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1.
J Phys Chem A ; 128(11): 2200-2209, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38445978

RESUMEN

The standard molar enthalpy of formation for trimellitic acid (TMAc) in the crystalline phase at 298.15 K, ΔfHm°(cr), was calculated experimentally from the enthalpy of combustion through combustion calorimetry experiments. Likewise, the standard molar enthalpy of sublimation was determined from the standard molar enthalpy of fusion and from the standard molar enthalpy of vaporization from differential scanning calorimetry and thermogravimetry, respectively. Subsequently, the standard molar enthalpies of formation in the gas-phase at 298.15 K, ΔfHm°(g), were calculated. The enthalpies of formation for TMAc, hemimellitic, and trimesic acids were predicted using multiple linear regression (MLR) with a nonreplacement evaluation technique. MLR was applied to the data set that allowed estimating these thermochemical properties with an R2 greater than 0.99. This model was used to compare the predicted and experimental results for benzene carboxylic acids.

2.
Semin Musculoskelet Radiol ; 28(3): 305-317, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38768595

RESUMEN

The posterolateral corner (PLC) of the knee is a complex anatomical-functional unit that includes ligamentous and tendinous structures that are crucial for joint stability. This review discusses the intricate anatomy, biomechanics, and imaging modalities, as well as the current challenges in diagnosing PLC injuries, with an emphasis on magnetic resonance imaging (MRI). Recognizing the normal MRI anatomy is critical in identifying abnormalities and guiding effective treatment strategies. Identification of the smaller structures of the PLC, traditionally difficult to depict on imaging, may not be necessary to diagnose a clinically significant PLC injury. Injuries to the PLC, often associated with cruciate ligament tears, should be promptly identified because failure to recognize them may result in persistent instability, secondary osteoarthritis, and cruciate graft failure.


Asunto(s)
Traumatismos de la Rodilla , Articulación de la Rodilla , Imagen por Resonancia Magnética , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Traumatismos de la Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Fenómenos Biomecánicos , Ligamentos Articulares/diagnóstico por imagen , Ligamentos Articulares/lesiones , Inestabilidad de la Articulación/diagnóstico por imagen
3.
Z Rheumatol ; 83(4): 303-305, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38175270

RESUMEN

Phalangeal microgeodic syndrome (PMS) is a rare osteolytic disorder of unknown etiology that typically affects children up to 15 years old during colder months. Transient peripheral circulatory impairment probably underlines its pathogenesis. Conservative treatment with eviction of cold exposure is often successful. We report the case of a young woman presenting with joint pain in her feet, along with toe discoloration and redness, where a diagnosis of PMS was established based on magnetic resonance imaging findings and exclusion of other differential diagnostic entities. Pharmacological treatment was deemed necessary for symptomatic relief, but a trial of calcium channel blocker (CCB) was not tolerated by the patient. The patient was then started on pentoxifylline, with significant clinical improvement.


Asunto(s)
Pentoxifilina , Femenino , Humanos , Diagnóstico Diferencial , Pentoxifilina/uso terapéutico , Síndrome , Resultado del Tratamiento
4.
Proc Biol Sci ; 290(1990): 20222203, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36629117

RESUMEN

Abandonment of agricultural lands promotes the global expansion of secondary forests, which are critical for preserving biodiversity and ecosystem functions and services. Such roles largely depend, however, on two essential successional attributes, trajectory and recovery rate, which are expected to depend on landscape-scale forest cover in nonlinear ways. Using a multi-scale approach and a large vegetation dataset (843 plots, 3511 tree species) from 22 secondary forest chronosequences distributed across the Neotropics, we show that successional trajectories of woody plant species richness, stem density and basal area are less predictable in landscapes (4 km radius) with intermediate (40-60%) forest cover than in landscapes with high (greater than 60%) forest cover. This supports theory suggesting that high spatial and environmental heterogeneity in intermediately deforested landscapes can increase the variation of key ecological factors for forest recovery (e.g. seed dispersal and seedling recruitment), increasing the uncertainty of successional trajectories. Regarding the recovery rate, only species richness is positively related to forest cover in relatively small (1 km radius) landscapes. These findings highlight the importance of using a spatially explicit landscape approach in restoration initiatives and suggest that these initiatives can be more effective in more forested landscapes, especially if implemented across spatial extents of 1-4 km radius.


