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1.
Sci Total Environ ; 880: 163338, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37023828

RESUMO

The accurate prediction of water dynamics is critical for operational water resource management. In this study, we propose a novel approach to perform long-term forecasts of daily water dynamics, including river levels, river discharges, and groundwater levels, with a lead time of 7-30 days. The approach is based on the state-of-the-art neural network, bidirectional long short-term memory (BiLSTM), to enhance the accuracy and consistency of dynamic predictions. The operation of this forecasting system relies on an in-situ database observed for over 50 years with records gauging in 19 rivers, the karst aquifer, the English Channel, and the meteorological network in Normandy, France. To address the problem of missing measurements and gauge installations over time, we developed an adaptive scheme in which the neural network is regularly adjusted and re-trained in response to changing inputs during a long operation. Advances in BiLSTM with extensive learning past-to-future and future-to-past further help to avoid time-lag calibration that simplifies data processing. The proposed approach provides high accuracy and consistent prediction for the three water dynamics within a similar accuracy range as an on-site observation, with approximately 3 % error in the measurement range for the 7 day-ahead predictions and 6 % error for the 30 d-ahead predictions. The system also effectively fills the gap in actual measurements and detects anomalies at gauges that can last for years. Working with multiple dynamics not only proves that the data-driven model is a unified approach but also reveals the impact of the physical background of the dynamics on the performance of their predictions. Groundwater undergoes a slow filtration process following a low-frequency fluctuation, favoring long-term prediction, which differs from other higher-frequency river dynamics. The physical nature drives the predictive performance even when using a data-driven model.

2.
Phys Chem Chem Phys ; 25(16): 11085-11092, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-36484473

RESUMO

Understanding the mechanisms of X-ray radiation damage in biological systems is of prime interest in medicine (radioprotection, X-ray therapy…). Study of low-energy rays, such as soft-X rays and light ions, points to attribute their lethal effect to clusters of energy deposition by low-energy electrons. The first step, at the atomic or molecular level, is often the ionization of inner-shell electrons followed by Auger decay in an aqueous environment. We have developed an experimental set-up to perform electron coincidence spectroscopy on molecules in a water micro-jet. We present here the first results obtained on sodium benzoate solutions, irradiated at the oxygen and carbon K-edges.

3.
Mil Med ; 188(1-2): e80-e85, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34114042

RESUMO

INTRODUCTION: The recent COVID-19 pandemic has underscored the necessity of protecting health care providers (HCPs) against the transmission of infectious agents during dental procedures. To this end, the effectiveness of several air cleaning devices (ACDs) in reducing HCPs exposure to aerosols generated during dental procedures was estimated, separately or in combination with each other. These ACDs were a chairside unit capturing aerosols at the source of generation, and four ambient ACDs: a portable ambient ACD; a negative pressure module; a custom made, fan-operated and wall-mounted air filter (WMAF); and a smaller and passive version of the latter. The last three ACDs were intended for mobile dental clinics (MDCs) only. MATERIALS AND METHODS: This assessment was performed in two different environments: in a dental clinic operatory and in a MDC. Two dental personnel, acting in the roles of dentist and dental assistant, performed on simulated patient aerosol-generating and non-aerosol-generating procedures. For each 5-minute scenario, the cumulative exposure to airborne particulate matter 10 µm in size or smaller (PM10) was determined by calculating the sum of all 1 second readings obtained with personal and ambient air monitors. The effectiveness of the ACDs in capturing PM10 was estimated based on the capability of the ACDs to keep PM10 level at or below the initial background level. RESULTS: In all conditions assessed in the dental clinic operatory, when both the chairside and portable ambient ACDs were functioning, an estimated effectiveness of 100% in capturing PM10 was achieved. In the MDC, in all conditions where the chairside ACD was used without the negative pressure module, an estimated effectiveness of 100% was also achieved. The simultaneous operation of the negative pressure module in the MDC, which led to a room negative pressure of -0.25 inch wc, reduced the chairside ACD's effectiveness in capturing aerosols. Conversely, the use of the WMAF in the MDC in combination with the chairside ACD further reduced exposure to PM10 below the initial background level. Nonetheless, in all conditions assessed in both settings (dental clinic operatory and MDC), larger visible aerosols were produced, often landing on the surrounding environment. A fair portion of these aerosols landed on the inside of the chairside ACD flange. CONCLUSIONS: This assessment suggests that the use of the tested chairside ACD, by capturing aerosols at the source of generation, had the greatest impact on reducing exposure of dental personnel to PM10 produced during dental procedures. This study also indicates that such exposure is further reduced with the addition of an ambient ACD. However, creating a negative pressure room as high as -0.25 inch wc can lead to air turbulence reducing the effectiveness of ACDs in capturing aerosols at the source. Furthermore, the presence of uncaptured droplets and spatter on the surrounding environment supports the need to complement the use of engineering controls with proper administrative controls and personal protective equipment, as recommended by governmental agencies and the scientific community for preventing the transmission of infection in health care settings.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , Pandemias/prevenção & controle , Aerossóis e Gotículas Respiratórios , Material Particulado , Odontologia
4.
ESMO Open ; 7(3): 100513, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35724624

