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1.
J Clin Med ; 13(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38592026

RESUMO

Background: Evaluating the predictors of unfavorable outcomes in patients with ankle fractures is crucial for identifying high-risk patients and implementing personalized treatment strategies. This study aimed to analyze factors that influence quality of life in patients with ankle fractures. Methods: Four databases were consulted. The main outcomes were functionality and quality of life scales combined using the standard mean difference (SMD) (Review Manager 5.4). Results: Eight studies with 2486 patients were included. A significant correlation was found between female sex and worse functionality scores (beta 4.15, 95% CI 1.84-6.46). Additionally, older age was correlated with worse functionality scores (beta -0.24, 95% CI -0.29 to -0.19). Patients with diabetes or metabolic syndrome also had worse outcomes (SMD 0.27, 95% CI 0.18-0.36). High BMI and obesity were also associated with worse quality of life scores (beta 2.62, 95% CI 0.77-4.48). Smokers had greater disability in the analyzed scales (SMD 0.22, 95% CI 0.05-0.39). No significant differences were observed with respect to syndesmotic involvement. Conclusions: Age, sex, diabetes, high BMI, and smoking negatively impact functional outcomes and quality of life in patients with ankle fractures.

2.
Front Immunol ; 15: 1364774, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38629075

RESUMO

Allergic asthma has emerged as a prevalent allergic disease worldwide, affecting most prominently both young individuals and lower-income populations in developing and developed countries. To devise effective and curative immunotherapy, it is crucial to comprehend the intricate nature of this condition, characterized by an immune response imbalance that favors a proinflammatory profile orchestrated by diverse subsets of immune cells. Although the involvement of Natural Killer T (NKT) cells in asthma pathology is frequently implied, their specific contributions to disease onset and progression remain incompletely understood. Given their remarkable ability to modulate the immune response through the rapid secretion of various cytokines, NKT cells represent a promising target for the development of effective immunotherapy against allergic asthma. This review provides a comprehensive summary of the current understanding of NKT cells in the context of allergic asthma, along with novel therapeutic approaches that leverage the functional response of these cells.


Assuntos
Asma , Hipersensibilidade , Células T Matadoras Naturais , Humanos , Hipersensibilidade/terapia , Citocinas , Imunoterapia
3.
J Clin Med ; 13(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38398273

RESUMO

(1) Objectives: The objective of this study was to quantify the exact clinical-radiological efficacy and safety of the extreme lateral interbody fusion (XLIF) technique in spinal surgery; (2) Methods: A meta-analysis was performed using PubMed, Embase, Scopus, and Cochrane Collaboration Library. Studies focusing on patients surgically treated with XLIF were included. The outcomes were as follows: visual analog scale (VAS) and Oswestry disability index (ODI), radiological outcomes, and adverse events. Cohort studies and case series were also included. Clinical outcomes were assessed at 12 months of age. Data were combined using Review Manager 5.4 and WebPlotDigitizer 13.1.4; (3) Results: Nineteen studies with a pool of 1409 patients were included in this meta-analysis. Leg pain VAS and back pain VAS significantly improved at 12 months (SMD 2.75, 95% CI 0.59-4.90; SMD 4.54, 95% CI 1.39-7.69). ODI showed significant improvement (MD 32.51, 95% CI 24.01-41.00) at 12 months. Disc height increased significantly (SMD -2.73, 95% CI -3.58 to -1.88). Lumbar lordosis and segmental lordosis were significantly corrected postoperatively (MD -2.44, 95% CI -3.45 to -1.43; MD -2.55, 95% CI -3.61 to -1.48). The fusion rates at 12 months ranged from 85.0% to 93.3%. The most frequent complications were transient neurological conditions (2.2%), hardware failure (1.9%), and transient pain (1.8%). The most frequent serious complications were nerve root injury (1.0%), gastrointestinal impairment (0.7%), and vertebral fractures (0.6%); (4) Conclusions: This is the first meta-analysis of the specific use of XLIF in spinal surgery. This study demonstrates that the XLIF technique in spine surgery is associated with good clinical and radiological results and a low complication rate.