Asunto(s)
Ecosistema , Bosques , Biodiversidad , Árboles , Plantas
5.
Org Biomol Chem ; 21(30): 6096-6102, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37309677

RESUMEN

An unprecedented transition metal free [2,3]-sigmatropic rearrangement involving stabilized sulfur ylides and allenoates has been thoroughly established. The scope and utility of this reaction have been extensively studied resulting in C-C bond formation under mild conditions with greater than 20 examples reported. A highlight of the work is the simple and fully operational process that does not involve the use of carbenes or the associated hazardous and sensitive reagents. The reaction can be performed at room temperature and using an open flask. Interestingly, the new C-C bond formation reaction is gram scalable, and the obtained isomers are readily separable, affording interesting building blocks that can be used in the preparation of complex molecules.

6.
Future Oncol ; 19(40): 2669-2682, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38088163

RESUMEN

NTRK gene fusions have been detected in more than 25 types of tumors and their prevalence is approximately 0.3% in solid tumors. This low prevalence makes identifying patients who could benefit from TRK inhibitors a considerable challenge. Furthermore, while numerous papers on the evaluation of NTRK fusion genes are available, not all countries have guidelines that are suitable for their setting, as is the case with Latin America. Therefore, a group of oncologists and pathologists from several countries in Latin America (Argentina, Chile, Ecuador, Mexico, Peru and Uruguay) met to discuss and reach consensus on how to identify patients with NTRK gene fusions in solid tumors. To do so, they developed a practical algorithm, considering their specific situation and limitations.


Asunto(s)
Neoplasias , Oncólogos , Humanos , Receptor trkA/genética , América Latina , Patólogos , Neoplasias/diagnóstico , Neoplasias/genética , Fusión Génica , Proteínas de Fusión Oncogénica/genética
7.
Mar Drugs ; 21(12)2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38132958

RESUMEN

A mathematical concept, n-tuples are originally applied to medicinal chemistry, especially with the creation of scaffold diversity inspired by the hybridisation of different commercial drugs with cytarabine, a synthetic arabinonucleoside derived from two marine natural products, spongouridine and spongothymidine. The new methodology explores the virtual chemical-factorial combination of different commercial drugs (immunosuppressant, antibiotic, antiemetic, anti-inflammatory, and anticancer) with the anticancer drug cytarabine. Real chemical combinations were designed and synthesised for 8-duples, obtaining a small representative library of interesting organic molecules to be biologically tested as proof of concept. The synthesised library contains classical molecular properties regarding the Lipinski rules and/or beyond rules of five (bRo5) and is represented by the covalent combination of the anticancer drug cytarabine with ibuprofen, flurbiprofen, folic acid, sulfasalazine, ciprofloxacin, bortezomib, and methotrexate. The insertion of specific nomenclature could be implemented into artificial intelligence algorithms in order to enhance the efficiency of drug-hunting programs. The novel methodology has proven useful for the straightforward synthesis of most of the theoretically proposed duples and, in principle, could be extended to any other central drug.


Asunto(s)
Antineoplásicos , Citarabina , Citarabina/farmacología , Inteligencia Artificial , Antineoplásicos/farmacología
8.
Int J Mol Sci ; 24(12)2023 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-37373431

RESUMEN

Defective molybdenum disulfide (MoS2) monolayers (MLs) modified with coinage metal atoms (Cu, Ag and Au) embedded in sulfur vacancies are studied at a dispersion-corrected density functional level. Atmospheric constituents (H2, O2 and N2) and air pollutants (CO and NO), known as secondary greenhouse gases, are adsorbed on up to two atoms embedded into sulfur vacancies in MoS2 MLs. The adsorption energies suggest that the NO (1.44 eV) and CO (1.24 eV) are chemisorbed more strongly than O2 (1.07 eV) and N2 (0.66 eV) on the ML with a cooper atom substituting for a sulfur atom. Therefore, the adsorption of N2 and O2 does not compete with NO or CO adsorption. Besides, NO adsorbed on embedded Cu creates a new level in the band gap. In addition, it was found that the CO molecule could directly react with the pre-adsorbed O2 molecule on a Cu atom, forming the complex OOCO, via the Eley-Rideal reaction mechanism. The adsorption energies of CO, NO and O2 on Au2S2, Cu2S2 and Ag2S2 embedded into two sulfur vacancies were competitive. Charge transference occurs from the defective MoS2 ML to the adsorbed molecules, oxidizing the later ones (NO, CO and O2) since they act as acceptors. The total and projected density of states reveal that a MoS2 ML modified with copper, gold and silver dimers could be used to design electronic or magnetic devices for sensing applications in the adsorption of NO, CO and O2 molecules. Moreover, NO and O2 molecules adsorbed on MoS2-Au2s2 and MoS2-Cu2s2 introduce a transition from metallic to half-metallic behavior for applications in spintronics. These modified monolayers are expected to exhibit chemiresistive behavior, meaning their electrical resistance changes in response to the presence of NO molecules. This property makes them suitable for detecting and measuring NO concentrations. Also, modified materials with half-metal behavior could be beneficial for spintronic devices, particularly those that require spin-polarized currents.


