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1.
J Invertebr Pathol ; 205: 108128, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38735430

RESUMO

The crayfish plague pathogen Aphanomyces astaci has been implicated in a number of mass mortalities and irreversible population declines of native crayfish across Europe. At present, the reservoirs of the pathogen in Europe are mainly populations of invasive North American crayfish species. In southwestern Europe, including France, a particularly widespread invader is the red swamp crayfish Procambarus clarkii. Recent distribution data confirm that P. clarkii is present in at least 75 French departments, i.e. more than 78% of those in metropolitan France. We analysed the prevalence and pathogen load of A. astaci in 42 populations of this species in western France (Nouvelle Aquitaine region), where the species is most densely distributed, particularly in a wide range of environments around the Gironde estuary. The pathogen was detected by two different quantitative PCR assays in more than three quarters of the populations studied (34 out of 42); 163 out of 480 analysed crayfish individuals tested positive for the presence of A. astaci. In most cases, individual infection levels were very low, detectable with quantitative PCR but not sufficient for pathogen genotyping. In seven P. clarkii individuals from four populations, however, we were able to assess A. astaci variation by microsatellite markers and sequencing of mitochondrial markers. All these host specimens carried A. astaci genotype group D, haplotype d1, which has caused the majority of crayfish plague outbreaks in neighbouring Spain. In contrast, the French outbreaks genotyped to date (including eight newly analysed in this study) were mostly caused by strains of genotype group B, specific to the signal crayfish Pacifastacus leniusculus. Haplotype d1 found in P. clarkii was involved in one of the newly characterised outbreaks. Our study confirms that P. clarkii is a potentially important reservoir of the crayfish plague pathogen in France, but not the main source of the pathogen in mass mortalities of A. pallipes, probably due to different ecological requirements of the different invasive host crayfish. However, as P. clarkii continues to spread, the threat posed by this species to native crayfish is likely to increase.


Assuntos
Aphanomyces , Astacoidea , Animais , Astacoidea/microbiologia , Aphanomyces/genética , Aphanomyces/fisiologia , França/epidemiologia , Prevalência , Espécies Introduzidas , Brancos
2.
J Invertebr Pathol ; 202: 108040, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38081448

RESUMO

Ornamental trade has become an important introduction pathway of non-native aquatic species worldwide. Correspondingly, there has been an alarming increase in the number of established crayfish of aquarium origin in Europe over the previous decade. The oomycete Aphanomyces astaci, the pathogen causing crayfish plague responsible for serious declines of European crayfish populations, is dispersed with introduced North American crayfish. The role of ornamental taxa in introducing and spreading different genotypes of this pathogen in open waters remains unclear. We investigated the distribution, prevalence, and diversity of A. astaci in Budapest, Hungary, which became a hotspot of aquarium crayfish introductions. Their establishment in this area was facilitated by locally abundant thermal waters. We screened for A. astaci in six host taxa from 18 sites sampled between 2018 and 2021: five cambarids (Cambarellus patzcuarensis, Faxonius limosus, Procambarus alleni, P. clarkii, P. virginalis) and one native astacid (Pontastacus leptodactylus). The pathogen was confirmed at five sampled sites in four host taxa: P. virginalis, P. clarkii, F. limosus, and for the first time in European open waters also in P. alleni. Genotyping was successful only in individuals from two different brooks where multiple host species coexisted but revealed unexpected patterns. Mitochondrial B-haplogroup of A. astaci, previously usually reported from Pacifastacus leniusculus or infected European species, was detected in P. virginalis at both sites, and in both F. limosus and P. virginalis sampled from a thermally stable tributary of Barát brook in 2018. In contrast, A-haplogroup of A. astaci was detected in coexisting F. limosus, P. virginalis and P. clarkii sampled in the same watercourse just a few hundred meters downstream in 2020. Additional genotyping methods indicated that a previously unknown A. astaci strain was associated with the latter haplogroup. One P. virginalis individual from 2020 was apparently co-infected by strains representing both mitochondrial haplogroups. The results indicated multiple sources of A. astaci in Budapest, likely directly associated with the introduction of ornamental species, interspecific transmission of this pathogen among ornamental hosts, and potential for a quick spatial or temporal turnover of dominant A. astaci strains at a certain locality. This highlights that in regions with high richness of potential A. astaci hosts, host taxon/pathogen genotype combinations become unpredictable, which might prevent reliable genotyping of pathogen sources in local crayfish mass mortalities.


