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1.
Langmuir ; 40(1): 1072-1078, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38154099

RESUMEN

The delicate regulation of structural phase transition can provide advanced approaches for fabricating desired and well-organized nanoarchitectures on surfaces. Introduction of metal ions into pure organic systems can facilitate the phase transition from hydrogen-bonded structures to metal-organic structures by coordinating with organic molecules. However, it remains a challenge to attain a phase transition dominated by variable metal coordination configurations through adjustment of the metal ion concentration. Herein, we report the phase transitions of naphthalene-2,3-carbonitride (2,3-DCN) molecules on highly oriented pyrolytic graphite (HOPG) under varying solvents and Cu2+ ion concentrations. By integrating data from scanning tunneling microscopy imaging and density functional theory calculations, it is demonstrated that phase transitions of 2,3-DCN occur through forming diverse coordination configurations where Cu2+ ions can coordinate with 2,3-DCN and 1-nonanoic acid or Cl- ions to form different ligand components with a coordination number of 4 when varying the molar ratios of 2,3-DCN to Cu2+ ion in the 1-nonanoic acid solvent. However, in the case of 1-heptanoic acid as a solvent, the self-assembly structure of 2,3-DCN only changes via the alteration of hydrogen bonding sites and Cu2+ ions do not coordinate with 2,3-DCN molecules. These findings provide valuable insights into the coordination behavior of metal ions in different solvents.

2.
Sensors (Basel) ; 24(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38931610

RESUMEN

Large-scale multi-building and multi-floor indoor localization has recently been the focus of intense research in indoor localization based on Wi-Fi fingerprinting. Although significant progress has been made in developing indoor localization algorithms, few studies are dedicated to the critical issues of using existing and constructing new Wi-Fi fingerprint databases, especially for large-scale multi-building and multi-floor indoor localization. In this paper, we first identify the challenges in using and constructing Wi-Fi fingerprint databases for large-scale multi-building and multi-floor indoor localization and then provide our recommendations for those challenges based on a case study of the UJIIndoorLoc database, which is the most popular publicly available Wi-Fi fingerprint multi-building and multi-floor database. Through the case study, we investigate its statistical characteristics with a focus on the three aspects of (1) the properties of detected wireless access points, (2) the number, distribution and quality of labels, and (3) the composition of the database records. We then identify potential issues and ways to address them using the UJIIndoorLoc database. Based on the results from the case study, we not only provide valuable insights on the use of existing databases but also give important directions for the design and construction of new databases for large-scale multi-building and multi-floor indoor localization in the future.

3.
Sensors (Basel) ; 24(3)2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38339745

RESUMEN

Location fingerprinting using Received Signal Strength Indicators (RSSIs) has become a popular technique for indoor localization due to its use of existing Wi-Fi infrastructure and Wi-Fi-enabled devices. Artificial intelligence/machine learning techniques such as Deep Neural Networks (DNNs) have been adopted to make location fingerprinting more accurate and reliable for large-scale indoor localization applications. However, the success of DNNs for indoor localization depends on the availability of a large amount of pre-processed and labeled data for training, the collection of which could be time-consuming in large-scale indoor environments and even challenging during a pandemic situation like COVID-19. To address these issues in data collection, we investigate multi-dimensional RSSI data augmentation based on the Multi-Output Gaussian Process (MOGP), which, unlike the Single-Output Gaussian Process (SOGP), can exploit the correlation among the RSSIs from multiple access points in a single floor, neighboring floors, or a single building by collectively processing them. The feasibility of MOGP-based multi-dimensional RSSI data augmentation is demonstrated through experiments using the hierarchical indoor localization model based on a Recurrent Neural Network (RNN)-i.e., one of the state-of-the-art multi-building and multi-floor localization models-and the publicly available UJIIndoorLoc multi-building and multi-floor indoor localization database. The RNN model trained with the UJIIndoorLoc database augmented with the augmentation mode of "by a single building", where an MOGP model is fitted based on the entire RSSI data of a building, outperforms the other two augmentation modes and results in the three-dimensional localization error of 8.42 m.

