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1.
J Acoust Soc Am ; 155(1): 206-217, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38180154

RESUMO

This article presents an improved and extended modeling approach for acoustic wave propagation in rigid porous materials, focusing on examples, such as plastic foams used for noise reduction in automotive applications. We demonstrate that the classical model (Johnson-Champoux-Allard) in the asymptotic high-frequency limit, widely employed in the literature, fails to accurately reconstruct the transmitted acoustic signal through high absorbent porous materials characterized by significant wave attenuation. The study focuses on the airborne ultrasonic frequency range (30-200 kHz). To address this limitation, we introduce new non-acoustic parameters Σ and V for viscous effects, and Σ' and V' for thermal effects, with surface and volumetric dimensions, respectively, allowing for the reconstruction of the transmitted signal and accurate modeling of the pronounced acoustic attenuation within the material. These parameters are incorporated into the expansion on skin depths of the dynamic tortuosity α(ω) and thermal tortuosity α' (ω) response functions, which describe the inertial-viscous and thermal interactions between the fluid and the solid, respectively. This novel modeling approach enables a more comprehensive study of high attenuating porous media, which are crucial for effective noise reduction. Additionally, it opens up new possibilities for characterization beyond the capabilities of current models.

2.
Ann Oncol ; 34(8): 703-713, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37269904

RESUMO

BACKGROUND: Mismatch repair-deficient (dMMR) tumors displaying microsatellite instability (MSI) represent a paradigm for the success of immune checkpoint inhibitor (ICI)-based immunotherapy, particularly in patients with metastatic colorectal cancer (mCRC). However, a proportion of patients with dMMR/MSI mCRC exhibit resistance to ICI. Identification of tools predicting MSI mCRC patient response to ICI is required for the design of future strategies further improving this therapy. PATIENTS AND METHODS: We combined high-throughput DNA and RNA sequencing of tumors from 116 patients with MSI mCRC treated with anti-programmed cell death protein 1 ± anti-cytotoxic T-lymphocyte-associated protein 4 of the NIPICOL phase II trial (C1, NCT03350126, discovery set) and the ImmunoMSI prospective cohort (C2, validation set). The DNA/RNA predictors whose status was significantly associated with ICI status of response in C1 were subsequently validated in C2. Primary endpoint was progression-free survival by immune RECIST (iRECIST) (iPFS). RESULTS: Analyses showed no impact of previously suggested DNA/RNA indicators of resistance to ICI, e.g. MSIsensor score, tumor mutational burden, or specific cellular and molecular tumoral contingents. By contrast, iPFS under ICI was shown in C1 and C2 to depend both on a multiplex MSI signature involving the mutations of 19 microsatellites hazard ratio cohort C2 (HRC2) = 3.63; 95% confidence interval (CI) 1.65-7.99; P = 1.4 × 10-3] and the expression of a set of 182 RNA markers with a non-epithelial transforming growth factor beta (TGFB)-related desmoplastic orientation (HRC2 = 1.75; 95% CI 1.03-2.98; P = 0.035). Both DNA and RNA signatures were independently predictive of iPFS. CONCLUSIONS: iPFS in patients with MSI mCRC can be predicted by simply analyzing the mutational status of DNA microsatellite-containing genes in epithelial tumor cells together with non-epithelial TGFB-related desmoplastic RNA markers.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Instabilidade de Microssatélites , Estudos Prospectivos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Reparo de Erro de Pareamento de DNA/genética
3.
Hum Reprod ; 38(4): 596-608, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36763673

