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1.
Artículo en Inglés | MEDLINE | ID: mdl-38771682

RESUMEN

Gesture recognition has emerged as a significant research domain in computer vision and human-computer interaction. One of the key challenges in gesture recognition is how to select the most useful channels that can effectively represent gesture movements. In this study, we have developed a channel selection algorithm that determines the number and placement of sensors that are critical to gesture classification. To validate this algorithm, we constructed a Force Myography (FMG)-based signal acquisition system. The algorithm considers each sensor as a distinct channel, with the most effective channel combinations and recognition accuracy determined through assessing the correlation between each channel and the target gesture, as well as the redundant correlation between different channels. The database was created by collecting experimental data from 10 healthy individuals who wore 16 sensors to perform 13 unique hand gestures. The results indicate that the average number of channels across the 10 participants was 3, corresponding to an 75% decrease in the initial channel count, with an average recognition accuracy of 94.46%. This outperforms four widely adopted feature selection algorithms, including Relief-F, mRMR, CFS, and ILFS. Moreover, we have established a universal model for the position of gesture measurement points and verified it with an additional five participants, resulting in an average recognition accuracy of 96.3%. This study provides a sound basis for identifying the optimal and minimum number and location of channels on the forearm and designing specialized arm rings with unique shapes.


Asunto(s)
Algoritmos , Gestos , Reconocimiento de Normas Patrones Automatizadas , Humanos , Masculino , Femenino , Adulto , Reconocimiento de Normas Patrones Automatizadas/métodos , Adulto Joven , Miografía/métodos , Mano/fisiología , Voluntarios Sanos , Reproducibilidad de los Resultados
2.
Sci Total Environ ; 931: 172714, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38679108

RESUMEN

Understanding the responses of soybean rhizosphere and functional microbiomes in intercropping scenarios holds promise for optimizing nitrogen utilization in legume-based intercropping systems. This study investigated three cropping layouts under film mulching: sole soybean (S), soybean-maize intercropping in one row (IS), and soybean-maize intercropping in two rows (IIS), each subjected to two nitrogen levels: 110 kg N ha-1 (N110) and 180 kg N ha-1 (N180). Our findings reveal that cropping patterns alter bacterial and nifh communities, with approximately 5 % of soybean rhizosphere bacterial amplicon sequence variants (ASVs) and 42 % of rhizosphere nifh ASVs exhibiting altered abundances (termed sensitive ASVs). Root traits and soil properties shape these communities, with root traits exerting greater influence. Sensitive ASVs drive microbial co-occurrence networks and deterministic processes, predicting 85 % of yield variance and 78 % of partial factor productivity of nitrogen, respectively. These alterations impact bacterial and nifh diversity, complexity, stability, and deterministic processes in legume-based intercropping systems, enhancing performance in terms of yield, nitrogen utilization efficiency, land equivalent ratio, root nodule count, and nodule dry weight under IIS patterns with N110 compared to other treatments. Our findings underscore the importance of field management practices in shaping rhizosphere-sensitive ASVs, thereby altering microbial functions and ultimately impacting the productivity of legume-based intercropping systems. This mechanistic understanding of soybean rhizosphere microbial responses to intercropping patterns offers insights for sustainable intercropping enhancements through microbial manipulation.


Asunto(s)
Agricultura , Glycine max , Microbiota , Rizosfera , Microbiología del Suelo , Glycine max/microbiología , Glycine max/crecimiento & desarrollo , Agricultura/métodos , Nitrógeno/metabolismo , Producción de Cultivos/métodos , Raíces de Plantas/microbiología , Bacterias/metabolismo
3.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167197, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38653353