4.
Prev Med ; 173: 107612, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37442211

RESUMEN

In today's era, the rapid spread of information and the rise of major network platforms provide good conditions for online learning and at the same time provide a new development idea for basketball teaching. The establishment of modern multimedia teaching theory provides theoretical support for the research and development of this subject. Construct and apply the online learning system of basketball basic technology, provide high-quality education, and can accommodate a large number of basketball fans to study and exchange together, and improve the physical fitness of young people. This thesis combines the multi-target localization algorithm in wireless sensor networks, first introduces the related concepts and basic theories of UWSNs, and then summarizes the related theories of node localization technology. In the course of basketball teaching, the advantages and disadvantages of the wireless sensor network multi-target positioning algorithm and the research direction are introduced. Aiming at the problem of low positioning accuracy and high complexity of the basketball motion prediction positioning algorithm, a multi-target positioning algorithm improved by backtracking search is proposed. The MBSA algorithm improves the positioning accuracy of anchor points, and uses cooperation mechanisms and basketball mobility to locate nodes for unknown actions. An improved BSA algorithm, namely the KLBSA-LoT algorithm, is proposed. The KLBSA-LoT algorithm accurately locates the anchor point and uses a cooperative mechanism to predict the position information of unknown nodes in basketball. Applying this algorithm to basketball teaching can greatly improve the accuracy of its positioning training. Sports teaching provides new methods.


Asunto(s)
Baloncesto , Humanos , Adolescente , Escolaridad , Algoritmos , Aptitud Física , Tecnología
5.
J Nanobiotechnology ; 21(1): 177, 2023 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-37268942

RESUMEN

Long-term chronic inflammation after Achilles tendon injury is critical for tendinopathy. Platelet-rich plasma (PRP) injection, which is a common method for treating tendinopathy, has positive effects on tendon repair. In addition, tendon-derived stem cells (TDSCs), which are stem cells located in tendons, play a major role in maintaining tissue homeostasis and postinjury repair. In this study, injectable gelatine methacryloyl (GelMA) microparticles containing PRP laden with TDSCs (PRP-TDSC-GM) were prepared by a projection-based 3D bioprinting technique. Our results showed that PRP-TDSC-GM could promote tendon differentiation in TDSCs and reduce the inflammatory response by downregulating the PI3K-AKT pathway, thus promoting the structural and functional repair of tendons in vivo.


Asunto(s)
Plasma Rico en Plaquetas , Tendinopatía , Ratas , Animales , Hidrogeles/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Tendones , Tendinopatía/terapia , Tendinopatía/metabolismo , Células Madre , Plasma Rico en Plaquetas/metabolismo , Impresión Tridimensional
6.
Ecotoxicol Environ Saf ; 262: 115204, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37393816

RESUMEN

Arsenic exposure increases the risk of bladder cancer in humans, but its underlying mechanisms remain elusive. The alanine, serine, cysteine-preferring transporter 2 (ASCT2, SLC1A5) is frequently overexpressed in cancer cells. The aim of this study was to evaluate the effects of arsenic on SLC1A5, and to determine the role of SLC1A5 in the proliferation and self-renewal of uroepithelial cells. F344 rats were exposed to 87 mg/L NaAsO2 or 200 mg/L DMAV for 12 weeks. The SV-40 immortalized human uroepithelial (SV-HUC-1) cells were cultured in medium containing 0.5 µM NaAsO2 for 40 weeks. Arsenic increased the expression levels of SLC1A5 and ß-catenin both in vivo and in vitro. SLC1A5 promoted cell proliferation and self-renewal by activating ß-catenin, which in turn was dependent on maintaining GSH/ROS homeostasis. Our results suggest that SLC1A5 is a potential therapeutic target for arsenic-induced proliferation and self-renewal of uroepithelial cells.

7.
Phys Chem Chem Phys ; 24(5): 3030-3034, 2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35039814

RESUMEN

Using a template to control the on-surface polymerization process is valuable for building functional molecular nanostructures. Here, the role of the symmetric matching between a halogen-ligand component (H2TBrPP) and the substrate for the fabrication of a regular metal-organic structure on Cu(111) and Cu(100) surfaces was studied using scanning tunnelling microscopy (STM). Considering the formation of short-range order polymers on the Au(111) surface via the process of debromination due to the weak directing effect from the substrate to the precursors, a bilayer of ordered assembled structure of H2TBrPP/Au(111) has been fabricated and the molecules in the top layer are guided by the first-layer molecules. Owing to the steering effect of the substrate-directed molecular template, the H2TBrPP components in the top layer were polymerized into ordered molecular chain arrays along the given direction that is determined by the initial close-packed assembled structure of H2TBrPP components during the post-annealing treatment.

