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1.
Infect Dis Now ; 53(6): 104727, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37268040

RESUMO

OBJECTIVES: Following various changes in the vaccine strategy in 2013 and the mandatory vaccination in 2018, we aimed to analyze the vaccination status, age, and source of contamination of pertussis and parapertussis cases in outpatient surveillance. PATIENTS AND METHODS: Confirmed pertussis and parapertussis cases were enrolled by 35 pediatricians. RESULTS: From 2014 to 2022, 73 confirmed cases of pertussis (n = 65) and parapertussis (n = 8) were reported. For children below 6 years of age, the number of cases with a 2 + 1 schedule (n = 22) was higher than that of those with a 3 + 1 schedule (n = 7). The age of cases with a 3 + 1 or a 2 + 1 schedule was not significantly different (3.8y ± 1.4 vs 4.2y ± 1.5). The main source of contamination was either adults or adolescents. CONCLUSION: Vaccination status and source of contamination are crucial to study the impact of vaccination recommendations.


Assuntos
Coqueluche , Adulto , Adolescente , Criança , Humanos , Coqueluche/epidemiologia , Coqueluche/prevenção & controle , Vacina contra Coqueluche , Incidência , Vacinação , França/epidemiologia
2.
Nat Commun ; 13(1): 6230, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266342

RESUMO

TET (Ten-Eleven Translocation) dioxygenases effect DNA demethylation through successive oxidation of the methyl group of 5-methylcytosine (5mC) in DNA. In humans and in mouse models, TET loss-of-function has been linked to DNA damage, genome instability and oncogenesis. Here we show that acute deletion of all three Tet genes, after brief exposure of triple-floxed, Cre-ERT2-expressing mouse embryonic stem cells (mESC) to 4-hydroxytamoxifen, results in chromosome mis-segregation and aneuploidy; moreover, embryos lacking all three TET proteins showed striking variation in blastomere numbers and nuclear morphology at the 8-cell stage. Transcriptional profiling revealed that mRNA encoding a KH-domain protein, Khdc3 (Filia), was downregulated in triple TET-deficient mESC, concomitantly with increased methylation of CpG dinucleotides in the vicinity of the Khdc3 gene. Restoring KHDC3 levels in triple Tet-deficient mESC prevented aneuploidy. Thus, TET proteins regulate Khdc3 gene expression, and TET deficiency results in mitotic infidelity and genome instability in mESC at least partly through decreased expression of KHDC3.


Assuntos
Aneuploidia , Proteínas de Ligação a DNA , Dioxigenases , Células-Tronco Embrionárias Murinas , Animais , Camundongos , 5-Metilcitosina/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , DNA/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Instabilidade Genômica , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , RNA Mensageiro/metabolismo
3.
Genome Biol ; 22(1): 186, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34158086

RESUMO

BACKGROUND: TET enzymes mediate DNA demethylation by oxidizing 5-methylcytosine (5mC) in DNA to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC). Since these oxidized methylcytosines (oxi-mCs) are not recognized by the maintenance methyltransferase DNMT1, DNA demethylation can occur through "passive," replication-dependent dilution when cells divide. A distinct, replication-independent ("active") mechanism of DNA demethylation involves excision of 5fC and 5caC by the DNA repair enzyme thymine DNA glycosylase (TDG), followed by base excision repair. RESULTS: Here by analyzing inducible gene-disrupted mice, we show that DNA demethylation during primary T cell differentiation occurs mainly through passive replication-dependent dilution of all three oxi-mCs, with only a negligible contribution from TDG. In addition, by pyridine borane sequencing (PB-seq), a simple recently developed method that directly maps 5fC/5caC at single-base resolution, we detect the accumulation of 5fC/5caC in TDG-deleted T cells. We also quantify the occurrence of concordant demethylation within and near enhancer regions in the Il4 locus. In an independent system that does not involve cell division, macrophages treated with liposaccharide accumulate 5hmC at enhancers and show altered gene expression without DNA demethylation; loss of TET enzymes disrupts gene expression, but loss of TDG has no effect. We also observe that mice with long-term (1 year) deletion of Tdg are healthy and show normal survival and hematopoiesis. CONCLUSIONS: We have quantified the relative contributions of TET and TDG to cell differentiation and DNA demethylation at representative loci in proliferating T cells. We find that TET enzymes regulate T cell differentiation and DNA demethylation primarily through passive dilution of oxi-mCs. In contrast, while we observe a low level of active, replication-independent DNA demethylation mediated by TDG, this process does not appear to be essential for immune cell activation or differentiation.


