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1.
IEEE Trans Med Imaging ; 43(3): 1247-1258, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37971921

RESUMO

Assessing the critical view of safety in laparoscopic cholecystectomy requires accurate identification and localization of key anatomical structures, reasoning about their geometric relationships to one another, and determining the quality of their exposure. Prior works have approached this task by including semantic segmentation as an intermediate step, using predicted segmentation masks to then predict the CVS. While these methods are effective, they rely on extremely expensive ground-truth segmentation annotations and tend to fail when the predicted segmentation is incorrect, limiting generalization. In this work, we propose a method for CVS prediction wherein we first represent a surgical image using a disentangled latent scene graph, then process this representation using a graph neural network. Our graph representations explicitly encode semantic information - object location, class information, geometric relations - to improve anatomy-driven reasoning, as well as visual features to retain differentiability and thereby provide robustness to semantic errors. Finally, to address annotation cost, we propose to train our method using only bounding box annotations, incorporating an auxiliary image reconstruction objective to learn fine-grained object boundaries. We show that our method not only outperforms several baseline methods when trained with bounding box annotations, but also scales effectively when trained with segmentation masks, maintaining state-of-the-art performance.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Semântica
2.
Biomolecules ; 12(10)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36291555

RESUMO

Human alpha 1 antitrypsin (hAAT) is a multifunctional protein that has been shown to have anti-inflammatory and cellular protective properties. While previous studies demonstrated the antiaging potential of hAAT, the mechanism(s) underlying the antiaging effect remain elusive. In this study, we performed a detailed analysis of transcriptomic data that indicated that NF-κB-targeted genes and NF-κB-regulated pathways were selectively inhibited by hAAT treatment. We further showed that the first detectable impact of hAAT treatment was the inhibition of the nuclear activity of NF-κB. Subsequently, hAAT treatment suppressed the mRNA levels of NF-κB-targeted genes, as well as NF-κB itself (P65 and P50), in human senescent cells. Using Drosophila models, we further examined the impact of hAAT on locomotor activity and endurance. Finally, using an adult-specific promotor, we demonstrated that overexpression of hAAT in the late stage of life significantly extended the lifespan of transgenic flies. These results extend the current understanding of the anti-inflammatory function of hAAT.


Assuntos
Longevidade , alfa 1-Antitripsina , Animais , Humanos , alfa 1-Antitripsina/metabolismo , Longevidade/genética , NF-kappa B/genética , Drosophila/metabolismo , RNA Mensageiro
3.
Orthod Fr ; 93(4): 309-314, 2022 12 01.
Artigo em Francês | MEDLINE | ID: mdl-36718752

RESUMO

Introduction: The prognostic improvement for dental auto-transplants is the result of a better understanding in the physiopathology of the periodontium and also of the refining of the technical operative procedure. This fact allows the use of third molars as donor site for the replacement of absent, or first or second badly decayed molars. Discussion: This possible therapy is a supplement argument for the conservation of third molars and their extraction must be indicated only when the anatomic situation presents a pathological risk. Results: If, in adults, it is possible to compare the advantages and disadvantages with the classical implant or prosthetic techniques, it should however be considered as first choice therapy for adolescents and young adults. Indeed, in these cases, the lower risk of root ankylosis avoids passive intrusion and the osteogenic effect of the desmodontium allows normal alveolar bone formation.


Introduction: L'amélioration du pronostic des autogreffes dentaires, envisageable par une meilleure compréhension de la physiopathologie du parodonte et par un affinement de la technique opératoire qui en résulte, permet d'utiliser à bon compte les dents de sagesse comme site donneur dans le remplacement de molaires absentes ou trop fortement délabrées. Discussion: Cette possibilité thérapeutique est un argument supplémentaire à la conservation des dents de sagesse dont l'extraction ne devrait être indiquée que lorsque la situation anatomique de ces dents présente un risque pathologique. Résultats: Si, chez l'adulte, il est possible d'en discuter les avantages et les inconvénients avec les techniques prothétiques et implantaires classiques, les autogreffes dentaires doivent en revanche être considérées comme la solution de choix chez l'adolescent ou le jeune adulte. En effet, dans ces cas, le risque moindre d'ankylose radiculaire évite l'ingression passive de la dent remplacée et l'action ostéogénique de son desmodonte permet une formation normale de l'os alvéolaire qui l'environne.


