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1.
Opt Express ; 32(12): 20618-20628, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859439

RESUMO

Quantum dot (QD) light-emitting diodes (QLEDs) are promising for next-generation lighting and displays. Considering the optimization design of both the QD and device structure is expected to improve the QLED's performance significantly but has rarely been reported. Here, we use the thick-shell QDs combined with a dual-hole transport layer device structure to construct a high-efficiency QLED. The optimized thick-shell QDs with CdS/CdSe/CdS/ZnS seed/spherical quantum well/shell/shell geometry exhibit a high photoluminescence quantum yield of 96% at a shell thickness of 5.9 nm. The intermediate emissive CdSe layer with coherent strain ensures defect-free growth of the thick CdS and ZnS outer shells. Based on the orthogonal solvents assisted Poly-TPD&PVK dual-hole transport layer device architecture, the champion QLED achieved a maximum external quantum efficiency of 22.5% and a maximum luminance of 259955 cd m-2, which are 1.6 and 3.7 times that of thin-shell QDs based devices with single hole transport layer, respectively. Our study provides a feasible idea for further improving the performance of QLED devices.

2.
Eur Spine J ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38671248

RESUMO

PURPOSE: This study aimed to evaluate and compare the predictive value of vertebral bone quality (VBQ) score for low BMD and osteoporosis. Furthermore, we sought to enhance diagnostic effectiveness by integrating VBQ with easily accessible patient-specific factors. METHODS: We retrospectively analyzed data from 180 patients. VBQ was obtained by preoperative MRI. Low BMD was classified as meeting the standards for either osteopenia or osteoporosis. The receiver operating characteristic curve analysis and multivariate logistic regression were used to detect the ability of variables to assess BMD. The z-test was used to compare the area under the curves of different variables. RESULTS: VBQ was more effective in identifying low BMD than osteoporosis (AUC, 0.768 vs. 0.613, p = 0.02). Elevated VBQ (OR 6.912, 95% CI 2.72-17.6) and low BMI (0.858, 0.76-0.97) were risk factors for low BMD, while the risk factor for osteoporosis was age (1.067, 1.02-1.12), not VBQ. ROC analysis showed that AUCs were 0.613 for VBQ and 0.665 for age when screening for osteoporosis. The combined variable of VBQ, sex, age, and BMI obtained by logistic regression significantly improved the efficacy of BMD screening, with an AUC of 0.824 for low BMD and 0.733 for osteoporosis. CONCLUSION: VBQ is better at detecting low BMD than identifying osteoporosis. The ability of VBQ to predict osteoporosis is limited, and a similar diagnostic efficacy can be achieved with age. Incorporating VBQ alongside demographic data enhances the efficiency of BMD assessment. With the development of artificial intelligence in medicine, this simple method is promising.

3.
J Acoust Soc Am ; 155(3): 2257-2269, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38536062

RESUMO

Transcranial ultrasound imaging assumes a growing significance in the detection and monitoring of intracranial lesions and cerebral blood flow. Accurate solution of partial differential equation (PDE) is one of the prerequisites for obtaining transcranial ultrasound wavefields. Grid-based numerical solvers such as finite difference (FD) and finite element methods have limitations including high computational costs and discretization errors. Purely data-driven methods have relatively high demands on training datasets. The fact that physics-informed neural network can only target the same model limits its application. In addition, compared to time-domain approaches, frequency-domain solutions offer advantages of reducing computational complexity and enabling stable and accurate inversions. Therefore, we introduce a framework called FD-embedded UNet (FEUNet) for solving frequency-domain transcranial ultrasound wavefields. The PDE error is calculated using the optimal 9-point FD operator, and it is integrated with the data-driven error to jointly guide the network iterations. We showcase the effectiveness of this approach through experiments involving idealized skull and brain models. FEUNet demonstrates versatility in handling various input scenarios and excels in enhancing prediction accuracy, especially with limited datasets and noisy information. Finally, we provide an overview of the advantages, limitations, and potential avenues for future research in this study.


Assuntos
Sistemas Computacionais , Cabeça , Ultrassonografia , Redes Neurais de Computação , Crânio
4.
Nano Lett ; 23(10): 4101-4110, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37183806

RESUMO

Osteoporosis is a global disease caused by abnormal overactivation of osteoclasts. The acidic environment in sealing zone of osteoclasts with H+ pumped from cytoplasm is critical to the maturation of osteoclasts. Therefore, reducing the intracellular H+ concentration can reduce the H+ secretion of osteoclasts from the source. In our study, we developed a novel nanovesicle which encapsulates Na2HPO4 with a liposome hybridizes with preosteoclast membrane (Na2HPO4@Lipo-pOCm). These nanovesicles release Na2HPO4 into the preosteoclast by targeting preosteoclasts and membrane fusion, reducing the intracellular H+ concentration, and achieve biological cascade regulation of osteoclasts through simple pH regulation. In vitro and in vivo experiments confirmed that these nanovesicles reduce mitochondrial membrane potential by decreasing intracellular H+ concentration, thereby reducing the ROS in osteoclasts as well as the expression of the upstream transcription factor FOXM1 of Acp5. In short, this nanovesicle can significantly inhibit the osteoclasts and ameliorate osteoporosis caused by OVX.