4.
Nat Commun ; 15(1): 327, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184663

RESUMO

Soil fungi are a key constituent of global biodiversity and play a pivotal role in agroecosystems. How arable farming affects soil fungal biogeography and whether it has a disproportional impact on rare taxa is poorly understood. Here, we used the high-resolution PacBio Sequel targeting the entire ITS region to investigate the distribution of soil fungi in 217 sites across a 3000 km gradient in Europe. We found a consistently lower diversity of fungi in arable lands than grasslands, with geographic locations significantly impacting fungal community structures. Prevalent fungal groups became even more abundant, whereas rare groups became fewer or absent in arable lands, suggesting a biotic homogenization due to arable farming. The rare fungal groups were narrowly distributed and more common in grasslands. Our findings suggest that rare soil fungi are disproportionally affected by arable farming, and sustainable farming practices should protect rare taxa and the ecosystem services they support.


Assuntos
Ecossistema , Solo , Agricultura , Europa (Continente) , Fazendas
5.
Nat Ecol Evol ; 8(3): 411-422, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38195996

RESUMO

Evidence is mounting that vertebrate defaunation greatly impacts global biogeochemical cycling. Yet, there is no comprehensive assessment of the potential vertebrate influence over plant decomposition, despite litter decay being one of the largest global carbon fluxes. We therefore conducted a global meta-analysis to evaluate vertebrate effects on litter mass loss and associated element release across terrestrial and aquatic ecosystems. Here we show that vertebrates affected litter decomposition by various direct and indirect pathways, increasing litter mass loss by 6.7% on average, and up to 34.4% via physical breakdown. This positive vertebrate impact on litter mass loss was consistent across contrasting litter types (woody and non-woody), climatic regions (boreal, temperate and tropical), ecosystem types (aquatic and terrestrial) and vertebrate taxa, but disappeared when evaluating litter nitrogen and phosphorus release. Moreover, we found evidence of interactive effects between vertebrates and non-vertebrate decomposers on litter mass loss, and a larger influence of vertebrates at mid-to-late decomposition stages, contrasting with the invertebrate effect known to be strongest at early decomposition stage. Our synthesis demonstrates a global vertebrate control over litter mass loss, and further stresses the need to account for vertebrates when assessing the impacts of biodiversity loss on biogeochemical cycles.


Assuntos
Ecossistema , Plantas , Animais , Plantas/metabolismo , Biodiversidade , Vertebrados , Nitrogênio/metabolismo
6.
Glob Chang Biol ; 30(1): e16989, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37888833

RESUMO

Anthropogenic nitrogen (N) loading alters soil ammonia-oxidizing archaea (AOA) and bacteria (AOB) abundances, likely leading to substantial changes in soil nitrification. However, the factors and mechanisms determining the responses of soil AOA:AOB and nitrification to N loading are still unclear, making it difficult to predict future changes in soil nitrification. Herein, we synthesize 68 field studies around the world to evaluate the impacts of N loading on soil ammonia oxidizers and nitrification. Across a wide range of biotic and abiotic factors, climate is the most important driver of the responses of AOA:AOB to N loading. Climate does not directly affect the N-stimulation of nitrification, but does so via climate-related shifts in AOA:AOB. Specifically, climate modulates the responses of AOA:AOB to N loading by affecting soil pH, N-availability and moisture. AOB play a dominant role in affecting nitrification in dry climates, while the impacts from AOA can exceed AOB in humid climates. Together, these results suggest that climate-related shifts in soil ammonia-oxidizing community maintain the N-stimulation of nitrification, highlighting the importance of microbial community composition in mediating the responses of the soil N cycle to N loading.


Assuntos
Amônia , Solo , Solo/química , Nitrificação , Nitrogênio/análise , Oxirredução , Microbiologia do Solo , Archaea , Filogenia
7.
Cancers (Basel) ; 15(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38136283

RESUMO

Invariant natural killer T cells (iNKTs), a type of unconventional T cells, share features with NK cells and have an invariant T cell receptor (TCR), which recognizes lipid antigens loaded on CD1d molecules, a major histocompatibility complex class I (MHC-I)-like protein. This interaction produces the secretion of a wide array of cytokines by these cells, including interferon gamma (IFN-γ) and interleukin 4 (IL-4), allowing iNKTs to link innate with adaptive responses. Interestingly, molecules that bind CD1d have been identified that enable the modulation of these cells, highlighting their potential pro-inflammatory and immunosuppressive capacities, as required in different clinical settings. In this review, we summarize key features of iNKTs and current understandings of modulatory α-galactosylceramide (α-GalCer) variants, a model iNKT cell activator that can shift the outcome of adaptive immune responses. Furthermore, we discuss advances in the development of strategies that modulate these cells to target pathologies that are considerable healthcare burdens. Finally, we recapitulate findings supporting a role for iNKTs in infectious diseases and tumor immunotherapy.

