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1.
Materials (Basel) ; 17(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38998250

RESUMEN

Water pollution is a major environmental challenge. Due to the inefficiency of conventional wastewater treatment plants in degrading many organic complex compounds, these recalcitrant pollutants end up in rivers, lakes, oceans and other bodies of water, affecting the environment and human health. Semiconductor photocatalysis is considered an efficient complement to conventional methods, and the use of various nanomaterials for this purpose has been widely explored, with a particular focus on improving their activity under visible light. This work focuses on developing magnetic and photoactive zinc/magnesium mixed ferrites (Zn0.5Mg0.5Fe2O4) by sol-gel and solvothermal synthesis methods, which are two of the most important and efficient methods used for the synthesis of ferrite nanoparticles. The nanoparticles (NPs) synthesized by the sol-gel method exhibited an average size of 14.7 nm, while those synthesized by the solvothermal method had an average size of 17.4 nm. Both types possessed a predominantly cubic structure and demonstrated superparamagnetic behavior, reaching a magnetization saturation value of 60.2 emu g-1. Due to the high recombination rate of electrons/holes, which is an intrinsic feature of ferrites, surface functionalization with silver was carried out to enhance charge separation. The results demonstrated a strong influence of adsorption and of the deposition of silver. Several optimization steps were performed during synthesis, allowing us to create efficient catalysts, as proved by the almost full removal of the dye malachite green attaining 95.0% (at a rate constant of 0.091 min-1) and 87.6% (at a rate constant of 0.017 min-1) using NPs obtained by the sol-gel and solvothermal methods, respectively. Adsorption in the dark accounted for 89.2% of the dye removal for nanoparticles prepared by sol-gel and 82.8% for the ones obtained by the solvothermal method. These results make mixed zinc/magnesium ferrites highly promising for potential industrial application in effluent photoremediation using visible light.

2.
J Pers Med ; 14(6)2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38929871

RESUMEN

Obesity is a worldwide epidemic, and bariatric surgery is considered the primary treatment for long-term weight loss and managing obesity-related health issues. Sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) are the most performed procedures. Nutritional deficiencies are a significant concern following bariatric surgery and can have serious consequences. This study aims to compare the incidence of nutritional deficiencies in patients undergoing RYGB and SG. A retrospective analysis was conducted on the nutritional status of 505 consecutive patients who underwent either RYGB or SG between January and December 2019. Data were collected regarding vitamin B12, folic acid, vitamin D, calcium, PTH, magnesium, hemoglobin, iron, ferritin, and transferrin at preoperative, 6-month, and 12-month intervals post-surgery. The RYGB group showed significantly higher excess weight loss. Vitamin B12, hemoglobin, and ferritin levels were consistently higher in the SG group throughout the study. Vitamin D deficiency was prevalent, with no significant difference between the groups. Vitamin B12 deficiency was significantly more common in the RYGB group (6 months: 17.46% vs. 4.69%, p < 0.001; 12 months: 16.74% vs. 0.93%, p < 0.001). Despite differences in their mechanisms, bariatric surgeries were associated with nutritional deficiencies. It is crucial to efficiently assess, prevent, and manage these deficiencies tailored to each surgical procedure.