RESUMO

BACKGROUND: Clinical trials allow development of innovative treatments and ameliorate the quality of clinical care in oncology. Data show that only a minority of patients are enrolled in clinical trials. We assessed enrolment in clinical trials and its correlates among women with early breast cancer. METHODS: We included 9516 patients with stage I-III breast cancer from the multicenter, prospective CANTO study (NCT01993498), followed-up until year 4 (Y4) post-diagnosis. We assessed factors associated with enrolment using multivariable logistic regression. In exploratory, propensity score matched analyses, we used multiple linear regression to evaluate the relationship of enrolment in clinical trials with the European Organisation for Research and Treatment of Cancer Quality Of Life (QoL) questionnaire (EORTC QLQ-C30) Summary Score and described clinical outcomes (distant disease event, invasive disease event, and death by any cause) according to enrolment. RESULTS: Overall, 1716 patients (18%) were enrolled in a clinical trial until Y4 post-diagnosis of breast cancer. Socioeconomic factors were not associated with enrolment. Centres of intermediate volume were most likely to enrol patients in clinical trials [versus low volume, odds ratio 1.45 (95% confidence interval (CI) 1.08-1.95), P = 0.0124]. Among 2118 propensity score matched patients, enrolment was associated with better QoL at Y4 (adjusted mean difference versus not enrolled 1.37, 95% CI 0.03-2.71, P = 0.0458), and clinical outcomes (enrolled versus not enrolled, distant disease event 7.3% versus 10.1%, P = 0.0206; invasive disease event 8.2% versus 10.5%, P = 0.0732; death by any cause 2.8% versus 3.7%, P = 0.2707). CONCLUSIONS: In this large study, one in five patients enrolled on a clinical trial until Y4 after diagnosis of early breast cancer. Geographical and centre-related factors were significantly associated with enrolment in clinical trials. Inclusion in clinical trials seemed associated with improved QoL and clinical outcomes. Access to innovation for early-stage breast cancer patients should be encouraged and facilitated by overcoming organizational and geographical barriers to recruitment.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/terapia , Feminino , Humanos , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários
5.
Front Chem ; 10: 1085868, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618862

RESUMO

New lead-vanadate based sorbents were synthesized with the aim to entrap and confine gaseous iodine in off-gas streams coming from reprocessing facilities of spent nuclear fuel. Their synthesis relies on the shaping of a lead-vanadate, lead sulfide and alginic acid mix as millimetric beads. These beads were calcined between 220°C and 500°C to remove organic alginic compounds template. However, according to the calcination temperature, lead sulfide could be partially oxidized, limiting iodine loading capacity. A compromise temperature between 290°C and 350°C was found to remove most of the alginic acid template and avoiding lead sulfide oxidation. These sorbents were tested for iodine trapping in static conditions at 60°C. They performed well with a sorption capacity up to 155 mg.g-1 by forming PbI2. Furthermore, these iodine-loaded sorbents could be easily converted into an iodine-containing lead-vanadate apatite matrix by spark plasma sintering. A dense sample was produced for a sintering temperature of 500°C under 70 MPa. Such a material could be suitable for radioactive iodine conditioning in deep geological disposal. Finally, lead-vanadate sorbents could provide an easy way to entrap and confine radioactive iodine from off-gas streams into a durable material within a few steps.

