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1.
Environ Pollut ; 349: 123692, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38462194

RESUMO

Estimating the consequences of environmental changes, specifically in a global change context, is essential for conservation issues. In the case of pollutants, the interest in using an evolutionary approach to investigate their consequences has been emphasized since the 2000s, but these studies remain rare compared to the characterization of direct effects on individual features. We focused on the study case of anthropogenic ionizing radiation because, despite its potential strong impact on evolution, the scarcity of evolutionary approaches to study the biological consequences of this stressor is particularly true. In this study, by investigating some particular features of the biological effects of this stressor, and by reviewing existing studies on evolution under ionizing radiation, we suggest that evolutionary approach may help provide an integrative view on the biological consequences of ionizing radiation. We focused on three topics: (i) the mutagenic properties of ionizing radiation and its disruption of evolutionary processes, (ii) exposures at different time scales, leading to an interaction between past and contemporary evolution, and (iii) the special features of contaminated areas called exclusion zones and how evolution could match field and laboratory observed effects. This approach can contribute to answering several key issues in radioecology: to explain species differences in the sensitivity to ionizing radiation, to improve our estimation of the impacts of ionizing radiation on populations, and to help identify the environmental features impacting organisms (e.g., interaction with other pollution, migration of populations, anthropogenic environmental changes). Evolutionary approach would benefit from being integrated to the ecological risk assessment process.


Assuntos
Evolução Biológica , Radiação Ionizante , Animais , Poluição Ambiental
2.
BMC Biol ; 21(1): 164, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37525144

RESUMO

BACKGROUND: Individual functional modifications shape the ability of wildlife populations to cope with anthropogenic environmental changes. But instead of adaptive response, human-altered environments can generate a succession of deleterious functional changes leading to the extinction of the population. To study how persistent anthropogenic changes impacted local species' population status, we characterised population structure, genetic diversity and individual response of gene expression in the tree frog Hyla orientalis along a gradient of radioactive contamination around the Chernobyl nuclear power plant. RESULTS: We detected lower effective population size in populations most exposed to ionizing radiation in the Chernobyl Exclusion Zone that is not compensated by migrations from surrounding areas. We also highlighted a decreased body condition of frogs living in the most contaminated area, a distinctive transcriptomics signature and stop-gained mutations in genes involved in energy metabolism. While the association with dose will remain correlational until further experiments, a body of evidence suggests the direct or indirect involvement of radiation exposure in these changes. CONCLUSIONS: Despite ongoing migration and lower total dose rates absorbed than at the time of the accident, our results demonstrate that Hyla orientalis specimens living in the Chernobyl Exclusion Zone are still undergoing deleterious changes, emphasizing the long-term impacts of the nuclear disaster.


Assuntos
Acidente Nuclear de Chernobyl , Animais , Humanos , Densidade Demográfica , Animais Selvagens , Radiação Ionizante , Anuros/genética
3.
Evol Appl ; 15(2): 203-219, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35233243

RESUMO

Despite the ubiquity of pollutants in the environment, their long-term ecological consequences are not always clear and still poorly studied. This is the case concerning the radioactive contamination of the environment following the major nuclear accident at the Chernobyl nuclear power plant. Notwithstanding the implications of evolutionary processes on the population status, few studies concern the evolution of organisms chronically exposed to ionizing radiation in the Chernobyl exclusion zone. Here, we examined genetic markers for 19 populations of Eastern tree frog (Hyla orientalis) sampled in the Chernobyl region about thirty years after the nuclear power plant accident to investigate microevolutionary processes ongoing in local populations. Genetic diversity estimated from nuclear and mitochondrial markers showed an absence of genetic erosion and higher mitochondrial diversity in tree frogs from the Chernobyl exclusion zone compared to other European populations. Moreover, the study of haplotype network permitted us to decipher the presence of an independent recent evolutionary history of Chernobyl exclusion zone's Eastern tree frogs caused by an elevated mutation rate compared to other European populations. By fitting to our data a model of haplotype network evolution, we suspected that Eastern tree frog populations in the Chernobyl exclusion zone have a high mitochondrial mutation rate and small effective population sizes. These data suggest that Eastern tree frog populations might offset the impact of deleterious mutations because of their large clutch size, but also question the long-term impact of ionizing radiation on the status of other species living in the Chernobyl exclusion zone.