RESUMO

STUDY QUESTION: Can artificial intelligence (AI) algorithms developed to assist embryologists in evaluating embryo morphokinetics be enriched with multi-centric clinical data to better predict clinical pregnancy outcome? SUMMARY ANSWER: Training algorithms on multi-centric clinical data significantly increased AUC compared to algorithms that only analyzed the time-lapse system (TLS) videos. WHAT IS KNOWN ALREADY: Several AI-based algorithms have been developed to predict pregnancy, most of them based only on analysis of the time-lapse recording of embryo development. It remains unclear, however, whether considering numerous clinical features can improve the predictive performances of time-lapse based embryo evaluation. STUDY DESIGN, SIZE, DURATION: A dataset of 9986 embryos (95.60% known clinical pregnancy outcome, 32.47% frozen transfers) from 5226 patients from 14 European fertility centers (in two countries) recorded with three different TLS was used to train and validate the algorithms. A total of 31 clinical factors were collected. A separate test set (447 videos) was used to compare performances between embryologists and the algorithm. PARTICIPANTS/MATERIALS, SETTING, METHODS: Clinical pregnancy (defined as a pregnancy leading to a fetal heartbeat) outcome was first predicted using a 3D convolutional neural network that analyzed videos of the embryonic development up to 2 or 3 days of development (33% of the database) or up to 5 or 6 days of development (67% of the database). The output video score was then fed as input alongside clinical features to a gradient boosting algorithm that generated a second score corresponding to the hybrid model. AUC was computed across 7-fold of the validation dataset for both models. These predictions were compared to those of 13 senior embryologists made on the test dataset. MAIN RESULTS AND THE ROLE OF CHANCE: The average AUC of the hybrid model across all 7-fold was significantly higher than that of the video model (0.727 versus 0.684, respectively, P = 0.015; Wilcoxon test). A SHapley Additive exPlanations (SHAP) analysis of the hybrid model showed that the six first most important features to predict pregnancy were morphokinetics of the embryo (video score), oocyte age, total gonadotrophin dose intake, number of embryos generated, number of oocytes retrieved, and endometrium thickness. The hybrid model was shown to be superior to embryologists with respect to different metrics, including the balanced accuracy (P ≤ 0.003; Wilcoxon test). The likelihood of pregnancy was linearly linked to the hybrid score, with increasing odds ratio (maximum P-value = 0.001), demonstrating the ranking capacity of the model. Training individual hybrid models did not improve predictive performance. A clinic hold-out experiment was conducted and resulted in AUCs ranging between 0.63 and 0.73. Performance of the hybrid model did not vary between TLS or between subgroups of embryos transferred at different days of embryonic development. The hybrid model did fare better for patients older than 35 years (P < 0.001; Mann-Whitney test), and for fresh transfers (P < 0.001; Mann-Whitney test). LIMITATIONS, REASONS FOR CAUTION: Participant centers were located in two countries, thus limiting the generalization of our conclusion to wider subpopulations of patients. Not all clinical features were available for all embryos, thus limiting the performances of the hybrid model in some instances. WIDER IMPLICATIONS OF THE FINDINGS: Our study suggests that considering clinical data improves pregnancy predictive performances and that there is no need to retrain algorithms at the clinic level unless they follow strikingly different practices. This study characterizes a versatile AI algorithm with similar performance on different time-lapse microscopes and on embryos transferred at different development stages. It can also help with patients of different ages and protocols used but with varying performances, presumably because the task of predicting fetal heartbeat becomes more or less hard depending on the clinical context. This AI model can be made widely available and can help embryologists in a wide range of clinical scenarios to standardize their practices. STUDY FUNDING/COMPETING INTEREST(S): Funding for the study was provided by ImVitro with grant funding received in part from BPIFrance (Bourse French Tech Emergence (DOS0106572/00), Paris Innovation Amorçage (DOS0132841/00), and Aide au Développement DeepTech (DOS0152872/00)). A.B.-C. is a co-owner of, and holds stocks in, ImVitro SAS. A.B.-C. and F.D.M. hold a patent for 'Devices and processes for machine learning prediction of in vitro fertilization' (EP20305914.2). A.D., N.D., M.M.F., and F.D.M. are or have been employees of ImVitro and have been granted stock options. X.P.-V. has been paid as a consultant to ImVitro and has been granted stocks options of ImVitro. L.C.-D. and C.G.-S. have undertaken paid consultancy for ImVitro SAS. The remaining authors have no conflicts to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Inteligência Artificial , Transferência Embrionária , Feminino , Gravidez , Humanos , Transferência Embrionária/métodos , Frequência Cardíaca Fetal , Imagem com Lapso de Tempo , Fertilização in vitro , Taxa de Gravidez
4.
Phys Rev Lett ; 127(17): 175002, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34739267

RESUMO

We report a laser-plasma experiment that was carried out at the LMJ-PETAL facility and realized the first magnetized, turbulent, supersonic (Ma_{turb}≈2.5) plasma with a large magnetic Reynolds number (Rm≈45) in the laboratory. Initial seed magnetic fields were amplified, but only moderately so, and did not become dynamically significant. A notable absence of magnetic energy at scales smaller than the outer scale of the turbulent cascade was also observed. Our results support the notion that moderately supersonic, low-magnetic-Prandtl-number plasma turbulence is inefficient at amplifying magnetic fields compared to its subsonic, incompressible counterpart.