3.
Microorganisms ; 12(6)2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38930449

RESUMEN

Environmental decontamination and water disinfection practices are hallmarks of disease prevention and control in agricultural and public health settings. Informed fit-to-purpose biocontainment is thus dependent on methodologies accurately assessing microbial burden and viability. Also, rigorous evaluation of the efficacy of biocontrol measures implies monitoring microbial inactivation after decontamination/disinfection procedures. In this study, we used flow cytometry coupled with a resuscitation protocol to monitor the metabolic inactivation of bacteria capable of entering non-cultivable states, after the application of a chlorine-based water disinfectant. For this purpose, we used Mycobacterium bovis BCG as a model of slow-growing bacteria able to enter dormancy and representing a multi-host pathogen in a zoonotic disease system-animal tuberculosis-thriving both across temperate and semi-arid regions and involving environmental contamination. The biocide activity of a commercial sodium dichloroisocyanurate (NaDCC) disinfectant against M. bovis BCG was evaluated through mock environmental matrix tests. Using the manufacturer-recommended dosage of NaDCC, BCG cells were apparently inactivated after 24 h upon exposure. However, we show via flow cytometry that, upon exposure to optimal growth conditions, mycobacterial cells were able to regain metabolic activity shortly after, highlighting a sublethal effect of NaDCC at the recommended commercial dosage due to reversible BCG cell damage. In contrast, increasing twice the disinfectant dosage completely inactivated BCG cells after 24 h of exposure, with full irreversible loss of metabolic activity. Methodological workflows based on conventional culture or PCR would have missed the detection of these dormant subpopulations that were in fact able to resume growth when following the recommendations of a commercial disinfectant. This study highlights the superior, high-resolution value of single-cell approaches, such as flow cytometry, to accurately assess the activity of biocides against metabolically heterogeneous and dormant pathogenic bacteria with environmental cycles, supporting data-driven prioritization of environmental management and disinfection options in contaminated vulnerable settings.

4.
Toxics ; 12(6)2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38922095

RESUMEN

In recent years, contaminants of emerging concern have been reported in several environmental matrices due to advances in analytical methodologies. These anthropogenic micropollutants are detected at residual levels, representing an ecotoxicological threat to aquatic ecosystems. In particular, the pharmacotherapeutic group of non-steroidal anti-inflammatories (NSAIDs) is one of the most prescribed and used, as well as one of the most frequently detected in the aquatic environment. Bivalves have several benefits as a foodstuff, and also as an environment bioindicator species. Therefore, they are regarded as an ideal tool to assess this issue from both ecotoxicological and food safety perspectives. Thus, the control of these residues in bivalves is extremely important to safeguard environmental health, also ensuring food safety and public health. This paper aims to review NSAIDs in bivalves, observing their consumption, physicochemical characteristics, and mechanisms of action; their environmental occurrence in the aquatic environment and aquatic biota; and their effects on the ecosystem and the existent legal framework. A review of the analytical methodologies for the determination of NSAIDs in bivalves is also presented.

5.
Biology (Basel) ; 13(6)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38927334

RESUMEN

The ECPGR European Evaluation Network (EVA) for Maize involves genebanks, research institutions, and private breeding companies from nine countries focusing on the valorization of maize genetic resources across Europe. This study describes a diverse collection of 626 local landraces and traditional varieties of maize (Zea mays L.) from nine European genebanks, including criteria for selection of the collection and its genetic and phenotypic diversity. High-throughput pool genotyping grouped the landraces into nine genetic groups with a threshold of 0.6 admixture, while 277 accessions were designated admixed and likely to have resulted from previous breeding activities. The grouping correlated well with the geographic origins of the collection, also reflecting the various pathways of introduction of maize to Europe. Phenotypic evaluations of 588 accessions for flowering time and plant architecture in multilocation trials over three years confirmed the great diversity within the collection, although phenotypic clusters only partially correlated with the genetic grouping. The EVA approach promotes conservation of genetic resources and opens an opportunity to increase genetic variability for developing improved varieties and populations for farmers, with better adaptation to specific environments and greater tolerance to various stresses. As such, the EVA maize collection provides valuable sources of diversity for facing climate change due to the varieties' local adaptation.

6.
J Plast Reconstr Aesthet Surg ; 95: 221-230, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38936333

RESUMEN

BACKGROUND: Current indications of maxillary reconstruction with scapular tip free flap (STFF) are palatoalveolar defects associated with zygomaticomaxillary buttress and/or orbital floor defects. STFF can be placed either horizontally or vertically. Horizontal placement usually allows ideal palatal conformation, preventing oronasal communication, but has been argued to compromise orbital support and projection of the midface, whereas vertical placement is advocated for midface support but may be insufficient for the complete closure of the palate. The present study focuses on the horizontal placing of STFF to allow complete palate reconstruction and fistulae prevention while still obtaining optimal midface projection and orbital support. MATERIALS AND METHODS: This study included 21 case complex maxillary reconstructions with this flap, in which the horizontally placed scapular tip component replaced the palate, a muscular flap component was included for midface volume restoration, and an alloplastic implant was utilized for supporting the orbital content when needed. RESULTS: None of the patients presented palatal fistulas or alterations in the orbital support. CONCLUSION: A multilevel approach was proposed according to the maxillectomy defect. This experience supported the horizontal insetting of STFF to allow palatal fistulae prevention while still obtaining an optimal midface projection and orbital support.

