Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.680
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Arterioscler Thromb Vasc Biol ; 44(7): 1584-1600, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38779855

RESUMO

BACKGROUND: Analysis of vascular networks is an essential step to unravel the mechanisms regulating the physiological and pathological organization of blood vessels. So far, most of the analyses are performed using 2-dimensional projections of 3-dimensional (3D) networks, a strategy that has several obvious shortcomings. For instance, it does not capture the true geometry of the vasculature and generates artifacts on vessel connectivity. These limitations are accepted in the field because manual analysis of 3D vascular networks is a laborious and complex process that is often prohibitive for large volumes. METHODS: To overcome these issues, we developed 3DVascNet, a deep learning-based software for automated segmentation and quantification of 3D retinal vascular networks. 3DVascNet performs segmentation based on a deep learning model, and it quantifies vascular morphometric parameters such as vessel density, branch length, vessel radius, and branching point density. We tested the performance of 3DVascNet using a large data set of 3D microscopy images of mouse retinal blood vessels. RESULTS: We demonstrated that 3DVascNet efficiently segments vascular networks in 3D and that vascular morphometric parameters capture phenotypes detected by using manual segmentation and quantification in 2 dimension. In addition, we showed that, despite being trained on retinal images, 3DVascNet has high generalization capability and successfully segments images originating from other data sets and organs. CONCLUSIONS: Overall, we present 3DVascNet, a freely available software that includes a user-friendly graphical interface for researchers with no programming experience, which will greatly facilitate the ability to study vascular networks in 3D in health and disease. Moreover, the source code of 3DVascNet is publicly available, thus it can be easily extended for the analysis of other 3D vascular networks by other users.


Assuntos
Aprendizado Profundo , Imageamento Tridimensional , Vasos Retinianos , Software , Animais , Vasos Retinianos/diagnóstico por imagem , Imageamento Tridimensional/métodos , Camundongos , Camundongos Endogâmicos C57BL , Interpretação de Imagem Assistida por Computador , Automação , Reprodutibilidade dos Testes
2.
Proc Natl Acad Sci U S A ; 119(14): e2114432119, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35349339

RESUMO

SignificanceAtomic resolution transmission electron microscopy (TEM) has opened up a new era of molecular science by providing atomic video images of dynamic motions of single organic and inorganic molecules. However, the images often look different from the images of molecular models, because these models are designed to visualize the electronic properties of the molecule instead of nuclear electrostatic potentials that are felt by the e-beam in TEM imaging. Here, we propose a molecular model that reproduces TEM images using atomic radii correlated to atomic number (Z). The model serves to provide a priori a useful idea of how a single molecule, molecular assemblies, and thin crystals of organic or inorganic materials look in TEM.


Assuntos
Elétrons , Microscopia Eletrônica , Microscopia Eletrônica de Transmissão
3.
Nano Lett ; 24(3): 836-843, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38193723

RESUMO

Tip-enhanced vibrational spectroscopy has advanced to routinely attain nanoscale spatial resolution, with tip-enhanced Raman spectroscopy even achieving atomic-scale and submolecular sensitivity. Tip-enhanced infrared spectroscopy techniques, such as nano-FTIR and AFM-IR spectroscopy, have also enabled the nanoscale chemical analysis of molecular monolayers, inorganic nanoparticles, and protein complexes. However, fundamental limits of infrared nanospectroscopy in terms of spatial resolution and sensitivity have remained elusive, calling for a quantitative understanding of the near-field interactions in infrared nanocavities. Here, we demonstrate the application of nano-FTIR spectroscopy to probe the amide-I vibration of a single protein consisting of ∼500 amino acid residues. Detection with higher tip tapping demodulation harmonics up to the seventh order leads to pronounced enhancement in the peak amplitude of the vibrational resonance, originating from sub-tip-radius geometrical effects beyond dipole approximations. This quantitative characterization of single-nanometer near-field interactions opens the path toward employing infrared vibrational spectroscopy at the subnanoscale and single-molecule levels.


