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1.
J Neurooncol ; 165(3): 413-430, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38095774

RESUMO

BACKGROUND AND OBJECTIVES: Tumor location and eloquence are two crucial preoperative factors when deciding on the optimal treatment choice in glioma management. Consensus is currently lacking regarding the preoperative assessment and definition of eloquent areas. This systematic review aims to evaluate the existing definitions and assessment methods of eloquent areas that are used in current clinical practice. METHODS: A computer-aided search of Embase, Medline (OvidSP), and Google Scholar was performed to identify relevant studies. This review includes articles describing preoperative definitions of eloquence in the study's Methods section. These definitions were compared and categorized by anatomical structure. Additionally, various techniques to preoperatively assess tumor eloquence were extracted, along with their benefits, drawbacks and ease of use. RESULTS: This review covers 98 articles including 12,714 participants. Evaluation of these studies indicated considerable variability in defining eloquence. Categorization of these definitions yielded a list of 32 brain regions that were considered eloquent. The most commonly used methods to preoperatively determine tumor eloquence were anatomical classification systems and structural MRI, followed by DTI-FT, functional MRI and nTMS. CONCLUSIONS: There were major differences in the definitions and assessment methods of eloquence, and none of them proved to be satisfactory to express eloquence as an objective, quantifiable, preoperative factor to use in glioma decision making. Therefore, we propose the development of a novel, objective, reliable, preoperative classification system to assess eloquence. This should in the future aid neurosurgeons in their preoperative decision making to facilitate personalized treatment paradigms and to improve surgical outcomes.


Assuntos
Neoplasias Encefálicas , Glioma , Neurocirurgia , Humanos , Mapeamento Encefálico/métodos , Imagem de Tensor de Difusão/métodos , Encéfalo/cirurgia , Glioma/diagnóstico por imagem , Glioma/cirurgia , Neoplasias Encefálicas/cirurgia
2.
J Magn Reson ; 356: 107561, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37837749

RESUMO

We report here instrumental developments to achieve sustainable, cost-effective cryogenic Helium sample spinning in order to conduct dynamic nuclear polarisation (DNP) and solid-state NMR (ssNMR) at ultra-low temperatures (<30 K). More specifically, we describe an efficient closed-loop helium system composed of a powerful heat exchanger (95% efficient), a single cryocooler, and a single helium compressor to power the sample spinning and cooling. The system is integrated with a newly designed triple-channel NMR probe that minimizes thermal losses without compromising the radio frequency (RF) performance and spinning stability (±0.05%). The probe is equipped with an innovative cryogenic sample exchange system that allows swapping samples in minutes without introducing impurities in the closeloop system. We report that significant gain in sensitivity can be obtained at 30-40 K on large micro-crystalline molecules with unfavorable relaxation timescales, making them difficult or impossible to polarize at 100 K. We also report rotor-synchronized 2D experiments to demonstrate the stability of the system.

3.
Sci Rep ; 13(1): 25, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36646720

RESUMO

Small airway remodeling (SAR) is a key phenomenon of airflow obstruction in smokers, leading to chronic obstructive pulmonary disease (COPD). SAR results in an increased thickness of small airway walls, with a combination of peribronchiolar fibrosis with increased fibrous tissue and accumulation of mesenchymal and epithelial cells. SAR pathogenesis is still unclear but recent data suggest that alterations in telomerase activity could represent a possible underlying mechanism of SAR. Our study was dedicated to identify a potential protective role of TA-65, a pharmacological telomerase activator, in a cigarette smoke (CS) model of SAR in mice, and to further precise if extra-telomeric effects of telomerase, involving oxidative stress modulation, could explain it. C57BL/6J mice were daily exposed to air or CS during 4 weeks with or without a concomitant administration of TA-65 starting 7 days before CS exposure. Morphological analyses were performed, and mucus production, myofibroblast differentiation, collagen deposition, as well as transforming growth factor-ß1 (TGF-ß1) expression in the small airway walls were examined. In addition, the effects of TA-65 treatment on TGF-ß expression, fibroblast-to-myofibroblast differentiation, reactive oxygen species (ROS) production and catalase expression and activity were evaluated in primary cultures of pulmonary fibroblasts and/or mouse embryonic fibroblasts in vitro. Exposure to CS during 4 weeks induced SAR in mice, characterized by small airway walls thickening and peribronchiolar fibrosis (increased deposition of collagen, expression of α-SMA in small airway walls), without mucus overproduction. Treatment of mice with TA-65 protected them from CS-induced SAR. This effect was associated with the prevention of CS-induced TGF-ß expression in vivo, the blockade of TGF-ß-induced myofibroblast differentiation, and the reduction of TGF-ß-induced ROS production that correlates with an increase of catalase expression and activity. Our findings demonstrate that telomerase is a critical player of SAR, probably through extra-telomeric anti-oxidant effects, and therefore provide new insights in the understanding and treatment of COPD pathogenesis.