RESUMEN

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, and moderate exercise holds promise in ameliorating the ongoing neurodegeneration and cognitive decline. Here, we investigated whether exercise-enriched blood plasm could yield a beneficial therapeutic effect on AD pathologies and cognitive decline in transgenic AD (P301S) mice. In this investigation, a cohort of 2-month-old C57BL/6 mice were granted continuous access to either a running wheel or a fixed wheel for 6 weeks. After that, their plasmas were extracted and subsequently injected intravenously into 4.5-month-old P301S mice biweekly over a 6-week period. A comprehensive methodology was then employed, integrating behavioral tests, pathology assessments, and biochemical analyses to unveil the potential anti-dementia implications of exercise-enriched blood plasma in P301S mice. Upon systemic administration, the findings revealed a noteworthy attenuation of hippocampus-dependent behavioral impairments in P301S mice. Conversely, blood plasma from sedentary counterparts exhibited no discernible impact. These effects were intricately associated with the mitigation of neuroinflammation, the augmentation of hippocampal adult neurogenesis, and a reduction of synaptic impairments following the administration of exercise-enriched blood plasma. These findings advance the proposition that administering exercise-enriched blood plasma may serve as an effective prophylactic measure against AD, opening avenues for further exploration and potential therapeutic interventions.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Modelos Animales de Enfermedad , Hipocampo , Ratones Endogámicos C57BL , Ratones Transgénicos , Condicionamiento Físico Animal , Animales , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/sangre , Hipocampo/metabolismo , Hipocampo/patología , Condicionamiento Físico Animal/métodos , Disfunción Cognitiva/terapia , Disfunción Cognitiva/sangre , Ratones , Plasma/metabolismo , Masculino , Neurogénesis
4.
Mol Nutr Food Res ; 68(7): e2300669, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38491393

RESUMEN

Alzheimer's disease (AD) is the most prevailing form of dementia, with long-term high-fat diet (HFD) consumption being a pivotal contributor to AD pathogenesis. As microglial dysfunction is a crucial factor in the AD onset, it becomes imperative to explore the effects of HFD on microglial function and AD pathogenesis. In the present study, 3xTg-AD model mice at the age of 9-month are subjected to random allocation, with one group receiving a standard diet (ND) and the other an HFD for 3 months. Subsequently, transcriptomic profiling of microglia unveils that HFD alters fatty acid metabolism and mediates T cell infiltration. Within the hippocampus, microglia exhibit aberrant morphology and lipid accretion in response to the HFD, evidenced by conspicuously enlarged microglial cell bodies and accumulation of lipid droplets. These lipid-droplet-accumulating microglia exhibit diminished migratory capacity and compromise plaque consolidation, thereby exacerbating the accumulation of ß-amyloid. Noteworthy, the HFD induces T cell infiltration, thereby aggravating neuroinflammation and Tau phosphorylation. Morris water maze test reveals that HFD-consuming mice display marked impairment in memory performance. In summary, this study demonstrates that prolonged HFD consumption exacerbates amyloid deposition, tau pathology, and cognitive deficits, which is associated with the accumulation of lipid droplets within microglia.


Asunto(s)
Enfermedad de Alzheimer , Dieta Alta en Grasa , Animales , Ratones , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Lípidos , Ratones Transgénicos , Microglía , Proteínas tau/metabolismo
5.
PLoS One ; 19(1): e0296935, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38261591

RESUMEN

BACKGROUND: The triglyceride glucose-body mass index (TyG-BMI) has been considered a surrogate marker for assessing insulin resistance. We aimed to correlate the TyG-BMI, triglyceride glucose combined with body mass index, with femoral neck bone mineral density (FN BMD) in non-diabetic elderly men. METHODS: Using data from the National Health and Nutrition Examination Survey (NHANES) database, totally, 1182 eligible men aged ≥ 50 years without diabetes were included in the current study. Smoothed curves were obtained by a two-piecewise linear regression model and the threshold effects were explored by using a smoothing function. RESULTS: TyG-BMI was positive related with and FN BMD with or without adjustment for confounders. However, no typical dose-dependent positive association between TyG-BMI and FN BMD was observed across the TyG-BMI tertiles, indicating a non-linear association. Further analysis by the weighted two-piecewise linear regression model and recursive algorithm suggested that per SD increase in TyG-BMI increased FN BMD by 0.266 gm/cm2 when TyG-BMI lower than 168.20. However, when TyG-BMI is higher than 168.20, FN BMD only increased 0.046 gm/cm2 for per SD increase of TyG-BMI after fully adjustment (OR = 11.258, 95%CI: 6.034, 16.481). Moreover, subgroup analyses showed that higher TyG-BMI levels were related to elevated FN BMD in all groups, suggesting the consistency of the positive association within these stratas. CONCLUSIONS: This study demonstrated that TyG-BMI is positively associated with FN BMD in a nonlinear fashion among elderly men without diabetes, which may be a reliable marker for the early identification of individuals with lower FN BMD.


