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2.
Environ Int ; 185: 108571, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38471262

RESUMO

Isolated effects of single endocrine-disrupting chemicals (EDCs) on male reproductive health have been studied extensively, but their mixture effect remains unelucidated. Previous research has suggested that consuming diet enriched in omega-3 polyunsaturated fatty acids (PUFA) might be beneficial for reproductive health, whether omega-3 PUFA could moderate the effect of EDCs mixture on semen quality remains to be explored. In this study of 155 male recruited from a reproductive health center in China, we used targeted-exposomics to simultaneously measure 55 EDCs in the urine for exposure burden. Regression analyses were restricted to highly detected EDCs (≥55%, n = 34), and those with consistently elevated risk were further screened and brought into mixture effect models (Bisphenol A, ethyl paraben, methyl paraben [MeP], benzophenone-1 [BP1], benzophenone-3, mono(3-carboxypropyl) phthalate [MCPP]). Bayesian Kernel Machine Regression (BKMR) and quantile-based g-computation (QGC) models demonstrated that co-exposure to top-ranked EDCs was related to reduced sperm total (ß = -0.18, 95%CI: -0.29 - -0.07, P = 0.002) and progressive motility (ß = -0.27, 95%CI: -0.43 - -0.10, P = 0.002), but not to lower semen volume. BP1, MeP and MCPP were identified as the main effect driver for deteriorated sperm motion parameters using mixture model analyses. Seminal plasma fatty acid profiling showed that high omega-3 PUFA status, notably elevated docosapentaenoic acid (DPA, C22:5n-3) status, moderated the association between MCPP and sperm motion parameters (total motility: ß = 0.26, 95%CI: 0.01 - -0.51, Pinteraction = 0.047; progressive motility: ß = 0.64, 95%CI: 0.23 - 1.05, Pinteraction = 0.003). Co-exposure to a range of EDCs is mainly associated with deteriorated sperm quality, but to a lesser extent on sperm quantity, high seminal plasma DPA status might be protective against the effect. Our work emphasizes the importance of exposomic approach to assess chemical exposures and highlighted a new possible intervention target for mitigating the potential adverse effect of EDCs on semen quality.


Assuntos
Benzofenonas , Disruptores Endócrinos , Ácidos Graxos Ômega-3 , Ácidos Graxos Insaturados , Masculino , Humanos , Sêmen , Análise do Sêmen , Disruptores Endócrinos/toxicidade , Teorema de Bayes , Espermatozoides
3.
Sci Prog ; 107(1): 368504241227620, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38361488

RESUMO

This article investigates data-driven distributed bipartite formation issues for discrete-time multi-agent systems with communication constraints. We propose a quantized data-driven distributed bipartite formation control approach based on the plant's quantized and saturated information. Moreover, compared with existing results, we consider both the fixed and switching topologies of multi-agent systems with the cooperative-competitive interactions. We establish a time-varying linear data model for each agent by utilizing the dynamic linearization method. Then, using the incomplete input and output data of each agent and its neighbors, we construct the proposed quantized data-driven distributed bipartite formation control scheme without employing any dynamics information of multi-agent systems. We strictly prove the convergence of the proposed algorithm, where the proposed approach can ensure that the bipartite formation tracking errors converge to the origin, even though the communication topology of multi-agent systems is time-varying switching. Finally, simulation and hardware tests demonstrate the effectiveness of the proposed scheme.

4.
Eur Cytokine Netw ; 33(4): 79-89, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37227141

RESUMO

BACKGROUND AND OBJECTIVE: Endothelial cell activation plays a critical role in leukocyte recruitment during inflammation and infection. We previously found that cholinergic stimulation (via vagus nerve stimulation) attenuates vascular endothelial impairment and reduces the inflammatory profile in ovariectomized rats. However, the specific molecular mechanism is unclear. This study was designed to explore the effects and molecular mechanisms of cholinergic agonists (acetylcholine [ACh]) on lipopolysaccharide (LPS)-induced endothelial cell activation in vitro. METHODS: Human umbilical vein endothelial cells (HUVECs) were treated with different concentrations of LPS (10/100/1000 ng/mL) to activate endothelial cells. HUVECs were untreated, treated with ACh (10-5 M) alone, treated with 100 ng/mL LPS alone, or treated with different concentrations of ACh (10-9/10-8/10-7/10-6/10-5 M) before LPS stimulation. HUVECs were also pre-treated with 10-6 M ACh with or without mecamylamine (an nAChR blocker) (10 µΜ) and methyllycaconitine (a specific α7 nAChR blocker) (10 µΜ) and incubated with or without LPS. ELISA, western blotting, cell immunofluorescence, and cell adhesion assays were used to examine inflammatory cytokine production, adhesion molecule expression, monocyte-endothelial cell adhesion and activation of the MAPK/NF-κB pathways. RESULTS: LPS (at 10 ng/mL, 100 ng/mL and 1,000 ng/mL) increased VCAM-1 expression in HUVECs in a dose-dependent manner (with no significant difference between LPS at 100 ng/mL and 1,000 ng/mL). ACh (10-9 M-10-5 M) blocked adhesion molecule expression (VCAM-1, ICAM-1, and E-selectin) and inflammatory cytokine production (TNF-α, IL-6, MCP-1, IL-8) in response to LPS in a dose-dependent manner (with no significant difference between 10-5 and 10-6 M Ach). LPS was also shown to significantly enhance monocyte-endothelial cell adhesion, which was largely abrogated by treatment with ACh (10-6M). VCAM-1 expression was blocked by mecamylamine rather than methyllycaconitine. Lastly, ACh (10-6 M) significantly reduced LPS-induced phosphorylation of NF-κB/p65, IκBα, ERK, JNK and p38 MAPK in HUVECs, which was blocked by mecamylamine. CONCLUSIONS: ACh protects against LPS-induced endothelial cell activation by inhibiting the MAPK and NF-κB pathways, which are mediated by nAChR, rather than α7 nAChR. Our results may provide novel insight into the anti-inflammatory effects and mechanisms of ACh.