5.
Ann Oncol ; 31(7): 921-929, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32294529

RESUMO

BACKGROUND: The Immunoscore (IS), which prognostically classifies stage I-III colon cancer (CC) patients, was evaluated in the International Duration Evaluation of Adjuvant Therapy (IDEA) France cohort study investigating 3 versus 6 months of oxaliplatin-based adjuvant chemotherapy in stage III CC patients. PATIENTS AND METHODS: Densities of CD3+ and CD8+ T cells in the tumor and invasive margin were determined by immunohistochemistry, quantified by digital pathology, and converted to IS. Mismatch repair status was determined by immunohistochemistry or by pentaplex PCR. Prediction of disease-free survival (DFS) by IS was analyzed by a multivariable Cox regression model in each study arm. Harrell's C-statistics were used to investigate the IS performance. RESULTS: Samples of 1322 patients were available. IS Low, Intermediate (Int), and High were observed in 43.6%, 47.0%, and 9.4% of patients, respectively. IS Low identified patients at higher risk of relapse or death compared with Int + High [hazard ratio (HR) = 1.54; 95% confidence interval (CI) 1.24-1.93, P = 0.0001]. The 3-year DFS was 66.80% (95% CI 62.23-70.94) for IS Low and 77.14% (95% CI 73.50-80.35) for IS Int + High. In multivariable analysis, IS remained significantly independently associated with DFS (P = 0.003) when adjusted for sex, histological grade, T/N stage, and microsatellite instability. For mFOLFOX6-treated patients (91.6% of the cohort), a statistical significant interaction was observed for the predictive value of IS for treatment duration (3 versus 6 months) in terms of DFS (P = 0.057). IS Int + High significantly predicted benefit of 6 months of treatment (HR = 0.53; 95% CI 0.37-0.75; P = 0.0004), including clinically low- and high-risk stage III CC (all P < 0.001). Conversely, patients with IS Low (46.4%) did not significantly benefit from the 6-month mFOLFOX6 versus the 3-month mFOLFOX6. CONCLUSIONS: The prognostic value of IS for DFS was confirmed in patients with stage III CC treated with oxaliplatin-based chemotherapy. Its predictive value for DFS benefit of longer duration of mFOLFOX6 adjuvant treatment was found in IS Int + High. These results will be validated in an external independent cohort. CLINICALTRIALS. GOV REGISTRATION: NCT03422601; EudraCT Number: 2009-010384-16.


Assuntos
Neoplasias do Colo , Duração da Terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Estudos de Coortes , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Fluoruracila/uso terapêutico , França , Humanos , Estadiamento de Neoplasias , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Prognóstico , Estudos Prospectivos
6.
Cereb Cortex ; 28(10): 3429-3444, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29194486

RESUMO

Characteristic preterm EEG patterns of "Delta-brushes" (DBs) have been reported in the temporal cortex following auditory stimuli, but their spatio-temporal dynamics remains elusive. Using 32-electrode EEG recordings and co-registration of electrodes' position to 3D-MRI of age-matched neonates, we explored the cortical auditory-evoked responses (AERs) after 'click' stimuli in 30 healthy neonates aged 30-38 post-menstrual weeks (PMW). (1) We visually identified auditory-evoked DBs within AERs in all the babies between 30 and 33 PMW and a decreasing response rate afterwards. (2) The AERs showed an increase in EEG power from delta to gamma frequency bands over the middle and posterior temporal regions with higher values in quiet sleep and on the right. (3) Time-frequency and averaging analyses showed that the delta component of DBs, which negatively peaked around 550 and 750 ms over the middle and posterior temporal regions, respectively, was superimposed with fast (alpha-gamma) oscillations and corresponded to the late part of the cortical auditory-evoked potential (CAEP), a feature missed when using classical CAEP processing. As evoked DBs rate and AERs delta to alpha frequency power decreased until full term, auditory-evoked DBs are thus associated with the prenatal development of auditory processing and may suggest an early emerging hemispheric specialization.


Assuntos
Audiometria de Resposta Evocada , Córtex Cerebral/fisiologia , Recém-Nascido Prematuro/fisiologia , Estimulação Acústica , Ritmo alfa/fisiologia , Ritmo Delta/fisiologia , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia , Feminino , Ritmo Gama , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Sono/fisiologia
7.
J Autoimmun ; 94: 99-109, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30061014

RESUMO

BACKGROUND: Mammalian target of rapamycin complex 1 (mTORC 1) drives the proinflammatory expansion of T helper (TH) type 1, TH17 cells and controls fibroblast proliferation, typical features of large vessel vasculitis (LVV) pathogenesis. Molecular pathways involved in arterial lesions of LVV are unknown. METHODS: We evaluate mTORC pathway activation in vascular aorta lesions and in T cell homeostasis of patients with LVV. RESULTS: Proliferation of both endothelial cells and vascular smooth-muscle cells was shown in vascular lesions in LVV. The vascular endothelium of proliferating aorta vessels from patients with LVV showed indications of activation of the mTORC1 pathway (S6RP phosphorylation). In cultured vascular endothelial cells, sera from patients with LVV stimulated mTORC1 through the phosphorylation of S6RP. mTORC1 activation was found also in Th1 and Th17 cells both systemically and in inflamed vessels. Patients with LVV exhibited a diminished S6RP phosphorylation in Tregs. Inhibition of mTORC1 pathway with rapamycin, increase Tregs and decrease effector CD4+IFNγ+, CD4+IL17+ and CD4+IL21+ T cells in patients with LVV. CONCLUSIONS: We provided evidence that mTORC1 pathway has a central role in driving T cell inflammation and vascular lesions in LVV. Targeting mTORC pathway may represent a new therapeutic option in patients with LVV.


