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1.
Nature ; 594(7863): 369-373, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34135523

RESUMO

The central challenge in building a quantum computer is error correction. Unlike classical bits, which are susceptible to only one type of error, quantum bits (qubits) are susceptible to two types of error, corresponding to flips of the qubit state about the X and Z directions. Although the Heisenberg uncertainty principle precludes simultaneous monitoring of X- and Z-flips on a single qubit, it is possible to encode quantum information in large arrays of entangled qubits that enable accurate monitoring of all errors in the system, provided that the error rate is low1. Another crucial requirement is that errors cannot be correlated. Here we characterize a superconducting multiqubit circuit and find that charge noise in the chip is highly correlated on a length scale over 600 micrometres; moreover, discrete charge jumps are accompanied by a strong transient reduction of qubit energy relaxation time across the millimetre-scale chip. The resulting correlated errors are explained in terms of the charging event and phonon-mediated quasiparticle generation associated with absorption of γ-rays and cosmic-ray muons in the qubit substrate. Robust quantum error correction will require the development of mitigation strategies to protect multiqubit arrays from correlated errors due to particle impacts.

2.
Mol Psychiatry ; 26(5): 1659-1669, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32076115

RESUMO

Mechanisms of neuroimmune and mitochondrial dysfunction have been repeatedly implicated in autism spectrum disorder (ASD). To examine these mechanisms in ASD individuals, we measured the in vivo expression of the 18 kDa translocator protein (TSPO), an activated glial marker expressed on mitochondrial membranes. Participants underwent scanning on a simultaneous magnetic resonance-positron emission tomography (MR-PET) scanner with the second-generation TSPO radiotracer [11C]PBR28. By comparing TSPO in 15 young adult males with ASD with 18 age- and sex-matched controls, we showed that individuals with ASD exhibited lower regional TSPO expression in several brain regions, including the bilateral insular cortex, bilateral precuneus/posterior cingulate cortex, and bilateral temporal, angular, and supramarginal gyri, which have previously been implicated in autism in functional MR imaging studies. No brain region exhibited higher regional TSPO expression in the ASD group compared with the control group. A subset of participants underwent a second MR-PET scan after a median interscan interval of 3.6 months, and we determined that TSPO expression over this period of time was stable and replicable. Furthermore, voxelwise analysis confirmed lower regional TSPO expression in ASD at this later time point. Lower TSPO expression in ASD could reflect abnormalities in neuroimmune processes or mitochondrial dysfunction.


Assuntos
Transtorno do Espectro Autista , Receptores de GABA/genética , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/genética , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Receptores de GABA/metabolismo , Adulto Jovem
3.
Phys Rev Lett ; 124(25): 253203, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32639777

RESUMO

Increasing ellipticity usually suppresses the recollision probability drastically. In contrast, we report on a recollision channel with large return energy and a substantial probability, regardless of the ellipticity. The laser envelope plays a dominant role in the energy gained by the electron, and in the conditions under which the electron comes back to the core. We show that this recollision channel efficiently triggers various nonlinear and nonperturbative phenomena-such as multiple ionization-with an elliptically polarized pulse.