Assuntos
Rádio (Anatomia) , Vibração , Microscopia de Força Atômica , Nanotecnologia/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Magn Reson Med ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38817204

RESUMO

PURPOSE: To compare MR axon radius estimation in human white matter using a multiband spiral sequence combined with field monitoring to the current state-of-the-art echo-planar imaging (EPI)-based approach. METHODS: A custom multiband spiral sequence was used for diffusion-weighted imaging at ultra-high b $$ b $$ -values. Field monitoring and higher order image reconstruction were employed to greatly reduce artifacts in spiral images. Diffusion weighting parameters were chosen to match a state-of-the art EPI-based axon radius mapping protocol. The spiral approach was compared to the EPI approach by comparing the image signal-to-noise ratio (SNR) and performing a test-retest study to assess the respective variability and repeatability of axon radius mapping. Effective axon radius estimates were compared over white matter voxels and along the left corticospinal tract. RESULTS: Increased SNR and reduced artifacts in spiral images led to reduced variability in resulting axon radius maps, especially in low-SNR regions. Test-retest variability was reduced by a factor of approximately 1.5 using the spiral approach. Reduced repeatability due to significant bias was found for some subjects in both spiral and EPI approaches, and attributed to scanner instability, pointing to a previously unknown limitation of the state-of-the-art approach. CONCLUSION: Combining spiral readouts with field monitoring improved mapping of the effective axon radius compared to the conventional EPI approach.

5.
Magn Reson Med ; 91(6): 2579-2596, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38192108

RESUMO

PURPOSE: This study aims to evaluate two distinct approaches for fiber radius estimation using diffusion-relaxation MRI data acquired in biomimetic microfiber phantoms that mimic hollow axons. The methods considered are the spherical mean power-law approach and a T2-based pore size estimation technique. THEORY AND METHODS: A general diffusion-relaxation theoretical model for the spherical mean signal from water molecules within a distribution of cylinders with varying radii was introduced, encompassing the evaluated models as particular cases. Additionally, a new numerical approach was presented for estimating effective radii (i.e., MRI-visible mean radii) from the ground truth radii distributions, not reliant on previous theoretical approximations and adaptable to various acquisition sequences. The ground truth radii were obtained from scanning electron microscope images. RESULTS: Both methods show a linear relationship between effective radii estimated from MRI data and ground-truth radii distributions, although some discrepancies were observed. The spherical mean power-law method overestimated fiber radii. Conversely, the T2-based method exhibited higher sensitivity to smaller fiber radii, but faced limitations in accurately estimating the radius in one particular phantom, possibly because of material-specific relaxation changes. CONCLUSION: The study demonstrates the feasibility of both techniques to predict pore sizes of hollow microfibers. The T2-based technique, unlike the spherical mean power-law method, does not demand ultra-high diffusion gradients, but requires calibration with known radius distributions. This research contributes to the ongoing development and evaluation of neuroimaging techniques for fiber radius estimation, highlights the advantages and limitations of both methods, and provides datasets for reproducible research.


Assuntos
Imagem de Difusão por Ressonância Magnética , Modelos Teóricos , Imagem de Difusão por Ressonância Magnética/métodos , Axônios , Microscopia , Neuroimagem
6.
Electrophoresis ; 45(11-12): 1054-1064, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38506142

RESUMO

Numerical modeling of Taylor dispersion analysis (TDA) was performed using COMSOL Multiphysics to facilitate better and faster optimization of the experimental conditions. Parameters, such as pressure, electric field, diameter, and length of capillary on the TDA conditions, were examined for particles with hydrodynamic radius (Rh) of 2.5-250 Å. The simulations were conducted using 25, 50, and 100 cm length tubes with diameters of 25, 50, and 100 µm. It was shown that particles with larger diffusion coefficients gave more accurate results at higher velocities, and in longer and wider columns; particles with smaller diffusion coefficients gave more accurate results at smaller velocities, and in shorter and thinner columns. Moreover, the effect of electric field on the validity and the applicability of TDA was studied using TDA in conjunction with capillary electrophoresis. Diffusion coefficients were obtained using a pressure and the TDA equation and compared with those obtained with a pressure in combination of an electric field for fluorescein, FD4, FD20, FD70, and FD500. We found that TDA can be used with the presence of moderate electrophoretic migration and electroosmotic flow, when appropriate conditions were met.