8.
Plast Reconstr Surg Glob Open ; 11(9): e5281, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37753332

RESUMO

Background: Plastic surgery and social media have become inextricably linked through patient procurement, practice growth, and academic exposure. Other surgical fields have demonstrated that tweeting is positively correlated with increased citations. This study aimed to elucidate the effect of Twitter on traditional bibliometrics in plastic surgery and parse out the kinds of tweets that are most correlated with citations. Methods: Articles from May to October of 2018 from Plastic and Reconstructive Surgery and Aesthetic Surgery Journal were analyzed to determine the citation count, number and backgrounds of Twitter users tweeting about the article, and total tweets. Multiple linear regression was performed to correlate these variables to citation count. Results: A total of 369 articles were analyzed. Plastic and Reconstructive Surgery had significantly more average tweets per article compared to Aesthetic Surgery Journal (21.8 versus 10.2, P < 0.001), Additionally, a number of tweets (r = 0.45, P < 0.001) and reaching more total followers (r = 0.48, P < 0.001) were both positively correlated with citations. Multiple linear regression demonstrated that tweets from self-identified scientists were positively correlated with citations (r = 0.99, P = 0.001). Tweets from science communicators had no correlation with citations (r = -0.012, P = 0.726). Tweets coming domestically from the country of the author were also associated with more citations (r = 0.164, P = 0.013). Conclusions: Twitter activity, including the number of followers reached, for an article is positively correlated with citations. Interestingly, the kind of person tweeting affected the citations as well. Domestic tweets and those from scientists were associated with more citations. This implies that Twitter can be an effective form of academic dissemination, provided the "right" Twitter users are promoting the article.

9.
Front Cell Infect Microbiol ; 13: 1229098, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37753486

RESUMO

Cellular senescence is a key biological process characterized by irreversible cell cycle arrest. The accumulation of senescent cells creates a pro-inflammatory environment that can negatively affect tissue functions and may promote the development of aging-related diseases. Typical biomarkers related to senescence include senescence-associated ß-galactosidase activity, histone H2A.X phosphorylation at serine139 (γH2A.X), and senescence-associated heterochromatin foci (SAHF) with heterochromatin protein 1γ (HP-1γ protein) Moreover, immune cells undergoing senescence, which is known as immunosenescence, can affect innate and adaptative immune functions and may elicit detrimental effects over the host's susceptibility to infectious diseases. Although associations between senescence and pathogens have been reported, clear links between both, and the related molecular mechanisms involved remain to be determined. Furthermore, it remains to be determined whether infections effectively induce senescence, the impact of senescence and immunosenescence over infections, or if both events coincidently share common molecular markers, such as γH2A.X and p53. Here, we review and discuss the most recent reports that describe cellular hallmarks and biomarkers related to senescence in immune and non-immune cells in the context of infections, seeking to better understand their relationships. Related literature was searched in Pubmed and Google Scholar databases with search terms related to the sections and subsections of this review.


Assuntos
Infecções Bacterianas , Imunossenescência , Humanos , Heterocromatina , Senescência Celular , Biomarcadores
10.
Front Immunol ; 14: 1186368, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37575242