Assuntos
Dente Serotino , Reabsorção da Raiz , Anquilose Dental , Adolescente , Humanos , Adulto Jovem , Dente Molar/cirurgia , Dente Molar/patologia , Dente Serotino/patologia , Dente Serotino/transplante , Prognóstico , Reabsorção da Raiz/patologia , Extração Dentária
4.
Chemistry ; 27(51): 12965-12970, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34278628

RESUMO

A chemistry platform for the fast continuous synthesis of III-V quantum dots is demonstrated. III-nitride QDs are prepared by using short residence times (less than 30 s) in a one-step continuous process with supercritical solvents. GaN QDs prepared via this route exhibit strong UV photoluminescence with a structuring of the emission signal at low temperature (5 K), confirming their high quality. An example of metal site substitution is given with the synthesis of Inx Ga1-x N solid solution. A continuous bandgap shift towards lower energies is demonstrated when increasing the indium content with strong photoluminescence signals from UV to visible. The chemistry platform proposed could be easily extrapolated to binary and ternary III phosphides or arsenides with the homologous V source.

5.
Surg Innov ; 28(2): 202-207, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34128747

RESUMO

We submit a summary of some of the activities of the IHU-Strasbourg during the initial period of the COVID-19 pandemic. These were presented as part of the coronnavation effort coordinated by Dr Adrian Park. Three initiatives are presented as follows: Protect-Est App, healthcare worker stress, and converted diving mask for ventilation. Two of the 3 projects are still ongoing, and one (Predoict-Est) has been adopted nationally.


Assuntos
COVID-19/prevenção & controle , Cirurgia Assistida por Computador , Procedimentos Cirúrgicos Operatórios , Engenharia Biomédica , Equipamentos e Provisões Hospitalares , França , Disparidades em Assistência à Saúde , Humanos , Invenções , Pandemias , SARS-CoV-2
6.
Rev. medica electron ; 42(6): 2659-2673, nov.-dic. 2020.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1150045

RESUMO

RESUMEN El gran desarrollo del programa materno infantil en Cuba y la gran atención que a este se brinda hace que muchos médicos limitan a la embarazada al reposo y todavía hay muchas mujeres que se enfrentan al parto sin un entrenamiento previo. Por la importancia de este tema en materia de salud materno infantil se realizó esta revisión bibliográfica con el propósito de aumentar el nivel de conocimientos de los profesionales sobre los beneficios de la misma y lograr un trabajo en equipo del personal que integre el programa, para de esta manera, conseguir el máximo beneficio para las madres, bebés y sus familias. Está demostrado que le hace bien a la mujer embarazada y al bebé. Una gestante preparada es una gestante colaboradora. Por tanto, el entrenamiento junto a hábitos sanos de vida conllevara a que la embarazada tenga un parto en las mejores condiciones físicas y psíquicas, para de esta forma lograr un hijo sano, fuerte y una gran gratificación para toda la familia. La participación activa del padre conseguirá mayor armonía familiar (AU).


SUMMARY The great development of the maternal-infantile program in Cuba and the great attention provided to this, leads to the limitation of pregnant women to rest by doctors, and there are still many women facing the childbirth without a previous training. Due to the importance of this topic in the matter of maternal-infantile health, the authors carried out the current bibliographical review with the purpose of increasing the level of the professionals' knowledge about its benefits and of achieving a team work of the staff integrating the program, and that way, to get the maximum benefit for mothers, babies and their families. It is proved that it makes well to pregnant woman and to the baby. A trained pregnant woman is a collaborative pregnant woman. Therefore, training together with healthy life habits leads pregnant women to childbirth in the better physical and health conditions, delivering this way a healthy, strong child and achieving a great gratification for the whole family. The father's active participation will get bigger family harmony (AU).


Assuntos
Humanos , Feminino , Técnicas Psicológicas/normas , Obstetrícia/métodos , Cuidado Pré-Natal/métodos , Cuidado Pré-Natal/psicologia , Unidade Hospitalar de Ginecologia e Obstetrícia , Família/psicologia , Gestantes/psicologia
8.
Vet Sci ; 7(2)2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32375384

