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1.
Am J Biol Anthropol ; : e25013, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39139025

RESUMO

OBJECTIVES: When the production of antipredator behaviors is costly, prey is expected to stop displaying such behaviors and lose the ability to recognize extirpated predators. However, the loss or maintenance of predator recognition abilities is conditional on the eco-evolutionary context of prey. Here, we examined the behavioral responses of naïve and experienced mantled howler monkeys (Alouatta palliata) to simulated acoustic cues from natural predators. METHODS: We studied experienced individuals in the Uxpanapa Valley and naïve individuals in Los Tuxtlas (Veracruz, México). Jaguars (Panthera onca) and harpy eagles (Harpia harpyja), the main predators of howler monkeys, are extant in the Uxpanapa Valley but have been extirpated in Los Tuxtlas for approximately 70 and 45 years, respectively. We exposed six naïve and six experienced groups to playbacks of acoustic stimuli from the two predators and a non-predator control species (plain chachalacas, Ortalis vetula), and recorded the latency, frequency, and duration of antipredation behaviors (n = 127 trials). RESULTS: In contrast with experienced mantled howler monkeys, naïve subjects did not respond to trials from harpy eagles. However, response patterns were generally similar between naïve and experienced individuals when exposed to jaguar stimuli. DISCUSSION: Our findings suggest that naïve mantled howler monkeys do not recognize harpy eagle calls, but they respond to jaguar calls in a manner consistent with experienced individuals. These results illustrate how different mechanisms for the recognition of extirpated predators operate within a single species according to evolutionary and ecological experience.

2.
Chaos ; 34(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38885072

RESUMO

The equatorial region of the Earth's atmosphere serves as both a significant locus for phenomena, including the Madden-Julian Oscillation (MJO), and a source of formidable complexity. This complexity arises from the intricate interplay between nonlinearity and thermodynamic processes, particularly those involving moisture. In this study, we employ a normal mode decomposition of atmospheric reanalysis ERA-5 datasets to investigate the influence of nonlinearity and moisture on amplitude growth, propagation speed, and mode coupling associated with equatorially trapped waves. We focus our analysis on global-scale baroclinic Kelvin and Rossby waves, recognized as crucial components contributing to the variability of the MJO. We examine the dependence of wave amplitudes on the background moisture field in the equatorial region, as measured by total column water vapor. Our analysis demonstrates the crucial role of moisture in exciting these waves. We further investigate the dependence of the propagation speed of the waves on their amplitudes and the background moisture field. Our analysis reveals a robust correlation between the phase speed of the normal modes and their corresponding amplitude, whereas a weaker correlation is found between the eigenmodes' phase speed and the moisture field. Hence, our findings suggest that moisture plays a role in exciting the global-scale Rossby-Kelvin structure of the MJO. In this context, the propagation speed of the eigenmodes is mainly influenced by their amplitudes, underscoring the significant role of nonlinearity in wave propagation.

3.
Cells ; 13(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38534317

RESUMO

Mitochondria provide energy for all cellular processes, including reactions associated with cell cycle progression, DNA damage repair, and cilia formation. Moreover, mitochondria participate in cell fate decisions between death and survival. Nek family members have already been implicated in DNA damage response, cilia formation, cell death, and cell cycle control. Here, we discuss the role of several Nek family members, namely Nek1, Nek4, Nek5, Nek6, and Nek10, which are not exclusively dedicated to cell cycle-related functions, in controlling mitochondrial functions. Specifically, we review the function of these Neks in mitochondrial respiration and dynamics, mtDNA maintenance, stress response, and cell death. Finally, we discuss the interplay of other cell cycle kinases in mitochondrial function and vice versa. Nek1, Nek5, and Nek6 are connected to the stress response, including ROS control, mtDNA repair, autophagy, and apoptosis. Nek4, in turn, seems to be related to mitochondrial dynamics, while Nek10 is involved with mitochondrial metabolism. Here, we propose that the participation of Neks in mitochondrial roles is a new functional axis for the Nek family.