Assuntos
Fumar Cigarros , Doença Pulmonar Obstrutiva Crônica , Telomerase , Camundongos , Animais , Catalase/metabolismo , Telomerase/metabolismo , Remodelação das Vias Aéreas , Fumar Cigarros/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Camundongos Endogâmicos C57BL , Fibroblastos/metabolismo , Doença Pulmonar Obstrutiva Crônica/etiologia , Colágeno/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fibrose
4.
PLoS One ; 17(12): e0278864, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36512593

RESUMO

BACKGROUND: Glioblastomas are mostly resected under general anesthesia under the supervision of a general anesthesiologist. Currently, it is largely unkown if clinical outcomes of GBM patients can be improved by appointing a neuro-anesthesiologist for their cases. We aimed to evaluate whether the assignment of dedicated neuro-anesthesiologists improves the outcomes of these patients. We also investigated the value of dedicated neuro-oncological surgical teams as an independent variable in both groups. METHODS: A cohort consisting of 401 GBM patients who had undergone resection was retrospectively investigated. Primary outcomes were postoperative neurological complications, fluid balance, length-of-stay and overall survival. Secondary outcomes were blood loss, anesthesia modality, extent of resection, total admission costs, and duration of surgery. RESULTS: 320 versus 81 patients were operated under the anesthesiological supervision of a general anesthesiologist and a dedicated neuro-anesthesiologist, respectively. Dedicated neuro-anesthesiologists yielded significant superior outcomes in 1) postoperative neurological complications (early: p = 0.002, OR = 2.54; late: p = 0.003, OR = 2.24); 2) fluid balance (p<0.0001); 3) length-of-stay (p = 0.0006) and 4) total admission costs (p = 0.0006). In a subanalysis of the GBM resections performed by an oncological neurosurgeon (n = 231), the assignment of a dedicated neuro-anesthesiologist independently improved postoperative neurological complications (early minor: p = 0.0162; early major: p = 0.00780; late minor: p = 0.00250; late major: p = 0.0364). The assignment of a dedicated neuro-oncological team improved extent of resection additionally (p = 0.0416). CONCLUSION: GBM resections with anesthesiological supervision of a dedicated neuro-anesthesiologists are associated with improved patient outcomes. Prospective evidence is needed to further investigate the usefulness of the dedicated neuro-anesthesiologist in different settings.


Assuntos
Glioblastoma , Humanos , Glioblastoma/cirurgia , Estudos de Coortes , Estudos Retrospectivos , Estudos Prospectivos , Anestesia Geral , Complicações Pós-Operatórias
5.
Neurooncol Pract ; 9(5): 364-379, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36127890

RESUMO

One of the major challenges during glioblastoma surgery is balancing between maximizing extent of resection and preventing neurological deficits. Several surgical techniques and adjuncts have been developed to help identify eloquent areas both preoperatively (fMRI, nTMS, MEG, DTI) and intraoperatively (imaging (ultrasound, iMRI), electrostimulation (mapping), cerebral perfusion measurements (fUS)), and visualization (5-ALA, fluoresceine)). In this review, we give an update of the state-of-the-art management of both primary and recurrent glioblastomas. We will review the latest surgical advances, challenges, and approaches that define the onco-neurosurgical practice in a contemporary setting and give an overview of the current prospective scientific efforts.