Assuntos
Metilação de DNA , Proteínas de Ligação a DNA/genética , Dioxigenases/genética , Macrófagos/enzimologia , Linfócitos T/enzimologia , Timina DNA Glicosilase/genética , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Citosina/análogos & derivados , Citosina/metabolismo , DNA/genética , DNA/metabolismo , Proteínas de Ligação a DNA/deficiência , Dioxigenases/deficiência , Elementos Facilitadores Genéticos , Expressão Gênica , Loci Gênicos , Hematopoese/genética , Interleucina-4/genética , Interleucina-4/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Lipopolissacarídeos/farmacologia , Longevidade/genética , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Knockout , Linfócitos T/citologia , Linfócitos T/imunologia , Timina DNA Glicosilase/deficiência
4.
Proc Natl Acad Sci U S A ; 116(25): 12410-12415, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31152140

RESUMO

T cells expressing chimeric antigen receptors (CAR T cells) have shown impressive therapeutic efficacy against leukemias and lymphomas. However, they have not been as effective against solid tumors because they become hyporesponsive ("exhausted" or "dysfunctional") within the tumor microenvironment, with decreased cytokine production and increased expression of several inhibitory surface receptors. Here we define a transcriptional network that mediates CD8+ T cell exhaustion. We show that the high-mobility group (HMG)-box transcription factors TOX and TOX2, as well as members of the NR4A family of nuclear receptors, are targets of the calcium/calcineurin-regulated transcription factor NFAT, even in the absence of its partner AP-1 (FOS-JUN). Using a previously established CAR T cell model, we show that TOX and TOX2 are highly induced in CD8+ CAR+ PD-1high TIM3high ("exhausted") tumor-infiltrating lymphocytes (CAR TILs), and CAR TILs deficient in both TOX and TOX2 (Tox DKO) are more effective than wild-type (WT), TOX-deficient, or TOX2-deficient CAR TILs in suppressing tumor growth and prolonging survival of tumor-bearing mice. Like NR4A-deficient CAR TILs, Tox DKO CAR TILs show increased cytokine expression, decreased expression of inhibitory receptors, and increased accessibility of regions enriched for motifs that bind activation-associated nuclear factor κB (NFκB) and basic region-leucine zipper (bZIP) transcription factors. These data indicate that Tox and Nr4a transcription factors are critical for the transcriptional program of CD8+ T cell exhaustion downstream of NFAT. We provide evidence for positive regulation of NR4A by TOX and of TOX by NR4A, and suggest that disruption of TOX and NR4A expression or activity could be promising strategies for cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Depleção Linfocítica , Fatores de Transcrição/metabolismo , Animais , Imunoterapia , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/terapia , Ligação Proteica , RNA Mensageiro/genética , Fatores de Transcrição/genética , Microambiente Tumoral
5.
J Hosp Infect ; 102(3): 297-303, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30771369

RESUMO

BACKGROUND: Meticillin-susceptible and -resistant Staphylococcus aureus (MSSA and MRSA) are responsible for outbreaks in intensive care units. MSSA infections have the same morbidity and mortality rate as MRSA infections but are studied less often. Whole-genome sequencing (WGS) is used increasingly for outbreak monitoring, but still requires specific installation and trained personnel to obtain and analyse the data. AIM: To evaluate the workflow and benefits of EpiSeq solution (bioMérieux, Marcy l'Etoile, France) in exploring the increased incidence of S. aureus bloodstream infections in a neonatal intensive care unit (NICU). METHODS: Four S. aureus bacteraemia isolates and 27 colonization isolates obtained between January and July 2016 were submitted to the 'all in one solution' EpiSeq [WGS, quality data assessment, multi-locus sequence typing (MLST), spa typing, virulome and resistome characterization, and phylogenetic tree construction]. More in-depth analyses were performed (whole-genome MLST and whole-genome single nucleotide polymorphism (wgSNP)] with BioNumerics software (Applied Maths, Sint-Martens-Latem, Belgium). FINDINGS: Nine different sequence types and 13 different spa types were found among the 31 isolates studied. Among those isolates, 11 (seven patients) were ST146 spa type t002, five (four patients) were ST30 and four (four patients) were ST398. The 11 ST146 isolates had a maximum of seven pairwise SNP differences. CONCLUSION: Use of EpiSeq solution allowed fast demonstration of the polyclonal profile of the MSSA population in neonates, and enabled the suspicion of a global outbreak to be ruled out. However, wgSNP analysis showed the transmission and persistence of one sequence type for over six months in the NICU, and enabled the infection control team to adapt its response.