Assuntos
Lipopolissacarídeos , NF-kappa B , Animais , Humanos , Ratos , Acetilcolina/farmacologia , Acetilcolina/metabolismo , Células Endoteliais da Veia Umbilical Humana/química , Células Endoteliais da Veia Umbilical Humana/metabolismo , Molécula 1 de Adesão Intercelular/análise , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos/farmacologia , Mecamilamina/metabolismo , Mecamilamina/farmacologia , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Molécula 1 de Adesão de Célula Vascular/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos
5.
Neural Comput Appl ; : 1-11, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34566265

RESUMO

This paper proposed a skill transmission technique for the mobile robot via learning by demonstration. When the material is transported to the designated location, the robot can show the human-like capabilities: autonomous tracking target. In this case, a skill transmission framework is designed, which the Kinect sensor is utilized to distinguish human activity recognition to create a planned path. Moreover, the dynamic movement primitive method is implemented to represent the teaching data, and the Gaussian mixture regression is utilized to encode the learning trajectory. Furthermore, in order to realize the accurate position control of trajectory tracking, a model predictive tracking control is investigated, where the recurrent neural network is used to eliminate the uncertain interaction. Finally, some experimental tasks using the mobile robot (BIT-6NAZA) are carried out to demonstrate the effectiveness of the developed techniques in real-world scenarios.

6.
Int J Med Robot ; 17(1): 1-11, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33113264

RESUMO

PURPOSE: Both safety and accuracy are of vital importance for surgical operation procedures. An efficient way to avoid the singularity of the surgical robot concerning safety issues is to maximize its manipulability in robot-assisted surgery. The goal of this work was to validate a dynamic neural network optimization method for manipulability optimization control of a 7-degree of freedom (DoF) robot in a surgical operation. METHODS: Three different paths, a circle, a sinusoid and a spiral were chosen to simulate typical surgical tasks. The dynamic neural network-based manipulability optimization control was implemented on a 7-DoF robot manipulator. During the surgical operation procedures, the manipulability of the robot manipulator and the accuracy of the surgical operation are recorded for performance validation. RESULTS: By comparison, the dynamic neural network-based manipulability optimization control achieved optimized manipulability but with a loss of the accuracy of trajectory tracking (the global error was 1 mm compare to the 0.5 mm error of non-optimized method). CONCLUSIONS: The method validated in this work achieved optimized manipulability with a loss of error. Future works should be introduced to improve the accuracy of the surgical operation.


Assuntos
Procedimentos Cirúrgicos Robóticos , Humanos , Redes Neurais de Computação
7.
J Hazard Mater ; 401: 123262, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32629345

RESUMO

Constructing heterojunctions would result in the change of valence band position, which is an important factor determining the oxidative ability of photo-induced holes, has received scant attention. In this paper, ß-Bi2O3/Bi2O2CO3 composites with different ratios were obtained via ionic-liquid-assisted solvothermal and in-situ calcination processes. UV-vis DRS, Mott-Schottky test, and Kelvin probe measurement showed the change of band gaps of ß-Bi2O3 and Bi2O2CO3 before and after heterojunction formation. SPV, ESR, photocurrent, and scavenger experiments identified the separation efficiency of photo-generated electrons and holes, as well as the active species generated in the photocatalytic process. The photocatalytic mechanism was investigated by the degradation of Rhodamine B (RhB) upon visible-light and simulated sunlight, respectively. The results demonstrated that ß-Bi2O3/Bi2O2CO3 heterojunctions possessed enhanced separation efficiency and higher degradation ability than the individuals under visible-light irradiation due to effective electron transfer. However, lower performance under simulated sunlight was observed, although their separation efficiency remained high. The decisive reason for this was that the up-shift of valence band of Bi2O2CO3 induced by hybridization and the transition of holes from VB of Bi2O2CO3 to that of ß-Bi2O3 with more negative potential decreased the oxidative ability of holes, which surpassed the positive influence of enhanced separation efficiency.

