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1.
Ecol Lett ; 27(1): e14358, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38288867

RESUMO

Beyond abiotic conditions, do population dynamics mostly depend on a species' direct predators, preys and conspecifics? Or can indirect feedback that ripples across the whole community be equally important? Determining where ecological communities sit on the spectrum between these two characterizations requires a metric able to capture the difference between them. Here we show that the spectral radius of a community's interaction matrix provides such a metric, thus a measure of ecological collectivity, which is accessible from imperfect knowledge of biotic interactions and related to observable signatures. This measure of collectivity integrates existing approaches to complexity, interaction structure and indirect interactions. Our work thus provides an original perspective on the question of to what degree communities are more than loose collections of species or simple interaction motifs and explains when pragmatic reductionist approaches ought to suffice or fail when applied to ecological communities.


Assuntos
Biota , Modelos Biológicos , Dinâmica Populacional , Ecossistema
2.
Magn Reson Med ; 92(4): 1348-1362, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38818623

RESUMO

PURPOSE: The J-difference edited γ-aminobutyric acid (GABA) signal is contaminated by other co-edited signals-the largest of which originates from co-edited macromolecules (MMs)-and is consequently often reported as "GABA+." MM signals are broader and less well-characterized than the metabolites, and are commonly approximated using a Gaussian model parameterization. Experimentally measured MM signals are a consensus-recommended alternative to parameterized modeling; however, they are relatively under-studied in the context of edited MRS. METHODS: To address this limitation in the literature, we have acquired GABA-edited MEGA-PRESS data with pre-inversion to null metabolite signals in 13 healthy controls. An experimental MM basis function was derived from the mean across subjects. We further derived a new parameterization of the MM signals from the experimental data, using multiple Gaussians to accurately represent their observed asymmetry. The previous single-Gaussian parameterization, mean experimental MM spectrum and new multi-Gaussian parameterization were compared in a three-way analysis of a public MEGA-PRESS dataset of 61 healthy participants. RESULTS: Both the experimental MMs and the multi-Gaussian parameterization exhibited reduced fit residuals compared to the single-Gaussian approach (p = 0.034 and p = 0.031, respectively), suggesting they better represent the underlying data than the single-Gaussian parameterization. Furthermore, both experimentally derived models estimated larger MM fractional contribution to the GABA+ signal for the experimental MMs (58%) and multi-Gaussian parameterization (58%), compared to the single-Gaussian approach (50%). CONCLUSIONS: Our results indicate that single-Gaussian parameterization of edited MM signals is insufficient and that both experimentally derived GABA+ spectra and their parameterized replicas improve the modeling of GABA+ spectra.


Assuntos
Substâncias Macromoleculares , Ácido gama-Aminobutírico , Ácido gama-Aminobutírico/metabolismo , Humanos , Feminino , Adulto , Masculino , Substâncias Macromoleculares/metabolismo , Espectroscopia de Ressonância Magnética , Distribuição Normal , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Modelos Lineares , Algoritmos , Adulto Jovem
3.
Magn Reson Med ; 91(2): 431-442, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37876339

RESUMO

PURPOSE: To compare the respective ability of PRESS and sLASER to reveal biological relationships, using age as a validation covariate at 3 T. METHODS: MRS data were acquired from 102 healthy volunteers using PRESS and sLASER in centrum semiovale and posterior cingulate cortex (PCC). Acquisition parameters included TR/TE = 2000/30 ms, 96 transients, and 2048 datapoints sampled at 2 kHz. Spectra were analyzed using Osprey. SNR, FWHM linewidth of total creatine, and metabolite concentrations were extracted. A linear model was used to compare SNR and linewidth. Paired t-tests were used to assess differences in metabolite measurements between PRESS and sLASER. Correlations were used to evaluate the relationship between PRESS and sLASER metabolite estimates, as well as the strength of each metabolite-age relationship. Coefficients of variation were calculated to assess inter-subject variability in each metabolite measurement. RESULTS: SNR and linewidth were significantly higher (p < 0.01) for sLASER than PRESS in PCC. Paired t-tests showed significant differences between PRESS and sLASER in most metabolite measurements. PRESS-sLASER measurements were significantly correlated (p < 0.05) for most metabolites. Metabolite-age relationships were consistently identified using both methods. Similar coefficients of variation were observed for most metabolites. CONCLUSION: The study results suggest strong agreement between PRESS and sLASER in identifying relationships between brain metabolites and age in centrum semiovale and PCC data acquired at 3 T. sLASER is technically desirable due to the reduced chemical shift displacement artifact; however, PRESS performed similarly in homogeneous brain regions at clinical field strength.