6.
BMJ Open ; 11(7): e047306, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290067

RESUMO

INTRODUCTION: The main surgical dilemma during glioma resections is the surgeon's inability to accurately identify eloquent areas when the patient is under general anaesthesia without mapping techniques. Intraoperative stimulation mapping (ISM) techniques can be used to maximise extent of resection in eloquent areas yet simultaneously minimise the risk of postoperative neurological deficits. ISM has been widely implemented for low-grade glioma resections backed with ample scientific evidence, but this is not yet the case for high-grade glioma (HGG) resections. Therefore, ISM could thus be of important value in HGG surgery to improve both surgical and clinical outcomes. METHODS AND ANALYSIS: This study is an international, multicenter, prospective three-arm cohort study of observational nature. Consecutive HGG patients will be operated with awake mapping, asleep mapping or no mapping with a 1:1:1 ratio. Primary endpoints are: (1) proportion of patients with National Institute of Health Stroke Scale deterioration at 6 weeks, 3 months and 6 months after surgery and (2) residual tumour volume of the contrast-enhancing and non-contrast-enhancing part as assessed by a neuroradiologist on postoperative contrast MRI scans. Secondary endpoints are: (1) overall survival and (2) progression-free survival at 12 months after surgery; (3) oncofunctional outcome and (4) frequency and severity of serious adverse events in each arm. Total duration of the study is 5 years. Patient inclusion is 4 years, follow-up is 1 year. ETHICS AND DISSEMINATION: The study has been approved by the Medical Ethics Committee (METC Zuid-West Holland/Erasmus Medical Center; MEC-2020-0812). The results will be published in peer-reviewed academic journals and disseminated to patient organisations and media. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov ID number NCT04708171 (PROGRAM-study), NCT03861299 (SAFE-trial).


Assuntos
Neoplasias Encefálicas , Glioma , Mapeamento Encefálico , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Estudos de Coortes , Glioma/diagnóstico por imagem , Glioma/cirurgia , Humanos , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto , Estudos Prospectivos , Vigília
8.
Heredity (Edinb) ; 124(2): 336-350, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31541203

RESUMO

Species' geographical ranges are often restricted due to niche limitation resulting in geographical isolation and reduced population size at range margins. Under the "abundant center" paradigm, static marginal populations are thus expected to show higher genetic differentiation and lower genetic diversity than core populations. Low mate availability may also drive shifts toward higher propensity for selfing in geographically marginal populations. However, these predictions remain to be validated for contemporary range shifts occurring under current environmental change. This study is devoted to bridging this gap and assesses the spatial patterns of genetic structure and mating system across the geographical range of two coastal plant species characterized by contrasting contemporary range dynamics: the receding myrmecochorous Dune pansy (Viola tricolor subsp. curtisii) and the widespread expanding hydrochorous Rock samphire (Crithmum maritimum). Both species exhibited high propensity for selfing, with indications of inbreeding depression acting at early life stages. In Dune pansy, a biogeographical break was observed between core and marginal populations, with trailing-edge populations showing higher levels of genetic differentiation, reduced genetic diversity, and higher levels of selfing estimated through progeny arrays. In contrast, genetic structuring was weak in Rock samphire and no clear spatial trends were observed in genetic diversity nor in mating system, likely the result of efficient long-distance seed dispersal by sea-surface currents. Our study highlights that key species differences in life-history traits related to dispersal and/or mate limitation modify the expectations of genetic diversity loss and mating system shift in contemporary range-expanding populations, as compared with historical core populations.


Assuntos
Apiaceae/genética , Variação Genética , Genética Populacional , Viola/genética , Ecossistema , Europa (Continente) , Geografia , Depressão por Endogamia , Repetições de Microssatélites , Filogeografia , Densidade Demográfica , Reprodução
9.
Acta Neurochir (Wien) ; 161(2): 307-315, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30617715

RESUMO

BACKGROUND: Awake craniotomy with electrocortical and subcortical mapping (AC) has become the mainstay of surgical treatment of supratentorial low-grade gliomas in eloquent areas, but not as much for glioblastomas. OBJECTIVE: This retrospective controlled-matched study aims to determine whether AC increases gross total resections (GTR) and decreases neurological morbidity in glioblastoma patients as compared to resection under general anesthesia (GA, conventional). METHODS: Thirty-seven patients with glioblastoma undergoing AC were 1:3 controlled-matched with 111 patients undergoing GA for glioblastoma resection. The two groups were matched for age, gender, preoperative Karnofsky Performance Score (KPS), preoperative tumor volume, tumor location, and type of adjuvant treatment. Primary outcomes were extent of resection and the rate of postoperative complications. The secondary outcome was overall postoperative survival. RESULTS: After matching, there were no significant differences in clinical variables between groups. Extent of resection was significantly higher in the AC group: mean extent of resection in the AC group was 94.89% (SD = 10.57) as compared to 70.30% (SD = 28.37) in the GA group (p = 0.0001). Furthermore, the mean rate of late minor postoperative complications in the AC group (0.03; SD = - 0.16) was significantly lower than in the GA group (0.15; SD = 0.39) (p = 0.05). No significant differences between groups were found for the other subgroups of postoperative complications. Moreover, overall postoperative survival did not differ between groups (p = 0.297). CONCLUSION: These findings suggest that resection of glioblastoma using AC is associated with significantly greater extent of resection and less late minor postoperative complications as compared with craniotomy under GA without the use of surgery adjuncts. However, due to certain limitations inherent to our study design (selection bias) and the absence of the use of surgery adjuncts in the GA group, we advocate for a prospective study to further build upon this evidence and study the use of AC in glioblastoma patients.