Asunto(s)
Cobre , Gases , Adsorción , Molibdeno , Oro , Azufre
9.
Bull Environ Contam Toxicol ; 110(6): 116, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37318661

RESUMEN

The particle size reduction technology is used in several segments, including sunscreens and new techniques and product improvement. One of the main particles used in the sunscreens formulation is titanium dioxide (TiO2). This formulation allows for better characteristics of these products. Perspectives like incorporation of the particles by other biological systems beyond humans and their effects should be observed. This work aimed to evaluate the titanium dioxide microparticles phytotoxicity on Lactuca sativa L. plants through tests of germination, growth, and weight analysis using microscopy techniques: optical microscopy (OM) and scanning electron microscopy (SEM). Some of the results showed cellular and morphological damage, mainly in the roots and 50 mg L-1 TiO2 concentration, confirmed by SEM. Additionally, anatomical damages like vascular bundle disruption and irregularity in the cortex cells were confirmed by SEM. Additionally, anatomical damages were observed on the three main organs (root, hypocotyl, and leaves) evidenced by the OM. Perspectives to confirm new hypotheses of the interaction of nanomaterials with biological systems are necessary.


Asunto(s)
Lactuca , Plantones , Humanos , Lactuca/metabolismo , Protectores Solares , Germinación , Semillas , Raíces de Plantas
10.
Trop Anim Health Prod ; 55(3): 174, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37099050

RESUMEN

Ovine reproductive behavior depends on annual photoperiodic cycle and its impact on endogenous melatonin secretion. In this regard, exogenous melatonin administration previous to the physiological anestrus period could modify the reproductive performance of sheep in the northwest of Mexico. Two independent studies were performed to evaluate such hypothesis in hair sheep implanted with melatonin prior to the anestrus season in latitudes 24° and 25° of Mexico. Study 1 involved 15 rams assigned to one of three treatments receiving 0mg (n=5), 18mg (n=5), or 36mg (n=5) of melatonin subcutaneously. Study variables were measured monthly since implantation (d0) and included testosterone concentration, scrotal circumference, mass motility, individual motility, and sperm concentration. Study 2 included 50 ewes assigned to one of two treatments receiving 0mg (n=25) or 18mg (n=25) of melatonin subcutaneously. In ewes, progesterone concentration and the frequency of females in anestrus were measured during the implantation (-30d), as well as at the beginning (0d) and at the end (45d) of the mating period, while pregnancy rate was determined by ultrasonography 45d after. Continuous variables were analyzed using a mixed effects model considering treatment, time, and the treatment by time interaction as fixed effects. Animal nested within treatment was the random effect. Binary variables were analyzed using the chi-square test. In males, melatonin improved testosterone and sperm concentrations (P<0.05), while in females, a 28% higher pregnancy rate was observed in implanted ewes (P<0.05). Therefore, melatonin enhanced reproductive parameters in both sexes and its exogenous administration previous to the anestrus season in northwest Mexico could be more effective in rams.