Assuntos
Osteoclastos , Osteoporose , Humanos , Concentração de Íons de Hidrogênio , Homeostase
5.
Plant J ; 111(1): 72-84, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35436372

RESUMO

High-affinity phosphate (Pi) transporters (PHTs) PHT1;1 and PHT1;4 are necessary for plant root Pi uptake especially under Pi-deficient conditions, but how their protein stability is modulated remains elusive. Here, we identified a Ttransfer DNA insertion mutant of Sorting Nexin1 (SNX1), which had more Pi content and less anthocyanin accumulation than the wild type under deficient Pi. By contrast, the snx1-2 mutant displayed higher sensitivity to exogenous arsenate in terms of seed germination and root elongation, revealing higher Pi uptake rates. Further study showed that SNX1 could co-localize and interact with PHT1;1 and PHT1;4 in vesicles and at the plasma membrane. Genetic analysis showed that increased Pi content in the snx1-2 mutant under low Pi conditions could be extensively compromised by mutating PHT1;1 in the double mutant snx1-2 pht1;1, revealing that SNX1 is epistatic to PHT1;1. In addition, SNX1 negatively controls PHT1;1 protein stability; therefore, PHT1;1 protein abundance in the plasma membrane was increased in the snx1-2 mutant compared with the wild type under either sufficient or deficient Pi. Together, our study (i) identifies SNX1 as a key modulator of the plant response to low Pi and (ii) unravels its role in the modulation of PHT1;1 protein stability, PHT1;1 accumulation at the plasma membrane, and root Pi uptake.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
6.
Plant J ; 111(1): 269-281, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35506310

RESUMO

Low phosphate (LP) in soil is a common nutrient stress that severely restricts agricultural production, but the role, if any, of the major stress phytohormone abscisic acid (ABA) in plant phosphate (Pi) starvation responses remains elusive. Here, we report that LP-induced ABA accumulation promotes Pi uptake in an ABA INSENSITIVE5 (ABI5)-dependent manner in Arabidopsis thaliana. LP significantly activated plant ABA biosynthesis, metabolism, and stress responses, suggesting a role of ABA in the plant response to Pi availability. LP-induced ABA accumulation and expression of two major high-affinity phosphate transporter genes PHOSPHATE TRANSPORTER1;1/1;4 (PHT1;1/1;4) were severely impaired in a mutant lacking BETA-GLUCOSIDASE1 (BG1), which converts conjugated ABA to active ABA, and the mutant had shorter roots and less Pi content than wild-type plants under LP conditions. Moreover, a mutant of ABI5, which encodes a central transcription factor in ABA signaling, also exhibited suppressed root elongation and had reduced Pi content under LP conditions. ABI5 facilitated Pi acquisition by activating the expression of PHT1;1 by directly binding to its promoter, while overexpression of PHT1;1 completely rescued its Pi content under LP conditions. Together, our findings illustrate a molecular mechanism by which ABA positively modulates phosphate acquisition through ABI5 in the Arabidopsis response to phosphate deficiency.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica de Plantas , Fosfatos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Biochem Biophys Res Commun ; 662: 114-118, 2023 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-37104881

RESUMO

Ectopic osteogenesis refers to the occurrence of osteoblasts in soft tissues other than bone tissue and the formation of bone tissue. The ligamentum flavum is an essential connecting structure between adjacent vertebral lamina, which participates in the formation of the vertebral canal's posterior wall and maintains the vertebral body's stability. Ossification of the ligamentum flavum (OLF) is one of the manifestations of systemic ossification of the spinal ligaments and one of the degenerative diseases related to the spine. However, there is a lack of research on the expression and biological function of Piezo1 in ligamentum flavum. Whether Piezo1 participates in the development of OLF is still unclear. The FX-5000C cell or tissue pressure culture and real-time observation and analysis system was applied to stretch ligamentum flavum cells to detect the expression of mechanical stress channel and osteogenic markers after the effect of different stretching durations. The results showed elevated expression of mechanical stress channel Piezo1 and osteogenic markers with the effect of tensile time duration. In conclusion, Piezo1 involves in intracellular osteogenic transformation signal to promote the ossification of ligamentum flavum. An approved explanatory model and further research will be required in the future.