Assuntos
Anestesia Geral/efeitos adversos , Neoplasias Encefálicas/cirurgia , Craniotomia/métodos , Glioblastoma/cirurgia , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Craniotomia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Acta Neurochir (Wien) ; 161(1): 99-107, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30465276

RESUMO

BACKGROUND: Intraoperative stimulation mapping (ISM) using electrocortical mapping (awake craniotomy, AC) or evoked potentials has become a solid option for the resection of supratentorial low-grade gliomas in eloquent areas, but not as much for high-grade gliomas. This meta-analysis aims to determine whether the surgeon, when using ISM and AC, is able to achieve improved overall survival and decreased neurological morbidity in patients with high-grade glioma as compared to resection under general anesthesia (GA). METHODS: A systematic search was performed to identify relevant studies. Adult patients were included who had undergone craniotomy for high-grade glioma (WHO grade III or IV) using ISM (among which AC) or GA. Primary outcomes were rate of postoperative complications, overall postoperative survival, and percentage of gross total resections (GTR). Secondary outcomes were extent of resection and percentage of eloquent areas. RESULTS: Review of 2049 articles led to the inclusion of 53 studies in the analysis, including 9102 patients. The overall postoperative median survival in the AC group was significantly longer (16.87 versus 12.04 months; p < 0.001) and the postoperative complication rate was significantly lower (0.13 versus 0.21; p < 0.001). Mean percentage of GTR was significantly higher in the ISM group (79.1% versus 47.7%, p < 0.0001). Extent of resection and preoperative patient KPS were indicated as prognostic factors, whereas patient KPS and involvement of eloquent areas were identified as predictive factors. CONCLUSIONS: These findings suggest that surgeons using ISM and AC during their resections of high-grade glioma in eloquent areas experienced better surgical outcomes: a significantly longer overall postoperative survival, a lower rate of postoperative complications, and a higher percentage of GTR.


Assuntos
Mapeamento Encefálico/métodos , Neoplasias Encefálicas/cirurgia , Craniotomia/métodos , Glioma/cirurgia , Monitorização Neurofisiológica Intraoperatória/métodos , Complicações Pós-Operatórias/epidemiologia , Mapeamento Encefálico/efeitos adversos , Craniotomia/efeitos adversos , Estimulação Encefálica Profunda/efeitos adversos , Humanos , Monitorização Neurofisiológica Intraoperatória/efeitos adversos , Complicações Pós-Operatórias/etiologia , Vigília
11.
Pan Afr Med J ; 30: 201, 2018.
Artigo em Francês | MEDLINE | ID: mdl-30574220

RESUMO

INTRODUCTION: Halitosis is a morbid condition characterized by bad breath. Sometimes it has pathological and social implications. In the context of daily clinical practice, halitosis poses many diagnostic and therapeutic problems. This study aims to investigate the clinical and therapeutic features of this disorder. METHODS: We conducted a cross-sectional study over a one year period. Patients over the age of 15 years presenting with halitosis at the University Hospital Yalgado Ouedraogo were enrolled in the study. Patients with bad breath but presenting with some other problema were excluded. Patient's breath was assessed by a practitioner on the basis of Rosenberg organoleptic test. RESULTS: A total of 35 patients were included, with a sex ratio of 1.2. The average age of patients was 31.9 years. In 57.1% of cases, complaints were made by patients themselves. The mean duration of halitosis was 4.3 years. Nineteen patients had Mel Rosenberg score ≥ 2. Dental caries (07 cases), sinusitis (07 cases), Helicobacter pylori infection (09 cases) and gastrointestinal ulcer (10 cases) were associated with halitosis. Treatment was based on etiology in 82.9% of cases with satisfactory improvement after two weeks in 71.8% of cases. CONCLUSION: Halitosis is a little studied disorder which poses problem in positive diagnosis as well as etiologic problems in our context. The dentist plays a crucial role in identifying the possible cause of halitosis. However, multidisciplinary approach would enable a more effective response.