Assuntos
Células Endoteliais/imunologia , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Miócitos de Músculo Liso/imunologia , Linfócitos T Reguladores/imunologia , Serina-Treonina Quinases TOR/genética , Vasculite/genética , Adulto , Idoso , Aorta/efeitos dos fármacos , Aorta/imunologia , Aorta/patologia , Estudos de Casos e Controles , Proliferação de Células , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucinas/genética , Interleucinas/imunologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 1 de Rapamicina/imunologia , Pessoa de Meia-Idade , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/patologia , Fosforilação/efeitos dos fármacos , Cultura Primária de Células , Transdução de Sinais , Sirolimo/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/patologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/imunologia , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/patologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th17/patologia , Vasculite/imunologia , Vasculite/patologia
8.
J Med Genet ; 52(11): 770-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26318770

RESUMO

BACKGROUND: Constitutional mismatch repair deficiency (CMMRD) syndrome is a childhood cancer predisposition syndrome involving biallelic germline mutations of MMR genes, poorly recognised by clinicians so far. METHODS: Retrospective review of all 31 patients with CMMRD diagnosed in French genetics laboratories in order to describe the characteristics, treatment and outcome of the malignancies and biological diagnostic data. RESULTS: 67 tumours were diagnosed in 31 patients, 25 (37%) Lynch syndrome-associated malignancies, 22 (33%) brain tumours, 17 (25%) haematological malignancies and 3 (5%) sarcomas. The median age of onset of the first tumour was 6.9 years (1.2-33.5). Overall, 22 patients died, 9 (41%) due to the primary tumour. Median survival after the diagnosis of the primary tumour was 27 months (0.26-213.2). Failure rate seemed to be higher than expected especially for T-cell non-Hodgkin's lymphoma (progression/relapse in 6/12 patients). A familial history of Lynch syndrome was identified in 6/23 families, and consanguinity in 9/23 families. PMS2 mutations (n=18) were more frequent than other mutations (MSH6 (n=6), MLH1 (n=4) and MSH2 (n=3)). CONCLUSIONS: In conclusion, this unselected series of patients confirms the extreme severity of this syndrome with a high mortality rate mostly related to multiple childhood cancers, and highlights the need for its early detection in order to adapt treatment and surveillance.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Colorretais/diagnóstico , Síndromes Neoplásicas Hereditárias/diagnóstico , Proteínas Adaptadoras de Transdução de Sinal/genética , Adenosina Trifosfatases/genética , Adolescente , Adulto , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Criança , Pré-Escolar , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Enzimas Reparadoras do DNA/genética , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Lactente , Masculino , Endonuclease PMS2 de Reparo de Erro de Pareamento , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS/genética , Mutação , Síndromes Neoplásicas Hereditárias/genética , Síndromes Neoplásicas Hereditárias/terapia , Proteínas Nucleares/genética , Resultado do Tratamento , Adulto Jovem
10.
J Med Genet ; 51(5): 283-93, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24556086

RESUMO

Lynch syndrome (LS) is an autosomal dominant disorder caused by a defect in one of the DNA mismatch repair genes: MLH1, MSH2, MSH6 and PMS2. In the last 15 years, an increasing number of patients have been described with biallelic mismatch repair gene mutations causing a syndrome referred to as 'constitutional mismatch repair-deficiency' (CMMR-D). The spectrum of cancers observed in this syndrome differs from that found in LS, as about half develop brain tumours, around half develop digestive tract cancers and a third develop haematological malignancies. Brain tumours and haematological malignancies are mainly diagnosed in the first decade of life, and colorectal cancer (CRC) and small bowel cancer in the second and third decades of life. Surveillance for CRC in patients with LS is very effective. Therefore, an important question is whether surveillance for the most common CMMR-D-associated cancers will also be effective. Recently, a new European consortium was established with the aim of improving care for patients with CMMR-D. At a workshop of this group held in Paris in June 2013, one of the issues addressed was the development of surveillance guidelines. In 1968, criteria were proposed by WHO that should be met prior to the implementation of screening programmes. These criteria were used to assess surveillance in CMMR-D. The evaluation showed that surveillance for CRC is the only part of the programme that largely complies with the WHO criteria. The values of all other suggested screening protocols are unknown. In particular, it is questionable whether surveillance for haematological malignancies improves the already favourable outcome for patients with these tumours. Based on the available knowledge and the discussions at the workshop, the European consortium proposed a surveillance protocol. Prospective collection of all results of the surveillance is needed to evaluate the effectiveness of the programme.


Assuntos
Neoplasias Encefálicas/diagnóstico , Distúrbios no Reparo do DNA/genética , Neoplasias do Sistema Digestório/diagnóstico , Neoplasias/diagnóstico , Neoplasias Encefálicas/etiologia , Neoplasias Colorretais/genética , Neoplasias Colorretais Hereditárias sem Polipose/tratamento farmacológico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Distúrbios no Reparo do DNA/complicações , Humanos , Leucemia/diagnóstico , Mutação , Neoplasias/etiologia , Vigilância da População
11.
J Hosp Infect ; 147: 47-55, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38467250