Assuntos
Encéfalo , Corpo Caloso , Humanos , Espectroscopia de Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Creatina/metabolismo , Modelos Lineares
4.
NMR Biomed ; 37(3): e5065, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37897259

RESUMO

A recurring issue in functional neuroimaging is how to link task-driven haemodynamic blood oxygen level dependent functional MRI (BOLD-fMRI) responses to underlying neurochemistry at the synaptic level. Glutamate and γ-aminobutyric acid (GABA), the major excitatory and inhibitory neurotransmitters respectively, are typically measured with MRS sequences separately from fMRI, in the absence of a task. The present study aims to resolve this disconnect, developing acquisition and processing techniques to simultaneously assess GABA, glutamate and glutamine (Glx) and BOLD in relation to a cognitive task, at 3 T. Healthy subjects (N = 81) performed a cognitive task (Eriksen flanker), which was presented visually in a task-OFF, task-ON block design, with individual event onset timing jittered with respect to the MRS readout. fMRS data were acquired from the medial anterior cingulate cortex during task performance, using an adapted MEGA-PRESS implementation incorporating unsuppressed water-reference signals at a regular interval. These allowed for continuous assessment of BOLD activation, through T2 *-related changes in water linewidth. BOLD-fMRI data were additionally acquired. A novel linear model was used to extract modelled metabolite spectra associated with discrete functional stimuli, building on well established processing and quantification tools. Behavioural outcomes from the flanker task, and activation patterns from the BOLD-fMRI sequence, were as expected from the literature. BOLD response assessed through fMRS showed a significant correlation with fMRI, specific to the fMRS-targeted region of interest; fMRS-assessed BOLD additionally correlated with lengthening of response time in the incongruent flanker condition. While no significant task-related changes were observed for GABA+, a significant increase in measured Glx levels (~8.8%) was found between task-OFF and task-ON periods. These findings verify the efficacy of our protocol and analysis pipelines for the simultaneous assessment of metabolite dynamics and BOLD. As well as establishing a robust basis for further work using these techniques, we also identify a number of clear directions for further refinement in future studies.


Assuntos
Ácido Glutâmico , Imageamento por Ressonância Magnética , Humanos , Ácido Glutâmico/metabolismo , Imageamento por Ressonância Magnética/métodos , Glutamina/metabolismo , Ácido gama-Aminobutírico/metabolismo , Cognição , Água
5.
NMR Biomed ; 37(4): e5076, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38091628

RESUMO

Literature values vary widely for within-subject test-retest reproducibility of gamma-aminobutyric acid (GABA) measured with edited magnetic resonance spectroscopy (MRS). Reasons for this variation remain unclear. Here, we tested whether three acquisition parameters-(1) sequence complexity (two-experiment MEscher-GArwood Point RESolved Spectroscopy [MEGA-PRESS] vs. four-experiment Hadamard Encoding and Reconstruction of MEGA-Edited Spectroscopy [HERMES]); (2) editing pulse duration (14 vs. 20 ms); and (3) scanner frequency drift (interleaved water referencing [IWR] turned ON vs. OFF)-and two linear combination modeling variations-(1) three different coedited macromolecule models (called "1to1GABA", "1to1GABAsoft", and "3to2MM" in the Osprey software package); and (2) 0.55- versus 0.4-ppm spline baseline knot spacing-affected the within-subject coefficient of variation of GABA + macromolecules (GABA+). We collected edited MRS data from the dorsal anterior cingulate cortex from 20 participants (mean age: 30.8 ± 9.5 years; 10 males). Test and retest scans were separated by removing the participant from the scanner for 5-10 min. Each acquisition consisted of two MEGA-PRESS and two HERMES sequences with editing pulse durations of 14 and 20 ms (referred to here as MEGA-14, MEGA-20, HERMES-14, and HERMES-20; all TE = 80 ms, 224 averages). We identified the best test-retest reproducibility following postprocessing with a composite model of the 0.9- and 3-ppm macromolecules ("3to2MM"); this model performed particularly well for the HERMES data. Furthermore, sparser (0.55- compared with 0.4-ppm) spline baseline knot spacing yielded generally better test-retest reproducibility for GABA+. Replicating our prior results, linear combination modeling in Osprey compared with simple peak fitting in Gannet resulted in substantially better test-retest reproducibility. However, reproducibility did not consistently differ for MEGA-PRESS compared with HERMES, for 14- compared with 20-ms editing pulses, or for IWR-ON versus IWR-OFF. These results highlight the importance of model selection for edited MRS studies of GABA+, particularly for clinical studies that focus on individual patient differences in GABA+ or changes following an intervention.