Assuntos
Cárie Dentária/complicações , Halitose/diagnóstico , Infecções por Helicobacter/complicações , Úlcera Péptica/complicações , Sinusite/complicações , Adolescente , Adulto , Burkina Faso , Estudos Transversais , Cárie Dentária/epidemiologia , Odontólogos/organização & administração , Feminino , Halitose/etiologia , Halitose/terapia , Infecções por Helicobacter/epidemiologia , Humanos , Comunicação Interdisciplinar , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/epidemiologia , Papel Profissional , Sinusite/epidemiologia , Adulto Jovem
12.
Artigo em Inglês | MEDLINE | ID: mdl-30309013

RESUMO

The cholera epidemic that occurred in Haiti post-earthquake in 2010 has resulted in over 9000 deaths during the past eight years. Currently, morbidity and mortality rates for cholera have declined, but cholera cases still occur on a daily basis. One continuing issue is an inability to accurately predict and identify when cholera outbreaks might occur. To explore this surveillance gap, a metagenomic approach employing environmental samples was taken. In this study, surface water samples were collected at two time points from several sites near the original epicenter of the cholera outbreak in the Central Plateau of Haiti. These samples underwent whole genome sequencing and subsequent metagenomic analysis to characterize the microbial community of bacteria, fungi, protists, and viruses, and to identify antibiotic resistance and virulence associated genes. Replicates from sites were analyzed by principle components analysis, and distinct genomic profiles were obtained for each site. Cholera toxin converting phage was detected at one site, and Shiga toxin converting phages at several sites. Members of the Acinetobacter family were frequently detected in samples, including members implicated in waterborne diseases. These results indicate a metagenomic approach to evaluating water samples can be useful for source tracking and the surveillance of pathogens such as Vibrio cholerae over time, as well as for monitoring virulence factors such as cholera toxin.


Assuntos
Cólera/epidemiologia , Água Doce/microbiologia , Qualidade da Água , Bactérias/genética , Bactérias/isolamento & purificação , DNA Bacteriano/análise , Surtos de Doenças , Farmacorresistência Bacteriana/genética , Haiti/epidemiologia , Humanos , Metagenômica , Fatores de Virulência/genética , Microbiologia da Água , Poluentes da Água/isolamento & purificação
13.
Clin Hemorheol Microcirc ; 69(3): 417-424, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29660907

RESUMO

BACKGROUND: Sickle cell trait (SCT) is a benign condition of sickle cell disease. Nevertheless, previous reports showed that SCT carriers have increased blood viscosity and decreased vascular reactivity compared to non-SCT carrier. The benefit of regular exercise on vascular function has been well documented in the general population but no study focused on the SCT population. PURPOSE: The aim of our study was to compare arterial stiffness and blood viscosity between trained and untrained SCT carriers, as well as a group of untrained non-SCT. METHODS: Arterial stiffness (finger-toe pulse wave velocity) and blood viscosity were evaluated in untrained non-SCT carriers (n = 10), untrained SCT carriers (n = 23) and trained SCT carriers (n = 17) who reported at least 10 hours of physical exercise per week. RESULTS: Untrained SCT carriers had higher pulse wave velocity (p = 0.032) and blood viscosity (p < 0.001) than their trained counterparts. In addition, untrained SCT carriers had higher blood viscosity (p < 0.001) than the untrained non-SCT group. A positive association was noted between blood viscosity and pulse wave velocity in the whole study population. CONCLUSION: Our study suggests that regular exercise may be beneficial for the vascular function of SCT carriers.


