes to saving energy and water. In this review, we summarized works published on photocatalytic ozonation where the radiation source is the Sun or simulated solar light, specifically, lamps emitting radiation to cover the UVA and visible light spectra. The main aspects of the review include photoreactors used and radiation sources applied, synthesis and characterization of catalysts applied, influence of main process variables (ozone, catalyst, and pollutant concentrations, light intensity), type of water, biodegradability and ecotoxicity, mechanism and kinetics, and finally catalyst activity and stability.


Assuntos
Ozônio/química , Luz Solar , Raios Ultravioleta , Poluentes Químicos da Água/química , Purificação da Água/métodos , Biodegradação Ambiental , Catálise , Cinética , Oxirredução , Águas Residuárias/química , Água
8.
Artigo em Inglês | MEDLINE | ID: mdl-25837558

RESUMO

A synthetic secondary effluent containing an aqueous mixture of emerging contaminants (ECs) has been treated by photocatalytic ozonation using Fe(3+) or Fe3O4 as catalysts and black light lamps as the radiation source. For comparative purposes, ECs have also been treated by ultraviolet radiation (UVA radiation, black light) and ozonation (pH 3 and 7). With the exception of UVA radiation, O3-based processes lead to the total removal of ECs in the mixture. The time taken to achieve complete degradation depends on the oxidation process applied. Ozonation at pH 3 is the most effective technique. The addition of iron based catalysts results in a slight inhibition of the parent compounds degradation rate. However, a positive effect is experienced when measuring the total organic carbon (TOC) and the chemical oxygen demand (COD) removals. Photocatalytic oxidation in the presence of Fe(3+) leads to 81% and 88% of TOC and COD elimination, respectively, compared to only 23% and 29% of TOC and COD removals achieved by single ozonation. The RCT concept has been used to predict the theoretical ECs profiles in the homogeneous photocatalytic oxidation process studied. Treated wastewater effluent was toxic to Daphnia magna when Fe(3+) was used in photocatalytic ozonation. In this case, toxicity was likely due to the ferryoxalate formed in the process. Single ozonation significantly reduced the toxicity of the treated wastewater.


Assuntos
Ferro/química , Ozônio/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes da Água/química , Animais , Catálise , Oxirredução , Raios Ultravioleta
9.
Rev Argent Microbiol ; 47(4): 312-6, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26627114

RESUMO

Our goal was to determine the presence of neutralizing antibodies against St. Louis encephalitis virus (SLEV) and West Nile virus (WNV) in sera of wild and domestic birds from Buenos Aires City, Argentina. From October 2012 to April 2013, 180 samples were collected and processed by the microneutralization technique. A 7.2% of the sampled birds were seropositive for SLEV, while no seropositive birds for WNV were detected.


Assuntos
Anticorpos Antivirais/sangue , Aves/sangue , Vírus da Encefalite de St. Louis/imunologia , Vírus do Nilo Ocidental/imunologia , Animais , Argentina , Saúde da População Urbana
10.
Artigo em Inglês | MEDLINE | ID: mdl-24798900

RESUMO

Sequential treatments consisting in a chemical process followed by a conventional biological treatment, have been applied to remove mixtures of nine contaminants of pharmaceutical type spiked in a primary sedimentation effluent of a municipal wastewater. Combinations of ozone, UVA black light (BL) and Fe(III) or Fe3O4 catalysts constituted the chemical systems. Regardless of the Advanced Oxidation Process (AOP), the removal of pharmaceutical compounds was achieved in 1 h of reaction, while total organic carbon (TOC) only diminished between 3.4 and 6%. Among selected ozonation systems to be implemented before the biological treatment, the application of ozone alone in the pre-treatment stage is recommended due to the increase of the biodegradability observed. The application of ozone followed by the conventional biological treatment leads high TOC and COD removal rates, 60 and 61%, respectively, and allows the subsequent biological treatment works with shorter hydraulic residence time (HRT). Moreover, the influence of the application of AOPs before and after a conventional biological process was compared, concluding that the decision to take depends on the characterization of the initial wastewater with pharmaceutical compounds.