Asunto(s)
Diabetes Mellitus , Cuello Femoral , Anciano , Masculino , Humanos , Índice de Masa Corporal , Encuestas Nutricionales , Glucosa , Triglicéridos
6.
Exp Gerontol ; 186: 112359, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38184267

RESUMEN

Aging is a gradual process of natural change that occurs after reaching sexual maturity. It is also a known risk factor for many chronic diseases. Recent research has shown that senolytics can extend the lifespans and health spans of model organisms, and they have also been demonstrated effective in treating age-related diseases. In this study, we conducted a high-throughput screening of 156 drugs that targeted the PI3K/AKT/mTOR pathway to identify potential senolytic medications. Among these drugs, PF-04691502 was selected for further investigation to understand its molecular mechanism of action. Our findings indicate that PF-04691502, a dual inhibitor of PI3K/AKT and mTOR, specifically eliminates senescent cells. It reduces the expression levels of key markers of cellular senescence, such as SA-ß-Gal, senescence-associated secretory phenotypes (SASPs) and p16INK4a. Additionally, PF-04691502 inhibits the phosphorylation of S6K and AKT, leading to the apoptosis of senescent cells. These results suggest that PF-04691502 holds promise as a new senolytic drug. This paper provides important insights into the potential application of PF-04691502 in the study of cell senescence.


Asunto(s)
Proteínas Proto-Oncogénicas c-akt , Piridonas , Pirimidinas , Senoterapéuticos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Senescencia Celular , Serina-Treonina Quinasas TOR/metabolismo
7.
J Biol Chem ; 299(12): 105414, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37918806

RESUMEN

The proteins that coordinate the complex transcriptional networks of aging have not been completely documented. Protein 14-3-3zeta is an adaptor protein that coordinates signaling and transcription factor networks, but its function in aging is not fully understood. Here, we showed that the protein expression of 14-3-3zeta gradually increased during aging. High levels of 14-3-3zeta led to shortened lifespan and imbalance of intestinal immune homeostasis in Drosophila, but the decrease in 14-3-3zeta protein levels by RNAi was able to significantly promote the longevity and intestinal immune homeostasis of fruit flies. Importantly, we demonstrate that adult-onset administration of TIC10, a compound that reduces the aging-related AKT and extracellular signal-regulated kinase (ERK) signaling pathways, rescues the shortened lifespan of 14-3-3zeta-overexpressing flies. This finding suggests that 14-3-3zeta plays a critical role in regulating the aging process. Our study elucidates the role of 14-3-3zeta in natural aging and provides the rationale for subsequent 14-3-3zeta-based antiaging research.


Asunto(s)
Proteínas 14-3-3 , Envejecimiento , Proteínas de Drosophila , Drosophila melanogaster , Intestinos , Animales , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Envejecimiento/genética , Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/inmunología , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Longevidad , Transducción de Señal , Intestinos/inmunología
8.
Polymers (Basel) ; 15(19)2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37835963

RESUMEN

Effectively inhibiting the formation of heterocyclic amines (HAs) and advanced glycation end products (AGEs) is crucial to human health. In the present study, chemical model systems were used to evaluate the inhibitory effects of seven hydrocolloids on HA and AGE formation. The results showed that hydrocolloids effectively inhibited the formation of two major AGEs. However, their inhibitory action against HA formation showed unexpected results, wherein alginic acid, carrageenan and konjac glucomannan promoted the formation of 2-Amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP), harmane, norharmane and 2-amino-3,8-dimethyl-imidazo [4,5-f]-quinoline (MeIQx). Only chitosan and pectin showed significant inhibitory effects on HAs, reducing HA levels by 34.5-56.3% and 30.1-56.6%, respectively. In grilled beef patties, the addition of 1.5% chitosan and pectin significantly decreased AGE and HA content by 53.8-67.0% and 46.9-68.1%, respectively. Moreover, it had a limited impact on quality and sensory properties. Further mechanism studies conducted in model systems revealed that chitosan and pectin decreased the formation of key intermediates of AGEs and HAs. These findings suggest that chitosan and pectin are powerful inhibitors against AGE and HA formation with minimal impact on food quality. Therefore, their application in meat preparation and processing could effectively decrease human dietary exposure to HAs and AGEs.