4.
Neuroimage ; 185: 641-653, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30017787

RESUMO

While the main neural networks are in place at term birth, intense changes in cortical microstructure occur during early infancy with the development of dendritic arborization, synaptogenesis and fiber myelination. These maturational processes are thought to relate to behavioral acquisitions and the development of cognitive abilities. Nevertheless, in vivo investigations of such relationships are still lacking in healthy infants. To bridge this gap, we aimed to study the cortical maturation using non-invasive Magnetic Resonance Imaging, over a largely unexplored period (1-5 post-natal months). In a first univariate step, we focused on different quantitative parameters: longitudinal relaxation time (T1), transverse relaxation time (T2), and axial diffusivity from diffusion tensor imaging (λ//) These individual maps, acquired with echo-planar imaging to limit the acquisition time, showed spatial distortions that were first corrected to reliably match the thin cortical ribbon identified on high-resolution T2-weighted images. Averaged maps were also computed over the infants group to summarize the parameter characteristics during early infancy. In a second step, we considered a multi-parametric approach that leverages parameters complementarity, avoids reliance on pre-defined regions of interest, and does not require spatial constraints. Our clustering strategy allowed us to group cortical voxels over all infants in 5 clusters with distinct microstructural T1 and λ// properties The cluster maps over individual cortical surfaces and over the group were in sound agreement with benchmark post mortem studies of sub-cortical white matter myelination, showing a progressive maturation of 1) primary sensori-motor areas, 2) adjacent unimodal associative cortices, and 3) higher-order associative regions. This study thus opens a consistent approach to study cortical maturation in vivo.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/crescimento & desenvolvimento , Rede Nervosa/crescimento & desenvolvimento , Encéfalo/diagnóstico por imagem , Análise por Conglomerados , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Lactente , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem
5.
Nature ; 502(7473): 659-63, 2013 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-24153178

RESUMO

The on-demand generation of pure quantum excitations is important for the operation of quantum systems, but it is particularly difficult for a system of fermions. This is because any perturbation affects all states below the Fermi energy, resulting in a complex superposition of particle and hole excitations. However, it was predicted nearly 20 years ago that a Lorentzian time-dependent potential with quantized flux generates a minimal excitation with only one particle and no hole. Here we report that such quasiparticles (hereafter termed levitons) can be generated on demand in a conductor by applying voltage pulses to a contact. Partitioning the excitations with an electronic beam splitter generates a current noise that we use to measure their number. Minimal-excitation states are observed for Lorentzian pulses, whereas for other pulse shapes there are significant contributions from holes. Further identification of levitons is provided in the energy domain with shot-noise spectroscopy, and in the time domain with electronic Hong-Ou-Mandel noise correlations. The latter, obtained by colliding synchronized levitons on a beam splitter, exemplifies the potential use of levitons for quantum information: using linear electron quantum optics in ballistic conductors, it is possible to imagine flying-qubit operation in which the Fermi statistics are exploited to entangle synchronized electrons emitted by distinct sources. Compared with electron sources based on quantum dots, the generation of levitons does not require delicate nanolithography, considerably simplifying the circuitry for scalability. Levitons are not limited to carrying a single charge, and so in a broader context n-particle levitons could find application in the study of full electron counting statistics. But they can also carry a fraction of charge if they are implemented in Luttinger liquids or in fractional quantum Hall edge channels; this allows the study of Abelian and non-Abelian quasiparticles in the time domain. Finally, the generation technique could be applied to cold atomic gases, leading to the possibility of atomic levitons.

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.
Rev Epidemiol Sante Publique ; 67(5): 337-344, 2019 Sep.
Artigo em Francês | MEDLINE | ID: mdl-31204149

RESUMO

BACKGROUND: Based on the observation of the misuse of ICD-10 to code the diagnoses in the RIM-P (lack of completeness, conformity and diversity), the Technical Agency for information on Hospital Care (ATIH), which provides tools for collecting medical information, conducted two actions in 2016. First, a chapter devoted to the instructions of coding has been written in the methodological guide of production of the RIM-P, second, a variable "type psy" was added to the ICD-10 nomenclature's file framing ICD-10 coding in the RIM-P. The purpose of this study is to describe the quality of diagnosis coding using ICD-10 in the RIM-P in 2015 and 2016. METHODS: The quality of diagnosis coding using ICD-10 in the summaries of activity of the RIM-P national databases was described in 2015 and 2016. The study focused on the completeness, the conformity and the diversity of coding. RESULTS: Between 2015 and 2016, the percentage of summaries without primary diagnosis ("DP") decreased slightly for full-time (5.2% vs. 3.8%), part-time (6.3% vs. 4.9%) inpatient stays and outpatient care (9.9% vs. 8.9%). ICD-10 codes used to code DP or associated diagnosis ("DA"), while prohibited, mainly belong to Chapter V Mental and behavioral disorders. Per year, only one-third of the summaries and one-half of patients had two or more ICD-10 codes reported for inpatient stays (one-fifth of the summaries and one-fourth of the patients for outpatient care). In addition, per year and per facility, the average number of distinct ICD-10 codes used to fill "DP" or "DA" was approximately half as important in part-time hospitalization, as in full-time hospitalization or for outpatient care. Moreover, 90% of the health facilities used<550 distinct ICD-10 codes in full-time inpatient stays,<270 in part-time inpatient stays and<950 for outpatient care to code the "DP" or the "DA". The diversity of ICD-10 codes used was low and similar between 2015 and 2016, especially to describe the socio-economic environment, resistance to treatment or non-compliance. CONCLUSION: This study emphasizes the need for a collective effort to improve the diversity of the diagnoses' coding in the RIM-P.