RESUMO

The Region Lagunera, a region in northeast Mexico, is undergoing significant problems with the quality of its groundwater, which exceeds the permissible limits of contaminants and/or heavy metals stipulated in Mexican legislation. The present study evaluated chronic toxicity in male goats exposed to arsenic via one ex situ Group 1 (n = 5) and one in situ female goats Group 3 (n = 10). The treatment in Group 1 was carried out in the La Laguna experimental field of the Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP), located in Matamoros, Coahuila, Mexico. Sodium arsenite (2 mg/kg) was orally administered for 84 days to five male Creole goats, aged between four and five years old and weighing between 60 and 70 kg, in order to determine its effect on urine toxicity, libido, and physiological condition, an untreated group (n = 5) was included (Group 2). The experiment in group 3 was conducted on ten female Creole goats, aged between four and six years old and weighing between 40 and 49 kg, in both the contaminated sampling area in the rural community of El Venado and the control sampling area in the rural community of Nuevo Reynosa (Group 4 (n = 5)), in which the arsenic levels were measured in the urine of the exposed goats, as was their physiological condition. Significant differences (p < 0.01) between the groups were found in both the arsenic concentration in the urine and the physiological condition observed in both experimental groups.

9.
Inorg Chem ; 57(8): 4328-4339, 2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-29620359

RESUMO

Luminescent materials based on copper complexes are currently receiving increasing attention because of their rich photophysical properties, opening a wide field of applications. The copper iodide clusters formulated [Cu4I4L4] (L = ligand), are particularly relevant for the development of multifunctional materials based on their luminescence stimuli-responsive properties. In this context, controlling and modulating their photophysical properties is crucial and this can only be achieved by thorough understanding of the origin of the optical properties. We thus report here, the comparative study of a series of cubane copper iodide clusters coordinated by different phosphine ligands, with the goal of analyzing the effect of the ligands nature on the photoluminescence properties. The synthesis, structural, and photophysical characterizations along with theoretical investigations of copper iodide clusters with ligands presenting different electronic properties, are described. A method to simplify the analysis of the 31P solid-state NMR spectra is also reported. While clusters with electron-donating groups present classical luminescence properties, the cluster bearing strong electron-withdrawing substituents exhibits original behavior demonstrating a clear influence of the ligands properties. In particular, the electron-withdrawing character induces a decrease in energy of the unoccupied molecular orbitals, that consequently impacts the emission properties. The modification of the luminescence thermochromic properties of the clusters are supported by density functional theory (DFT) calculations. This study demonstrates that the control of the luminescence properties of these compounds can be achieved through modification of the coordinated ligands, nevertheless the role of the crystal packing should not be underestimated.

10.
Inorg Chem ; 56(20): 12379-12388, 2017 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-28949130

RESUMO

Luminescent mechanochromic materials exhibiting reversible changes of their emissive properties in response to external mechanical forces are currently emerging as an important class of stimuli-responsive materials because of promising technological applications. Here, we report on the luminescence mechanochromic properties of a [Cu4I4(PPh3)4] copper iodide cluster presenting a chair geometry, being an isomer of the most common cubane form. This molecular cluster formulated [Cu4I4(PPh3)4]·2CHCl3 (1) exhibits a highly contrasted emission response to manual grinding, and, interestingly, the optical properties of the ground phase present striking similarities with those of the cubane isomer. In order to understand the underlying mechanism, a comparison with two related compounds has been conducted. The first one is a pseudopolymorph of 1 formulated as [Cu4I4(PPh3)4]·CH2Cl2 (2), which exhibits luminescent mechanochromic properties as well. The other one is also a chair compound but with a slightly different phosphine ligand, namely, [Cu4I4(PPh2C6H4CO2H)4] (3), lacking mechanochromic properties. Structural and optical characterizations of the clusters have been analyzed in light of previous electronic structure calculations. The results suggest an unpreceded mechanochromism phenomenon based on a solid-state chair → cubane isomer conversion. This study shows that polynuclear copper iodide compounds are particularly relevant for the development of luminescent mechanochromic materials.