Assuntos
Viscosidade Sanguínea/fisiologia , Análise de Onda de Pulso/métodos , Traço Falciforme/sangue , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
14.
Mol Biol Rep ; 45(3): 203-209, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29404829

RESUMO

Identifying spatial patterns of genetic differentiation across a species range is critical to set up conservation and restoration decision-making. This is especially timely, since global change triggers shifts in species' geographic distribution and in the geographical variation of mating system and patterns of genetic differentiation, with varying consequences at the trailing and leading edges of a species' distribution. Using 454 pyrosequencing, we developed nuclear microsatellite loci for two plant species showing a strictly coastal geographical distribution and contrasting range dynamics: the expanding rock samphire (Crithmum maritimum, 21 loci) and the highly endangered and receding dune pansy (Viola tricolor subsp. curtisii, 12 loci). Population genetic structure was then assessed by genotyping more than 100 individuals from four populations of each of the two target species. Rock samphire displayed high levels of genetic differentiation (FST = 0.38), and a genetic structure typical of a mostly selfing species (FIS ranging from 0.16 to 0.58). Populations of dune pansy showed a less pronounced level of population structuring (FST = 0.25) and a genotypic structure more suggestive of a mixed-mating system when excluding two loci with heterozygote excess. These results demonstrate that the genetic markers developed here are useful to assess the mating system of populations of these two species. They will be tools of choice to investigate phylogeographical patterns and variation in mating system over the geographical distribution ranges for two coastal plant species that are subject to dynamic evolution due to rapid contemporary global change.


Assuntos
Apiaceae/genética , Viola/genética , Fluxo Gênico/genética , Marcadores Genéticos/genética , Variação Genética , Genética Populacional/métodos , Genótipo , Geografia/métodos , Heterozigoto , Repetições de Microssatélites , Polimorfismo Genético
15.
Mol Ecol ; 26(17): 4434-4451, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28667796

RESUMO

Human activities affect microevolutionary dynamics by inducing environmental changes. In particular, land cover conversion and loss of native habitats decrease genetic diversity and jeopardize the adaptive ability of populations. Nonetheless, new anthropogenic habitats can also promote the successful establishment of emblematic pioneer species. We investigated this issue by examining the population genetic features and evolutionary history of the natterjack toad (Bufo [Epidalea] calamita) in northern France, where populations can be found in native coastal habitats and coalfield habitats shaped by European industrial history, along with an additional set of European populations located outside this focal area. We predicted contrasting patterns of genetic structure, with newly settled coalfield populations departing from migration-drift equilibrium. As expected, coalfield populations showed a mosaic of genetically divergent populations with short-range patterns of gene flow, and native coastal populations indicated an equilibrium state with an isolation-by-distance pattern suggestive of postglacial range expansion. However, coalfield populations exhibited (i) high levels of genetic diversity, (ii) no evidence of local inbreeding or reduced effective population size and (iii) multiple maternal mitochondrial lineages, a genetic footprint depicting independent colonization events. Furthermore, approximate Bayesian computations suggested several evolutionary trajectories from ancient isolation in glacial refugia during the Pleistocene, with biogeographical signatures of recent expansion probably confounded by human-mediated mixing of different lineages. From an evolutionary and conservation perspective, this study highlights the ecological value of industrial areas, provided that ongoing regional gene flow is ensured within the existing lineage boundaries.


Assuntos
Bufonidae/classificação , Ecossistema , Fluxo Gênico , Genética Populacional , Animais , Teorema de Bayes , Carvão Mineral , DNA Mitocondrial/genética , França , Variação Genética , Mineração , Filogenia
16.
J Hered ; 107(7): 660-665, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27634537

RESUMO

Amphibians are undergoing a major decline worldwide and the steady increase in the number of threatened species in this particular taxa highlights the need for conservation genetics studies using high-quality molecular markers. The natterjack toad, Bufo (Epidalea) calamita, is a vulnerable pioneering species confined to specialized habitats in Western Europe. To provide efficient and cost-effective genetic resources for conservation biologists, we developed and characterized 22 new nuclear microsatellite markers using next-generation sequencing. We also used sequence data acquired from Sanger sequencing to develop the first mitochondrial markers for KASPar assay genotyping. Genetic polymorphism was then analyzed for 95 toads sampled from 5 populations in France. For polymorphic microsatellite loci, number of alleles and expected heterozygosity ranged from 2 to 14 and from 0.035 to 0.720, respectively. No significant departures from panmixia were observed (mean multilocus F IS = -0.015) and population differentiation was substantial (mean multilocus F ST = 0.222, P < 0.001). From a set of 18 mitochondrial SNPs located in the 16S and D-loop region, we further developed a fast and cost-effective SNP genotyping method based on competitive allele-specific PCR amplification (KASPar). The combination of allelic states for these mitochondrial DNA SNP markers yielded 10 different haplotypes, ranging from 2 to 5 within populations. Populations were highly differentiated (G ST = 0.407, P < 0.001). These new genetic resources will facilitate future parentage, population genetics and phylogeographical studies and will be useful for both evolutionary and conservation concerns, especially for the set-up of management strategies and the definition of distinct evolutionary significant units.