7.
Microbiol Spectr ; 12(7): e0382923, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38771094

RESUMEN

Mycobacterium bovis causes animal tuberculosis in livestock and wildlife, with an impact on animal health and production, wildlife management, and public health. In this work, we sampled a multi-host tuberculosis community from the official hotspot risk area of Portugal over 16 years, generating the largest available data set in the country. Using phylogenetic and ecological modeling, we aimed to reconstruct the history of circulating lineages across the livestock-wildlife interface to inform intervention and the implementation of genomic surveillance within the official eradication plan. We find evidence for the co-circulation of M. bovis European 1 (Eu1), Eu2, and Eu3 clonal complexes, with Eu3 providing sufficient temporal signal for further phylogenetic investigation. The Eu3 most recent common ancestor (bovine) was dated in the 1990s, subsequently transitioning to wildlife (red deer and wild boar). Isolate clustering based on sample metadata was used to inform phylogenetic inference, unravelng frequent transmission between two clusters that represent an ecological corridor of previously unrecognized importance in Portugal. The latter was associated with transmission at the livestock-wildlife interface toward locations with higher temperature and precipitation, lower agriculture and road density, and lower host densities. This is the first analysis of M. bovis Eu3 complex in Iberia, shedding light on background ecological factors underlying long-term transmission and informing where efforts could be focused within the larger hotspot risk area of Portugal. IMPORTANCE: Efforts to strengthen surveillance and control of animal tuberculosis (TB) are ongoing worlwide. Here, we developed an eco-phylodynamic framework based on discrete phylogenetic approaches informed by M. bovis whole-genome sequence data representing a multi-host transmission system at the livestock-wildlife interface, within a rich ecological landscape in Portugal, to understand transmission processes and translate this knowledge into disease management benefits. We find evidence for the co-circulation of several M. bovis clades, with frequent transmission of the Eu3 lineage among cattle and wildlife populations. Most transition events between different ecological settings took place toward host, climate and land use gradients, underscoring animal TB expansion and a potential corridor of unrecognized importance for M. bovis maintenance. Results stress that animal TB is an established wildlife disease without ecological barriers, showing that control measures in place are insufficient to prevent long-distance transmission and spillover across multi-host communities, demanding new interventions targeting livestock-wildlife interactions.


Asunto(s)
Animales Salvajes , Mycobacterium bovis , Filogenia , Portugal/epidemiología , Animales , Mycobacterium bovis/genética , Mycobacterium bovis/clasificación , Mycobacterium bovis/aislamiento & purificación , Bovinos , Animales Salvajes/microbiología , Ganado/microbiología , Tuberculosis Bovina/transmisión , Tuberculosis Bovina/microbiología , Tuberculosis Bovina/epidemiología , Ciervos/microbiología , Sus scrofa/microbiología , Tuberculosis/transmisión , Tuberculosis/microbiología , Tuberculosis/epidemiología , Tuberculosis/veterinaria
8.
ACS Appl Eng Mater ; 2(4): 1170-1189, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38693992