8.
Sheng Li Xue Bao ; 72(6): 716-723, 2020 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-33349828

RESUMO

The "Four-step Teaching of Encouraging and Sharing" is a learner-centered teaching method that advocates teamwork and gives full play to the role of the teacher in guiding learning. It is an innovative teaching approach to realize students' self-transcendence by stimulating students' internal motivation for independent learning, applying group task-driven learning, and giving teachers' feedback to students' sharing. It consists of four steps: teachers' guiding, students' self-regulated learning, team learning and practice, experience sharing. We have applied this method to the teaching practice of physiology and experimental physiological science with a significant impact on teaching effects. This teaching method has also been implemented to other courses in other majors. To solve the problems of reduced communication and interaction, low learning enthusiasm and motivation in online teaching course during COVID-19 pandemic, we recruited 21 undergraduates from different schools and majors. Using the "Tencent Meeting" platform, the authors tried to apply the whole process of the "Four-step Teaching of Encouraging and Sharing" to the online teaching of physiology. Group tests and questionnaires were used to evaluate teaching effects. The results showed that the implementation of the "Online Four-step Teaching of Encouraging and Sharing (OFST)" was feasible and effective, and to a certain extent alleviated the problems of loneliness and low learning motivation of students during online learning caused by home quarantine, which was particularly helpful for long-distance inter-school and inter-discipline team learning.


Assuntos
COVID-19 , Humanos , Aprendizagem , Motivação , Pandemias , SARS-CoV-2
9.
Endocr Connect ; 8(6): 661-671, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30999280

RESUMO

The role of G protein-coupled estrogen receptor 1 (GPER) signaling, including promotion of Ezrin phosphorylation (which could be activated by estrogen), has not yet been clearly identified in triple-negative breast cancer (TNBC). This study aimed to evaluate the prognostic value of GPER and Ezrin in TNBC patients. Clinicopathologic features including age, menopausal status, tumor size, nuclear grade, lymph node metastasis, AJCC TNM stage, and ER, PR and HER-2 expression were evaluated from 249 TNBC cases. Immunohistochemical staining of GPER and Ezrin was performed on TNBC pathological sections. Kaplan-Meier analyses, as well as logistic regressive and Cox regression model tests were applied to evaluate the prognostic significance between different subgroups. Compared to the GPER-low group, the GPER-high group exhibited higher TNM staging (P = 0.021), more death (P < 0.001), relapse (P < 0.001) and distant events (P < 0.001). Kaplan-Meier analysis showed that GPER-high patients had a decreased OS (P < 0.001), PFS (P < 0.001), LRFS (P < 0.001) and DDFS (P < 0.001) than GPER-low patients. However, these differences in prognosis were not statistically significant in post-menopausal patients (OS, P = 0.8617; PFS, P = 0.1905; LRFS, P = 0.4378; DDFS, P = 0.2538). There was a significant positive correlation between GPER and Ezrin expression level (R = 0.508, P < 0.001) and the effect of Ezrin on survival prognosis corresponded with GPER. Moreover, a multivariable analysis confirmed that GPER and Ezrin level were both significantly associated with poor DDFS (HR: 0.346, 95% CI 0.182-0.658, P = 0.001; HR: 0.320, 95% CI 0.162-0.631, P = 0.001). Thus, overexpression of GPER and Ezrin may contribute to aggressive behavior and indicate unfavorable prognosis in TNBC; this may correspond to an individual's estrogen levels.

10.
J Cancer ; 9(20): 3802-3811, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30405852

RESUMO

Triple-negative breast cancer (TNBC) is the most malignant type of breast cancer with ample vascularisation and high vascular endothelial growth factor (VEGF) expression. The sex steroid hormone oestrogen is involved in several cellular activities associated with TNBC regulation. However, the role of oestrogen in VEGF expression and angiogenesis in TNBC remains unclear. In this study, we found that treatment with 17ß-oestradiol (E2) inhibited VEGF mRNA and protein expression in the TNBC cell lines MDA-MB-468 and MDA-MB-436. To further elaborate on the phenomenon of E2-regulated angiogenesis, we showed that conditioned medium from the TNBC cell line MDA-MB-468 treated with E2 inhibits the tube formation ability of human umbilical vein endothelial cells (HUVECs). Additionally, the G-protein-coupled oestrogen receptor-1 (GPER-1)-specific agonist G-1 has a function similar to that of E2. While G-15, the selective antagonist of GPER-1, notably reversed the inhibitory effects of E2 and G-1 on VEGF expression and tube formation, suggesting that GPER-1 is involved in the E2-induced angiogenesis suppression in TNBC cells. Moreover, E2 inhibited in vivo tumour growth and angiogenesis and reduced the expression levels of VEGF, NF-κB/p65, STAT3, and the endothelial marker CD34 in MDA-MB-468 xenograft tumours. Our findings provide important evidence that E2 can inhibit VEGF expression and angiogenesis in TNBC by activating GPER-1, offering additional insight into tumour angiogenesis and targets for drug intervention in TNBC.

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