8.
Ecotoxicol Environ Saf ; 244: 114034, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36063615

RESUMEN

2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47) is one of the most important polybrominated diphenyl ethers (PBDEs) congeners, and epidemiological studies have shown that it can cause adverse pregnancy outcomes. The aim of our study was to investigate the role of placental injury in BDE-47-induced adverse pregnancy outcomes through in vivo and in vitro models. From day 0.5 to day 16.5 of pregnancy of ICR mice, BDE-47 oral doses of 0, 25, 50 and 100 mg/kg/day were administered. Immunohistochemical staining found that BDE-47 inhibited the expression of CD34 in mouse placenta, and ELISA results showed that BDE-47 reduced the levels of VEGF and PlGF in the serum of pregnant mice. Western blot assays found that the expression levels of VEGF-A and invasion-related factors were decreased in the placentas of BDE-47-treated group, which indicated that BDE-47 could impair placental angiogenesis. Furthermore, BDE-47 inhibited proliferation, increased apoptosis and autophagy, and activated p38 MAPK signaling pathway in mouse placental tissue. In vitro, HTR-8/SVneo cells were treated with 0, 5, 10, 20 µM BDE-47 for 24 h. Wound healing assays and Transwell assays showed that BDE-47 inhibited the migration and invasion ability of HTR-8/SVneo cells. We also found that BDE-47 inhibited the proliferation of HTR-8/SVneo cells and increased apoptosis and autophagy. BDE-47 activated p38 MAPK signaling pathway in HTR-8/SVneo cells, and inhibition of p38 MAPK signaling pathway in HTR-8/SVneo cells restored the effects caused by BDE-47. In conclusion, BDE-47 impairs placental angiogenesis by inhibiting cell migration and invasion, and induces placental toxicity by inhibiting proliferation, increasing apoptosis and autophagy. In vitro, activation of p38 MAPK signaling pathway is involved in the processes of placental injury by BDE-47.


Asunto(s)
Éteres Difenilos Halogenados , Placenta , Animales , Éter/metabolismo , Éter/farmacología , Femenino , Ratones , Ratones Endogámicos ICR , Placenta/metabolismo , Embarazo , Transducción de Señal , Trofoblastos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
9.
Sensors (Basel) ; 22(14)2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35890961

RESUMEN

In a wireless sensor network (WSN), reducing the energy consumption of battery-powered sensor nodes is key to extending their operating duration before battery replacement is required. Message bundling can save on the energy consumption of sensor nodes by reducing the number of message transmissions. However, bundling a large number of messages could increase not only the end-to-end delays and message transmission intervals, but also the packet error rate (PER). End-to-end delays are critical in delay-sensitive applications, such as factory monitoring and disaster prevention. Message transmission intervals affect time synchronization accuracy when bundling includes synchronization messages, while an increased PER results in more message retransmissions and, thereby, consumes more energy. To address these issues, this paper proposes an optimal message bundling scheme based on an objective function for the total energy consumption of a WSN, which also takes into account the effects of packet retransmissions and, thereby, strikes the optimal balance between the number of bundled messages and the number of retransmissions given a link quality. The proposed optimal bundling is formulated as an integer nonlinear programming problem and solved using a self-adaptive global-best harmony search (SGHS) algorithm. The experimental results, based on the Cooja emulator of Contiki-NG, demonstrate that the proposed optimal bundling scheme saves up to 51.8% and 8.8% of the total energy consumption with respect to the baseline of no bundling and the state-of-the-art integer linear programming model, respectively.


Asunto(s)
Redes de Comunicación de Computadores , Tecnología Inalámbrica , Algoritmos , Suministros de Energía Eléctrica , Fenómenos Físicos
10.
Rheumatology (Oxford) ; 60(5): 2383-2390, 2021 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-33167034