4.
Blood Adv ; 4(14): 3217-3223, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32673385

RESUMO

Complete molecular response (CMR) after first-line immunochemotherapy reflects treatment efficacy and may predict prognosis in patients with follicular lymphoma (FL). RELEVANCE is the first phase 3 trial comparing the chemotherapy-free regimen lenalidomide/rituximab (R2) vs rituximab/chemotherapy (R-Chemo) in previously untreated FL patients (ClinicalTrials.gov identifier: NCT01650701). The objective of the minimal residual disease (MRD) analysis was to determine the ability of a chemotherapy-free regimen to induce CMR. Of 440 French patients participating in the Lymphoma Study Association (LYSA) RELEVANCE MRD study, all 222 patients with a BIOMED-2-detectable BCL2-JH translocation at diagnosis were analyzed. MRD was quantified by droplet digital polymerase chain reaction with a sensitivity ≤10-4. At week 24 (end of induction treatment), 98% and 78% of patients achieved CMR in peripheral blood (PB) and bone marrow (BM), respectively. Achievement of CMR (in PB and/or BM) had a significant impact on progression-free survival (PFS), with 3-year PFS of 84% and 55% for patients with CMR and detectable MRD, respectively (P = .015). CMR at week 24 was reached more frequently in the R2 arm (105/117; 90%) than in the R-Chemo arm (70/90; 77%) (P = .022). The poor prognostic value in terms of PFS for the persistence of molecular disease was observed irrespective of treatment arm (interaction test, P = .31). In agreement with the clinical results of the RELEVANCE trial, our results show that R2 immunomodulatory treatment in first-line FL can achieve high rates of CMR.


Assuntos
Linfoma Folicular , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Lenalidomida/uso terapêutico , Linfoma Folicular/tratamento farmacológico , Prognóstico , Rituximab/uso terapêutico
5.
Oncotarget ; 9(29): 20761-20768, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29755687

RESUMO

International guidelines made RAS (KRAS and NRAS) status a prerequisite for the use of anti-EGFR agents for metastatic colorectal cancer (CRC) patients. Daily, new data emerges on the theranostic and prognostic role of molecular biomarkers; this is a strong incentive for a validated, sensitive, and broadly available molecular screening test. Next-generation sequencing (NGS) has begun to supplant other technologies for genomic profiling. We report here our 2 years of clinical practice using NGS results to guide therapeutic decisions. The Ion Torrent AmpliSeq colon/lung cancer panel, which allows mutation detection in 22 cancer-related genes, was prospectively used in clinical practice (BELAC ISO 15189 accredited method). The DNA of 741 formalin-fixed paraffin-embedded CRC tissues, including primary tumors and metastasis, was obtained from 14 different Belgian institutions and subjected to targeted NGS. Of the tumors tested, 98% (727) were successfully sequenced and 89% (650) harbored at least one mutation. KRAS, BRAF and NRAS mutations were found in 335 (46%), 78 (11%) and 32 (4%) samples, respectively. These mutation frequencies were consistent with those reported in public databases. Moreover, mutations and amplifications in potentially actionable genes were identified in 464 samples (64%), including mutations in PIK3CA (14%), ERBB2 (0.4%), AKT1 (0.6%), and MAP2K1 (0.1%), as well as amplifications of ERBB2 (0.3%) and EGFR (0.3%). The median turnaround time between reception of the sample in the laboratory and report release was 8 calendar days. Overall, the AmpliSeq colon/lung cancer panel was successfully applied in daily practice and provided reliable clinically relevant information for CRC patients.

6.
C R Biol ; 341(2): 75-84, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29402590

RESUMO

Euryhaline Cichlid fish of the species Coptodon guineensis are present in different water holes situated in a dried depression in the desert in the extreme South of Morocco, the Sebkha of Imlili. A genetic survey of this population, using complete sequences of the ND2 gene (mtDNA) and sixteen microsatellite loci, revealed that the fish in the sebkha did not form a single population, but rather a metapopulation. This metapopulational structure may be regarded as good news from the point of view of the conservation of fish in the sebkha. Although small individual populations may have short, finite life spans, the metapopulation as a whole is more stable, because immigrants from one population are likely to re-colonize the habitat, left open by the extinction of another.


