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1.
Neuroimage ; 297: 120733, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39033788

RESUMO

Emotions are fundamental to social interaction and deeply intertwined with interpersonal dynamics, especially in romantic relationships. Although the neural basis of interaction processes in romance has been widely explored, the underlying emotions and the connection between relationship quality and neural synchronization remain less understood. Our study employed EEG hyperscanning during a non-interactive video-watching paradigm to compare the emotional coordination between romantic couples and close friends. Couples showed significantly greater behavioral and prefrontal alpha synchronization than friends. Notably, couples with low relationship quality required heightened neural synchronization to maintain robust behavioral synchronization. Further support vector machine analysis underscores the crucial role of prefrontal activity in differentiating couples from friends. In summary, our research addresses gaps concerning how intrinsic emotions linked to relationship quality influence neural and behavioral synchronization by investigating a natural non-interactive context, thereby advancing our understanding of the neural mechanisms underlying emotional coordination in romantic relationships.


Assuntos
Eletroencefalografia , Emoções , Amigos , Relações Interpessoais , Humanos , Masculino , Amigos/psicologia , Emoções/fisiologia , Feminino , Adulto Jovem , Adulto , Córtex Pré-Frontal/fisiologia , Interação Social
2.
J Cell Physiol ; 237(5): 2357-2373, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35288937

RESUMO

Polypyrimidine tract-binding protein (PTB), as a member of the heterogeneous nuclear ribonucleoprotein family, functions by rapidly shuttling between the nucleus and the cytoplasm. PTB is involved in the alternative splicing of pre-messenger RNA (mRNA) and almost all steps of mRNA metabolism. PTB regulation is organ-specific; brain- or muscle-specific microRNAs and long noncoding RNAs partially contribute to regulating PTB, thereby modulating many physiological and pathological processes, such as embryonic development, cell development, spermatogenesis, and neuron growth and differentiation. Previous studies have shown that PTB knockout can inhibit tumorigenesis and development. The knockout of PTB in glial cells can be reprogrammed into functional neurons, which shows great promise in the field of nerve regeneration but is controversial.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Processamento Alternativo/genética , Ribonucleoproteínas Nucleares Heterogêneas/genética , Neurônios/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , RNA Mensageiro/genética
3.
J Cell Physiol ; 236(12): 8099-8109, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34101182

RESUMO

The generation of patient-specific induced pluripotent stem cells (iPSCs) holds significant implications for replacement therapy in treating optic neuropathies such as glaucoma. Stem-cell-based therapy targeted at replacing and replenishing retinal ganglion cells is progressing at a fast pace. However, clinical application necessitates an efficient and robust approach for cell manufacturing. Here, we examine whether the embryo body derived from human peripheral blood-derived iPSC can localize into the host retina and differentiate into retinal ganglion cells after transplantation into a glaucoma injury model. Human peripheral blood T cells were isolated and reprogrammed into an induced pluripotent stem cell (TiPSC) line using Sendai virus transduction carrying transcription factors Sox2, Klf4, c-Myc, and Oct4. TiPSCs were differentiated into RGC using neural basal culture. For in vivo studies, embryo bodies derived from TiPSCs (TiPSC-EB) were injected into the vitreous cavity of N-Methyl-d-aspartic acid (NMDA)-treated mice 2 weeks before sacrifice and retinal dissection. Induced pluripotent stem cells generated from human peripheral blood T cells display stem cell morphology and pluripotency markers. Furthermore, RGC-like cells differentiated from TiPSC exhibit extending axons and RGC marker TUJ1. When transplanted intravitreally into NMDA-treated mice, embryo bodies derived from TiPSC survived, migrated, and incorporated into the retina's GCL layer. In addition, TiPSC-EB transplants were able to differentiate into TUJ1 positive RGC-like cells. Retinal ganglion cells can be differentiated using human peripheral blood cells derived iPSC. Transplantation of embryo body derived from TiPSCs into a glaucoma mouse model could incorporate into host GCL and differentiate into RGC-like cells.