Assuntos
Confiabilidade dos Dados , Classificação Internacional de Doenças/normas , Sistemas Computadorizados de Registros Médicos/normas , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia , Assistência Ambulatorial/normas , Assistência Ambulatorial/estatística & dados numéricos , Bases de Dados Factuais/normas , Bases de Dados Factuais/estatística & dados numéricos , França/epidemiologia , Fidelidade a Diretrizes/normas , Fidelidade a Diretrizes/estatística & dados numéricos , Sistemas de Informação Hospitalar/organização & administração , Sistemas de Informação Hospitalar/normas , Hospitalização/estatística & dados numéricos , Humanos , Sistemas Computadorizados de Registros Médicos/organização & administração , Sistemas Computadorizados de Registros Médicos/estatística & dados numéricos , Transtornos Mentais/classificação , Alta do Paciente/normas , Alta do Paciente/estatística & dados numéricos , Qualidade da Assistência à Saúde/organização & administração , Qualidade da Assistência à Saúde/normas
8.
Ann Oncol ; 29(3): 640-645, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29236940

RESUMO

Background: While deregulation of the cyclin D1-CDK4/6-retinoblastoma pathway is common in hormone receptor positive (HR+) breast cancer, Rb is usually intact in HR+ breast cancer, and targeted CDK 4/6 inhibitors that act upstream of Rb, are routinely being utilized in clinical practice. However, factors that can lead to clinical resistance to CDK 4/6 inhibitors are not known. Patients and methods: We identified patients who had pre- and post-genotyping in tissue and peripheral blood samples after receiving CDK 4/6 inhibitors. Genotyping was carried out in tumor tissue or blood collected before start of CDK 4/6 inhibitor and after disease progression on CDK 4/6 inhibitor, covering more than 90% of the coding region in RB1. Results: We identified detectable acquired RB1 mutations in circulating tumor DNA (ctDNA) after exposure to CDK4/6 inhibitor (palbociclib, palbociclib, ribociclib) for 5, 8, and 13 months, respectively, in three patients. The RB1 mutations included substitution in donor splicing site of exon 8 of the RB1 gene in patient #1; substitution in donor splicing site of exon 22 of RB1 gene, exon 19 deletion, exon 3 insertion in patient #2; and RB1 exon 16 H483Y mutation in patient #3. None of these RB1 mutations were present in the pre-CDK 4/6 specimen highlighting these molecular alterations, which lead to functional loss of Rb1, likely emerged under selective pressure from the CDK4/6 inhibitor potentially confering therapeutic resistance. Conclusion: This is the first clinical report to describe the emergence of somatic RB1 mutations after exposure to palbociclib or ribociclib, in patients with metastatic breast cancer. Further research is needed to validate these findings, identify how these mutations temporally emerge under selective pressure of CDK 4/6 inhibitor, and develop rational therapeutic strategies.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Ligação a Retinoblastoma/efeitos dos fármacos , Proteínas de Ligação a Retinoblastoma/genética , Ubiquitina-Proteína Ligases/efeitos dos fármacos , Ubiquitina-Proteína Ligases/genética , Idoso , Aminopiridinas/uso terapêutico , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Purinas/uso terapêutico , Piridinas/uso terapêutico
9.
Phys Rev Lett ; 121(11): 113202, 2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30265122

RESUMO

Electron motion in combined strong laser and Coulomb fields is central to laser-matter interactions. By mapping this problem onto the motion of a guiding center, we derive a reduced model which naturally embeds important Coulomb effects such as focusing and asymmetry, and clearly distinguishes direct versus rescattered electron ionization processes. We demonstrate the power of this tool by unraveling the bifurcation in photoelectron momentum distributions seen in experiments.

