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1.
J Cancer Educ ; 39(4): 353-359, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38411867

RESUMO

Deaf, deafblind, and hard of hearing (DDBHH) individuals experience barriers to accessing cancer screening, including ineffective patient-physician communication when discussing screening recommendations. For other underserved communities, culturally and linguistically aligned community health navigators (CHNs) have been shown to improve cancer screening and care. A needs assessment study was conducted to identify barriers and gather recommendations for CHN training resources. A community-based participatory needs assessment was conducted from May 2022 to June 2022 using three focus groups. Eight were cancer survivors, six advocates/navigators, and three clinicians. All questions were semi-structured and covered screening barriers, observations or personal experiences, perceived usefulness of having a CHN to promote cancer screening adherence, and training resources that may be useful to American Sign Language (ASL)-proficient CHNs, who are also culturally and linguistically aligned. Out of 20 focus group participants, seven self-identified as persons of color. Data highlighted systemic, attitudinal, communication, and personal-level barriers as recurrent themes. The most frequently cited barrier was access to training that supports the role and competencies of CHNs, followed by cultural considerations, access to cancer guidelines in ASL, dialect diversity in sign language, and the health system itself. Unaddressed barriers can contribute to health disparities, such as lower preventive cancer screening rates amongst DDBHH individuals. The next step is to translate recommendations into actionable tasks for DDBHH CHN training programs. As a result, CHNs will be well-equipped to help DDBHH individuals navigate and overcome their unique barriers to cancer screening and healthcare access.


Assuntos
Agentes Comunitários de Saúde , Pesquisa Participativa Baseada na Comunidade , Detecção Precoce de Câncer , Grupos Focais , Língua de Sinais , Humanos , Feminino , Masculino , Pessoas com Deficiência Auditiva/psicologia , Adulto , Pessoa de Meia-Idade , Navegação de Pacientes , Barreiras de Comunicação , Avaliação das Necessidades , Neoplasias/diagnóstico , Neoplasias/prevenção & controle , Acessibilidade aos Serviços de Saúde , Surdez/diagnóstico
2.
Front Cell Infect Microbiol ; 13: 1233148, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37671145

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV; family Nairoviridae) is a tick-borne pathogen that frequently causes lethal disease in humans. CCHFV has a wide geographic distribution, and cases have been reported in Africa, Asia, the Middle East, and Europe. Availability of a safe and efficacious vaccine is critical for restricting outbreaks and preventing disease in endemic countries. We previously developed a virus-like replicon particle (VRP) vaccine that provides complete protection against homologous and heterologous lethal CCHFV challenge in mice after a single dose. However, the immune responses induced by this vaccine are not well characterized, and correlates of protection remain unknown. Here we comprehensively characterized the kinetics of cell-mediated and humoral immune responses in VRP-vaccinated mice, and demonstrate that they predominantly target the nucleoprotein (NP). NP antibodies are not associated with protection through neutralizing activity, but VRP vaccination results in NP antibodies possessing Fc-mediated antibody effector functions, such as complement activation (ADCD) and antibody-mediated cellular phagocytosis (ADCP). This suggests that Fc-mediated effector functions may contribute to this vaccine's efficacy.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo , Vacinas , Humanos , Animais , Camundongos , Vacinação , Anticorpos , Nucleoproteínas , Linfócitos T
3.
Nano Lett ; 22(5): 1929-1936, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35176209

RESUMO

The 1T polytype of TaS2 has been studied extensively as a strongly correlated system. As 1T-TaS2 is thinned toward the 2D limit, its phase diagram shows significant deviations from that of the bulk material. Optoelectronic maps of ultrathin 1T-TaS2 have indicated the presence of nonequilibrium charge density wave phases within the hysteresis region of the nearly commensurate (NC) to commensurate (C) transition. We perform scanning tunneling microscopy on exfoliated ultrathin flakes of 1T-TaS2 within the NC-C hysteresis window, finding evidence that the observed nonequilibrium phases consist of intertwined, irregularly shaped NC-like and C-like domains. After applying lateral electrical signals to the sample, we image changes in the geometric arrangement of the different regions. We use a phase separation model to explore the relationship between electronic inhomogeneity present in ultrathin 1T-TaS2 and its bulk resistivity. These results demonstrate the role of phase competition morphologies in determining the properties of 2D materials.

