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1.
Ann Chir Plast Esthet ; 66(5): 364-370, 2021 Oct.
Artigo em Francês | MEDLINE | ID: mdl-33036789

RESUMO

OBJECTIVES: Facial palsy can be assessed using objective and subjective tools. The main purpose of this work was to use these tools to determine at 12 months the percentage of patients with sequelae and to specify the type of sequelae. MATERIAL AND METHODS: Twenty-three patients with facial palsy were followed in this prospective and longitudinal study. They have been evaluated every 3 months during a year with the House and Brackmann grading scale and the Sunnybrook Facial Grading System. At 12 months, group A was composed of patients with complete recovery and group B, patients with sequelae. RESULTS: At 3 months, in patients of group B, the House-Brackmann grading scale (P=0.0134), the Sunnybrook Facial Grading System global score (P=0.0283) and dynamic score (P=0.0148) were lower than group A. Moreover, the movement "brow lift" (P=0.0181) seems to be relevant to predict follow-up. Synkinesis on "brow lift" (P=0.0270) and the treatment delay (P=0.0384) increased for group B. Sex, age, paralyzed side and recurrence of facial palsy had no influence. CONCLUSION: Objective and subjective tools determine thresholds and predictive scores of recovery with sequelae at 1 year. Nevertheless, it is relevant to assess clinically specific facial movements, such as "brow lift", to specify a recovery potential and to predict sequelae a year after the onset of facial palsy. As the treatment delay influences recovery, drug treatment should be recommended as early as possible.


Assuntos
Paralisia de Bell , Paralisia Facial , Paralisia de Bell/complicações , Paralisia Facial/etiologia , Humanos , Estudos Longitudinais , Prognóstico , Estudos Prospectivos
2.
Genetica ; 147(1): 69-78, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30671744

RESUMO

The Montagu's harrier (Circus pygargus) is a semi-colonial raptor species widely but patchily distributed across the Palearctic region with recorded cases of philopatry and presence of extra-pair copulation. In order to assess Montagu's harrier spatial genetic structure and contemporary gene flow, we developed 16 new microsatellite markers using 454 pyrosequencing. Genotypes of 117 chicks sampled in a 200 × 300 km farmland area in Central Western France were analyzed to characterize genetic polymorphism at each locus and regional and fine-scale genetic structure. Fourteen markers were found polymorphic, with a number of alleles ranging from 3 to 11. The expected and observed heterozygosities ranged from 0.36 to 0.856 and from 0.35 to 0.868, respectively. A single genetic unit was found at the regional scale with higher genetic similarity observed at a small spatial scale (up to 10 km). Our results are consistent with overall large-scale juvenile and adult dispersal together with small-scale male philopatry. Cross-species amplification of this set of microsatellites makers has been successful in two closely related harrier species: the marsh harrier (Circus aeruginosus) and the Hen harrier (Circus cyaneus) for which 14 and 12 markers were polymorphic, respectively. These new microsatellite markers could be used to study the population genetic structure, contemporary gene flow and parentage analyses in these three species and to conduct microsatellite-based demographic inferences on the Montagu's harrier.


Assuntos
Aves/genética , Repetições de Microssatélites , Polimorfismo Genético , Animais , Aves/classificação , Feminino , Fluxo Gênico , Especiação Genética , Masculino
3.
Br J Cancer ; 117(1): 102-112, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28571041