RESUMO

Background: Shiga toxin-producing Escherichia coli (STEC) is a foodborne pathogen that causes gastrointestinal infections, ranging from acute diarrhea and dysentery to life-threatening diseases such as Hemolytic Uremic Syndrome. Currently, a vaccine to prevent STEC infection is an unmet medical need. Results: We developed a chimeric protein-based vaccine targeting seven virulence factors of STEC, including the Stx2B subunit, Tir, Intimin, EspA, Cah, OmpT, and AggA proteins. Immunization of mice with this vaccine candidate elicited significant humoral and cellular immune responses against STEC. High levels of specific IgG antibodies were found in the serum and feces of immunized mice. However, specific IgA antibodies were not detected in either serum or feces. Furthermore, a significantly higher percentage of antigen-specific CD4+ T cells producing IFN-γ, IL-4, and IL-17 was observed in the spleens of immunized mice. Notably, the immunized mice showed decreased shedding of STEC O157:H7 and STEC O91:H21 strains and were protected against weight loss during experimental infection. Additionally, infection with the STEC O91:H21 strain resulted in kidney damage in control unimmunized mice; however, the extent of damage was slightly lower in immunized mice. Our findings suggest that IgG antibodies induced by this vaccine candidate may have a role in inhibiting bacterial adhesion and complement-mediated killing. Conclusion: This study provides evidence that IgG responses are involved in the host defense against STEC. However, our results do not rule out that other classes of antibodies also participate in the protection against this pathogen. Additional work is needed to improve the protection conferred by our vaccine candidate and to elucidate the relevant immune responses that lead to complete protection against this pathogen.


Assuntos
Infecções por Escherichia coli , Escherichia coli Shiga Toxigênica , Vacinas , Animais , Camundongos , Imunoglobulina G , Formação de Anticorpos , Proteínas Recombinantes de Fusão
11.
Nanomaterials (Basel) ; 13(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37630896

RESUMO

A novel manufacturing process is presented for producing nanopowders and thin films of CuCoO2 (CCO) material. This process utilizes three cost-effective synthesis methods: hydrothermal, sol-gel, and solid-state reactions. The resulting delafossite CuCoO2 samples were deposited onto transparent substrates through spray pyrolysis, forming innovative thin films with a nanocrystal powder structure. Prior to the transformation into thin films, CuCoO2 powder was first produced using a low-cost approach. The precursors for both powders and thin films were deposited onto glass surfaces using a spray pyrolysis process, and their characteristics were examined through X-ray diffraction, scanning electron microscopy, HR-TEM, UV-visible spectrophotometry, and electrochemical impedance spectroscopy (EIS) analyses were conducted to determine the conductivity in the transversal direction of this groundbreaking material for solar cell applications. On the other hand, the sheet resistance of the samples was investigated using the four-probe method to obtain the sheet resistivity and then calculate the in-plane conductivity of the samples. We also investigated the aging characteristics of different precursors with varying durations. The functional properties of CuCoO2 samples were explored by studying chelating agent and precursor solution aging periods using Density Functional Theory calculations (DFT). A complementary Density Functional Theory study was also performed in order to evaluate the electronic structure of this compound. Resuming, this study thoroughly discusses the synthesis of delafossite powders and their conversion into thin films, which hold potential as hole transport layers in transparent optoelectronic devices.

12.
Ecosystems ; 26(3): 585-596, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37179798

RESUMO

Accumulating evidence suggests that warming associated with climate change is decreasing the total amount of soil organic carbon (SOC) in drylands, although scientific research has not given enough emphasis to particulate (POC) and mineral-associated organic carbon (MAOC) pools. Biocrusts are a major biotic feature of drylands and have large impacts on the C cycle, yet it is largely unknown whether they modulate the responses of POC and MAOC to climate change. Here, we assessed the effects of simulated climate change (control, reduced rainfall (RE), warming (WA), and RE + WA) and initial biocrust cover (low (< 20%) versus high (> 50%)) on the mineral protection of soil C and soil organic matter quality in a dryland ecosystem in central Spain for 9 years. At low initial biocrust cover levels, both WA and RE + WA increased SOC, especially POC but also MAOC, and promoted a higher contribution of carbohydrates, relative to aromatic compounds, to the POC fraction. These results suggest that the accumulation of soil C under warming treatments may be transitory in soils with low initial biocrust cover. In soils with high initial biocrust cover, climate change treatments did not affect SOC, neither POC nor MAOC fraction. Overall, our results indicate that biocrust communities modulate the negative effect of climate change on SOC, because no losses of soil C were observed with the climate manipulations under biocrusts. Future work should focus on determining the long-term persistence of the observed buffering effect by biocrust-forming lichens, as they are known to be negatively affected by warming. Supplementary Information: The online version contains supplementary material available at 10.1007/s10021-022-00779-0.