6.
Mar Environ Res ; 169: 105393, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34217095

RESUMO

The Kerguelen Islands (49°26'S, 69°50'E) represent a unique environment due to their geographical isolation, which protects them from anthropogenic pollution. The ability of the endemic mussel, part of the Mytilus complex, to cope with moderate heat stress was explored using omic tools. Transcripts involved in six major metabolic functions were selected and the qRT-PCR data indicated mainly changes in aerobic and anaerobic energy metabolism and stress response. Proteomic comparisons revealed a typical stress response pattern with cytoskeleton modifications and elements suggesting increased energy metabolism. Results also suggest conservation of protein homeostasis by the long-lasting presence of HSP while a general decrease in transcription is observed. The overall findings are consistent with an adaptive response to moderate stresses in mussels in good physiological condition, i.e. living in a low-impact site, and with the literature concerning this model species. Therefore, local blue mussels could be advantageously integrated into biomonitoring strategies, especially in the context of Global Change.


Assuntos
Mytilus edulis , Mytilus , Animais , Regiões Antárticas , Resposta ao Choque Térmico , Mytilus edulis/genética , Proteômica
7.
Braz J Med Biol Res ; 54(7): e10388, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34008752

RESUMO

Clinically relevant biomarkers are useful to determine cancer patients' prognosis and treatments. To discover new putative biomarkers, we performed in silico analysis of a 325-gene panel previously associated with breast epithelial cell biology and clinical outcomes. Sixteen public datasets of microarray samples representing 8 cancer types and a total of 3,663 patients' samples were used for the analyses. Feature selection was used to identify the best subsets of the 325 genes for each classification, and linear discriminant analysis was used to quantify the accuracy of the classifications. A subset of 102 of the 325 genes were found to be housekeeping (HK) genes, and the classifications were repeated using only the 102 HK subset. The 325-gene panel and 102 HK subset were able to distinguish colon, gastric, lung, ovarian, pancreatic, and prostate tumors and leukemia from normal adjacent tissue, and classify disease subtypes of breast and lung cancers and leukemia with 70% or higher accuracy. HK genes have been overlooked as potential biomarkers due to their relative stability. This study describes a set of HK genes as putative biomarkers applicable to multiple cancer types worth following in subsequent validation studies.


Assuntos
Neoplasias da Mama , Perfilação da Expressão Gênica , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Genes Essenciais , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo
8.
Br J Surg ; 108(3): 296-301, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33793719

RESUMO

BACKGROUND: Nipple-sparing mastectomy (NSM) with immediate breast reconstruction (IBR) is used increasingly when performing a prophylactic mastectomy. Few prospective studies have reported on complication rates. This complementary trial to the French prospective multicentre MAPAM trial aimed to evaluate the nipple-areola complex (NAC) necrosis rate in prophylactic NSM with IBR. METHODS: Patient characteristics and surgical data were recorded. Morbidity after prophylactic NSM with a focus on NAC necrosis was analysed. RESULTS: Among 59 women undergoing prophylactic NSM, 19 (32 per cent) of the incisions were partly on the NAC. Reconstructions were performed with 46 definitive implants and 13 expanders. The crude rate of postoperative complications was 25 per cent (15 patients). Complete NAC necrosis was reported in two women (3 per cent) and partial or total necrosis in nine (15 per cent). No NAC resection was necessary. Median BMI was lower in women with total or partial NAC necrosis compared with the others (20.0 versus 21.3 kg/m2 respectively; P = 0.034). CONCLUSION: Results of this prospective study confirm that prophylactic NSM with IBR is associated with a low risk of total NAC necrosis.