RESUMEN

OBJECTIVES: OA is the most common form of arthritis worldwide and has a major impact on the quality of life among the older population. This study aimed at determining the potential causal effects of several serum nutritional factors on OA. METHODS: A total of seven serum nutritional factors were identified from genome-wide association studies. Summary statistics for OA were obtained from UK Biobank (194 153 for women and 166 988 for men) and a large genome-wide association studies meta-analysis based on the European population (455 221, 393 873 and 403 124 for overall, hip and knee OA, respectively). Two-sample Mendelian randomization approach was used to estimate the causal association between the selected nutritional factors and the risk of OA. RESULTS: The Mendelian randomization analyses suggested that serum calcium levels were inversely associated with overall OA (95% CI, 0.595, 0.850), hip OA (95% CI, 0.352, 0.799) and knee OA (95% CI, 0.461, 0.901). Serum retinol levels were also inversely associated with hip OA (95% CI, 0.257, 0.778). Moreover, sex-specific associations were observed between serum calcium levels (95% CI, 0.936, 0.998), iron levels (95% CI, 1.000, 1.012), selenium levels (95% CI, 0.923, 0.999) and OA in women. CONCLUSION: In this study, an inverse causal association between serum calcium levels and OA was established. Serum retinol levels were inversely associated with hip OA. In addition, we provide evidence for the causal effect of serum calcium, iron and selenium on the risk of OA in women.


Asunto(s)
Calcio/sangre , Hierro/sangre , Osteoartritis/sangre , Selenio/sangre , Vitamina A/sangre , Femenino , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Análisis de la Aleatorización Mendeliana , Estado Nutricional , Factores Sexuales
11.
Langmuir ; 37(12): 3761-3765, 2021 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-33724026

RESUMEN

A series of nucleobases guanine (G) and cytosine (C) pairing configurations have been fabricated on highly oriented pyrolytic graphite (HOPG) surface by controlling the molar ratio of G and C in water solution. Watson-Crick (WC) base pairing governs the association of C and G nucleobases when the molar ratio of C/G is adjusted to 1:1. Nucleobase-rich is preferentially hydrogen-bonded to the sites exposed around WC motifs with the adjustment of the C/G molar ratio. At a higher C/G molar ratio imbalance, the pairing configurations depend on the combination of interspace and sites of hydrogen binding between G and C bases. The systematic analysis of the high-resolution STM images and DFT calculations reveal that hydrogen bonding plays a dominant role in the formation of these pairing configurations and that the competition between the priority and diversity of hydrogen-bonded configurations bonding between G and C is the key for the pairing structural polymorphism.


Asunto(s)
Citosina , Grafito , Emparejamiento Base , Guanina , Enlace de Hidrógeno , Agua
12.
Ecotoxicol Environ Saf ; 208: 111693, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396024

RESUMEN

Arsenic is a natural chemical element that is strongly associated with bladder cancer. Understanding the underlying mechanisms behind the association between arsenic and bladder cancer as well as identifying effective preventive interventions will help reduce the incidence and mortality of this disease. The epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) properties play key roles in cancer development and progression. Here, we reported that chronic exposure to arsenic resulted in EMT and increased levels of the CSC marker CD44 in human uroepithelial cells. Furthermore, IL-8 promoted a mesenchymal phenotype and upregulated CD44 by activating the ERK, AKT and STAT3 signaling. Phosphorylation of the human epidermal growth factor receptor 2 (HER2) was key for arsenic-induced IL-8 overexpression and depended on the simultaneous activation of the MAPK, JNK, PI3K/AKT and GSK3ß signaling pathways. We also found that genistein inhibited arsenic-induced HER2 phosphorylation and downregulated its downstream signaling pathways, thereby inhibiting progression of EMT, and reducing CD44 expression levels. These results demonstrate that the HER2/IL-8 axis is related to the acquisition of an EMT phenotype and CSCs in arsenic-treated cells. The inhibitory effects of genistein on EMT and CSCs provide a new perspective for the intervention and potential chemotherapy against arsenic-induced bladder cancer.


Asunto(s)
Arsénico/toxicidad , Células Epiteliales/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Interleucina-8/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Receptor ErbB-2/genética , Vejiga Urinaria/metabolismo , Arsénico/metabolismo , Línea Celular , Movimiento Celular/efectos de los fármacos , Movimiento Celular/inmunología , Supervivencia Celular/efectos de los fármacos , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Transición Epitelial-Mesenquimal/inmunología , Humanos , Receptores de Hialuranos/genética , Células Madre Neoplásicas/inmunología , Células Madre Neoplásicas/metabolismo , Fenotipo , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/efectos de los fármacos , Vejiga Urinaria/citología
13.
FASEB J ; 33(2): 2574-2586, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30285579