Assuntos
Eletroforese Capilar , Eletroforese Capilar/métodos , Simulação por Computador , Difusão , Modelos Teóricos , Eletro-Osmose/métodos , Eletricidade , Hidrodinâmica , Tamanho da Partícula , Pressão
7.
Osteoporos Int ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900165

RESUMO

Our study investigates vertebral fractures in individuals with distal radius fractures. Among 512 patients, 41.21% had vertebral fractures, predominantly in the lumbar spine. These findings highlight the importance of screening for vertebral fractures in this population, informing early intervention strategies to mitigate risks associated with osteoporosis. PURPOSE: This study's main goal was to look into the frequency, location, kind, and severity of asymptomatic vertebral fragility fractures (VFF) in people who had fractures of the fragility of the distal radius. Although VFF is frequently misdiagnosed, it is linked to higher mortality, morbidity, and hip fracture risk. The study also attempted to investigate the relationship between VFF and certain demographic and lifestyle factors, as well as FRAX data, in this patient population. METHODS: Between January, 2021, and January, 2022, individuals with low-energy distal radial fractures who presented to the emergency room of tertiary care hospital of Karachi, Pakistan, were the subject of a cross-sectional study and were 45 years of age or older except those who fitted the exclusion criteria (n = 208). The thoracic and/or lumbar spine was imaged using radiology, and information on demographics, way of life, and FRAX (Fracture Risk Assessment Tool) was gathered. Using the Genant semiquantitative approach, an impartial and blinded orthopaedist identified VF in the images and determined their severity. SPSS version 20 was used to analyse the data. RESULTS: Two hundred eleven (41.21%) of them were found to have radiographic VFF and only 12 (2.34%) of the 512 patients who were tested were getting osteoporotic therapy. The thoracic spine (32.7%), followed by the lumbar spine (43.12%), was the area most frequently afflicted. In 24.17% of the patients, multiple fractures of the thoracolumbar spine were found. The wedge form (54.5%), followed by biconcave (30.81%) and crush (14.7%), was the most prevalent VFF type. The majority of detected VFF were rated as having a 25-40% height loss (64.9%) then severe (> 40%) fractures (35.1%), according to the Genant grading method. Notably, there were no variations in smoking, drinking, BMI, or FRAX score between patients with and without VFF that were statistically significant. CONCLUSION: Based on our study's findings, it is clear that osteoporotic vertebral fragility fractures occur in almost half of individuals with distal radius fractures. The lumbar spine is notably the most affected region, predominantly with wedge fractures. Given the high prevalence of asymptomatic vertebral fragility fractures (VFF), proactive measures are necessary to mitigate associated risks. Prioritising comprehensive fall risk assessments for these patients and interventions to enhance bone mineral density and strength are crucial. Early identification of asymptomatic VFF enables timely intervention, optimising patient care and minimising the risk of complications in this vulnerable population.

8.
Osteoporos Int ; 35(2): 317-326, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37819401

RESUMO

We examined incidence rates (IR) for all distal radius fracture (DRF) events based on inpatient and outpatient data from a large statutory health insurance in Germany. Of all DRF, 56% were treated as inpatients, and thus, 44% treated as outpatients. IR were higher in women than in men. PURPOSE: Although a distal radius fracture (DRF) is one of the most common fractures in the elderly population, epidemiological data are limited. Many studies examine only hospitalized patients, do not analyze time trends, or include only small populations. In this retrospective population-based observational study, routine data on inpatient and outpatient care of persons aged ≥ 60 years insured by a large statutory health insurance in Germany were analyzed from 2014 to 2018. METHODS: DRF were identified by ICD-10 codes. All DRF events of an individual were considered with a corresponding individual washout period. Incidence rates (IR) and time trends were estimated assuming a Poisson distribution per 100,000 person-years, with 95% confidence intervals [95% CI] and age-sex standardization to the German population in 2018. Associations of calendar year, age, sex, and comorbidity with IR were examined using Poisson regression estimating incidence rate ratios (IRR) with CI. RESULTS: The study population consists of 974,332 insured individuals, with 16,557 experiencing one or more DRF events during the observation period. A total of 17,705 DRF events occurred, of which 9961 (56.3%) were hospitalized. Standardized IR were 439 [424-453] (inpatient: 240 [230-251], outpatient: 199 [189-209]) in 2014 and 438 [423-452] (inpatient: 238 [227-249], outpatient: 200 [190-210]) in 2018. Female sex, older age, and comorbidity were associated with higher IR and adjusted Poisson regression showed no significant time trend (IRR overall 0.994 [0.983-1.006]). CONCLUSION: A relevant proportion of DRF were treated in outpatient settings, so both inpatient and outpatient data are necessary for a valid estimate.