RESUMO

INTRODUCTION: Infection control measures are effective for nosocomial COVID-19 prevention but bear substantial health-economic costs, motivating their "de-escalation" in settings at low risk of SARS-CoV-2 transmission. Yet consequences of de-escalation are difficult to predict, particularly in light of novel variants and heterogeneous population immunity. AIM: To estimate how infection control measure de-escalation influences nosocomial COVID-19 risk. METHODS: An individual-based transmission model was used to simulate SARS-CoV-2 outbreaks and control measure de-escalation in a French long-term care hospital with multi-modal control measures in place (testing and isolation, universal masking, single-occupant rooms). Estimates of COVID-19 case fatality rates (CFRs) from reported outbreaks were used to quantify excess COVID-19 mortality due to de-escalation. RESULTS: In a population fully susceptible to infection, de-escalating both universal masking and single rooms resulted in hospital-wide outbreaks of 114 (95% CI: 103-125) excess infections, compared with five (three to seven) excess infections when de-escalating only universal masking or 15 (11-18) when de-escalating only single rooms. When de-escalating both measures and applying CFRs from the first wave of COVID-19, excess patient mortality ranged from 1.57 (1.41-1.71) to 9.66 (8.73-10.57) excess deaths/1000 patient-days. By contrast, when applying CFRs from subsequent pandemic waves and assuming susceptibility to infection among 40-60% of individuals, excess mortality ranged from 0 (0-0) to 0.92 (0.77-1.07) excess deaths/1000 patient-days. CONCLUSIONS: The de-escalation of bundled COVID-19 control measures may facilitate widespread nosocomial SARS-CoV-2 transmission. However, excess mortality is probably limited in populations at least moderately immune to infection and given CFRs resembling those estimated during the 'post-vaccine' era.


Assuntos
COVID-19 , Infecção Hospitalar , Controle de Infecções , SARS-CoV-2 , COVID-19/mortalidade , COVID-19/transmissão , COVID-19/prevenção & controle , COVID-19/epidemiologia , Humanos , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/transmissão , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/mortalidade , França/epidemiologia , Controle de Infecções/métodos , Idoso , Masculino , Máscaras/estatística & dados numéricos , Pessoa de Meia-Idade
12.
J Appl Microbiol ; 113(6): 1479-90, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22900936

RESUMO

AIMS: To establish protocols for the simultaneous detection and identification of Xanthomonas species causing tomato bacterial spot. METHODS AND RESULTS: We verified the specificity and sensitivity of the previously reported sets of primers designed for strains of the four species of Brazilian tomato bacterial spot xanthomonads, consisting of 30 of Xanthomonas euvesicatoria, 30 of X. vesicatoria, 50 of X. perforans and 50 of X. gardneri. Furthermore, we tested a multiplex PCR protocol for the purpose of concurrent species identification. The possibility of direct detection of the pathogens in diseased leaf samples was also verified. The primers were highly specific, amplifying only target DNA. The sensitivity of the primers in conventional PCR was 50 pg µl(-1) for purified DNA and ranged from 5 × 10(2) to 5 × 10(4) CFU ml(-1) when bacterial suspensions were analysed. The multiplex PCR was suitable for the detection of all four species and showed similar sensitivity to conventional PCR when tested on purified DNA. When using bacterial suspensions, its sensitivity was similar to conventional PCR only when a biological amplification step (Bio-PCR) was included. Both methods were able to detect the pathogens in symptomatic tomato leaves. CONCLUSIONS: Brazilian Xanthomonas strains causing tomato bacterial spot can be differentiated and identified at species level by a PCR-based method and by a multiplex PCR. SIGNIFICANCE AND IMPACT OF THE STUDY: This protocol may be a feasible alternative tool for the identification and detection of these pathogens in plant material and may be used for routine diagnostic purposes in plant pathology laboratories.


Assuntos
Reação em Cadeia da Polimerase Multiplex , Doenças das Plantas/microbiologia , Solanum lycopersicum/microbiologia , Xanthomonas/isolamento & purificação , Brasil , Primers do DNA/genética , DNA Bacteriano/isolamento & purificação , Folhas de Planta/microbiologia , Sensibilidade e Especificidade , Especificidade da Espécie , Xanthomonas/classificação , Xanthomonas/genética
13.
Osteoarthritis Cartilage ; 19(2): 194-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21056679

RESUMO

OBJECTIVES: (1) to investigate the test-retest reliability of 3D gait analysis (3DGA) in hip Osteoarthritis (OA) patients; (2) to find the minimum number of gait trials needed to overcome intrinsic variability; (3) to check the accuracy of angles measured by the 3D system. DESIGN: 23 Patients suffering from hip OA with no other major disease were recruited. We evaluated the reliability of spatio-temporal variables and body angles (lower-limb joints, trunk and pelvis angles) during two sessions of 3DGA using intra-class correlation coefficients (ICC). The minimum number of trials needed to overcome intrinsic variability was evaluated using an exponential fit model and the Bland and Altman coefficient of repeatability (CoR). The accuracy of measurement was evaluated using a manual goniometer and the recording of 18 different angles. RESULTS: Spatio-temporal variables and most of the kinematic joint and trunk angles calculated demonstrated good to excellent reliability (ICC from 0.77 to 0.97). This was not the case for pelvic angles. The fitting model combined with the CoR showed that 5-10 trials are sufficient to obtain good reliability [ICC>0.7; CoR<2 standard deviation (SD)] for most of the spatio-temporal variables. All body angles showed good reliability (ICC>0.7) and low CoR (<2 SD) after five trials except for the pelvic angles. The reliability of marker positioning was found to be good (ICC>0.7) to excellent (ICC>0.9). Differences between angles measured using 3DGA and angles measured with a manual goniometer were found to be less than one percent. CONCLUSION: The present study shows that most of variables obtained using 3DGA in hip OA patients are reliable. Moreover, for most variables, 5-10 trials are needed to obtain good reliability and to overcome intrinsic variability, rather than 30 or more, thus improving the feasibility of measurement.