RESUMEN

The expansion of the Internet of Things market and the proliferation of wearable technologies have generated a significant demand for textile-based energy storage systems. This work reports the engineered design of hybrid electrode nanomaterials of N-doped carbon nanotubes (CNT-N) functionalized with two types of manganese oxides (MOs)-birnessite (MnO2) and hausmannite (Mn3O4)-and their application in solid-state textile-based hybrid supercapacitors (SCs). A versatile citric acid-mediated eco-friendly one-pot aqueous precipitation process is proposed for the fabrication of the hybrids. Remarkably, different types of MOs were obtained by simply changing the reaction temperature from room temperature to 100 °C, without any post-thermal treatment. Asymmetric textile SCs were developed using cotton fabrics coated with CNT-N and the hybrids as textile electrodes, and poly(vinyl) alcohol/orthophosphoric acid as the solid-gel electrolyte. The asymmetric devices presented enhanced energy storage performance relative to the symmetric device based on CNT-N and excellent cycling stability (>96%) after 8000 charge/discharge cycles owing to synergistic effects between CNT-N and the MOs, which endowed nonfaradaic and pseudocapacitive features to the SCs. The asymmetric SC based on CNT-N@MnO2 featured 47% higher energy density and comparable power density to the symmetric CNT-N-based device (8.70 W h cm-2 at 309.01 µW cm-2 vs. 5.93 W h cm-2 at 346.58 µW cm-2). The engineered hybrid CNT-N@MO nanomaterials and the eco-friendly citric acid-assisted one-pot precipitation route open promising prospects not only for energy storage, but also for (photo)(electro)catalysis, wastewater treatment, and (bio)sensing.

9.
Langenbecks Arch Surg ; 409(1): 163, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775865

RESUMEN

PURPOSE: Although bariatric surgery is an effective intervention for obesity, it comes with risks such as early postoperative bleeding (EPB). Identifying preoperative risk factors for this complication can help patients' risk stratification and optimization. We performed a systematic review and meta-analysis to find predictors for early postoperative bleeding after Roux-en-Y gastric bypass (RYGB). METHODS: We conducted a systematic review, searching PubMed, Cochrane Library, and Web of Science until November 2023. We performed a random-effects meta-analysis to explore preoperative risk factors associated with early postoperative bleeding after RYGB. Sources of heterogeneity were explored by leave-one-out analyses. RESULTS: 23 studies were included, comprising 232,488 patients. Male gender (meta-analytical RR = 1.42, 95%CI = 1.21-1.66, I2 = 18%, Q Cochran test p-value = 0.29) and revisional surgery (meta-analytical RR = 1.35, 95%CI = 1.12-1.62, I2 = 22%, Q Cochran test p = 0.21) were associated with higher risk of EPB. On average, patients with EPB were older than the remainder (MD for the mean age = 2.82 years, 95%CI = 0.97-4.67, I2 = 0.00%, Q Cochran test p = 0.46). Except for hypertension (meta-analytical RR = 1.33, 95%CI = 1.02-1.73, I2 = 66%, Q Cochran test p < 0.0001), comorbidities were not associated with a higher risk of EPB. CONCLUSION: Preoperative risk factors, including age, gender, hypertension, and revisional bariatric surgery, are associated with early postoperative bleeding after RYGB. Further primary studies, with higher methodological quality, are required to detail more risk factors.


Asunto(s)
Derivación Gástrica , Hemorragia Posoperatoria , Humanos , Derivación Gástrica/efectos adversos , Factores de Riesgo , Hemorragia Posoperatoria/etiología , Hemorragia Posoperatoria/epidemiología , Obesidad Mórbida/cirugía , Medición de Riesgo
10.
J Hazard Mater ; 472: 134473, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38703681