Assuntos
Mamoplastia , Necrose , Mamilos/patologia , Tratamentos com Preservação do Órgão , Mastectomia Profilática , Adulto , Idoso , Índice de Massa Corporal , Neoplasias da Mama/prevenção & controle , Feminino , França , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
9.
Clin Exp Immunol ; 204(1): 96-106, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33346915

RESUMO

A clearer understanding of the tumor immune microenvironment (TIME) in metastatic clear cell renal cell carcinoma (ccRCC) may help to inform precision treatment strategies. We sought to identify clinically meaningful TIME signatures in ccRCC. We studied tumors from 39 patients with metastatic ccRCC using quantitative multiplexed immunofluorescence and relevant immune marker panels. Cell densities were analyzed in three regions of interest (ROIs): tumor core, tumor-stroma interface and stroma. Patients were stratified into low- and high-marker density groups using median values as thresholds. Log-rank and Cox regression analyses while controlling for clinical variables were used to compare survival outcomes to patterns of immune cell distributions. There were significant associations with increased macrophage (CD68+ CD163+ CD206+ ) density and poor outcomes across multiple ROIs in primary and metastatic tumors. In primary tumors, T-bet+ T helper type 1 (Th1) cell density was highest at the tumor-stromal interface (P = 0·0021), and increased co-expression of CD3 and T-bet was associated with improved overall survival (P = 0·015) and survival after immunotherapy (P = 0·014). In metastatic tumor samples, decreased forkhead box protein 3 (FoxP3)+ T regulatory cell density correlated with improved survival after immunotherapy (P = 0·016). Increased macrophage markers and decreased Th1 T cell markers within the TIME correlated with poor overall survival and treatment outcomes. Immune markers such as FoxP3 showed consistent levels across the TIME, whereas others, such as T-bet, demonstrated significant variance across the distinct ROIs. These findings suggest that TIME profiling outside the tumor core may identify clinically relevant associations for patients with metastatic ccRCC.


Assuntos
Carcinoma de Células Renais/terapia , Imunoterapia/métodos , Neoplasias Renais/terapia , Microambiente Tumoral/imunologia , Adulto , Idoso , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/metabolismo , Feminino , Humanos , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Sistema Imunitário/patologia , Estimativa de Kaplan-Meier , Neoplasias Renais/imunologia , Neoplasias Renais/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Resultado do Tratamento
10.
Braz. j. med. biol. res ; 54(7): e10388, 2021. tab
Artigo em Inglês | LILACS | ID: biblio-1249319

RESUMO

Clinically relevant biomarkers are useful to determine cancer patients' prognosis and treatments. To discover new putative biomarkers, we performed in silico analysis of a 325-gene panel previously associated with breast epithelial cell biology and clinical outcomes. Sixteen public datasets of microarray samples representing 8 cancer types and a total of 3,663 patients' samples were used for the analyses. Feature selection was used to identify the best subsets of the 325 genes for each classification, and linear discriminant analysis was used to quantify the accuracy of the classifications. A subset of 102 of the 325 genes were found to be housekeeping (HK) genes, and the classifications were repeated using only the 102 HK subset. The 325-gene panel and 102 HK subset were able to distinguish colon, gastric, lung, ovarian, pancreatic, and prostate tumors and leukemia from normal adjacent tissue, and classify disease subtypes of breast and lung cancers and leukemia with 70% or higher accuracy. HK genes have been overlooked as potential biomarkers due to their relative stability. This study describes a set of HK genes as putative biomarkers applicable to multiple cancer types worth following in subsequent validation studies.


Assuntos
Humanos , Masculino , Neoplasias da Mama/genética , Perfilação da Expressão Gênica , Fenótipo , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Genes Essenciais
11.
Sci Rep ; 10(1): 6185, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32277096

RESUMO

The manufacturing cost of quantum cascade lasers is still a major bottleneck for the adoption of this technology for chemical sensing. The integration of Mid-Infrared sources on Si substrate based on CMOS technology paves the way for high-volume low-cost fabrication. Furthermore, the use of Si-based fabrication platform opens the way to the co-integration of QCL Mid-InfraRed sources with SiGe-based waveguides, enabling realization of optical sensors fully integrated on planar substrate. We report here the fabrication and the characterization of DFB-QCL sources using top metal grating approach working at 7.4 µm fully implemented on our 200 mm CMOS pilot line. These QCL featured threshold current density of 2.5 kA/cm² and a linewidth of 0.16 cm-1 with a high fabrication yield. This approach paves the way toward a Mid-InfraRed spectrometer at the silicon chip level.