Assuntos
Encéfalo , Ácido gama-Aminobutírico , Masculino , Humanos , Adulto Jovem , Adulto , Reprodutibilidade dos Testes , Espectroscopia de Ressonância Magnética/métodos , Imagens de Fantasmas , Substâncias Macromoleculares/metabolismo , Encéfalo/metabolismo
6.
NMR Biomed ; : e5215, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39051103

RESUMO

The use of sequential proton magnetic resonance spectroscopy (MRS) to follow glutamate and gamma-aminobutyric acid (GABA) changes during functional task-based paradigms, functional MRS (fMRS), has increased. This technique has been used to investigate GABA dynamics during both sensory and behavioural tasks, usually with long 'block design' paradigms. Recently, there has been an increase in interest in the use of short stimuli and 'event-related' tasks. While changes in glutamate can be readily followed by collecting multiple individual transients (or shots), measurement of GABA, especially at 3 T, is usually performed using editing techniques like Mescher-Garwood point-resolved spectroscopy (MEGA-PRESS), which by its nature is a dual shot approach. This poses problems when considering an event-related experiment, where it is unclear when GABA may change, or how this may affect the individual subspectra of the MEGA-PRESS acquisition. To address this issue, MEGA-PRESS data were simulated to reflect the effect of a transient change in GABA concentration due to a short event-related stimulus. The change in GABA was simulated for both the ON and OFF subspectra, and the effect of three different conditions (increase only during ON acquisition, increase during OFF acquisition and increase across both) on the corresponding edited GABA spectrum was modelled. Results show that a transient increase in GABA that only occurs during the ON subspectral acquisition, while not changing the results much from when GABA is changed across both conditions, will give a much larger change in the edited GABA spectrum than a transient increase that occurs only during the OFF subspectral acquisition. These results suggest that researchers should think carefully about the design of any event-related fMRS studies using MEGA-PRESS, as well as the analysis of other functional paradigms where transient changes in GABA may be expected. Experimental design considerations are therefore discussed, and suggestions are made.

7.
Chemistry ; 30(42): e202401581, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38771299

RESUMO

Transition metal carbides find widespread use throughout industry due to their high strength and resilience under extreme conditions. However, they remain largely limited to compounds formed from the early d-block elements, since the mid-to-late transition metals do not form thermodynamically stable carbides. We report here the high-pressure bulk synthesis of large single crystals of a novel metastable manganese carbide compound, MnCx (P63/mmc), which adopts the anti-NiAs-type structure with significant substoichiometry at the carbon sites. We demonstrate how synthesis pressure modulates the carbon loading, with ~40 % occupancy being achieved at 9.9 GPa.