13.
J Clin Med ; 12(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37240680

RESUMO

Although open surgery is the conventional option for ankle arthritis, there are some reports in the literature regarding the use of the arthroscopy procedure with outstanding results. The primary purpose of this systematic review and meta-analysis was to analyze the effect of the surgery technique (open-ankle arthrodesis vs. arthroscopy) in patients with ankle osteoarthritis. Three electronic databases (PubMed, Web of Science, and Scopus) were searched until 10 April 2023. The Cochrane Collaboration's risk-of-bias tool was used to assess the risk of bias and grading of the recommendations assessment, development, and evaluation system for each outcome. The between-study variance was estimated using a random-effects model. A total of 13 studies (including n = 994 participants) met the inclusion criteria. The meta-analysis results revealed a nom-significant (p = 0.072) odds ratio (OR) of 0.54 (0.28-1.07) for the fusion rate. Regarding operation time, a non-significant difference (p = 0.573) among both surgical techniques was found (mean differences (MD) = 3.40 min [-11.08 to 17.88]). However, hospital length stay and overall complications revealed significant differences (MD = 2.29 days [0.63 to 3.95], p = 0.017 and OR = 0.47 [0.26 to 0.83], p = 0.016), respectively. Our findings showed a non-statistically significant fusion rate. On the other hand, operation time was similar among both surgical techniques, without significant differences. Nevertheless, lower hospital stay was found in patients that were operated on with arthroscopy. Finally, for the outcome of overall complications, the ankle arthroscopy technique was a protective factor in comparison with open surgery.

14.
Front Microbiol ; 14: 1065302, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36992926

RESUMO

Introduction: The microbiome inhabiting plant leaves is critical for plant health and productivity. Wild soybean (Glycine soja), which originated in China, is the progenitor of cultivated soybean (Glycine max). So far, the community structure and assembly mechanism of phyllosphere microbial community on G. soja were poorly understood. Methods: Here, we combined a national-scale survey with high-throughput sequencing and microsatellite data to evaluate the contribution of host genotype vs. climate in explaining the foliar microbiome of G. soja, and the core foliar microbiota of G. soja were identified. Results: Our findings revealed that both the host genotype and environmental factors (i.e., geographic location and climatic conditions) were important factors regulating foliar community assembly of G. soja. Host genotypes explained 0.4% and 3.6% variations of the foliar bacterial and fungal community composition, respectively, while environmental factors explained 25.8% and 19.9% variations, respectively. We further identified a core microbiome thriving on the foliage of all G. soja populations, including bacterial (dominated by Methylobacterium-Methylorubrum, Pantoea, Quadrisphaera, Pseudomonas, and Sphingomonas) and fungal (dominated by Cladosporium, Alternaria, and Penicillium) taxa. Conclusion: Our study revealed the significant role of host genetic distance as a driver of the foliar microbiome of the wild progenitor of soya, as well as the effects of climatic changes on foliar microbiomes. These findings would increase our knowledge of assembly mechanisms in the phyllosphere of wild soybeans and suggest the potential to manage the phyllosphere of soya plantations by plant breeding and selecting specific genotypes under climate change.

15.
Glob Chang Biol ; 29(11): 3177-3192, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36897740

RESUMO

Organic carbon and aggregate stability are key features of soil quality and are important to consider when evaluating the potential of agricultural soils as carbon sinks. However, we lack a comprehensive understanding of how soil organic carbon (SOC) and aggregate stability respond to agricultural management across wide environmental gradients. Here, we assessed the impact of climatic factors, soil properties and agricultural management (including land use, crop cover, crop diversity, organic fertilization, and management intensity) on SOC and the mean weight diameter of soil aggregates, commonly used as an indicator for soil aggregate stability, across a 3000 km European gradient. Soil aggregate stability (-56%) and SOC stocks (-35%) in the topsoil (20 cm) were lower in croplands compared with neighboring grassland sites (uncropped sites with perennial vegetation and little or no external inputs). Land use and aridity were strong drivers of soil aggregation explaining 33% and 20% of the variation, respectively. SOC stocks were best explained by calcium content (20% of explained variation) followed by aridity (15%) and mean annual temperature (10%). We also found a threshold-like pattern for SOC stocks and aggregate stability in response to aridity, with lower values at sites with higher aridity. The impact of crop management on aggregate stability and SOC stocks appeared to be regulated by these thresholds, with more pronounced positive effects of crop diversity and more severe negative effects of crop management intensity in nondryland compared with dryland regions. We link the higher sensitivity of SOC stocks and aggregate stability in nondryland regions to a higher climatic potential for aggregate-mediated SOC stabilization. The presented findings are relevant for improving predictions of management effects on soil structure and C storage and highlight the need for site-specific agri-environmental policies to improve soil quality and C sequestration.


Assuntos
Carbono , Solo , Solo/química , Agricultura , Sequestro de Carbono
16.
mBio ; 13(6): e0131122, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36383021

RESUMO

Multiple vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been evaluated in clinical trials. However, trials addressing the immune response in the pediatric population are scarce. The inactivated vaccine CoronaVac has been shown to be safe and immunogenic in a phase 1/2 clinical trial in a pediatric cohort in China. Here, we report interim safety and immunogenicity results of a phase 3 clinical trial for CoronaVac in healthy children and adolescents in Chile. Participants 3 to 17 years old received two doses of CoronaVac in a 4-week interval until 31 December 2021. Local and systemic adverse reactions were registered for volunteers who received one or two doses of CoronaVac. Whole-blood samples were collected from a subgroup of 148 participants for humoral and cellular immunity analyses. The main adverse reaction reported after the first and second doses was pain at the injection site. Four weeks after the second dose, an increase in neutralizing antibody titer was observed in subjects relative to their baseline visit. Similar results were found for activation of specific CD4+ T cells. Neutralizing antibodies were identified against the Delta and Omicron variants. However, these titers were lower than those for the D614G strain. Importantly, comparable CD4+ T cell responses were detected against these variants of concern. Therefore, CoronaVac is safe and immunogenic in subjects 3 to 17 years old, inducing neutralizing antibody secretion and activating CD4+ T cells against SARS-CoV-2 and its variants. (This study has been registered at ClinicalTrials.gov under no. NCT04992260.) IMPORTANCE This work evaluated the immune response induced by two doses of CoronaVac separated by 4 weeks in healthy children and adolescents in Chile. To date, few studies have described the effects of CoronaVac in the pediatric population. Therefore, it is essential to generate knowledge regarding the protection of vaccines in this population. Along these lines, we reported the anti-S humoral response and cellular immune response to several SARS-CoV-2 proteins that have been published and recently studied. Here, we show that a vaccination schedule consisting of two doses separated by 4 weeks induces the secretion of neutralizing antibodies against SARS-CoV-2. Furthermore, CoronaVac induces the activation of CD4+ T cells upon stimulation with peptides from the proteome of SARS-CoV-2. These results indicate that, even though the neutralizing antibody response induced by vaccination decreases against the Delta and Omicron variants, the cellular response against these variants is comparable to the response against the ancestral strain D614G, even being significantly higher against Omicron.


Assuntos
COVID-19 , SARS-CoV-2 , Adolescente , Humanos , Criança , Pré-Escolar , Anticorpos Neutralizantes , Vacinas de Produtos Inativados , Anticorpos Antivirais
17.
Proc Natl Acad Sci U S A ; 119(41): e2207089119, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36191199

RESUMO

Remitted waves are used for sensing and imaging in diverse diffusive media from the Earth's crust to the human brain. Separating the source and detector increases the penetration depth of light, but the signal strength decreases rapidly, leading to a poor signal-to-noise ratio. Here, we show, experimentally and numerically, that wavefront shaping a laser beam incident on a diffusive sample enables an enhancement of remission by an order of magnitude at depths of up to 10 transport mean free paths. We develop a theoretical model which predicts the maximal remission enhancement. Our analysis reveals a significant improvement in the sensitivity of remitted waves to local changes of absorption deep inside diffusive media. This work illustrates the potential of coherent wavefront control for noninvasive diffuse wave imaging applications, such as diffuse optical tomography and functional near-infrared spectroscopy.


Assuntos
Encéfalo , Difusão , Humanos , Razão Sinal-Ruído
18.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 33(5): 254-257, sept.-oct. 2022. ilus
Artigo em Espanhol | IBECS | ID: ibc-208217

RESUMO

La arteria ciática persistente es una entidad poco frecuente, considerada como una malformación vascular congénita de tipo axial por falta de involución de la arteria ciática durante el desarrollo embrionario. Puede, o no, asociarse con alteraciones en el desarrollo de las arterias iliaca, femoral común y/o femoral superficial. Clínicamente los pacientes pueden ser asintomáticos, o pueden manifestar un dolor crónico tipo neuralgia ciática, por irritación nerviosa, al estar en contigüidad con el vaso anómalamente persistente, o por dolor isquémico, al sufrir trombosis de un aneurisma que con relativa frecuencia suele desarrollarse en este vaso anómalamente persistente, o por embolia arterial distal, pudiendo llegar a comprometer la viabilidad de la extremidad (AU)


The persistent sciatic artery is an uncommon disease, considered an axial congenital vascular malformation due to the lack of involution of the sciatic artery during embryonic development. It may be associated with abnormalities in the development of the iliac, common femoral and superficial femoral arteries. Patients may be asymptomatic, or they could present chronic pain, such as sciatic neuralgia, caused by nerve damage, since it is close to the abnormal persistent vessel, or due to ischemic pain, as a result of a thrombosis or embolism of an aneurysm, which could compromise the viability of the limb (AU)


Assuntos
Humanos , Masculino , Adulto Jovem , Neuropatia Ciática/diagnóstico por imagem , Perna (Membro)/irrigação sanguínea , Angiografia por Tomografia Computadorizada , Ecocardiografia Doppler
19.
Nanomaterials (Basel) ; 12(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36079939

RESUMO

Antisolvent quenching has shown to significantly enhance several perovskite films used in solar cells; however, no studies have been conducted on its impact on MASnI3. Here, we investigated the role that different antisolvents, i.e., diethyl ether, toluene, and chlorobenzene, have on the growth of MASnI3 films. The crystallinity, morphology, topography, and optical properties of the obtained thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) measurements, and UV-visible spectroscopy. The impact of the different antisolvent treatments was evaluated based on the surface homogeneity as well as the structure of the MASnI3 thin films. In addition, thermal annealing was optimized to control the crystallization process. The applied antisolvent was modified to better manage the supersaturation process. The obtained results support the use of chlorobenzene and toluene to reduce pinholes and increase the grain size. Toluene was found to further improve the morphology and stability of thin films, as it showed less degradation after four weeks under dark with 60% humidity. Furthermore, we performed a simulation using SCAPS-1D software to observe the effect of these antisolvents on the performance of MASnI3-based solar cells. We also produced the device FTO/TiO2/MASnI3/Spiro-OMeTAD/Au, obtaining a remarkable photoconversion efficiency (PCE) improvement of 5.11% when using the MASnI3 device treated with chlorobenzene. A PCE improvement of 9.44% was obtained for the MASnI3 device treated with toluene, which also showed better stability. Our results support antisolvent quenching as a reproducible method to improve perovskite devices under ambient conditions.

20.
Nanomaterials (Basel) ; 12(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36080064

RESUMO

Presently, we inquire about the organic/inorganic cation effect on different properties based on structure, morphology, and steadiness in preparing a one-step solution of APbI3 thin films, where A = MA, FA, Cs, using spin coating. This study was conducted to understand those properties well by incorporating device modeling using SCAPS-1D software and to upgrade their chemical composition. X-ray diffraction (XRD) was used to analyze the crystal structures. Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) were conducted to characterize the surface morphology; photoluminescence, Transmission Electron Microscopy (TEM), and a UV-Visible spectrometer helped us to study the optical properties. The (110) plane is where we found the perovskite's crystalline structure. According to the XRD results and by changing the type of cation, we influence stabilization and the growth of the APbI3 absorber layer. Hither, a homogenous, smooth-surfaced, pinhole-free perovskite film and large grain size are results from the cesium cation. For the different cations, the band gap's range, revealed by the optical analysis, is from 1.4 to 1.8 eV. Moreover, the stability of CsPbI3 remains excellent for two weeks and in a ~60% humid environment. Based on the UV-Visible spectrometer and photoluminescence characterization, a numerical analysis for fabricated samples was also performed for stability analysis by modeling standard solar-cell structures HTL/APbI3/ETL. Modeling findings are in good agreement with experimental results that CsPbI3 is more stable, showing a loss % in PCE of 14.28%, which is smaller in comparison to FAPbI3 (44.46%) and MAPbI3 (20.24%).

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