4.
New Microbes New Infect ; 34: 100658, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32194964

RESUMO

Bacteria of the genus Gordonia are rarely involved in human infections. We report here the case of a 30-year-old man from Guinea Buissau with mycetoma of the foot. 16S DNA sequencing after surgical biopsy identified Gordonia westfalica. To our knowledge, this is the first report of human infection caused by G. westfalica.

5.
Eur J Clin Microbiol Infect Dis ; 39(3): 559-567, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31758438

RESUMO

We assessed the performance of the VITEK® MS IVD V3.0 matrix-assisted laser desorption ionization - time of flight mass spectrometry (MALDI-ToF MS) V3.0 database for the identification of Nocardia spp. as compared with targeted DNA sequencing. A collection of 222 DNA sequence-defined Nocardia spp. strains encompassing 18 different species present or not in the database was tested. Bromocresol purple agar (BCP) and Columbia agar +5% sheep's blood (COS) culture media were used together with two different preparation steps: direct smear and a "3 attempts" procedure that covered (1) spotting of an extract, (2) new spotting of the same extract, and (3) spotting of a new extract. The direct smear protocol yielded low correct identification rates (≤ 15% for both media) whereas protein extraction yielded correct identification results (> 67% regardless of the media used.). The use of 2 additional attempts using repeat or new extracts increased correct identification rates to 87% and 91% for BCP and COS, respectively. When using the 3 attempts procedure, the best identification results, independent of media types, were obtained for N. farcinica and N. cyriacigeorgica (100%). Identification attempts 2 and 3 allowed to increase the number of correct identifications (BCP, +20%; COS, +13%). The enhancement in performance during attempts 2 and 3 was remarkable for N. abscessus (81% for both media) and low prevalence species (BCP, 70%; COS, 85%). Up to 3.4% and 2.4% of the strains belonging to species present in the database were misidentified with BCP and COS media, respectively. In 1.9% of the cases for BCP and 1.4% for COS, these misidentifications concerned a species belonging to the same phylogenetic complex. Concerning strains that are not claimed in the V3.0 database, N. puris and N. goodfellowi generated "No identification" results and 100% of the strains belonging to N. arthritidis, N.cerradoensis, and N. altamirensis yielded a misidentification within the same phylogenetic complex. Vitek® MS IVD V3.0 is an accurate and useful tool for identification of Nocardia spp.


Assuntos
Técnicas Bacteriológicas , Bases de Dados Factuais , Nocardiose/diagnóstico , Nocardiose/microbiologia , Nocardia/classificação , Algoritmos , Proteínas de Bactérias/isolamento & purificação , Humanos , Nocardia/metabolismo , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Fluxo de Trabalho
6.
Clin Microbiol Infect ; 25(4): 489-495, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29933049

RESUMO

OBJECTIVES: Nocardia, a Gram-positive bacterium, is responsible for rare and severe infections. Accurate microbiological data are essential to guide antibiotic treatment. Our primary objective was to describe species identification and results of antimicrobial susceptibility testing (AST) for Nocardia isolates analysed over a 6-year period. Secondary objectives were to study temporal trends in species distribution and AST results. METHODS: We retrospectively analysed results from Nocardia isolates sent between January 2010 and December 2015 to a French laboratory dedicated to Nocardia (Observatoire Français des Nocardioses). Species identification was obtained by amplification and sequencing of a 600-bp fragment of the 16S rRNA gene (for all isolates) and of hsp65 (when required). AST was performed using disk diffusion. RESULTS: We included 793 Nocardia isolates, mostly from the lungs (53.8%). The most frequent species were Nocardia farcinica (20.2%), Nocardia abscessus complex (19.9%) and Nocardia nova complex (19.5%). The proportion of N. farcinica increased significantly over time from 13% in 2010 to 27.6% in 2014. Linezolid, amikacin, trimethoprim-sulfamethoxazole, minocycline and imipenem were the most frequently identified active antibiotics with, respectively, 0% (0/734), 2.9% (21/730), 5.4% (40/734), 9.4% (69/734) and 19.5% (143/732) of isolates not susceptible. Nocardia farcinica was frequently not susceptible to cefotaxime (118/148, 79.7% of the isolates), but only about 5% of Nocardia cyriacigeorgica and N. abscessus complex isolates were not susceptible to cefotaxime. CONCLUSIONS: In this first epidemiological study of Nocardia isolated from human samples in France, N. farcinica was the species most frequently identified and its prevalence increased over time.


