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1.
Int J Biol Macromol ; : 133500, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944071

RESUMO

In traditional Chinese medicine, Lycium barbarum is of rich medicinal value, and its polysaccharides are particularly interesting due to their significant pharmacological effects and potential health benefits. This study investigated the immunomodulatory effects of Lycium barbarum polysaccharides (LBPs) by examining their interaction with the TLR4/MD-2 complex and the impacts of gastrointestinal digestion on these interactions. We discovered that the affinity binding of LBPs for TLR4/MD-2 and their cytokine induction capability are influenced by molecular weight, with medium-sized LBPs (100-300 kDa) exhibiting stronger binding affinity and induction capability. Conversely, LBPs smaller than 10 kDa showed reduced activity. Additionally, the content of arabinose and galactose within the LBPs fractions was found to correlate positively with both receptor affinity and cytokine secretion. Simulated gastrointestinal digestion resulted in the degradation of LBPs into smaller fragments that are rich in glucose. Although these fragments exhibited decreased binding affinity to the TLR4/MD-2 complex, they maintained their activity to promote cytokine production. Our findings highlight the significance of molecular weight and specific monosaccharide composition in the immunomodulatory function of LBPs and emphasize the influence of gastrointestinal digestion on the effects of LBPs. This research contributes to a better understanding of the mechanisms underlying the immunomodulatory effects of traditional Chinese medicine polysaccharides and their practical application.

3.
Phytomedicine ; 131: 155784, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38878325

RESUMO

BACKGROUND: Currently, SARS-CoV-2 has not disappeared and continues to prevail worldwide, with the ongoing risk of mutations and the potential for severe COVID-19. The impairment of monocyte mitochondrial function caused by SARS-CoV-2, leading to a metabolic and immune dysregulation, is a crucial factor in the development of severe COVID-19. PURPOSE: Discover effective phytomedicines based on mitochondrial-related biomarkers in severe SARS-CoV-2 infection. METHODS: Firstly, differential gene analysis and gene set enrichment analysis (GSEA) were conducted on monocytes datasets to identify genes and pathways distinguishing severe patients from uninfected individuals. Then, GO and KEGG enrichment analysis on the differentially expressed genes (DEGs) obtained. Take the DEGs and intersect them with the MitoCarta 3.0 gene set to obtain the differentially expressed mitochondrial-related genes (DE-MRGs). Subsequently, machine learning algorithms were employed to screen potential mitochondrial dysfunction biomarkers for severe COVID-19 based on score values. ROC curves were then plotted to assess the distinguish capability of the biomarkers, followed by validation using two additional independent datasets. Next, the effects of the identified biomarkers on metabolic pathways and immune cells were explored through Gene Set Variation Analysis (GSVA) and CIBERSORT. Finally, potential nature products for severe COVID-19 were screened from the expression profile dataset based on dysregulated mitochondrial-related genes, followed by in vitro experimental validation. RESULTS: There are 1812 DEGs and 17 dysregulated mitochondrial processes between severe COVID-19 patients and uninfected individuals. A total of 77 DE-MRGs were identified, and the potential biomarkers were identified as RECQL4, PYCR1, PIF1, POLQ, and GLDC. In both the training and validation sets, the area under the ROC curve (AUC) for these five biomarkers was greater than 0.9. And they did not show significant changes in mild to moderate patients (p > 0.05), indicating their ability to effectively distinguish severe COVID-19. These biomarkers exhibit a highly significant correlation with the dysregulated metabolic processes (p < 0.05) and immune cell imbalance (p < 0.05) in severe patients, as demonstrated by GSVA and CIBERSORT algorithms. Curcumin has the highest score in the predictive model based on transcriptomic data from 496 natural compounds (p = 0.02; ES = 0.90). Pre-treatment with curcumin for 8 h has been shown to alleviate mitochondrial membrane potential damage caused by the SARS-CoV-2 S1 protein (p < 0.05) and reduce elevated levels of reactive oxygen species (ROS) (p < 0.01). CONCLUSION: The results of this study indicate a significant correlation between severe SARS-CoV-2 infection and mitochondrial dysfunction. The proposed mitochondrial dysfunction biomarkers identified in this study are associated with the disease progression, metabolic and immune changes in severe SARS-CoV-2 infected patients. Curcumin has a potential role in preventing severe COVID-19 by protecting mitochondrial function. Our findings provide new strategies for predicting the prognosis and enabling early intervention in SARS-CoV-2 infection.