RESUMO

BACKGROUND: Glioblastoma is the most common and most lethal primary brain cancer. CBF1 (also known as Recombination signal Binding Protein for immunoglobulin kappa J, RBPJ) is the cardinal transcriptional regulator of the Notch signalling network and has been shown to promote cancer stem-like cells (CSCs) in glioblastoma. Recent studies suggest that some of the malignant properties of CSCs are mediated through the activation of pro-invasive programme of epithelial-to-mesenchymal transition (EMT). Little is known whether CBF1 is involved in the EMT-like phenotype of glioma cells. METHODS: In a collection of GBM neurosphere lines, we genetically inhibited CBF1 and investigated the consequences on EMT-related properties, including in vitro invasiveness by Boyden chambers assay, chemoresistance using a clinical drug library screen and glycolytic metabolism assessing live-cell extracellular acidification rate. We also compared CBF1 expression in cells exposed to low and high oxygen tension. In silico analysis in large-scale Western and Eastern patient cohorts investigated the clinical prognostic value of CBF1 expression in low- and high-grade glioma as well as medulloblastoma. RESULTS: Mean CBF1 expression is significantly increased in isocitrate dehydrogenase 1 (IDH1) R132H mutant glioblastoma and serves as prognostic marker for prolonged overall survival in brain tumours, particularly after therapy with temozolomide. Hypoxic regions of glioblastoma have higher CBF1 activation and exposure to low oxygen can induce its expression in glioma cells in vitro. CBF1 inhibition blocks EMT activators such as zinc finger E-box-binding homeobox 1 (ZEB1) and significantly reduces cellular invasion and resistance to clinically approved anticancer drugs. Moreover, we indicate that CBF1 inhibition can impede cellular glycolysis. CONCLUSIONS: Mean CBF1 activation in bulk tumour samples serves as a clinical predictive biomarker in brain cancers but its intratumoral and intertumoral expression is highly heterogeneous. Microenvironmental changes such as hypoxia can stimulate the activation of CBF1 in glioblastoma. CBF1 blockade can suppress glioblastoma invasion in vitro in particular in cells undergone EMT such as those found in the hypoxic niche. Targeting CBF1 can be an effective anti-EMT therapy to impede invasive properties and chemosensitivity in those cells.


Assuntos
Neoplasias Encefálicas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/genética , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/genética , Hipóxia Tumoral/genética , Antineoplásicos Alquilantes/uso terapêutico , Western Blotting , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Linhagem Celular Tumoral , Sobrevivência Celular , Simulação por Computador , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Bases de Dados Factuais , Transição Epitelial-Mesenquimal/genética , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Glicólise/genética , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Isocitrato Desidrogenase/genética , Mutação , Invasividade Neoplásica/genética , Células-Tronco Neoplásicas/metabolismo , Prognóstico , RNA Mensageiro/metabolismo , Temozolomida , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
4.
Ecol Appl ; 27(5): 1594-1604, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28374916

RESUMO

Many species are migratory, resulting in a life cycle divided into periodic stages occurring in different habitats occupied for a limited amount of time. Estimating the time spent in each habitat is crucial to understanding how individuals modulate their activities and thus to evolutionary ecology and conservation biology. Several methods, including some recent promising advances, can be used to estimate stopover duration as well as arrival and departure probabilities at sites where individuals are monitored using capture-recapture sampling. Our objectives in this study were to (1) describe the available models to estimate stopover duration, (2) illustrate with an original data set what kinds of questions can be addressed using the most recent methods, and (3) to provide in a detailed appendix a practical guide for implementing these methods in E-SURGE software. To illustrate the potential of these models for testing biological hypotheses, we used a capture-recapture data set on marbled newts (Triturus marmoratus). We used time-dependent and time-elapsed-since-arrival effects (using both Markovian and semi-Markov processes for the latter) to model stopover duration and the probability of arriving in and departing from a breeding pond for this species and compared the relative performance of the resulting models. Our findings showed a strong sex effect on stopover duration: females stayed on average 5.63 weeks in a breeding pond whereas males stayed only 3.03 weeks. In both sexes, the retention probability was mainly influenced by the time already spent there. Consequently, individuals of the same sex stayed a similar amount of time in a pond, although they did not arrive simultaneously but successively. The selected data set demonstrated the flexibility of these methods and their potential relevance for applications in evolutionary ecology and conservation.


Assuntos
Migração Animal , Ecologia/métodos , Etologia/métodos , Triturus/fisiologia , Animais , Feminino , França , Masculino , Cadeias de Markov , Modelos Biológicos , Fatores Sexuais , Fatores de Tempo
5.
J Eur Acad Dermatol Venereol ; 29(4): 801-4, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24628777

RESUMO

BACKGROUND: Drug reaction with eosinophilia and systemic symptoms (DRESS) may relapse following introduction of drugs structurally unrelated to the initial culprit drug. OBJECTIVE: To assess the frequency and characteristics of recurrent drug eruptions in patients with history of DRESS. METHODS: Patients who had developed adverse cutaneous reaction after DRESS occurrence were recruited from the regional database of Upper Normandy in France. Rate of recurrences were compared with patients with Toxic Epidermal Necrolysis (TEN) and Stevens-Johnson syndrome (SJS) patients during the same time frame. RESULTS: Of the 60 cases of DRESS collected, 15 (25%) with recurrences were retained for analysis. Seven patients had a single recurrence, whereas eight patients had several relapses. In the patients with pre-existing DRESS, recurrences were incomplete, corresponding to cutaneous rash in 13 cases and associated with eosinophilia in seven cases. Internal organ involvement was observed in two cases. In contrast, a single recurrence was found out of 61 patients with TEN/SJS. CONCLUSION: Incomplete recurrences with structurally unrelated culprit drugs are a frequent phenomenon in DRESS patients.