Asunto(s)
Melatonina , Embarazo , Ovinos , Animales , Femenino , Masculino , Anestro , Estaciones del Año , México , Semen , Oveja Doméstica , Testosterona
11.
Mar Drugs ; 20(6)2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35736176

RESUMEN

The bengamides comprise an interesting family of natural products isolated from sponges belonging to the prolific Jaspidae family. Their outstanding antitumor properties, coupled with their unique mechanism of action and unprecedented molecular structures, have prompted an intense research activity directed towards their total syntheses, analogue design, and biological evaluations for their development as new anticancer agents. Together with these biological studies in cancer research, in recent years, the bengamides have been identified as potential antibiotics by their impressive biological activities against various drug-resistant bacteria such as Mycobacterium tuberculosis and Staphylococcus aureus. This review reports on the new advances in the chemistry and biology of the bengamides during the last years, paying special attention to their development as promising new antibiotics. Thus, the evolution of the bengamides from their initial exploration as antitumor agents up to their current status as antibiotics is described in detail, highlighting the manifold value of these marine natural products as valid hits in medicinal chemistry.


Asunto(s)
Antineoplásicos , Productos Biológicos , Mycobacterium tuberculosis , Antibacterianos/química , Antibacterianos/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Productos Biológicos/química , Productos Biológicos/farmacología , Estructura Molecular
12.
Reprod Domest Anim ; 57(8): 839-848, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35434829

RESUMEN

Sustainability of dairy production depends largely on reproductive efficiency that is affected by heat stress due to high ambient temperature and humidity during summer. Supplementation of minerals has been proposed as a management strategy to minimize adverse impact of heat stress on fertility. The objective of this study was to determine the effects of an injectable mineral supplement (Fosfosan) containing selenium (Se), copper (Cu), potassium (K), magnesium (Mg) and phosphorus (P) on the ovarian structures, reproductive hormones and conception rate of heat-stressed Holstein cows. Sixteen cows were assigned during summer to one of two treatments, a control group (CON; n = 8) and a mineral-supplemented group (SUP; n = 8). Ambient temperature and relative humidity records were collected and processed to estimate the temperature-humidity index (THI), which confirmed a heat-stressed environment during the study (avg. THI = 79.4). Cows were subjected to a fixed-time artificial insemination (FTAI) program using the CIDR-Synch synchronization protocol. Traits indicative of ovarian activity were recorded during and after this protocol, as well as serum concentrations of reproductive hormones. Pregnancy diagnosis was made 28 and 35 d after FTAI. A completely randomized block design with repeated measures over time was performed to study ovarian functional structures and its hormonal profiles. Correlations and regressions were estimated to study relationships between ovarian structures and related hormones. Mineral supplementation did not increase follicular diameter or follicular populations (p > .05), yet tended to increase corpus luteum diameter (p < .10), and it enhanced (p < .01) oestrogen and progesterone serum concentrations and improved (p < .05) cow's conception rate. Diameter of dominant follicles and corpus luteum was correlated (p < .05) with oestrogen and progesterone levels, respectively, but only in mineral-treated cows. Two additional dairy herds were evaluated to confirm that mineral supplementation improved conception rate during the heat stress period (objective 2). Cows from dairy 1 received FTAI during winter (n = 401) and summer (n = 240), whereas cows from dairy 2 were bred after natural detected oestrus during winter (n = 558) and summer (n = 314). Conception rates were higher (p < .05) in winter than summer and they improved (p < .05) with mineral supplementation, but only in cows managed during summer. In conclusion, supplementation of minerals enhanced hormonal secretion from ovarian structures and improved conception rate in Holstein cows exposed to summer heat stress.


Asunto(s)
Enfermedades de los Bovinos , Trastornos de Estrés por Calor , Animales , Bovinos , Suplementos Dietéticos , Estrógenos/farmacología , Sincronización del Estro , Femenino , Trastornos de Estrés por Calor/veterinaria , Inseminación Artificial/veterinaria , Lactancia , Embarazo , Progesterona , Reproducción
13.
Sensors (Basel) ; 22(18)2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36146075

RESUMEN

Network slicing is a vital component of the 5G system to support diverse network scenarios, creating virtual networks (slices) by mapping virtual network requests to real networks. The mapping is an arduous computing process, mathematically studied and known as the Virtual Network Embedding (VNE) problem, and its complexity is NP-Hard. The mapping process is oriented to respect the QoS demands from the virtual network requests and the available resources in the physical-substrate infrastructure. Meta-heuristic approaches are a suitable way to solve the VNE problems because of their capacity to escape from the local optimum and adapt the solution search to complex networks; these abilities are essential in 5G networks scenarios. This article presents a systematic review of meta-heuristics organized by application, development and problem-solving approaches to VNE. It also provides the standard parameters to model the infrastructure and virtual network requests to simulate network slicing as a service. Finally, our work proposes some future research based on the discovered gaps.