Assuntos
Antibacterianos/uso terapêutico , Nocardiose/tratamento farmacológico , Nocardiose/epidemiologia , Nocardia/classificação , Nocardia/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Amicacina/uso terapêutico , Proteínas de Bactérias/genética , Criança , Pré-Escolar , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Feminino , França/epidemiologia , Humanos , Imipenem/uso terapêutico , Linezolida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Minociclina/uso terapêutico , Nocardia/genética , Nocardiose/microbiologia , RNA Ribossômico 16S/genética , Estudos Retrospectivos , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Adulto Jovem
7.
Biomed Res Int ; 2018: 7314054, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29888277

RESUMO

This study aims at genetic characterization and phylogenetic relationships of Nocardia brasiliensis focusing by using housekeeping rrs, hsp65, and sodA genes. N. brasiliensis is the species responsible for 80% of cases of actinomycetoma, one form of cutaneous nocardiosis which occurs mainly in tropical regions reaching immunocompetent patients in which the disease can lead to amputation. We analyze 36 indigenous cases of N. brasiliensis that happened in France. Phylogenetic analysis targeting rrs gene showed no robustness at phylogenetic nodes level. However, the use of a concatenation of hsp65 and sodA genes showed that the tested strains surprisingly ranked in 3 well-defined genotypes. Genotypes 2 and 3 were phylogenetically closer to each other and both diverged from genotype 1 sustained by a high bootstrap of 81%. This last genotype hosts all the cases of pulmonary forms (3), the sole cerebral form, and almost all the cases of immunocompromised patients (3 out of 4). Moreover, excepting one of them, all the strains belonging to this group present a susceptibility to imipenem which is not the case in the other genotypes that rarely count among them strains being susceptible to this drug. The haplotype diversity (Hd) of hsp65 (0.927) and sodA (0.885) genes was higher than that of rrs (0.824). For this gene, we obtained 16 polymorphic sites whereas, for hsp65 and sodA genes, up to 27 and 29 were identified, respectively. This study reveals that these two genes have an important genetic discriminatory power for the evaluation of the intraspecies genetic variability of N. brasiliensis and they may be useful for identification purposes at species level. This study also reveals the possible existence of a new species harbored by genotype 1.


Assuntos
Proteínas de Bactérias/genética , Variação Genética , Nocardiose/genética , Superóxido Dismutase-1/genética , França/epidemiologia , Humanos , Nocardia/genética , Nocardia/patogenicidade , Nocardiose/epidemiologia , Nocardiose/microbiologia , Nocardiose/patologia , Filogenia
8.
J Mycol Med ; 28(3): 531-537, 2018 Sep.
Artigo em Francês | MEDLINE | ID: mdl-29773433

RESUMO

Nocardial brain abscess is often occurring in immunocompromised patients. It is uncommon in immunocompetent individuals. Here, the authors describe a case of cerebral and pulmonary nocardiosis mimicking a metastatic tumor in an apparently health 40-year-old Algerian male. The patient presented multiple brain abscess revealed by inaugural epileptic seizure. He was afebrile and presented with left hemiparesis. Staging imaging showed a nodular lung lesion in the apical segment of the right lower lobe. The patient underwent double craniotomy for resection of the lesion. Culture of the resected specimen isolated Nocardia abscessus. The patient was initially started on intravenous trimethoprim-sulfamethoxazole and intravenous amikacine. He was switched to oral trimethoprim-sulfamethoxazole. He finished seven months of antibiotic therapy with a good clinical response. Imaging revealed reduction in the brain abscess and a complete resolution of the lung lesion. Cotrimoxazole was stopped after twelve months of therapy. After two years, the health status of our patient improves day after day. He is however regularly under medical supervision for control exams.