Assuntos
Óxido Ferroso-Férrico/química , Ferro/química , Ozônio/química , Preparações Farmacêuticas/química , Poluentes Químicos da Água/química , Catálise , Cidades , Oxirredução , Preparações Farmacêuticas/metabolismo , Esgotos/microbiologia , Raios Ultravioleta , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-24345239

RESUMO

Removal of nine pharmaceutical compounds--acetaminophen (AAF), antipyrine (ANT), caffeine (CAF), carbamazepine (CRB), diclofenac (DCF), hydrochlorothiazide (HCT), ketorolac (KET), metoprolol (MET) and sulfamethoxazole (SMX)-spiked in a primary sedimentation effluent of a municipal wastewater has been studied with sequential aerobic biological and ozone advanced oxidation systems. Combinations of ozone, UVA black light and Fe(III) or Fe3O4 constituted the chemical systems. During the biological treatment (hydraulic residence time, HRT = 24 h), only AAF and CAF were completely eliminated, MET, SMX and HCT reached partial removal rates and the rest of compounds were completely refractory. With any ozone advanced oxidation process applied, the remaining pharmaceuticals disappear in less than 10 min. Fe3O4 or Fe(III) photocatalytic ozonation leads to 35% mineralization compared to 13% reached during ozonation alone after about 30-min reaction. Also, biodegradability of the treated wastewater increased 50% in the biological process plus another 150% after the ozonation processes. Both untreated and treated wastewater was non-toxic for Daphnia magna (D. magna) except when Fe(III) was used in photocatalytic ozonation. In this case, toxicity was likely due to the ferryoxalate formed in the process. Kinetic information on ozone processes reveals that pharmaceuticals at concentrations they have in urban wastewater are mainly removed through free radical oxidation.


Assuntos
Ozônio/química , Preparações Farmacêuticas/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/toxicidade , Poluentes Químicos da Água/química , Animais , Biodegradação Ambiental , Carbono/química , Carbono/metabolismo , Daphnia/efeitos dos fármacos , Ferro/química , Cinética , Oxirredução , Testes de Toxicidade , Águas Residuárias/química
12.
Medicina (B Aires) ; 74(6): 433-6, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-25555001

RESUMO

During March 2013 a population of eared doves (Zenaida auriculata) was established in the center of City of Buenos Aires. Considering the role of these birds as host competent for Saint Louis encephalitis virus (SLEV), a CDC light trap was put in place to perform entomologic surveillance. During this month 5 pools of mosquitoes (n = 48) were collected and taxonomically determined. Three of them were classified as Culex pipiens (n = 10) and the other two were Culex spp. (n = 38). In this case, the mosquitoes species could not be determined due to that individuals were damaged. One of the Culex spp. pool was found to be positive for Saint Louis encephalitis virus by molecular techniques. This was then sequenced and classified as genotype III.


Assuntos
Columbidae/virologia , Culex/virologia , Vírus da Encefalite de St. Louis/isolamento & purificação , Técnicas de Diagnóstico Molecular , Animais , Argentina , Reservatórios de Doenças/virologia , Vetores de Doenças/classificação , Vírus da Encefalite de St. Louis/classificação , Encefalite de St. Louis/transmissão , Genótipo , População Urbana
13.
Rev Chilena Infectol ; 31(5): 563-8, 2014 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-25491455

RESUMO

BACKGROUND: Rickettsioses, ehrlichioses and anaplasmoses are caused by Gram negative obligate intracellular bacteria and transmitted mainly by arthropods. AIM: To detect and perform the molecular characterization of these pathogens in ticks and domestic dogs in Bahia Blanca City (Buenos Aires, Argentina). METHODS: Fifty six blood samples from dogs and 82 ticks (75 Rhipicephalus sanguineus and 7 Amblyomma tigrinum) were studied. The samples were analyzed by PCR for Rickettsia (intergenic space 23S-5S rRNA), Ehrlichia/Anaplasma (16S rRNA), and Anaplasma platys (16S rRNA). RESULTS: 12% of R. sanguineus resulted positive for Rickettsia, identified by sequencing as Rickettsia massiliae; and 37.5% of the canine blood samples analyzed were positive for A. platys. Molecular characterization was also performed by amplification of the fragment of the citrate synthase gene (gltA) (Rickettsia genus) and the groESL gene (A. platys). Phylogenetic trees were constructed using the neighbor-joining method. These trees revealed that sequences obtained are similar to those from other geographical regions. CONCLUSION: The results indicate the presence of R. massiliae in R. sanguineus ticks for the second time in an urban area of South America and A. platys infection in dogs, being the southernmost region of Argentina where it has been notified.