10.
J Eur Acad Dermatol Venereol ; 32(1): 145-151, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29055158

RESUMO

BACKGROUND: Hyperhidrosis is a common medical condition which can have a significant impact on quality of life. Umeclidinium (UMEC) is a long-acting muscarinic antagonist (LAMA) developed as a dermal formulation. OBJECTIVES: This 2-week, double-blind, randomized, vehicle-controlled study evaluated systemic exposure, safety and tolerability of topically administered UMEC in subjects with primary axillary hyperhidrosis. Clinical effect was a secondary objective, measured by gravimetry and the hyperhidrosis disease severity scale (HDSS). Vehicle was included to evaluate safety. METHODS: Twenty-three subjects were randomized to either 1.85% UMEC (N = 18) or vehicle (N = 5) once daily. RESULTS: Measurable plasma concentrations were observed in 78% of subjects after the treatment. Nine subjects (50%) on UMEC and two subjects (40%) on vehicle reported AEs, most commonly application site reactions. At Day 15, seven subjects (41%) in UMEC and two subjects (40%) in vehicle had at least a 50% reduction in sweat production. Eight subjects (47%) in UMEC and one subject (20%) in vehicle had at least a two-point reduction in HDSS. No comparisons of treatment arms were planned prospectively. CONCLUSIONS: The measurable exposure, acceptable safety and preliminary clinical activity observed in this proof-of-concept study suggest the potential clinical utility of topical UMEC in subjects with axillary hyperhidrosis.


Assuntos
Hiperidrose/tratamento farmacológico , Antagonistas Muscarínicos/efeitos adversos , Quinuclidinas/efeitos adversos , Sudorese/efeitos dos fármacos , Administração Cutânea , Adulto , Axila , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antagonistas Muscarínicos/sangue , Antagonistas Muscarínicos/farmacocinética , Antagonistas Muscarínicos/uso terapêutico , Estudo de Prova de Conceito , Quinuclidinas/sangue , Quinuclidinas/farmacocinética , Quinuclidinas/uso terapêutico , Índice de Gravidade de Doença , Adulto Jovem
11.
Artigo em Francês | MEDLINE | ID: mdl-29857922

RESUMO

BACKGROUND: French post-acute care and rehabilitation facilities describe and code their activity through the Program for Medicalization of Information Systems (PMSI). A new specific catalogue of rehabilitation procedures (CSARR) has been implemented to code rehabilitation acts since 2013. This study aimed to assess the coherence of the coding of the rehabilitation acts using the CSARR two years after its establishment through the analyze of 3 main items regarding patients and therapists. METHODS: We analyzed the use of CSARR for coding rehabilitation acts from the PMSI national database for post-acute care and rehabilitation, in 2015. Analyses were made on specific items characterizing rehabilitation acts: "number of patients", "type of therapists" and "number of therapists". RESULTS: There were 72,014,731 rehabilitation acts coded in 2015 using CSARR nomenclature; 86% were individual rehabilitation acts. All acts of CSARR, except one, were used to describe rehabilitation activities. Physiotherapists coded the majority of rehabilitation acts (47%), then nurses (14%). Coding errors were identified as the "number of patients", coded with more than one patient for individual acts (13% of the acts) or with less than 2 patients for groups (6% of the acts), or the "number of therapists" coded with only one therapist for rehabilitation acts requiring several professionals. CONCLUSION: This first assessment indicated a good level of appropriation of the CSARR coding rules in the national PMSI database by post-acute care and rehabilitation facilities. However, a simplification of this catalogue and therapist training could increase the quality of the rehabilitation data.