Assuntos
Surtos de Doenças , Tipagem Molecular , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação , Sequenciamento Completo do Genoma , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Transmissão de Doença Infecciosa , França/epidemiologia , Variação Genética , Genótipo , Humanos , Incidência , Lactente , Unidades de Terapia Intensiva Neonatal , Epidemiologia Molecular , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética
7.
Arch Pediatr ; 24(12S): S9-S16, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29290238

RESUMO

ENT infections are the most common childhood infections and the leading causes of antibiotic prescriptions. These infections are mainly due to viruses and most of them (even if bacterial species are implicated) resolve spontaneously. Therefore, the first message is to not prescribe antibiotics in the following situations: common cold, non-streptococcal pharyngitis, laryngitis, non-purulent otitis media, etc. For sore throat/pharyngitis, the antibiotic treatment decision is based mainly on the use of group A streptococcus rapid diagnostic tests. For otitis media, only purulent forms occurring in children less than 2 years of age and most severe situations in older children should be treated with antibiotics. Amoxicillin is the first-line treatment for the vast majority of ENT infections requiring antibiotic treatment. Severe ENT infections (mastoiditis, epiglottitis, retro- and parapharyngeal abscesses, and ethmoiditis) are therapeutic emergencies requiring in most cases hospitalization and intravenous antibiotics.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Otorrinolaringopatias/tratamento farmacológico , Otorrinolaringopatias/microbiologia , Criança , Humanos , Guias de Prática Clínica como Assunto
8.
Arch Pediatr ; 24 Suppl 3: S24-S28, 2017 Dec.
Artigo em Francês | MEDLINE | ID: mdl-29433694

RESUMO

All newborns superior to 34 weeks of gestationnal age (GA) are concerned by these guidelines of the French Society of Neonatology and the French Society of Pediatrics. Only newborns at risk of Early-Onset Neonatal Bacterial Infection who are clinically symptomatic have to be treated with probabilistic antibiotherapy treatment. The antibiotic combination of choice is amoxicillin + gentamicin. The two exceptions that justify dual therapy with Cefotaxime and Gentamicin are the bacteriological documentation of Escherichia coli and/or the presence of clinical signs of severity. The continuation or not of the antibiotic treatment relies on the reevaluation of the clinical examination, the bacteriological culture results (blood culture and eventual Cerebro-Spinal-Fluid (CSF) culture) after 36-48 hours of treatment. Antibiotic treatment is continued for 7 days in case of positive blood culture, with amoxicillin alone if then bacterial species implicated are group B Streptococcus (GBS) or Listeria monocytogenes, with Cefotaxime alone in case of E.coli even if the strains are susceptible to aminopenicillins. In case of meningitis due to GBS or L. monocytogenes antibiotherapy is continued for 14 days with amoxicillin alone and 21 days of cefotaxime alone in case of E. coli meningitis. Specialist advice should be sought for other bacteria or extended-spectrum beat-lactamase-producing E. coli. and the absence of bacteriological documentation, according to the clinical evolution and the inflammatory parameters, it can be decided to continue or not the antibiotherapy.