Assuntos
Ciclídeos/genética , DNA Mitocondrial/genética , Animais , Ecossistema , Meio Ambiente , Repetições de Microssatélites , Marrocos , Dinâmica Populacional
7.
Microb Ecol ; 75(3): 799-810, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28956100

RESUMO

Understanding the role of microbiota as reproductive barriers or sources of adaptive novelty in the fundamental biological phenomenon of speciation is an exciting new challenge necessitating exploration of microbiota variation in wild interbreeding species. We focused on two interbreeding cyprinid species, Chondrostoma nasus and Parachondrostoma toxostoma, which have geographic distributions characterized by a mosaic of hybrid zones. We described microbiota diversity and composition in the three main teleost mucosal tissues, the skin, gills and gut, in the parental parapatric populations. We found that tissue type was the principal determinant of bacterial community composition. In particular, there was strong microbiota differentiation between external and internal tissues, with secondary discrimination between the two species. These findings suggest that specific environmental and genetic filters associated with each species have shaped the bacterial communities, potentially reflecting deterministic assemblages of bacteria. We defined the core microbiota common to both Chondrostoma species for each tissue, highlighting the occurrence of microbe-host genome interactions at this critical level for studies of the functional consequences of hybridization. Further investigations will explore to what extend these specific tissue-associated microbiota signatures could be profoundly altered in hybrids, with functional consequences for post-mating reproductive isolation in relation to environmental constraints.


Assuntos
Bactérias/classificação , Biodiversidade , Cyprinidae/microbiologia , Microbiota/fisiologia , Filogenia , Animais , Bactérias/genética , DNA Bacteriano , Feminino , França , Microbioma Gastrointestinal , Brânquias/microbiologia , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Especificidade de Hospedeiro , Hibridização Genética , Masculino , Microbiota/genética , Mucosa/microbiologia , Pele/microbiologia
8.
PLoS One ; 12(9): e0185020, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28931057

RESUMO

Analyses of high-throughput transcriptome sequences of non-model organisms are based on two main approaches: de novo assembly and genome-guided assembly using mapping to assign reads prior to assembly. Given the limits of mapping reads to a reference when it is highly divergent, as is frequently the case for non-model species, we evaluate whether using blastn would outperform mapping methods for read assignment in such situations (>15% divergence). We demonstrate its high performance by using simulated reads of lengths corresponding to those generated by the most common sequencing platforms, and over a realistic range of genetic divergence (0% to 30% divergence). Here we focus on gene identification and not on resolving the whole set of transcripts (i.e. the complete transcriptome). For simulated datasets, the transcriptome-guided assembly based on blastn recovers 94.8% of genes irrespective of read length at 0% divergence; however, assignment rate of reads is negatively correlated with both increasing divergence level and reducing read lengths. Nevertheless, we still observe 92.6% of recovered genes at 30% divergence irrespective of read length. This analysis also produces a categorization of genes relative to their assignment, and suggests guidelines for data processing prior to analyses of comparative transcriptomics and gene expression to minimize potential inferential bias associated with incorrect transcript assignment. We also compare the performances of de novo assembly alone vs in combination with a transcriptome-guided assembly based on blastn both via simulation and empirically, using data from a cyprinid fish species and from an oak species. For any simulated scenario, the transcriptome-guided assembly using blastn outperforms the de novo approach alone, including when the divergence level is beyond the reach of traditional mapping methods. Combining de novo assembly and a related reference transcriptome for read assignment also addresses the bias/error in contigs caused by the dependence on a related reference alone. Empirical data corroborate these findings when assembling transcriptomes from the two non-model organisms: Parachondrostoma toxostoma (fish) and Quercus pubescens (plant). For the fish species, out of the 31,944 genes known from D. rerio, the guided and de novo assemblies recover respectively 20,605 and 20,032 genes but the performance of the guided assembly approach is much higher for both the contiguity and completeness metrics. For the oak, out of the 29,971 genes known from Vitis vinifera, the transcriptome-guided and de novo assemblies display similar performance, but the new guided approach detects 16,326 genes where the de novo assembly only detects 9,385 genes.