11.
Inorg Chem ; 54(9): 4483-94, 2015 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-25857746

RESUMO

An original copper(I) iodide cluster of novel geometry obtained by using a diphosphine ligand is reported and is formulated [Cu6I6(PPh2(CH2)3PPh2)3] (1). Interestingly, this sort of "eared cubane" cluster based on the [Cu6I6] inorganic core can be viewed as a combination of the two known [Cu4I4] units, namely, the cubane and the open-chair isomeric geometries. The synthesis, structural and photophysical characterisations, as well as theoretical study of this copper iodide along with the derived cubane (3) and open-chair (2) [Cu4I4(PPh3)4] forms, were investigated. A new polymorph of the cubane [Cu4I4(PPh3)4] cluster is indeed presented (3). The structural differences of the clusters were analyzed by solid-state nuclear magnetic resonance spectroscopy. Luminescence properties of the three clusters were studied in detail as a function of the temperature showing reversible luminescence thermochromism for 1 with an intense orange emission at room temperature. This behavior presents different feature compared to the cubane cluster and completely contrasts with the open isomer, which is almost nonemissive at room temperature. Indeed, the thermochromism of 1 differs by a concomitant increase of the two emission bands by lowering the temperature, in contrast to an equilibrium phenomenon for 3. The luminescence properties of 2 are very different by exhibiting only one single band when cooled. To rationalize the different optical properties observed, density functional theory calculations were performed for the three clusters giving straightforward explanation for the different luminescence thermochromism observed, which is attributed to different contributions of the ligands to the molecular orbitals. Comparison of 3 with its [Cu4I4(PPh3)4] cubane polymorphs highlights the sensibility of the emission properties to the cuprophilic interactions.


Assuntos
Cobre/química , Iodetos/química , Compostos Organometálicos/síntese química , Fosfinas/química , Cristalografia por Raios X , Ligantes , Luminescência , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Teoria Quântica , Temperatura , Termodinâmica
12.
Chemistry ; 21(15): 5892-7, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25755012

RESUMO

Luminescent mechanochromic materials are particularly appealing for the development of stimuli-responsive materials. Establishing the mechanism responsible for the mechanochromism is always an issue owing to the difficulty in characterizing the ground phase. Herein, the study of real crystalline polymorphs of a mechanochromic and thermochromic luminescent copper iodide cluster permits us to clearly establish the mechanism involved. The local disruption of the crystal packing induces changes in the cluster geometry and in particular the modification of the cuprophilic interactions, which consequently modify the emissive states. This study constitutes a step further toward the understanding of the mechanism involved in the mechanochromic luminescent properties of multimetallic coordination complexes.

13.
Chemistry ; 21(13): 5242-51, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25677809

RESUMO

Ce-doped Rb2 KInF6 elpasolite has the potential for tunable luminescence due to an unusual reversible redox process between the cerium and indium cations. Coupled with a deep understanding of the luminescence properties, XRD analysis and DFT calculations are used to locate the doping elements in the host lattice. The origin explanation of the charge-transfer mechanism that causes a decrease or increase in the blue-green cerium emission in opposition to the red indium emission is discussed regarding the crystallographic structure, the connection of the metallic cations and their equilibrium valence. Still detectable after nineteen years, the optical contrast created under irradiation makes this material a good candidate as photosensor for data storage.

14.
J Am Chem Soc ; 136(32): 11311-20, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25076411

RESUMO

An in-depth study of mechanochromic and thermochromic luminescent copper iodide clusters exhibiting structural polymorphism is reported and gives new insights into the origin of the mechanochromic luminescence properties. The two different crystalline polymorphs exhibit distinct luminescence properties with one being green emissive and the other one being yellow emissive. Upon mechanical grinding, only one of the polymorphs exhibits great modification of its emission from green to yellow. Interestingly, the photophysical properties of the resulting partially amorphous crushed compound are closed to those of the other yellow polymorph. Comparative structural and optical analyses of the different phases including a solution of clusters permit us to establish a correlation between the Cu-Cu bond distances and the luminescence properties. In addition, the local structure of the [Cu4I4P4] cluster cores has been probed by (31)P and (65)Cu solid-state NMR analysis, which readily indicates that the grinding process modifies the phosphorus and copper atoms environments. The mechanochromic phenomenon is thus explained by the disruption of the crystal packing within intermolecular interactions inducing shortening of the Cu-Cu bond distances in the [Cu4I4] cluster core and eventually modification of the emissive state. These results definitely establish the role of cuprophilic interactions in the mechanochromism of copper iodide clusters. More generally, this study constitutes a step further into the understanding of the mechanism involved in the mechanochromic luminescent properties of metal-based compounds.