9.
Int J Biol Macromol ; 253(Pt 2): 126875, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37703968

RESUMEN

Enhancing the fire-retardant and antibacterial properties of viscose fabric through a simple strategy is crucial and urgent. In this study, an aminoazole-based cyclotriphosphazene (HATA) was designed and synthesized through nucleophilic substitution between hexachlorocyclotriphosphazene and 3-amino-1,2,4-triazole. The application of a rapid dipping strategy and the use of 10 wt% HATA aqueous solution significantly increased the limiting oxygen index of the viscose fabric from 19.3 % to 28.4 %. In addition, the HATA-treated fabric exhibited self-extinguishing properties in vertical flame testing. The peak heat release rate of HATA-treated fabric, according to pyrolysis combustion flow calorimetry, significantly decreased by over 83 %. The scanning electron microscope images revealed the original woven fabric structure after burning. The thermogravimetric infrared spectroscopy and X-ray photoelectron spectroscopy results confirmed that the introduction HATA in viscose hindered the release of combustible gas and facilitated the formation of a protective char layer. In addition, 10 % HATA-viscose exhibited remarkable antimicrobial properties, achieving 99.96 % and 99.84 % antibacterial rates against Staphylococcus aureus and Escherichia coli, respectively. Furthermore, HATA-treated viscose fabric exhibited favorable mechanical performance, whiteness, and air permeability. This research provides a simple and effective flame-retardant and antibacterial treatment strategy for viscose fabric.


Asunto(s)
Antibacterianos , Retardadores de Llama , Antibacterianos/farmacología , Calorimetría , Escherichia coli , Calor
10.
J Neurochem ; 166(2): 318-327, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37286480

RESUMEN

BACE1 is essential for the generation of amyloid-ß (Aß) that likely initiates the toxicity in Alzheimer's disease (AD). BACE1 activity is mainly regulated by post-translational modifications, but the relationship between these modifications is not fully characterized. Here, we studied the effects of BACE1 SUMOylation on its phosphorylation and ubiquitination. We demonstrate that SUMOylation of BACE1 inhibits its phosphorylation at S498 and its ubiquitination in vitro. Conversely, BACE1 phosphorylation at S498 suppresses its SUMOylation, which results in promoting BACE1 degradation in vitro. Furthermore, an increase in BACE1 SUMOylation is associated with the progression of AD pathology, while its phosphorylation and ubiquitination are decreased in an AD mouse model. Our findings suggest that BACE1 SUMOylation reciprocally influences its phosphorylation and competes against its ubiquitination, which might provide a new insight into the regulations of BACE1 activity and Aß accumulation.


Asunto(s)
Enfermedad de Alzheimer , Secretasas de la Proteína Precursora del Amiloide , Animales , Ratones , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Ácido Aspártico Endopeptidasas/metabolismo , Fosforilación , Sumoilación , Ubiquitinación , Humanos
11.
Nanomaterials (Basel) ; 13(9)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37177057

RESUMEN

Reversible insulator-metal transition (IMT) and structure phase change in vanadium dioxide (VO2) remain vital and challenging with complex polymorphs. It is always essential to understand the polymorphs that coexist in desired VO2 materials and their IMT behaviors. Different electrical properties and lattice alignments in VO2 (M) and VO2 (B) phases have enabled the creation of versatile functional devices. Here, we present polymorphous VO2 thin films with coexistent VO2 (M) and VO2 (B) phases and phase-dependent IMT behaviors. The presence of VO2 (B) phases may induce lattice distortions in VO2 (M). The plane spacing of (011)M in the VO2 (M) phase becomes widened, and the V-V and V-O vibrations shift when more VO2 (B) phase exists in the VO2 (M) matrix. Significantly, the coexisting VO2 (B) phases promote the IMT temperature of the polymorphous VO2 thin films. We expect that such coexistent polymorphs and IMT variations would help us to understand the microstructures and IMT in the desired VO2 materials and contribute to advanced electronic transistors and optoelectronic devices.