Assuntos
Articulação do Tornozelo/fisiopatologia , Marcha/fisiologia , Articulação do Quadril/fisiopatologia , Articulação do Joelho/fisiopatologia , Osteoartrite do Quadril/fisiopatologia , Idoso , Fenômenos Biomecânicos , Feminino , Humanos , Imageamento Tridimensional/normas , Cinética , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
14.
Nanotechnology ; 22(16): 165301, 2011 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-21393822

RESUMO

In this paper, we describe wafer-scale fabrication and characterization of plasmonic chips-containing different sizes and spacings of metallic micro- and nanoline structures-using deep UV lithography. Using a high dose (25 mJ cm( - 2)) and a proper lift-off process, feature sizes as small as 25 nm are obtained. Moreover, we study the dependence of surface plasmon resonance on the angle of incidence and wavelength for different micro- and nanoline size and spacing values, yielding localized to quasi-propagative plasmonic behaviors. Rigorous coupled wave analysis (RCWA) techniques are employed to numerically confirm these experimental observations. Finally, the refractive index of media around the SPRI sensor chips is varied, showing the angulo-spectral regions of higher sensitivity for each type of structure.


Assuntos
Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Ressonância de Plasmônio de Superfície/métodos , Substâncias Macromoleculares/química , Substâncias Macromoleculares/efeitos da radiação , Teste de Materiais , Conformação Molecular/efeitos da radiação , Nanoestruturas/efeitos da radiação , Tamanho da Partícula , Doses de Radiação , Propriedades de Superfície/efeitos da radiação , Raios Ultravioleta
15.
ESMO Open ; 6(3): 100120, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33930657

RESUMO

BACKGROUND: DNA mismatch repair system deficiency (dMMR) is found in 15% of colorectal cancers (CRCs). Two methods are used to determine dMMR, immunohistochemistry (IHC) of MMR proteins and molecular testing of microsatellite instability (MSI). Only studies with a low number of patients have reported rates of discordance between these two methods, ranging from 1% to 10%. MATERIALS AND METHODS: Overall, 3228 consecutive patients with CRCs from two centers were included. Molecular testing was carried out using the Pentaplex panel and IHC evaluated four (MLH1, MSH2, MSH6, and PMS2; cohort 1; n = 1085) or two MMR proteins (MLH1 and MSH2; cohort 2; n = 2143). The primary endpoint was the rate of discordance between MSI and MMR IHC tests. RESULTS: Fifty-one discordant cases (1.6%) were initially observed. Twenty-nine out of 51 discordant cases were related to IHC misclassifications. In cohort 1, after re-reading IHC and/or carrying out new IHC, 16 discordant cases were reclassified as nondiscordant. In cohort 2, after the addition of MSH6/PMS2 IHC and re-examination, 13 were reclassified as nondiscordant. In addition, 10 misclassifications of molecular tests were identified. Finally, only 12 discordant cases (0.4%) remained: 5 were proficient MMR/MSI and 7 were dMMR/microsatellite stable. CONCLUSIONS: Our study confirmed the high degree of concordance between MSI and MMR IHC tests. Discordant cases must be reviewed, and if needed, tests must be repeated and analyzed by an expert team.


Assuntos
Neoplasias Colorretais , Instabilidade de Microssatélites , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Reparo de Erro de Pareamento de DNA/genética , Humanos , Imunoquímica , Técnicas de Diagnóstico Molecular
16.
Arthritis Rheumatol ; 73(7): 1233-1243, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33538119