12.
13.
J Biol Chem ; 290(11): 6844-56, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25623069

RESUMO

TBX5 is the gene mutated in Holt-Oram syndrome, an autosomal dominant disorder with complex heart and limb deformities. Its protein product is a member of the T-box family of transcription factors and an evolutionarily conserved dosage-sensitive regulator of heart and limb development. Understanding TBX5 regulation is therefore of paramount importance. Here we uncover the existence of novel exons and provide evidence that TBX5 activity may be extensively regulated through alternative splicing to produce protein isoforms with differing N- and C-terminal domains. These isoforms are also present in human heart, indicative of an evolutionarily conserved regulatory mechanism. The newly identified isoforms have different transcriptional properties and can antagonize TBX5a target gene activation. Droplet Digital PCR as well as immunohistochemistry with isoform-specific antibodies reveal differential as well as overlapping expression domains. In particular, we find that the predominant isoform in skeletal myoblasts is Tbx5c, and we show that it is dramatically up-regulated in differentiating myotubes and is essential for myotube formation. Mechanistically, TBX5c antagonizes TBX5a activation of pro-proliferative signals such as IGF-1, FGF-10, and BMP4. The results provide new insight into Tbx5 regulation and function that will further our understanding of its role in health and disease. The finding of new exons in the Tbx5 locus may also be relevant to mutational screening especially in the 30% of Holt-Oram syndrome patients with no mutations in the known TBX5a exons.


Assuntos
Éxons , Proteínas com Domínio T/análise , Proteínas com Domínio T/genética , Anormalidades Múltiplas/genética , Processamento Alternativo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Expressão Gênica , Cardiopatias Congênitas/genética , Comunicação Interatrial/genética , Humanos , Deformidades Congênitas das Extremidades Inferiores/genética , Camundongos , Dados de Sequência Molecular , Células Musculares/citologia , Células Musculares/metabolismo , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Mutação , Miocárdio/metabolismo , Miocárdio/ultraestrutura , Isoformas de Proteínas/análise , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Alinhamento de Sequência , Proteínas com Domínio T/metabolismo , Deformidades Congênitas das Extremidades Superiores/genética
14.
Arch Pediatr ; 21 Suppl 2: S97-S100, 2014 Nov.
Artigo em Francês | MEDLINE | ID: mdl-25456689

RESUMO

Perineal diseases in children are usually caused by group A streptococcus (GAS). If the natural course of untreated cases is not known, it is well known that symptoms do not resolve spontaneously and can persist often for many months, until appropriate diagnosis and effective treatment are instituted. Furthermore, failures and recurrences after penicillin treatment are frequent. From 2009 to 2014, 165 perineal infections (median age: 48 months, extremes: 0.4-139) were enrolled by 15 pediatricians: 4 balanitis, 29 vulvo-vaginal diseases and 132 perianal infections. Painful defecation, anal fissures and macroscopic blood in stools were significantly more frequent in GAS perianal infections than negative GAS infections (p<0.01). The performance of GAS-rapid antigen test compared to the GAS culture was : sensitivity 97 % [CI 95 %: 89-100 %], specificity 76 % [CI 95 %: 66-84 %], negative predictive value 97 % [CI 95 %: 91-100 %], positive predictive value 71 % [CI 95 %: 60-80 %].


Assuntos
Doenças do Ânus/diagnóstico , Doenças do Pênis/diagnóstico , Dermatopatias Bacterianas/diagnóstico , Infecções Estreptocócicas/diagnóstico , Streptococcus pyogenes , Doenças Vaginais/diagnóstico , Doenças da Vulva/diagnóstico , Antígenos de Bactérias/análise , Doenças do Ânus/microbiologia , Criança , Pré-Escolar , Feminino , França , Humanos , Testes Imunológicos , Lactente , Masculino , Doenças do Pênis/microbiologia , Dermatopatias Bacterianas/microbiologia , Infecções Estreptocócicas/tratamento farmacológico , Streptococcus pyogenes/imunologia , Doenças Vaginais/microbiologia , Doenças da Vulva/microbiologia
15.
Arch Pediatr ; 21(9): 1062-70, 2014 Sep.
Artigo em Francês | MEDLINE | ID: mdl-25153808

RESUMO

The French 2013 immunization schedule having a goal of simplification with comparable efficacy, has decreased the number of injections and removed the injection performed at three months of age in the general population. Apart from the prevention of invasive pneumococcal infections for which it is recommended to maintain three dose primary immunization, vaccination of premature is not addressed in this new calendar. Can the extremely preterm infants (<33 weeks of gestational age) benefit from this new schedule or should we keep them in three injections schedule? The objective of this paper is to clarify this point through the data available in the literature. Children born prematurely and especially the "extremely premature" born before 33 weeks are at high risk of infections, some of them are preventable by immunization. Although there is no clinical evidence, for pertussis, pneumococcus, Haemophilus influenzae b, hepatitis B, whatever the immunogenicity criteria, immunogenicity is significantly lower in preterm than in term newborn after 3 doses primary schedule. This lower immunogenicity raises concerns about the transition to two doses, about the ability to give short term protection and booster responses. Given these data, GPIP takes the position for maintaining a primary 3-dose vaccination at 2.3 and 4 months for premature infants less than 33 weeks.