Assuntos
Abscesso Encefálico/diagnóstico , Pneumopatias Fúngicas/diagnóstico , Nocardiose/diagnóstico , Nocardia/isolamento & purificação , Adulto , Argélia , Abscesso Encefálico/microbiologia , Humanos , Imunocompetência , Pneumopatias Fúngicas/imunologia , Masculino , Nocardiose/imunologia
9.
New Microbes New Infect ; 19: 96-116, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28794885

RESUMO

Currently for bacterial identification and classification the rrs gene encoding 16S rRNA is used as a reference method for the analysis of strains of the genus Nocardia. However, it does not have enough polymorphism to differentiate them at the species level. This fact makes it necessary to search for molecular targets that can provide better identification. The sodA gene (encoding the enzyme superoxide dismutase) has had good results in identifying species of other Actinomycetes. In this study the sodA gene is proposed for the identification and differentiation at the species level of the genus Nocardia. We used 41 type species of various collections; a 386 bp fragment of the sodA gene was amplified and sequenced, and a phylogenetic analysis was performed comparing the genes rrs (1171 bp), hsp65 (401 bp), secA1 (494 bp), gyrB (1195 bp) and rpoB (401 bp). The sequences were aligned using the Clustal X program. Evolutionary trees according to the neighbour-joining method were created with the programs Phylo_win and MEGA 6. The specific variability of the sodA genus of the genus Nocardia was analysed. A high phylogenetic resolution, significant genetic variability, and specificity and reliability were observed for the differentiation of the isolates at the species level. The polymorphism observed in the sodA gene sequence contains variable regions that allow the discrimination of closely related Nocardia species. The clear specificity, despite its small size, proves to be of great advantage for use in taxonomic studies and clinical diagnosis of the genus Nocardia.


Actualmente, para la identificación y clasificación bacteriana se utiliza como método de referencia la secuenciación el gen rrs que codifica al rRNA16S, en el caso del análisis de cepas del género Nocardia, sin embargo, no tiene el suficiente polimorfismo para diferenciarlas a nivel de especie lo que hace necesaria la búsqueda de blancos moleculares que puedan proporcionar una mejor identificación. El gen sodA (que codifica la enzima superóxido dismutasa) ha tenido buenos resultados en la identificación de especies de otros Actinomicetos. En este estudio se propone para la identificación y diferenciación a nivel de especie del género Nocardia. Se utilizaron 41 especies Tipo de diversas colecciones, se amplificó y secuenció un fragmento de 386 pb del gen sodA y se realizó un análisis filogenético comparando los genes rrs (1171 pb) hsp65(401pb) secA1 (494pb), gyrB (1195pb) y rpoB (401pb), las secuencias fueron alineadas utilizando el programa Clustal X, los árboles evolutivos de acuerdo con el método de "Neighbor-Joining"se hicieron con el programa Phylo_win y Mega 6. Se analizó la variabilidad específica del gen sodA del género Nocardia presentando una alta resolución filogenética, una variabilidad genética importante, especificidad y confiabilidad para la diferenciación de los aislados a nivel de especie. El polimorfismo observado en la secuencia del gen sodA contiene regiones variables que posibilitan la discriminación de especies de Nocardia estrechamente relacionadas, y una clara especificidad, a pesar de su pequeño tamaño, demostrando ser de gran ventaja para utilizarse en estudios taxonómicos y en el diagnóstico clínico del género Nocardia.