RESUMEN

Spreading of Mycobacterium bovis causing animal tuberculosis (TB) at livestock-wildlife-environment interfaces remains a significant problem. Recently, we provided evidence of widespread environmental contamination of an endemic animal TB setting with viable and dormant M. bovis cells able to recover metabolic activity, making indirect transmission via environmental contamination plausible. We now report the first whole genome sequences of M. bovis recovered from the environment. We establish epidemiological links at the environment-animal interface by phylogenomic comparison of these M. bovis genomes with those isolated from livestock and wild ungulates from the same area. Environmental and animal genomes are highly intertwined and distribute similarly into the same M. bovis lineages, supporting several instances of environmental contamination. This study provides compelling evidence of M. bovis excretion into the environment and viability maintenance, supporting the environment as a potential source of new infection. These insights have clear implications for policy formulation, advocating environmental surveillance and an ecosystem perspective in TB control programs. ENVIRONMENTAL IMPLICATION: We report the first whole genome sequences of M. bovis from the environment and establish epidemiological links at the environment-animal interface, demonstrating close phylogenomic relatedness of animal and environmental M. bovis. Definitive evidence of M. bovis excretion into the environment with viability maintenance is provided, supporting the environment as a potential source of new infection. Implications of this work include methodological innovations offering a tool to resolve indirect transmission chains and support customized biosecurity measures. Policy formulation aiming at the control of animal tuberculosis and cost mitigation should consider these findings, encouraging environmental surveillance in official eradication programmes.


Asunto(s)
Mycobacterium bovis , Filogenia , Secuenciación Completa del Genoma , Mycobacterium bovis/genética , Animales , Genoma Bacteriano , Tuberculosis Bovina/transmisión , Tuberculosis Bovina/microbiología , Tuberculosis/transmisión , Tuberculosis/microbiología , Bovinos , Microbiología Ambiental , Animales Salvajes/microbiología
11.
Materials (Basel) ; 17(10)2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38793510

RESUMEN

In recent years, tubular nanostructures have been related to immense advances in various fields of science and technology. Considerable research efforts have been centred on the theoretical prediction and manufacturing of non-carbon nanotubes (NTs), which meet modern requirements for the development of novel devices and systems. In this context, diatomic inorganic nanotubes formed by atoms of elements from the 13th group of the periodic table (B, Al, Ga, In, Tl) and nitrogen (N) have received much research attention. In this study, the elastic properties of single-walled boron nitride, aluminium nitride, gallium nitride, indium nitride, and thallium nitride nanotubes were assessed numerically using the nanoscale continuum modelling approach (also called molecular structural mechanics). The elastic properties (rigidities, surface Young's and shear moduli, and Poisson's ratio) of nitride nanotubes are discussed with respect to the bond length of the corresponding diatomic hexagonal lattice. The results obtained contribute to a better understanding of the mechanical response of nitride compound-based nanotubes, covering a broad range, from the well-studied boron nitride NTs to the hypothetical thallium nitride NTs.

12.
Int J Mol Sci ; 25(7)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38612679

RESUMEN

Epidemiological surveillance of animal tuberculosis (TB) based on whole genome sequencing (WGS) of Mycobacterium bovis has recently gained track due to its high resolution to identify infection sources, characterize the pathogen population structure, and facilitate contact tracing. However, the workflow from bacterial isolation to sequence data analysis has several technical challenges that may severely impact the power to understand the epidemiological scenario and inform outbreak response. While trying to use archived DNA from cultured samples obtained during routine official surveillance of animal TB in Portugal, we struggled against three major challenges: the low amount of M. bovis DNA obtained from routinely processed animal samples; the lack of purity of M. bovis DNA, i.e., high levels of contamination with DNA from other organisms; and the co-occurrence of more than one M. bovis strain per sample (within-host mixed infection). The loss of isolated genomes generates missed links in transmission chain reconstruction, hampering the biological and epidemiological interpretation of data as a whole. Upon identification of these challenges, we implemented an integrated solution framework based on whole genome amplification and a dedicated computational pipeline to minimize their effects and recover as many genomes as possible. With the approaches described herein, we were able to recover 62 out of 100 samples that would have otherwise been lost. Based on these results, we discuss adjustments that should be made in official and research laboratories to facilitate the sequential implementation of bacteriological culture, PCR, downstream genomics, and computational-based methods. All of this in a time frame supporting data-driven intervention.