12.
Encephale ; 46(3): 190-192, 2020 Jun.
Artigo em Francês | MEDLINE | ID: mdl-32151455

RESUMO

INTRODUCTION: All plastic surgeons are frequently faced with patients with Body Dysmorphic Disorder (BDD). However, no screening test exists in French to help the plastic surgeons to diagnose this disease. The Body Dysmorphic Disorder Questionnaire (BDDQ) is the Gold Standard to easily detect BDD in consultation with any non-psychiatric physician. The aim of this study was to translate and validate the BDDQ into French to help plastic surgeons to detect BDD before the surgery. This way, plastic surgeons will be able to provide an optimal medical care and to reduce the risk of psychiatric collapse. METHODS: We asked Katherine Philipps for her approval to use her BDDQ for our study, and thereafter we translated it respecting the criteria of the World Health Organization. We first evaluated the psychometric qualities of the BDDQ in French and then its reproducibility and its sensitivity to change. RESULTS: A French version of the BDDQ appeared to be reliable and comprehensible. The questionnaire has been tested on a sample of patients in plastic surgery consultation, at a T moment and a T plus one month to certify its reproducibility and its sensitivity to change. CONCLUSION: These results permit to claim that the French version of the BDDQ is now validated to detect patients with a BDD in a plastic surgery consultation.


Assuntos
Transtornos Dismórficos Corporais/diagnóstico , Programas de Rastreamento/métodos , Psicometria/métodos , Cirurgia Plástica/métodos , Inquéritos e Questionários , Adulto , Idoso , Comparação Transcultural , Feminino , França , Humanos , Programas de Rastreamento/normas , Pessoa de Meia-Idade , Psicometria/normas , Procedimentos de Cirurgia Plástica/psicologia , Encaminhamento e Consulta , Reprodutibilidade dos Testes , Inquéritos e Questionários/normas , Fatores de Tempo , Tradução , Adulto Jovem
13.
Rev Neurol (Paris) ; 176(1-2): 62-74, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31160075

RESUMO

Postictal syndrome (PIS) encompasses the clinical, biological, electroencephalographic (EEG) and magnetic resonance imaging (MRI) signs that follow the termination of a seizure. These signs occur as soon as the epileptic discharge ends, but might remain for a substantially long period of time, making them amenable to clinical observation. As a direct consequence, neurologists and intensivists are more frequently attending patients with PIS than during their seizure. Moreover, careful PIS documentation may help physicians to diagnose epileptic seizure from other non-epileptic disorders. Careful analysis of PIS could also be helpful to better characterize the seizure (seizure subtypes, and to some extent, the localization and/or lateralization of the seizure). This article aims to review the main clinical, biological, EEG and MRI components of PIS, discuss differential diagnoses and propose a general clinical attitude, based on the acronym "WAITTT": W for "Watch", to monitor and investigate PIS in order to provide relevant information on seizure, AIT for "Avoid Inappropriate Treatment", to underscore the risk carrying out unnecessary drug injections and intensive care procedures in the setting of a self-limited symptomatology, and TT for "Take Time", to keep in mind that time remains the clinician's best ally for treating patients with PIS.


Assuntos
Técnicas de Laboratório Clínico/métodos , Diagnóstico por Imagem/métodos , Epilepsia/diagnóstico , Convulsões/diagnóstico , Convulsões/etiologia , Biomarcadores/análise , Mapeamento Encefálico , Diagnóstico Diferencial , Eletroencefalografia , Humanos , Imageamento por Ressonância Magnética , Monitorização Fisiológica/métodos , Paralisia/complicações , Paralisia/diagnóstico , Síndrome
14.
Eur J Surg Oncol ; 44(6): 750-753, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29580734