Assuntos
Mitocôndrias , Proteínas Serina-Treonina Quinases , Quinases Relacionadas a NIMA/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Mitocôndrias/metabolismo , Homeostase , DNA Mitocondrial
4.
Proc Natl Acad Sci U S A ; 121(6): e2305944121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38252845

RESUMO

Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas' effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demographic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a "winner and loser" species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.


Assuntos
Biodiversidade , Ecossistema , Humanos , Animais , Agricultura , Animais Selvagens , Mudança Climática
5.
Am J Primatol ; 86(4): e23598, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38258612

RESUMO

We report on an analytical and biological validation of a commercial cortisol enzyme immunoassay (EIA) to measure glucocorticoids (GC) in feces of Geoffroy's spider monkeys (Ateles geoffroyi). Validation of endocrinological methods for each sample matrix and study species is crucial to establish that the methods produce reliable results. For the analytical validation of the EIA, we assessed parallelism, accuracy, and precision. We carried out a biological validation based on three well-studied GC patterns with the following predictions: (1) increased fecal GC metabolite (fGCM) concentrations after veterinary intervention; (2) increased fGCM concentrations during early morning hours; and (3) higher fGCM concentrations during gestation than in other female reproductive states. For the first prediction, we sampled feces of two zoo-housed females 2 days before, the day of, and 2 days after a veterinary intervention. For the second prediction, we analyzed 284 fecal samples collected from 12 wild males using a linear mixed model (LMM). For the third prediction, we analyzed 269 fecal samples of eight wild females using an LMM. Analytical validation revealed that the EIA showed parallelism, was accurate, and precise within each assay. However, there was elevated variation in between-assay precision. The biological validation supported all predictions: (1) the two zoo-housed females showed a substantial increase in fGCM concentrations 2.5 and 11 h after veterinary intervention; (2) there was a negative effect of sample collection time on fGCM concentrations (i.e., higher concentrations during early morning); (3) gestating females had significantly higher fGCM concentrations than lactating females. Thus, we analytically validated the commercial EIA and, despite between-assay variation, we were able to find three biologically relevant GC signals in captive and wild settings, and in males and females. We are therefore confident that the method can be used to noninvasively address behavioral endocrinology questions in Geoffroy's spider monkeys.


Assuntos
Ateles geoffroyi , Glucocorticoides , Masculino , Animais , Feminino , Glucocorticoides/metabolismo , Lactação , Hidrocortisona , Fezes
7.
Am J Primatol ; 86(1): e23568, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37850516

RESUMO

Anthropogenic noise is a major global pollutant but its effects on primates are poorly understood, limiting our ability to develop mitigation actions that favor their welfare and conservation. In this study, we used an experimental approach to determine the impact of variation in noise intensity on mantled howler monkeys (Alouatta palliata). We conducted the study at Los Tuxtlas (México), where we studied the physiological stress (proxied via fecal glucocorticoid metabolites, fGCM) and behavioral responses of 16 males. We played back chainsaw noise at two intensities (40 and 80 dB) and used days in which groups were not exposed to noise as matched controls. With increased noise intensity fGCM increased, vigilance and vocalizations were longer, and vigilance, vocalizations, and flight occurred quicker. Physiological and behavioral responses occurred even after low-intensity noise playbacks (i.e., 40 dB). Therefore, noise intensity is a significant factor explaining the responses of mantled howler monkeys to anthropogenic noise. These results imply that management actions aimed at eradicating anthropogenic noise are required for the conservation and welfare of mantled howler monkeys at Los Tuxtlas.