12.
Chemphyschem ; 24(11): e202300059, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36880971

RESUMEN

Oxygen defects are among essential issues and required to be manipulated in correlated electronic oxides with insulator-metal transition (IMT). Besides, surface and interface control are necessary but challenging in field-induced electronic switching towards advanced IMT-triggered transistors and optical modulators. Herein, we demonstrated reversible entropy-driven oxygen defect migrations and reversible IMT suppression in vanadium dioxide (VO2 ) phase-change electronic switching. The initial IMT was suppressed with oxygen defects, which is caused by the entropy change during reversed surface oxygen ionosorption on the VO2 nanostructures. This IMT suppression is reversible and reverts when the adsorbed oxygen extracts electrons from the surface and heals defects again. The reversible IMT suppression observed in the VO2 nanobeam with M2 phase is accompanied by large variations in the IMT temperature. We also achieved irreversible and stable IMT by exploiting an Al2 O3 partition layer prepared by atomic layer deposition (ALD) to disrupt the entropy-driven defect migration. We expected that such reversible modulations would be helpful for understanding the origin of surface-driven IMT in correlated vanadium oxides, and constructing functional phase-change electronic and optical devices.

13.
RSC Adv ; 12(55): 35579-35586, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36540398

RESUMEN

Resistive switching has provided a significant avenue for electronic neural networks and neuromorphic systems. Inspired by the active regulation of neurotransmitter secretion, realizing electronic elements with self-adaptive characteristics is vital for matching Joule heating or sophisticated thermal environments in energy-efficient integrated circuits. Here we present energy-adaptive resistive switching via a controllable insulator-metal transition. Memory-related switching is designed and implemented by manipulating conductance transitions in vanadium dioxide. The switching power decreases dynamically by about 58% during the heating process. Furthermore, the thresholds can be controlled by adjusting the insulator-metal transition processes in such nanowire-based resistive switching, and then preformed in a wide range of operating temperatures. We believe that such power-adaptive switching is of benefit for intelligent memory devices and neuromorphic electronics with low energy consumption.

14.
Front Psychol ; 13: 1037536, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36506991

RESUMEN

As a new organizational form for the coordinated development of education and industry, industrial college is an important carrier for application-oriented colleges and universities to implement application-oriented talent training. Based on Theory of Planned Behavior (TPB) as a theoretical framework, this research constructs a model of the influencing factors of college students' participating in industrial colleges from five criteria: behavioral attitudes, subjective norms, perceived behavioral control, behavioral intentions and situational factors. In this study, participants (N = 541) have completed a questionnaire to assess their behavior of participation in the industrial colleges by using the structural equation model (SEM). It turns out that perceived needs, mandatory norms, exemplary norms, and self-efficacy significantly positively affect college students' intention to participate in industrial colleges. Behavior intention and self-efficacy significantly positively affect college students' participation in industrial colleges. Behavior intentions act as a complete mediator between perceived needs and behavior, as well as between exemplary norms and behavior. Behavioral intentions partially mediate between mandatory norms and behavior, as well as between self-efficacy and behavior. In addition, school support plays a significant positive moderating role in college students' intention and behavior of participating in industrial colleges. These findings not only expand the relevant literature on college students' learning behavior, but also provide useful enlightenment for college education managers on how to stimulate college students' endogenous motivation to participate in industrial colleges.