Assuntos
Aphanomyces , Astacoidea , Humanos , Animais , Aphanomyces/genética , Europa (Continente) , Genótipo , Técnicas de Genotipagem
3.
J Environ Manage ; 352: 120009, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38184871

RESUMO

Land managers must find a compromise between rapidly changing landscapes and biodiversity conservation through ecological networks. Estimating ecological networks is a key approach to enhance or maintain functional connectivity by identifying the nodes and links of a graph, which represent habitats and their corresponding functional corridors, respectively. To understand the current state of biodiversity, it is necessary to consider dynamic landscape connectivity while relying on relevant land cover maps. Although a current land cover map is relatively easy to produce using existing data, this is challenging for past landscapes. Here we investigated the impact of changes in landscape connectivity in an urban landscape at a fine scale on the habitat availability of two bird species: the tree pipit Anthus trivialis and the short-toed treecreeper Certhia brachydactyla. These species, exhibiting different niche ecologies, have shown contrasting population trends at a medium-term scale. The occurrences of C. brachydactyla were better correlated with resistance values that maximise the use of corridors, whereas the occurrences of A. trivialis better fitted with intermediate resistance values. The statistical approach indirectly highlighted relevant information about the ecology the capacity of both species to use urban habitats. Landscape connectivity increased for both species over the 24-year study period and may have implications for local abundances, which could explain, at the national scale, the increase in populations of C. brachydactyla, but not the decrease in populations of A. trivialis. Thus, more attention must be paid on rural habitats and their associated species that are more impacted by human activities, but efforts could also be achieved in urban areas especially for highly corridor-dependent species. Studying dynamic landscape connectivity at a fine scale is essential for estimating past and future land cover changes and their associated impacts on ecological networks, to better reconcile human and biodiversity concerns in land management.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Humanos , Biodiversidade , Aves , Atividades Humanas
4.
Nat Chem Biol ; 17(3): 280-290, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33462494

RESUMO

Although most acute skin wounds heal rapidly, non-healing skin ulcers represent an increasing and substantial unmet medical need that urgently requires effective therapeutics. Keratinocytes resurface wounds to re-establish the epidermal barrier by transitioning to an activated, migratory state, but this ability is lost in dysfunctional chronic wounds. Small-molecule regulators of keratinocyte plasticity with the potential to reverse keratinocyte malfunction in situ could offer a novel therapeutic approach in skin wound healing. Utilizing high-throughput phenotypic screening of primary keratinocytes, we identify such small molecules, including bromodomain and extra-terminal domain (BET) protein family inhibitors (BETi). BETi induce a sustained activated, migratory state in keratinocytes in vitro, increase activation markers in human epidermis ex vivo and enhance skin wound healing in vivo. Our findings suggest potential clinical utility of BETi in promoting keratinocyte re-epithelialization of skin wounds. Importantly, this novel property of BETi is exclusively observed after transient low-dose exposure, revealing new potential for this compound class.


Assuntos
Proteínas de Ciclo Celular/genética , Epiderme/efeitos dos fármacos , Reepitelização/efeitos dos fármacos , Úlcera Cutânea/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/farmacologia , Fatores de Transcrição/genética , Ferimentos não Penetrantes/tratamento farmacológico , Animais , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Modelos Animais de Doenças , Epiderme/metabolismo , Epiderme/patologia , Transferência Ressonante de Energia de Fluorescência , Regulação da Expressão Gênica , Ensaios de Triagem em Larga Escala , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Precursores de Proteínas/antagonistas & inibidores , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Reepitelização/genética , Úlcera Cutânea/genética , Úlcera Cutânea/metabolismo , Úlcera Cutânea/patologia , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Transcrição Gênica , Ferimentos não Penetrantes/genética , Ferimentos não Penetrantes/metabolismo , Ferimentos não Penetrantes/patologia
5.
Biol Lett ; 19(1): 20220457, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36628964