Assuntos
Alouatta , Glucocorticoides , Masculino , Animais , Glucocorticoides/metabolismo , Comportamento Animal/fisiologia , Alouatta/fisiologia , Primatas , México
8.
Talanta ; 269: 125482, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38042146

RESUMO

Attenuated Total Reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy is an emerging technology in the medical field. Blood D-dimer was initially studied as a marker of the activation of coagulation and fibrinolysis. It is mainly used as a potential diagnosis screening test for pulmonary embolism or deep vein thrombosis but was recently associated with COVID-19 severity. This study aimed to evaluate the use of ATR-FTIR spectroscopy with machine learning to classify plasma D-dimer concentrations. The plasma ATR-FTIR spectra from 100 patients were studied through principal component analysis (PCA) and two supervised approaches: genetic algorithm with linear discriminant analysis (GA-LDA) and partial least squares with linear discriminant (PLS-DA). The spectra were truncated to the fingerprint region (1800-1000 cm-1). The GA-LDA method effectively classified patients according to D-dimer cutoff (≤0.5 µg/mL and >0.5 µg/mL) with 87.5 % specificity and 100 % sensitivity on the training set, and 85.7 % specificity, and 95.6 % sensitivity on the test set. Thus, we demonstrate that ATR-FTIR spectroscopy might be an important additional tool for classifying patients according to D-dimer values. ATR-FTIR spectral analyses associated with clinical evidence can contribute to a faster and more accurate medical diagnosis, reduce patient morbidity, and save resources and demand for professionals.


Assuntos
Espectroscopia de Infravermelho com Transformada de Fourier , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise de Fourier , Análise Discriminante , Análise de Componente Principal , Proteínas Mutadas de Ataxia Telangiectasia
9.
Am J Biol Anthropol ; 182(1): 59-68, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37417878

RESUMO

OBJECTIVES: Long-distance vocalizations are used by primates in a variety of contexts and may have different functions. The long-distance vocalizations of howler monkeys (Alouatta spp.) underlie the spatial regulation of neighboring groups and could be associated with the defense of food resources. Here, we test the hypothesis that the behavioral responses of mantled howler monkeys (A. palliata) to neighbor long-distance vocalizations are influenced by the potential for range defensibility while accounting for location within the home range and food availability. METHODS: We studied two groups for 13 months and a total of 888 h at La Flor de Catemaco (Mexico). Group 1 had a 92-ha home range and Group 2 had a 24-ha home range. We recorded vocalizations (N = 178 calls) and movements (N = 74 movements) of focal groups following long-distance vocalizations produced by their neighbors. RESULTS: Movement responses, but not vocal responses, were predicted by range defensibility, location, and food availability. As predicted, the group living in the smaller and more defendable range showed stronger movement responses than the group in the larger home range. These movement responses had a shorter latency and longer duration in more valuable spatial and temporal contexts (i.e., the core area and during periods of low food availability). CONCLUSIONS: These results suggest that the tradeoff between the costs and benefits of range defense varies according to the interactions between home range size and both the spatial (core areas) and temporal (food availability) abundance of resources. Thus, the responses of mantled howler monkeys to neighbor long-distance vocalizations could be related to home range defensibility.


Assuntos
Alouatta , Comportamento Social , Animais , Alouatta/fisiologia , Alimentos , Movimento
10.
Zootaxa ; 5285(2): 325-336, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37518703

RESUMO

We describe a new species of the genus Endecous Saussure (1878), recorded at the Dente de Cão and Urubu Rei caves, which are located in the Bodoquena municipality, state of Mato Grosso do Sul, Brazil. Species of Endecous are the most common of crickets in Brazilian hypogean environments. Endecous comprises 24 species described and is widely distributed throughout South America, occurring also in Argentina, Bolivia and Uruguay. We also present a brief discussion about the presence of the genus in subterranean environments and a distribution map of Endecous troglobitic species through the regions of the Brazilian karst.


Assuntos
Críquete , Gryllidae , Ortópteros , Animais , Brasil , Cavernas , Escuridão
11.
Sci Total Environ ; 888: 163439, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37196956