15.
Front Immunol ; 13: 995645, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36389678

RESUMEN

Background: Accumulating evidence suggests that N6-methyladenosine (m6A) RNA methylation plays an important role in tumor proliferation and growth. However, its effect on the clinical prognosis, immune infiltration, and immunotherapy response of thyroid cancer patients has not been investigated in detail. Methods: Clinical data and RNA expression profiles of thyroid cancer were extracted from the Cancer Genome Atlas-thyroid carcinoma (TCGA-THCA) and preprocessed for consensus clustering. The risk model was constructed based on differentially expressed genes (DEGs) using Least Absolute Shrinkage and Selection Operator (LASSO) and Cox regression analyses. The associations between risk score and clinical traits, immune infiltration, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Set Enrichment Analysis (GSEA), immune infiltration, and immunotherapy were assessed. Immunohistochemistry was used to substantiate the clinical traits of our samples. Results: Gene expression analysis showed that 17 genes, except YHTDF2, had significant differences (vs healthy control, P<0.001). Consensus clustering yielded 2 clusters according to their clinical features and estimated a poorer prognosis for Cluster 1 (P=0.03). The heatmap between the 2 clusters showed differences in T (P<0.01), N (P<0.001) and stage (P<0.01). Based on univariate Cox and LASSO regression, a risk model consisting of three high-risk genes (KIAA1429, RBM15, FTO) was established, and the expression difference between normal and tumor tissues of three genes was confirmed by immunohistochemical results of our clinical tissues. KEGG and GSEA analyses showed that the risk DEGs were related mainly to proteolysis, immune response, and cancer pathways. The levels of immune infiltration in the high- and low-risk groups were different mainly in iDCs (P<0.05), NK cells (P<0.05), and type-INF-II (P<0.001). Immunotherapy analysis yielded 30 drugs associated with the expression of each gene and 20 drugs associated with the risk score. Conclusions: Our risk model can act as an independent marker for thyroid cancer and provides promising immunotherapy targets for its treatment.


Asunto(s)
Neoplasias de la Tiroides , Humanos , Pronóstico , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/terapia , Ontología de Genes , Inmunoterapia , ARN , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato
16.
Sheng Wu Gong Cheng Xue Bao ; 38(9): 3419-3432, 2022 Sep 25.
Artículo en Chino | MEDLINE | ID: mdl-36151810

RESUMEN

Human fibroblast growth factor 21 (hFGF21) has become a candidate drug for regulating blood glucose and lipid metabolism. The poor stability and short half-life of hFGF21 resulted in low target tissue availability, which hampers its clinical application. In this study, the hFGF21 was fused with a recombinant human serum albumin (HSA), and the resulted fusion protein rHSA-hFGF21 was expressed in Pichia pastoris. After codon optimization, the recombinant gene fragment rHSA-hFGF21 was inserted into two different vectors (pPIC9k and pPICZαA) and transformed into three different strains (X33, GS115 and SMD1168), respectively. We investigated the rHSA-hFGF21 expression levels in three different strains and screened an engineered strain X33-pPIC9K-rHSA-hFGF21 with the highest expression level. To improve the production efficiency of rHSA-hFGF21, we optimized the shake flask fermentation conditions, such as the OD value, methanol concentration and induction time. After purification by hollow fiber membrane separation, Blue affinity chromatography and Q ion exchange chromatography, the purity of the rHSA-hFGF21 protein obtained was 98.18%. Compared to hFGF21, the biostabilities of rHSA-hFGF21, including their resistance to temperature and trypsinization were significantly enhanced, and its plasma half-life was extended by about 27.6 times. Moreover, the fusion protein rHSA-hFGF21 at medium and high concentration showed a better ability to promote glucose uptake after 24 h of stimulation in vitro. In vivo animal studies showed that rHSA-hFGF21 exhibited a better long-term hypoglycemic effect than hFGF21 in type 2 diabetic mice. Our results demonstrated a small-scale production of rHSA-hFGF21, which is important for large-scale production and clinical application in the future.


Asunto(s)
Diabetes Mellitus Experimental , Pichia , Animales , Glucemia/metabolismo , Factores de Crecimiento de Fibroblastos , Humanos , Hipoglucemiantes/metabolismo , Metanol/metabolismo , Ratones , Pichia/genética , Pichia/metabolismo , Proteínas Recombinantes de Fusión , Proteínas Recombinantes/metabolismo , Saccharomycetales , Albúmina Sérica/química , Albúmina Sérica/genética , Albúmina Sérica/metabolismo , Albúmina Sérica Humana/metabolismo
17.
Artículo en Inglés | MEDLINE | ID: mdl-35816530