Assuntos
Ligamento Amarelo , Ossificação Heterotópica , Humanos , Osteogênese , Ligamento Amarelo/metabolismo , Ossificação Heterotópica/metabolismo , Coluna Vertebral/metabolismo , Osso e Ossos/metabolismo , Canais Iônicos/metabolismo
8.
Biochem Biophys Res Commun ; 641: 34-41, 2023 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-36521283

RESUMO

Delayed fracture union and nonunion are common complications of fracture encountered, while Low-intensity pulsed ultrasound (LIPUS) can stimulate bone regeneration. Still, the underlying mechanism of LIPUS on bone regeneration has been poorly understood, which resulted in varied outcomes in the clinic. Therefore, figuring out the mechanism of LIPUS on bone regeneration can lay the foundation for better use of LIPUS in clinical bone regenerative therapies. In this study, we created transgenic mice to reveal the relationship between the periosteal cells' fate and the number of ciliated cells under the LIPUS stimulation. In vitro, we isolated the periosteal cell and aim to figure out the relationship between LIPUS and HDAC6-mediated ciliogenesis and find out a potential target for LIPUS-based bone regeneration strategies. The results showed that LIPUS promoted femoral bone defect regeneration and enhanced osteogenic differentiation of Prrx1+ cells. However, these pro-effects were significantly weakened when the Prrx1+ cell's primary cilia were knocked down. Besides, LIPUS stimulated the formation of Prrx1+ cells' primary cilia in the bone defect microenvironment. In vitro, the results supported that LIPUS enhanced the osteogenic differentiation of Prrx1+ cells through HDAC6-mediated ciliogenesis. In conclusion, λ LIPUS could promote the osteogenic differentiation of Prrx1+ cells to stimulate bone regeneration and inhibit the expression of HDAC6 to increase the prevalence of primary cilia in Prrx1+ cells. LIPUS could enhance the osteogenic differentiation of Prrx1+ cells mainly through HDAC6-mediated ciliogenesis.


Assuntos
Fraturas Ósseas , Osteogênese , Animais , Camundongos , Regeneração Óssea , Diferenciação Celular , Camundongos Transgênicos , Osteogênese/fisiologia , Ondas Ultrassônicas
9.
Eur J Clin Pharmacol ; 79(12): 1641-1656, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37776377

RESUMO

BACKGROUND: To investigate the effect of timing of statin administration on lipid-lowering efficacy. METHODS: Computer searches of Pubmed, Embase, Cochrane Library, and Web of Science databases from 1986 to 2023. The impact of administration time on the lipid-lowering efficacy of statin drugs was investigated. Following a series of screenings, a funnel plot was constructed to assess its symmetry, and Egger and Beggar tests were conducted using StataMP-64 to evaluate publication bias. Meta-analysis was performed using RevMan 5.3 to combine MD values. RESULTS: Fifteen papers (1352 participants) met and included the criteria. The results of the meta-analysis showed that the effect of morning and evening administration time on plasma triglycerides (TG) (P > 0.05) and plasma high-density lipoprotein cholesterol (HDL-C) (P > 0.05) was not statistically significant. There were significant reductions in total cholesterol (TC) (MD: 0.15 mmol/L, 95% CI: 0.06-0.23, P < 0.01) and low-density lipoprotein cholesterol (LDL-C) (MD: 0.10 mmol/L, 95% CI: - 0.00-0.20, P < 0.01) in the night group. According to the analysis results of the half-life of statins, only short half-life statins showed that nocturnal administration reduced LDL-C (MD: 0.21 mmol/L, 95% CI: 0.09-0.33, P < 0.01) and TC (MD: 0.32 mmol/L, 95% CI: 0.18-0.46, P < 0.01) levels and was better than morning administration. Long half-life statins did not show significant differences. In addition, the administration time of short half-life statins also showed that night administration tended to reduce TG (MD: 0.16 mmol/L, 95% CI: 0.02-0.30, P < 0.05) levels. In subgroup analysis according to clinical factors in patients aged < 55 years, there was no significant difference in the timing of administration between the two groups; the efficacy of statins in lowering lipids in patients aged ≥ 55 years was significantly different in the TC group (P < 0.01) and LDL-C group (P < 0.01). The administration time of the TC group (P < 0.05) and LDL-C group (P < 0.05) in the Americas, Europe, and Asian groups was significantly different for statins. In addition, the American group also showed that the administration time of the two groups was significantly different from the TG group (P < 0.05). CONCLUSION: The efficacy of administering short half-life statin drugs at night in reducing plasma levels of TC, LDL-C, and TG surpasses that of morning administration. However, this study did not determine the impact of timing of statin administration in patients taking long half-life statins on the efficacy of the medication. Therefore, it is recommended to consider patient adherence when. The study was registered on PROSPERO (International Prospective Register of Systematic Reviews) as CRD42022372105 (available at https://www.crd.york.ac.uk/prospero/ ).