Assuntos
Biologia Computacional/métodos , Peixes/genética , Perfilação da Expressão Gênica , Quercus/genética , Análise de Sequência de DNA/métodos , Transcriptoma , Peixe-Zebra/genética , Animais , Mapeamento de Sequências Contíguas , Genoma , Genômica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Modelos Estatísticos , Anotação de Sequência Molecular
10.
PLoS One ; 10(11): e0142592, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26561027

RESUMO

Understanding the impact of non-native species on native species is a major challenge in molecular ecology, particularly for genetically compatible fish species. Invasions are generally difficult to study because their effects may be confused with those of environmental or human disturbances. Colonized ecosystems are differently impacted by human activities, resulting in diverse responses and interactions between native and non-native species. We studied the dynamics between two Cyprinids species (invasive Chondrostoma nasus and endemic Parachondrostoma toxostoma) and their hybrids in 16 populations (from allopatric to sympatric situations and from little to highly fragmented areas) corresponding to 2,256 specimens. Each specimen was assigned to a particular species or to a hybrid pool using molecular identification (cytochrome b and 41 microsatellites). We carried out an ecomorphological analysis based on size, age, body shape, and diet (gut vacuity and molecular fecal contents). Our results contradicted our initial assumptions on the pattern of invasion and the rate of introgression. There was no sign of underperformance for the endemic species in areas where hybridisation occurred. In the unfragmented zone, the introduced species was found mostly downstream, with body shapes similar to those in allopatric populations while both species were found to be more insectivorous than the reference populations. However, high level of hybridisation was detected, suggesting interactions between the two species during spawning and/or the existence of hybrid swarm. In the disturbed zone, introgression was less frequent and slender body shape was associated with diatomivorous behaviour, smaller size (juvenile characteristics) and greater gut vacuity. Results suggested that habitat degradation induced similar ecomorphological trait changes in the two species and their hybrids (i.e. a transition towards a pedomorphic state) where the invasive species is more affected than the native species. Therefore, this study reveals a diversity of relationships between two genetically compatible species and emphasizes constraints on the invasion process in disturbed areas.


Assuntos
Cyprinidae/fisiologia , Ecossistema , Espécies Introduzidas , Rios , Algoritmos , Animais , Tamanho Corporal , Conservação dos Recursos Naturais , Citocromos b/genética , Dieta , Comportamento Alimentar , França , Geografia , Hibridização Genética , Repetições de Microssatélites/genética , Especificidade da Espécie , Temperatura
11.
Aquat Toxicol ; 169: 113-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26523677

RESUMO

This work aims to explore in the field the relationship between the integrity of sperm DNA and the quality of offspring as a possible cause of the decline of a feral fish population through reproduction impairment. Mature nase (Chondrostoma nasus) were caught during the breeding season in three locations (A-C) of the Rhône River basin and gametes collected by stripping. Sampling locations were chosen according to the following gradient of contamination due to human activities on the watershed: A≤B

Assuntos
Cyprinidae/fisiologia , Reprodução/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Cyprinidae/genética , Dano ao DNA , Embrião não Mamífero , Masculino , Rios/química , Espermatozoides/patologia
12.
Hematology ; 20(3): 129-36, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25029908

RESUMO

OBJECTIVES: The randomized phase 3 PRIMA trial established that 2 years of rituximab maintenance therapy after attaining disease response to immunochemotherapy as first-line treatment of follicular lymphoma, reduced the risk of disease progression, compared with observation, without adversely affecting patient-reported quality of life (QoL). We now report additional analyses of symptom burden and toxicity. METHODS: Symptom burden was measured by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 items. The proportion of patients with worsening, no change, or improvement in symptoms from maintenance baseline was compared between rituximab maintenance and observation groups with Pearson χ(2) tests. Improvement in symptoms after 1 and 2 years of maintenance was further analyzed using generalized mixed models. The adverse event (AE) rate was calculated from the toxicity checklist at each visit to explore the frequency and timing of the toxicity AE in each treatment arm. The study protocol was approved by local ethics committees and is registered at ClinicalTrials.gov under NCT00140582. RESULTS: Being tired, needing to rest, feeling weak, and trouble sleeping were the most frequently reported symptoms at the end of immunochemotherapy. By the end of maintenance, notable improvement was seen for fatigue symptoms, trouble sleeping, shortness of breath, lack of appetite, and nausea, with no significant difference in QoL symptoms between the rituximab maintenance and observation groups. The rate of AEs was low, and hematologic toxicity induced during chemotherapy treatment improved in both rituximab maintenance and observation groups. DISCUSSION: These results indicated that rituximab maintenance did not negatively impact disease- or treatment-related symptoms.