RESUMO

OBJECTIVE: Our aim was to compare transcriptome and phenotype profiles of CD4+ T cells and CD19+ B cells in patients with Takayasu arteritis (TAK), patients with giant cell arteritis (GCA), and healthy donors. METHODS: Gene expression analyses, flow cytometry immunophenotyping, T cell receptor (TCR) gene sequencing, and functional assessments of cells from peripheral blood and arterial lesions from TAK patients, GCA patients, and healthy donors were performed. RESULTS: Among the most significantly dysregulated genes in CD4+ T cells of TAK patients compared to GCA patients (n = 720 genes) and in CD4+ T cells of TAK patients compared to healthy donors (n = 1,447 genes), we identified a follicular helper T (Tfh) cell signature, which included CXCR5, CCR6, and CCL20 genes, that was transcriptionally up-regulated in TAK patients. Phenotypically, there was an increase in CD4+CXCR5+CCR6+CXCR3- Tfh17 cells in TAK patients that was associated with a significant enrichment of CD19+ B cell activation. Functionally, Tfh cells helped B cells to proliferate, differentiate into memory cells, and secrete IgG antibodies. Maturation of B cells was inhibited by JAK inhibitors. Locally, in areas of arterial inflammation, we found a higher proportion of tertiary lymphoid structures comprised CD4+, CXCR5+, programmed death 1+, and CD20+ cells in TAK patients compared to GCA patients. CD4+CXCR5+ T cells in the aortas of TAK patients had an oligoclonal α/ß TCR repertoire. CONCLUSION: We established the presence of a specific Tfh cell signature in both circulating and aorta-infiltrating CD4+ T cells from TAK patients. The cooperation of Tfh cells and B cells might be critical in the occurrence of vascular inflammation in patients with TAK.


Assuntos
Linfócitos B/imunologia , Arterite de Células Gigantes/imunologia , Células T Auxiliares Foliculares/imunologia , Arterite de Takayasu/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD19/metabolismo , Antígenos CD20/metabolismo , Aorta , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Arterite de Células Gigantes/genética , Humanos , Imunoglobulina G/metabolismo , Memória Imunológica , Imunofenotipagem , Inibidores de Janus Quinases/farmacologia , Masculino , Pessoa de Meia-Idade , Nitrilas , Receptor de Morte Celular Programada 1/metabolismo , Pirazóis/farmacologia , Pirimidinas , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores CXCR5/metabolismo , Células T Auxiliares Foliculares/efeitos dos fármacos , Células T Auxiliares Foliculares/metabolismo , Arterite de Takayasu/genética , Estruturas Linfoides Terciárias/imunologia , Estruturas Linfoides Terciárias/metabolismo , Estruturas Linfoides Terciárias/patologia , Transcriptoma
17.
Br J Cancer ; 103(12): 1840-5, 2010 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21081928

RESUMO

BACKGROUND: microsatellite instability (MSI) is commonly screened using a panel of two mononucleotide and three dinucleotide repeats as recommended by a consensus meeting on MSI tumours held at the National Cancer Institute (Bethesda, MD, USA). According to these recommendations, tumours are classified as MSI-H when at least two of the five microsatellite markers show instability, MSI-L when only one marker shows instability and MSS when none of the markers show instability. Almost all MSI-H tumours are characterised by alterations in one of the four major proteins of the mismatch repair (MMR) system (MLH1, MSH2, MSH6 or PMS2) that renders them MMR deficient, whereas MSI-L and MSS tumours are generally MMR proficient. However, tumours from patients with a pathogenic germline mutation in MSH6 can sometimes present an MSI-L phenotype with the NCI panel. The MSH6 protein is not involved in the repair of mismatches of two nucleotides in length and consequently the three dinucleotide repeats of the NCI panel often show stability in MSH6-deficient tumours. METHODS: a pentaplex panel comprising five mononucleotide repeats has been recommended as an alternative to the NCI panel to determine tumour MSI status. Several studies have confirmed the sensitivity, specificity and ease of use of the pentaplex panel; however, its sensitivity for the detection of MSH6-deficient tumours is so far unknown. Here, we used the pentaplex panel to evaluate MSI status in 29 tumours known to harbour an MSH6 defect. RESULTS: MSI-H status was confirmed in 15 out of 15 (100%) cases where matching normal DNA was available and in 28 out of 29 (97%) cases where matching DNA was not available or was not analysed. CONCLUSION: these results show that the pentaplex assay efficiently discriminates the MSI status of tumours with an MSH6 defect.


Assuntos
Proteínas de Ligação a DNA/genética , Instabilidade de Microssatélites , Neoplasias/genética , Sequências Repetitivas de Ácido Nucleico , Reparo de Erro de Pareamento de DNA , Humanos , Reação em Cadeia da Polimerase
18.
Ann Oncol ; 21(4): 772-780, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19833818

RESUMO

BACKGROUND: The aim was to determine the values of p53 tumour expression and microsatellite instability (MSI) phenotype to predict benefit from adjuvant chemotherapy of colon cancer by 5-fluorouracil and leucovorin (FL) alone or with oxaliplatin (FOLFOX). PATIENTS AND METHODS: This retrospective study included 233 unselected patients with stage III colon cancer treated by FL (n = 124) or FOLFOX (n = 109). The impact of p53 expression and MSI on disease-free survival (DFS) was defined using univariate and multivariate analyses. A Cox proportional hazards model was specifically designed to evaluate the interaction between chemotherapy and these genetic alterations. RESULTS: In univariate analyses, addition of oxaliplatin significantly improved DFS provided that tumour overexpressed p53 [hazard ratio (HR) 0.39; 95% confidence interval (CI) 0.19-0.82; P = 0.01] or displayed MSI phenotype (HR 0.17; 95% CI 0.04-0.68; P = 0.01). In multivariate analyses, p53 was confirmed as an independent factor predictive of benefit from FOLFOX (P = 0.03), while the interaction of MSI with chemotherapy could not be determined in the absence of relapse in the MSI group treated with FOLFOX. CONCLUSION: Our observations indicate that MSI status and p53 expression may influence the impact of oxaliplatin on adjuvant treatment of stage III colon cancer patients.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Instabilidade de Microssatélites , Proteína Supressora de Tumor p53/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Estudos Retrospectivos , Proteína Supressora de Tumor p53/fisiologia
19.
Clin Exp Rheumatol ; 28(6): 806-12, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21205459