Assuntos
Fraturas do Rádio , Fraturas do Punho , Masculino , Humanos , Idoso , Feminino , Estudos Retrospectivos , Incidência , Pacientes Ambulatoriais , Pacientes Internados , Fraturas do Rádio/epidemiologia
9.
J Bone Miner Metab ; 42(2): 207-213, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418699

RESUMO

INTRODUCTION: The purpose of this study was to clarify the relationship between seasonal variation and distal radius fractures using diagnosis procedure combination data in Japan. MATERIALS AND METHODS: The participants were hospitalized patients who underwent surgical treatment for distal radius fracture as the primary injury at hospitals that introduced the diagnosis procedure combination system between April 2011 and March 2016. We obtained a summary table of the month of admission, region of residence, age at admission, and sex of the patients from the Ministry of Health, Labour and Welfare and evaluated it by month, region, age group, and sex. RESULTS: The total number of patients for the 5 years from 2011 to 2016 was 105,025. There were 29,224 male and 75,801 female participants, with a female-to-male ratio of 2.6. The mean age was 60.2 (standard deviation, 20.8) years. Distal radius fractures occurred more frequently in the winter, especially among female individuals in eastern Japan. Female participants aged ≥ 50 years tended to have a higher incidence of distal radius fracture in winter. The incidence of distal radius fracture among male participants aged 0-19 years was higher from spring to autumn. CONCLUSION: Surgically treated distal radius fractures occur frequently during the winter months among female individuals in eastern Japan or those aged ≥ 50 years and increase from school age to adolescence, especially in male individuals from spring to autumn. We should be aware of the high incidence of distal radius fractures in winter, especially in regions with snowfall and cold temperatures.


Assuntos
Fraturas do Rádio , Fraturas do Punho , Adolescente , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estações do Ano , Estudos Transversais , Fraturas do Rádio/epidemiologia , Fraturas do Rádio/cirurgia , Pacientes Internados , Japão/epidemiologia
10.
J Bone Miner Metab ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977436

RESUMO

INTRODUCTION: This study compared the 2020 incidence of fragility fractures in Sado City with those from 2004 to 2015. MATERIALS AND METHODS: Data from patients aged ≥ 60 years living in Sado City with fragility fractures in the hip, vertebral, distal radius, and proximal humerus between January 1 and December 31, 2020, were collected. We examined the number and incidence of four types of osteoporotic fractures in the older population aged ≥ 60 years living in Sado City in 2020. We compared the results with those of the 2004, 2010, and 2015 surveys, examining the temporal change and trend in the incidence of the four fracture types in this population. We investigated the use rate of anti-osteoporotic medications and the relationship between their administration and the occurrence of fragility fractures. RESULTS: The age-specific incidence of hip fractures slightly decreased from 2015. However, the incidence of the other three fractures slightly increased, although the difference was not statistically significant. The incidence of hip fractures markedly increased in the 80 s. In 2020, the percentage of patients taking anti-osteoporotic agents before the occurrence of fractures decreased to 12.4% from 14.5% in 2015; it increased from 4% in 2004 to 7.6% in 2010. CONCLUSION: The 2020 incidence of the four fractures did not decrease, and the percentage of patients receiving anti-osteoporotic agents did not increase. A higher frequency of osteoporosis treatment is necessary to reduce the incidence of fragility fractures. We recommend using anti-osteoporotic agents to prevent hip fractures among individuals in their mid-70 s and above.