Assuntos
Biomarcadores , Tratamento Farmacológico da COVID-19 , COVID-19 , Mitocôndrias , Humanos , Biomarcadores/sangue , Mitocôndrias/efeitos dos fármacos , SARS-CoV-2 , Fitoterapia , Aprendizado de Máquina , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Biologia Computacional , Índice de Gravidade de Doença
4.
Sci Bull (Beijing) ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38777682

RESUMO

Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity's exploration of deep space. Over the past decade, the Chinese Lunar Exploration Program (CLEP), also known as the Chang'e (CE) Project, has achieved remarkable milestones. It has successfully developed and demonstrated the engineering capability required to reach and return from the lunar surface. Notably, the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon, along with the collection of the youngest volcanic samples from the Procellarum KREEP Terrane. These achievements have significantly enhanced our understanding of lunar evolution. Building on this success, China has proposed an ambitious crewed lunar exploration strategy, aiming to return to the Moon for scientific exploration and utilization. This plan encompasses two primary phases: the first crewed lunar landing and exploration, followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar surface. Recognizing the limitations of current lunar exploration efforts and China's engineering and technical capabilities, this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic exploration. The study refines fundamental lunar scientific questions that could lead to significant breakthroughs, considering the respective engineering and technological requirements. This research lays a crucial foundation for defining the objectives of future lunar exploration, emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.

5.
Front Comput Neurosci ; 18: 1388083, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659616

RESUMO

Early detection and diagnosis of Autism Spectrum Disorder (ASD) can significantly improve the quality of life for affected individuals. Identifying ASD based on brain functional connectivity (FC) poses a challenge due to the high heterogeneity of subjects' fMRI data in different sites. Meanwhile, deep learning algorithms show efficacy in ASD identification but lack interpretability. In this paper, a novel approach for ASD recognition is proposed based on graph attention networks. Specifically, we treat the region of interest (ROI) of the subjects as node, conduct wavelet decomposition of the BOLD signal in each ROI, extract wavelet features, and utilize them along with the mean and variance of the BOLD signal as node features, and the optimized FC matrix as the adjacency matrix, respectively. We then employ the self-attention mechanism to capture long-range dependencies among features. To enhance interpretability, the node-selection pooling layers are designed to determine the importance of ROI for prediction. The proposed framework are applied to fMRI data of children (younger than 12 years old) from the Autism Brain Imaging Data Exchange datasets. Promising results demonstrate superior performance compared to recent similar studies. The obtained ROI detection results exhibit high correspondence with previous studies and offer good interpretability.

6.
Neuroimage ; 292: 120608, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626817

RESUMO

The morphological analysis and volume measurement of the hippocampus are crucial to the study of many brain diseases. Therefore, an accurate hippocampal segmentation method is beneficial for the development of clinical research in brain diseases. U-Net and its variants have become prevalent in hippocampus segmentation of Magnetic Resonance Imaging (MRI) due to their effectiveness, and the architecture based on Transformer has also received some attention. However, some existing methods focus too much on the shape and volume of the hippocampus rather than its spatial information, and the extracted information is independent of each other, ignoring the correlation between local and global features. In addition, many methods cannot be effectively applied to practical medical image segmentation due to many parameters and high computational complexity. To this end, we combined the advantages of CNNs and ViTs (Vision Transformer) and proposed a simple and lightweight model: Light3DHS for the segmentation of the 3D hippocampus. In order to obtain richer local contextual features, the encoder first utilizes a multi-scale convolutional attention module (MCA) to learn the spatial information of the hippocampus. Considering the importance of local features and global semantics for 3D segmentation, we used a lightweight ViT to learn high-level features of scale invariance and further fuse local-to-global representation. To evaluate the effectiveness of encoder feature representation, we designed three decoders of different complexity to generate segmentation maps. Experiments on three common hippocampal datasets demonstrate that the network achieves more accurate hippocampus segmentation with fewer parameters. Light3DHS performs better than other state-of-the-art algorithms.