12.
Phys Chem Chem Phys ; 18(40): 28091-28100, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27711399

RESUMO

The photoswitching and competitive processes of the referent photochromic diarylethene derivative 1,2-bis(2,4-dimethyl-5-phenyl-3-thienyl)perfluorocyclopentene (DTE) and a novel bridged analog DTE-m5 have been investigated by state-of-the-art TD-DFT calculations and ultrafast spectroscopy supported by advanced chemometric data treatments. Focusing on DTE, the overall deactivation pathway of both antiparallel (AP) and parallel (P) conformers of the open form (OF) (1 : 1 in solution) has been resolved and rationalized starting from the Franck-Condon (FC) region to the ground state recovery. For the photo-excited P conformer, after ultrafast relaxation (∼200 fs) towards the S1 relaxed state, an expected ISC occurred (55 ps) to produce a triplet state, 3P, the latter relaxing within 2.5 µs. Concerning the AP conformer, the photocyclization reaction is reported to proceed immediately (100 fs) starting from the FC region while the relaxed singlet state is populated in parallel. For the first time, we discovered that the latter state evolves through an unexpected ISC process (1 ps) giving rise to a second triplet state,3AP. For DTE-m5, by slightly constraining the molecule with the bridge, this triplet becomes reactive and participates in the formation of 10% of closed form (CF) probably through an adiabatic mechanism. Concerning the photoreversion, in accordance with the literature, we report on a two-step process, a 190 fs vibrational relaxation followed by a 6 ps ring-opening reaction. For the overall species at the singlet or triplet manifold, the use of advanced MCR-ALS allows us to obtain specific spectral signatures. This study is therefore a new step within the comprehension of DTE photochemistry.

13.
J Musculoskelet Neuronal Interact ; 16(3): 247-55, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27609039

RESUMO

OBJECTIVES: Knowledge of physiological variations of bone mineral density (BMD) in newborns and infants is necessary to evaluate pathological changes associated with fractures. Limited reference data for children under 5 years old are available. This study provides normative data of lumbar BMD for the Lunar Prodigy in young children under 5 years old. SUBJECTS AND METHODS: We assessed cross-sectionally 155 healthy children (77 boys, 80% Caucasian), ranging in age from newborn to the age of 5 years. Lumbar bone mineral content (BMC) and areal BMD were measured by dual-energy X-ray absorptiometry using a Lunar Prodigy absorptiometer. Volumetric BMD was calculated using the Kroeger and Carter methods. RESULTS: BMC and areal BMD increased from birth to 5 years (p<0.001). Volumetric BMD did not change with age. BMD and BMC correlated with age, weight and height (R(2)≥0.85 for all), with a maximum gain between the ages of 1 and 4 years, which did not follow the same pattern as height velocity. We did not find significant sex difference for any of the three measured parameters. CONCLUSION: This study provides normative data for lumbar spine densitometry of infants and young children using the Lunar Prodigy DXA system.


Assuntos
Densidade Óssea/fisiologia , Vértebras Lombares/fisiologia , Absorciometria de Fóton , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Vértebras Lombares/diagnóstico por imagem , Masculino , Valores de Referência
14.
Neuroimage ; 99: 342-56, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24862070

RESUMO

Developmental research, as well as paediatric clinical activity crucially depends on non-invasive and painless brain recording techniques, such as electroencephalography (EEG), and near infrared spectroscopy (NIRS). However, both of these techniques measure cortical activity from the scalp without precise knowledge of the recorded cerebral structures. An accurate and reliable mapping between external anatomical landmarks and internal cerebral structures is therefore fundamental to localise brain sources in a non-invasive way. Here, using MRI, we examined the relations between the 10-20 sensor placement system and cerebral structures in 16 infants (3-17 weeks post-term). We provided an infant template parcelled in 94 regions on which we reported the variability of sensors locations, concurrently with the anatomical variability of six main cortical sulci (superior and inferior frontal sulcus, central sulcus, sylvian fissure, superior temporal sulcus, and intraparietal sulcus) and of the distances between the sensors and important cortical landmarks across these infants. The main difference between infants and adults was observed for the channels O1-O2, T5-T6, which projected over lower structures than in adults. We did not find any asymmetry in the distances between the scalp and the brain envelope. However, because of the Yakovlean torque pushing dorsally and frontally the right sylvian fissure, P3-P4 were not at the same distance from the posterior end of this structure. This study should help to refine hypotheses on functional cognitive development by providing an accurate description of the localization of standardised channels relative to infants' brain structures. Template and atlas are publicly available on our Web site (http://www.unicog.org/pm/pmwiki.php/Site/InfantTemplate).