8.
J Magn Reson Imaging ; 59(3): 964-975, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37401726

RESUMO

BACKGROUND: Deep learning-based methods have been successfully applied to MRI image registration. However, there is a lack of deep learning-based registration methods for magnetic resonance spectroscopy (MRS) spectral registration (SR). PURPOSE: To investigate a convolutional neural network-based SR (CNN-SR) approach for simultaneous frequency-and-phase correction (FPC) of single-voxel Meshcher-Garwood point-resolved spectroscopy (MEGA-PRESS) MRS data. STUDY TYPE: Retrospective. SUBJECTS: Forty thousand simulated MEGA-PRESS datasets generated from FID Appliance (FID-A) were used and split into the following: 32,000/4000/4000 for training/validation/testing. A 101 MEGA-PRESS medial parietal lobe data retrieved from the Big GABA were used as the in vivo datasets. FIELD STRENGTH/SEQUENCE: 3T, MEGA-PRESS. ASSESSMENT: Evaluation of frequency and phase offsets mean absolute errors were performed for the simulation dataset. Evaluation of the choline interval variance was performed for the in vivo dataset. The magnitudes of the offsets introduced were -20 to 20 Hz and -90° to 90° and were uniformly distributed for the simulation dataset at different signal-to-noise ratio (SNR) levels. For the in vivo dataset, different additional magnitudes of offsets were introduced: small offsets (0-5 Hz; 0-20°), medium offsets (5-10 Hz; 20-45°), and large offsets (10-20 Hz; 45-90°). STATISTICAL TESTS: Two-tailed paired t-tests for model performances in the simulation and in vivo datasets were used and a P-value <0.05 was considered statistically significant. RESULTS: CNN-SR model was capable of correcting frequency offsets (0.014 ± 0.010 Hz at SNR 20 and 0.058 ± 0.050 Hz at SNR 2.5 with line broadening) and phase offsets (0.104 ± 0.076° at SNR 20 and 0.416 ± 0.317° at SNR 2.5 with line broadening). Using in vivo datasets, CNN-SR achieved the best performance without (0.000055 ± 0.000054) and with different magnitudes of additional frequency and phase offsets (i.e., 0.000062 ± 0.000068 at small, -0.000033 ± 0.000023 at medium, 0.000067 ± 0.000102 at large) applied. DATA CONCLUSION: The proposed CNN-SR method is an efficient and accurate approach for simultaneous FPC of single-voxel MEGA-PRESS MRS data. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.


Assuntos
Aprendizado Profundo , Humanos , Estudos Retrospectivos , Ácido gama-Aminobutírico/química , Espectroscopia de Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos
9.
BJU Int ; 133(6): 725-732, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38316611

RESUMO

OBJECTIVES: To evaluate the advantages of adding acupuncture to standard postoperative pain management for open radical prostatectomy (RP). MATERIALS AND METHODS: A randomized controlled trial (1:1:1) comparing routine postoperative analgesic care (control [CON]) vs the addition of press tack needle acupuncture (ACU) or press tack placebo acupressure (SHAM) for pain management after open RP was performed. A total of 126 patients were enrolled between February 2020 and April 2021. After open RP, the CON group received standard postoperative analgesia, the ACU group received long-term acupuncture with press tacks at specific points (P-6, Shenmen and SP-6) along with standard analgesia, and the SHAM group received placebo press tacks at the same acupuncture points alongside standard analgesia. The primary endpoint was postoperative pain measured on a numeric rating scale, the NRS-11, calculated as the area under the curve. The cumulative use of routine postoperative analgesics, time to first defaecation, and quality of life were analysed using the Kruskal-Wallis rank sum test, Fisher's exact test, and Pearson's chi-squared test. RESULTS: The ACU group reported significantly less postoperative pain compared to the SHAM (P = 0.007) and CON groups (P = 0.02). There were no significant difference in median (interquartile range) cumulative pain medication usage, time to first defaecation (CON: 37 [33, 44] h; SHAM: 37 [33, 42] h; ACU: 37 [33, 41] h; P > 0.9), or health status at discharge (EuroQol five-dimension, five-level general health assessment questionnaire: CON: 70 [65-83]; SHAM: 70 [60-80]; ACU: 70 [50-80]). CONCLUSION: Incorporating acupuncture into postoperative pain management can improve patient postoperative outcomes.


Assuntos
Dor Pós-Operatória , Prostatectomia , Humanos , Prostatectomia/efeitos adversos , Prostatectomia/métodos , Masculino , Dor Pós-Operatória/etiologia , Pessoa de Meia-Idade , Idoso , Terapia por Acupuntura/métodos , Medição da Dor , Manejo da Dor/métodos , Neoplasias da Próstata/cirurgia , Analgesia por Acupuntura/métodos , Qualidade de Vida
10.
Exp Brain Res ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136723

RESUMO

This study aimed to utilize the nonnegative matrix factorization (NNMF) algorithm for muscle synergy analysis, extracting synergy structures and muscle weightings and mining biomarkers reflecting changes in muscle fatigue from these synergy structures. A leg press exercise to induce fatigue was performed by 11 participants. Surface electromyography (sEMG) data from seven muscles, electrocardiography (ECG) data, Borg CR-10 scale scores, and the z-axis acceleration of the weight block were simultaneously collected. Three indices were derived from the synergy structures: activation phase difference, coactivation area, and coactivation time. The indicators were further validated for single-leg landing. Differences in heart rate (HR) and heart rate variability (HRV) were observed across different fatigue levels, with varying degrees of disparity. The median frequency (MDF) exhibited a consistent decline in the primary working muscle groups. Significant differences were noted in activation phase difference, coactivation area, and coactivation time before and after fatigue onset. Moreover, a significant correlation was found between the activation phase difference and the coactivation area with fatigue intensity. The further application of single-leg landing demonstrated the effectiveness of the coactivation area. These indices can serve as biomarkers reflecting simultaneous alterations in the central nervous system and muscle activity post-exertion.