Assuntos
Hipocampo , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Redes Neurais de Computação , Aprendizado Profundo , Algoritmos
7.
BMJ Open ; 14(4): e081263, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684277

RESUMO

INTRODUCTION: Type 2 diabetes and non-alcoholic fatty liver disease (NAFLD) often coexist and increase risk for developing liver fibrosis and diabetes complications if no effective measures are taken. Dietary intervention is known to be able to achieve diabetes remission, while evidence regarding the long-term effect on liver fat is limited for comorbidity management of type 2 diabetes and NAFLD. This study aims to investigate the long-term effect of a Chinese Medical Nutrition Therapy (CMNT) diet accompanied by intermittent energy restriction on reducing liver fat and glycated haemoglobin (HbA1c) in patients with type 2 diabetes and NAFLD. METHODS AND ANALYSIS: This is a multicentre two-armed parallel randomised controlled trial study. 120 participants with type 2 diabetes and NAFLD will be recruited from the physical examination centres of multiple hospitals in China. Participants will be randomly allocated 1:1 to either the CMNT group or the usual care group. The CMNT group will be instructed to consume the provided specific meal replacement Chinese medicinal foods consisting of 6 cycles of 5 consecutive days followed by 10 days of regular food intake. The usual care group will be given standard dietary advice. Primary outcomes are changes in the controlled attenuation parameter value by transient elastography and HbA1c level. Secondary outcomes include differences in anthropometrics, clinical blood markers, questionnaires, gut microbiota and metabolomics. Further follow-up will be performed at 6 months, 1 year and 2 years. ETHICS AND DISSEMINATION: The study protocol was approved by the Biomedical Research Ethics Committee of Hunan Agricultural University (BRECHAU20200235).The results will be disseminated via relevant peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT05439226.


Assuntos
Diabetes Mellitus Tipo 2 , Hemoglobinas Glicadas , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Hepatopatia Gordurosa não Alcoólica/terapia , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas/metabolismo , China , Ensaios Clínicos Controlados Aleatórios como Assunto , Terapia Nutricional/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Fígado/metabolismo , Estudos Multicêntricos como Assunto , Técnicas de Imagem por Elasticidade
8.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167149, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38565383

RESUMO

The vascular disrupting agent (VDA) 5,6-dimethylxanthenone-4-acetic acid (DMXAA) induces apoptosis in vascular endothelial cells and leads to tumor hemorrhagic necrosis. While DMXAA has been proven to be a potent agonist of murine stimulator of interferon genes (mSTING), it has little effect on human-STING (hSTING). This species selectivity of DMXAA may explain its effectiveness against solid tumors in mice and its failure in clinical trials. However, DMXAA did reduce tumor volume in some patients during clinical trials. These paradoxical results have prompted us to investigate the anti-tumor mechanism of DMXAA beyond STING in the destruction of tumor vasculature in humans. In this study, we demonstrated that DMXAA binds to both human and mouse macrophage capping protein (CapG), with a KD of 5.839 µM for hCapG and a KD of 2.867 µM for mCapG, as determined by surface plasmon resonance (SPR) analysis. Homology modeling and molecular docking analysis of hCapG indicated that the critical residues involved in the hydrogen bond interaction of DMXAA with hCapG were Arg153, Thr151, and GLN141, Asn234. In addition, electrostatic pi-cation interaction occurred between DMXAA and hCapG. Further functional studies revealed that CapG protein plays a crucial role in the effects of DMXAA on human umbilical endothelial vein cell (HUEVC) angiogenesis and migration, as well as the expression of cytoskeletal proteins actin and tubulin, and the invasion of A549 lung adenocarcinoma cells. Our study has originally uncovered a novel cross-species pathway underlying the antitumor vascular disruption of DMXAA extends beyond STING activation. This finding deepens our understanding of the multifaceted actions of flavonoid VDAs in animal models and in clinical settings, and may provide insights for the precise therapy of DMXAA based on the biomarker CapG protein.