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , LDL-Colesterol , Revisões Sistemáticas como Assunto , Triglicerídeos , Europa (Continente)
10.
Eur Spine J ; 32(7): 2588-2593, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37133764

RESUMO

OBJECTIVE: To explore the characteristics of vertebral bone quality (VBQ) scores in patients with vertebral fragility fractures, including VBQ score and single-level VBQ score, and evaluate their effectiveness as predictors. METHODS: The VBQ scores were measured using T1-weighted MRI images. VBQ scores were compared in patients with different times of previous fragility fractures. In addition, patients with fractures were matched for age and sex with patients without fractures, and VBQ scores were compared between the two groups. Finally, the predictive efficiency of VBQ scores for vertebral fragility fractures was analyzed by the receiver-operator curve (ROC). RESULTS: The average VBQ score and single-level VBQ score in patients with fractures were 3.48 ± 0.56 and 3.60 ± 0.60 and no difference among patients with different times of previous fractures. As for the age- and sex-matched patients, fracture patients had higher VBQ scores (VBQ score: 3.48 ± 0.56 vs. 2.88 ± 0.40, p < 0.001; single-level VBQ score: 3.60 ± 0.60 vs. 2.95 ± 0.44, p < 0.001). The AUCs using the VBQ score and single-level VBQ score to predict fragility fractures were 0.815 and 0.817, respectively. The optimal thresholds of the VBQ score and single-level VBQ score for predicting fragility fractures were 3.22 and 3.16, respectively. CONCLUSION: MRI­based VBQ scores are important predictors of vertebral fragility fracture but have no predictive value for the recurrence of fractures in patients with a history of fragility fractures. The VBQ score of 3.22 and single-level VBQ score of 3.16 are optimal thresholds that can be used when using lumbar MRI scans to identify individuals at high risk for fragility fractures.


Assuntos
Fraturas Ósseas , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Idoso , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética , Densidade Óssea , Fraturas por Osteoporose/diagnóstico por imagem
11.
Clin Orthop Relat Res ; 481(7): 1399-1411, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728053

RESUMO

BACKGROUND: Ankylosing spondylitis-related cervical spine fracture with neurologic impairment (ASCF-NI) is a rare but often lethal injury. Factors independently associated with survival after treatment remain poorly defined, and identifying patients who are likely to survive the injury remains challenging. QUESTIONS/PURPOSES: (1) What factors are independently associated with survival after treatment among patients with ASCF-NI? (2) Can a nomogram be developed that is sufficiently simple for clinicians to use that can identify patients who are the most likely to survive after injury? METHODS: This retrospective study was conducted based on a multi-institutional group of patients admitted and treated at one of 29 tertiary hospitals in China between March 1, 2003, and July 31, 2019. A total of 363 patients with a mean age of 53 ± 12 years were eventually included, 343 of whom were male. According to the National Household Registration Management System, 17% (61 of 363) died within 5 years of injury. Patients were treated using nonsurgical treatment or surgery, including procedures using the anterior approach, posterior approach, or combined anterior and posterior approaches. Indications for surgery included three-column injury, unstable fracture displacement, neurologic impairment or continuous progress, and intervertebral disc incarceration. By contrast, patients generally received nonsurgical treatment when they had a relatively stable fracture or medical conditions that did not tolerate surgery. Demographic, clinical, and treatment data were collected. The primary study goal was to identify which factors are independently associated with death within 5 years of injury, and the secondary goal was the development of a clinically applicable nomogram. We developed a multivariable Cox hazards regression model, and independent risk factors were defined by backward stepwise selection with the Akaike information criterion. We used these factors to create a nomogram using a multivariate Cox proportional hazards regression analysis. RESULTS: After controlling for potentially confounding variables, we found the following factors were independently associated with a lower likelihood of survival after injury: lower fracture site, more-severe peri-injury complications, poorer American Spinal Injury Association (ASIA) Impairment Scale, and treatment methods. We found that a C5 to C7 or T1 fracture (ref: C1 to C4 and 5; hazard ratio 1.7 [95% confidence interval 0.9 to 3.5]; p = 0.12), moderate peri-injury complications (ref: absence of or mild complications; HR 6.0 [95% CI 2.3 to 16.0]; p < 0.001), severe peri-injury complications (ref: absence of or mild complications; HR 30.0 [95% CI 11.5 to 78.3]; p < 0.001), ASIA Grade A (ref: ASIA Grade D; HR 2.8 [95% CI 1.1 to 7.0]; p = 0.03), anterior approach (ref: nonsurgical treatment; HR 0.5 [95% CI 0.2 to 1.0]; p = 0.04), posterior approach (ref: nonsurgical treatment; HR 0.4 [95% CI 0.2 to 0.8]; p = 0.006), and combined anterior and posterior approach (ref: nonsurgical treatment; HR 0.4 [95% CI 0.2 to 0.9]; p = 0.02) were associated with survival. Based on these factors, a nomogram was developed to predict the survival of patients with ASCF-NI after treatment. Tests revealed that the developed nomogram had good performance (C statistic of 0.91). CONCLUSION: The nomogram developed in this study will allow us to classify patients with different mortality risk levels into groups. This, coupled with the factors we identified, was independently associated with survival, and can be used to guide more appropriate treatment and care strategies for patients with ASCF-NI. LEVEL OF EVIDENCE: Level III, therapeutic study.