11.
CNS Spectr ; 29(2): 85-86, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-37605924

RESUMO

Data on minority group physicians from diverse racial/ethnic backgrounds is sparse and not reported by PG metrics at the national level. While PG metrics typically concentrate on the individual, patterns and trends are clearly discernible at the group level and comparison of groups to capture patterns may yield results hitherto unknown. One could even envisage using AI to capture any trends, differences, and comparative figures to build databases for the future. It is time to retool PG surveys to fit the modern U.S. healthcare workforce and be inclusive, and not selective at the individual level.


Assuntos
Diversidade, Equidade, Inclusão , Satisfação do Paciente , Humanos , Inquéritos e Questionários
12.
Cereb Cortex ; 33(12): 7386-7394, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-36843135

RESUMO

Gamma-aminobutyric acid (GABA) and glutamatergic system perturbations following premature birth may explain neurodevelopmental deficits in the absence of structural brain injury. Using GABA-edited spectroscopy (MEscher-GArwood Point Resolved Spectroscopy [MEGA-PRESS] on 3 T MRI), we have described in-vivo brain GABA+ (+macromolecules) and Glx (glutamate + glutamine) concentrations in term-born infants. We report previously unavailable comparative data on in-vivo GABA+ and Glx concentrations in the cerebellum, the right basal ganglia, and the right frontal lobe of preterm-born infants without structural brain injury. Seventy-five preterm-born (gestational age 27.8 ± 2.9 weeks) and 48 term-born (39.6 ± 0.9 weeks) infants yielded reliable MEGA-PRESS spectra acquired at post-menstrual age (PMA) of 40.2 ± 2.3 and 43.0 ± 2 weeks, respectively. GABA+ (median 2.44 institutional units [i.u.]) concentrations were highest in the cerebellum and Glx higher in the cerebellum (5.73 i.u.) and basal ganglia (5.16 i.u.), with lowest concentrations in the frontal lobe. Metabolite concentrations correlated positively with advancing PMA and postnatal age at MRI (Spearman's rho 0.2-0.6). Basal ganglia Glx and NAA, and frontal GABA+ and NAA concentrations were lower in preterm compared with term infants. Moderate preterm infants had lower metabolite concentrations than term and extreme preterm infants. Our findings emphasize the impact of premature extra-uterine stimuli on GABA-glutamate system development and may serve as early biomarkers of neurodevelopmental deficits.


Assuntos
Lesões Encefálicas , Nascimento Prematuro , Lactente , Gravidez , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Ácido Glutâmico/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Ácido gama-Aminobutírico/metabolismo
13.
BMC Vet Res ; 20(1): 222, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38783269

RESUMO

BACKGROUND: Biomedtrix BFX® cementless total hip replacement (THR) requires the use of femoral broaches to prepare a press-fit envelope within the femur for subsequent stem insertion. Current broaches contain teeth that crush and remove cancellous bone; however, they are not particularly well-suited for broaching sclerotic (corticalized) cancellous bone. In this study, three tooth designs [Control, TG1 (additional V-grooves), TG2 (diamond tooth pattern)] were evaluated with a quasi-static testing protocol and polyurethane test blocks simulating normal and sclerotic bone. To mimic clinical broaching, a series of five sequential broach insertions were used to determine cumulative broaching energy (J) and peak loads during broach insertion. To determine the effect of broach tooth design on THR stem insertion, a BFX® stem was inserted into prepared test blocks and insertion and subsidence energy and peak loads were determined. RESULTS: Broach tooth design led to significant differences in broaching energy and peak broaching loads in test blocks of both densities. In low density test blocks, TG1 required the lowest cumulative broaching energy (10.76 ±0.29 J), followed by Control (12.18 ±1.20 J) and TG2 (16.66 ±0.78 J) broaches. In high density test blocks, TG1 required the lowest cumulative broaching energy (32.60 ±2.54 J) as compared to Control (33.25 ±2.16 J) and TG2 (59.97 ±3.07 J).  During stem insertion and subsidence testing, stem insertion energy for high density test blocks prepared with Control broaches was 14.53 ± 0.81 J, which was significantly lower than blocks prepared with TG1 (22.53 ± 1.04 J) or TG2 (19.38 ± 3.00 J) broaches. For stem subsidence testing in high density blocks, TG1 prepared blocks required the highest amount of energy to undergo subsidence (14.49 ± 0.49 J), which was significantly greater than test blocks prepared with Control (11.09 ±0.09 J) or TG2 (12.57 ± 0.81 J) broaches. CONCLUSIONS: The additional V-grooves in TG1 broaches demonstrated improved broaching performance while also generating press-fit envelopes that were more resistant to stem insertion and subsidence. TG1 broaches may prove useful in the clinical setting; however additional studies that more closely simulate clinical broach impaction are necessary prior to making widespread changes to THR broaches.