Assuntos
Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Linfoma Folicular/diagnóstico , Linfoma Folicular/terapia , Rituximab/efeitos adversos , Rituximab/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Feminino , Humanos , Imunoterapia , Quimioterapia de Manutenção , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Qualidade de Vida , Inquéritos e Questionários , Adulto Jovem
13.
Front Zool ; 11(1): 84, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25473413

RESUMO

BACKGROUND: Chaetognatha are a phylum of marine carnivorous animals which includes more than 130 extant species. The internal systematics of this group have been intensively debated since it was discovered in the 18(th) century. While they can be traced back to the earlier Cambrian, they are an extraordinarily homogeneous phylum at the morphological level - a fascinating characteristic that puzzled many a scientist who has tried to clarify their taxonomy. Recent studies which have attempted to reconstruct a phylogeny using molecular data have relied on single gene analyses and a somewhat restricted taxon sampling. Here, we present the first large scale phylogenetic study of Chaetognatha based on a combined analysis of nearly the complete ribosomal RNA (rRNA) genes. We use this analysis to infer the evolution of some morphological characters. This work includes 36 extant species, mainly obtained from Tara Oceans Expedition 2009/2012, that represent 16 genera and 6 of the 9 extant families. RESULTS: Cladistic and phenetic analysis of morphological characters, geometric morphometrics and molecular small subunit (SSU rRNA) and large subunit (LSU rRNA) ribosomal genes phylogenies provided new insights into the relationships and the evolutionary history of Chaetognatha. We propose the following clade structure for the phylum: (((Sagittidae, Krohnittidae), Spadellidae), (Eukrohniidae, Heterokrohniidae)), with the Pterosagittidae included in the Sagittidae. The clade (Sagittidae, Krohnittidae) constitutes the monophyletic order of Aphragmophora. Molecular analyses showed that the Phragmophora are paraphyletic. The Ctenodontina/Flabellodontina and Syngonata/Chorismogonata hypotheses are invalidated on the basis of both morphological and molecular data. This new phylogeny also includes resurrected and modified genera within Sagittidae. CONCLUSIONS: The distribution of some morphological characters traditionally used in systematics and for species diagnosis suggests that the diversity in Chaetognatha was produced through a process of mosaic evolution. Moreover, chaetognaths have mostly evolved by simplification of their body plan and their history shows numerous convergent events of losses and reversions. The main morphological novelty observed is the acquisition of a second pair of lateral fins in Sagittidae, which represents an adaptation to the holoplanktonic niche.

14.
Mol Ecol Resour ; 14(6): 1302-13, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24785154

RESUMO

Microsatellite marker development has been greatly simplified by the use of high-throughput sequencing followed by in silico microsatellite detection and primer design. However, the selection of markers designed by the existing pipelines depends either on arbitrary criteria, or older studies on PCR success. Based on wet laboratory experiments, we have identified the following factors that are most likely to influence genotyping success rate: alignment score between the primers and the amplicon; the distance between primers and microsatellites; the length of the PCR product; target region complexity and the number of reads underlying the sequence. The QDD pipeline has been modified to include these most pertinent factors in the output to help the selection of markers. Furthermore, new features are also included in the present version: (i) not only raw sequencing reads are accepted as input, but also contigs, allowing the analysis of assembled high-coverage data; (ii) input data can be both in fasta and fastq format to facilitate the use of Illumina and IonTorrent reads; (iii) A comparison to known transposable elements allows their detection; (iv) A contamination check can be carried out by BLASTing potential markers against the nucleotide (nt) database of NCBI; (v) QDD3 is now also available imbedded into a virtual machine making installation easier and operating system independent. It can be used both on command-line version as well as integrated into a Galaxy server, providing a user-friendly interface, as well as the possibility to utilize a large variety of NGS tools.