RESUMO

Recently, extreme wildfires have damaged important ecosystems worldwide and have affected urban areas miles away due to long-range transport of smoke plumes. We performed a comprehensive analysis to clarify how smoke plumes from Pantanal and Amazon forests wildfires and sugarcane harvest burning also from interior of the state of São Paulo (ISSP) were transported and injected into the atmosphere of the Metropolitan Area of São Paulo (MASP), where they worsened air quality and increased greenhouse gas (GHG) levels. To classify event days, multiple biomass burning fingerprints as carbon isotopes, Lidar ratio and specific compounds ratios were combined with back trajectories modeling. During smoke plume event days in the MASP fine particulate matter concentrations exceeded the WHO standard (>25 µg m-3), at 99 % of the air quality monitoring stations, and peak CO2 excess were 100 % to 1178 % higher than non-event days. We demonstrated how external pollution events such as wildfires pose an additional challenge for cities, regarding public health threats associated to air quality, and reinforces the importance of GHG monitoring networks to track local and remote GHG emissions and sources in urban areas.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Incêndios , Saccharum , Incêndios Florestais , Poluentes Atmosféricos/análise , Brasil , Ecossistema , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Poluição do Ar/análise , Material Particulado/análise , Fumaça/análise , Florestas , Monitoramento Ambiental
12.
Sci Total Environ ; 882: 163585, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37088396

RESUMO

Non-lethal impacts of dogs on primates have seldom been assessed. We used an experimental approach to determine if mantled howler monkeys (Alouatta palliata) perceive dog barks as an aversive stimulus and thus display physiological and behavioral responses toward simulated barks. For one year (1754 h of observations) we studied 16 adult males belonging to five groups in Los Tuxtlas (Mexico), and recorded the occurrence of naturally occurring dog barks, their sound pressure level (SPL), and the behavioral responses of howler monkeys to barks. We then exposed males to bark playbacks at two SPL treatments, 40 and 80 dB in a total of 50 experiments. We assayed glucocorticoid metabolite concentrations in fecal samples (fGCM) as a marker of the physiological stress response of males. We also recorded the duration of vigilance, vocalizations, and flight in relation to playbacks. Naturally occurring barks were frequent and usually elicited behavioral responses by males. fGCM concentrations increased after bark playbacks and with stimuli intensity. Time spent vigilant increased following playbacks independently of stimuli intensity but both vocalizations and flight were linked to stimuli intensity: vocalizations were the longest after barks played-back at 80 dB, but males spent more time fleeing in response to 40 dB bark playbacks. These results provide evidence that dog barks are pervasive in the habitat of mantled howler monkeys living at Los Tuxtlas and disturb males, both physiologically and behaviorally. Although the potential costs of physiological and behavioral responses could not be determined, there is sufficient evidence to assume that they do have negative impacts on individuals. Therefore, our study provides avenues for future research on dog-wildlife interactions and valuable information for the design of conservation actions aimed at mitigating the impact of dogs on mantled howler monkeys.


Assuntos
Alouatta , Ecossistema , Masculino , Cães , Animais , Primatas , Glucocorticoides , Alouatta/metabolismo , Estresse Fisiológico , México
13.
Restor Dent Endod ; 48(1): e4, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36875808

RESUMO

Objectives: This study aimed to compare the torsional and cyclic fatigue resistance of ProGlider (PG), WaveOne Gold Glider (WGG), and TruNatomy Glider (TNG). Materials and Methods: A total of 15 instruments of each glide path system (n = 15) were used for each test. A custom-made device simulating an angle of 90° and a radius of 5 millimeters was used to assess cyclic fatigue resistance, with calculation of number of cycles to failure. Torsional fatigue resistance was assessed by maximum torque and angle of rotation. Fractured instruments were examined by scanning electron microscopy (SEM). Data were analyzed with Shapiro-Wilk and Kruskal-Wallis tests, and the significance level was set at 5%. Results: The WGG group showed greater cyclic fatigue resistance than the PG and TNG groups (p < 0.05). In the torsional fatigue test, the TNG group showed a higher angle of rotation, followed by the PG and WGG groups (p < 0.05). The TNG group was superior to the PG group in torsional resistance (p < 0.05). SEM analysis revealed ductile morphology, typical of the 2 fracture modes: cyclic fatigue and torsional fatigue. Conclusions: Reciprocating WGG instruments showed greater cyclic fatigue resistance, while TNG instruments were better in torsional fatigue resistance. The significance of these findings lies in the identification of the instruments' clinical applicability to guide the choice of the most appropriate instrument and enable the clinician to provide a more predictable glide path preparation.