Assuntos
Células Sanguíneas/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Retina/citologia , Células Ganglionares da Retina/metabolismo , Transplante de Células-Tronco , Animais , Diferenciação Celular/fisiologia , Modelos Animais de Doenças , Humanos , Camundongos , N-Metilaspartato/metabolismo , Neurogênese/fisiologia , Transplante de Células-Tronco/métodos
4.
BMC Ophthalmol ; 21(1): 217, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001054

RESUMO

BACKGROUND: To investigate the feasibility and efficacy of posterior pole retinotomy to treat recurrent macular hole retinal detachment (MHRD) in highly myopic patients. METHODS: We performed a retrospective study and reviewed the medical records in our hospital between January 1, 2016 and December 31, 2018. Highly myopic patients who received posterior pole retinotomy with silicone oil tamponade for their recurrent MHRD after pars plana vitrectomy were included in the analysis. Postoperative retinal reattachment, best-corrected visual acuity (BCVA), macular hole closure, and complications were evaluated. RESULTS: There were 11 patients (11 eyes) included in this study. All retinas were reattached. Silicone oil was successfully removed from all eyes 1.5-3 months after the surgery. Macular holes were completely closed in three eyes and remained flat open in eight eyes. The BCVA of all eyes improved significantly at 12 months after surgery (logarithm of the minimal angle of resolution, pre vs. postoperatively, 1.87 ± 0.44 vs. 1.15 ± 0.24, P < 0.05). None of the patients had complications such as endophthalmitis, fundus hemorrhage, retinal redetachment, and proliferative vitreoretinopathy. CONCLUSION: Posterior pole retinotomy is a safe and effective surgery to treat recurrent MHRD after pars plana vitrectomy in highly myopic patients.


Assuntos
Descolamento Retiniano , Perfurações Retinianas , Humanos , Projetos Piloto , Descolamento Retiniano/etiologia , Descolamento Retiniano/cirurgia , Perfurações Retinianas/cirurgia , Estudos Retrospectivos , Acuidade Visual , Vitrectomia
5.
Ann Surg Oncol ; 27(11): 4296-4306, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32729045

RESUMO

BACKGROUND: The aim of this work is to combine radiological and pathological information of tumor to develop a signature for pretreatment prediction of discrepancies of pathological response at several centers and restage patients with locally advanced rectal cancer (LARC) for individualized treatment planning. PATIENTS AND METHODS: A total of 981 consecutive patients with evaluation of response according to tumor regression grade (TRG) who received nCRT were retrospectively recruited from four hospitals (primary cohort and external validation cohort 1-3); both pretreatment multiparametric MRI (mp-MRI) and whole slide image (WSI) of biopsy specimens were available for each patient. Quantitative image features were extracted from mp-MRI and WSI and used to construct a radiopathomics signature (RPS) powered by an artificial-intelligence model. Models based on mp-MRI or WSI alone were also constructed for comparison. RESULTS: The RPS showed overall accuracy of 79.66-87.66% in validation cohorts. The areas under the curve of RPS at specific response grades were 0.98 (TRG0), 0.93 (≤ TRG1), and 0.84 (≤ TRG2). RPS at each grade of pathological response revealed significant improvement compared with both signatures constructed without combining multiscale tumor information (P < 0.01). Moreover, RPS showed relevance to distinct probabilities of overall survival and disease-free survival in patients with LARC who underwent nCRT (P < 0.05). CONCLUSIONS: The results of this study suggest that radiopathomics, combining both radiological information of the whole tumor and pathological information of local lesions from biopsy, could potentially predict discrepancies of pathological response prior to nCRT for better treatment planning.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias Retais , Humanos , Terapia Neoadjuvante , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Estudos Retrospectivos , Resultado do Tratamento
6.
Optom Vis Sci ; 97(7): 489-495, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32697555

RESUMO

SIGNIFICANCE: Investigation of the mechanism and the role of melanopsin in lens-induced myopia is necessary to find out potential targets in the prevention of myopia development. PURPOSE: We aimed to study the effect and mechanism of retinal melanopsin on lens-induced myopia in guinea pigs, as well as the interactions between melanopsin and other myopic regulation neurotransmitters such as dopamine and melatonin, and to explore the possible role of melanopsin in the prevention of myopia development. METHODS: Twenty-day-old tricolor guinea pigs were randomly divided into four groups: control group, defocus group, defocus + AA92593 group, and defocus + dimethyl sulfoxide (DMSO) group. The defocus eyes wore -6.00 D lens. In the defocus + AA92593 group, the vitreous cavities were injected with melanopsin antagonist AA92593. In the defocus + DMSO group, the vitreous cavities were injected with 5% DMSO as the administration control. The expression of retinal melanopsin protein was measured with immunofluorescence staining and Western blot. The content of dopamine and melatonin in the retina was determined by the high-performance liquid chromatography electrochemical method. RESULTS: Compared with the defocus group, intravitreal injection of AA92593 resulted in increased axial length of the defocus eyes (defocus, 8.05 ± 0.09 mm; defocus + AA92593, 8.15 ± 0.11 mm; P = .008), lower refractive degree (defocus, -1.98 ± 0.82 D; defocus + AA92593, -2.59 ± 0.97 D; P = .05), decreased relative expression of retinal melanopsin protein (defocus, 0.67 ± 0.11; defocus + AA92593, 0.20 ± 0.06; P < .0001), and increased melatonin content in the defocus eyes (defocus, 0.38 ± 0.09 ng/mg; defocus + AA92593, 0.55 ± 0.13 ng/mg; P = .01), but it had no obvious effect on dopamine content (defocus, 0.64 ± 0.18 ng/mg; defocus + AA9259, 0.61 ± 0.17 ng/mg; P > .99). The melatonin content of retina in the defocus + AA92593 group was correlated with refractive error (Pearson correlation coefficient = -0.68, P = .006) and eye axis length (Pearson correlation coefficient = 0.74, P = .02). CONCLUSIONS: Retinal melanopsin has inhibitory effect on lens-induced myopia development in guinea pigs, and such effect may be related to retinal melatonin.


Assuntos
Lentes de Contato/efeitos adversos , Miopia/metabolismo , Células Ganglionares da Retina/metabolismo , Opsinas de Bastonetes/metabolismo , Animais , Comprimento Axial do Olho , Western Blotting , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Dopamina/metabolismo , Técnica Indireta de Fluorescência para Anticorpo , Cobaias , Melatonina/metabolismo , Miopia/etiologia , Opsinas de Bastonetes/antagonistas & inibidores
7.
Ann Surg Oncol ; 26(6): 1676-1684, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30887373

RESUMO

OBJECTIVE: The aim of this study was to investigate whether pretherapeutic, multiparametric magnetic resonance imaging (MRI) radiomic features can be used for predicting non-response to neoadjuvant therapy in patients with locally advanced rectal cancer (LARC). METHODS: We retrospectively enrolled 425 patients with LARC [allocated in a 3:1 ratio to a primary (n = 318) or validation (n = 107) cohort] who received neoadjuvant therapy before surgery. All patients underwent T1-weighted, T2-weighted, diffusion-weighted, and contrast-enhanced T1-weighted MRI scans before receiving neoadjuvant therapy. We extracted 2424 radiomic features from the pretherapeutic, multiparametric MR images of each patient. The Wilcoxon rank-sum test, Spearman correlation analysis, and least absolute shrinkage and selection operator regression were successively performed for feature selection, whereupon a multiparametric MRI-based radiomic model was established by means of multivariate logistic regression analysis. This feature selection and multivariate logistic regression analysis was also performed on all single-modality MRI data to establish four single-modality radiomic models. The performance of the five radiomic models was evaluated by receiver operating characteristic (ROC) curve analysis in both cohorts. RESULTS: The multiparametric, MRI-based radiomic model based on 16 features showed good predictive performance in both the primary (p < 0.01) and validation (p < 0.05) cohorts, and performed better than all single-modality models. The area under the ROC curve of this multiparametric MRI-based radiomic model achieved a score of 0.822 (95% CI 0.752-0.891). CONCLUSIONS: We demonstrated that pretherapeutic, multiparametric MRI radiomic features have potential in predicting non-response to neoadjuvant therapy in patients with LARC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Terapia Neoadjuvante/métodos , Neoplasias Retais/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Neoplasias Retais/tratamento farmacológico , Estudos Retrospectivos
9.
iScience ; 27(4): 109460, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38550980

RESUMO

Various energy storage systems (ESS) can be derived from the Brayton cycle, with the most representative being compressed air energy storage and pumped thermal electricity storage systems. Although some important studies on above ESS are reported, the topological structure behind those systems (i.e., derivations of the Brayton cycle) has not been studied, and the underlying thermodynamic ideas still need to be further explored. This paper first introduces the topological structure and the symmetry of ESS and their based Brayton cycles. The formation method of ESS based on paths and separation points is specified. It is found that round-trip path can form ESS directly. Then various ESS formed are compared. Finally, the synergistic effect and gain principle of thermal cycle and ESS are revealed. This work helps to reveal the intrinsic relationship between thermal cycles and ESS, understand the general laws behind ESS, and guide the combination of thermal cycles and ESS.

10.
Eur J Surg Oncol ; 50(7): 108369, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38703632

RESUMO

BACKGROUND: TNM staging is the main reference standard for prognostic prediction of colorectal cancer (CRC), but the prognosis heterogeneity of patients with the same stage is still large. This study aimed to classify the tumor microenvironment of patients with stage III CRC and quantify the classified tumor tissues based on deep learning to explore the prognostic value of the developed tumor risk signature (TRS). METHODS: A tissue classification model was developed to identify nine tissues (adipose, background, debris, lymphocytes, mucus, smooth muscle, normal mucosa, stroma, and tumor) in whole-slide images (WSIs) of stage III CRC patients. This model was used to extract tumor tissues from WSIs of 265 stage III CRC patients from The Cancer Genome Atlas and 70 stage III CRC patients from the Sixth Affiliated Hospital of Sun Yat-sen University. We used three different deep learning models for tumor feature extraction and applied a Cox model to establish the TRS. Survival analysis was conducted to explore the prognostic performance of TRS. RESULTS: The tissue classification model achieved 94.4 % accuracy in identifying nine tissue types. The TRS showed a Harrell's concordance index of 0.736, 0.716, and 0.711 in the internal training, internal validation, and external validation sets. Survival analysis showed that TRS had significant predictive ability (hazard ratio: 3.632, p = 0.03) for prognostic prediction. CONCLUSION: The TRS is an independent and significant prognostic factor for PFS of stage III CRC patients and it contributes to risk stratification of patients with different clinical stages.


Assuntos
Neoplasias Colorretais , Aprendizado Profundo , Estadiamento de Neoplasias , Microambiente Tumoral , Humanos , Neoplasias Colorretais/patologia , Prognóstico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Modelos de Riscos Proporcionais
11.
Phys Med Biol ; 69(6)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38373345

RESUMO

Objective.Generally, due to a lack of explainability, radiomics based on deep learning has been perceived as a black-box solution for radiologists. Automatic generation of diagnostic reports is a semantic approach to enhance the explanation of deep learning radiomics (DLR).Approach.In this paper, we propose a novel model called radiomics-reporting network (Radioport), which incorporates text attention. This model aims to improve the interpretability of DLR in mammographic calcification diagnosis. Firstly, it employs convolutional neural networks to extract visual features as radiomics for multi-category classification based on breast imaging reporting and data system. Then, it builds a mapping between these visual features and textual features to generate diagnostic reports, incorporating an attention module for improved clarity.Main results.To demonstrate the effectiveness of our proposed model, we conducted experiments on a breast calcification dataset comprising mammograms and diagnostic reports. The results demonstrate that our model can: (i) semantically enhance the interpretability of DLR; and, (ii) improve the readability of generated medical reports.Significance.Our interpretable textual model can explicitly simulate the mammographic calcification diagnosis process.


Assuntos
Aprendizado Profundo , Radiômica , Redes Neurais de Computação , Mamografia/métodos , Relatório de Pesquisa
12.
Artigo em Inglês | MEDLINE | ID: mdl-39102321

RESUMO

Visual feedback gain is a crucial factor influencing the performance of precision grasping tasks, involving multiple brain regions of the visual motor system during task execution. However, the dynamic changes in brain network during this process remain unclear. The aim of this study is to investigate the impact of changes in visual feedback gain during precision grasping on brain network dynamics. Sixteen participants performed precision grip tasks at 15% of MVC under low (0.1°), medium (1°), and high (3°) visual feedback gain conditions, with simultaneous recording of EEG and right-hand precision grip data during the tasks. Utilizing electroencephalogram (EEG) microstate analysis, multiple parameters (Duration, Occurrence, Coverage, Transition probability(TP)) were extracted to assess changes in brain network dynamics. Precision grip accuracy and stability were evaluated using root mean square error(RMSE) and coefficient of variation(CV) of grip force. Compared to low visual feedback gain, under medium/high gain, the Duration, Occurrence, and Coverage of microstates B and D increase, while those of microstates A and C decrease. The Transition probability from microstates A, C, and D to B all increase. Additionally, RMSE and CV of grip force decrease. Occurrence and Coverage of microstates B and C are negatively correlated with RMSE and CV. These findings suggest that visual feedback gain affects the brain network dynamics during precision grasping; moderate increase in visual feedback gain can enhance the accuracy and stability of grip force, whereby the increased Occurrence and Coverage of microstates B and C contribute to improved performance in precision grasping. Our results play a crucial role in better understanding the impact of visual feedback gain on the motor control of precision grasping.


Assuntos
Eletroencefalografia , Retroalimentação Sensorial , Força da Mão , Desempenho Psicomotor , Humanos , Retroalimentação Sensorial/fisiologia , Força da Mão/fisiologia , Masculino , Adulto Jovem , Adulto , Feminino , Desempenho Psicomotor/fisiologia , Rede Nervosa/fisiologia , Voluntários Saudáveis , Algoritmos , Encéfalo/fisiologia
13.
Front Hum Neurosci ; 18: 1354332, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562230

RESUMO

Stroke, also known as cerebrovascular accident, is an acute cerebrovascular disease with a high incidence, disability rate, and mortality. It can disrupt the interaction between the cerebral cortex and external muscles. Corticomuscular coherence (CMC) is a common and useful method for studying how the cerebral cortex controls muscle activity. CMC can expose functional connections between the cortex and muscle, reflecting the information flow in the motor system. Afferent feedback related to CMC can reveal these functional connections. This paper aims to investigate the factors influencing CMC in stroke patients and provide a comprehensive summary and analysis of the current research in this area. This paper begins by discussing the impact of stroke and the significance of CMC in stroke patients. It then proceeds to elaborate on the mechanism of CMC and its defining formula. Next, the impacts of various factors on CMC in stroke patients were discussed individually. Lastly, this paper addresses current challenges and future prospects for CMC.

14.
Phys Rev Lett ; 110(17): 177202, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-23679764

RESUMO

Thermally induced domain wall motion in a magnetic insulator was observed using spatiotemporally resolved polar magneto-optical Kerr effect microscopy. The following results were found: (i) the domain wall moves towards hot regime; (ii) a threshold temperature gradient (5 K/mm), i.e., a minimal temperature gradient required to induce domain wall motion; (iii) a finite domain wall velocity outside of the region with a temperature gradient, slowly decreasing as a function of distance, which is interpreted to result from the penetration of a magnonic current into the constant temperature region; and (iv) a linear dependence of the average domain wall velocity on temperature gradient, beyond a threshold thermal bias. Our observations can be qualitatively explained using a magnonic spin transfer torque mechanism, which suggests the utility of magnonic spin transfer torque for controlling magnetization dynamics.

15.
Ecotoxicol Environ Saf ; 91: 46-51, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23395389

RESUMO

The decontamination of surfaces exposed to chemical warfare agents is an interesting scientific topic. The desorption behavior of bis(2-chloroethyl) sulfide (sulfur mustard, HD) from the surface of the HD-contaminated hardened cement paste (HCP) was investigated under different weather conditions, which should provide scientific reference data for protection and decontamination projects involving HD-contaminated HCP in different conditions. The desorption of HD from the surface of HCP wafers was studied, and the effects of the purge air flow rate, water content, sorption temperature, and substrate age were investigated. HD desorption was detected from the surface of HD-contaminated HCP, but the desorption velocity was relatively slow. The desorption quantity remained within an order of magnitude throughout a time span of 36h (25°C at 200mL/min of purge air), and the amount of HD that was desorbed from each square meter of HCP surface was approximately 1.1g (25°C at 200mL/min of purge air), which was approximately 5.5 percent of the total HD that was initially applied. A higher flow rate of the purge air, increased water content, and longer substrate age of HCP all increased the HD desorption. In contrast, increased temperatures suppressed HD desorption.


Assuntos
Substâncias para a Guerra Química/química , Materiais de Construção/análise , Descontaminação , Poluentes Ambientais/química , Gás de Mostarda/química , Ar , Substâncias para a Guerra Química/análise , Poluentes Ambientais/análise , Gás de Mostarda/análise , Temperatura , Fatores de Tempo , Água/química
16.
Adv Sci (Weinh) ; 10(35): e2206932, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37939284

RESUMO

Photodynamic therapy (PDT) has been widely employed in tumor treatment due to its effectiveness. However, the tumor hypoxic microenvironment which is caused by abnormal vasculature severely limits the efficacy of PDT. Furthermore, the abnormal vasculature has been implicated in the failure of immunotherapy. In this study, a novel nanoparticle denoted as Combo-NP is introduced, composed of a biodegradable NIR II fluorescent pseudo-conjugate polymer featuring disulfide bonds within its main chain, designated as TPA-BD, and the vascular inhibitor Lenvatinib. Combo-NP exhibits dual functionality by not only inducing cytotoxic reactive oxygen species (ROS) to directly eliminate tumor cells but also eliciting immunogenic cell death (ICD). This ICD response, in turn, initiates a robust cascade of immune reactions, thereby augmenting the generation of cytotoxic T lymphocytes (CTLs). In addition, Combo-NP addresses the issue of tumor hypoxia by normalizing the tumor vasculature. This normalization process enhances the efficacy of PDT while concurrently fostering increased CTLs infiltration within the tumor microenvironment. These synergistic effects synergize to potentiate the photodynamic-immunotherapeutic properties of the nanoparticles. Furthermore, when combined with anti-programmed death-ligand 1 (PD-L1), they showcase notable inhibitory effects on tumor metastasis. The findings in this study introduce an innovative nanomedicine strategy aimed at triggering systemic anti-tumor immune responses for the treatment of Uveal melanoma.


Assuntos
Nanopartículas , Fotoquimioterapia , Inibidores de Checkpoint Imunológico , Linhagem Celular Tumoral , Polímeros/química , Imunoterapia , Nanopartículas/química
17.
Artigo em Inglês | MEDLINE | ID: mdl-37027672

RESUMO

Precise sustained force control of the fingers is important for achieving flexible hand movements. However, how neuromuscular compartments within a forearm multi-tendon muscle cooperate to achieve constant finger force remains unclear. This study aimed to investigate the coordination strategies across multiple compartments of the extensor digitorum communis (EDC) during index finger sustained constant extension. Nine subjects performed index finger extensions of 15%, 30%, and 45% maximal voluntary contractions, respectively. High-density surface electromyography signals were recorded from the EDC and then analyzed using non-negative matrix decomposition to extract activation patterns and coefficient curves of EDC compartments. The results showed two activation patterns with stable structures during all tasks: one pattern corresponding to the index finger compartment was named master pattern; whereas the other corresponding to other compartments was named auxiliary pattern. Further, the intensity and stability of their coefficient curves were assessed using the root mean square value (RMS) and coefficient of variation (CV). The RMS and CV values of the master pattern increased and decreased with time, respectively, while the corresponding values of the auxiliary pattern were both negatively correlated with the formers. These findings suggested a special coordination strategy across EDC compartments during index finger constant extension, manifesting as two compensations of the auxiliary pattern for the intensity and stability of the master pattern. The proposed method provides new insight into the synergy strategy across multiple compartments within a forearm multi-tendon during sustained isometric contraction of a single finger and a new approach for constant force control of prosthetic hands.

18.
Radiat Oncol ; 18(1): 175, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891611

RESUMO

BACKGROUND: Accurate prediction of response to neoadjuvant chemoradiotherapy (nCRT) is very important for treatment plan decision in locally advanced rectal cancer (LARC). The aim of this study was to investigate whether self-attention mechanism based multi-sequence fusion strategy applied to multiparametric magnetic resonance imaging (MRI) based deep learning or hand-crafted radiomics model construction can improve prediction of response to nCRT in LARC. METHODS: This retrospective analysis enrolled 422 consecutive patients with LARC who received nCRT before surgery at two hospitals. All patients underwent multiparametric MRI scans with three imaging sequences. Tumor regression grade (TRG) was used to assess the response of nCRT based on the resected specimen. Patients were separated into 2 groups: poor responders (TRG 2, 3) versus good responders (TRG 0, 1). A self-attention mechanism, namely channel attention, was applied to fuse the three sequence information for deep learning and radiomics models construction. For comparison, other two models without channel attention were also constructed. All models were developed in the same hospital and validated in the other hospital. RESULTS: The deep learning model with channel attention mechanism achieved area under the curves (AUCs) of 0.898 in the internal validation cohort and 0.873 in the external validation cohort, which was the best performed model in all cohorts. More importantly, both the deep learning and radiomics model that applied channel attention mechanism performed better than those without channel attention mechanism. CONCLUSIONS: The self-attention mechanism based multi-sequence fusion strategy can improve prediction of response to nCRT in LARC.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias Retais , Humanos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Estudos Retrospectivos , Terapia Neoadjuvante/métodos , Resultado do Tratamento , Quimiorradioterapia/métodos
19.
Eye (Lond) ; 37(2): 235-241, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35091707

RESUMO

BACKGROUND/OBJECTIVES: To compare the safety and efficacy of cystotome-assisted prechop phacoemulsification surgery (CAPPS) and femtosecond laser-assisted cataract surgery (FLACS) in patients with hard nucleus cataract. SUBJECTS/METHODS: Ninety-six eyes of 64 patients with grade IV hard nucleus cataract were assigned to 1 of the 2 groups (49 CAPPS and 47 FLACS). Follow-up visits were performed at 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year, and the outcome measures comprised ultrasound power, effective phacoemulsification time (EPT), corrected distance visual acuity (CDVA), endothelial cell density (ECD), corneal endothelium cell loss rate (ECL), central corneal thickness (CCT), and intraoperative and postoperative complications. RESULTS: The ultrasound power and EPT were lower in the CAPPS group (p = 0.03 and <0.0001, respectively). Patients in both groups gained better CDVA postoperatively. The ECD value decreased at each follow-up visit and did not return to the preoperative level; FLACS resulted in greater endothelial cell loss compared to CAPPS. CCT increased immediately after the surgery and decreased thereafter. The mean CCT value returned to the preoperative level 3 months postoperatively in the CAPPS group, while in the FLACS group, CCT value took 6 months to return to the preoperative level. Miosis was more likely to occur in the FLACS group. CONCLUSIONS: Due to its efficacy and cost-effectiveness, CAPPS is worth promoting and applying to clinical work in the future.


Assuntos
Extração de Catarata , Catarata , Terapia a Laser , Facoemulsificação , Humanos , Facoemulsificação/métodos , Terapia a Laser/métodos , Extração de Catarata/métodos , Catarata/complicações , Lasers
20.
Environ Technol ; 33(22-24): 2751-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23437676

RESUMO

A plant material-based air purifier (PMAP) was evaluated for odour removal. Laboratory tests were performed using two identical chambers: one treated by PMAP, and one as the control. Swine manure, hydrogen sulphide (H2S) and ammonia (NH3) were tested as odour sources. The test was also conducted in a swine barn. Air samples were taken from test chambers and two rooms in the pig barn and analysed for H2S, NH3 and odour concentrations. When treated with PMAP, the H2S concentration in the sealed chamber was subject to exponential decay, with the decay constant ranging from 0.59 to 0.70 l/h. The H2S concentration was reduced from 20 to 3 ppm in 3 h and to 0.2 ppm in 7h for H2S produced by chemical reaction, and from 0.4 to 0.02 ppm in 3 h for swine manure as the odour source. When an equal amount of ammonia solution was placed in the two test chambers, the NH3 concentration reached a peak value of 25 ppm in the chamber treated by PMAP, and 43 ppm in the control. The NH3 concentration in the treated chamber was reduced to 5 ppm in 3.5 h but stayed at 37 ppm in the control. The PMAP reduced the NH3 concentration from 38 to 10 ppm when swine manure was used as the odour source. The PMAP was capable of reducing swine odour in both laboratory and in-barn conditions. The reduction rate was at least 50%. The results from this research indicate the plant-based materials provide an alternative, environmentally friendly way for odour control. It is also shown that the mode of odour reduction by the PMAP was the removal of odour compounds, in contrast to odour masking, which occurs for most plant materials that have been used for odour control.


Assuntos
Amônia/isolamento & purificação , Sulfeto de Hidrogênio/isolamento & purificação , Esterco , Odorantes , Animais , Plantas/química , Suínos
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