11.
J Bone Miner Metab ; 42(1): 37-46, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38057601

RESUMO

INTRODUCTION: Forearm dual-energy X-ray absorptiometry (DXA) is often performed in clinics where central DXA is unavailable. Accurate bone mineral density (BMD) measurement is crucial for clinical assessment. Forearm rotation can affect BMD measurements, but this effect remains uncertain. Thus, we aimed to conduct a simulation study using CT images to clarify the effect of forearm rotation on BMD measurements. MATERIALS AND METHODS: Forearm CT images of 60 women were analyzed. BMD was measured at the total, ultra-distal (UD), mid-distal (MD), and distal 33% radius regions with the radius located at the neutral position using digitally reconstructed radiographs generated from CT images. Then, the rotation was altered from - 30° to 30° (supination set as positive) with a one-degree increment, and the percent BMD changes from the neutral position were quantified for all regions at each angle for each patient. RESULTS: The maximum mean BMD changes were 5.8%, 7.0%, 6.2%, and 7.2% for the total, UD, MD, and distal 33% radius regions, respectively. The analysis of the absolute values of the percent BMD changes from the neutral position showed that BMD changes of all patients remained within 2% when the rotation was between - 5° and 7° for the total region, between - 3° and 2° for the UD region, between - 4° and 3° for the MD region, and between - 3° and 1° for the distal 33% radius region. CONCLUSION: Subtle rotational changes affected the BMD measurement of each region. The results showed the importance of forearm positioning when measuring the distal radius BMD.


Assuntos
Antebraço , Rádio (Anatomia) , Humanos , Feminino , Antebraço/diagnóstico por imagem , Rádio (Anatomia)/diagnóstico por imagem , Densidade Óssea , Absorciometria de Fóton/métodos
12.
Nanotechnology ; 35(40)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38986446

RESUMO

In computational studies using the Lennard-Jones (LJ) potential, the widely adopted 2.5σcutoff radius effectively truncates pairwise interactions across diverse systems (Santraet al2008J. Chem. Phys.129234704, Chen and Gao 2021Friction9502-12, Bolintineanuet al2014Part. Mech.1321-56, Takahiro and Kazuhiro 2010J. Phys.: Conf. Ser.215012123, Zhouet al2016Fuel180718-26, Toxvaerd and Dyre 2011J. Chem. Phys.134081102, Toxvaerd and Dyre 2011J. Chem. Phys.134081102). Here, we assess its adequacy in determining energy barriers encountered by a Si monoatomic tip sliding on various two-dimensional (2D) monolayers, which is crucial for understanding nanoscale friction. Our findings emphasize the necessity of a cutoff radius of at least 3.5σto achieve energy barrier values exceeding 95% accuracy across all studied 2D monolayers. Specifically, 3.5σcorresponds to 12.70 Å in graphene, 12.99 Å in MoS2and 13.25 Å in MoSe2. The barrier values calculated using this cutoff support previous experiments comparing friction between different orientations of graphene and between graphene and MoS2(Almeidaet al2016Sci. Rep.631569, Zhanget al2014Sci. China57663-7). Furthermore, we demonstrate the applicability of the 3.5σcutoff for graphene on an Au substrate and bilayer graphene. Additionally, we investigate how the atomic configuration of the tip influences the energy barrier, finding a nearly threefold increase in the barrier along the zigzag direction of graphene when using a Si(001) tip composed of seven Si atoms compared to a monoatomic Si tip.

