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RATIONALE AND OBJECTIVES: The dogma is that normal parathyroid glands (PTGs) are not visible on ultrasound (US). Recently, several studies have shown that PTGs present these US features: ovoid structure, homogeneous and hyperechoic. The primary objective was to assess the detection rate, standard size and locations of normal PTGs in a population of patients consulting for thyroid US exam. The secondary objective was to determine if the presence of a goiter or a thyroiditis could modify the visualization of normal PTGs. METHOD: Single-center prospective study on 192 patients based on the typical US appearance previously described to identify one or more PTGs. RESULTS: One or more PTGs were visualized in 75% of patients (144/192). They were visualized preferentially at the lower pole of the thyroid gland and in the infra-thyroid region (66%). The mean (± SD) size of normal PTGs was 5.68 mm (± 1,42 mm)×4.05 mm (± 1,03 mm)×2,68 mm (± 0,61 mm) and mean volume was 33.3 mm3 (± 17.75 mm3). The presence of a goiter made the search for PTGs more difficult whereas the presence of thyroiditis facilitated it. CONCLUSION: The US detection rate of PTGs is high (75%). The identification of PTGs could be particularly useful in the preoperative assessment before total thyroidectomy or parathyroid surgery. It could reduce the risk of postoperative hypoparathyroidism and improve the accuracy of postoperative US surveillance of thyroid cancer. Better knowledge of the usual anatomical location of normal PTGs could also enable better detection of abnormal glands.
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Information on the onset of leaf senescence in temperate deciduous trees and comparisons on its assessment methods are limited, hampering our understanding of autumn dynamics. We compare five field proxies, five remote sensing proxies and two data analysis approaches to assess leaf senescence onset at one main beech stand, two stands of oak and birch, and three ancillary stands of the same species in Belgium during 2017 and 2018. Across species and sites, onset of leaf senescence was not significantly different for the field proxies based on Chl leaf content and canopy coloration, except for an advanced canopy coloration during the extremely dry and warm 2018. Two remote sensing indices provided results fully consistent with the field data. A significant lag emerged between leaf senescence onset and leaf fall, and when a threshold of 50% change in the seasonal variable under study (e.g. Chl content) was used to derive the leaf senescence onset. Our results provide unprecedented information on the quality and applicability of different proxies to assess leaf senescence onset in temperate deciduous trees. In addition, a sound base is offered to select the most suited methods for the different disciplines that need this type of data.
Assuntos
Florestas , Folhas de Planta/crescimento & desenvolvimento , Estações do Ano , Árvores/crescimento & desenvolvimento , Especificidade da Espécie , Fatores de TempoRESUMO
Living systems can generate an enormous range of cellular functions, from mechanical infrastructure and signalling networks to enzymatic catalysis and information storage, using a notably limited set of chemical functional groups. This observation is especially notable when compared to the breadth of functional groups used as the basis for similar functions in synthetically derived small molecules and materials. The relatively small cross-section between biological and synthetic reactivity space forms the foundation for the development of bioorthogonal chemistry, in which the absence of a pair of reactive functional groups within the cell allows for a selective in situ reaction1-4. However, biologically 'rare' functional groups, such as the fluoro5, chloro6,7, bromo7,8, phosphonate9, enediyne10,11, cyano12, diazo13, alkene14 and alkyne15-17 groups, continue to be discovered in natural products made by plants, fungi and microorganisms, which offers a potential route to genetically encode the endogenous biosynthesis of bioorthogonal reagents within living organisms. In particular, the terminal alkyne has found broad utility via the Cu(I)-catalysed azide-alkyne cycloaddition 'click' reaction18. Here we report the discovery and characterization of a unique pathway to produce a terminal alkyne-containing amino acid in the bacterium Streptomyces cattleya. We found that L-lysine undergoes an unexpected reaction sequence that includes halogenation, oxidative C-C bond cleavage and triple bond formation through a putative allene intermediate. This pathway offers the potential for de novo cellular production of halo-, alkene- and alkyne-labelled proteins and natural products from glucose for a variety of downstream applications.