Assuntos
Técnicas de Genotipagem/métodos , Repetições de Microssatélites , Software , Animais , Cyprinidae/classificação , Cyprinidae/genética , Primers do DNA/genética , Dados de Sequência Molecular , Análise de Sequência de DNA
15.
J Clin Oncol ; 31(23): 2912-9, 2013 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-23835718

RESUMO

PURPOSE: Obinutuzumab (GA101), a type II, glycoengineered, humanized anti-CD20 monoclonal antibody, was superior to rituximab in human diffuse large B-cell lymphoma (DLBCL) and mantle-cell lymphoma (MCL) xenograft models. In phase I of our study, obinutuzumab (GA101) exhibited encouraging activity but no clear dose-response relationship, and few patients had aggressive histologies. The efficacy and safety of two doses of obinutuzumab (GA101) were explored in our randomized phase II trial in patients with heavily pretreated DBLCL and MCL. PATIENTS AND METHODS: Patients were randomly assigned to receive eight cycles of obinutuzumab (GA101) either as a flat dose of 400 mg for all infusions (days 1 and 8 of cycle 1; day 1 of cycles 2 to 8) or 1,600 mg on days 1 and 8 of cycle 1 and 800 mg on day 1 of cycles 2 to 8. RESULTS: Forty patients were enrolled: 21 patients in the 400/400-mg treatment arm (DLBCL, n = 10; MCL, n = 11) and 19 patients in the 1,600/800-mg arm (DLBCL, n = 15; MCL, n = 4). End-of-treatment response was 28% (32% and 24% in the 1,600/800-mg and 400/400-mg study arms, respectively). Best overall response rates were 37% in the 1,600/800-mg arm and 24% in the 400/400-mg study arm (DLBCL, eight [32%] of 25 patients; MCL, four [27%] of 15 patients). Five (20%) of 25 rituximab-refractory patients exhibited treatment response, including four of 12 in the 1,600/800-mg group. The most common adverse events were infusion-related reactions (IRRs), which were manageable. Three patients had grade 3/4 IRRs. Grade 3/4 neutropenia was seen in only one patient. CONCLUSION: Obinutuzumab (GA101) 1,600/800 mg achieves early steady-state concentration and clinical activity with an acceptable safety profile in relapsed/refractory DLBCL and MCL, supporting further exploration.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Antineoplásicos/administração & dosagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma de Célula do Manto/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacocinética , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Esquema de Medicação , Feminino , Humanos , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma de Célula do Manto/metabolismo , Masculino , Pessoa de Meia-Idade
16.
PLoS One ; 8(6): e65883, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23824831

RESUMO

Two cyprinid species, Parachondrostoma toxostoma, an endemic threatened species, and Chondrostoma nasus, an invasive species, live in sympatry in southern France and form two sympatric zones where the presence of intergeneric hybrids is reported. To estimate the potential threat to endemic species linked to the introduction of invasive species, we focused on the DAB genes (functional MHC IIB genes) because of their adaptive significance and role in parasite resistance. More specifically, we investigated (1) the variability of MHC IIB genes, (2) the selection pattern shaping MHC polymorphism, and (3) the extent to which trans-species evolution and intergeneric hybridization affect MHC polymorphism. In sympatric areas, the native species has more diversified MHC IIB genes when compared to the invasive species, probably resulting from the different origins and dispersal of both species. A similar level of MHC polymorphism was found at population level in both species, suggesting similar mechanisms generating MHC diversity. In contrast, a higher number of DAB-like alleles per specimen were found in invasive species. Invasive species tended to express the alleles of two DAB lineages, whilst native species tended to express the alleles of only the DAB3 lineage. Hybrids have a pattern of MHC expression intermediate between both species. Whilst positive selection acting on peptide binding sites (PBS) was demonstrated in both species, a slightly higher number of positively selected sites were identified in C. nasus, which could result from parasite-mediated selection. Bayesian clustering analysis revealed a similar pattern of structuring for the genetic variation when using microsatellites or the MHC approach. We confirmed the importance of trans-species evolution for MHC polymorphism. In addition, we demonstrated bidirectional gene flow for MHC IIB genes in sympatric areas. The positive significant correlation between MHC and microsatellites suggests that demographic factors may contribute to MHC variation on a short time scale.