Asunto(s)
Coinfección , Mycobacterium bovis , Tuberculosis , Animales , Mycobacterium bovis/genética , Tuberculosis/epidemiología , Tuberculosis/veterinaria , ADN , Genómica
13.
Nanomaterials (Basel) ; 14(8)2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38668215

RESUMEN

We report a joint high-pressure experimental and theoretical study of the structural, vibrational, and photoluminescent properties of pure and Eu3+-doped cubic Y2O3 nanoparticles with two very different average particle sizes. We compare the results of synchrotron X-ray diffraction, Raman scattering, and photoluminescence measurements in nanoparticles with ab initio density-functional simulations in bulk material with the aim to understand the influence of the average particle size on the properties of pure and doped Y2O3 nanoparticles under compression. We observe that the high-pressure phase behavior of Y2O3 nanoparticles depends on the average particle size, but in a different way to that previously reported. Nanoparticles with an average particle size of ~37 nm show the same pressure-induced phase transition sequence on upstroke and downstroke as the bulk sample; however, nanoparticles with an average particle size of ~6 nm undergo an irreversible pressure-induced amorphization above 16 GPa that is completed above 24 GPa. On downstroke, 6 nm nanoparticles likely consist of an amorphous phase.

14.
Cereb Cortex ; 34(3)2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38501383

RESUMEN

A key question in research on the neurobiology of language is to which extent the language production and comprehension systems share neural infrastructure, but this question has not been addressed in the context of conversation. We utilized a public fMRI dataset where 24 participants engaged in unscripted conversations with a confederate outside the scanner, via an audio-video link. We provide evidence indicating that the two systems share neural infrastructure in the left-lateralized perisylvian language network, but diverge regarding the level of activation in regions within the network. Activity in the left inferior frontal gyrus was stronger in production compared to comprehension, while comprehension showed stronger recruitment of the left anterior middle temporal gyrus and superior temporal sulcus, compared to production. Although our results are reminiscent of the classical Broca-Wernicke model, the anterior (rather than posterior) temporal activation is a notable difference from that model. This is one of the findings that may be a consequence of the conversational setting, another being that conversational production activated what we interpret as higher-level socio-pragmatic processes. In conclusion, we present evidence for partial overlap and functional asymmetry of the neural infrastructure of production and comprehension, in the above-mentioned frontal vs temporal regions during conversation.


Asunto(s)
Comprensión , Imagen por Resonancia Magnética , Humanos , Comprensión/fisiología , Imagen por Resonancia Magnética/métodos , Comunicación , Lenguaje , Corteza Prefrontal , Mapeo Encefálico
15.
EPMA J ; 15(1): 135-148, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38463621

RESUMEN

Multidisciplinary team from three universities based in the "Centro" Region of Portugal developed diverse approaches as parts of a project dedicated to enhancing and expanding Predictive, Preventive, and Personalized Medicine (3PM) in the Region. In a sense, outcomes acted as a proof-of-concept, in that they demonstrated the feasibility, but also the relevance of the approaches. The accomplishments comprise defining a new regional strategy for implementing 3PM within the Region, training of human resources in genomic sequencing, and generating good practices handbooks dedicated to diagnostic testing via next-generation sequencing, to legal and ethical concerns, and to knowledge transfer and entrepreneurship, aimed at increasing literacy on 3PM approaches. Further approaches also included support for entrepreneurship development and start-ups, and diverse and relevant initiatives aimed at increasing literacy relevant to 3PM. Efforts to enhance literacy encompassed citizens across the board, from patients and high school students to health professionals and health students. This focus on empowerment through literacy involved a variety of initiatives, including the creation of an illustrated book on genomics and the production of two theater plays centered on genetics. Additionally, authors stressed that genomic tools are relevant, but they are not the only resources 3PM is based on. Thus, they defend that other initiatives intended to enable citizens to take 3PM should include multi-omics and, having in mind the socio-economic burden of chronic diseases, suboptimal health status approaches in the 3PM framework should also be considered, in order to anticipate medical intervention in the subclinical phase. Supplementary Information: The online version contains supplementary material available at 10.1007/s13167-024-00353-9.