RESUMO

In the isopod Armadillidium vulgare, many females produce progenies with female-biased sex ratios, owing to two feminizing sex ratio distorters (SRD): Wolbachia endosymbionts and the f element. We investigated the distribution and population dynamics of these SRD and mitochondrial DNA variation in 16 populations from Europe and Japan. Confirming and extending results from the 1990s, we found that the SRD are present at variable frequencies in populations and that the f element is overall more frequent than Wolbachia. The two SRD never co-occur at high frequency in any population, suggesting an apparent mutual exclusion. We also detected Wolbachia or the f element in some males, which probably reflects insufficient titer to induce feminization or presence of masculinizing alleles. Our results are consistent with a single integration event of a Wolbachia genome in the A. vulgare genome at the origin of the f element, which contradicts an earlier hypothesis of frequent losses and gains. We identified strong linkage between Wolbachia strains and mitochondrial haplotypes, but no association between the f element and mitochondrial background. Our results open new perspectives on SRD evolutionary dynamics in A. vulgare, the evolution of genetic conflicts and their impact on the variability of sex determination systems.


Assuntos
Isópodes , Wolbachia , Masculino , Animais , Feminino , Isópodes/genética , Razão de Masculinidade , Haplótipos , Europa (Continente) , Japão , Wolbachia/genética
6.
Int J Gynecol Cancer ; 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37844964

RESUMO

OBJECTIVE: In Belgium there is no centralization of surgery for ovarian cancer, with more than 100 centers treating around 800 cases per year. In 2017 a network with several collaborating hospitals was established to centralize surgery for ovarian cancer (UCLouvain Network of Gynecological Oncology; UNGO) following publication of the European Society of Gynecological Oncology (ESGO) recommendations and quality criteria for surgery of advanced ovarian cancer. We obtained ESGO accreditation in 2019. METHODS: We retrospectively collected data associated with patients undergoing surgery in our institution from 2007 to 2016, before the creation of the network (cohort 1) and, following the establishment of UNGO (2017-2021), patients undergoing surgery were prospectively registered in a REDCap database (cohort 2). The outcomes of the two cohorts were compared. RESULTS: A total of 314 patients underwent surgery in our institution from 2007 and 2021: 7.5 patients/year in cohort 1 (retrospective, 2007-2016) and 40.8 patients/year in cohort 2 (after network creation, 2017-2021). Median disease-free survival was increased from 16.5 months (range 13.2-20.4) in cohort 1 to 27.1 months (range 21.5-33.2) in cohort 2 (p=0.0004). In cohort 2, the rate of patients with residual disease at the end of the surgery was significantly less (18.7% vs 8.8%, p=0.023), although more patients in cohort 1 received neoadjuvant chemotherapy (89% vs 54%, p<0.001). However, there was a higher rate of complications in the patients in cohort 2 (18.8% vs 30%, p=0.041). CONCLUSION: Our study shows that, with the help of ESGO and its recommendations, we have been able to create an efficient advanced ovarian cancer centralized network and this may provide an improvement in the quality of care.

7.
J Fish Biol ; 101(5): 1225-1234, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36054289

RESUMO

Minnows of the genus Phoxinus are common and an often highly abundant fish species in Palearctic freshwater habitats. Phoxinus species have a complex evolutionary history, phylogenetic relationships are not well understood and there are a number of unresolved taxonomic problems. There are currently 23 different mitochondrial genetic lineages identified in the genus Phoxinus, 13 of which are recognized as valid species. The taxonomic status of these lineages requires resolution, including the degree to which they can interbreed. Suitable nuclear molecular markers for studies of population divergence and interbreeding between morphotypes and mitochondrial lineages are lacking for Phoxinus species. Therefore, the authors developed a set of microsatellite markers using genomic information from Phoxinus lumaireul and tested their suitability for this and two related species, Phoxinus krkae and Phoxinus marsilii. Out of 16 microsatellite candidate loci isolated, 12 were found to be in Hardy-Weinberg equilibrium when tested on two P. lumaireul senso lato populations. Seven loci amplified across the three species, enabling the study of intraspecific genetic diversity and population structure within P. marsilii and P. krkae. The markers were able to clearly resolve differences among the three tested species, including the recently described P. krkae, and are therefore suitable for the detection of introgression and hybridization among populations consisting of mixtures of two or more of P. lumaireul s. l., P. marsilii and P. krkae.