Assuntos
Bufonidae/classificação , Bufonidae/genética , DNA Mitocondrial , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Alelos , Animais , Variação Genética , Genética Populacional , Genótipo , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Reação em Cadeia da Polimerase
17.
Evol Appl ; 9(8): 1005-16, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27606008

RESUMO

Studying wild pathogen populations in natural ecosystems offers the opportunity to better understand the evolutionary dynamics of biotic diseases in crops and to enhance pest control strategies. We used simulations and genetic markers to investigate the spatial and temporal population genetic structure of wild populations of the beet cyst nematode Heterodera schachtii on a wild host plant species, the sea beet (Beta vulgaris spp. maritima), the wild ancestor of cultivated beets. Our analysis of the variation of eight microsatellite loci across four study sites showed that (i) wild H. schachtii populations displayed fine-scaled genetic structure with no evidence of substantial levels of gene flow beyond the scale of the host plant, and comparisons with simulations indicated that (ii) genetic drift substantially affected the residual signals of isolation-by-distance processes, leading to departures from migration-drift equilibrium. In contrast to what can be suspected for (crop) field populations, this showed that wild cyst nematodes have very low dispersal capabilities and are strongly disconnected from each other. Our results provide some key elements for designing pest control strategies, such as decreasing passive dispersal events to limit the spread of virulence among field nematode populations.

18.
Korean J Hepatobiliary Pancreat Surg ; 20(1): 23-31, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26925147

RESUMO

BACKGROUNDS/AIMS: The aim of this study was to describe clinical and biological changes in a group of patients who underwent pancreaticoduodenectomy (PD) without any complication during the postoperative period. These changes reflect the "natural history" of PD, and a deviation should be considered as a warning sign. METHODS: Between January 2000 and December 2009, 131 patients underwent PD. We prospectively collected and retrospectively analyzed demographic data, pathological variables, associated pathological conditions, and preoperative, intraoperative, and postoperative variables. Postoperative variables were validated using an external prospective database of 158 patients. RESULTS: The mean postoperative length of hospital stay was 20.3±4 days. The mean number of days until removal of nasogastric tube was 6.3±1.6 days. The maximal fall in hemoglobin level occurred on day 3 and began to increase after postoperative day (POD) 5, in patients with or without transfusions. The white blood cell count increased on POD 1 and persisted until POD 7. There was a marked rise in aminotransferase levels at POD 3. The peak was significantly higher in patients with hepatic pedicle occlusion (866±236 IU/L versus 146±48 IU/L; p<0.001). For both γ-glutamyl transpeptidase and alkaline phosphatase, there was a fall on POD1, which persisted until POD 5, followed with a stabilization. Bilirubin decreased progressively from POD 1 onwards. CONCLUSIONS: This study facilitates a standardized biological and clinical pathway of follow-up. Patients who do not follow this recovery indicator could be at risk of complications and additional exams should be made to prevent consequences of such complications.

19.
Evol Appl ; 9(3): 489-501, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26989440

RESUMO

The sustainability of modern agriculture relies on strategies that can control the ability of pathogens to overcome chemicals or genetic resistances through natural selection. This evolutionary potential, which depends partly on effective population size (N e ), is greatly influenced by human activities. In this context, wild pathogen populations can provide valuable information for assessing the long-term risk associated with crop pests. In this study, we estimated the effective population size of the beet cyst nematode, Heterodera schachtii, by sampling 34 populations infecting the sea beet Beta vulgaris spp. maritima twice within a one-year period. Only 20 populations produced enough generations to analyze the variation in allele frequencies, with the remaining populations showing a high mortality rate of the host plant after only 1 year. The 20 analyzed populations showed surprisingly low effective population sizes, with most having N e close to 85 individuals. We attribute these low values to the variation in population size through time, systematic inbreeding, and unbalanced sex-ratios. Our results suggest that H. schachtii has low evolutionary potential in natural environments. Pest control strategies in which populations on crops mimic wild populations may help prevent parasite adaptation to host resistance.

20.
Rev. etol. (Online) ; 13(2): iii-iii, dez. 2014.
Artigo em Português | Index Psicologia - Periódicos | ID: psi-67664
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