10.
J Virol ; 90(18): 8314-27, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27412597

RESUMO

UNLABELLED: The regulation of the interferon type I (IFN-I) response has been shown to rely on posttranslational modification by ubiquitin (Ub) and Ub-like interferon-stimulated gene product 15 (ISG15) to stabilize, or activate, a variety of IFN-I signaling and downstream effector proteins. Unlike Ub, which is almost perfectly conserved among eukaryotes, ISG15 is highly divergent, even among mammals. Since zoonotic viruses rely on viral proteins to recognize, or cleave, ISG15 conjugates in order to evade, or suppress, innate immunity, the impact of ISG15 biodiversity on deISGylating proteases of the ovarian tumor family (vOTU) from nairoviruses was evaluated. The enzymatic activities of vOTUs originating from the Crimean-Congo hemorrhagic fever virus, Erve virus, and Nairobi sheep disease virus were tested against ISG15s from humans, mice, shrews, sheep, bats, and camels, which are mammalian species known to be infected by nairoviruses. This along with investigation of binding by isothermal titration calorimetry illustrated significant differences in the abilities of nairovirus deISGylases to accommodate certain species of ISG15. To investigate the molecular underpinnings of species preferences of these vOTUs, a structure was determined to 2.5 Å for a complex of Erve virus vOTU protease and a mouse ISG15 domain. This structure revealed the molecular basis of Erve virus vOTU's preference for ISG15 over Ub and the first structural insight into a nonhuman ISG15. This structure also revealed key interactions, or lack thereof, surrounding three amino acids that may drive a viral deISgylase to prefer an ISG15 from one species over that of another. IMPORTANCE: Viral ovarian tumor domain proteases (vOTUs) are one of the two principal classes of viral proteases observed to reverse posttranslational modification of host proteins by ubiquitin and interferon-stimulated gene product 15 (ISG15), subsequently facilitating downregulation of IFN-I signaling pathways. Unlike the case with ubiquitin, the amino acid sequences of ISG15s from various species are notably divergent. We illustrate that vOTUs have clear preferences for ISG15s from certain species. In addition, these observations are related to the molecular insights acquired via the first X-ray structure of the vOTU from the Erve nairovirus in complex with the first structurally resolved nonhuman ISG15. This information implicates certain amino acids that drive the preference of vOTUs for ISG15s from certain species.


Assuntos
Nairovirus/enzimologia , Peptídeo Hidrolases/metabolismo , Ubiquitinas/metabolismo , Animais , Cristalografia por Raios X , Humanos , Modelos Moleculares , Nairovirus/fisiologia , Peptídeo Hidrolases/química , Ligação Proteica , Conformação Proteica , Proteólise , Ubiquitinas/química
11.
Virology ; 442(2): 97-100, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23711383

RESUMO

In 2012, an unprecedented number of four distinct, partially overlapping filovirus-associated viral hemorrhagic fever outbreaks were detected in equatorial Africa. Analysis of complete virus genome sequences confirmed the reemergence of Sudan virus and Marburg virus in Uganda, and the first emergence of Bundibugyo virus in the Democratic Republic of the Congo.


Assuntos
Surtos de Doenças , Infecções por Filoviridae/epidemiologia , Filoviridae/genética , Filoviridae/isolamento & purificação , Genoma Viral , Febres Hemorrágicas Virais/epidemiologia , RNA Viral/genética , República Democrática do Congo/epidemiologia , Filoviridae/classificação , Infecções por Filoviridae/virologia , Febres Hemorrágicas Virais/virologia , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA , Uganda/epidemiologia
13.
J Mycol Med ; 22(1): 1-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23177807