16.
Materials (Basel) ; 17(4)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38399050

RESUMEN

Two-dimensional (2D) nanostructures of aluminum nitride (AlN) and gallium nitride (GaN), called nanosheets, have a graphene-like atomic arrangement and represent novel materials with important upcoming applications in the fields of flexible electronics, optoelectronics, and strain engineering, among others. Knowledge of their mechanical behavior is key to the correct design and enhanced functioning of advanced 2D devices and systems based on aluminum nitride and gallium nitride nanosheets. With this background, the surface Young's and shear moduli of AlN and GaN nanosheets over a wide range of aspect ratios were assessed using the nanoscale continuum model (NCM), also known as the molecular structural mechanics (MSM) approach. The NCM/MSM approach uses elastic beam elements to represent interatomic bonds and allows the elastic moduli of nanosheets to be evaluated in a simple way. The surface Young's and shear moduli calculated in the current study contribute to building a reference for the evaluation of the elastic moduli of AlN and GaN nanosheets using the theoretical method. The results show that an analytical methodology can be used to assess the Young's and shear moduli of aluminum nitride and gallium nitride nanosheets without the need for numerical simulation. An exploratory study was performed to adjust the input parameters of the numerical simulation, which led to good agreement with the results of elastic moduli available in the literature. The limitations of this method are also discussed.

17.
Laryngoscope ; 134(8): 3458-3465, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38381055

RESUMEN

OBJECTIVE: Cochlear implant surgery is guided by principles of atraumatic insertion as to protect the inner ear. Previous studies suggest the potential benefit of steroids in patients undergoing cochlear implantation (CI), although the optimal route of administration has yet to be determined. We aim to systematically review the human studies of hearing and vestibular function preservation in patients undergoing CI receiving perioperative steroids and to discuss their role. DATA SOURCES: Search performed in PubMed, EMBASE, and CENTRAL databases in December 2023. REVIEW METHODS: Studies comparing several methods of steroid delivery and conventional management for patients undergoing CI were identified. Primary outcomes included hearing and vestibular function preservation. Secondary outcomes included reported adverse events, routes of steroid administration, and the presence of a control group without steroid administration. RESULTS: A total of 15 studies (N = 659) met inclusion criteria. Methodology, doses, route of steroid administration, and follow-up duration differed between most studies. Audiometric, vestibular, and hearing preservation (HP) results were inconsistent. In 12 studies, perioperative steroids were associated with either increased HP or vestibular function preservation. Only two studies reported adverse events related to oral corticosteroid therapy. CONCLUSIONS: There is a tendency for perioperative steroids to have a positive impact, at least in the short term, on hearing and vestibular function preservation in CI. Topical corticosteroid therapy appears to have a superior risk-benefit profile. There is a need for future carefully designed randomized controlled trials to determine the ideal route of steroid administration and its real impact in the long term. Laryngoscope, 134:3458-3465, 2024.


Asunto(s)
Implantación Coclear , Audición , Vestíbulo del Laberinto , Humanos , Implantación Coclear/efectos adversos , Implantación Coclear/métodos , Audición/efectos de los fármacos , Vestíbulo del Laberinto/efectos de los fármacos , Pérdida Auditiva/prevención & control , Pérdida Auditiva/cirugía , Glucocorticoides/administración & dosificación , Glucocorticoides/efectos adversos
18.
Cureus ; 16(1): e52670, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38380189