Assuntos
Cyprinidae , Cipriniformes , Animais , Filogenia , Cipriniformes/genética , Repetições de Microssatélites , Cyprinidae/genética , Genes Mitocondriais
8.
BMC Genomics ; 20(1): 335, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053062

RESUMO

BACKGROUND: The recently published complete mitogenome of the European lobster (Homarus gammarus) that was generated using long-range PCR exhibits unusual gene composition (missing nad2) and gene rearrangements among decapod crustaceans with strong implications in crustacean phylogenetics. Such atypical mitochondrial features will benefit greatly from validation with emerging long read sequencing technologies such as Oxford Nanopore that can more accurately identify structural variation. RESULTS: We re-sequenced the H. gammarus mitogenome on an Oxford Nanopore Minion flowcell and performed a long-read only assembly, generating a complete mitogenome assembly for H. gammarus. In contrast to previous reporting, we found an intact mitochondrial nad2 gene in the H. gammarus mitogenome and showed that its gene organization is broadly similar to that of the American lobster (H. americanus) except for the presence of a large tandemly duplicated region with evidence of pseudogenization in one of each duplicated protein-coding genes. CONCLUSIONS: Using the European lobster as an example, we demonstrate the value of Oxford Nanopore long read technology in resolving problematic mitogenome assemblies. The increasing accessibility of Oxford Nanopore technology will make it an attractive and useful tool for evolutionary biologists to verify new and existing unusual mitochondrial gene rearrangements recovered using first and second generation sequencing technologies, particularly those used to make phylogenetic inferences of evolutionary scenarios.


Assuntos
Evolução Biológica , Biologia Computacional/métodos , Duplicação Gênica , Genoma Mitocondrial , Proteínas Mitocondriais/genética , Nanoporos , Nephropidae/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sequenciamento de Nucleotídeos em Larga Escala , Família Multigênica , Nephropidae/metabolismo , Filogenia , Análise de Sequência de DNA , Homologia de Sequência
9.
BMC Biol ; 16(1): 43, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29669603

RESUMO

BACKGROUND: Oomycetes are a group of filamentous eukaryotic microorganisms that have colonized all terrestrial and oceanic ecosystems, and they include prominent plant pathogens. The Aphanomyces genus is unique in its ability to infect both plant and animal species, and as such exemplifies oomycete versatility in adapting to different hosts and environments. Dissecting the underpinnings of oomycete diversity provides insights into their specificity and pathogenic mechanisms. RESULTS: By carrying out genomic analyses of the plant pathogen A. euteiches and the crustacean pathogen A. astaci, we show that host specialization is correlated with specialized secretomes that are adapted to the deconstruction of the plant cell wall in A. euteiches and protein degradation in A. astaci. The A. euteiches genome is characterized by a large repertoire of small secreted protein (SSP)-encoding genes that are highly induced during plant infection, and are not detected in other oomycetes. Functional analysis revealed an SSP from A. euteiches containing a predicted nuclear-localization signal which shuttles to the plant nucleus and increases plant susceptibility to infection. CONCLUSION: Collectively, our results show that Aphanomyces host adaptation is associated with evolution of specialized secretomes and identify SSPs as a new class of putative oomycete effectors.


Assuntos
Aphanomyces/patogenicidade , Genômica/métodos , Aclimatação/genética , Aclimatação/fisiologia , Animais , Aphanomyces/genética , Oomicetos/genética , Oomicetos/patogenicidade , Doenças das Plantas/microbiologia
10.
Mol Phylogenet Evol ; 127: 320-331, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29800651