Assuntos
Artroplastia de Quadril , Artroplastia de Quadril/veterinária , Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/métodos , Animais , Cães/cirurgia , Prótese de Quadril/veterinária , Fenômenos Biomecânicos , Fêmur/cirurgia
14.
Graefes Arch Clin Exp Ophthalmol ; 262(1): 191-201, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37624385

RESUMO

PURPOSE: To investigate the postoperative intraocular pressure (IOP) control and identify the factors associated with failure of initial Ex-PRESS surgery in patients with open-angle glaucoma for 3 years. METHODS: A total of 79 patients with medically uncontrolled open-angle glaucoma (55 normal-tension glaucoma and 24 primary open-angle glaucoma) were enrolled. All patients underwent Ex-PRESS implantation (including combined cataract surgery). The outcome measure was the survival rate using life table analysis, the failure was defined as IOP of > 18 mmHg (criterion A), > 15 mmHg (criterion B) or > 12 mmHg (criterion C) and/or IOP reduction of < 20% from baseline (each criterion) without any glaucoma medications. The Cox proportional hazards model was used to identify risk factors for IOP management defined as the above criterion.  RESULTS: The mean preoperative IOP was 19.3 ± 5.8 mmHg. At 36 months, the mean IOP was 11.8 ± 3.6 mmHg with a mean IOP change of 7.5 mmHg (reduction rate 39.0%). The cumulative probability of success was 58% (95%CI: 42-64%) (criterion A), 48% (95%CI: 37-59%) (criterion B) and 30% (95%CI: 20-40%) (criterion C). In multivariate analyses, factors that predicted poor IOP control included the intervention of bleb needling after 6 months after the surgery (HR: 2.43; 95%CI: 1.35-4.37; P = 0.032). Transient hypotony was observed in 4 patients. CONCLUSION: The implementation of bleb needling after Ex-PRESS surgery in the late postoperative period was suggested to be the main risk factor for achieving lower IOP.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma de Ângulo Aberto , Glaucoma , Glaucoma de Baixa Tensão , Trabeculectomia , Humanos , Pressão Intraocular , Glaucoma de Ângulo Aberto/cirurgia , Glaucoma de Ângulo Aberto/complicações , Seguimentos , Glaucoma/cirurgia , Glaucoma de Baixa Tensão/diagnóstico , Glaucoma de Baixa Tensão/cirurgia , Glaucoma de Baixa Tensão/complicações , Drenagem , Resultado do Tratamento
15.
Scand J Med Sci Sports ; 34(1): e14507, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37787096

RESUMO

Concurrent training has been postulated as an appropriate time-efficient strategy to improve physical fitness, yet whether the exercise-induced adaptations are similar in men and women is unknown. An unblinded randomized controlled trial was conducted to investigate sex-specific dose-response effects of a 24-week supervised concurrent exercise training program on cardiorespiratory fitness and muscular strength in young adults. One hundred and forty-four sedentary adults aged 18-25 years were assigned to either (i) a control group (n = 54), (ii) a moderate intensity exercise group (MOD-EX, n = 46), or (iii) a vigorous intensity exercise group (VIG-EX, n = 44) by unrestricted randomization. Cardiorespiratory fitness (VO2max ), hand grip strength, and one-repetition maximum of leg press and bench press were evaluated at baseline and after the intervention. A total of 102 participants finished the intervention (Control, n = 36; 52% women, MOD-EX, n = 37; 70% women, and VIG-EX, n = 36; 72% women). In men, VO2max significantly increased in the MOD-EX (~8%) compared with the control group and in the VIG-EX group after the intervention (~6.5%). In women, VO2max increased in the MOD-EX and VIG-EX groups (~5.5%) compared with the control group after the intervention. There was a significant increment of leg press in the MOD-EX (~15.5%) and VIG-EX (~18%) groups compared with the control group (~1%) in women. A 24-week supervised concurrent exercise was effective at improving cardiorespiratory fitness and lower body limbs muscular strength in young women-independently of the predetermined intensity-while only at moderate intensity improved cardiorespiratory fitness in men.