Assuntos
Síndrome de Hipersensibilidade a Medicamentos/epidemiologia , Síndrome de Hipersensibilidade a Medicamentos/etiologia , França/epidemiologia , Humanos , Recidiva , Estudos Retrospectivos , Síndrome de Stevens-Johnson/epidemiologia
6.
Br J Dermatol ; 171(3): 580-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24904002

RESUMO

BACKGROUND: The incidence of myocardial events has been reported to be increased in patients with psoriasis. OBJECTIVES: To investigate whether psoriasis is an independent risk factor for coronary artery disease (CAD). METHODS: We compared the prevalence of psoriasis between case patients with a diagnosis of CAD based on coronary angiography findings and control patients with no CAD referred to the emergency surgery department for an acute noncardiovascular condition. Case and control patients were examined for the presence of psoriasis by two dermatologists. The prevalence of psoriasis was compared among patients with CAD according to CAD severity. Five-hundred cases and 500 age- and sex-matched controls were included. RESULTS: Using matched univariate analysis, the prevalence of psoriasis was about twofold higher in CAD case patients than in control patients [8·0% vs. 3·4%, odds ratio (OR) 2·64; 95% confidence interval (CI) 1·42-4·88]. Using unconditional multivariate analysis, the association of psoriasis with CAD appeared to be borderline significant (OR 1·84; 95% CI 0·99-3·40). Psoriasis in patients with CAD was significantly associated with three-vessel involvement relative to one-or two-vessel involvement (13·1% vs. 6·1%; OR 3·07; 95% CI 1·50-6·25). CONCLUSIONS: The prevalence of psoriasis is twofold higher in patients with CAD than in control patients without CAD. It is associated with a more severe coronary artery involvement.


Assuntos
Doença da Artéria Coronariana/etiologia , Psoríase/complicações , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco
7.
Artigo em Inglês | MEDLINE | ID: mdl-38811321

RESUMO

OBJECTIVE: The esthetic problems inherent to peripheral (PFP) are frequent causes of complaint. Make-up is advocated as a form of therapy and can alleviate symptoms of depression. The aim of the present study was to collect data on make-up habits in female PFP patients and assess links with esthetic and/or functional complaints. MATERIAL AND METHODS: Two questionnaires were drawn up to compare make-up habits in female PFP patients and women in the general population. The first was sent out between September and December 2019, to 39 House-Brackmann grade III PFP patients (group A), and the second on-line questionnaire was sent to a control population of 1385 women (group B). RESULTS: PFP patients used make-up more often than controls at weekends (χ2=16.38; P=0.0009) and while at home (χ2=8.21; P=0.042), and more often with foundation (χ2=17.21; P=0.0006) and lip make-up (χ2=59.31; P<0.0001). The greater their functional complaint, the less they made up their eyes. The greater their self-confidence and the more they felt attractive, the less they made up their lips. CONCLUSION: The differences in make-up use found in the present study aimed to mask facial palsy and were related to the esthetic complaint, impacting social life.

8.
Mol Ecol ; 22(22): 5516-30, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24118539

RESUMO

Genetic data are increasingly used in landscape ecology for the indirect assessment of functional connectivity, that is, the permeability of landscape to movements of organisms. Among available tools, matrix correlation analyses (e.g. Mantel tests or mixed models) are commonly used to test for the relationship between pairwise genetic distances and movement costs incurred by dispersing individuals. When organisms are spatially clustered, a population-based sampling scheme (PSS) is usually performed, so that a large number of genotypes can be used to compute pairwise genetic distances on the basis of allelic frequencies. Because of financial constraints, this kind of sampling scheme implies a drastic reduction in the number of sampled aggregates, thereby reducing sampling coverage at the landscape level. We used matrix correlation analyses on simulated and empirical genetic data sets to investigate the efficiency of an individual-based sampling scheme (ISS) in detecting isolation-by-distance and isolation-by-barrier patterns. Provided that pseudo-replication issues are taken into account (e.g. through restricted permutations in Mantel tests), we showed that the use of interindividual measures of genotypic dissimilarity may efficiently replace interpopulation measures of genetic differentiation: the sampling of only three or four individuals per aggregate may be sufficient to efficiently detect specific genetic patterns in most situations. The ISS proved to be a promising methodological alternative to the more conventional PSS, offering much flexibility in the spatial design of sampling schemes and ensuring an optimal representativeness of landscape heterogeneity in data, with few aggregates left unsampled. Each strategy offering specific advantages, a combined use of both sampling schemes is discussed.