Asunto(s)
Algoritmos , Heurística , Solución de Problemas
14.
Int J Mol Sci ; 23(6)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35328550

RESUMEN

The corrosion inhibition of 5-O-ß-D-glucopyranosyl-7-methoxy-3',4'-dihydroxy-4-phenylcoumarin (4-PC) in AISI 1018 steel immersed in 3% NaCl + CO2 was studied by electrochemical impedance spectroscopy (EIS). The results showed that, at just 10 ppm, 4-PC exerted protection against corrosion with Õ² = 90% and 97% at 100 rpm. At static conditions, the polarization curves indicated that, at 5 ppm, the inhibitor presented anodic behavior, while at 10 and 50 ppm, there was a cathodic-type inhibitor. The inhibitor adsorption was demonstrated to be chemisorption, according to the Langmuir isotherm for 100 and 500 rpm. By means of SEM-EDS, the corrosion inhibition was demonstrated, as well as the fact that the organic compound was effective for up to 72 h of immersion. At static conditions, dispersion-corrected density functional theory results reveal that the chemical bonds established by the phenyl group of 4-PC are responsible of the chemisorption on the steel surface. According with Fukui reactivity indices, the molecules adsorbed on the metal surface provide a protective cover against nucleophilic and electrophilic attacks, pointing to the corrosion inhibition properties of 4-PC.


Asunto(s)
Cloruro de Sodio , Acero , Dióxido de Carbono , Corrosión , Cumarinas , Glucósidos , Modelos Teóricos , Cloruro de Sodio/química , Cloruro de Sodio/farmacología , Acero/química
15.
Trop Anim Health Prod ; 54(2): 88, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-35124730

RESUMEN

The lactation curve in dairy cows is influenced by the calving season, which is highly dependent on the warm climate in semi-arid regions. Objective herein was to evaluate effects of calving season on the parameters and components of the lactation curve in Holstein cows. The study included 278,317 milk records collected from 1086 cows from the 1st to 5th calving and good body condition score. The cows were grouped according to the season in which they calved: winter-calved (CS1), summer-calved (CS2), and autumn-calved cows (CS3). Ambient temperature and humidity data were used to calculate the temperature-humidity index (THI). The NLIN procedure was used to estimate the parameters of the lactation curve that served to calculate the components. The mixed procedure was executed to analyze the fixed effect of calving season. Associations between lactation curve traits were tested using correlation and regression analyses. A univariate model was utilized to calculate heritability. Average THI values during the lactation period were 73.5, 68.5, and 69.5 units for CS1, CS2, and CS3 groups, respectively. Initial milk production and increasing rate to the maximum milk yield in CS1 and CS3 groups were higher (P < 0.05) than CS2 cows. However, persistency and total milk yield during the entire lactation period were superior (P < 0.05) for CS2 and CS3 cows compared to CS1 cows, probably due to the moderate heat stress during the lactation period in the CS1 group. In cows from CS2 and CS3 groups, total milk production at 305 days was moderately correlated with initial milk production (r = 0.47; P < 0.05), and highly correlated with milk yield at peak day (r = 0.91; P < 0.05) which resulted as reliable predictor for total milk yield during the entire lactation (R2 = 0.83). In conclusion, the THI prevailing during the different calving seasons appeared to be an important factor influencing the performance of the lactation curve.


Asunto(s)
Clima Desértico , Lactancia , Animales , Bovinos , Femenino , Humedad , Leche , Estaciones del Año
16.
PLoS Pathog ; 15(10): e1008117, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31644574