RESUMO

The infraorder Anomura consists of a morphologically and ecologically heterogeneous group of decapod crustaceans, and has attracted interest from taxonomists for decades attempting to find some order out of the seemingly chaotic diversity within the group. Species-level diversity within the Anomura runs the gamut from the "hairy" spindly-legged yeti crab found in deep-sea hydrothermal vent environments to the largest known terrestrial invertebrate, the robust coconut or robber crab. Owing to a well-developed capacity for parallel evolution, as evidenced by the occurrence of multiple independent carcinization events, Anomura has long tested the patience and skill of both taxonomists attempting to find order, and phylogeneticists trying to establish stable hypotheses of evolutionary inter-relationships. In this study, we performed genome skimming to recover the mitogenome sequences of 12 anomuran species including the world's largest extant invertebrate, the robber crab (Birgus latro), thereby over doubling these resources for this group, together with 8 new brachyuran mitogenomes. Maximum-likelihood (ML) and Bayesian-inferred (BI) phylogenetic reconstructions based on amino acid sequences from mitogenome protein-coding genes provided strong support for the monophyly of the Anomura and Brachyura and their sister relationship, consistent with previous studies. The majority of relationships within families were supported and were largely consistent with current taxonomic classifications, whereas many relationships at higher taxonomic levels were unresolved. Nevertheless, we have strong support for a polyphyletic Paguroidea and recovered a well-supported clade of a subset of paguroids (Diogenidae + Coenobitidae) basal to all other anomurans, though this requires further testing with greater taxonomic sampling. We also introduce a new feature to the MitoPhAST bioinformatics pipeline (https://github.com/mht85/MitoPhAST) that enables the extraction of mitochondrial gene order (MGO) information directly from GenBank files and clusters groups based on common MGOs. Using this tool, we compared MGOs across the Anomura and Brachyura, identifying Anomura as a taxonomic "hot spot" with high variability in MGOs among congeneric species from multiple families while noting the broad association of highly-rearranged MGOs with several anomuran lineages inhabiting extreme niches. We also demonstrate the value of MGOs as a source of novel synapomorphies for independently reinforcing tree-based relationships and for shedding light on relationships among challenging groups such as the Aegloidea and Lomisoidea that were unresolved in phylogenetic reconstructions. Overall, this study contributes a substantial amount of new genetic material for Anomura and attempts to further resolve anomuran evolutionary relationships where possible based on a combination of sequence and MGO information. The new feature in MitoPhAST adds to the relatively limited number of bioinformatics tools available for MGO analyses, which can be utilized widely across animal groups.


Assuntos
Anomuros/classificação , Anomuros/genética , Ordem dos Genes , Rearranjo Gênico , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Braquiúros/classificação , Braquiúros/genética , Genes Mitocondriais , Genoma Mitocondrial
11.
Mol Phylogenet Evol ; 103: 26-40, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27404041

RESUMO

In this study, the evolutionary history of the white-clawed crayfish (WCC) was evaluated using large-scale datasets comprising >1350 specimens from the entire distribution range. Using species delimitation methods on mitochondrial DNA (mtDNA) sequences, we propose four primary species hypotheses for WCC. Sequences for several nuclear regions were screened but none showed significant variation within WCC. This result favours a single secondary species hypothesis and indicates the existence of a mito-nuclear discordance in WCC. Therefore, mtDNA groups were considered only as genetic units that carry information about ancient divergences within WCC and not as taxonomic units. The reconstruction of ancestral ranges and divergence time estimates were used to link the current genetic structure with paleogeographic processes. These results showed that the emergence of mtDNA groups in WCC could be related to the Messinian Salinity Crisis, the climate cooling during the Pliocene and Pleistocene, and (paleo)shifting of the Adriatic Sea coastline in the Padanovenezian Plain. The most recent common ancestor of the mtDNA groups most likely originated from Dalmatia (eastern Adriatic coast) as indicated by the reconstruction of ancestral ranges. This ecoregion, along with the Gulf of Venice Drainages, harbours a high genetic diversity and should be emphasised as an area of the highest conservation priority.


Assuntos
Astacoidea/classificação , Animais , Astacoidea/genética , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , DNA Mitocondrial/classificação , DNA Mitocondrial/genética , Variação Genética , Filogenia , Filogeografia , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
J Invertebr Pathol ; 141: 18-23, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27756651

RESUMO

Wolbachia are a group of intracellular bacteria that cause reproductive alterations in arthropods. Here, we describe the effects of two environmental factors (crowding and temperature) on phenotypic expression of feminization, the host's fecundity and Wolbachia infection intensity among life cycle stages in the naturally Wolbachia-infected copepod, Mesocyclops thermocyclopoides. The copepod was first found to be co-infected with Wolbachia A- and B-supergroups Wolbachia strains based on wsp primers. The relative Wolbachia infection intensity within individuals was determined using quantitative real-time PCR and was significantly higher in the B-supergroup than in the A-supergroup. Experimental results of temperature effect on bacterial density in each developmental stage revealed a significant decrease in Wolbachia infection intensity following exposure to high temperature (37°C) in both sexes and implied that Wolbachia might survive in room temperature (25°C) better than in high temperature. Experimental results of crowding effects on Wolbachia infection intensity suggested a negative correlation between copepod nauplii and Wolbachia infection intensity. No effect of rearing temperature on the sex ratio was reported although the fecundity was significantly decreased by high temperature. The results showed that Wolbachia infection intensity to be correlated with crowding conditions and was decreased following exposure of elevated temperature.