14.
J Morphol ; 284(5): e21582, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36964924

RESUMO

Andean Toads of the genus Osornophryne are suspected to have direct development on the basis of clutch and egg features. In this work, we describe the morphology of Osornophryne occidentalis embryos from a nest collected in the field. Several traits are similar to those reported in brachycephaloid Eleutherodactylus coqui and other direct-developing lineages. These include the pattern of formation of the body wall and the absence of oral and buccopharyngeal structures. Other features indicate the retention of ancestral larval characters. The development of forelimbs occurs in part within the operculum as in species with biphasic ontogeny; this has been reported in other direct-developing species, and is similar to what is described in African viviparous bufonids. This salient feature, along with the long, low-finned tail and the long and folded intestine early differentiated, gives these embryos a rather tadpole-like appearance. Our data confirm that development in O. occidentalis occurs within terrestrial eggs until advanced stages, and this would satisfy current definitions of direct development. At the same time, morphological differences regarding other species with comparable breeding reinforce interpretations about the wide anatomical and ontogenetic variations associated with endotrophic nutrition.


Assuntos
Bufonidae , Animais , Larva
15.
Primates ; 64(1): 143-152, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36346535

RESUMO

Translocations usually aim at maintaining and enhancing wild populations. Thus, the long-term monitoring of translocated individuals is critical for assessing translocation success. In this study, we report the demographic and life-history parameters of mantled howler monkeys that were translocated to La Flor de Catemaco (Los Tuxtlas, Mexico) to determine the success of the translocation process. Nine individuals belonging to two social groups living in areas that were going to be destroyed were released into La Flor de Catemaco between 2002 and 2004. Before 2022 there were no resident monkeys at the site. From January 2012 to December 2021, we recorded births, deaths, migrations, and group formation (1535 sampling days). The population grew until reaching 35 mantled howler monkeys. Two new groups including both individuals born at the site and migrants were founded. Mean ± SD group size was 8.1 ± 1.1 individuals. We recorded 42 births and 14 deaths, mostly of young infants (< 6 months of age). We recorded emigrations and immigrations of adult and immature individuals as well as several instances of individuals that remained and reproduced in their natal groups. Mean female age at first birth was 57.8 ± 18.5 months, interbirth intervals were 23.3 ± 11.3 months, and birth rates were 0.5 ± 0.2 births per female per year. The growth and persistence of the groups at the site, as well as similarity in demographic and life-history parameters between this and unmanaged populations, suggest that mantled howler monkeys living at La Flor de Catemaco represent a stable population and thus that this was a successful translocation.


Assuntos
Alouatta , Gravidez , Feminino , Animais , Parto , Dinâmica Populacional , México
16.
Rev. bras. entomol ; Rev. bras. entomol;67(2): e20230005, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1449672

RESUMO

ABSTRACT Pair-formation, courtship, copulatory, and post-copulatory behaviors of Eidmanacris meridionalis Desutter-Grandcolas, 1995, were described under laboratory conditions and compared with congeneric species and other Phalangopsidae crickets whose mating behavior has been previously studied. Field observations for the species are also reported. Mating behaviors were observed in E. meridionalis couples: they first remained motionless, and then began walking through the arena screening the substrate. Mating behavior started with antennal contact, followed by males positioning themselves in front of females, that, when receptive, mounted on the males back and started feeding on metanotum secretions of the males. Copulation (female-above-male position) started with the engaging of copulatory structures and stopped with couple detachment. The end-to-end position was observed once, right after couple detachment. Males always remained with the spermatophore, which was eaten after removal or, alternatively, left in the substrate. The main differences in mating behavior of Eidmanacris species regard the mating position and the duration of the reproductive stages, suggesting that other reproductive repertoires can be observed in the genus since 27 species have not yet been studied in regards their reproductive behavior. We can also assume that the morphological, genetic, and chemical diversity found among the species of Phalangopsidae reflects in the behaviors of pair-formation, courtship, copulation, and post-copulation, leading to a diversity of copulation positions, duration of the stages, methods of attracting partners and parental investment. The description of Phalangopsidae mating patterns can provide important information for future evolutionary and phylogenetic studies, apart from useful for distinguishing cryptic species.