Assuntos
Cyprinidae/genética , Espécies em Perigo de Extinção , Evolução Molecular , Genes MHC da Classe II , Alelos , Animais , Teorema de Bayes , Cyprinidae/classificação , Espécies Introduzidas , Filogenia , Polimorfismo Genético , Recombinação Genética
17.
Front Zool ; 10(1): 22, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23634901

RESUMO

INTRODUCTION: Hybridization is a common phenomenon in fish and is considered to be a major source of diversification. Deciphering the remoulding of genomic regions and phenotypes in zones where hybrid specimens occur is of particular interest to elucidate the emergence of evolutionary novelties. This approach is particularly challenging because the first step of hybridization seems to be the most important stage in the emergence of hybrid lineages. However, the signal can be significantly altered after only a few generations. RESULTS: We studied 41 microsatellites and partial cytochrome b gene sequences in 970 specimens belonging to two fish species (Chondrostoma nasus and Parachondrostoma toxostoma) in allopatric/parapatric zones, hybrids between them in a natural sympatric zone: the Ardèche basin. We showed that the genomic architecture in hybrids presented pattern heterogeneity of selection for the different loci. Indeed, the upstream part of the river (Rosières and Labeaume) presented an overdominant fitness of heterozygotes (12.20%) corresponding to a genomic compatibility, and underselection was observed for 4.88%-7.32% of the loci tested indicating a genomic incompatibility. Moreover the upstream station (Rosières) presented a positive selection of invasive C. nasus homozygotes (17.07% to 21.95%) indicating that hybridization may increase the fitness of admixed individuals.We showed that hybrid morphology (body shape based on 21 landmarks) correlated with genomic dilution indicating a species fingerprint. However, we demonstrated that the hybrid morphology was not a linear modification between the two parental species but a trade-off between several correlated traits. CONCLUSIONS: Hybrid specimens present a mosaic of genomic combination, showing regions with genomic compatibility and others with genomic incompatibility between the two species. Positive selection (invasive advantage ranging from 9.76% to 21.95% of the loci) was evidenced in the upstream part of the Ardèche indicating that environmental selection makes a substantial contribution. Although the presence of a dam is known to impose heterogeneous hybrid zones between these two species, we demonstrated in this study that a natural environment can also generate a hybrid zone with a large number (and diversity) of hybrids. The combination of the two genomes in the hybrids results in complex ontogenetic trajectories (with different morphological traits evolving at different rates) that correspond to novel developmental pathways.

18.
Oncol Rep ; 30(1): 371-6, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23603900

RESUMO

We investigated the prevalence of human papillomavirus (HPV) in a clinical series of 72 patients with head and neck squamous cell carcinoma (HNSCC) using a retrospective and prospective study design. The majority of patients were smokers and/or drinkers and were treated with concomitant chemoradiotherapy (CCR). Furthermore, we assessed the impact of HPV positivity on the response to CCR. Paraffin-embedded samples from HNSCC patients (n=72) were evaluated for the presence of HPV DNA using both GP5+/GP6+ consensus PCR and type-specific E6/E7 PCR to detect HPV types 6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 67 and 68. The type-specific E6/E7 PCR demonstrated that 20 out of 69 HNSCC patients (29%) presented with high-risk (HR) HPV types and that 5 of the 69 HNSCC patients (7%) presented with low-risk (LR) HPV types. Using the GP5+/GP6+ PCR, we observed that the rate of response was statistically lower in the HPV+ group (P=0.02). Concerning patient outcomes in terms of recurrence and survival, we observed that the prognosis was poorer for HPV+ patients. We showed for the first time that patients with HPV+ HNSCC present with a worse prognosis after CCR. This observation highlights the need for prospective studies with large numbers of patients and a detailed history of tobacco and alcohol consumption before validating HPV as a marker of prognosis following CCR.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Infecções por Papillomavirus/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Carboplatina/uso terapêutico , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/virologia , Cetuximab , Quimiorradioterapia , Cisplatino/uso terapêutico , DNA Viral/análise , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Papillomaviridae , Infecções por Papillomavirus/virologia , Estudos Prospectivos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Taxa de Sobrevida , Resultado do Tratamento
19.
PLoS One ; 8(4): e59439, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23593138