Assuntos
Copépodes/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Wolbachia , Animais , Feminino , Fertilidade , Temperatura Alta , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Razão de Masculinidade
13.
Dis Aquat Organ ; 118(1): 45-53, 2016 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-26865234

RESUMO

The Oomycete Aphanomyces astaci is an obligate crayfish parasite that co-evolved with American crayfish species, and they therefore generally live in a balanced relationship. On the contrary, European native crayfish are highly susceptible to A. astaci, and infestation with it causes development of the lethal disease termed crayfish plague. Until now, 5 A. astaci strains have been described from the freshwater crayfish present in Europe. In this study we aimed to investigate the occurrence of the pathogen A. astaci in Croatian native and non-native crayfish populations, as well as to genotype established strains using microsatellite markers and obtain information on the pathogen's epidemiology. Our results showed that the pathogen is widespread in both native and non-native crayfish populations. Agent level, when positive, in non-native crayfish was generally low; in native species it was higher. Genotyping from microsatellites proved the presence of the B (Ps) strain in non-native species (Pacifastacus leniusculus), while the A (As) strain was detected from viable native species (Astacus astacus and Austropotamobius torrentium) that are distributed in areas lacking non-native crayfish. The genotype from A. torrentium differed from a typical A (As) by 1 allele. Strain B (Ps) was identified in native Astacus leptodactylus from the population that co-occurs with P. leniuscuslus. Interestingly, in 1 A. leptodactylus population both A (As) and B (Ps) strains were present.


Assuntos
Aphanomyces/fisiologia , Astacoidea/microbiologia , Animais , Croácia , Interações Hospedeiro-Patógeno , Reação em Cadeia da Polimerase em Tempo Real
14.
J Invertebr Pathol ; 132: 115-124, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26410255

RESUMO

European crayfish are sensitive to the crayfish plague pathogen, Aphanomyces astaci, carried by North American crayfish species due to their less effective immune defence mechanisms against this disease. During a controlled infection experiment with a susceptible crayfish species Astacus astacus using three A. astaci strains (representing genotype groups A, B, and E), we investigated variation in their virulence and in crayfish immune defence indicators (haemocyte density, phenoloxidase activity, and production of reactive oxygen species). Experimental crayfish were exposed to two dosages of A. astaci spores (1 and 10 spores mL(-1)). The intensity and timing of the immune response differed between the strains as well as between the spore concentrations. Stronger and faster change in each immune parameter was observed in crayfish infected with two more virulent strains, indicating a relationship between crayfish immune response and A. astaci virulence. Similarly, the immune response was stronger and was observed earlier for the higher spore concentration. For the first time, the virulence of a strain of the genotype group E (isolated from Orconectes limosus) was experimentally tested. Total mortality was reached after 10 days for the two higher spore dosages (10 and 100 spores mL(-1)), and after 16 days for the lowest (1 spore mL(-1)), revealing equally high and rapid mortality as caused by the genotype group B (from Pacifastacus leniusculus). No mortality occurred after infection with genotype group A during 60 days of the experimental trial.


Assuntos
Aphanomyces/imunologia , Astacoidea/imunologia , Imunidade Inata , Animais , Aphanomyces/genética , Aphanomyces/patogenicidade , Astacoidea/parasitologia , Contagem de Células Sanguíneas , Genótipo , Hemócitos , Monofenol Mono-Oxigenase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Virulência
15.
Ecol Evol ; 14(4): e11191, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38571792

RESUMO

The pace of biological invasions has increased in recent decades, leading to multiple invasions and the potential dominance of invasive species, destabilizing local ecological networks. This provides opportunities to study new ecological species interactions, including predation. Tropical freshwaters have been particularly concerned by aquatic invasions and we focused here on the Martinique island (Lesser Antilles). We examined the predator-prey relationships involving invasive Thiarid snails (Tarebia granifera and Melanoides tuberculata) and the native Neritina punctulata, both confronted with a newcomer predator, the redclaw crayfish (Cherax quadricarinatus). We conducted several mesocosm experiments to assess the impact of crayfish predation on snail survival and the passive and active antipredator responses of snails. A first experiment indicated snail survival rates between 50% and 80%, depending on crayfish size and sex. Notably, there was a negative correlation between snail survival and male crayfish size and the predation method (shell crushing vs. "body sucking") varied with crayfish size. The second experiment suggested no refuge size for snails, with both very small (<5 mm) and very large (>5 mm) unable to escape predation, regardless of crayfish size (from 77 to 138 mm) or sex. Finally, we investigated the escape behavior of Thiarids regarding three crayfish cues. Melanoides tuberculata tend to bury in the substrate and T. granifera to climb up aquarium walls, what was expected from their shell morphologies, and both responding to crayfish cues within minutes. Overall, C. quadricarinatus proves to be an efficient snail predator with limited escape options for snails, potentially contributing to the decline of certain snail populations in Martinique. This omnivorous predator might impact other native species across different groups, including shrimps and fish. Our study underscores the urgent need for monitoring efforts, solidifying the redclaw crayfish reputation as a dangerous invasive species for freshwater macrobenthic faunas worldwide.