Assuntos
Genética Populacional , Modelos Genéticos , Animais , Simulação por Computador , Meio Ambiente , Genótipo , Repetições de Microssatélites , Salamandridae/genética
9.
Br J Dermatol ; 168(4): 859-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23210619

RESUMO

BACKGROUND: Superficial cellulitis of the leg (erysipelas) is a frequent skin infection. Abscess formation is the most frequent local complication. Determinants of abscess formation in patients with leg cellulitis have not yet been clearly established. OBJECTIVE: To assess the risk factors for abscess formation in patients with leg cellulitis. METHODS: The clinical, biological and bacteriological records of all patients referred to the dermatology department of a university hospital for superficial cellulitis of the leg during a 3-year period were retrospectively reviewed. Using univariate and multivariate analysis, patients' main characteristics at baseline were compared between the group of patients who developed abscess and the group who did not. RESULTS: A total of 164 patients (93 female, 71 male), mean age 65±18 years, were included. Abscess occurred in 13 cases (8%). The following general factors were positively associated with abscess formation: male sex, smoking, alcohol abuse and delayed introduction of antibiotic treatment. Based on multivariate analysis, only chronic alcohol abuse [odds ratio (OR) 4·3, 95% confidence interval (CI)1·08-20·57] and delayed antibiotic treatment initiation (OR 1·4, 95% CI 1·02-2·04) remained independently associated with abscess formation. CONCLUSIONS: Alcohol abuse and delayed initiation of antibiotic treatment are risk factors for abscess formation in patients with cellulitis of the leg. Patients with these predictors must be monitored carefully for abscess formation.


Assuntos
Abscesso/complicações , Celulite (Flegmão)/complicações , Erisipela/complicações , Abscesso/tratamento farmacológico , Idoso , Antibacterianos/uso terapêutico , Celulite (Flegmão)/tratamento farmacológico , Erisipela/tratamento farmacológico , Feminino , Humanos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Fatores de Risco
11.
Artigo em Inglês | MEDLINE | ID: mdl-35842351

RESUMO

OBJECTIVES: The main aim of the study was to determine whether the perception of synkinesis by patients with peripheral facial palsy (PFP) matched their clinician's severity assessment. Secondary objectives comprised: (1) to determine whether objective measurement of synkinesis matched the patient's perception; and (2) is to identify factors influencing patients' perceptions. METHODS: This retrospective study took place from January to May 2020. Forty patients (8 per PFP grade, I-V/VI; 20 women, 20 men) filled out the Synkinesis Assessment Questionnaire (SAQ) and were assessed on the Sunnybrook Facial Grading System (SFGS). Photographs were analyzed on MEEI-Facegram software. RESULTS: Perceived synkinesis (total SAQ) matched objective grades (SFGS) (Z=2.89; P=0.004), especially for smiling (Z=3.84; P<0.001) and lip protrusion (Z=3.79; P<0.001). Synkinesis on lip protrusion was a more sensitive indicator of perceived synkinesis than synkinesis on smiling (Z=2.96; P=0.003). Duration (ρ=0.5137; P<0.001) and grade of PFP (Chi2=13.82; P=0.008) heightened the perception of synkinesis. CONCLUSION: Patient-reported outcome measures (PROMs) such as the SAQ are relevant for clinical evaluation.