RESUMEN

Postmenopausal osteoporosis is initiated by estrogen withdrawal and is characterized mainly by overactivated osteoclastic bone resorption. Targeting TNF receptor-associated factor 6 (TRAF6) or its downstream signaling pathways to modulate osteoclast formation and function is an appealing strategy for osteoclast-related disorders. In the present study, we determined the effect of tomatidine, a steroidal alkaloid derived from Solanaceae, on the formation and function of receptor activator of NF-κB (RANK) ligand-induced osteoclasts and the underlying mechanism. Tomatidine inhibited osteoclast formation in a dose-dependent manner and decreased the expression of osteoclast marker genes. Actin ring formation and osteoclastic bone resorption were attenuated in the presence of tomatidine in vitro. Eight weeks after ovariectomy, tomatidine prevented estrogen deficiency-induced bone loss and restored the mechanical properties of the femur. At the molecular level, tomatidine abrogated phosphorylation of c-Jun N-terminal kinase (JNK)/p38, NF-κB, and protein kinase B (Akt) pathway proteins by suppressing RANK expression, inhibiting the binding of TRAF6 to RANK, and downregulating the osteoclastogenesis marker-related protein expression. In summary, these data demonstrated that tomatidine attenuated osteoclast formation and function by modulating multiple TRAF6-mediated pathways. Therefore, tomatidine could be a novel candidate for the treatment of osteoclast-related disorders, including osteoporosis.-Hu, B., Sun, X., Yang, Y., Ying, Z., Meng, J., Zhou, C., Jiang, G., Li, S., Wu, F., Zhao, X., Zhu, H., Wu, H., Cai, X., Shi, Z., Yan, S. Tomatidine suppresses osteoclastogenesis and mitigates estrogen deficiency-induced bone mass loss by modulating TRAF6-mediated signaling.


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Estrógenos/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Factor 6 Asociado a Receptor de TNF/metabolismo , Tomatina/análogos & derivados , Animales , Resorción Ósea/etiología , Resorción Ósea/metabolismo , Resorción Ósea/patología , Diferenciación Celular , Células Cultivadas , Femenino , Humanos , Ratones Endogámicos C57BL , FN-kappa B/genética , FN-kappa B/metabolismo , Osteoclastos/citología , Osteoclastos/metabolismo , Ovariectomía/efectos adversos , Transducción de Señal , Factor 6 Asociado a Receptor de TNF/genética , Tomatina/farmacología
14.
Med Sci Monit ; 26: e920711, 2020 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-32148334

RESUMEN

BACKGROUND The suicide risk of patients with cancer is higher than the general population. Our research aimed to explore the Surveillance, Epidemiology, and End Results (SEER) database to define incidence and quest risk factors for death of suicide in patients with Kaposi's sarcoma (KS) in the United States (US). MATERIAL AND METHODS We screened KS patients without human immunodeficiency virus status in the SEER database from 1980 to 2016, calculated the standardized mortality ratios of them by comparing the rates with those of the US general population from 1980 to 2016, and identified relevant suicide risk factors by univariable and multivariable logistic regression analyses. RESULTS The suicide rates of KS patients and US general population were 115.31 (110 suicides among 21 405 patients) and 15.1 per 100 000 person-years, respectively, thus the standardized mortality ratio was 7.64 (95% confidence interval [CI], 6.28-9.21). The multivariate analysis showed that black race (versus white race, hazard ratio [HR]: 0.43, 95% CI: 0.21-0.89, P=0.022), advanced age at diagnosis (≥55 years versus 18-44 years, HR: 0.31, 95% CI: 0.14-0.66, P=0.002), and chemotherapy (versus no chemotherapy, HR: 0.60, 95% CI: 0.37-0.96, P=0.032) were protective factors for suicide among KS patients. CONCLUSIONS Clinicians and caregivers can apply our findings to identify KS patients with high suicide risk characteristics (white race, age of 18-44 years, non-chemotherapy) and exert timely interventions during patient diagnosis, treatment, and follow-up to reduce the suicide rate in this population.


Asunto(s)
Sarcoma de Kaposi/psicología , Suicidio , Adolescente , Adulto , Factores de Edad , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Programa de VERF , Sarcoma de Kaposi/tratamiento farmacológico , Estados Unidos , Población Blanca , Adulto Joven
15.
J Cell Mol Med ; 23(10): 6730-6743, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31328430