16.
Data Brief ; 52: 109829, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38093857

RESUMO

The land cover data presented here is a reconstruction of the past landscape (1993) at Very High Resolution (VHR) for the city of Poitiers, France. This reconstruction is based on multiple sources of images and data. We combined the strengths of both mono-temporal and multi-temporal classifications. Orthophotos were created at a spatial resolution of 0.5 m using aerial raw images from the French National Geographic Institute (IGN), taken during two aerial missions in July and August 1993. These orthophotos were merged at a spatial resolution of 5 m to conduct a first object-based classification using Landsat-5 TM images. The goal was to identify croplands, grasslands, coniferous and deciduous forests, urban areas, water bodies, and shadows. This learning-based classification employed a dataset consisting of 1371 polygons and demonstrated strong classification performances, achieving an overall accuracy of 86.31% and a kappa index of 0.832. On the other hand, mono-temporal classifications at a 0.5 m spatial resolution were carried out on each orthophoto to extract trees and herbaceous vegetation, especially in urban contexts. As mono-temporal classifications contained less information, we used a larger number of polygons for the learning step: 3849 and 5173 polygons for the northern and southern classifications, respectively. The segmentation step performed better in urban areas compared to rural areas. Consequently, the performance of classifications was evaluated separately for both contexts. Urban areas exhibited excellent performances, achieving kappa indices of 0.897 and 0.881 for the northern and southern classifications, respectively, whereas only tree vegetation was accurately detected in rural areas. To compensate for the lack of information such as buildings, railways, or roads, we modified the BD TopoⓇ dataset from IGN. This land cover map provides highly detailed information, facilitating the understanding of urban sprawl and changes in urban and rural vegetation surrounding the city of Poitiers. Due to these reasons, this freely accessible map can be utilized by researchers, land managers, and private companies for addressing urban and ecological challenges.

17.
J Clin Med ; 13(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38541772

RESUMO

INTRODUCTION: Surgery is the cornerstone of ovarian cancer treatment. However, surgery and perioperative inflammation have been described as potentially pro-metastagenic. In various animal models and other human cancers, intraoperative administration of non-steroidal anti-inflammatory drugs (NSAIDs) appears to have a positive impact on patient outcomes. MATERIALS AND METHODS: In this unicentric retrospective study, we provide an exploratory analysis of the safety and potential benefit of intraoperative administration of ketorolac on the outcome of patients undergoing surgery for ovarian cancer. The study population included all patients who were given a diagnosis of ovarian, fallopian tube or peritoneal cancer by the multidisciplinary oncology committee (MOC) of the Cliniques universitaires Saint-Luc between 2015 and 2020. RESULTS: We included 166 patients in our analyses, with a median follow-up of 21.8 months. Both progression-free survival and overall survival were superior in patients who received an intraoperative injection of ketorolac (34.4 months of progression-free survival in the ketorolac group versus 21.5 months in the non-ketorolac group (p = 0.002), and median overall survival was not reached in either group but there was significantly higher survival in the ketorolac group (p = 0.004)). We also performed subgroup analyses to minimise bias due to imbalance between groups on factors that could influence patient survival, and the group of patients receiving ketorolac systematically showed a better outcome. Uni- and multivariate analyses confirmed that administration of ketorolac intraoperatively was associated with better progression-free survival (HR = 0.47 on univariate analysis and 0.43 on multivariate analysis, p = 0.003 and 0.023, respectively). In terms of complications, there were no differences between the two groups, either intraoperatively or postoperatively. CONCLUSION: Our study has shown a favourable association between the use of ketorolac during surgery and the postoperative progression of ovarian cancer in a group of 166 patients, without any rise in intra- or postoperative complications. These encouraging results point to the need for a prospective study to confirm the benefit of intraoperative administration of ketorolac in ovarian cancer surgery.