Assuntos
Fraturas Ósseas , Doenças do Sistema Nervoso , Fraturas da Coluna Vertebral , Espondilite Anquilosante , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Nomogramas , Espondilite Anquilosante/complicações , Espondilite Anquilosante/diagnóstico , Espondilite Anquilosante/terapia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/terapia
12.
BMC Musculoskelet Disord ; 24(1): 223, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964520

RESUMO

BACKGROUND: Hidden blood loss (HBL) is of increasing interest to spine surgeons. This retrospective study aimed to evaluate perioperative HBL and its risk factors in patients undergoing one-segment posterior circumferential decompression surgery on thoracic ossification of the posterior longitudinal ligament (T-OPLL). METHOD: We retrospectively studied 112 patients diagnosed with T-OPLL following posterior circumferential decompression surgery from August 2015 to June 2020. Patient demographics, blood loss-related parameters, surgery-related data and imaging parameters were extracted. Postoperative complications were also recorded. Pearson or Spearman correlation analysis was used to investigate the correlation between patient demographics and HBL. Multivariate linear regression analysis was performed to determine the independent risk factors associated with HBL. RESULTS: Forty-five men and 67 women were involved in this research, with an average age of 56.4 ± 10.2 years. The mean HBL was 459.6 ± 275.4 ml, accounting for 56.5% of the total blood loss. Multiple linear regression analysis showed that double-layer sign (P = 0.000), ossification occupancy ratio (OOR) > 60% (P = 0.030), age (P = 0.010), hematocrit (Hct) loss (P = 0.034), and postoperative Hct (P = 0.016) were independent risk factors for HBL. However, OPLL morphology (P = 0.319), operation time (P = 0.587), hemoglobin (Hb) loss (P = 0.644), and postoperative Hb (P = 0.952) were not significantly different from HBL. CONCLUSION: A high proportion of HBL was found after posterior circumferential decompression surgery on T-OPLL during the perioperative period, which should not be overlooked. Double-layer sign, OOR > 60%, age, Hct loss and postoperative Hct are independent risk factors for HBL.


Assuntos
Ossificação do Ligamento Longitudinal Posterior , Fusão Vertebral , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Ligamentos Longitudinais/cirurgia , Estudos Retrospectivos , Ossificação do Ligamento Longitudinal Posterior/diagnóstico por imagem , Ossificação do Ligamento Longitudinal Posterior/cirurgia , Ossificação do Ligamento Longitudinal Posterior/complicações , Osteogênese , Descompressão Cirúrgica/efeitos adversos , Descompressão Cirúrgica/métodos , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Fusão Vertebral/métodos , Fatores de Risco , Tomografia Computadorizada por Raios X , Resultado do Tratamento
13.
BMC Musculoskelet Disord ; 24(1): 747, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735402

RESUMO

PURPOSE: To explore whether combining the Hounsfield unit (HU) values and vertebral bone quality (VBQ) scores can improve the BMD assessment in patients with lumbar degenerative diseases. METHODS: The HU values were measured by CT image, and VBQ scores were calculated by lumbar MRI image. The correlations of the opportunistic imaging parameters to the lowest T-scores were analyzed. Receiver-operating characteristic curve (ROC) analysis was used to evaluate the accuracy in detecting osteoporosis. Finally, the specificity and sensitivity of different combined methods of the HU values and VBQ scores in the diagnosis of osteoporosis were compared. RESULTS: Patients with osteoporosis had the lowest HU values and the highest VBQ scores. The correlation coefficients between the VBQ scores and the T-scores were smaller than HU values (L1 HU value: 0.702; average HU value:0.700; L1 VBQ score: -0.413; VBQ score: -0.386). The areas under the curve (AUCs) of the HU values were greater than those of the VBQ scores, and the AUCs of the L1 VBQ score were similar to the VBQ score (L1 HU value: 0.850; average HU value:0.857; L1 VBQ score: 0.704; VBQ score: 0.673). When combining the two imaging parameters in series, the specificity of the detection of osteoporosis was improved (L1 HU value and L1 VBQ score: 87.3%; Average HU value and VBQ score: 85.9%). When combining the two imaging parameters in parallel, the sensitivity of the detection of osteoporosis was improved (L1 HU value or L1 VBQ score: 88.1%; Average HU value or VBQ score: 91.5%). CONCLUSIONS: Combinations of the HU values and VBQ scores could improve the diagnostic performance of osteoporosis. In addition, considering the same diagnostic performance but easier measurement, parameters at the single-segment level were recommended to assist in the diagnosis of osteoporosis.