RESUMO

AIM: Rectosigmoid resection is often performed during cytoreductive surgery for ovarian cancer, to achieve the goal of no residual tumour. Here, we evaluated the morbidity associated with rectosigmoid resection and the underlying risk factors. METHODS: We retrospectively assessed consecutive patients managed with rectosigmoid resection during cytoreductive surgery for ovarian cancer at our centre in Paris, France, between 2005 and 2013. All previously identified risk factors were analysed. Major complications were defined as grade III-IV in the Clavien-Dindo classification. RESULTS: Of 228 patients, 116 had primary and 112 interval surgery; 43/228 [18.9%]; experienced major complications, and these were more common after primary surgery [24.1% vs. 13.4%, p = .04]. The 69 patients who had rectosigmoid resection [33 primary vs. 36 interval surgery, p = .32] had a higher morbidity rate compared to the other patients [30.4% vs. 14.6%, p = .006]. The anastomotic leakage rate was 2.89%. By multivariate logistic regression, independent risk factors for morbidity were postmenopausal status [adjusted odds ratio (aOR), 13.7; 95% confidence interval (95%CI), 1.2;161.9], surgery after neoadjuvant chemotherapy [aOR, 4.4; 95%CI, 1.1;18.8], and peritoneal stripping of the left; paracolic gutter [aOR, 11.3; 95%CI, 2.3;54.3]. CONCLUSION: The morbidity of rectosigmoid resection during cytoreductive surgery for ovarian cancer seems acceptable. Ileostomy does not seem associated with a lower risk of major complications or adjuvant bevacizumab with a higher complication rate.


Assuntos
Procedimentos Cirúrgicos de Citorredução/métodos , Neoplasias Ovarianas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Proctocolectomia Restauradora/métodos , Medição de Risco/métodos , Idoso , Análise Fatorial , Feminino , França/epidemiologia , Humanos , Pessoa de Meia-Idade , Morbidade/tendências , Prognóstico , Estudos Retrospectivos , Fatores de Risco
15.
NPJ Schizophr ; 3(1): 31, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-28924227

RESUMO

xCT is the specific chain of the cystine/glutamate antiporter, which is widely reported to support anti-oxidant defenses in vivo. xCT is therefore at the crossroads between two processes that are involved in schizophrenia: oxidative stress and glutamatergic neurotransmission. But data from human studies implicating xCT in the illness and clarifying the upstream mechanisms of xCT imbalance are still scarce. Low glutathione (GSH) levels and genetic risk in GCLC (Glutamate-Cysteine Ligase Catalytic subunit), the gene of limiting synthesizing enzyme for GSH, are both associated with schizophrenia. In the present study, we aimed at determining if xCT regulation by the redox system is involved in schizophrenia pathophysiology. We assessed whether modulating GCLC expression impact on xCT expression and activity (i) in fibroblasts from patients and controls with different GCLC genotypes which are known to affect GCLC regulation and GSH levels; (ii) in rat brain glial cells, i.e., astrocytes and oligodendrocytes, with a knock-down of GCLC. Our results highlight that decreased GCLC expression leads to an upregulation of xCT levels in patients' fibroblasts as well as in astrocytes. These results support the implication of xCT dysregulation in illness pathophysiology and further indicate that it can result from redox changes. Additionally, we showed that these anomalies may already take place at early stages of psychosis and be more prominent in a subgroup of patients with GCLC high-risk genotypes. These data add to the existing evidence identifying the inflammatory/redox systems as important targets to treat schizophrenia already at early stages. SCHIZOPHRENIA: ANTIOXIDANT DEFICIT INCREASES A KEY NEUROTRANSMITTER TRANSPORTER: Deficit of antioxidant synthesis in schizophrenia leads to oxidative stress and changes in neurotransmitter transporter. Led by Kim Do, a team of researchers from Lausanne University in Switzerland investigated the role of the cell-surface transport protein xCT in schizophrenia. They found that an enzyme responsible for antioxidant production is disturbed in patients. This leads to decreased antioxidant levels and consequently to oxidative stress-i.e. the accumulation of reactive oxygen molecules, damaging the cells component and impairing cell functioning-which in turn affects the functioning of the antioxidant pathway, including xCT. xCT, which exports the neurotransmitter glutamate, is thus overproduced in schizophrenia. The resulting increase of neurotransmitter activity, alongside the increase in oxidative stress, is thought to play a major role in the pathophysiology of schizophrenia, including at early stages of the disease.