Assuntos
Paralisia Facial , Sincinesia , Masculino , Humanos , Feminino , Estudos Retrospectivos , Sincinesia/etiologia , Sincinesia/complicações , Inquéritos e Questionários , Medidas de Resultados Relatados pelo Paciente
12.
Cell Death Discov ; 9(1): 452, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38086797

RESUMO

The application of patient-derived (PD) in vitro tumor models represents the classical strategy for clinical translational oncology research. Using these cellular heterogeneous cultures for the isolation of cancer stem cells (CSCs), suggested to be the main driver for disease malignancy, relies on the use of surrogate biomarkers or is based on CSC-enriching culture conditions. However, the ability of those strategies to exclusively and efficiently enrich for CSC pool has been questioned. Here we present an alternative in vitro CSC model based on the oncogenic transformation of single clone-derived human induced pluripotent stem cells (hiPSC). Hotspot mutations in the DNA encoding for the R132 codon of the enzyme isocitrate dehydrogenase 1 (IDH1) and codon R175 of p53 are commonly occurring molecular features of different tumors and were selected for our transformation strategy. By choosing p53 mutant glial tumors as our model disease, we show that in vitro therapy discovery tests on IDH1-engineered synthetic CSCs (sCSCs) can identify kinases-targeting chemotherapeutics that preferentially target tumor cells expressing corresponding genetic alteration. In contrast, neural stem cells (NSCs) derived from the IDH1R132H overexpressing hiPSCs increase their resistance to the tested interventions indicating glial-to-neural tissue-dependent differences of IDH1R132H. Taken together, we provide proof for the potential of our sCSC technology as a potent addition to biomarker-driven drug development projects or studies on tumor therapy resistance. Moreover, follow-up projects such as comparing in vitro drug sensitivity profiles of hiPSC-derived tissue progenitors of different lineages, might help to understand a variety of tissue-related functions of IDH1 mutations.

13.
Biomed Pharmacother ; 144: 112278, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34628166

RESUMO

The utility of patient-derived tumor cell lines as experimental models for glioblastoma has been challenged by limited representation of the in vivo tumor biology and low clinical translatability. Here, we report on longitudinal epigenetic and transcriptional profiling of seven glioblastoma spheroid cell line models cultured over an extended period. Molecular profiles were associated with drug response data obtained for 231 clinically used drugs. We show that the glioblastoma spheroid models remained molecularly stable and displayed reproducible drug responses over prolonged culture times of 30 in vitro passages. Integration of gene expression and drug response data identified predictive gene signatures linked to sensitivity to specific drugs, indicating the potential of gene expression-based prediction of glioblastoma therapy response. Our data thus empowers glioblastoma spheroid disease modeling as a useful preclinical assay that may uncover novel therapeutic vulnerabilities and associated molecular alterations.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Instabilidade Genômica , Glioma/tratamento farmacológico , Transcriptoma , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Análise Mutacional de DNA , Ensaios de Seleção de Medicamentos Antitumorais , Perfilação da Expressão Gênica , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Humanos , Mutação , Reprodutibilidade dos Testes , Esferoides Celulares , Fatores de Tempo
14.
Science ; 241(4867): 812-6, 1988 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-3043662

RESUMO

The glucocorticoid receptor regulates transcriptional initiation upon binding to its cognate hormone. A series of fusion genes was constructed to examine the mechanism of hormone-regulated transcriptional enhancement. The DNA binding domain of the bacterial LexA repressor was fused to receptor derivatives lacking the region that is necessary and sufficient for specific DNA binding and transcriptional enhancement at glucocorticoid response elements (GRE's). The resultant hybrid proteins activated transcription from promoters linked to the lex operator. Enhancement still required hormone binding by the hybrid receptor regardless of the exact positioning of the LexA binding domain within the protein. Thus, the unliganded hormone binding domain of the receptor acts as a strong but reversible inhibitor of receptor activity in a manner that is independent of the means by which the receptor recognizes DNA. The results also show directly that the receptor contains at least one "enhancement domain" other than that overlapping the GRE binding region; the second domain, enh2, occupies a region near the receptor amino terminus.


Assuntos
Proteínas de Bactérias/fisiologia , Regulação da Expressão Gênica , Receptores de Glucocorticoides/genética , Proteínas Recombinantes de Fusão/fisiologia , Proteínas Recombinantes/fisiologia , Proteínas Repressoras/fisiologia , Serina Endopeptidases , Fatores de Transcrição/fisiologia , Transcrição Gênica , Evolução Biológica , Escherichia coli/genética , Regiões Promotoras Genéticas , Transfecção
15.
Mol Ecol ; 17(15): 3496-505, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19160477

RESUMO

Gene flow in riverine species is constrained by the dendritic (branching) structure of the river network. Spatial genetic structure (SGS) of freshwater insects is particularly influenced by catchment characteristics and land use in the surroundings of the river. Gene flow also depends on the life cycle of organisms. Aquatic larvae mainly drift downstream whereas flying adults can disperse actively overland and along watercourses. In-stream movements can generate isolation by distance (IBD) at a local scale and differentiation between subcatchments. However, these patterns can be disrupted by overland dispersal. We studied SGS across the Loire River in the damselfly Calopteryx splendens which is able to disperse along and between watercourses. Our sampling design allowed us to test for overland dispersal effects on genetic differentiation between watercourses. Amplified fragment length polymorphism markers revealed high genetic differentiation at the catchment scale but the genetic structure did not reflect the geographical structure of sampling sites. We observed IBD patterns when considering the distance following the watercourse but also the Euclidean distance, i.e. the shortest distance, between pairs of sites. Altogether, our results support the hypothesis of overland dispersal between watercourses. From a conservation perspective, attention should be paid to the actual pathways of gene flow across complex landscapes such as river networks.


Assuntos
Água Doce/parasitologia , Fluxo Gênico , Insetos/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , França , Variação Genética , Genética Populacional , Geografia
16.
Mol Ecol ; 17(9): 2208-18, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18410291

RESUMO

Native to South America, the potato cyst nematode Globodera pallida is one of the principal pests of Andean potato crops and is also an important global pest following its introduction to Europe, Africa, North America, Asia and Oceania. Building on earlier work showing a clear south to north phylogeographic pattern in Peruvian populations, we have been able to identify the origin of Western European populations with high accuracy. They are all derived from a single restricted area in the extreme south of Peru, located between the north shore of the Lake Titicaca and Cusco. Only four cytochrome b haplotypes are found in Western Europe, one of them being also found in some populations of this area of southern Peru. The allelic richness at seven microsatellite loci observed in the Western European populations, although only one-third of that observed in this part of southern Peru, is comparable to the allelic richness observed in the northern region of Peru. This result could be explained by the fact that most of the genetic variability observed at the scale of a field or even of a region is already observed at the scale of a single plant within a field. Thus, even introduction via a single infected potato plant could result in the relatively high genetic variability observed in Western Europe. This finding has important consequences for the control of this pest and the development of quarantine measures.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Repetições de Microssatélites/genética , Nematoides/genética , Doenças das Plantas/parasitologia , Análise de Sequência de DNA , Solanum tuberosum/parasitologia , Alelos , Animais , Cruzamento , Citocromos b/genética , Europa (Continente) , Haplótipos , Peru , Filogenia
17.
Theriogenology ; 69(6): 737-45, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18255134

RESUMO

The aim of the present study was to assess the effects of exposing fertile chicken eggs to a cell phone repeatedly calling a ten-digit number at 3-min intervals over the entire period of incubation. A pre-experiment was performed first to adjust incubation conditions in an experimental chamber devoid of metallic content and without automatic turning until the overall performance of hatchability was reproducible in the absence of the cell phone. The experimental period consisted of a series of 4 incubations referred to as "replicates". For each replicate, one batch of 60 eggs was exposed to the immediate environment (

Assuntos
Telefone Celular , Embrião de Galinha , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental/efeitos adversos , Animais , Embrião de Galinha/fisiologia , Ondas de Rádio , Sobrevida , Fatores de Tempo
18.
Mol Cell Biol ; 19(12): 8422-32, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10567567

RESUMO

The protein kinase Gcn2 stimulates translation of the yeast transcription factor Gcn4 upon amino acid starvation. Using genetic and biochemical approaches, we show that Gcn2 is regulated by the molecular chaperone Hsp90 in budding yeast Saccharomyces cerevisiae. Specifically, we found that (i) several Hsp90 mutant strains exhibit constitutive expression of a GCN4-lacZ reporter plasmid; (ii) Gcn2 and Hsp90 form a complex in vitro as well as in vivo; (iii) the specific inhibitors of Hsp90, geldanamycin and macbecin I, enhance the association of Gcn2 with Hsp90 and inhibit its kinase activity in vitro; (iv) in vivo, macbecin I strongly reduces the levels of Gcn2; (v) in a strain expressing the temperature-sensitive Hsp90 mutant G170D, both the accumulation and activity of Gcn2 are abolished at the restrictive temperature; and (vi) the Hsp90 cochaperones Cdc37, Sti1, and Sba1 are required for the response to amino acid starvation. Taken together, these data identify Gcn2 as a novel target for Hsp90, which plays a crucial role for the maturation and regulation of Gcn2.


Assuntos
Proteínas de Ligação a DNA , Proteínas de Drosophila , Proteínas Fúngicas/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae , Regiões 5' não Traduzidas , Benzoquinonas , Proteínas de Ciclo Celular/metabolismo , Chaperoninas , Proteínas Fúngicas/genética , Expressão Gênica , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Óperon Lac , Lactamas Macrocíclicas , Ligantes , Chaperonas Moleculares/metabolismo , Mutagênese , Fatores de Iniciação de Peptídeos/genética , Biossíntese de Proteínas , Proteínas Quinases/genética , Quinonas , RNA Mensageiro , Saccharomyces cerevisiae
19.
Mol Cell Biol ; 21(22): 7569-75, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11604493

RESUMO

The highly abundant molecular chaperone Hsp90 functions with assistance from auxiliary factors, collectively referred to as Hsp90 cochaperones, and the Hsp70 system. Hsp104, a molecular chaperone required for stress tolerance and for maintenance of [psi(+)] prions in the budding yeast Saccharomyces cerevisiae, appears to collaborate only with the Hsp70 system. We now report that several cochaperones previously thought to be dedicated to Hsp90 are shared with Hsp104. We show that the Hsp90 cochaperones Sti1, Cpr7, and Cns1, which utilize tetratricopeptide repeat (TPR) domains to interact with a common surface on Hsp90, form complexes with Hsp104 in vivo and that Sti1 and Cpr7 interact with Hsp104 directly in vitro. The interaction is Hsp90 independent, as further emphasized by the fact that two distinct TPR domains of Sti1 are required for binding Hsp90 and Hsp104. In a striking parallel to the sequence requirements of Hsp90 for binding TPR proteins, binding of Sti1 to Hsp104 requires a related acidic sequence at the C-terminal tail of Hsp104. While Hsp90 efficiently sequesters the cochaperones during fermentative growth, respiratory conditions induce the interaction of a fraction of Hsp90 cochaperones with Hsp104. This suggests that cochaperone sharing may favor adaptation to altered metabolic conditions.


Assuntos
Proteínas de Transporte/metabolismo , Ciclofilinas , Proteínas Fúngicas/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico/metabolismo , Chaperonas Moleculares/metabolismo , Peptidilprolil Isomerase/metabolismo , Proteínas de Saccharomyces cerevisiae , Sequência de Aminoácidos , Sítios de Ligação , Proteínas de Transporte/genética , Peptidil-Prolil Isomerase F , Proteínas Fúngicas/genética , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico/genética , Chaperonas Moleculares/genética , Dados de Sequência Molecular , Peptidilprolil Isomerase/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
20.
Mol Biol Cell ; 9(11): 3071-83, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9802897

RESUMO

The heat-shock protein 90 (Hsp90) is a cytosolic molecular chaperone that is highly abundant even at normal temperature. Specific functions for Hsp90 have been proposed based on the characterization of its interactions with certain transcription factors and kinases including Raf in vertebrates and flies. We therefore decided to address the role of Hsp90 for MAP kinase pathways in the budding yeast, an organism amenable to both genetic and biochemical analyses. We found that both basal and induced activities of the pheromone-signaling pathway depend on Hsp90. Signaling is defective in strains expressing low levels or point mutants of yeast Hsp90 (Hsp82), or human Hsp90beta instead of the wild-type protein. Ste11, a yeast equivalent of Raf, forms complexes with wild-type Hsp90 and depends on Hsp90 function for accumulation. For budding yeast, Ste11 represents the first identified endogenous "substrate" of Hsp90. Moreover, Hsp90 functions in steroid receptor and pheromone signaling can be genetically separated as the Hsp82 point mutant T525I and the human Hsp90beta are specifically defective for the former and the latter, respectively. These findings further corroborate the view that molecular chaperones must also be considered as transient or stable components of signal transduction pathways.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte , Proteínas de Choque Térmico HSP90/metabolismo , Peptídeos/metabolismo , Feromônios/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Proteínas de Schizosaccharomyces pombe , Transdução de Sinais , Ciclo Celular , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Fator de Acasalamento , Quinases de Proteína Quinase Ativadas por Mitógeno , Mutagênese , Fosforilação , Proteínas Quinases/metabolismo , Saccharomyces cerevisiae/genética , Temperatura , Fatores de Transcrição/metabolismo
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