RESUMEN

The resolution of the three-dimensional structure of infectious prions at the atomic level is pivotal to understand the pathobiology of Transmissible Spongiform Encephalopathies (TSE), but has been long hindered due to certain particularities of these proteinaceous pathogens. Difficulties related to their purification from brain homogenates of disease-affected animals were resolved almost a decade ago by the development of in vitro recombinant prion propagation systems giving rise to highly infectious recombinant prions. However, lack of knowledge about the molecular mechanisms of the misfolding event and the complexity of systems such as the Protein Misfolding Cyclic Amplification (PMCA), have limited generating the large amounts of homogeneous recombinant prion preparations required for high-resolution techniques such as solid state Nuclear Magnetic Resonance (ssNMR) imaging. Herein, we present a novel recombinant prion propagation system based on PMCA that substitutes sonication with shaking thereby allowing the production of unprecedented amounts of multi-labeled, infectious recombinant prions. The use of specific cofactors, such as dextran sulfate, limit the structural heterogeneity of the in vitro propagated prions and makes possible, for the first time, the generation of infectious and likely homogeneous samples in sufficient quantities for studies with high-resolution structural techniques as demonstrated by the preliminary ssNMR spectrum presented here. Overall, we consider that this new method named Protein Misfolding Shaking Amplification (PMSA), opens new avenues to finally elucidate the three-dimensional structure of infectious prions.


Asunto(s)
Resonancia Magnética Nuclear Biomolecular/métodos , Proteínas Priónicas/metabolismo , Priones/metabolismo , Animales , Arvicolinae , Sistema Nervioso Central/patología , Sulfato de Dextran/farmacología , Modelos Animales de Enfermedad , Ratones Transgénicos , Enfermedades por Prión/patología , Estructura Terciaria de Proteína , Deficiencias en la Proteostasis/patología
17.
FASEB J ; 34(3): 3969-3982, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31944411

RESUMEN

Unlike other species, prion disease has never been described in dogs even though they were similarly exposed to the bovine spongiform encephalopathy (BSE) agent. This resistance prompted a thorough analysis of the canine PRNP gene and the presence of a negatively charged amino acid residue in position 163 was readily identified as potentially fundamental as it differed from all known susceptible species. In the present study, the first transgenic mouse model expressing dog prion protein (PrP) was generated and challenged intracerebrally with a panel of prion isolates, none of which could infect them. The brains of these mice were subjected to in vitro prion amplification and failed to find even minimal amounts of misfolded prions providing definitive experimental evidence that dogs are resistant to prion disease. Subsequently, a second transgenic model was generated in which aspartic acid in position 163 was substituted for asparagine (the most common in prion susceptible species) resulting in susceptibility to BSE-derived isolates. These findings strongly support the hypothesis that the amino acid residue at position 163 of canine cellular prion protein (PrPC ) is a major determinant of the exceptional resistance of the canidae family to prion infection and establish this as a promising therapeutic target for prion diseases.


Asunto(s)
Ácido Aspártico/química , Ácido Glutámico/química , Priones/química , Priones/patogenicidad , Animales , Bioensayo , Encéfalo/patología , Perros , Ratones , ATPasas Transportadoras de Calcio de la Membrana Plasmática/metabolismo
18.
Catheter Cardiovasc Interv ; 97(6): E893-E896, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33211370

RESUMEN

Valve-in-valve (ViV) procedures have emerged from an off-label procedure to a safe and efficient alternative to redo aortic valve replacement in the treatment of symptomatic structural valve deterioration (SVD). During ViV procedures, optimal placement of the transcatheter heart valve (THV) inside the degenerated bioprosthesis is of paramount importance regarding complications such as device embolization, coronary obstruction, periprosthetic regurgitation, residual gradients, and mitral valve injury, but also for the attainment of optimal hemodynamics. In the case of the Mosaic (Medtronic, Minneapolis, MN) valve, the limited radiopaque landmarks represent a challenge to a reproducible, optimal implantation. Such implantation may require multiple contrast injections and transesophageal echocardiogram (TEE) guidance. We herein describe a computer-assisted ViV procedure inside a deteriorated Mosaic valve, achieving reproducible optimal placement using a preacquired library of bioprostheses 3D models. Our approach suggests an evolving paradigm in ViV procedures, from safe and efficient toward optimal therapy for symptomatic SVD.