RESUMEN

Anorexia nervosa (AN) belongs to the spectrum of food disorders and affects approximately 2.9 million people worldwide. It is responsible for numerous and serious medical complications. Osteoporosis is a common complication, and the decrease in bone mineral density (BMD) is one of the few potentially irreversible consequences of AN. When associated with AN, it can manifest at a very young age, possibly leading to irreparable damage. We describe the case of a 30-year-old woman with a one-year evolution diagnosis of AN, complaining of back pain. Physical examination revealed a slight elevation of the right shoulder and pain at compression of paravertebral right dorsal musculature with a palpable strained muscle. Full-length X-ray imaging of the dorsal spine revealed a slight dextroconvex dorsolumbar scoliosis. A dorsal spine computerized tomography (CT) was performed, confirming a fracture of the upper platform of the sixth dorsal vertebrae. Osteodensitometry showed lumbar spine osteoporosis and femoral osteopenia. The decrease in BMD and, later on, the development of osteoporosis can occur in both types of AN. It is a severe complication that affects up to 50% of these patients. It can be irreversible and increase the lifetime risk of bone fractures and, therefore, morbimortality. Low body weight and body mass index (BMI) strongly correlate with the decrease in BMD. Treatment of osteoporosis associated with AN is not standardized and clearly labeled. Weight gain is described as the strategy with the most impact in reversing the loss of bone mass and increasing the BMD. The regularization of gonadal function also seems to independently potentiate the increase of BMD. The occurrence of long bone and vertebrae fractures frequently results in a decrease in height and chronic back pain, culminating in greater morbimortality and healthcare costs. This clinical case aims to show theclose relationship between restrictive food disorders and the decrease of BMD and the subsequent development of osteoporosis and its complications. Although rare in young and healthy people, when associated with restrictive food disorders, it should raise a red flag in its clinical evaluation. Preventing osteoporosis development and reduction of fracture risk in this population is essential. The current absence of consistent evidence regarding screening of osteoporosis in this particular group should raise awareness and promote further larger-scale studies to establish standardized recommendations concerning not only screening but also pharmacological treatment of osteoporosis in patients with AN.

19.
Animals (Basel) ; 14(3)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38338000

RESUMEN

The tadpole shrimp Triops longicaudatus is a freshwater crustacean with fast embryonic and larval development, short life cycle, and high fecundity. They are very active swimmers of a reasonable size, easy to spot and record. Such characteristics make it a promising candidate as an experimental model in ecotoxicology to evaluate the effects of aquatic pollutants, particularly using its locomotor behavior as an endpoint. To evaluate the sensitivity of T. longicaudatus and develop endpoints of interest, we conducted exposure experiments with lethal and sub-lethal concentrations of potassium dichromate, a compound known for its ecotoxicological importance and as a hexavalent chromium source. The endpoints evaluated were mortality, growth, sexual maturation, reproductive output, cholinesterase activity and locomotor/swimming behavior. The 96 h median lethal concentration was found to be 65 µg/L. Furthermore, exposure to potassium dichromate at higher concentrations had a significant negative impact on the growth rate of T. longicaudatus in terms of both body mass and length. The time for maturation was also delayed at higher concentrations. In addition, locomotor behavior allowed for the discrimination of all tested chromium concentrations and the control group and from each other, proving to be the most sensitive endpoint. Overall, the data support the potential of T. longicaudatus as a model for ecotoxicity testing, using apical endpoints with impact at the population level; in particular, results suggest that behavior assessments in this species might be useful for detecting hazardous compounds in environmental monitoring of freshwater ecosystems.

20.
Artículo en Inglés | MEDLINE | ID: mdl-38346488

RESUMEN

OBJECTIVES: To compare the hearing outcomes of ossicular chain reconstruction using bone cement versus other materials such as prostheses and autografts. METHODS: This study included articles that compared hearing outcomes in patients with conductive hearing loss who underwent stapes revision surgery or chronic otitis media surgery. A systematic search for articles from January 2000 to February 2022 was conducted in Medline, Embase, and Cochrane Library databases. Only articles in English were included. An effective postoperative air-bone gap (ABG) was defined as ≤20 dB. A bias assessment tool was developed according to Cochrane guidelines, and the chi-square test was used to evaluate the mean age of the samples. RESULTS: Of the 418 studies that met the selection criteria, only seven were eligible for this study, consisting of 187 patients in the bone cement group and 173 in the non-bone cement group. Ossiculoplasty using bone cement yielded significantly better results, with a combined odds ratio (OR) of 2.03 (95% CI: 1.16-3.55, p = 0.01). CONCLUSIONS: The results of this study suggest that the effectiveness of bone cement in ossiculoplasty was greater than that of other materials in chronic otitis media surgery or stapes revision surgery, with a higher number of patients achieving ABG ≤20 dB.

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