Assuntos
Eletroencefalografia/normas , Couro Cabeludo/anatomia & histologia , Adulto , Pontos de Referência Anatômicos , Atlas como Assunto , Encéfalo/anatomia & histologia , Mapeamento Encefálico , Córtex Cerebral/anatomia & histologia , Eletrodos , Feminino , Humanos , Individualidade , Lactente , Recém-Nascido , Masculino , Neuroimagem/normas , Padrões de Referência
15.
Environ Sci Technol ; 48(15): 8664-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24978298

RESUMO

This research compared the bioavailability of Fe associated with two forms of the hydrous Fe oxyhydroxide nanomineral ferrihydrite (Fh)--the smaller (1-3 nm), less ordered 2-line (2L) phase and the slightly larger, (2-6 nm) more ordered 6-line (6L) phase--to the common aerobic soil bacterium Pseudomonas mendocina ymp. P. mendocina can acquire Fe from minerals using high-affinity Fe(III) binding ligands known as siderophores and a cell-associated metalloreductase that requires direct cell-mineral contact. Wild-type (WT) P. mendocina and a siderophore(-) mutant were used to monitor siderophore -related and -independent Fe acquisition from 2L and 6L Fh. Both WT and mutant strains acquired Fe from Fh, although Fe acquisition and growth were substantially greater on the 2L phase than on the 6L phase. In the absence of bacteria, copious quantities of the biofilm exopolysaccharide alginate slightly promoted dissolution of 2L and 6L Fh. In biotic experiments, added alginate slightly enhanced growth and Fe acquisition from 6L Fh but not from 2L Fh. Recent research has led to an emerging understanding that Fe-oxide nanoparticle structure, stability, and reactivity are highly sensitive to size at the nanoscale; this research emphasizes how subtle differences in nanoparticle size-related properties can also affect bioavailability.


Assuntos
Alginatos , Compostos Férricos/metabolismo , Ferro/metabolismo , Pseudomonas mendocina/metabolismo , Sideróforos/metabolismo , Bactérias/metabolismo , Disponibilidade Biológica , Ácido Glucurônico , Ácidos Hexurônicos , Minerais/metabolismo , Nanopartículas/metabolismo , Pseudomonas mendocina/crescimento & desenvolvimento
16.
Pediatr Transplant ; 18(5): E146-51, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24815678

RESUMO

We describe here a two-yr-old boy with biliary RMS successfully treated by chemotherapy and LT. The child presented with obstructive jaundice at 20 months of age. A mildly vascularized, non-calcified, partially cystic lesion was visualized in the left hepatic lobe. Solid infiltration of the common bile duct and of both left and right hepatic ducts was suspected. Liver biopsy suggested a botryoid-type embryonal RMS originating from the biliary tract. After extrahepatic spread of the tumor was excluded, a biliary drain was applied and neoadjuvant chemotherapy was started. After the treatment, although reduced in volume, the mass was still unresectable without aggressive surgery and gross residual disease. LT with a reduced segment II/III graft was performed four months after diagnosis. The patient received six cycles of adjuvant chemotherapy, and he is alive and recurrence-free 48 months post-transplantation. A posteriori, the transplant might have possibly been avoided with an aggressive resection with biliary reconstruction. Nevertheless, although the risk of the transplant has to be balanced against the chemoresponsiveness of the tumor, the four-yr disease-free survival of this patient suggests that, when coupled with effective chemotherapy, transplantation might be considered a potential treatment for unresectable biliary RMS.