RESUMEN

Passive upper limb exoskeletons are often designed to relieve muscle fatigue of manufacturing workers. Existing exoskeletons often provide partial assistance, and their assistive torque is only affected by elastic elements and mechanisms, which, however, are not sufficient because of the changing load of the shoulder joint due to the motion of the elbow and the weight of various tools. To improve the assistive effect without affecting the free movement of the arm, a passive exoskeletal vest has been designed. This exoskeleton has two operating states which can be switched using a unique ratchet bar mechanism. The upper arm can be locked at any vertical position when engaged. The assistive torque is determined by the load. The arm also can move freely without any resistance when separated. Seven subjects participated in the evaluation experiment, who performed static tasks, precision tasks, and dynamic tasks. The experimental data demonstrate that (1) the exoskeleton can effectively reduce the activation level of related muscles at a variety of tasks. (2) The accuracy and stability of the arm during heavy work are not affected. (3) The exoskeleton has a minimal restriction on the range of motion of the arm. (4) the comfort and portability achieved a high score of 8 (1-10) from subjective measures. The experimental results further revealed that the designed exoskeletal vest could effectively relieve the shoulder burden, where it does not impede or restrain the arms movements.

18.
Sensors (Basel) ; 22(10)2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35632221

RESUMEN

Calibration and compensation techniques are essential to improve the accuracy of the strap-down inertial navigation system. Especially for the new uniaxial rotation module inertial navigation system (URMINS), replacing faulty uniaxial rotation modules introduces installation errors between modules and reduces navigation accuracy. Therefore, it is necessary to calibrate these systems effectively and compensate for the installation error between modules. This paper proposes a new self-calibration and compensation method for installation errors without additional information and equipment. Using the attitude, velocity, and position differences between the two sets of navigation information output from URMINS as measurements, a Kalman filter is constructed and the installation error is estimated. After URMINS is compensated for the installation error, the average of the demodulated redundant information is taken to calculate the carrier's navigation information. The simulation results show that the proposed method can effectively assess the installation error between modules with an estimation accuracy better than 5". Experimental results for static navigation show that the accuracy of heading angle and positioning can be improved by 73.12% and 81.19% after the URMINS has compensated for the estimated installation errors. Simulation and experimental results further validate the effectiveness of the proposed self-calibration and compensation method.

19.
Micromachines (Basel) ; 13(3)2022 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-35334705

RESUMEN

The traditional temperature modeling method is based on the full heating of the accelerometer to achieve thermal balance, which is not suitable for the cold start-up phase of the micro-accelerometer. For decreasing the complex temperature drift of the cold start-up phase, a new temperature compensation method based on a high-order Fourier transform combined model is proposed. The system structure and repeatability test of the micro digital quartz flexible accelerometer are provided at first. Additionally, we analyzed where the complex temperature drift of the cold start-up phase comes from based on the system structure and repeatability test. Secondly, a high-order temperature compensation model combined with K-means clustering and the symbiotic organisms search (SOS) algorithm is established with repeatability test data as training data. To verify the proposed temperature compensation model, a test platform was built to transmit the measured values before and after compensation with the proposed Fourier-related model and the other time-related model, which is also a model aiming at temperature compensation in the cold start-up phase. The experimental results indicate that the proposed method achieves better compensation accuracy compared with the traditional temperature compensation methods and the time-related compensation model. Furthermore, the compensation for the cold start-up phase has no effect on the original accuracy over the whole temperature range. The stability of the accelerometer can be significantly improved to about 30 µg in the start-up phase of different temperatures after compensation.

20.
Int J Mol Sci ; 23(4)2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35216290

RESUMEN

The aging of mammals is accompanied by the progressive atrophy of tissues and organs and the accumulation of random damage to macromolecular DNA, protein, and lipids. Flavonoids have excellent antioxidant, anti-inflammatory, and neuroprotective effects. Recent studies have shown that flavonoids can delay aging and prolong a healthy lifespan by eliminating senescent cells, inhibiting senescence-related secretion phenotypes (SASPs), and maintaining metabolic homeostasis. However, only a few systematic studies have described flavonoids in clinical treatment for anti-aging, which needs to be explored further. This review first highlights the association between aging and macromolecular damage. Then, we discuss advances in the role of flavonoid molecules in prolonging the health span and lifespan of organisms. This study may provide crucial information for drug design and developmental and clinical applications based on flavonoids.


Asunto(s)
Flavonoides , Longevidad , Envejecimiento/genética , Animales , Senescencia Celular/genética , Flavonoides/farmacología , Flavonoides/uso terapéutico , Donaciones , Promoción de la Salud , Mamíferos
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