Assuntos
Suscetibilidade a Doenças , Esquemas de Imunização , Recém-Nascido Prematuro , Vacinas Bacterianas/administração & dosagem , França , Humanos , Recém-Nascido , Vacinas Virais/administração & dosagem
16.
Int J Biomed Imaging ; 2014: 428583, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25587264

RESUMO

Visualization of the entire length of the gastrointestinal tract through natural orifices is a challenge for endoscopists. Videoendoscopy is currently the "gold standard" technique for diagnosis of different pathologies of the intestinal tract. Wireless capsule endoscopy (WCE) has been developed in the 1990s as an alternative to videoendoscopy to allow direct examination of the gastrointestinal tract without any need for sedation. Nevertheless, the systematic postexamination by the specialist of the 50,000 (for the small bowel) to 150,000 images (for the colon) of a complete acquisition using WCE remains time-consuming and challenging due to the poor quality of WCE images. In this paper, a semiautomatic segmentation for analysis of WCE images is proposed. Based on active contour segmentation, the proposed method introduces alpha-divergences, a flexible statistical similarity measure that gives a real flexibility to different types of gastrointestinal pathologies. Results of segmentation using the proposed approach are shown on different types of real-case examinations, from (multi)polyp(s) segmentation, to radiation enteritis delineation.

17.
Artigo em Inglês | MEDLINE | ID: mdl-24111034

RESUMO

This paper presents a new embeddable method for polyp detections in Wireless Capsule Endoscopic - WCE images. this approach consists first of extracting candidate polyps within the image using geometric considerations about related shape, and second, in classifying (polyp/non-polyp) obtained candidates by a boosting-based method using texture features. The proposed approach has been designed in accordance with the hardware constraints related to FPGA implementation for integration within WCE imaging device. The classification performance of the method have been evaluated on a large dataset of 300 polyps, and 1200 non-polyps images. Experiments show interesting and promising performance: the boosting-based classification is characterized by a sensitivity of 91%, a specificity of 95% and a false detection rate of 4.8%, the detection rate of the overall processing chain being of 68%. The performance of the boosting-based classification are in accordance with the most recent reference on this particular topic using the same dataset. Building of a dedicated WCE image database should permit the improvement of the global detection rate.


Assuntos
Algoritmos , Endoscopia por Cápsula/métodos , Sistemas Computacionais , Pólipos/diagnóstico , Bases de Dados como Assunto , Humanos , Processamento de Imagem Assistida por Computador , Sensibilidade e Especificidade
20.
J Hosp Infect ; 83(4): 333-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23414707

RESUMO

In neonatal intensive care units, topical agents represent an increasing part of the infection control armamentarium. Fifty-one coagulase-negative staphylococci (CNS) isolated from catheter-associated bloodstream infections in very preterm neonates were investigated in this study: 41.2% exhibited decreased susceptibility to at least one antiseptic (chlorhexidine 12%, benzalkonium 24%, acriflavine 33%) and 61% were resistant to mupirocin. QacA/B, mupA and both genes were detected by polymerase chain reaction in 59%, 63% and 49% of CNS, respectively. Seventy-six percent of Staphylococcus epidermidis (5/5 pulsed-field-gel electrophoresis subgroups) and 11% of Staphylococcus capitis (1/3 subgroups) were multi-resistant. Skin antisepsis using low-concentration aqueous formulations and off-label mupirocin indications should benefit from a stewardship programme.


Assuntos
Antibacterianos/farmacologia , Anti-Infecciosos Locais/farmacologia , Farmacorresistência Bacteriana , Lactente Extremamente Prematuro , Mupirocina/farmacologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus/efeitos dos fármacos , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/microbiologia , DNA Bacteriano/genética , Feminino , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Reação em Cadeia da Polimerase , Infecções Estafilocócicas/microbiologia , Staphylococcus/genética , Staphylococcus/isolamento & purificação
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