RESUMEN

Osteoclast overactivation-induced imbalance in bone remodelling leads to pathological bone destruction, which is a characteristic of many osteolytic diseases such as rheumatoid arthritis, osteoporosis, periprosthetic osteolysis and periodontitis. Natural compounds that suppress osteoclast formation and function have therapeutic potential for treating these diseases. Stachydrine (STA) is a bioactive alkaloid isolated from Leonurus heterophyllus Sweet and possesses antioxidant, anti-inflammatory, anticancer and cardioprotective properties. However, its effects on osteoclast formation and function have been rarely described. In the present study, we found that STA suppressed receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced osteoclast formation and bone resorption, and reduced osteoclast-related gene expression in vitro. Mechanistically, STA inhibited RANKL-induced activation of NF-κB and Akt signalling, thus suppressing nuclear factor of activated T cells c1 induction and nuclear translocation. In addition, STA alleviated bone loss and reduced osteoclast number in a murine model of LPS-induced inflammatory bone loss. STA also inhibited the activities of NF-κB and NFATc1 in vivo. Together, these results suggest that STA effectively inhibits osteoclastogenesis both in vitro and in vivo and therefore is a potential option for treating osteoclast-related diseases.


Asunto(s)
FN-kappa B/metabolismo , Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteólisis/tratamiento farmacológico , Prolina/análogos & derivados , Proteínas Proto-Oncogénicas c-akt/metabolismo , Actinas/metabolismo , Transporte Activo de Núcleo Celular/efectos de los fármacos , Transporte Activo de Núcleo Celular/genética , Animales , Núcleo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Lipopolisacáridos/toxicidad , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Factores de Transcripción NFATC/metabolismo , Osteoclastos/metabolismo , Osteogénesis/genética , Osteólisis/inducido químicamente , Osteólisis/diagnóstico por imagen , Osteólisis/metabolismo , Prolina/farmacología , Prolina/uso terapéutico , Ligando RANK/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Linfocitos T/metabolismo , Tomografía Computarizada por Rayos X
17.
Front Neurol ; 15: 1360511, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38715691

RESUMEN

Background: Cerebral vasospasm (CV) is a common complication of aneurysmal subarachnoid hemorrhage (aSAH), leading to increased morbidity and mortality rates. Endovascular therapy, particularly intra-arterial vasodilator infusion (IAVI), has emerged as a potential alternative treatment for CV. Methods: A systematic review and meta-analysis were conducted to compare the efficacy of endovascular therapy with standard treatment in patients with CV following aSAH. The primary outcomes assessed were in-hospital mortality, discharge favorable outcome, and follow-up favorable outcome. Secondary outcomes included major infarction on CT, ICU stay duration, and total hospital stay. Results: Regarding our primary outcomes of interest, patients undergoing intervention exhibited a significantly lower in-hospital mortality compared to the standard treatment group, with the intervention group having only half the mortality risk (RR = 0.49, 95% CI [0.29, 0.83], p = 0.008). However, there were no significant differences between the two groups in terms of discharge favorable outcome (RR = 0.99, 95% CI [0.68, 1.45], p = 0.963) and follow-up favorable outcome (RR = 1.09, 95% CI [0.86, 1.39], p = 0.485). Additionally, there was no significant difference in major infarction rates (RR = 0.79, 95% CI [0.34, 1.84], p = 0.588). It is important to note that patients undergoing endovascular treatment experienced longer stays in the ICU (MD = 6.07, 95% CI [1.03, 11.12], p = 0.018) and extended hospitalization (MD = 5.6, 95% CI [3.63, 7.56], p < 0.001). Subgroup analyses based on the mode of endovascular treatment further supported the benefits of IAVI in lowering in-hospital mortality (RR = 0.5, 95% CI [0.27, 0.91], p = 0.023). Conclusion: Endovascular therapy, particularly IAVI, holds promising potential in reducing in-hospital mortality for patients with CV following aSAH. However, it did not show significant improvement in long-term prognosis and functional recovery. Further research with larger sample sizes and randomized controlled trials is necessary to validate these findings and optimize the treatment strategy for cerebral vasospasm in aSAH patients. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42023451741.

18.
Materials (Basel) ; 17(1)2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38203858

RESUMEN

FRP tendons and cables are increasingly being used in civil engineering structures due to their high strength-to-weight ratio and corrosion resistance. The bond anchorage factors, which characterize the bond strength between the FRP tendon/cable and the surrounding materials, play a critical role in determining the overall performance of the system. In this study, a series of tensile tests were conducted on FRP tendons/cables with different bond anchorage factors to evaluate their load-carrying capacity, load-displacement curve, and strain distribution. The study considered different types and surface shapes of FRP tendons/cables, and determined the influence of anchoring length, bonding medium type, and bonding medium thickness on the performance. The strain distribution of FRP tendons/cables at the anchorage end gradually increased along the loading section to the free end. A stress analysis model of the anchoring section was proposed and found to be consistent with the test results.