16.
Neurotoxicology ; 60: 116-124, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28467894

RESUMO

Exposure to environmental toxicants during vulnerable windows of brain development is suspected to raise the prevalence for neurological dysfunctions at later stages in life. Differentiation processes and changes in morphology, as well as a lack of physiological barriers, might be reasons that render a developing brain more susceptible to neurotoxicants than an adult. However, also the intrinsic capacity of cells to combat toxicant induced cellular stress might differ between the immature- and mature brain. In order to study whether this intrinsic protection capacity differs between immature and maturated brain cells we chose to study the maturation-dependent adverse effects of the known neurotoxicant Paraquat Dichloride (PQ) in 3D rat brain cell cultures. This in vitro system consists of the major brain cell types - neurons, astrocytes, oligodendrocytes and microglia - and over the time in vitro cultured cells undergo differentiation and maturation into a tissue-like organization. PQ was applied repeatedly over ten days in the sub-micromolar range, and effects were evaluated on neurons and glial cells. We observed that despite a higher PQ-uptake in mature cultures, PQ-induced adverse effects on glutamatergic-, GABAergic- and dopaminergic neurons, as assessed by gene expression and enzymatic activity, were more pronounced in immature cultures. This was associated with a stronger astrogliosis in immature- as compared to mature cultures, as well as perturbations of the glutathione-mediated defense against oxidative stress. Furthermore we observed evidence of microglial activation only in mature cultures, whereas immature cultures appeared to down-regulate markers for neuroprotective M2-microglial phenotype upon PQ-exposure. Taken together our results indicate that immature brain cell cultures have less intrinsic capacity to cope with cellular stress elicited by PQ as compared to mature cells. This may render immature brain cells more susceptible to the adverse effects of PQ.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Herbicidas/toxicidade , Paraquat/toxicidade , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/metabolismo , Células Cultivadas , Encefalite/induzido quimicamente , Mediadores da Inflamação , Microglia/efeitos dos fármacos , Microglia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo , Ratos Sprague-Dawley
17.
Int J Mycobacteriol ; 6(1): 108-110, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28317816

RESUMO

Hemophagocytic syndrome is a life-threatening disease characterized by the uncontrolled activation of macrophages, resulting in hemophagocytosis of blood cells in the bone marrow. A 20-year-old gravida at 23-week and 5-day gestation was admitted to hospital to evaluate fever up to 104°F of unknown origin, moderate cytopenia, and elevated levels of liver enzymes. Bone marrow biopsy confirmed hemophagocytic syndrome, and polymerase chain reaction came back positive for Mycobacterium tuberculosis. Supportive care and tuberculosis treatment resulted in clinical improvement. At 27 weeks and 5 days, premature rupture of the membranes occurred, and because of the high probability of reactivating the hemophagocytic syndrome, a cesarean section was performed at 29-week and 2-day gestation. Hemophagocytic syndrome is an uncommon disease which rarely appears during pregnancy. Early diagnosis and treatment can save both maternal and fetal lives.


Assuntos
Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/etiologia , Mycobacterium tuberculosis/isolamento & purificação , Complicações Infecciosas na Gravidez , Tuberculose/complicações , Cesárea , Feminino , Febre , Humanos , Recém-Nascido , Unidades de Terapia Intensiva , Linfo-Histiocitose Hemofagocítica/microbiologia , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase , Gravidez , Tuberculose/microbiologia , Adulto Jovem
18.
Radiat Prot Dosimetry ; 173(1-3): 55-62, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27885091

RESUMO

Radiological protection is a matter of concern for members of the public and thus national authorities are more likely to trust the quality of radioactivity data provided by accredited laboratories using common standards. Normative approach based on international standards aims to ensure the accuracy or validity of the test result through calibrations and measurements traceable to the International System of Units. This approach guarantees that radioactivity test results on the same types of samples are comparable over time and space as well as between different testing laboratories. Today, testing laboratories involved in radioactivity measurement have a set of more than 150 international standards to help them perform their work. Most of them are published by the International Standardization Organization (ISO) and the International Electrotechnical Commission (IEC). This paper reviews the most essential ISO standards that give guidance to testing laboratories at different stages from sampling planning to the transmission of the test report to their customers, summarizes recent activities and achievements and present the perspectives on new standards under development by the ISO Working Groups dealing with radioactivity measurement in connection with radiological protection.