Assuntos
Densidade Óssea , Osteoporose , Humanos , Osteoporose/diagnóstico por imagem , Diagnóstico por Imagem , Área Sob a Curva , Região Lombossacral
14.
Prospects (Paris) ; : 1-19, 2023 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-37360046

RESUMO

This research is based on an approach that looks at cross-cultural research design as a "lens" for a deeper understanding of what goes on in the classroom. The research question is how a cross-cultural study like this one can lead to identifying the cultural script of teaching and help educators reflect on their practice. In this context, Chinese lessons could be described as a case-based study of pedagogical reasoning that drives a shift from focusing on "content" to "competence". This article draws on qualitative data collected by the researchers and a cross-cultural analysis of a science lesson in an elementary school in Beijing, China. Using the Japanese educators' critiques and Chinese reviews, the article determines the cultural script of teaching science (the first research question) and the way Chinese teachers reflect on their practice through the Japanese lens (the second research question). This study exposes the importance of teachers' understanding and reflecting on their practice, technically, practically, and critically. The analysis results show how teachers learn to change their lenses, to reflect on their teaching and reconstruct their understanding about teacher professionalism through at least four basic elements: didactics, praxis, pedagogy, and theory.

15.
J Exp Bot ; 73(17): 5961-5973, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34922349

RESUMO

Phytomelatonin is a universal signal molecule that regulates plant growth and stress responses; however, only one receptor that can directly bind with and perceive melatonin signaling has been identified so far, namely AtPMTR1/CAND2 in Arabidopsis. Whether other plants contain a similar receptor and, if so, how it functions is still unknown. In this study, we identified a new phytomelatonin receptor in the monocot maize (Zea mays), and investigated its role in plant responses to osmotic and drought stress. Using homology searching, we identified a plasma membrane-localized protein, Zm00001eb214610/ZmPMTR1, with strong binding activity to melatonin as a potential phytomelatonin receptor in maize. Overexpressing ZmPMTR1 in Arabidopsis Col-0 promoted osmotic stress tolerance, and rescued osmotic stress sensitivity of the Arabidopsis cand2-1 mutant. Furthermore, ZmPMTR1 also largely rescued defects in melatonin-induced stomatal closure in the cand2-1 mutant, thereby reducing water loss rate and increasing tolerance to drought stress. In addition, we identified a maize mutant of ZmPMTR1, EMS4-06e2fl, with a point-mutation causing premature termination of protein translation, and found that this mutant had lower leaf temperatures, increased rate of water loss, and enhanced drought stress sensitivity. Thus, we present ZmPMTR1 as the first phytomelatonin receptor to be identified and examined in a monocot plant, and our results indicate that it plays an important function in the response of maize to drought stress.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Melatonina , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Melatonina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Estresse Fisiológico/genética , Água/metabolismo , Zea mays/metabolismo
16.
Eur Spine J ; 31(4): 953-962, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35217914

RESUMO

PURPOSE: We aimed to assess the global, regional, and national burdens of low back pain (LBP) from 1990 to 2019 by gender, age, and the sociodemographic index (SDI) from the Global Burden of Disease (GBD) 2019 study. METHODS: The number of incident cases, disability-adjusted life years (DALYs), age-standardized incidence rates, and age-standardized DALY rates during 1990-2019 were obtained from the GBD 2019 study. The estimated annual percentage changes (EAPCs) in the age-standardized incidence rates and age-standardized DALY rates were determined to measure the temporal trends of LBP. RESULTS: In 2019, there were an estimated 223.5 million cases of LBP and 63.7 million LBP-related DALYs worldwide. During 1990-2019, the age-standardized incidence rate [EAPC = - 0.41; 95% confidence interval (CI) - 0.46 to - 0.36] and age-standardized DALY rate decreased (EAPC = - 0.51; 95% CI - 0.56 to - 0.46) globally. The age-standardized incidence rate of LBP decreased the most in low-middle SDI regions. The age-standardized incidence rate of LBP decreased the most in South Asia (EAPC, - 1.51), East Asia (EAPC, - 0.68), and Australasia (EAPC, - 0.26). The incidence in male subjects was lower than that in female subjects. The largest decreases in the age-standardized incidence rate and age-standardized DALY rate of LBP were observed in India, and China. CONCLUSIONS: The global age-standardized incidence rate and age-standardized DALY rate of LBP showed a downward trend, especially in East and South Asia. In addition, a heavier burden of LBP was observed in older and female populations.