Asunto(s)
Bioprótesis , Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Humanos , Diseño de Prótesis , Falla de Prótesis , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del Tratamiento
19.
Eur Radiol ; 31(7): 4634-4651, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33411052

RESUMEN

OBJECTIVES: Imaging assessment for the clinical management of femoroacetabular impingement (FAI) is controversial because of a paucity of evidence-based guidance and notable variability among practitioners. Hence, expert consensus is needed because standardised imaging assessment is critical for clinical practice and research. We aimed to establish expert-based statements on FAI imaging by using formal methods of consensus building. METHODS: The Delphi method was used to formally derive consensus among 30 panel members from 13 countries. Forty-four questions were agreed upon, and relevant seminal literature was circulated and classified in major topics to produce answering statements. The level of evidence was noted for all statements, and panel members were asked to score their level of agreement (0-10). This is the second part of a three-part consensus series and focuses on 'General issues' and 'Parameters and reporting'. RESULTS: Forty-seven statements were generated and group consensus was reached for 45. Twenty-five statements pertaining to 'General issues' (9 addressing diagnosis, differential diagnosis, and postoperative imaging) and 'Parameters and reporting' (16 addressing femoral/acetabular parameters) were produced. CONCLUSIONS: The available evidence was reviewed critically, recommended criteria for diagnostic imaging highlighted, and the roles/values of different imaging parameters assessed. Radiographic evaluation (AP pelvis and a Dunn 45° view) is the cornerstone of hip-imaging assessment and the minimum imaging study that should be performed when evaluating adult patients for FAI. In most cases, cross-sectional imaging is warranted because MRI is the 'gold standard' imaging modality for the comprehensive evaluation, differential diagnosis assessment, and FAI surgical planning. KEY POINTS: • Diagnostic imaging for FAI is not standardised due to scarce evidence-based guidance on which imaging modalities and diagnostic criteria/parameters should be used. • Radiographic evaluation is the cornerstone of hip assessment and the minimum study that should be performed when assessing suspected FAI. Cross-sectional imaging is justified in most cases because MRI is the 'gold standard' modality for comprehensive FAI evaluation. • For acetabular morphology, coverage (Wiberg's angle and acetabular index) and version (crossover, posterior wall, and ischial spine signs) should be assessed routinely. On the femoral side, the head-neck junction morphology (α° and offset), neck morphology (NSA), and torsion should be assessed.


Asunto(s)
Pinzamiento Femoroacetabular , Acetábulo , Adulto , Pinzamiento Femoroacetabular/diagnóstico por imagen , Fémur , Articulación de la Cadera/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética
20.
Eur Radiol ; 31(7): 4652-4668, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33411053

RESUMEN

OBJECTIVES: Imaging diagnosis of femoroacetabular impingement (FAI) remains controversial due to a lack of high-level evidence, leading to significant variability in patient management. Optimizing protocols and technical details is essential in FAI imaging, although challenging in clinical practice. The purpose of this agreement is to establish expert-based statements on FAI imaging, using formal consensus techniques driven by relevant literature review. Recommendations on the selection and use of imaging techniques for FAI assessment, as well as guidance on relevant radiographic and MRI classifications, are provided. METHODS: The Delphi method was used to assess agreement and derive consensus among 30 panel members (musculoskeletal radiologists and orthopedic surgeons). Forty-four questions were agreed on and classified into five major topics and recent relevant literature was circulated, in order to produce answering statements. The level of evidence was assessed for all statements and panel members scored their level of agreement with each statement during 4 Delphi rounds. Either "group consensus," "group agreement," or "no agreement" was achieved. RESULTS: Forty-seven statements were generated and group consensus was reached for 45. Twenty-two statements pertaining to "Imaging techniques" were generated. Eight statements on "Radiographic assessment" and 12 statements on "MRI evaluation" gained consensus. No agreement was reached for the 2 "Ultrasound" related statements. CONCLUSION: The first international consensus on FAI imaging was developed. Researchers and clinicians working with FAI and hip-related pain may use these recommendations to guide, develop, and implement comprehensive, evidence-based imaging protocols and classifications. KEY POINTS: • Radiographic evaluation is recommended for the initial assessment of FAI, while MRI with a dedicated protocol is the gold standard imaging technique for the comprehensive evaluation of this condition. • The MRI protocol for FAI evaluation should include unilateral small FOV with radial imaging, femoral torsion assessment, and a fluid sensitive sequence covering the whole pelvis. • The definite role of other imaging methods in FAI, such as ultrasound or CT, is still not well defined.


Asunto(s)
Pinzamiento Femoroacetabular , Consenso , Pinzamiento Femoroacetabular/diagnóstico por imagen , Cadera , Articulación de la Cadera/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética
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