RESUMO

BACKGROUND: Mexico has the largest number of clinical cases of actinomycetoma in North and South America. Species originally identified by less specific methods have been recently reclassified as other known species or as new species. OBJECTIVE: To assess, by 16S rRNA gene sequencing and phenotypic methods, the species distribution of 18 human clinical isolates originally identified as N. brasiliensis, some of them isolated between 1947 and 1959 in Mexico City. METHODS: Clinical isolates came from the Hospital General, "Dr. Manuel Gea Gonzalez", and Instituto Nacional de Diagnóstico y Referencia Epidemiológica (INDRE) in Mexico, D.F. The strains used in this study included 15 clinical strains isolated between 1947 and 1959 that were originally identified as N. brasiliensis and three more strains obtained in 2007 identified as Nocardia spp. The isolates were identified genotypically by sequencing the 16S rRNA gene, and their phenotypic profiles were obtained with the API Coryne(®) system. Antibiotic susceptibility patterns were tested according to the protocol of the Comité de l'antibiogramme de la Société française de microbiologie[4]. RESULTS: According to 16S rRNA gene, sequencing were identified among 18 human clinical isolates as Nocardia farcinica (n=11) and Nocardia brasiliensis (n=7). A high number of the strains were susceptible to the majority of the antibiotics tested. The phenotypic profiles of the strains were quite uniform for N. farcinica and some variability was observed for N. brasiliensis strains. CONCLUSION: N. farcinica was the most prevalent species identified. Modern methodologies should be applied in clinical laboratories to accurately identify etiological agents.


Assuntos
Nocardiose/microbiologia , Nocardia/isolamento & purificação , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Genótipo , Humanos , México/epidemiologia , Testes de Sensibilidade Microbiana , Nocardia/classificação , Nocardia/efeitos dos fármacos , Nocardia/genética , Nocardiose/epidemiologia , Fenótipo , Filogenia , RNA Ribossômico 16S/genética
14.
J Clin Microbiol ; 50(8): 2702-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22692743

RESUMO

Matrix-associated laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is a rapid and simple microbial identification method. Previous reports using the Biotyper system suggested that this technique requires a preliminary extraction step to identify Gram-positive rods (GPRs), a technical issue that may limit the routine use of this technique to identify pathogenic GPRs in the clinical setting. We tested the accuracy of the MALDI-TOF MS Andromas strategy to identify a set of 659 GPR isolates representing 16 bacterial genera and 72 species by the direct colony method. This bacterial collection included 40 C. diphtheriae, 13 C. pseudotuberculosis, 19 C. ulcerans, and 270 other Corynebacterium isolates, 32 L. monocytogenes and 24 other Listeria isolates, 46 Nocardia, 75 Actinomyces, 18 Actinobaculum, 11 Propionibacterium acnes, 18 Propionibacterium avidum, 30 Lactobacillus, 21 Bacillus, 2 Rhodococcus equi, 2 Erysipelothrix rhusiopathiae, and 38 other GPR isolates, all identified by reference techniques. Totals of 98.5% and 1.2% of non-Listeria GPR isolates were identified to the species or genus level, respectively. Except for L. grayi isolates that were identified to the species level, all other Listeria isolates were identified to the genus level because of highly similar spectra. These data demonstrate that rapid identification of pathogenic GPRs can be obtained without an extraction step by MALDI-TOF mass spectrometry.


Assuntos
Bactérias Aeróbias/química , Bactérias Aeróbias/classificação , Técnicas Bacteriológicas/métodos , Bactérias Gram-Positivas/química , Bactérias Gram-Positivas/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Sensibilidade e Especificidade , Fatores de Tempo
15.
Eur J Clin Microbiol Infect Dis ; 30(10): 1249-56, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21494911