Assuntos
Dor Lombar , Idoso , China , Feminino , Carga Global da Doença , Saúde Global , Humanos , Incidência , Dor Lombar/epidemiologia , Masculino , Anos de Vida Ajustados por Qualidade de Vida
17.
BMC Musculoskelet Disord ; 23(1): 994, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36401228

RESUMO

OBJECTIVE: The objective of this study was to explore the morphological characteristics of paraspinal muscles in young patients with unilateral neurological symptoms of lumbar disc herniation. METHODS: This study retrospectively analyzed young patients aged 18-40 years who were hospitalized for lumbar disc herniation in our hospital from June 2017 to June 2020. Data on sex, age, body mass index (BMI), subcutaneous fat tissue thickness (SFTT) at the L1-L2 level, duration of symptoms, degree of lumbar disc herniation, visual analog scale (VAS) for the lower back, Mo-fi-disc score, relative cross-sectional area (RCAS) of the paravertebral muscles (psoas major [PM], multifidus [MF], and erector spinae [ES]), and degree of fat infiltration (DFF) of the paravertebral muscles were collected. The VAS was used to evaluate the intensity of low back pain. Patients with VAS-back >4 points were defined as the low back pain group, and patients with ≤4 points were defined as the control group. The demographic characteristics, as well as the bilateral and ipsilateral paravertebral muscles, of the two groups were compared and analyzed. RESULT: A total of 129 patients were included in this study (52 patients in the LBP group and 77 patients in the control group). There were no significant differences in sex, BMI, or Pfirrmann grade of lumbar disc herniation between the two groups (P > 0.05). The age of the LBP group (33.58 ± 2.98 years) was greater than that of the control group (24.13 ± 2.15 years) (P = 0.002), and the SFTT at the L1-L2 level (13.5 ± 7.14 mm) was higher than that of the control group (7.75 ± 6.31 mm) (P < 0.05). Moreover, the duration of symptoms (9.15 ± 0.31 months) was longer than that of the control group (3.72 ± 0.48 months) (P < 0.05), and the Mo-fi-disc score (8.41 ± 3.16) was higher than that of the control group (5.53 ± 2.85) (P < 0.05). At L3/4 and L5/S1, there was no significant difference in the RCSA and DFF of the bilateral and ipsilateral paraspinal muscles between the LBP group and the control group. At L4/5, there was no significant difference in the RCSA and DFF of the paraspinal muscles on either side in the LBP group (P > 0.05). In the control group, the RCSA of the MF muscle on the diseased side was smaller than that on the normal side (P < 0.05), and the DFF of the MF muscle on the diseased side was larger than that on the normal side (P < 0.05). In addition, there was no significant difference in the ES and PM muscles on both sides (P > 0.05). At L4/5, the RCSA of the MF muscle on the normal side was significantly smaller in the LBP group than in the control group (P < 0.05), and the DFF of the MF muscle on the normal side was significantly larger in the LBP group than in the control group (P < 0.05). There was no significant difference in the ES and PM muscles on the same side between the two groups (P > 0.05). CONCLUSION: In young patients with unilateral neurological symptoms of lumbar disc herniation, symmetrical atrophy of the bilateral MF muscle is more prone to causing low back pain. Older age, higher SFTT at the L1-L2 levels, longer symptom duration, higher Mo-fi-di score, and greater muscle atrophy on the normal side of the MF increased the incidence of low back pain in young patients with unilateral lumbar disc herniation.


Assuntos
Deslocamento do Disco Intervertebral , Dor Lombar , Humanos , Músculos Paraespinais/diagnóstico por imagem , Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Dor Lombar/etiologia , Estudos Retrospectivos , Imageamento por Ressonância Magnética
18.
Anim Biotechnol ; 33(7): 1480-1491, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33847240

RESUMO

The purpose of this study was to investigate the role of urea-N recycling, rumen bacterial community, and rumen epithelial gene expression in nitrogen utilization of calves. Here, 12 Holstein calves were divided into two dietary treatments: a high-protein diet (HP, 173 g/kg), and a low-protein diet (LP, 125 g/kg). Urea-N kinetics was evaluated using urea-15N15N isotope labeling method. Gene expression in rumen epithelium and liver, bacterial diversity, and metabolites in rumen were characterized using transcriptomic, Illumina HiSeq-based 16S rRNA, and LC/QTOF-MS-based metabolomics, respectively. We demonstrated that the bone weight, dressing percentage, and nitrogen utilization efficiency (NUE) increased in calves fed HP compared with LP. The urea synthesized, eliminated in urine, and return to ornithine cycle were higher in calves fed HP than LP, while the urea-N reused for anabolism were the opposite. Differentially expressed genes participated in amino acid metabolism and molecular transport in rumen epithelium. The increased abundance of bacteria and metabolites involved in protein and/or amino acid metabolism reflected the larger protein utilization in rumen of calves fed HP. In conclusion, the urea-N recycling could not fully compensate for the reduced NUE caused by N deficiency. Rumen bacteria and rumen epithelial metabolism contribute to improving NUE of calves.