13.
Nanotechnology ; 35(28)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38593750

RESUMO

The advancement of non-Newtonian nanofluid innovation is a crucial area of research for physicists, mathematicians, manufacturers, and materials scientists. In engineering and industries, the fluid velocity caused by rotating device and nanofluid has a lot of applications such as refrigerators, chips, heat ex-changers, hybrid mechanical motors, food development, and so on. Due to the tremendous usage of the non-Newtonian nanofluid, the originality of the current study is to explore the influence of nanoparticle radii and inter-particle spacing effects on the flow characteristics of Casson methanol-based aluminium alloy (AA7072) nanofluid through a rotating disc with Joule heating and magnetic dipole. The present problem is modeled in the form of partial differential equations (PDEs), and these PDEs are converted into ordinary differential equations with the help of suitable similarity transformations. The analytical solution to the current modeled problem has been obtained by using the homotopy analysis method (HAM) and numerical solutions are obtained by employing Runge-Kutta-Fehlberg method along with shooting technique. The main purpose of the present research work is to analyze the behavior of the velocity and temperature of the nanofluid for small and large radius of the aluminium alloy (AA7072) nanoparticles and inter-particle spacing. The radial and tangential velocities are enhanced due to rising ferro-hydrodynamic interaction parameter and the skin friction force for radial and tangential directions are enhanced 10.51% and 2.16% whenh= 0.5. Also, the heat transfer rate is reduced 18.71% and 16.70% whenh= 0.5% andRp= 1.5. In fact, the present results are compared with the published results and they met good agreement.

14.
Environ Res ; 257: 119285, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38823614

RESUMO

This study focuses on the diffusion patterns of principal ore-forming elements (Pb and Zn) and associated elements (Cd, Cu, Cr, and As) in lead-zinc ore. Sampling points in upwind and downwind directions of lead-zinc ore areas at various densities (1 N/km2 - 4 N/km2) were categorized. This study analyzed the statistical relationship between the content of PTEs in the soil around lead-zinc ore and the source strength and dominant wind direction, constructed one-dimensional and two-dimensional diffusion model, and simulated the EER scope caused by PTEs. The findings indicate that: (1) concerning source strength, the content of PTEs in soils of high-density ore aggregation areas is significantly higher than in low-density ore aggregation areas. However, the impact of source strength decreases with decreasing ore grade, with a difference in Pb content of 1.71 times among principal ore-forming elements and almost consistent Cd content among associated elements. (2) Regarding the transport pathways, for most PTEs, the inverse proportion coefficients downwind are higher than upwind, approximately 1.18-3.63 times, indicating greater migration distances of PTEs downwind due to atmospheric dispersion. (3) By establishing a two-dimensional risk diffusion model, the study simulates the maximum radius of risk diffusion (r = 5.7 km), the 50% probability radius (r = 3.1 km), and the minimum radius (r = 0.8 km) based on the maximum, median, and minimum values statistically obtained from the EER. This study provides a scientific basis for implementing preventive measures for PTEs accumulation in soil within different pollution ranges. Different risk prevention and control measures should be adopted for PTEs accumulation in soil within the three ranges after cutting off pollution sources. Subsequent research should further investigate the impact and contribution of atmospheric transmission and surface runoff on the diffusion of PTEs in areas with high risk near lead-zinc ore.


Assuntos
Monitoramento Ambiental , Mineração , Poluentes do Solo , Poluentes do Solo/análise , Difusão , Solo/química , Chumbo/análise , Modelos Teóricos , Vento , Zinco/análise
15.
Bull Math Biol ; 86(8): 96, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916694

RESUMO

Human pluripotent stem cells (hPSCs) hold promise for regenerative medicine to replace essential cells that die or become dysfunctional. In some cases, these cells can be used to form clusters whose size distribution affects the growth dynamics. We develop models to predict cluster size distributions of hPSCs based on several plausible hypotheses, including (0) exponential growth, (1) surface growth, (2) Logistic growth, and (3) Gompertz growth. We use experimental data to investigate these models. A partial differential equation for the dynamics of the cluster size distribution is used to fit parameters (rates of growth, mortality, etc.). A comparison of the models using their mean squared error and the Akaike Information criterion suggests that Models 1 (surface growth) or 2 (Logistic growth) best describe the data.