18.
ACS Chem Biol ; 19(5): 1142-1150, 2024 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-38655884

RESUMO

The ARID1A and ARID1B subunits are mutually exclusive components of the BAF variant of SWI/SNF chromatin remodeling complexes. Loss of function mutations in ARID1A are frequently observed in various cancers, resulting in a dependency on the paralog ARID1B for cancer cell proliferation. However, ARID1B has never been targeted directly, and the high degree of sequence similarity to ARID1A poses a challenge for the development of selective binders. In this study, we used mRNA display to identify peptidic ligands that bind with nanomolar affinities to ARID1B and showed high selectivity over ARID1A. Using orthogonal biochemical, biophysical, and chemical biology tools, we demonstrate that the peptides engage two different binding pockets, one of which directly involves an ARID1B-exclusive cysteine that could allow covalent targeting by small molecules. Our findings impart the first evidence of the ligandability of ARID1B, provide valuable tools for drug discovery, and suggest opportunities for the development of selective molecules to exploit the synthetic lethal relationship between ARID1A and ARID1B in cancer.


Assuntos
Proteínas de Ligação a DNA , Peptídeos , RNA Mensageiro , Fatores de Transcrição , Humanos , Ligantes , Peptídeos/química , Peptídeos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ligação Proteica , Sítios de Ligação
19.
Genome ; 55(3): 234-44, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22376074

RESUMO

Metazoan mitochondrial DNA (mtDNA) is generally composed of circular monomeric molecules. However, a few exceptions do exist and among them two terrestrial isopods Armadillidium vulgare and Porcellionides pruinosus have an atypical mtDNA composed of linear monomers associated with circular "head-to-head" dimers: a very unusual structure for animal mtDNA genome. To assess the distribution of this atypical mtDNA among isopods, we performed RFLP and Southern blot analyses on mtDNA of 16 terrestrial (Oniscidea family) and two aquatic isopod species: the marine Sphaeroma serratum (suborder Flabellifera, sister group of Oniscidea) and the freshwater Asellus aquaticus (Asellota, early derived taxon of isopod). The atypical mtDNA structure was observed in 15 terrestrial isopod species and A. aquaticus, suggesting a wide distribution of atypical mtDNA among isopods. However, a typical metazoan mtDNA structure was detected in the marine isopod S. serratum and the Oniscidea Ligia oceanica . Our results suggest two possible scenarios: an early origin of the atypical mtDNA in isopods followed by reversion to the typical ancestral mtDNA structure for several species, or a convergent appearance of the atypical mtDNA structure in two isopod suborders. We compare this distribution of the atypical mtDNA structure with the presence of a heteroplasmy also observed in the mtDNA of several terrestrial isopod species. We discuss if this transmitted heteroplasmy is vectored by the atypical mtDNA and its impact on the maintenance of the atypical mtDNA in isopods.


Assuntos
DNA Mitocondrial/genética , Isópodes/genética , Conformação de Ácido Nucleico , Animais , Southern Blotting , Polimorfismo de Fragmento de Restrição , Especificidade da Espécie
20.
Genet Mol Biol ; 35(4 (suppl)): 980-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23413179

RESUMO

Wolbachia are endosymbiotic bacteria that commonly infect arthropods, inducing certain phenotypes in their hosts. So far, no endemic South American species of terrestrial isopods have been investigated for Wolbachia infection. In this work, populations from two species of Balloniscus (B. sellowii and B. glaber) were studied through a diagnostic PCR assay. Fifteen new Wolbachia 16S rDNA sequences were detected. Wolbachia found in both species were generally specific to one population, and five populations hosted two different Wolbachia 16S rDNA sequences. Prevalence was higher in B. glaber than in B. sellowii, but uninfected populations could be found in both species. Wolbachia strains from B. sellowii had a higher genetic variation than those isolated from B. glaber. AMOVA analyses showed that most of the genetic variance was distributed among populations of each species rather than between species, and the phylogenetic analysis suggested that Wolbachia strains from Balloniscus cluster within Supergroup B, but do not form a single monophyletic clade, suggesting multiple infections for this group. Our results highlight the importance of studying Wolbachia prevalence and genetic diversity in Neotropical species and suggest that South American arthropods may harbor a great number of diverse strains, providing an interesting model to investigate the evolution of Wolbachia and its hosts.

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