Assuntos
Neoplasias do Sistema Biliar/terapia , Transplante de Fígado , Rabdomiossarcoma/terapia , Antineoplásicos/uso terapêutico , Neoplasias do Sistema Biliar/diagnóstico por imagem , Biópsia , Quimioterapia Adjuvante/métodos , Pré-Escolar , Intervalo Livre de Doença , Sobrevivência de Enxerto , Humanos , Terapia de Imunossupressão , Fígado/patologia , Masculino , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia , Rabdomiossarcoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
17.
Poult Sci ; 93(9): 2220-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25002547

RESUMO

The aim of this trial was to study the influence of choice feeding and cereal type (corn or triticale) during the finishing period on performance of ducks. In total, 624 one-day-old male mule ducks (Cairina moschata × Anas platyrhynchos) were divided into 3 groups differing in the diet they received between 56 and 84 d of age: a commercial complete pelleted diet (control group; AMEn 12.1 MJ/kg, CP 15%), or corn whole seeds (AMEn 14.4 MJ/kg, CP 7.3%) and protein-rich pellets (AMEn 9.9 MJ/kg, CP 22.7%) in 2 separated feeders [choice feeding with corn (CFC) group]; or triticale whole seeds (AMEn 13.0 MJ/kg, CP 10.5%) and protein-rich pellets (AMEn 11.2 MJ/kg, CP 19.5%) in 2 separated feeders [choice feeding with triticale (CFT) group]. From 85 to 96 d, 96 birds/group were overfed with corn. Feed intake (complete pellets or cereal and protein-rich pellets) per pen was measured at 60, 62, 65, 69, 78, and 84 d of age. Body weight and body traits were measured at 56 to 84 d of age. Over the entire period, from 56 to 84 d, the feed intake of the CFC group was 7% lower than the control group, and 5% lower than that in the CFT group (P = 0.002). Whatever the diet tested, at 56 and 84 d of age, the BW (4,099 and 4,779 g, P = 0.42 and P = 0.35, respectively) and the carcass traits (P > 0.05) of ducks were similar in the 3 groups. During and after overfeeding, the performances of the ducks were also similar (P > 0.05). The present results suggest that CFC during the finishing period is a solution to reduce the cost of diet destined to ducks. Indeed, using locally grown grains could reduce the economic and environmental impacts of duck feeding, reducing the transportation and crushing processes.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Dieta/veterinária , Patos/fisiologia , Grão Comestível/metabolismo , Zea mays/metabolismo , Ração Animal/análise , Ração Animal/economia , Animais , Composição Corporal , Peso Corporal , Patos/crescimento & desenvolvimento , Masculino
18.
Odontostomatol Trop ; 37(147): 27-33, 2014 Sep.
Artigo em Francês | MEDLINE | ID: mdl-25975065

RESUMO

BACKGROUND: During its clinical practice, the dentist is often faced with issues concerning the determination of teeth shade. This step is considered sensitive by numerous clinicians and dental laboratories. The objective of this study was to test the ability of professional dentists to visually determine the teeth color. MATERIAL AND METHODS: Eleven dentists classified 35 unmarked samples according to their hue, chroma and value from 2 standardized tooth shade guides Ivoclar-Vivadent (Chromascop) et Vita (3D Master). The ratio between the number of matching samples and the total amount of samples from each group was calculated and converted to a score between 0 and 10. RESULTS: Better scores were obtained for value and chroma with the 3D Master shade guide than with the Chromascop shade guide (p < 0.001). The opposite result was obtained for the hue (p < 0.05). Globally, better results were obtained for the value and chroma, the hue being the most difficult item to evaluate. A satisfying "color perception" was observed in 69% of the cases. CONCLUSION: The results of this study argue in favor of a specific training for tooth shade determination in Odontology.