Assuntos
Exposição à Radiação , Proteção Radiológica , Meio Ambiente , Exposição Ambiental , Humanos , Laboratórios , Radioatividade , Padrões de Referência
19.
Scand J Med Sci Sports ; 27(10): 1157-1165, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27540899

RESUMO

This study aims to test the efficacy of text messaging cues (SMS) to promote physical activity (PA) habit formation in the workplace. Employees (N = 49; 28 females and 21 males, Mage = 47.5 ± 8.29 years) were randomized into two parallel groups: a PA group enrolled in a 28-week supervised PA program and a PA+SMS group enrolled in the same PA program with text messaging cues received before their PA sessions. The exercise habit was assessed every week from self-reports on an online application. PA maintenance and several physical fitness measures were also assessed prior to and after the intervention to evaluate its general impact. Mixed model analysis of the 603 observations indicated a small but significant effect of the SMS cues on the speed at which participants engaged in PA behaviors, as the significant interaction effect revealed that the slope of the exercise habit over time was slightly steeper in the PA+SMS group (B = 0.0462, P = 0.0001) than in the PA group (B = 0.0216, P = 0.01). SMS delivery had a marginal effect on the maintenance of PA behaviors 1 year after the intervention. The results suggest that text messaging can help to form PA habits at the workplace and might facilitate long-term maintenance of PA behaviors.


Assuntos
Exercício Físico , Promoção da Saúde/métodos , Envio de Mensagens de Texto , Local de Trabalho , Adulto , Feminino , França , Hábitos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Aptidão Física
20.
Transl Psychiatry ; 6(7): e859, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27459724

RESUMO

Several lines of evidence implicate the fornix-hippocampus circuit in schizophrenia. In early-phase psychosis, this circuit has not been extensively investigated and the underlying mechanisms affecting the circuit are unknown. The hippocampus and fornix are vulnerable to oxidative stress at peripuberty in a glutathione (GSH)-deficient animal model. The purposes of the current study were to assess the integrity of the fornix-hippocampus circuit in early-psychosis patients (EP), and to study its relationship with peripheral redox markers. Diffusion spectrum imaging and T1-weighted magnetic resonance imaging (MRI) were used to assess the fornix and hippocampus in 42 EP patients compared with 42 gender- and age-matched healthy controls. Generalized fractional anisotropy (gFA) and volumetric properties were used to measure fornix and hippocampal integrity, respectively. Correlation analysis was used to quantify the relationship of gFA in the fornix and hippocampal volume, with blood GSH levels and glutathione peroxidase (GPx) activity. Patients compared with controls exhibited lower gFA in the fornix as well as smaller volume in the hippocampus. In EP, but not in controls, smaller hippocampal volume was associated with high GPx activity. Disruption of the fornix-hippocampus circuit is already present in the early stages of psychosis. Higher blood GPx activity is associated with smaller hippocampal volume, which may support a role of oxidative stress in disease mechanisms.


Assuntos
Fórnice/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Transtornos Psicóticos/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Adulto , Anisotropia , Transtorno Bipolar/sangue , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/patologia , Estudos de Casos e Controles , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/patologia , Imagem de Tensor de Difusão , Feminino , Fórnice/patologia , Glutationa/sangue , Glutationa Peroxidase/sangue , Hipocampo/patologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Estresse Oxidativo , Transtornos Psicóticos/sangue , Transtornos Psicóticos/patologia , Esquizofrenia/sangue , Esquizofrenia/patologia , Adulto Jovem
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