15.
Int Orthod ; 11(4): 422-31, 2013 Dec.
Artigo em Inglês, Francês | MEDLINE | ID: mdl-24176628

RESUMO

Ankylosis is generally discovered following resistance to orthodontic displacement of an impacted canine. This retrospective study, drawing on direct perioperative observation of impacted teeth and of their sites, is intended, among other things, to analyze the causes of resistance to orthodontic movement and to report on the therapeutic interest of the surgical tooth displacement technique in this type of clinical situation. We demonstrate that primary coronal ankylosis can be detected by the orthodontic practitioner using radiographic records, that cervical ankylosis consequent to operative trauma during release is necessarily unpredictable and that it should be suspected when the tooth resists traction for more than 3 months in the absence of any other obvious cause of resistance. Hence, the risk of ankylosis linked to the level of surgical difficulty increases with the depth of coronal submergence within the bone. Moreover, the immediate placement of traction following release reduces the risk of ankylosis. In addition, temporarily suspending traction is a risk factor for secondary apical ankylosis. Finally, surgical positioning should be borne in mind as the final effective option when faced with any form of dental retention.


Assuntos
Dente Canino/cirurgia , Anquilose Dental/diagnóstico , Dente Impactado/cirurgia , Fatores Etários , Humanos , Extrusão Ortodôntica/métodos , Estudos Retrospectivos , Estresse Mecânico , Anquilose Dental/classificação , Anquilose Dental/prevenção & controle , Ápice Dentário/patologia , Colo do Dente/patologia , Coroa do Dente/patologia , Adulto Jovem
18.
Inorg Chem ; 51(2): 794-8, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22221168

RESUMO

A copper iodide cluster bearing reactive silanol groups exhibits thermochromic luminescence properties sensitive to its chemical environment and is thus a suitable building block for the synthesis of optically active materials.

19.
Inorg Chem ; 50(21): 10682-92, 2011 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-21957984

RESUMO

Three copper(I) iodide clusters coordinated by different phosphine ligands formulated [Cu(4)I(4)(PPh(3))(4)] (1), [Cu(4)I(4)(Pcpent(3))(4)] (2), and [Cu(4)I(4)(PPh(2)Pr)(4)] (3) (PPh(3) = triphenylphosphine, Pcpent(3) = tricyclopentylphosphine, and PPh(2)Pr = diphenylpropylphosphine) have been synthesized and characterized by (1)H and (31)P NMR, elemental analysis and single crystal X-ray diffraction analysis. They crystallize in different space groups, namely, monoclinic P21/c, cubic Pa ̅3, and tetragonal I ̅42m for 1, 2, and 3, respectively. The photoluminescence properties of clusters 1 and 3 show reversible luminescence thermochromism with two highly intense emission bands whose intensities are temperature dependent. In accordance to Density Functional Theory (DFT) calculations, these two emission bands have been attributed to two different transitions, a cluster centered (CC) one and a mixed XMCT/XLCT one. Cluster 2 does not exhibit luminescence variation in temperature because of the lack of the latter transition. The absorption spectra of the three clusters have been also rationalized by time dependent DFT (TDDFT) calculations. A simplified model is suggested to represent the luminescence thermochromism attributed to the two different excited states in thermal equilibrium. In contrast with the pyridine derivatives, similar excitation profiles and low activation energy for these phosphine-based clusters reflect high coupling of the two emissive states. The effect of the Cu-Cu interactions on the emission properties of these clusters is also discussed. Especially, cluster 3 with long Cu-Cu contacts exhibits a controlled thermochromic luminescence which is to our knowledge, unknown for this family of copper iodide clusters. These phosphine-based clusters appear particularly interesting for the synthesis of original emissive materials.

20.
Chemphyschem ; 12(7): 1288-93, 2011 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-21506236

RESUMO

Synthesized powders and grown single crystals of nominal compositions Li(6)Ln(BO(3))(3):Yb(3+) (Ln=Y, Gd) were investigated by means of powder and single-crystal X-ray diffraction (XRD), as well as optical near-IR spectroscopy in conjunction with electron paramagnetic resonance (EPR) spectroscopy. The appearance of two distinct zero-phonon lines suggests the existence of two kinds of Yb(3+) ions in the single crystals. The XRD results exclude the possibility of a phase transition occurring between room and low temperatures. EPR spectra of single crystals show the presence of both isolated ions and pairs of ytterbium ions substituted for Y(3+). A strong temperature dependence of the intensity of Yb-Yb pairs resonance lines coincides with temperature dependence of emission peak at 978 nm, confirming a common origin of the defect giving rise to these spectra. Calculated from EPR spectra, the distance between pairs of Yb(3+) is in good agreement with crystallographic ones: R=3.856 Å, R(cryst) =3.849 Å.

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