17.
Zootaxa ; 5343(1): 31-54, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-38221389

RESUMO

A new species of praying mantis, Metaphotina austri sp. n., is described from the Caatinga biome in Brazil. The species can be easily distinguished from its congeners by its small body size and diagnostic characters found on the head, wings, and male genitalia. Distributional data compiled from specimen labels, historical literature, and the citizen science platform iNaturalist showed that M. austri sp. n. is mainly associated with the northernmost and driest region of the Caatinga, known as the Depresso Sertaneja Setentrional. Ecological and geographical data about the new species, as well as comments on the diversity of Mantodea in the Caatinga, are provided, highlighting the importance of crowdsourced data for a more comprehensive understanding of praying mantis species distribution and their natural history.


Assuntos
Ciência do Cidadão , Mantódeos , Animais , Masculino , Brasil , Ecossistema , Tamanho Corporal
19.
Am J Primatol ; 84(11): e23437, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36128630

RESUMO

Most primate taxa are threatened by extinction and their populations are decreasing. The persistence of primates is thus conditional on conservation actions aimed at protecting them and their habitat. Here, we focus on the conservation of mantled howler monkeys (Alouatta palliata) in the Los Tuxtlas Biosphere Reserve, Mexico. Following the creation of the reserve in 1998, habitat availability and howler monkey abundance increased, suggesting that progress was being made in terms of the conservation of this species. Recent events, however, suggest otherwise, as mantled howler monkey habitat within the biosphere reserve is being disturbed by mining operations endorsed by the Mexican government. We report this case to raise awareness about the challenges for primate and habitat conservation in protected areas.


Assuntos
Alouatta , Fragilidade , Animais , Ecossistema , México
20.
J Glob Antimicrob Resist ; 31: 38-44, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35948241

RESUMO

OBJECTIVES: In contrast to other qnr families, qnrVC has been reported mainly in Vibrio spp. and inserted in class 1 integrons. This study aimed to identify the variants of qnrVC genes detected in Klebsiella pneumoniae carbapenemase-2-producing Enterobacter and Klebsiella strains isolated from Brazilian coastal waters and the genetic contexts associated with their occurrence. METHODS: qnrVC variants were identified by Sanger sequencing. Stains were typified by pulsed-field gel electrophoresis. Antimicrobial susceptibility testing, conjugation assays, and whole genome sequencing (WGS) were applied to identify the strains' antimicrobial resistance profile, qnrVC and blaKPC-2 co-transference, and qnrVC genetic context. RESULTS: qnrVC1 was identified in 15 Enterobacter and 3 Klebsiella, and qnrVC4 in 2 Enterobacter strains. Pulsed-field gel electrophoresis revealed 12 clonal profiles of Enterobacter and one of Klebsiella. Strains were resistant to aminoglycosides, beta-lactams, fosfomycin, quinolones, and sulfamethoxazole-trimethoprim. Co-transference of qnrVC and blaKPC-2 were obtained from five representative Enterobacter strains, which showed resistance to ampicillin and amoxicillin-clavulanate, and reduced susceptibility to extended-spectrum cephalosporins, meropenem, and ciprofloxacin. WGS analysis from representative strains revealed one K. quasipneumoniae subsp. similipneumoniae, one E. soli, four E. kobei, and seven isolates belonging to Enterobacter Taxon 3. Long-read WGS showed qnrVC and blaKPC-2 were carried by the same replicon on Klebsiella and Enterobacter strains, and the qnrVC association with not previously described genetic environments composed of insertion sequences and truncated genes. These contexts occurred in small- and high-molecular-weight plasmids belonging to IncFII, IncP6, pKPC-CAV1321, and IncU groups. CONCLUSION: Our results suggest that the dissemination of qnrVC among Enterobacterales in Brazilian coastal waters is associated with several genetic recombination events.


Assuntos
Enterobacter , Klebsiella , Antibacterianos/farmacologia , Enterobacter/genética , Klebsiella/genética , Klebsiella pneumoniae/genética
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