Assuntos
Anaplasma/genética , Anaplasmose/epidemiologia , Doenças do Cão/epidemiologia , Rhipicephalus sanguineus/microbiologia , Infecções por Rickettsia/veterinária , Rickettsia/genética , Infestações por Carrapato/veterinária , Animais , Argentina/epidemiologia , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Filogenia , Infecções por Rickettsia/epidemiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/microbiologia
14.
J Environ Manage ; 127: 114-24, 2013 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-23685272

RESUMO

Aqueous solutions of four pharmaceutical compounds, belonging to the group of emergent contaminants of water: atenolol (ATL), hydrochlorothiazide (HCT), ofloxacin (OFX) and trimethoprim (TMP), have been treated with different oxidation systems, mainly, photocatalytic oxidation, ozonation and photocatalytic ozonation. TiO2 has been used as semiconductor for photocatalytic reactions both in the presence of air, oxygen or ozone-oxygen gas mixtures. Black light lamps mainly emitting at 365 nm were the source of radiation. In all cases, the influence of some variables (concentrations of semiconductor, ozone gas and pharmaceuticals and pH) on the removal of pharmaceuticals, total polyphenol content (TPC) and total organic carbon (TOC) was investigated. A discussion on the possible routes of pharmaceutical and intermediates (as TPC and TOC) elimination has been developed. Thus, OFX TiO2/UVA degradation mechanism seems to develop through the participation of non-hydroxyl free radical species. Furthermore, the presence of OFX inhibits the formation of hydroxyl radicals in the photocatalytic process. The most effective processes were those involving ozone that lead to complete disappearance of parent compounds in less than 30 min for initial pharmaceutical concentrations lower than 2.5 mg L(-1). In the ozonation systems, regardless of the pH and the presence of TiO2, pharmaceuticals are degraded through their direct reaction with ozone. Photocatalytic ozonation was the most efficient process for TPC and TOC removals (≥ 80% and ≥60% elimination after 2 h of treatment, respectively) as well as in terms of the ozone consumption efficiency (1, 5.5 and 4 mol of ozone consumed per mol of TOC mineralized, at pH 4, 7 and 9, respectively). Weakly acid conditions (pH 4) resulted to be the most convenient ones for TPC and TOC removal by photocatalytic ozonation. This was likely due to formation of hydroxyl radicals through the ozonide generated at these conditions.


Assuntos
Atenolol/química , Hidroclorotiazida/química , Ofloxacino/química , Ozônio/química , Trimetoprima/química , Poluentes Químicos da Água/química , Adsorção , Atenolol/análise , Recuperação e Remediação Ambiental/métodos , Hidroclorotiazida/análise , Concentração de Íons de Hidrogênio , Ofloxacino/análise , Oxirredução , Oxigênio/química , Processos Fotoquímicos , Semicondutores , Titânio/química , Trimetoprima/análise , Raios Ultravioleta , Poluentes Químicos da Água/análise
15.
J Environ Manage ; 100: 10-5, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22343613

RESUMO

A mixture of nine pharmaceuticals has been treated by means of the systems: UV-B(313 nm), O(3), UV-B(313 nm) + TiO(2), O(3) + UV-B(313 nm), and O(3) + UV-B(313 nm)+TiO(2). Simple photolytic or ozonation processes lead to a deficient total organic carbon (TOC) elimination after 120 min of exposure (25 and 30% conversions, respectively). Addition of a photocatalyst such as titanium dioxide significantly enhanced the mineralization degree, a 60% TOC conversion was obtained. A TiO(2) load optimum around 0.25 g L(-1) was observed. No loss in photoactivity was experienced after 2 reuses. Due to ozone photodegradation, the combination of ozone and radiation increased the generation of hydroxyl radicals. As a consequence, TOC removal was increased to a value in the proximity of 85%. The most complex system, O(3) + UV-B(313 nm) + TiO(2), achieved the highest TOC abatement (95%). Use of ozone in photocatalytic processes involves an increase in hydroxyl radical generation.


Assuntos
Ozônio/química , Fotoquímica/métodos , Purificação da Água/métodos , Catálise/efeitos da radiação , Titânio/química , Raios Ultravioleta , Poluentes Químicos da Água/química
16.
Diseases ; 10(1)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35323184

RESUMO

Rabies is a zoonotic disease caused by the rabies virus (RABV) that causes fatal encephalitis in mammals. Bats can transmit the disease to urban canines and felines, which rarely infect humans, establishing a secondary link. The last case of human rabies in Argentina was transmitted by a dog in 2008. We present the first case of human rabies originating from an insectivorous bat, Tadarida brasiliensis, transmitted by a feral cat in Buenos Aires province, Argentina.

17.
Water Res ; 206: 117727, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624657

RESUMO

Numerous studies report on the synergy between ozonation and photocatalytic oxidation (TiO2/UVA), which could open the way to the application of photocatalytic ozonation (PCOz) in water treatment. With the aim of establishing the existence of this synergy and its origin, in this work, using TiO2 P25, 365 nm UVA LEDs and ozone transferred doses up to 5 mg (mg DOC0)-1 (DOC0 7 - 10 mg L-1), a systematic study has been carried out featuring the effect of pH, alkalinity and water matrix in each of the systems involved in PCOz, with special attention to the role of organics adsorption onto TiO2. In ultrapure water, an increase in pH and carbonates content exerted a slight negative effect on the photocatalytic degradation of primidone (low adsorption onto TiO2 and mainly abated by free HO•), this effect being higher on its mineralization. The negative effect of pH and alkalinity was much stronger for oxalic acid (high tendency to adsorb and mainly oxidized by positive holes). Accordingly, the results obtained at pH < pHpzc (point of zero charge of the catalyst) in ultrapure water cannot at all be extrapolated to secondary effluents, since their composition negatively affects the photocatalytic performance. At the experimental conditions applied, only for the secondary effluent a synergy between O3/UVA and TiO2/UVA systems was observed. This synergy would be related, on the one hand, to the generation, from the matrix itself, of reactive entities or intermediates that promote the decomposition of ozone into HO•; and, on the other hand, to an increase in catalyst activity as the matrix UVA absorption decreases, rather than from direct interactions between both systems. Despite de above, ozone requirement to achieve a significant reduction of DOC is high and would only be an interesting strategy for the elimination of ozone-refractory micropollutants.


Assuntos
Ozônio , Poluentes Químicos da Água , Purificação da Água , Catálise , Oxirredução , Titânio , Poluentes Químicos da Água/análise
18.
Viruses ; 13(12)2021 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-34960753

RESUMO

The rabies virus (RABV) is characterized by a history dominated by host shifts within and among bats and carnivores. One of the main outcomes of long-term RABV maintenance in dogs was the establishment of variants in a wide variety of mesocarnivores. In this study, we present the most comprehensive phylogenetic and phylogeographic analysis, contributing to a better understanding of the origins, diversification, and the role of different host species in the evolution and diffusion of a dog-related variant endemic of South America. A total of 237 complete Nucleoprotein gene sequences were studied, corresponding to wild and domestic species, performing selection analyses, ancestral states reconstructions, and recombination analyses. This variant originated in Brazil and disseminated through Argentina and Paraguay, where a previously unknown lineage was found. A single host shift was identified in the phylogeny, from dog to the crab-eating fox (Cerdocyon thous) in the Northeast of Brazil. Although this process occurred in a background of purifying selection, there is evidence of adaptive evolution -or selection of sub-consensus sequences- in internal branches after the host shift. The interaction of domestic and wild cycles persisted after host switching, as revealed by spillover and putative recombination events.


Assuntos
Vírus da Raiva/genética , Vírus da Raiva/isolamento & purificação , Raiva/veterinária , Animais , Animais Domésticos/virologia , Animais Selvagens/virologia , Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Cães , Evolução Molecular , Raposas/virologia , Nucleoproteínas/genética , Filogenia , Raiva/epidemiologia , Raiva/virologia , Vírus da Raiva/classificação , Recombinação Genética , América do Sul/epidemiologia
19.
Viruses ; 13(1)2020 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375530

RESUMO

In rabies diagnosis, it is essential to count on a rapid test to give a quick response. The combined sensitivity and robustness of the TaqMan RT-PCR assays (qRT-PCR) have made these methods a valuable alternative for rabies virus (RABV) detection. We conducted a study to compare the applicability of two widely used qRT-PCR assays targeting the nucleoprotein gene (LysGT1 assay) and leader sequences (LN34 qRT-PCR assay) of RABV genomes, in all variants circulating in Argentina. A total of 44 samples obtained from bats, dogs, cattle, and horses, that were previously tested for rabies by FAT and conventional RT-PCR, were used in the study. All variants were successfully detected by the pan-lyssavirus LN34 qRT-PCR assay. The LysGT1 assay failed to detect three bat-related variants. We further sequenced the region targeted by LysGT1 and demonstrated that the presence of three or more mismatches with respect to the primers and probe sequences precludes viral detection. We conclude that the LysGT1 assay is prone to yield variant-dependent false-negative test results, and in consequence, the LN34 assay would ensure more effective detection of RABV in Argentina.


Assuntos
Variação Genética , Vírus da Raiva/genética , Raiva/diagnóstico , Raiva/virologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sequência de Aminoácidos , Animais , Argentina/epidemiologia , Bovinos , Quirópteros , Geografia Médica , Cavalos , Humanos , Nucleoproteínas/genética , Filogenia , Filogeografia , RNA Viral , Raiva/epidemiologia , Vírus da Raiva/classificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
20.
PLoS One ; 15(12): e0244750, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382800

RESUMO

Bats are among the most diverse, widespread, and abundant mammals. In Argentina, 67 species of bats have been recorded, belonging to 5 families and 29 genera. These high levels of biodiversity are likely to complicate identification at fieldwork, especially between closely related species, where external morphology-based approaches are the only immediate means for a priori species assignment. The use of molecular markers can enhance species identification, and acquires particular relevance in capture-release studies. In this study, we discuss the extent of the use of the mitochondrial cytochrome b gene for species identification, comparing external morphology identification with a molecular phylogenetic classification based on this marker, under the light of current bat systematics. We analyzed 33 samples collected in an eco-epidemiological survey in the province of Santa Fe (Argentina). We further sequenced 27 museum vouchers to test the accuracy of cytochrome b -based phylogenies in taxonomic identification of bats occurring in the Pampean/Chacoan regions of Argentina. The cytochrome b gene was successfully amplified in all Molossid and Vespertilionid species except for Eptesicus, for which we designed a new reverse primer. The resulting Bayesian phylogeny was congruent with current systematics. Cytochrome b proved useful for species-level delimitation in non-conflicting genera (Eumops, Dasypterus, Molossops) and has infrageneric resolution in more complex lineages (Eptesicus, Myotis, Molossus). We discuss four sources of incongruence that may act separately or in combination: 1) molecular processes, 2) biology, 3) limitations in identification, and 4) errors in the current taxonomy. The present study confirms the general applicability of cytochrome b -based phylogenies in eco-epidemiological studies, but its resolution and reliability depend mainly, but not solely, on the level of genetic differentiation within each bat genus.


Assuntos
Quirópteros/genética , Citocromos b/genética , DNA Mitocondrial/genética , Variação Genética , Animais , Argentina , Filogenia
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