RESUMO

Thecosomata is a marine zooplankton group, which played an important role in the carbonate cycle in oceans due to their shell composition. So far, there is important discrepancy between the previous morphological-based taxonomies, and subsequently the evolutionary history of Thecosomata. In this study, the remarkable planktonic sampling of TARA Oceans expedition associated with a set of various other missions allowed us to assess the phylogenetic relationships of Thecosomata using morphological and molecular data (28 S and COI genes). The two gene trees showed incongruities (e.g. Hyalocylis, Cavolinia), and high congruence between morphological and 28S trees (e.g. monophyly of Euthecosomata). The monophyly of straight shell species led us to reviving the Orthoconcha, and the split of Limacinidae led us to the revival of Embolus inflata replacing Limacina inflata. The results also jeopardized the Euthecosomata families that are based on plesiomorphic character state as in the case for Creseidae which was not a monophyletic group. Divergence times were also estimated, and suggested that the evolutionary history of Thecosomata was characterized by four major diversifying events. By bringing the knowledge of palaeontology, we propose a new evolutionary scenario for which macro-evolution implying morphological innovations were rhythmed by climatic changes and associated species turn-over that spread from the Eocene to Miocene, and were shaped principally by predation and shell buoyancy.


Assuntos
Gastrópodes/anatomia & histologia , Gastrópodes/classificação , Filogenia , Animais , Teorema de Bayes , Bases de Dados Genéticas , Complexo IV da Cadeia de Transporte de Elétrons/genética , Evolução Molecular , RNA Ribossômico 28S/genética
20.
Leuk Lymphoma ; 54(9): 1898-907, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23327290

RESUMO

Elevated serum free light chains (FLCs) have been associated with an unfavorable prognosis in diffuse large B-cell lymphoma (DLBCL). The aim of this study was to determine the clinical relevance of a quantitative assessment of intact circulating immunoglobulin (Ig), using serum Ig heavy chain/light chain pair (HLC) measurements in patients with DLBCL. FLC and HLC were measured in 409 serum samples of patients with DLBCL included in the LNH03-B clinical trial program of the Groupe d'Etudes des Lymphomes de l'Adulte (GELA). Patients with an abnormal IgMκ/IgMλ ratio or an abnormal FLC ratio more frequently displayed adverse clinical characteristics. Patients with abnormal IgMκ/IgMλ ratios had inferior progression-free survival (PFS) and overall survival (OS) as compared to patients with a normal ratio in the overall cohort (5-year PFS 44.9% vs. 69.3%, p = 0.0003 and 5-year OS 50.8% vs. 78.1%, p = 0.0003) and in the R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) cohort (5-year OS 43.5% vs. 70.3%, p = 0.003). In multivariate analysis, including elevated FLC/HLC and International Prognostic Index (IPI), an abnormal IgMκ/IgMλ ratio (hazard ratio [HR] = 1.54, 95% confidence interval [CI] 1.03-2.3, p = 0.03) remained predictive of shorter progression-free survival. Gene expression profile experiments and immunohistochemistry indicate that this measurement is at least partially related to tumor cell secretion. Both elevated serum FLCs and an abnormal IgMκ/IgMλ ratio are associated with unfavorable outcomes in patients with DLBCL treated by R-CHOP.


Assuntos
Cadeias Pesadas de Imunoglobulinas/sangue , Cadeias Leves de Imunoglobulina/sangue , Linfoma Difuso de Grandes Células B/sangue , Linfoma Difuso de Grandes Células B/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Feminino , Humanos , Isotipos de Imunoglobulinas/sangue , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Prognóstico , Modelos de Riscos Proporcionais , Rituximab , Vincristina/uso terapêutico
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