Assuntos
Aptidão Cardiorrespiratória , Masculino , Humanos , Feminino , Adulto Jovem , Adolescente , Adulto , Aptidão Cardiorrespiratória/fisiologia , Força da Mão , Aptidão Física , Força Muscular/fisiologia , Terapia por Exercício
16.
Scand J Public Health ; : 14034948231178879, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454563

RESUMO

AIMS: Press freedom around the globe has deteriorated over the past decade, especially during the COVID-19 pandemic. This paper explores the effect of press freedom, as a cornerstone of democracy, on life expectancy. METHODS: Exploring cross-country data, we use the ordinary least square method to estimate the association between press freedom and life expectancy. In addition, we adopt three novel instrumental variables to explore the causal relationship. RESULTS: Our estimations indicate that a freer press leads to higher life expectancy, and the effect exists independently of the level of democracy. In addition, the effect of continuous exposure to press freedom is stronger than sporadic free press status. The results are robust to measurement errors, influential outliers, and country-specific heterogeneity. CONCLUSIONS: This study reveals the fundamental role of press freedom in promoting public health that was previously underexplored. Therefore, enhancing freedom of expression can be an effective tool to address three of the United Nations Millennium Development Goals, that is, reduce under-five mortality, improve maternal health, and combat HIV/AIDS.JEL:I1 H7 D02.

17.
Eur Heart J ; 44(40): 4220-4229, 2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37165687

RESUMO

Large-scale clinical trials are essential in cardiology and require rapid, accurate publication, and dissemination. Whereas conference presentations, press releases, and social media disseminate information quickly and often receive considerable coverage by mainstream and healthcare media, they lack detail, may emphasize selected data, and can be open to misinterpretation. Preprint servers speed access to research manuscripts while awaiting acceptance for publication by a journal, but these articles are not formally peer-reviewed and sometimes overstate the findings. Publication of trial results in a major journal is very demanding but the use of existing checklists can help accelerate the process. In case of rejection, procedures such as easing formatting requirements and possibly carrying over peer-review to other journals could speed resubmission. Secondary publications can help maximize benefits from clinical trials; publications of secondary endpoints and subgroup analyses further define treatment effects and the patient populations most likely to benefit. These rely on data access, and although data sharing is becoming more common, many challenges remain. Beyond publication in medical journals, there is a need for wider knowledge dissemination to maximize impact on clinical practice. This might be facilitated through plain language summary publications. Social media, websites, mainstream news outlets, and other publications, although not peer-reviewed, are important sources of medical information for both the public and for clinicians. This underscores the importance of ensuring that the information is understandable, accessible, balanced, and trustworthy. This report is based on discussions held on December 2021, at the 18th Global Cardiovascular Clinical Trialists meeting, involving a panel of editors of some of the top medical journals, as well as members of the lay press, industry, and clinical trialists.

18.
Public Health ; 228: 112-118, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354580

RESUMO

OBJECTIVES: This study aims to assess COVID-related communication by Swiss public health institutions (PHI) as well as the challenges they faced in implementing their communication strategies. STUDY DESIGN: This study uses a two-part mixed methods design, combining automated content analysis of press releases by PHI and semi-structured interviews with PHI communication experts. METHODS: The automated content analysis uses natural language processing techniques to measure semantic themes and linguistic properties of 1882 press releases from national and regional PHI during the first year of the COVID-19 pandemic. The semi-structured interviews with 25 communication experts from key PHI explore the challenges faced in implementing their communication strategies. RESULTS: The content analysis reveals key themes in press releases, including non-pharmaceutical interventions, quarantine, testing, contact tracing, hospital situations, and the pandemic's impact on the economy. The linguistic measures indicated a decrease in complexity and readability over time, with no significant differences between national and regional PHI. Interviews revealed challenges arising from organizational structures, the multi-systemic nature of the pandemic, and from expectations of the public. CONCLUSIONS: The study highlights the importance of agility in public health communication and the need for efficient coordination within and between PHI. Organizational structures should be adapted to allow for more agile modes of operation during crises. Policymakers should clarify roles and responsibilities of different actors in public health frameworks to ensure streamlined communication. Understanding the communication efforts and challenges faced by PHI during the pandemic helps preparing for future health crises and improve public health communication practices.