Assuntos
Alcinos/química , Alcinos/metabolismo , Aminoácidos/biossíntese , Aminoácidos/química , Vias Biossintéticas , Streptomyces/metabolismo , Alcadienos/química , Alcadienos/metabolismo , Alcenos/química , Alcenos/metabolismo , Proteínas de Bactérias/metabolismo , Vias Biossintéticas/genética , Carbono/química , Carbono/metabolismo , Glucose/química , Glucose/metabolismo , Halogenação , Lisina/química , Lisina/metabolismo , Família Multigênica/genética , Serina/análogos & derivados , Serina/biossíntese , Serina/química , Streptomyces/genéticaRESUMO
This article tries to reconsider the relationship to work that one can develop to the point when it impacts the intimate sphere. To do so, it shall question the role of the sexualisation of the suffering between subject and object of a work/job that has become the vector of an enjoyable torment. The study will focus on the clinical case of a patient who is being treated in psychoanalytical psychotherapy (she started the therapy 5 years ago). This patient maintains a relationship to her work that could be defined as "addictive." The approach will be to use the psychodynamics of work (Dejours, 1992. "Pathologie de la communication. Situation de travail et espace public: le cas du nucléaire." In Pouvoir et légitimité, Raison pratiques, edited by A. Cotterau and P. Ladrière, vol. 3, 177-201. Paris: Éditions de l'EHESS; 2003. L'évaluation du travail à l'épreuve du réel: Critiques des fondements de l'évaluation. Paris: INRAA Editions) in perspective of Paul Denis's work on satisfaction and influence. Therefore, it will clinically illustrate the process inherent in the subversive and intimate perversion of the relationship to work: between resistance and suffering serving a satisfaction for which the relations of impulsive subordination (between means and goal) have been inverted to the benefit of a repetitive compulsion.
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We report the use of an Ultrafast 2D NMR approach applied on a benchtop NMR system (43â¯MHz) for the authentication of edible oils. Our results demonstrate that a profiling strategy based on fast 2D NMR spectra recorded in 2.4â¯min is more efficient than the standard 1D experiments to classify oils from different botanical origins, since 1D spectra on the same samples suffer from strong peak overlaps. Six edible oils with different botanical origins (olive, hazelnut, sesame, rapeseed, corn and sunflower) have been clearly discriminated by PCA analysis. Furthermore, we show how this approach combined with a PLS model can detect adulteration processes such as the addition of hazelnut oil into olive oil, a common fraud in food industry.
Assuntos
Contaminação de Alimentos/análise , Espectroscopia de Ressonância Magnética/métodos , Óleos de Plantas/análise , Óleos de Plantas/classificação , Óleo de Milho/análise , Corylus/química , Azeite de Oliva/análise , Óleo de Brassica napus/análise , Óleo de Gergelim/análise , Óleo de Girassol/análiseRESUMO
This paper deals with the dynamic modeling and simulation of cell damage heterogeneity and associated mutant cell phenotypes in the therapeutic responses of cancer cell populations submitted to a radiotherapy session during in vitro assays. Each cell is described by a finite number of phenotypic states with possible transitions between them. The population dynamics is then given by an age-dependent multi-type branching process. From this representation, we obtain formulas for the average size of the global survival population as well as the one of subpopulations associated with 10 mutation phenotypes. The proposed model has been implemented into Matlab© and the numerical results corroborate the ability of the model to reproduce four major types of cell responses: delayed growth, anti-proliferative, cytostatic and cytotoxic.
Assuntos
Dano ao DNA/efeitos da radiação , Modelos Biológicos , Mutação/efeitos da radiação , Radioterapia/efeitos adversos , Células Tumorais Cultivadas/efeitos da radiação , HumanosRESUMO
In teleost fish, thyroid function is involved in various critical physiological processes. Given the complexity of the hypothalamo-pituitary-thyroid (HPT) axis, a large number of genes and proteins can be the potential target of endocrine-disrupting compounds (EDCs). The aim of this study was to evaluate, in yellow and silver European eels (Anguilla anguilla), potential effects of EDCs on thyroid status by analyzing the associations between EDC body burdens and thyroid hormones (THs). In yellow individuals, greater free T3/T4 ratios (FT3/FT4) and lower plasma FT4 levels were associated with greater concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), as highlighted by significant correlations with many congeners. Few positive relationships with alkylphenols were noticed. In contrast, silver eels usually exhibited less significant correlations between THs and contaminant loads. Expression of a series of genes involved in the HPT axis was also investigated in the silver individuals. Concerning mRNA expression in silver females, some main correlations were noticed: thyroid-stimulating hormone (TSHß) gene expression was significantly correlated to numerous PCBs, and hepatic mRNA levels of deiodinase 2 (Deio 2) were negatively correlated to 2-hydroxyfluorene (2-OHF) and 2-naphtol (2-OHNa). Thyroid receptor (TRα and TRß) mRNA levels exhibited weak negative correlations with some PBDEs in silver females and males. Hepatic vitellogenin (Vtg) mRNA levels were detected in all silver males but at lower levels than in silver females. In males, Vtg mRNA levels were positively associated to FT4/TT4. In silver females, strong positive correlations were found between congeners of PCBs, PBDEs and PFAS suggesting potential estrogenic effects. Overall, the observed results indicate that several organic contaminants, mainly dl-, ndl-PCBs and PBDEs, could be associated with changes in thyroid homeostasis in these fish, via direct or indirect interactions with peripheral deiodination, metabolism of T4 and mechanisms involved in TSHß, Deio 2 and Vtg gene transcription.
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Anguilla/fisiologia , Disruptores Endócrinos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Feminino , França , Éteres Difenil Halogenados/metabolismo , Bifenilos Policlorados/metabolismo , Glândula Tireoide/metabolismo , Hormônios Tireóideos/sangue , Tireotropina/metabolismo , Vitelogeninas/metabolismoRESUMO
BACKGROUND: Scapulo-humeral arthrodesis (SHA) is a proven reconstruction method in patients with proximal humerus malignancies requiring resection of the shoulder abduction apparatus (rotator cuff and deltoid muscles) or its nerve supply. Standard practice consists in using a pedicled fibular flap. We use instead a pedicled autologous bone graft harvested from the ipsilateral scapular pillar. HYPOTHESIS: The objective of this study was to assess functional outcomes and radiological healing after SHA using a pedicled scapular pillar graft. MATERIALS AND METHODS: We retrospectively reviewed the charts of the 12 patients managed at a single center by a single surgeon between 1994 and 2011. SHA was performed using a vascularised ipsilateral scapular pillar graft after proximal humerus resection to treat a bone malignancy. The graft was harvested from the ipsilateral scapular pillar, pedicled on the circumflex scapular artery, fitted into the remaining proximal humerus, and secured to the glenoid using screws. A humerus-scapular spine plate was added to stabilize the arthrodesis. Radiographic results were assessed on standard radiographs obtained at last follow-up. Functional outcomes were evaluated using the MusculoSkeletalTumour Society (MSTS) score and Toronto Extremity Salvage Score (TESS). RESULTS: After a mean follow-up of 4.9 years, 87.5% of SHA junctions were healed, mean MSTS score was 71%, and mean TESS score was 70%. DISCUSSION: The outcomes in our patients were similar to those reported after SHA using a pedicled fibular flap. However, our technique does not require microsurgery. It is simple, reproducible, and effective. Its indications of choice are intra- or extra-articular resection of the proximal humerus including the attachments of the rotator cuff and deltoid muscle tendons or the nerves supplying these muscles. LEVEL OF EVIDENCE: Level IV (retrospective study).
Assuntos
Artrodese , Úmero/cirurgia , Escápula/cirurgia , Escápula/transplante , Retalhos Cirúrgicos , Adolescente , Adulto , Idoso , Neoplasias Ósseas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sarcoma/cirurgia , Músculos Superficiais do Dorso/transplante , Adulto JovemRESUMO
BACKGROUND: Since 2002 the Belgian law requires an informed consent of the patient before each medical intervention. This provision applies also for adolescent patients on condition that the physician considers the young patient as competent to autonomously participate in the decision making process. AIM: The purpose of this study is to evaluate to what extent Belgian paediatricians from the Flemish part of the country have implemented the legal requirements for informed consent of adolescent patients, in particular when they consult alone. METHODS: In the frame of a larger study regarding the relation between paediatricians and their patients, a questionnaire was sent via regular mail to 570 Flemish paediatricians, evaluating how and how often they obtain an informed consent of the adolescent when consulting a physician unaccompanied. RESULTS: In only 1% of all consultations an adolescent consulted the physician alone and agreed to a medical intervention on his/her own. The information given by the paediatrician did not differ if the adolescent consulted alone or was accompanied by (one of) his/her parents for the following items: purpose and type of treatment (100% vs 100%), duration of treatment (92% vs 94%) and aftercare (89% vs 93%). However, the information differed with regard to alternatives to the treatment (65% vs 76%), degree of urgency (89% vs 95% ), treatment related risks (82% vs 90%) and cost (21% vs 45%). 18.6% of the paediatricians consider age as the single criterion to evaluate the competence of the adolescent to provide an informed consent; other criteria that are considered: experience (92%), insight into and factual understanding of the clinical picture (84%). To fulfil the tasks of providing information and asking for consent, paediatricians rarely had recourse to prior established protocols (14%), they preferred to rely on proper experience and expertise (81%). Fifty percent appealed to the opinion of other health care providers. CONCLUSIONS: Although the Belgian law stipulates regulations that should be complied with by the physician during the decision making process about any medical intervention on adolescents, this legislation has rarely been put into practice, as the adolescents used their right to autonomously consent in barely 1% of all paediatric consultations. For the majority of the respondents other criteria than age were taken into account to consider an adolescent as able to provide informed consent.
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Atitude do Pessoal de Saúde , Consentimento Informado por Menores/legislação & jurisprudência , Pediatria , Adolescente , Adulto , Bélgica , Criança , Feminino , Humanos , Consentimento Informado por Menores/psicologia , Consentimento Informado por Menores/estatística & dados numéricos , Masculino , Competência Mental/legislação & jurisprudência , Competência Mental/psicologia , Pessoa de Meia-Idade , Padrões de Prática Médica , Inquéritos e QuestionáriosAssuntos
Queimaduras por Corrente Elétrica/etiologia , Queimaduras por Inalação/etiologia , Eletrocirurgia/efeitos adversos , Incêndios , Complicações Intraoperatórias/etiologia , Traqueia/lesões , Traqueotomia , Aerossóis , Idoso , Eletrocirurgia/instrumentação , Segurança de Equipamentos , Feminino , Humanos , Intubação Intratraqueal , Maxila/cirurgia , Esvaziamento Cervical , Oxigênio , Silicones , VolatilizaçãoRESUMO
BACKGROUND: The law on patients' rights in Belgium was issued in 2002. The new legal framework recommends the establishment of a true dialogue between physician and patient, and it assigns decisive priority to the adolescent rather than to the physician or his parents. PURPOSE AND METHODS: The purpose of this study is to map the current interpretation of the paediatrician and the realisation of the law in practice. The answers of 117 Flemish paediatricians to an anonymous questionnaire were analyzed. RESULTS: Only 7.8% of the paediatricians state that they know the law well. 15.5% experience the law as a burden. 20.9% have adopted a different attitude when rendering care to adolescents under impulse of this law. 6.2% say they do not strictly follow the law. 27.8% think that the emancipating thought is too far-reaching. Most paediatricians apply protocols to interpret the traditional values that are stamped as being good medical practice: high quality care (81%), free patient's choice (70.7%), adequate pain control (77.4%). On the other hand paediatricans seldom dispose of procedures regarding the more emancipated amenities in the law such as obtaining informed consent (16.4%), access to the medical file (24.8%) and safe-guarding the privacy (13%). In practice most of the physicians offer the possibility of a free choice in 80% of the cases. All questioned physicians strive for a high quality care, for adequate pain control and for a careful maintained medical file. 79.1% of the physicians transfer to the parents all medical information regarding the adolescent. Proper experience and expertise (80.7%), case by case completed, are most often used as the basis for the judgment about the competence of the adolescent. From the patient's side, little advance is taken to exercise his own rights. Barely 1% of the adolescents consulting a paediatrician use their legal right to autonomously consent to a medical intervention. In barely 0.16% access is requested to the medical file. Practically no complaints are received regarding the law on patients' rights (0.1% in intramural setting, versus 0.001% extramural). CONCLUSION: The law on patients' rights is, after 8 years of issuance, badly penetrated in the paediatric practice. On the one hand this is due to a poor knowledge of the law as well from the side of the physician as from the side of the adolescent and/or his parents. On the other hand 42.2% of the paediatricians experience difficulties with the practical interpretation of the law because of the lack of applicable guidelines. An important obstacle is the fact that more than a quarter of the paediatricians do not agree with the in the law foreseen autonomy of the adolescents. For that reason, paediatricians urgently need to be instructed in these matters. It is the moral duty of the Society of Paediatrics to organize workshops on these matters and develop clear guidelines concerning this law. Proper application of the legal context, the handling of the watertight procedures and the necessary communication in this respect is indispensable for the confidence and will lower the barrier for adolescents to use the healthcare system.
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Direitos do Paciente/legislação & jurisprudência , Relações Médico-Paciente , Padrões de Prática Médica , Adolescente , Adulto , Bélgica , Confidencialidade/legislação & jurisprudência , Tomada de Decisões , Feminino , Humanos , Consentimento Informado por Menores/legislação & jurisprudência , Masculino , Pessoa de Meia-Idade , Pediatria/organização & administração , Autonomia PessoalRESUMO
OBJECTIVE: The Estimating Ambulation Capacity by History-Questionnaire (EACH-Q) and the Walking Impairment Questionnaire (WIQ) are used to estimate maximal walking distance (MWD). The EACH-Q and WIQ included 4 and 14 items respectively, among which one item dealing with running capacity. We hypothesised that this item was of little interest in patients with claudication. DESIGN: The WIQ and EACH-Q were self-completed and corrected before a constant load (3.2 km h(-1); 10% slope) treadmill tests, maximised to 15 min. PATIENTS: 371 patients (298 males/73 females, 62.9 ± 11.2 years). METHODS: The number of errors (duplicate, absent or paradoxical answers to one item) and correlation of questionnaire scores with MWD on treadmill were calculated, before and after skipping the answer to the running item. RESULTS: The proportion of questionnaires with errors was 27% with the EACH-Q and 48% with the WIQ. Two-hundred and twenty-one (59.6%) and 245 (66%) out of 371 patients reported to be unable to run, for the EACH-Q and WIQ, respectively. The rate of errors was reduced by 15% for the EACH-Q (p < 0.05) when skipping the running item for scoring. The correlation coefficients between the MWD and the questionnaire scores were 0.449 and 0.485 for the EACH-Q and were 0.571 and 0.572 for the WIQ, before and after skipping the running item, respectively. CONCLUSION: Most of our patients reported to be unable to run and skipping the running item reduce the rate of errors in self-completing the questionnaires without impairing the correlation of questionnaire scores with treadmill results. It is likely that the running item could be removed from the WIQ and EACH-Q questionnaires.
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Avaliação da Deficiência , Tolerância ao Exercício , Claudicação Intermitente/diagnóstico , Corrida , Inquéritos e Questionários , Caminhada , Idoso , Feminino , França , Humanos , Claudicação Intermitente/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Índice de Gravidade de DoençaRESUMO
We assessed the pools of non-structural nitrogen compounds (NSNC) through a year, thereby addressing the question of whether mature sessile oak [Quercus petraea (Matt.) Liebl.] and beech (Fagus sylvatica L.), which differ in wood anatomy and growth patterns, exhibit contrasting seasonal dynamics of NSNC pools as previously shown for non-structural carbohydrate (NSC) pools. Seasonal fluctuations of NSNC (amino acids and soluble proteins) and NSC (starch and soluble sugars) pools were analyzed in the inner and the outer stem sapwood. In oak, NSC showed marked seasonal variation within the stem sapwood (accumulation during winter and decrease during bud burst and early wood growth), whereas in beech seasonal fluctuations in NSC were of minor amplitude. Even if the distribution and intensity of the NSNC pools differed between the two species, NSNC of the stem sapwood did not show seasonal variation. The most significant change in NSNC pools was the seasonal fluctuation of protein composition. In both species, two polypeptides of 13 kDa (PP13) and 26 kDa (PP26) accumulated during the coldest period in parallel with starch to sugar conversion and disappeared with the onset of spring growth. The absence of seasonal changes in total soluble protein concentration suggests that the polypeptides are involved in the internal nitrogen (N) cycling of the stem rather than in N storage and remobilization to the other growing organs of the tree.
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Metabolismo dos Carboidratos , Fagus/metabolismo , Compostos de Nitrogênio/metabolismo , Quercus/metabolismo , Estações do Ano , Fagus/crescimento & desenvolvimento , Caules de Planta/crescimento & desenvolvimento , Quercus/crescimento & desenvolvimento , TemperaturaRESUMO
The computation of standardized incidence/mortality ratios or Poisson regression requires the calculation of person-years generated in a cohort. Softwares can do that, but SAS users still need to program this step themselves. Various algorithms were published previously, but they do not perform exact calculations: the present paper describes a simple program, which creates exact person-years, and computes SMRs. This program provides a referenced tool to perform this analysis in a cohort, with SAS or another language (the algorithm used can be easily adapted).
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Interpretação Estatística de Dados , Mortalidade , Software , Humanos , Fatores de TempoRESUMO
GOAL OF STUDY: Treatment of splenic injury is not standardized. We conducted an inventory of splenic injury treatment modalities of splenic injury in the Languedoc-Roussillon region of France. METHODS: A questionnaire was sent by e-mail to 33 surgeons practicing in 10 hospitals in that region. Surgeons were asked: how many cases were treated per year (PMSI databank for the last three years), local resources (resuscitation bay or intensive care unit, availability of CT and interventional radiology), indications (surgery, embolization, nonoperative management [NOM]), prognostic criteria, NOM modalities (duration of bed rest, hospital stay, restriction of physical activity, thromboembolic prophylaxis, and imaging schedule). RESULTS: Thirty-one surgeons replied. An average of 185 patients were treated per year. There was consensus concerning the indication for urgent splenectomy, NOM was practiced in the stable patient (even with diffuse hemoperitoneum) and splenic artery embolization was performed for active bleeding (blush on CT) (for the six centers who have interventional radiology at their disposal). Disparities existed between centers concerning the modalities of NOM excepting imaging monitoring, initial surveillance in resuscitation bay or intensive care and in the therapeutic indications when bleeding persisted. CONCLUSION: Based on the consensus observed in this study and an analysis of the literature, a uniform treatment policy can be proposed.
Assuntos
Contusões/terapia , Embolização Terapêutica/estatística & dados numéricos , Emergências , Baço/lesões , Esplenectomia/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Consenso , Contusões/diagnóstico por imagem , França , Hemoglobinometria , Hemoperitônio/diagnóstico por imagem , Hemoperitônio/terapia , Humanos , Radiologia Intervencionista , Fatores de Risco , Baço/irrigação sanguínea , Baço/diagnóstico por imagem , Artéria Esplênica/diagnóstico por imagem , Inquéritos e Questionários , Revisão da Utilização de Recursos de Saúde/estatística & dados numéricosRESUMO
In this study, new DNA markers were explored for the flounder Platichthys flesus. cDNA and genomic sequences of the genes encoding the glyceraldehyde-3-phosphate-deshydrogenase (GAPDH), the cytosolic creatine kinase (CK), the prostaglandin D synthase (PGDS) and the betaine homocysteine methyltransferase (BHMT) were characterized. The tumour suppressor p53 gene structure was already described. A PCR-SSCP (Single Strand Conformation Polymorphism) analysis was finally conducted to study the genetic polymorphism of different populations of flounders collected along the French Atlantic coast. Four highly contaminated French estuaries (Seine, Vilaine, Loire and Gironde) were sampled and compared to a reference estuary (Ster) to explore possible selective effect of the environment on specific allelic frequencies. Our results showed that two loci p53 and PGDS, could be potential markers of chemical stress: p53A allele frequency increased in contaminated systems compared to the reference system. In the Vilaine estuary, PGDS polymorphism could be related to pesticide stress.
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Betaína-Homocisteína S-Metiltransferase/genética , Creatina Quinase/genética , Linguado/genética , Gliceraldeído-3-Fosfato Desidrogenases/genética , Oxirredutases Intramoleculares/genética , Lipocalinas/genética , Polimorfismo de Nucleotídeo Único , Animais , Oceano Atlântico , Monitoramento Ambiental , Linguado/crescimento & desenvolvimento , França , Frequência do Gene , Estresse FisiológicoRESUMO
To improve transport of vaccine-loaded nanoparticles, the phage display technology was used to identify novel lead peptides targeting human M cells. Using an in vitro model of the human follicle-associated epithelium (FAE) which contains both Caco-2 and M cells, a T7 phage display library was screened for its ability either to bind the apical cell surface of or to undergo transcytosis across Caco-2 cells or FAE. The selection for transcytosis across both enterocytes and FAE identified three different peptide sequences (CTGKSC, PAVLG and LRVG) with high frequency. CTGKSC and LRVG sequences enhanced phage transport across M-like cells. When polymeric nanoparticles were grafted with the sequences CTGKSC and LRVG, their transport by FAE was significantly enhanced. These peptides could therefore be used to enhance the transport of vaccine-loaded nanoparticles across the intestinal mucosal barrier.
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Sistemas de Liberação de Medicamentos , Nanopartículas , Peptídeos/metabolismo , Vacinas/farmacocinética , Administração Oral , Bacteriófago T7 , Transporte Biológico , Células CACO-2 , Células Epiteliais/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Ligantes , Biblioteca de Peptídeos , Peptídeos/química , Polímeros/química , Análise de Sequência de ProteínaRESUMO
Hydrothermal vent conditions are particular and organisms living in these environments may have developed detoxification mechanisms and/or genetic adaptations. In particular, physico-chemical conditions are thought to generate reactive oxygen species, highly toxic for organisms. The enzyme superoxide dismutase constitutes the first line of defense against oxidative damage. To improve our understanding of the environmental impacts exerted on the vent organisms, we have characterized the two manganese superoxide dismutase cDNAs (mitochondrial: mMnSOD and cytoplasmic: cMnSOD) of three members of the Bythograeidae (Bythograea thermydron, Cyanagraea praedator and Segonzacia mesatlantica), the only endemic crab family living in hydrothermal vents. In comparison, the isolation of manganese superoxide dismutase cDNAs was also carried out in several littoral crab families. MnSOD signatures were found in both sequences from each species studied, as well as different residues involved in metal coordination and protein activity. The phylogenetic analysis performed confirms the probable ancient duplication that gave rise to the two MnSODs (cMnSOD and mMnSOD). This study describes two potential distinct mMnSOD isoforms presenting particular peptide signals. Nevertheless, no sequence particularity that could support the hypothesis of a genetic adaptation was found in Bythograeidae's MnSODs compared to the other sequences. The mRNA expression analysis performed by real-time PCR on B. thermydron and S. mesatlantica compared to Cancer pagurus and Necora puber revealed a higher cMnSOD and mMnSOD mRNA expression in hydrothermal crabs compared to littoral crabs.
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Braquiúros/enzimologia , Filogenia , RNA Mensageiro/metabolismo , Superóxido Dismutase/metabolismo , Sequência de Aminoácidos , Animais , Dados de Sequência Molecular , RNA Mensageiro/genética , Superóxido Dismutase/genéticaRESUMO
The discovery of endogenous pararetroviral sequences (EPRVs) has had a deep impact on the approaches needed for diagnosis, taxonomy, safe movement of germplasm and management of diseases caused by pararetroviruses. In this article, we illustrate this through the example of yam (Dioscorea spp.) badnaviruses. To enable progress, it is first necessary to clarify the taxonomical status of yam badnavirus sequences. Phylogeny and pairwise sequence comparison of 121 yam partial reverse transcriptase sequences provided strong support for the identification of 12 yam badnavirus species, of which ten have not been previously named. Virus prevalence data were obtained, and they support the presence of EPRVs in D. rotundata, but not in D. praehensilis, D. abyssinica, D. alata or D. trifida. Five yam badnavirus species characterised by a wide host range seem to be of African origin. Seven other yam badnavirus species with a limited host range are probably of Asian-Pacific origin. Recombination under natural circumstances appears to be rare. Average values of nucleotide intra-species genetic distances are comparable to data obtained for other RNA and DNA virus families. The dispersion scenarios proposed here, combined with the fact that host-switching events appear common for some yam badnaviruses, suggest that the risks linked to introduction via international plant material exchanges are high.
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Badnavirus/classificação , Dioscorea/virologia , Ecossistema , Doenças das Plantas/virologia , África , América , Sudeste Asiático , Austrália , Badnavirus/enzimologia , Badnavirus/genética , Dioscorea/classificação , Variação Genética , Melanesia , Dados de Sequência Molecular , Filogenia , DNA Polimerase Dirigida por RNA/genética , Recombinação Genética , Proteínas Virais/genéticaRESUMO
A 38-year-old woman presented with a pronounced increase in symptoms and proliferation of urticaria pigmentosa (UP) after acute psychological stress, which was quantified using the Spielberger's State-Trait Anxiety Inventory. Immunohistochemical examination of a skin biopsy from a new UP lesion showed a large number of activated mast cells expressing corticotrophin-releasing factor receptor-1 (CRF-R1) and there was high serum CRF. This is the first documented report to our knowledge of UP worsening associated with acute stress, possibly through activation of skin mast-cell CRF-R1.