19.
Front Neurol ; 14: 1224425, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37670774

RESUMEN

Background: Carotid cavernous fistula (CCF) refers to the abnormal arteriovenous communication between the carotid system at the skull base and the sphenoid cavernous sinus, which is caused by trauma in almost 75% of cases. The drainage of venous blood to the spinal cord represents a distinctive mechanism, which is commonly observed in dural arteriovenous fistula (DAVF), and typically manifests clinically as progressive myelopathy. However, it is a rare occurrence in clinical practice that traumatic carotid cavernous fistula (TCCF) causes delayed quadriplegia through perimedullary venous drainage. Case presentation: We report the case of a 29-year-old male patient who was admitted to the hospital with a sudden onset of headache and quadriplegia. The patient had previously lost his right eye in a traffic accident 5 years ago. Cerebral angiography showed a high-flow direct CCF on the right side, accompanied by obvious drainage of cerebellar and perimedullary veins. We successfully performed coil embolization for the CCF, and the symptoms of the patient gradually improved after the operation. During follow-up at sixth-months, the patient regained the ability to walk independently. Conclusion: We experienced a rare case of TCCF with quadriplegia. Utilizing coil embolization, we achieved successful improvement in the patient's condition. However, the mechanism and the best treatment of CCF drainage through the perimedullary vein are still unclear. We need to further explore the pathophysiological information of CCF venous drainage.

20.
Acta Biomater ; 161: 80-99, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36804538

RESUMEN

The regenerative capabilities including self-renewal, migration and differentiation potentials shift from the embryonic phase to the mature period of endogenous tendon stem/progenitor cells (TSPCs) characterize restricted functions and disabilities following tendon injuries. Recent studies have shown that tendon regeneration and repair rely on multiple specific transcription factors to maintain TSPCs characteristics and functions. Here, we demonstrate Yap, a Hippo pathway downstream effector, is associated with TSPCs phenotype and regenerative potentials through gene expression analysis of tendon development and repair process. Exosomes have been proven an efficient transport platform for drug delivery. In this study, purified exosomes derived from donor platelets are loaded with recombinant Yap1 protein (PLT-Exo-Yap1) via electroporation to promote the stemness and differentiation potentials of TSPCs in vitro. Programmed TSPCs with Yap1 import maintain stemness and functions after long-term passage in vitro. The increased oxidative stress levels of TSPCs are related to the phenotype changes in duplicative senescent processes. The results show that treatment with PLT-Exo-Yap1 significantly protects TSPCs against oxidative stressor-induced stemness loss and senescence-associated secretory phenotype (SASP) through the NF-κB signaling pathway. In addition, we fabricate an Exos-Yap1-functioned GelMA hydrogel with a parallel-aligned substrate structure to enhance TSPCs adhesion, promote cell stemness and force regenerative cells toward the tendon lineage for in vitro and in vivo tendon regeneration. The application of Exos-Yap1 functioned implant assists new tendon-like tissue formation with good mechanical properties and locomotor functions in a full-cut Achilles tendon defect model. Thus, PLT-Exo-Yap1-functionalized GelMA promotes the rejuvenation of TSPCs to facilitate functional tendon regeneration. STATEMENT OF SIGNIFICANCE: This is the first study to explore that the hippo pathway downstream effector Yap is involved in tendon aging and repair processes, and is associated with the regenerative capabilities of TSPCs. In this syudy, Platelet-derived exosomes (PLT-Exos) act as an appropriate carrier platform for the delivery of recombinant Yap1 into TSPCs to regulate Yap activity. Effective Yap1 delivery inhibit oxidative stress-induced senescence associated phenotype of TSPCs by blocking ROS-mediated NF-κb signaling pathway activation. This study emphasizes that combined application of biomimetic scaffolds and Yap1 loaded PLT-Exos can provide structural support and promote rejuvenation of resident cells to assist functional regeneration for Achilles tendon defect, and has the prospect of clinical setting.


Asunto(s)
Tendón Calcáneo , Exosomas , Rejuvenecimiento , FN-kappa B/metabolismo , Plaquetas , Proliferación Celular , Células Madre , Factores de Transcripción/metabolismo , Regeneración
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