RESUMO

OBJECTIVES: The Rheumatoid and Arthritis Outcome Score (RAOS) was recently developed to evaluate functional disability and quality of life in rheumatoid arthritis (RA) patients suffering from lower limb symptoms. The aims of this study were to cross-culturally adapt the RAOS into French and to assess its psychometric properties, in particular, responsiveness following intra-articular therapy. METHODS: The French RAOS was developed according to cross-cultural guidelines and was then evaluated in symptomatic RA patients with lower limb joint involvement. The psychometric properties assessed were - feasibility: percentage of missing data and floor and ceiling effects; reliability: intra-class correlation coefficients (ICC, and Bland and Altman representation; internal consistency: Cronbach's alpha; construct validity by correlation with the SF-36 and HAQ (Spearman's rank test); responsiveness to intra-articular corticosteroid injection (hip, knee, hindfoot) using standardised response mean (SRM) and effect size. RESULTS: Sixty patients were included (mean age 50.1±10.5 years). Neither floor nor ceiling effects were observed. Reliability was good with ICC for different RAOS subscales ranging from 0.76 to 0.91. Results for internal consistency (Cronbach's alpha ranging from 0.73 to 0.91) and construct validity were good. The responsiveness was moderate to large with SRMs ranging from 0.75 to 0.87 and effect sizes from 0.77 to 1.75 at two weeks following intra-articular corticosteroid injection. CONCLUSIONS: The French version of the RAOS demonstrated good psychometric properties to capture functional disability and quality of life in RA. Moreover, the results suggest that the RAOS could be used as an outcome in trials evaluating single joint intra-articular injections.


Assuntos
Artrite Reumatoide , Cultura , Avaliação da Deficiência , Idioma , Qualidade de Vida , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Adulto , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/fisiopatologia , Artrite Reumatoide/psicologia , Feminino , França , Humanos , Injeções Intra-Articulares , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Psicometria , Reprodutibilidade dos Testes , Resultado do Tratamento
20.
Ann Dermatol Venereol ; 137(1): 36-9, 2010 Jan.
Artigo em Francês | MEDLINE | ID: mdl-20110066

RESUMO

BACKGROUND: Voriconazole is a systemic antifungal drug that can induce phototoxic reactions suggestive of porphyria cutanea tarda (PCT); however, porphyrin levels in urine, blood and stool remain within the normal range. Superficial cheilitis is frequently associated with this clinical picture; it is believed to be related to drug-induced impairment of endogenous retinoid metabolism. We report a case of true PCT associated with cheilitis, both occurring soon after the introduction of voriconazole and partially disappearing after withdrawal of this drug. CASE REPORT: A 65-year-old man with a past history of excessive alcohol consumption presented with typical features of PCT associated with a mild superficial desquamating cheilitis. Both symptoms had appeared 12 days after initiation of oral voriconazole for a cavitary aspergillosis. Laboratory tests confirmed a sporadic case of PCT. Withdrawal of voriconazole (replaced by itraconazole) resulted in complete disappearance of the cheilitis but incomplete remission of the PCT. Ultimately, the patient was successfully treated by venous puncture. DISCUSSION: This patient had both voriconazole-induced superficial cheilitis and a true PCT which seemed related to the same drug. The mechanism by which voriconazole may have revealed PCT remains elusive and could possibly have involved decreased uroporphyrinogen decarboxylase activity in the liver or potentiation of the phototoxic effects of porphyrins by the cutaneous toxicity of voriconazole. CONCLUSION: On presentation of a clinical picture of PCT-like photosensitivity in a patient on voriconazole, laboratory investigations should be performed routinely to rule out true PCT, even in cases of associated cheilitis.


Assuntos
Antifúngicos/efeitos adversos , Transtornos de Fotossensibilidade/induzido quimicamente , Porfiria Cutânea Tardia/diagnóstico , Pirimidinas/efeitos adversos , Triazóis/efeitos adversos , Idoso , Alcoolismo/complicações , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Queilite/induzido quimicamente , Fezes/química , Humanos , Fígado/enzimologia , Masculino , Porfiria Cutânea Tardia/complicações , Porfirinas/análise , Porfirinas/sangue , Porfirinas/urina , Aspergilose Pulmonar/complicações , Aspergilose Pulmonar/tratamento farmacológico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Triazóis/farmacologia , Triazóis/uso terapêutico , Uroporfirinogênio Descarboxilase/antagonistas & inibidores , Voriconazol
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