RESUMO

The spread of multiresistant bacteria increases the need for new antibiotics. The observation that some nucleoside analogues have antibacterial activity led us to further investigate the antimicrobial activity and resistance of zidovudine (AZT). We determined the minimum inhibition concentration (MIC), studied time-kill curves, induced resistant bacteria and sequenced the gene for thymidine kinase. We demonstrate that AZT has a bactericidal effect on some enterobacteria. However, AZT could induce resistance in Escherichia coli. These resistances were associated with various modifications in the thymidine kinase gene. In particular, we observed the presence in this gene of an insertion sequence (IS) similar to IS911 of Shigella dysenteriae in two resistant clones. No cross-resistance with classical antibiotics in strains with modified thymidine kinase gene was observed. Finally, an additive or synergistic activity between AZT and the two aminoglycoside antibiotics amikacin and gentamicin was observed. We demonstrate the bactericidal activity of AZT and show synergy in association with gentamicin. Genetic modifications in resistant bacteria were identified. Our results indicate that AZT could potentially be added in the treatment of infections with enterobacteria or represent the basis for the development of derivatives with better activity and inducing less resistance.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Mutagênicos/farmacologia , Zidovudina/farmacologia , Amicacina/farmacologia , Proteínas de Bactérias/genética , Análise Mutacional de DNA , Farmacorresistência Bacteriana , Sinergismo Farmacológico , Gentamicinas/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Mutação , Análise de Sequência de DNA , Shigella dysenteriae , Staphylococcus aureus/efeitos dos fármacos , Timidina Quinase/genética , Fatores de Tempo
16.
Growth Factors ; 28(3): 149-56, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20102315

RESUMO

Several studies have shown that bone morphogenetic proteins (BMPs) can influence adipogenic and osteogenic cell lineages. We have shown that a peptide derived from BMP-9 (pBMP-9) at 400 ng/ml inhibits the proliferation of preosteoblasts and induces differentiation. We have now determined the effects of pBMP-9 (400 ng/ml) and equimolar concentrations of BMP-2 (100 ng/ml), BMP-9 (84.6 ng/ml) and pBMP-9 (9.04 ng/ml) on human white preadipocytes (HWP). pBMP-9 dose dependently reduced the proliferation of HWP without affecting the number of apoptotic cells. Incubation of the cells for 1 h with BMP-2, BMP-9 or pBMP-9 activated the Smad1/5/8 pathway, while incubation for 7 days in adipocyte differentiation (AD) serum-free medium containing ciglitazone and equimolar concentrations of BMP-2, BMP-9 or pBMP-9 enhanced the levels of mRNA of the adipogenic markers aP2 and adipoQ and increased the number of lipid vesicles. Thus, pBMP-9, like BMP-9, can increase the AD of HWP in AD serum-free medium.


Assuntos
Adipócitos Brancos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Fatores de Diferenciação de Crescimento/farmacologia , Adipócitos Brancos/fisiologia , Adulto , Proteína Morfogenética Óssea 2/farmacologia , Proliferação de Células/efeitos dos fármacos , Feminino , Marcadores Genéticos , Fator 2 de Diferenciação de Crescimento , Humanos , Osteogênese/efeitos dos fármacos , PPAR gama/análise , Peptídeos/farmacologia , Proteínas Smad/efeitos dos fármacos , Tiazolidinedionas/farmacologia
17.
Cytokine Growth Factor Rev ; 20(3): 213-22, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19493693

RESUMO

The bone morphogenetic proteins (BMPs) are cytokines of the transforming growth factor beta family. Some BMPs such as BMP-2 and BMP-7 play a major role in the development of the skeleton and the maintenance of homeostasis during bone remodelling. To date, only BMP-2 and BMP-7 have been approved by the Food and Drug Administration for specific orthopaedic applications. However, due to BMP cost, peptides derived from their knuckle epitope with osteogenic properties have been developed. BMPs are involved in many other biological events, including embryogenesis, angiogenesis and cancer. BMPs therefore have great biomedical potential as osteogenic factors and as anti-cancer agents. This review focuses on the use of BMPs and their derived peptides in biomedical delivery systems and gene therapy.