Assuntos
Conceitos Matemáticos , Modelos Biológicos , Células-Tronco Pluripotentes , Humanos , Células-Tronco Pluripotentes/citologia , Proliferação de Células , Técnicas de Cultura de Células , Células Cultivadas
16.
Mol Divers ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900332

RESUMO

Leprosy, caused by Mycobacterium leprae, remains a significant global health challenge, necessitating innovative approaches to therapeutic intervention. This study employs advanced computational drug discovery techniques to identify potential inhibitors against the ML2640c protein, a key factor in the bacterium's ability to infect and persist within host cells. Utilizing a comprehensive methodology, including virtual screening, re-docking, molecular dynamics simulations, and free energy calculations, we screened a library of compounds for their interaction with ML2640c. Four compounds (24349836, 26616083, 26648979, and 26651264) demonstrated promising inhibitory potential, each exhibiting unique binding energies and interaction patterns that suggest a strong likelihood of disrupting the protein function. The study highlights the efficacy of computational methods in identifying potential therapeutic candidates, presenting compound 26616083 as a notably potent inhibitor due to its excellent binding affinity and stability. Our findings offer a foundation for future experimental validation and optimization, marking a significant step forward in the development of new treatments for leprosy. This research not only advances the fight against leprosy but also showcases the broader applicability of computational drug discovery in tackling infectious diseases.

17.
Graefes Arch Clin Exp Ophthalmol ; 262(2): 651-661, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37578514

RESUMO

PURPOSE: To investigate the effectiveness and cutoffs of axial length/corneal radius (AL/CR) ratio for myopia detection in children by age. METHODS: Totally, 21 kindergartens and schools were enrolled. Non-cycloplegic autorefraction (NCAR), axial length (AL), horizontal and vertical meridian of corneal radius (CR1, CR2), and cycloplegic autorefraction were measured. Receiver operating characteristic (ROC) curve was used to obtain the effectiveness and cutoff for myopia detection. RESULTS: Finally, 7803 participants aged 3-18 years with mean AL/CR ratio of 2.99 ± 0.16 were included. Area under the ROC curve (AUC) of AL/CR ratio for myopia detection (0.958 for AL/CR1, 0.956 for AL/CR2, 0.961 for AL/CR) was significantly larger than that of AL (0.919, all P < 0.001), while AUCs of the three were similar with different cutoffs (> 2.98, > 3.05, and > 3.02). When divided by age, the ROC curves of AL/CR ratio in 3- to 5-year-olds showed no significance or low accuracy (AUCs ≤ 0.823) in both genders. In ≥ 6-year-olds, the accuracies were promising (AUCs ≥ 0.883, all P < 0.001), the cutoffs basically increased with age (from > 2.93 in 6-year-olds to > 3.07 in 18-year-olds among girls, and from > 2.96 in 6-year-olds to > 3.07 in 18-year-olds among boys). In addition, boys presented slightly larger cutoffs than girls in all ages except for 16 and 18 years old. For children aged 3-5 years, AL/CR ratio or AL combined with NCAR increased AUC to > 0.900. CONCLUSION: AL/CR ratio provided the best prediction of myopia with age-dependent cutoff values for all but preschool children, and the cutoffs of boys were slightly larger than those of girls. For preschool children, AL/CR ratio or AL combined with NCAR is recommended to achieve satisfactory accuracy. AL/CR ratio calculated by two meridians showed similar predictive power but with different cutoffs.


Assuntos
Miopia , Refração Ocular , Pré-Escolar , Humanos , Masculino , Feminino , Adolescente , Criança , Testes Visuais , Rádio (Anatomia) , Miopia/diagnóstico , Córnea , Midriáticos
18.
Acta Anaesthesiol Scand ; 68(3): 423-429, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37932228

RESUMO

BACKGROUND: Current methods of anaesthesia used for closed reduction of distal radial fractures may be insufficient for pain relief and muscle relaxation, potentially compromising reduction quality and patient satisfaction. Peripheral nerve blocks have already been implemented for surgery of wrist fractures and may provide optimal conditions for closed reduction due to complete motor and sensory blockade of the involved nerves. However, existing literature on peripheral nerve blocks for closed reduction is sparse, and no updated systematic review or meta-analysis exists. AIMS: This protocol is developed according to the PRISMA-P statement. The systematic review and meta-analysis aim to consolidate the literature regarding the effect and harm of peripheral nerve blocks compared with other anaesthesia modalities for closed reduction of distal radius fractures in adults. METHODS: The two primary outcomes are the proportion of participants needing surgery after closed reduction and pain during closed reduction. We will only include randomised clinical trials. Two review authors will each independently screen literature, extract data, and assess risk of bias with Risk of Bias 2 Tool. Meta-analysis will be carried out with Rstudio. We will also perform a Trial Sequential Analysis. The certainty of evidence will be judged using GRADE guidelines. DISCUSSION: We will use up-to-date methodology when conducting the systematic review outlined in this protocol. The results may guide clinicians in their decision-making regarding the use of anaesthesia for closed reduction of distal radius fractures in adults.