Assuntos
Percepção de Cores/fisiologia , Odontólogos , Dente/anatomia & histologia , Cor , Planejamento de Prótese Dentária , Feminino , Humanos , Luz , Masculino , Projetos Piloto , Pigmentação em Prótese/instrumentação , Reprodutibilidade dos Testes
19.
Insights Imaging ; 15(1): 135, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853199

RESUMO

OBJECTIVES: To compare the magnetic resonance imaging (MRI) and Doppler ultrasound (DUS) findings with the pathological findings of soft tissue vascular tumors (STVTs) according to the 2018 ISSVA (International Society for the Study of Vascular Anomalies) classification to differentiate vascular tumors from vascular malformations. METHODS: This retrospective study included patients with STVTs who underwent contrast-enhanced MRI and pathological analysis at our hospital between 2010 and 2020. The presumptive diagnosis based on the on-site imaging and histological analysis was compared with imaging and histological analysis conducted off-site utilizing the ISSVA criteria. RESULTS: This study included 31 patients with 31 vascular tumors located in the head and neck (n = 3), trunk (n = 2), and extremities (n = 26). The off-site pathological analysis confirmed benign vascular tumors in 54.8% of cases (non-involuting congenital hemangioma: 35.5%; epithelioid hemangioma: 13%; pyogenic granuloma: 3%; and spindle cell hemangioma: 3%). Based on the off-site histological analysis, 25.8% were reclassified as having a vascular malformation whereas three had other benign lesions. Only phleboliths were associated with a vascular malformation (p = 0.03). The concordance between off-site MRI and pathological findings was fair (k = 0.3902 (0.0531-0.7274)), whereas that between on-site and off-site pathological analyses was poor (k = -0.0949 (-0.4661 to 0.2763)). CONCLUSION: Benign vascular tumors have non-specific imaging features on imaging with some overlap with atypical vascular malformations. Therefore, histological analysis is recommended. Imaging and pathological analyses should be performed in accordance with the ISSVA classification to minimize inter-observer discrepancies. CRITICAL RELEVANCE STATEMENT: Imaging features of benign vascular tumors on MRI are non-specific, leading to discrepancies with pathological findings and potential overlap with atypical vascular malformations. Imaging and histological analyses should be performed in accordance with ISSVA guidelines to improve patient management. KEY POINTS: The imaging features of benign vascular tumors are non-specific. Histological analysis is recommended for soft tissue vascular tumors in adults. Analyses of soft tissue vascular tumors should be performed in accordance with ISSVA guidelines.

20.
Strahlenther Onkol ; 189(9): 729-37, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23842635

RESUMO

BACKGROUND: A joint analysis of clinical data from centres within the European section of the International Society of Intraoperative Radiation Therapy (ISIORT-Europe) was undertaken in order to define the range of intraoperative radiotherapy (IORT) techniques and indications encompassed by its member institutions. MATERIALS AND METHODS: In 2007, the ISIORT-Europe centres were invited to record demographic, clinical and technical data relating to their IORT procedures in a joint online database. Retrospective data entry was possible. RESULTS: The survey encompassed 21 centres and data from 3754 IORT procedures performed between 1992 and 2011. The average annual number of patients treated per institution was 42, with three centres treating more than 100 patients per year. The most frequent tumour was breast cancer with 2395 cases (63.8 %), followed by rectal cancer (598 cases, 15.9 %), sarcoma (221 cases, 5.9 %), prostate cancer (108 cases, 2.9 %) and pancreatic cancer (80 cases, 2.1 %). Clinical details and IORT technical data from these five tumour types are reported. CONCLUSION: This is the first report on a large cohort of patients treated with IORT in Europe. It gives a picture of patient selection methods and treatment modalities, with emphasis on the main tumour types that are typically treated by this technique and may benefit from it.


Assuntos
Bases de Dados Factuais , Cuidados Intraoperatórios/estatística & dados numéricos , Neoplasias/epidemiologia , Neoplasias/terapia , Seleção de Pacientes , Padrões de Prática Médica/estatística & dados numéricos , Radioterapia Adjuvante/estatística & dados numéricos , Europa (Continente)/epidemiologia , Humanos , Prevalência
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