Assuntos
Proteínas Morfogenéticas Ósseas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Peptídeos/farmacologia , Proteínas Morfogenéticas Ósseas/química , Proteínas Morfogenéticas Ósseas/genética , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Modelos Biológicos , Osteoblastos/citologia , Osteoblastos/metabolismo , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo
18.
Eur J Clin Microbiol Infect Dis ; 28(9): 1105-11, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19449044

RESUMO

The purpose of this study was to evaluate the possibility of using a semi-automated repetitive DNA sequences-based polymerase chain reaction (rep-PCR) for typing Pseudomonas aeruginosa isolates. rep-PCR profiles obtained by the DiversiLab system of 84 P. aeruginosa isolates from distinct epidemiological situations were obtained. rep-PCR groupings were in good agreement with the origin of these isolates. Linked rep-PCR profiles were observed for isolates recovered from a same family of cystic fibrosis (CF) patients, for the etiological agents of clustered cases of nosocomial infections, and for some isolates recovered from a same hospital room. rep-PCR and pulsed-field gel electrophoresis SpeI restricted genomic DNA (PFGE-SpeI) profiles were compared. In a few instances, rep-PCR revealed genetic divergences among isolates of a same group of PFGE-SpeI profiles. These divergences could reflect genetic drifts among closely related isolates, as illustrated by those observed between clinical and environmental isolates of a same group of PFGE-SpeI profiles. The interpretation of such differences will require further studies, but the rep-PCR analysis of P. aeruginosa diversity appeared to be an appropriate method to investigate infra-specific genetic relatedness.


Assuntos
Automação/métodos , Técnicas de Tipagem Bacteriana/métodos , Impressões Digitais de DNA/métodos , Reação em Cadeia da Polimerase/métodos , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , DNA Bacteriano/genética , Humanos , Sequências Repetitivas Dispersas , Epidemiologia Molecular/métodos , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/isolamento & purificação
19.
Ann Biol Clin (Paris) ; 66(5): 499-508, 2008.
Artigo em Francês | MEDLINE | ID: mdl-18957338

RESUMO

Efflux pumps located in the bacterial membranes are responsible for low level resistance to antibiotics, considered not to be relevant in the clinic and thus often neglected. However, these pumps contribute to the emergence of high level antibiotic resistance mechanisms, which are responsible for severe complications during the treatment of infectious diseases. Therefore it is necessary to take into account these pumps while developing novel antibacterial agents. Among these new research strategies, the development of efflux pump inhibitors seems to be an attractive approach to restore the activity of some "classical" antibiotics and to limit the emergence of multiresistant strains associated with hospital-acquired infections. In this review, we focalise on Staphylococcus aureus efflux pumps and their potential inhibitors.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Proteínas de Membrana Transportadoras , Staphylococcus aureus/efeitos dos fármacos , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Transporte Biológico Ativo , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana/fisiologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Farmacorresistência Bacteriana Múltipla/fisiologia , Humanos , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Staphylococcus aureus/metabolismo , Staphylococcus aureus/fisiologia
20.
Biomed Mater Eng ; 17(4): 199-208, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17611295

RESUMO

In the last few years, regulations for biomolecule production, and especially for extraction and purification of animal molecules such as collagen, have been reinforced to ensure the sanitary safety of the materials. To be authorized to market biomaterials based on collagen, manufacturers now have to prove that at least one step of their process is described in guidelines to inactivate prion, viruses, and bacteria. The present study focuses on the inactivation step performed during the extraction and purification of porcine type I atelocollagen. We chose to determine the reduction factor of a 1 M NaOH step on porcine parvovirus and four bacterial strains inactivation. During the extraction step, we deliberately inoculated the collagen suspension with the different microorganisms tested. Then, 1 M NaOH was added to the suspension for 1 hour at 20 degrees C. We demonstrated that this treatment totally inactivated S. aureus, P. aeruginosa, C. albicans and A. niger which are bacterial strains responsible of severe human pathology. The reduction factors reached more than 4 logs for B. cereus spores and 4 logs for the porcine parvovirus. are encouraging as those two microorganisms are known to be very resistant to inactivation.


Assuntos
Bactérias/efeitos dos fármacos , Colágeno/isolamento & purificação , Contaminação de Medicamentos/prevenção & controle , Hidróxido de Sódio/farmacologia , Esterilização/métodos , Inativação de Vírus/efeitos dos fármacos , Vírus/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico/métodos , Desinfetantes/farmacologia , Suínos
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