Assuntos
Anestesia por Condução , Fraturas do Punho , Adulto , Humanos , Revisões Sistemáticas como Assunto , Metanálise como Assunto , Dor , Nervos Periféricos
19.
BMC Ophthalmol ; 24(1): 58, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326764

RESUMO

PURPOSE: To investigate a novel marker to diagnose posterior staphylomas by measuring the radius of the steepest curvature on the retinal pigment epithelium (RPE) segmentation line using optical coherence tomography (OCT). STUDY DESIGN: Retrospective Cross-sectional Study. METHODS: The authors developed a prototype software to measure the radius of curvature on the RPE segmentation line of OCT. Twelve images of 9-mm radial OCT scans were used. The radius of curvature was measured at the steepest area of the RPE segmentation line, and the macular curvature (MC) index was calculated based on its reciprocal. Based on the wide-field fundus findings, the study sample was divided into three groups: definite posterior staphyloma, no posterior staphyloma, and undetermined. The differences of MC index among the groups and the correlation between the MC index, age, and axial length were analyzed. RESULTS: The present study analyzed 268 eyes, with 54 (20.1%) with definite posterior staphyloma, 202 (75.4%) with no posterior staphyloma, and 12 (4.5%) with undetermined disease status. A maximum MC index of 37.5 was observed in the group with no posterior staphyloma, which was less than the minimum MC index of 42.7 observed in the group with definite posterior staphyloma. The MC index had strong correlations with the axial length and age in eyes with high myopia. CONCLUSIONS: Eyes with posterior staphyloma have a steeper curvature than those with radius 8.44 mm, while eyes without posterior staphyloma do not. MC index 40 (radius 8.44 mm) might act as a reference to distinguish between those with and those without posterior staphyloma.


Assuntos
Miopia Degenerativa , Doenças da Esclera , Humanos , Epitélio Pigmentado da Retina , Rádio (Anatomia) , Estudos Retrospectivos , Estudos Transversais , Miopia Degenerativa/diagnóstico , Tomografia de Coerência Óptica/métodos
20.
Clin Rehabil ; : 2692155241258296, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38815992

RESUMO

OBJECTIVE: To describe the theoretical development and structure of an occupation-based intervention for people with a surgically repaired distal radius fracture. INTERVENTION DEVELOPMENT AND RATIONALE: The Early Daily Activity (EDA) intervention uses the performance of strategically selected daily activities as the primary rehabilitative strategy. Occupation-based interventions are recommended for hand injury rehabilitation but are often poorly described and lack explicit theoretical underpinnings. The EDA-intervention was developed from exploratory research that informed the theory and structure. The theoretical principles are that daily activity performance is (i) safe within defined parameters (ii) appropriately self-determined (iii) produces high ranges and amounts of therapeutic movement, and (iv) builds psychosocial competencies. INTERVENTION DESCRIPTION: The EDA-intervention is designed to be commenced within 2 weeks of surgery. There are three key components. The first is activity-specific education to emphasise the safety, benefits, and therapeutic actions of activity performance. A set of parameters for defining safe activities is described to support education. The second component is patient-therapist collaboration to select a range of daily activities that provide a 'just-right' challenge. Collaboration occurs at regular intervals throughout the rehabilitation period to incrementally increase the challenge of activities. The third component is performance of activities at-home targeted at improving range of movement and function. NEXT STEPS: The EDA-intervention can be used by hand therapists, but it has not yet undergone effectiveness evaluation. A planned study will explore clinician readiness to adopt the EDA-intervention, inform iterative changes to the protocol and the design of feasibility and effectiveness studies.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA