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1.
Cereb Cortex ; 34(9)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39245849

RESUMEN

Definitions of human pain acknowledge at least two dimensions of pain, affective and sensory, described as separable and thus potentially differentially modifiable. Using electroencephalography, we investigated perceptual and neural changes of emotional pain modulation in healthy individuals. Painful electrical stimuli were applied after presentation of priming emotional pictures (negative, neutral, positive) and followed by pain intensity and unpleasantness ratings. We found that perceptual and neural event-related potential responses to painful stimulation were significantly modulated by emotional valence. Specifically, pain unpleasantness but not pain intensity ratings were increased when pain was preceded by negative compared to neutral or positive pictures. Amplitudes of N2 were higher when pain was preceded by neutral compared to negative and positive pictures, and P2 amplitudes were higher for negative compared to neutral and positive pictures. In addition, a hierarchical regression analysis revealed that P2 alone and not N2, predicted pain perception. Finally, source analysis showed the anterior cingulate cortex and the thalamus as main spatial clusters accounting for the neural changes in pain processing. These findings provide evidence for a separation of the sensory and affective dimensions of pain and open new perspectives for mechanisms of pain modulation.


Asunto(s)
Electroencefalografía , Emociones , Dolor , Humanos , Masculino , Femenino , Emociones/fisiología , Dolor/psicología , Dolor/fisiopatología , Adulto Joven , Adulto , Potenciales Evocados/fisiología , Percepción del Dolor/fisiología , Encéfalo/fisiología , Estimulación Eléctrica , Estimulación Luminosa/métodos , Dimensión del Dolor , Mapeo Encefálico
2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(3): 352-354, 2024 May 30.
Artículo en Chino | MEDLINE | ID: mdl-38863108

RESUMEN

The pre-research of medical device standards is of great significance for the enactment and amendment of standards. This study discusses four aspects and explores how to promote more scientific and reasonable pre-research. Based on the pre-research practice of medical device standards project, this study puts forward relevant work ideas and suggestions.


Asunto(s)
Equipos y Suministros , Equipos y Suministros/normas
3.
Curr Med Sci ; 44(2): 406-418, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38619681

RESUMEN

OBJECTIVE: Uterine corpus endometrial carcinoma (UCEC), a kind of gynecologic malignancy, poses a significant risk to women's health. The precise mechanism underlying the development of UCEC remains elusive. Zinc finger protein 554 (ZNF554), a member of the Krüppel-associated box domain zinc finger protein superfamily, was reported to be dysregulated in various illnesses, including malignant tumors. This study aimed to examine the involvement of ZNF554 in the development of UCEC. METHODS: The expression of ZNF554 in UCEC tissues and cell lines were examined by qRT-PCR and Western blot assay. Cells with stably overexpressed or knocked-down ZNF554 were established through lentivirus infection. CCK-8, wound healing, and Transwell invasion assays were employed to assess cell proliferation, migration, and invasion. Propidium iodide (PI) staining combined with fluorescence-activated cell sorting (FACS) flow cytometer was utilized to detect cell cycle distribution. qRT-PCR and Western blotting were conducted to examine relative mRNA and protein levels. Chromatin immunoprecipitation assay and luciferase reporter assay were used to explore the regulatory role of ZNF554 in RNA binding motif 5 (RBM5). RESULTS: The expression of ZNF554 was found to be reduced in both UCEC samples and cell lines. Decreased expression of ZNF554 was associated with higher tumor stage, decreased overall survival, and reduced disease-free survival in UCEC. ZNF554 overexpression suppressed cell proliferation, migration, and invasion, while also inducing cell cycle arrest. In contrast, a decrease in ZNF554 expression resulted in the opposite effect. Mechanistically, ZNF554 transcriptionally regulated RBM5, leading to the deactivation of the Wingless (WNT)/ß-catenin signaling pathway. Moreover, the findings from rescue studies demonstrated that the inhibition of RBM5 negated the impact of ZNF554 overexpression on ß-catenin and p-glycogen synthase kinase-3ß (p-GSK-3ß). Similarly, the deliberate activation of RBM5 reduced the increase in ß-catenin and p-GSK-3ß caused by the suppression of ZNF554. In vitro experiments showed that ZNF554 overexpression-induced decreases in cell proliferation and migration were counteracted by RBM5 knockdown. Additionally, when RBM5 was overexpressed, it hindered the improvements in cell proliferation and migration caused by reducing the ZNF554 levels. CONCLUSION: ZNF554 functions as a tumor suppressor in UCEC. Furthermore, ZNF554 regulates UCEC progression through the RBM5/WNT/ß-catenin signaling pathway. ZNF554 shows a promise as both a prognostic biomarker and a therapeutic target for UCEC.


Asunto(s)
Neoplasias Endometriales , Vía de Señalización Wnt , Femenino , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Proteínas de Unión al ADN/genética , Neoplasias Endometriales/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas Supresoras de Tumor/genética , Vía de Señalización Wnt/genética
4.
Anal Cell Pathol (Amst) ; 2023: 9952234, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37927399

RESUMEN

Epithelial ovarian cancer (EOC) ranks third in the incidence of gynecological malignancies. m6A methylation as RNA modification plays a crucial role in the evolution, migration, and invasion of various tumors. However, the role of m6A methylation in ovarian cancer (OC) only recently has begun to be appreciated. Therefore, we used various bioinformatic methods to screen the public GEO datasets of epithelial ovarian cancer (EOC) for m6A methylation-related regulators. We identified methyltransferase 16 (METTL16) that was dramatically downregulated in EOC as such a regulator. We also identified metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a known target lncRNA of METTL16, in these five GEO datasets. RT-qPCR and immunohistochemical staining confirmed that compared with the normal ovarian tissues and cells, METTL16 was significantly downregulated, while lncRNA MALAT1 was significantly upregulated, in 30 EOC tissues of our own validation cohorts and EOC cell lines, revealing a negative correlation between METTL16 and lncRNA MALAT1. Moreover, our analysis unveiled a correlation between downregulated METTL16 and the known adverse prognostic factors of EOC patients in our own cohorts. The CCK-8, EdU, scratch wound healing, and transwell invasion assays revealed that METTL16 significantly suppressed the proliferating, migrating, and invading abilities of OC cells. The inhibitory effects of METTL16 on the in vivo tumor growth of EOC cells were measured by subcutaneous tumor formation assay in mice. Furthermore, the RIP, RNA stability assay, western blotting, and cytoimmunofluorescence staining showed that METTL16 hindered the growth of EOC cells through promoting the degradation of MALAT1 by binding that, in turn, upregulates ß-catenin protein and promotes nuclear transport of ß-catenin protein in EOC cells. This study suggests that METTL16 acts as a tumor suppressor gene of EOC by achieving its inhibitory function on the malignant progression of EOC through the METTL16/MALAT1/ß-catenin axis that are new targets for EOC diagnosis and therapy.


Asunto(s)
Neoplasias Ováricas , ARN Largo no Codificante , Humanos , Animales , Ratones , Femenino , Carcinoma Epitelial de Ovario/genética , beta Catenina/genética , Metiltransferasas/genética , ARN Largo no Codificante/genética , Neoplasias Ováricas/genética , Cateninas , Línea Celular Tumoral , Proliferación Celular/genética
5.
Am J Cancer Res ; 13(9): 4179-4191, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37818080

RESUMEN

Ovarian cancer is one of the most lethal and drug-resistant gynecological diseases. Among the various post-transcriptional RNA modifications, N6-methyladenosine (m6A) has been implicated in several malignancies, including breast cancer. Recently, the biological significance of long noncoding RNA (lncRNA) methylation has garnered significant attention. The N6-methyladenosine (m6A) demethylase ALKBH5 (Alkylation Repair Homolog Protein 5) has been shown to promote ovarian cancer development by reducing the methylation of the lncRNA RMRP. In this study, we found that a hypoxic microenvironment induces an increase in ALKBH5 expression in ovarian cancer. Both in vitro and in vivo investigations demonstrated that ALKBH5, which is overexpressed in human ovarian cancer, promotes carcinogenesis. Furthermore, using bioinformatics analysis, we predicted interactions between ALKBH5 and lncRNAs, confirming RMRP as a potential binding lncRNA for ALKBH5. ALKBH5 was found to upregulate RMRP expression via demethylation. Knockdown of RMRP in ovarian cancer cell lines led to a decrease in cell growth and migration. Additionally, we demonstrated that the inhibition of ovarian cancer by ALKBH5 knockdown is partially mediated by RMRP suppression. In conclusion, our findings reveal a novel mechanism in which ALKBH5 promotes ovarian cancer by demethylating the lncRNA RMRP, suggesting its potential as a therapeutic target for the disease.

6.
New Phytol ; 239(5): 1754-1770, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37337822

RESUMEN

Ubiquitination is a fundamental mechanism regulating the stability of target proteins in eukaryotes; however, the regulatory mechanism in seed longevity remains unknown. Here, we report that an uncharacterized E3 ligase, ARABIDOPSIS TÓXICOS EN LEVADURA 5 (ATL5), positively regulates seed longevity by mediating the degradation of ACTIVATOR OF BASAL TRANSCRIPTION 1 (ABT1) in Arabidopsis. Seeds in which ATL5 was disrupted showed faster accelerated aging than the wild-type, while expressing ATL5 in atl5-2 basically restored the defective phenotype. ATL5 was highly expressed in the embryos of seeds, and its expression could be induced by accelerated aging. A yeast two-hybrid screen identified ABT1 as an ATL5 interacting protein, which was further confirmed by bimolecular fluorescence complementary assay and co-immunoprecipitation analysis. In vitro and in vivo assays showed that ATL5 functions as an E3 ligase and mediates the polyubiquitination and degradation of ABT1. Disruption of ATL5 diminished the degradation of translated ABT1, and the degradation could be induced by seed ageing and occurred in a proteasome-dependent manner. Furthermore, disruption of ABT1 enhanced seed longevity. Taken together, our study reveals that ATL5 promotes the polyubiquitination and degradation of the ABT1 protein posttranslationally and positively regulates seed longevity in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Longevidad , Ubiquitinación , Semillas/genética , Regulación de la Expresión Génica de las Plantas
7.
Plant J ; 113(5): 1080-1094, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36625794

RESUMEN

Seed longevity is an important trait for agriculture and the conservation of genetic resources. ß-1,3-Glucanases were first recognized as pathogenesis-related proteins involved in plant defense, but their roles in seeds are largely unknown. Here, we report a glycosylphosphatidylinositol-anchored ß-1,3-glucanase, BG14, that degrades callose in seed embryos and functions in seed longevity and dormancy in Arabidopsis. The loss of function of BG14 significantly decreased seed longevity, whereas functional reversion (RE) and overexpression (OE) lines reversed and increased the impaired phenotype, respectively. The loss of function of BG14 enhanced callose deposition in the embryos of mature seeds, confirmed by quantitative determination and the decreased callose degrading ability in bg14. The drop-and-see (DANS) assay revealed that the fluorescence signal in bg14 was significantly lower than that observed in the other three genotypes. BG14 is located on the periphery of the cell wall and can completely merge with callose at the plasmodesmata of epidermal cells. BG14 was highly expressed in developing seeds and was induced by aging and abscisic acid (ABA). The loss of function of BG14 led to a variety of phenotypes related to ABA, including reduced seed dormancy and reduced responses to treatment with ABA or pacolblltrazol, whereas OE lines showed the opposite phenotype. The reduced ABA response is because of the decreased level of ABA and the lowered expression of ABA synthesis genes in bg14. Taken together, this study demonstrated that BG14 is a bona fide BG that mediates callose degradation in the plasmodesmata of embryo cells, transcriptionally influences ABA synthesis genes in developing seeds, and positively affects seed longevity and dormancy in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Latencia en las Plantas/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Longevidad , Germinación/genética , Ácido Abscísico/metabolismo , Semillas/metabolismo , Regulación de la Expresión Génica de las Plantas
8.
Brain Connect ; 13(3): 133-142, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36082989

RESUMEN

Background: Recent neuroimaging studies on upper-limb amputation have revealed the reorganization of bilateral sensorimotor cortex after sensory deprivation, underpinning the assumption of changes in the interhemispheric connections. In the present study, using functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), we aim to explore the alterations in the interhemispheric functional and structural connectivity after upper-limb amputation. Methods: Twenty-two upper-limb amputees and 15 age- and sex-matched healthy controls were recruited for MRI scanning. The amputees were further divided into subgroups by amputation side and residual limb pain (RLP). DTI metrics of corpus callosum (CC) subregions and resting-state functional connectivity (FC) between the bilateral sensorimotor cortices were measured for each participant. Linear mixed models were carried out to investigate the relationship of interhemispheric connectivity with the amputation, amputation side, and RLP. Results: Compared with healthy controls, upper-limb amputees showed lower axial diffusivity (AD) in CC subregions II and III. Subgroup analyses showed that the dominant hand amputation induced significant microstructural changes in CC subregion III. In addition, only amputees with RLP showed decreased fractional anisotropy and AD in CC, which was also correlated with the intensity of RLP. No significant changes in interhemispheric FC were found after upper-limb amputation. Conclusion: The present study demonstrated that the interhemispheric structural connectivity rather than FC degenerated after upper-limb amputation, and the degeneration of interhemispheric structural connectivity was shown to be relevant to the amputation side and the intensity of RLP. Impact statement Neuroimaging studies have revealed the functional reorganization of bilateral sensorimotor cortex after amputation, with expanded activation from the intact hemisphere to the deprived hemisphere. Our findings indicated a degeneration of interhemispheric white matter connections in upper-limb amputees, unveiling the underlying structural basis for bilateral functional reorganization after amputation.


Asunto(s)
Imagen de Difusión Tensora , Corteza Sensoriomotora , Humanos , Imagen de Difusión Tensora/métodos , Imagen por Resonancia Magnética/métodos , Amputación Quirúrgica , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/cirugía , Extremidad Superior
10.
Front Surg ; 9: 1010027, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36406350

RESUMEN

Objective: To describe the surgical techniques and short-term outcomes for 50 cases of modified sacrospinous ligament fixation via the anterior vaginal wall path for pelvic organ prolapse. Methods: 100 patients with pelvic organ prolapse (stage III or stage IV based on POP-Q staging) from January 2018 to January 2020 were retrospectively analyzed. Among them, 50 patients received modified sacrospinous ligament fixation via the anterior vaginal wall path for pelvic organ prolapse (mSSLF group), while the other 50 patients received pelvic reconstruction using T4 mesh (T4 group). Operative time, blood loss, postoperative POP-Q score, length of the hospital stay, complications, and postoperative pain were compared between the two groups. Results: The duration of the operation in mSSLF group was (50 ± 15.2 min), which was shorter than that of the T4 group (60 ± 14.8 min) (p = 0.02). No intraoperative complications were reported from the mSSLF group, whereas one vascular injury occurred in the T4 group. In both groups, postoperative pain and painful intercourse was significantly lower in the mSSLF group than in the SSLF group (p < 0.001). The exposed mesh rate was lower than T4 group. Conclusions: The rates of intraoperative complications, postoperative pain and mesh erosion were significantly lower than those of the T4 group, but there was no significant difference in the efficacy and safety of the treatment of pelvic organ prolapse. So mSSLF may be a feasible technique to manage severe prolapse, with promising short-term efficacy and safety.

11.
Front Surg ; 9: 911553, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35923438

RESUMEN

Objective: This study aims to investigate the feasibility and short-term efficacy of single-port laparoscopic-assisted transvaginal natural cavity endoscopic sacrospinous ligament suspensions (SvNOTES). Methods: A total of 30 patients diagnosed with anterior or/and middle pelvic organ prolapse Stages III and IV underwent natural vaginal cavity (SvNOTES), and 30 patients who underwent conventional sacrospinous ligament (SSLF) were used as a control group. The operation time, blood loss, postoperative POP-Q score, length of hospital stay, and complications were compared between the two groups. Results: The operation time for SvNOTE was (60 ± 13) min, which was longer than (30 ± 15) min for SSLF (P = 0.04). However, the bleeding amount in SvNOTE was 29.44 ± 2.56, significantly lower than that in the SSLF group (80 ± 10; P = 0.02), and the postoperative hospital stay in the SvNOTE group was (4 ± 2) days, longer than (3 ± 1) days in SSLF (P = 0.02). However, there were no intraoperative complications in the SvNOTE group, whereas one ureteral injury occurred in the SSLF group; in addition, the postoperative POP-Q score was significantly better in the SvNOTE group than that in the SSLF group with increasing time (P < 0.001). Conclusion: Compared with SSLF, single-port laparoscopic sacrospinous ligament suspension via the natural vaginal cavity is visualized, greatly improving the success rate of sacrospinous ligament fixation, with less blood loss and fewer complications, arguably a safer and minimally invasive surgical approach.

12.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(3): 527-536, 2022 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-35788522

RESUMEN

The pulse amplitude of fingertip volume could be improved by selecting the vascular dense area and applying appropriate pressure above it. In view of this phenomenon, this paper used Comsol Multiphysics 5.6 (Comsol, Sweden), the finite element analysis software of multi-physical field coupling simulation, to establish the vascular tissue model of a single small artery in fingertips for simulation. Three dimensional Navier-Stokes equations were solved by finite element method, the velocity field and pressure distribution of blood were calculated, and the deformation of blood vessels and surrounding tissues was analyzed. Based on Lambert Beer's Law, the influence of the longitudinal compression displacement of the lateral light surface region and the tissue model on the light intensity signal is investigated. The results show that the light intensity signal amplitude could be increased and its peak value could be reduced by selecting the area with dense blood vessels. Applying deep pressure to the tissue increased the amplitude and peak of the signal. It is expected that the simulation results combined with the previous experimental experience could provide a feasible scheme for improving the quality of finger volume pulse signal.


Asunto(s)
Piel , Programas Informáticos , Simulación por Computador , Dedos , Análisis de Elementos Finitos
13.
J Immunol Res ; 2022: 6130806, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35733918

RESUMEN

N6-methyladenosine (m6A) RNA methylation has been determined to execute crucial functions in tumorigenesis and cancer development. WT1-associated protein (WTAP) has an important "writer" role in m6A modification, and it is also a nuclear protein that colocalizes with splicing factors and plays a critical role in cell function and cancer progression. However, little is known about the role of WTAP in ovarian cancer (OC) and its mechanisms. In this study, we found for the first time that hypoxia-inducible factor (HIF)-1α could positively regulate increased expression of WTAP under hypoxia. And further results revealed that WTAP expression was closely associated with the clinicopathological features of OC, and high expression of WTAP predicted low survival rate in patients with OC. In addition, cell proliferation and invasive capacity were significantly reduced after knockdown of WTAP expression in OC cells. However, cell proliferation and invasive ability were significantly enhanced after overexpression of WTAP. Additionally, we find that WTAP interacts with DGCR8 (a crucial chip protein) to regulate the expression of microRNA-200 (miR-200) in an m6A-dependent way. Further experiments showed that the key glycolysis enzyme HK2 could be positively regulated by miR-200, which significantly affected the intracellular Warburg effect. In conclusion, this is considered uncovered that upregulation of WTAP expression by HIF-1α intercedes with miRNA processing, accelerates the Warburg impact, and advances the event and advancement of tumor, thus giving a novel viewpoint on m6A adjustment in OC movement.


Asunto(s)
MicroARNs , Neoplasias Ováricas , Factores de Empalme de ARN , Adenosina/análogos & derivados , Proteínas de Ciclo Celular/genética , Femenino , Humanos , Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , MicroARNs/genética , Neoplasias Ováricas/genética , Factores de Empalme de ARN/genética , Proteínas de Unión al ARN/genética
14.
Med Image Anal ; 77: 102369, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35091279

RESUMEN

Clinical evidence has shown that rib-suppressed chest X-rays (CXRs) can improve the reliability of pulmonary disease diagnosis. However, previous approaches on generating rib-suppressed CXR face challenges in preserving details and eliminating rib residues. We hereby propose a GAN-based disentanglement learning framework called Rib Suppression GAN, or RSGAN, to perform rib suppression by utilizing the anatomical knowledge embedded in unpaired computed tomography (CT) images. In this approach, we employ a residual map to characterize the intensity difference between CXR and the corresponding rib-suppressed result. To predict the residual map in CXR domain, we disentangle the image into structure- and contrast-specific features and transfer the rib structural priors from digitally reconstructed radiographs (DRRs) computed by CT. Furthermore, we employ additional adaptive loss to suppress rib residue and preserve more details. We conduct extensive experiments based on 1673 CT volumes, and four benchmarking CXR datasets, totaling over 120K images, to demonstrate that (i) our proposed RSGAN achieves superior image quality compared to the state-of-the-art rib suppression methods; (ii) combining CXR with our rib-suppressed result leads to better performance in lung disease classification and tuberculosis area detection.


Asunto(s)
Enfermedades Pulmonares , Tórax , Humanos , Radiografía , Reproducibilidad de los Resultados , Costillas/diagnóstico por imagen , Rayos X
15.
Mol Plant ; 15(2): 258-275, 2022 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-34715392

RESUMEN

As one of the most important crops in the world, rice (Oryza sativa) is a model plant for metabolome research. Although many studies have focused on the analysis of specific tissues, the changes in metabolite abundance across the entire life cycle have not yet been determined. In this study, combining both targeted and nontargeted metabolite profiling methods, a total of 825 annotated metabolites were quantified in rice samples from different tissues covering the entire life cycle. The contents of metabolites in different tissues of rice were significantly different, with various metabolites accumulating in the plumule and radicle during seed germination. Combining these data with transcriptome data obtained from the same time period, we constructed the Rice Metabolic Regulation Network. The metabolites and co-expressed genes were further divided into 12 clusters according to their accumulation patterns, with members within each cluster displaying a uniform and clear pattern of abundance across development. Using this dataset, we established a comprehensive metabolic profile of the rice life cycle and used two independent strategies to identify novel transcription factors-namely the use of known regulatory genes as bait to screen for new networks underlying lignin metabolism and the unbiased identification of new glycerophospholipid metabolism regulators on the basis of tissue specificity. This study thus demonstrates how guilt-by-association analysis of metabolome and transcriptome data spanning the entire life cycle in cereal crops provides novel resources and tools to aid in understanding the mechanisms underlying important agronomic traits.


Asunto(s)
Oryza , Animales , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/genética , Estadios del Ciclo de Vida , Metaboloma/genética , Oryza/metabolismo , Transcriptoma/genética
16.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(2): 119-124, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33825367

RESUMEN

Effects of heat treatment conditions (including temperature and time) on the shape memory recovery and corrosion resistance of NiTi self-expanding vascular stents were studied based on working mechanism and clinical use. The Af temperature, dimensional recovery, crush resistance with radially applied load and point applied load of stents and corrosion resistance were characterized in diffident heat treatment conditions. The research results allow the conclusion that the stent treated at 500 ℃ for 10 min has optimum performance, and corrosion resistance meets the requirements.


Asunto(s)
Aleaciones , Calor , Corrosión , Ensayo de Materiales , Stents , Propiedades de Superficie , Temperatura , Titanio
17.
Front Neurol ; 12: 695187, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35082742

RESUMEN

Pain is a multidimensional process, which can be modulated by emotions; however, the mechanisms underlying this modulation are unknown. We used pictures with different emotional valence (negative, positive, and neutral) as primes and applied electrical painful stimuli as targets to healthy participants. We assessed pain intensity and unpleasantness ratings and recorded electroencephalograms (EEGs). We found that pain unpleasantness and not pain intensity ratings were modulated by emotion, with increased ratings for negative and decreased ratings for positive pictures. We also found two consecutive gamma band oscillations (GBOs) related to pain processing from time frequency analyses of the EEG signals. The early GBO had a cortical distribution contralateral to the painful stimulus and its amplitude was positively correlated with intensity and unpleasantness ratings, but not with prime valence. The late GBO had a centroparietal distribution and its amplitude was larger for negative compared to neutral and positive pictures. The emotional modulation effect (negative vs. positive) of the late GBO amplitude was positively correlated with pain unpleasantness. The early GBO might reflect the overall pain perception, possibly involving the thalamocortical circuit, while the late GBO might be related to the affective dimension of pain and top-down-related processes.

18.
Eur J Pain ; 24(7): 1314-1329, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32335979

RESUMEN

BACKGROUND: Following amputation, nearly all amputees report nonpainful phantom phenomena and many of them suffer from chronic phantom limb pain (PLP) and residual limb pain (RLP). The aetiology of PLP remains elusive and there is an ongoing debate on the role of peripheral and central mechanisms. Few studies have examined the entire somatosensory pathway from the truncated nerves to the cortex in amputees with PLP compared to those without PLP. The relationship among afferent input, somatosensory responses and the change in PLP remains unclear. METHODS: Transcutaneous electrical nerve stimulation was applied on the truncated median nerve, the skin of the residual limb and the contralateral homologous nerve in 22 traumatic upper-limb amputees (12 with and 10 without PLP). Using somatosensory event-related potentials, the ascending volley was monitored from the brachial plexus, the spinal cord, the brainstem and the thalamus to the primary somatosensory cortex. RESULTS: Peripheral input could evoke PLP in amputees with chronic PLP (7/12), but not in amputees without a history of PLP (0/10). The amplitudes of the somatosensory components were comparable between amputees with and without PLP. In addition, evoked potentials from the periphery through the spinal, subcortical and cortical segments were not significantly associated with PLP. CONCLUSIONS: Peripheral input can modulate PLP but seems insufficient to cause PLP. These findings suggest the multifactorial complexity of PLP and different mechanisms for PLP and RLP. SIGNIFICANCE: Peripheral afferent input plays a role in PLP and has been assumed to be sufficient to generate PLP. In this study we found no significant differences in the electrical potentials generated by peripheral stimulation from the truncated nerve and the skin of the residual limb in amputees with and without PLP. Peripheral input could enhance existing PLP but could not cause it. These findings indicate the multifactorial complexity of PLP and an important role of central processes in PLP.


Asunto(s)
Amputados , Miembro Fantasma , Potenciales Evocados , Humanos , Corteza Somatosensorial , Extremidad Superior
19.
Biomed Rep ; 12(4): 171-177, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32190305

RESUMEN

Circular RNAs (circRNAs) are novel non-coding RNAs that have been reported to be involved in the progression of numerous diseases. However, the clinical diagnostic value of circRNAs in female reproductive system diseases remains unknown. The present study is a systemic review and meta-analysis of the available literature on circRNAs as novel biomarkers for female reproductive system diseases. Relevant studies were systematically searched using the PubMed, Embase, Web of Science and Cochrane Library databases. The data obtained from the included studies were analyzed by RevMan5.3 and STATA 14.2. A total of six studies involving 613 individuals across three types of disease examined the diagnostic capabilities of circRNAs. Within these publications, the pooled sensitivity of circRNAs was 0.70 (95% CI, 0.64-0.76), and the pooled specificity was 0.70 (95% CI, 0.64-0.75). The pooled positive likelihood ratio and negative likelihood ratio were 2.33 and 0.42, respectively. The diagnostic score was 1.70 and the pooled diagnostic odds ratio was 5.48. The area under the summary receiver operator characteristic curve was 0.76 (95% CI, 0.72-0.79), indicating that circRNAs exhibited a moderate diagnostic value for female reproductive system diseases and may function as potential diagnostic biomarkers. However, further studies are required to verify the clinical applications of circRNAs.

20.
Neuroscience ; 432: 205-215, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32135235

RESUMEN

Rotational uncertainty refers to the fact that the reaction time (RT) for identifying an upright stimulus is longer when the target stimulus is presented in a sequence of stimuli with different orientations (SU condition) than upright stimuli only (AU condition). Up until now, the rotational uncertainty effect has been only revealed by behavior measures, and its underlying neural mechanism remains unclear. In this study, using the hand mental rotation paradigm and electroencephalogram (EEG) recordings, we aimed to find the electrophysiological evidences of the rotational uncertainty from event-related potential (ERP) and event-related (de)synchronization (ERS/ERD) measurements. Compared with the upright hand stimuli in AU condition, the same stimuli in SU condition took longer RT, elicited stronger α-ERD and ß-ERD, and evoked larger P100, P300 and the slow wave (SW) from -500 ms to -200 ms before response. In particular, the amplitude of SW difference (i.e., SWSU - SWAU) was negatively correlated with the extent of rotational uncertainty effect (i.e., RTSU - RTAU), with its source mainly in the right precentral and postcentral gyri, precuneus, and the left inferior parietal lobule. Our results suggested that identifying the upright hand stimuli in SU condition induced more activation of motor networks, and the rotational uncertainty influenced multiple cognitive processes from the early visual processing to the late mental rotation and judging phases. The results implied that in SU condition, subjects might maintain readiness for the next possible mental rotation immediately after the previous response, with more attention to the coming visual stimuli. Even for the upright stimuli, they might still prepare for the mental rotation, and even mentally rotate the stimuli in a minor angle.


Asunto(s)
Electroencefalografía , Potenciales Evocados , Cognición , Humanos , Tiempo de Reacción , Incertidumbre
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