Assuntos
Dieta , Rúmen , Animais , Bovinos , Rúmen/metabolismo , RNA Ribossômico 16S/metabolismo , Dieta/veterinária , Ureia/metabolismo , Bactérias/genética , Nitrogênio/metabolismo , Aminoácidos/metabolismo , Ração Animal
19.
Int Orthop ; 46(5): 1095-1100, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35106669

RESUMO

PURPOSE: This study was to explore the clinical correlation between osteoporosis thoracolumbar vertebral compression fracture (thoracolumbar OVCF) and lumbar spondylolisthesis (LS). METHODS: In total, 208 patients with thoracolumbar OVCF (fracture group) and 250 elderly patients with osteoporosis (non-fracture group) were retrospectively analyzed. The incidence of LS was compared between the two groups. At the same time, 75 cases of elderly patients with osteoporosis were selected, including 25 patients with isthmic spondylolisthesis (IS group), 25 patients with degenerative spondylolisthesis (DS group), and 25 patients without LS (non-LS group). All patients underwent full-length spine anteroposterior and lateral X-ray, and the spinal pelvic imaging parameters were collected for comparison. RESULTS: The incidence of LS in the fracture group (10.1%, 21/208) was significantly higher than that in the non-fracture group (4.8%, 12/250); the difference was statistically significant (χ2 = 4.763, P = 0.029). The incidence of trauma in the fracture group (51.0%, 106/208) was significantly higher than that in the non-fracture group (13.6%, 34/250); the difference was statistically significant (χ2 = 74.673, P = 0.000). The LS (OR = 2.273, 95% CI = 1.030-5.017, P = 0.042) and trauma (OR = 6.622, 95% CI = 4.203-10.432, P = 0.000) were independently associated with thoracolumbar OVCF. There were significant differences in pelvic incidence (PI), sacral slope (SS), lumbar lordosis (LL), thoracolumbar kyphosis (TLK), and thoracic kyphosis (TK) among the IS, DS, and non-LS groups (P < 0.05). Among them, PI, SS, LL, TLK, and TK of the IS group and the DS group were significantly higher than those of the non-LS group (P < 0.05). CONCLUSIONS: Patients with LS are more likely to suffer from OVCF in the future, and LS is one of the important risk factors for secondary OVCF.


Assuntos
Fraturas por Compressão , Cifose , Lordose , Osteoporose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Espondilolistese , Idoso , Fraturas por Compressão/complicações , Fraturas por Compressão/diagnóstico por imagem , Humanos , Cifose/complicações , Cifose/diagnóstico por imagem , Lordose/complicações , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/lesões , Osteoporose/complicações , Fraturas por Osteoporose/complicações , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/epidemiologia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/epidemiologia , Espondilolistese/complicações , Espondilolistese/diagnóstico por imagem
20.
Med Sci Monit ; 27: e929417, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33517342

RESUMO

BACKGROUND The aim of this study was to verify whether the combined classification of increased signal intensity (ISI) on magnetic resonance imaging is more closely related to surgical outcomes than signal quality changes or signal longitudinal extent changes alone and to evaluate whether the combined classification ISI method could be used to predict surgical outcomes in cervical spondylotic myelopathy. MATERIAL AND METHODS Eighty-four patients (61 men and 23 women) who underwent surgery for cervical spondylotic myelopathy were included in this retrospective study. The patterns of ISI were classified into 3 categories based on (1) the quality of ISI into Grade 0: none, Grade 1: faint (fuzzy), and Grade 2: intense (sharp); (2) the longitudinal extent of ISI into none, focal, and multisegmental; and (3) the combined classification of the quality and longitudinal extent into Type 1 (none/none), Type 2 (focal/faint), Type 3 (focal/intense), Type 4 (multisegmental/faint), and Type 5 (multisegmental/intense). The multifactorial effects of variables were studied. A stepwise regression analysis was performed to verify whether this combined classification could predict outcome. RESULTS Of the 3 categories, the combined classification type of ISI was most closely related to recovery rate. Stepwise regression analysis confirmed the significance of combined classification of ISI as a predictor for surgical outcome. CONCLUSIONS A combined classification of ISI is more closely related to surgical outcomes than either signal quality changes or signal longitudinal extent changes alone and it could be used as a meaningful indicator for predicting surgical outcomes. We recommend further studies to confirm this finding.


Assuntos
Doenças da Medula Espinal/classificação , Doenças da Medula Espinal/diagnóstico por imagem , Espondilose/cirurgia , Adulto , Idoso , Vértebras Cervicais/cirurgia , China , Descompressão Cirúrgica/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Doenças da Medula Espinal/cirurgia , Espondilose/diagnóstico por imagem , Resultado do Tratamento
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