Assuntos
COVID-19 , Comunicação em Saúde , Humanos , Saúde Pública , Pandemias , Suíça , Comunicação
19.
Proc Jpn Acad Ser B Phys Biol Sci ; 100(3): 149-164, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38311394

RESUMO

Since the large-volume press with a double-stage multianvil system was created by the late Professor Naoto Kawai, this apparatus (Kawai-type multianvil apparatus or KMA) has been developed for higher-pressure generation, in situ X-ray and neutron observations, deformation experiments, measurements of physical properties, synthesis of high-pressure phases, etc., utilizing its large sample volume and capacity in stable and homogeneous high temperature generation compared to those of competitive diamond anvil cells. These advancements in KMA technology have been made primarily by Japanese scientists and engineers, which yielded a wealth of new experimental data on phase transitions, melting relations, and physical characteristics of minerals and rocks, leading to significant constraints on the structures, chemical compositions, and dynamics of the deep Earth. KMA technology has also been used for synthesis of novel functional materials such as nano-polycrystalline diamond and transparent nano-ceramics, opening a new research field of ultrahigh-pressure materials science.


Assuntos
Diamante , Tecnologia , Diamante/química , Fenômenos Físicos
20.
J Shoulder Elbow Surg ; 33(8): 1755-1761, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38242528

RESUMO

BACKGROUND: Although cementation of humeral stems has long been considered the gold standard for anatomic shoulder arthroplasty (aTSA), cementless, or press-fit, fixation offers a relatively cheaper and less demanding alternative, particularly in the setting of a revision procedure. However, this approach has been accompanied by concerns of implant loosening and high rates of radiolucency. In the present study, we performed a propensity-matched comparison of clinical and patient-reported outcomes between cemented and cementless fixation techniques for aTSA. We hypothesized that cemented fixation of the humeral component would have significantly better implant survival while providing comparable functional outcomes at final follow-up. METHODS: This study was a retrospective comparison of 50 shoulders undergoing aTSA: 25 using cemented humeral fixation vs. 25 using press-fit humeral fixation. Patients in the 2 groups were propensity matched according to age, sex, and preoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score. Primary outcome measures included range of motion (ROM) (forward elevation, external rotation, internal rotation), patient-reported outcomes (ASES, Simple Shoulder Test [SST], visual analog scale [VAS]), and implant survival. RESULTS: At baseline, the 2 fixation groups were similar in regard to age, sex, body mass index, preoperative ASES score, and surgical indication. Mean follow-up was 11.7 ± 4.95 years in the cemented cohort and 9.13 ± 3.77 years in the press-fit cohort (P = .045). Both groups demonstrated significant improvements postoperatively in all included ROM and patient-reported outcomes. However, press-fit patients reported significantly better VAS, ASES, and SST scores. Mean VAS pain score was 1.1 ± 1.8 in press-fit patients and 3.2 ± 3.0 in cemented patients (P = .005). The mean ASES score was 87.7 ± 12.4 in press-fit patients and 69.5 ± 22.7 in cemented patients (P = .002). Lastly, the mean SST score was 9.8 ± 3.1 in press-fit patients and 7.7 ± 3.7 in cemented patients (P = .040). Both fixation techniques provided lasting implant survivorship with only a single revision operation in each of the cohorts. CONCLUSION: Herein, we provide a propensity-matched, long-term comparison of patients receiving anatomic shoulder arthroplasty stratified according to humeral stem fixation technique. The results of this analysis illustrate that both types of humeral fixation techniques yield durable and significant improvements in shoulder function with similar rates of survival at 10 years of follow-up.


Assuntos
Artroplastia do Ombro , Desenho de Prótese , Amplitude de Movimento Articular , Humanos , Masculino , Feminino , Estudos Retrospectivos , Idoso , Seguimentos , Pessoa de Meia-Idade , Artroplastia do Ombro/métodos , Prótese de Ombro , Cimentação , Cimentos Ósseos , Úmero/cirurgia , Pontuação de Propensão , Falha de Prótese , Articulação do Ombro/cirurgia , Resultado do Tratamento
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