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1.
Food Environ Virol ; 16(1): 14-24, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38184502

RESUMO

In the field of chemical engineering and water treatment, the study of viruses, included surrogates, is well documented. Often, surrogates are used to study viruses and their behavior because they can be produced in larger quantities in safer conditions and are easier to handle. In fact, surrogates allow studying microorganisms which are non-infectious to humans but share some properties similar to pathogenic viruses: structure, composition, morphology, and size. Human noroviruses, recognized as the leading cause of epidemics and sporadic cases of gastroenteritis across all age groups, may be mimicked by the Tulane virus. The objectives of this work were to study (i) the ultrafiltration of Tulane virus and norovirus to validate that Tulane virus can be used as a surrogate for norovirus in water treatment process and (ii) the retention of norovirus and the surrogate as a function of water quality to better understand the use of the latter pathogenic viruses. Ultrafiltration tests showed significant logarithmic reduction values (LRV) in viral RNA: around 2.5 for global LRV (i.e., based on the initial and permeate average concentrations) and between 2 and 6 for average LRV (i.e., retention rate considering the increase of viral concentration in the retentate), both for norovirus and the surrogate Tulane virus. Higher reduction rates (from 2 to 6 log genome copies) are obtained for higher initial concentrations (from 101 to 107 genome copies per mL) due to virus aggregation in membrane lumen. Tulane virus appears to be a good surrogate for norovirus retention by membrane processes.


Assuntos
Gastroenterite , Norovirus , Humanos , Norovirus/genética , Ultrafiltração , RNA Viral/genética , Água do Mar , Inativação de Vírus
3.
J Mycol Med ; 30(3): 100985, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32418638

RESUMO

Aspergillus fumigatus can cause a wide range of diseases, from hypersensitivity to invasive infection. Invasive disease usually occurs in severely immunocompromised patients with deep and prolonged neutropenia. It is a less well-recognized complication in critically ill patients without traditional risk factors. We describe a case of early invasive pulmonary aspergillosis (IPA) secondary to Legionella pneumophila serogroup 1 pneumonia in a patient on an intensive care unit (ICU). In addition to commonly accepted risk factors for IPA in ICU patients, we hypothesis that L. pneumophilia pneumonia could enhance this type of infection. We also reviewed all published cases of coinfection with L. pneumophila and A. fumigatus to assess whether Legionnaires' disease could be a risk factor for IPA.


Assuntos
Estado Terminal , Aspergilose Pulmonar Invasiva/complicações , Aspergilose Pulmonar Invasiva/diagnóstico , Doença dos Legionários/complicações , Doença dos Legionários/diagnóstico , Idoso , Aspergillus fumigatus/isolamento & purificação , Diagnóstico Diferencial , França , Humanos , Unidades de Terapia Intensiva , Aspergilose Pulmonar Invasiva/microbiologia , Legionella pneumophila/isolamento & purificação , Doença dos Legionários/microbiologia , Masculino
4.
Clin Genet ; 93(4): 891-898, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29251775

RESUMO

The main objective of our study was to explore whether, and to what extent, genetic counselors' characteristics impact on their tasks in practice. Specifically, we explored the complementariness between genetic counselors and medical geneticists and therefore looked at the most relevant tasks of genetic counselors, according to genetic counselors themselves and according to the medical geneticists they work with. A total of 104 genetic counselors and 29 medical geneticists from 15 countries completed a purposefully designed questionnaire. Results showed that most genetic counselors in Europe perform similar tasks, irrespective of their backgrounds. When looking at the factors influencing genetic counselors' roles data showed that the type of tasks performed by genetic counselors is associated with the years of experience in the field, not with their background or education. Of particular interest was the consensus between genetic counselors and medical geneticists regarding the genetic counselor's role. Not surprisingly, tasks with more psychosocial implications were seen as genetic counselors' eligibility while tasks with more medical implications were seen as medical geneticists' attribution. Our study shows that most genetic counselors work in tune with international recommendations and seem to be supportive of multidisciplinary teams. Corroborating our data with previous research, we discuss potential implications for practice and training in genetic counseling.


Assuntos
Conselheiros/normas , Aconselhamento Genético/normas , Genética Médica/educação , Preceptoria/normas , Europa (Continente) , Genética Médica/normas , Humanos
5.
Rev Pneumol Clin ; 72(6): 377-379, 2016 Dec.
Artigo em Francês | MEDLINE | ID: mdl-27810245

RESUMO

INTRODUCTION: High-risk pulmonary embolism (PE) is associated with high mortality rate (>50%). In some cases, diagnosis of PE remains a challenge with atypical presentations like in this case report with a PE revealed by status epilepticus. CASE REPORT: We report the case of a 40-year-old man without prior disease, hospitalized in ICU for status epilepticus. All paraclinical examinations at admission did not show any significant abnormalities (laboratory tests, cardiologic and neurological investigations). On day 1, he presented a sudden circulatory collapse and echocardiography showed right intra-auricular thrombus. He was treated by thrombolysis and arteriovenous extracorporeal membrane oxygenation. After stabilization, computed tomography showed severe bilateral PE. He developed multi-organ failure and died 4days after admission. CONCLUSIONS: Pulmonary embolism revealed by status epilepticus has rarely been reported and is associated with poor prognosis. Physicians should be aware and think of the possibility of PE in patients with status epilepticus without any history or risk factors of seizure and normal neurological investigations.


Assuntos
Embolia Pulmonar/diagnóstico , Estado Epiléptico/diagnóstico , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Embolia Pulmonar/complicações , Embolia Pulmonar/patologia , Índice de Gravidade de Doença , Estado Epiléptico/complicações
6.
Gynecol Obstet Fertil ; 44(4): 211-7, 2016 Apr.
Artigo em Francês | MEDLINE | ID: mdl-27032759

RESUMO

INTRODUCTION: Trisomy 21 (T21) is the most common chromosomal abnormality and one of the main causes of intellectual disability. The tumor profile of T21 patients is characterized by the low frequency of solid tumors including breast cancer. METHODS: The objective of this work was to analyze the literature to find possible clues for the low frequency of breast cancer in T21 persons with a focus on one hand to the various risks and protective factors against breast cancer for women T21, and on the other hand to changes in the expression of different genes located on chromosome 21. RESULTS: T21 women have hormonal and societal risk factors for breast cancer: frequent nulliparity, lack of breastfeeding, physical inactivity and high body mass index. The age of menopause, earlier in T21 women, has a modest protective effect against breast cancer. The low rate of breast tumors in T21 women is probably mainly linked to the reduced life expectancy compared to the general population (risk of death before the age of onset of the majority of breast cancers) and the presence of a third chromosome 21, characterizing the disease. It might lead to the increased expression of a number of genes contributing directly or undirectly to tumor suppression, decreased tumor angiogenesis and increased cell apoptosis. Moreover, changes in the mammary stroma of persons T21 could have an inhibitory role on the development of breast tumors. CONCLUSION: The low frequency of breast cancers for T21 patients may not only be explained by hormonal and societal factors, but also by genetic mechanisms which could constitute an interesting axis of research in breast cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Síndrome de Down/genética , Adolescente , Adulto , Idoso , Criança , Cromossomos Humanos Par 21 , Feminino , Humanos , Pessoa de Meia-Idade
7.
J Community Genet ; 7(2): 107-18, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26452349

RESUMO

The need for appropriately trained genetic counsellors to support genetic healthcare is now acknowledged. However, while programmes for education of genetic counsellors exist in a number of countries, these do not conform to any specific international standards. As genetic techniques, educational standards and professional standards have been evolved, and with increasing mobility of genetic counsellors, it is of great importance to have some comparison of education and training between different countries. This systematic review was conducted to determine the components of educational programmes for genetic counsellors worldwide that have been published in peer-reviewed literature. Databases were searched for studies published in English from 2000 to 2014 related to the topic. We identified 406 potential papers, of these, 11 studies met the inclusion criteria. The findings indicate that, in most cases, the theoretical components of genetic counsellor programmes conform to the recommendations and requirements of relevant professional bodies. However, clinical preparation of genetic counsellors in real-life professional practice settings seems to be less well addressed as this is essential to ensure genetic counsellors are able to provide safe patient care after graduation. Further work to gain agreement internationally on genetic counsellor education is needed.

8.
J Genet Couns ; 22(6): 844-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23689926

RESUMO

The profession of genetic counseling in France was recognized in 2004, based on the recommendations of a mandate commissioned by the Health Minister to explore the medical demographics of France. The report predicted a shortage of health professionals in the field of genetics, particularly in light of the rapid development of molecular testing. Development of the profession was supported by a legal framework, and today 107 genetic counselors have graduated from the specific educational program which awards the Professional Master's Degree of Human Pathology, entitled Master in Genetic Counseling and Predictive Medicine. Here we will trace the development of the profession in France and review the demographic characteristics of the students and genetic counselors practicing the profession today.


Assuntos
Escolha da Profissão , Aconselhamento Genético , Currículo , Educação Profissionalizante/organização & administração , França
9.
J Gen Virol ; 87(Pt 12): 3763-3771, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17098996

RESUMO

Transgenic mice expressing the prion protein (PrP) of species affected by transmissible spongiform encephalopathies (TSEs) have recently been produced to facilitate experimental transmission of these diseases by comparison with wild-type mice. However, whilst wild-type mice have largely been described for the discrimination of different TSE strains, including differentiation of agents involved in bovine spongiform encephalopathy (BSE) and scrapie, this has been only poorly described in transgenic mice. Here, two ovine transgenic mouse lines (TgOvPrP4 and TgOvPrP59), expressing the ovine PrP (A136 R154 Q171) under control of the neuron-specific enolase promoter, were studied; they were challenged with brainstem or spinal cord from experimentally BSE-infected sheep (AA136 RR154 QQ171 and AA136 RR154 RR171 genotypes) or brainstem from cattle BSE and natural sheep scrapie. The disease was transmitted successfully from all of these sources, with a mean of approximately 300 days survival following challenge with material from two ARQ-homozygous BSE-infected sheep in TgOvPrP4 mice, whereas the survival period in mice challenged with material from the ARR-homozygous BSE-infected sheep was 423 days on average. It was shown that, in the two ovine transgenic mouse lines, the Western blot characteristics of protease-resistant PrP (PrP(res)) were similar, whatever the BSE source, with a low apparent molecular mass of the unglycosylated glycoform, a poor labelling by P4 monoclonal antibody and high proportions of the diglycosylated form. With all BSE sources, but not with scrapie, florid plaques were observed in the brains of mice from both transgenic lines. These data reinforce the potential of this recently developed experimental model for the discrimination of BSE from scrapie agents.


Assuntos
Encefalopatia Espongiforme Bovina/transmissão , Proteínas PrPC/genética , Scrapie/transmissão , Animais , Anticorpos Monoclonais/imunologia , Encéfalo/patologia , Tronco Encefálico , Bovinos , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida , Encefalopatia Espongiforme Bovina/patologia , Immunoblotting , Camundongos , Camundongos Transgênicos , Peso Molecular , Proteínas PrPC/química , Proteínas PrPC/metabolismo , Proteínas PrPSc/imunologia , Proteínas PrPSc/isolamento & purificação , Proteínas PrPSc/metabolismo , Scrapie/patologia , Ovinos , Medula Espinal , Análise de Sobrevida
10.
Biopolymers ; 82(4): 399-404, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16421855

RESUMO

Surface enhanced resonance Raman scattering (SERRS) is shown to be a satisfying method to study the interaction between DNA and ruthenium complexes [Ru(bpy)(2)(Hcmbpy)][PF(6)](2), where Hcmbpy = 4-carboxy-4'-methyl-2,2'-bipyridine. Such metallic complexes are known for their fluorescence properties. To validate this spectroscopic approach we have checked that i) at a given lambda(ex), silver colloidal SERRS spectra of Ru complexes closely resemble resonance Raman spectra in aqueous solutions, intensity excepted, and ii) the DNA fragments are not altered when they are adsorbed on the Ag nanoparticles surface. This investigation shows that the intensity of the Ru complexes SERRS spectra is reduced in the presence of DNA, in particular for the specific bands assigned to the Hcmbpy ligand. This collapse demonstrates that the Ru complexes bind DNA through the Hcmbpy moiety, and intercalation is suggested as the binding mode. The DNA binding by the enantiopure Ru complexes (Delta or Lambda) is more efficient than by the racemic complexes.


Assuntos
2,2'-Dipiridil/química , DNA/química , Compostos Organometálicos/química , Rutênio/química , Análise Espectral Raman/métodos , Sítios de Ligação , DNA/metabolismo , Estrutura Molecular , Compostos Organometálicos/metabolismo , Estereoisomerismo
11.
J Theor Biol ; 206(3): 323-6, 2000 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-10988018

RESUMO

A correlation function that compares each base in a DNA sequence to its various neighbours and which is subsequently processed by Fourier and wavelet transforms has been developed. The procedure has been applied to sequences from the human chromosome 22, to nef genes from various HIV clones and to myosin heavy chain DNA. It permits to readily visualize regular features in DNA which are related to the stability of heteroduplexes formed upon strand slippage.


Assuntos
Análise de Fourier , Análise de Sequência de DNA/métodos , Animais , Cromossomos Humanos Par 22 , Produtos do Gene nef , Genes Virais , HIV/genética , Humanos , Cadeias Pesadas de Miosina/genética , Produtos do Gene nef do Vírus da Imunodeficiência Humana
12.
Arch Mal Coeur Vaiss ; 92(11 Suppl): 1617-26, 1999 Nov.
Artigo em Francês | MEDLINE | ID: mdl-10598244

RESUMO

The aims of myocardial revascularisation are to treat angina, reduce ischaemia and improve life expectancy. Patients with multivessel disease have a poor prognosis, especially when the lesions are proximal, when the preseptal left anterior descending artery is involved and when left ventricular dysfunction is present. In this particular group of patients, coronary bypass surgery has been shown to improve 10 year survival. Coronary angioplasty has been compared with surgical treatment in many clinical trials. The medium-term survival is the same in both groups, but with a higher number of repeat procedures except in diabetic patients in whom mortality is higher after angioplasty. The use of coronary stents should reduce the number of post-angioplasty procedures. Constant technical improvements, the introduction of surgery without cardiopulmonary bypass, combined revascularisation procedures, new antiplatelet drugs, the absence of long-term comparative results, all this results in a personalized choice of revascularisation procedure based on the overall clinical and angiography features of each particular case.


Assuntos
Angioplastia Coronária com Balão , Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Doença das Coronárias/terapia , Revascularização Miocárdica/métodos , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Prognóstico , Stents , Análise de Sobrevida , Resultado do Tratamento
13.
Eur J Biochem ; 265(3): 1032-42, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10518799

RESUMO

The solution structures of d(GAAAACGTTTTC)2 and of its methylated derivative d(GAAAAMe5CGTTTTC)2 have been determined by NMR and molecular modelling in order to examine the impact of cytosine methylation on the central CpG conformation. Detailed 1H NMR and 31P NMR investigation of the two oligomers includes quantitative NOESY, 2D homonuclear Hartmann-Hahn spectroscopy, double-quantum-filtered COSY and heteronuclear 1H-31P correlation. Back-calculations of NOESY spectra and simulations of double-quantum-filtered COSY patterns were performed to gain accurate information on interproton distances and sugar phase angles. Molecular models under experimental constraints were generated by energy minimization by means of the molecular mechanics program JUMNA. The MORASS software was used to iteratively refine the structures obtained. After methylation, the oligomer still has a B-DNA conformation. However, there are differences in the structural parameters and the thermal stability as compared to the unmethylated molecule. Careful structural analysis shows that after methylation CpG departs from the usual conformation observed in other ACGT tetramers with different surroundings. Subtle displacements of bases, sugars and backbone imposed by the steric interaction of the two methyl groups inside the major groove are accompanied by severe pinching of the minor groove at the C-G residues.


Assuntos
Oligodesoxirribonucleotídeos/química , 5-Metilcitosina , Sequência de Bases , Ilhas de CpG , Citosina/análogos & derivados , Citosina/química , Espectroscopia de Ressonância Magnética/métodos , Metilação , Modelos Moleculares , Conformação de Ácido Nucleico , Soluções
14.
Eur J Biochem ; 261(3): 722-33, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10215889

RESUMO

The determination of the solution structure of two self-complementary oligomers d(ATGACGTCAT)2 (CG10) and d(GAAAACGTTTTC)2 (CG12), both containing the 5'-pur-ACGT-pyr-3' sequence, is reported. The impact of the base context on the conformation of the central CpG site has been examined by a combined approach of: (a) 2D 1H-NMR and 31P-NMR; (b) molecular mechanics under experimental constraints; (c) back-calculations of NOESY spectra and iterative refinements of distances; and (d) 3D-homology search of the central tetrad ACGT within the complete oligonucleotides. A full NMR study of each fragment is achieved by means of standard 2D experiments: NOESY, 2D homonuclear Hartmann-Hahn spectroscopy, double-quantum-filtered COSY and heteronuclear 1H-31P correlation. Sugar phase angle, epsilon-zeta difference angle and NOE-derived distances are input as experimental constraints to generate molecular models by energy minimization with the help of jumna. The morass program is used to iteratively refine the structures obtained. The similarity of the two ACGTs within the whole oligonucleotides is investigated. Both the decamer and the dodecamer adopt a B-like DNA conformation. However, the helical parameters within this conformational type are significantly different in CG12 and CG10. The central CpG step conformation is not locked by its nearest environment (5'A and 3'T) as seen from the structural analysis of ACGT in the two molecules. In CG12, despite the presence of runs of A-T pairs, CpG presents a high twist of 43 degrees and a sugar phase at the guanine of about 180 degrees, previously observed in other ACGT-containing-oligomers. Conversely, ACGT in CG10 exhibits strong inclinations, positive rolls, a flat profile of sugar phase, twist and glycosidic angles, as a result of the nucleotide sequence extending beyond the tetrad. The structural specificity of CG10 and its flexibility (as reflected by its energy) are tentatively related to the process of recognition of the cyclic AMP response element by its cognate protein.


Assuntos
Desoxirribonucleotídeos/química , Conformação de Ácido Nucleico , Sequência de Bases , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Homologia de Sequência do Ácido Nucleico
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