Assuntos
Proteínas de Membrana , Simulação de Acoplamento Molecular , Xantonas , Humanos , Animais , Xantonas/farmacologia , Xantonas/química , Camundongos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química
9.
Sci Rep ; 14(1): 8619, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616200

RESUMO

The joints are existing throughout the underground rock mass. It is of great significance to investigate the shear performance of the rock mass to maintain the stability of the underground structure. In this study, we conducted orthogonal tests to determine the proportion of rock-like materials, and used JRC curves to make specimen molds and then prepare the specimens. We conducted straight shear tests and uniaxial compression tests to determine the various mechanical parameters of the rock-like materials. Next, we carried out the compression and shear tests to investigate the shear characteristics of the specimens, and study the damage pattern and shear strength of the jointed rock mass under different confining pressures and roughness levels. The mesoscopic displacements in the shear process of joints were analyzed by using ABAQUS. The test results show that the effect of the confining pressure on the shear strength of the joint plane is relatively obvious, and a larger confining pressure indicates a larger shear strength. The effects of different joint plane roughness and shear rated on the shear characteristics of the joint plane are also significant. The mesoscopic displacement difference inside the joint plane with higher roughness is relatively large, and the stress concentration phenomenon is obvious and lasts longer, which leads to the faster destruction of the specimen with higher roughness and the higher destruction degree. Therefore, we suggest that the priority should be given to the reinforcement of jointed rock mass with high roughness during the construction to prevent sudden destabilization and failure.

10.
Br J Nutr ; 131(11): 1873-1882, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38343175

RESUMO

Previous studies have revealed an association between dietary factors and atopic dermatitis (AD). To explore whether there was a causal relationship between diet and AD, we performed Mendelian randomisation (MR) analysis. The dataset of twenty-one dietary factors was obtained from UK Biobank. The dataset for AD was obtained from the publicly available FinnGen consortium. The main research method was the inverse-variance weighting method, which was supplemented by MR‒Egger, weighted median and weighted mode. In addition, sensitivity analysis was performed to ensure the accuracy of the results. The study revealed that beef intake (OR = 0·351; 95 % CI 0·145, 0·847; P = 0·020) and white bread intake (OR = 0·141; 95 % CI 0·030, 0·656; P = 0·012) may be protective factors against AD. There were no causal relationships between AD and any other dietary intake factors. Sensitivity analysis showed that our results were reliable, and no heterogeneity or pleiotropy was found. Therefore, we believe that beef intake may be associated with a reduced risk of AD. Although white bread was significant in the IVW analysis, there was large uncertainty in the results given the wide 95 % CI. Other factors were not associated with AD in this study.


Assuntos
Dermatite Atópica , Dieta , Análise da Randomização Mendeliana , Dermatite Atópica/genética , Dermatite Atópica/etiologia , Humanos , Fatores de Risco , Pão , Carne Vermelha/efeitos adversos , Bovinos , Reino Unido/epidemiologia , Animais
11.
Sci Rep ; 14(1): 4783, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413776

RESUMO

To quickly determine the blasting block degree and conduct an accurate and objective analysis of the tunnel blasting effect, this study has enhanced and improved upon the traditional genetic algorithm and Otsu algorithm. It has combined it with the marking watershed method and utilized ground digital acquisition to capture images of blasting debris. These images are then used in our custom-developed blasting analysis software to calculate the blasting block degree distribution and provide a quantitative analysis of blasting block degree. The research results show that the optimized image segmentation algorithm effectively improves the traditional threshold segmentation method on the poor effect of segmentation of the edge of the adherent block or the direct application of the watershed segmentation of the over-segmentation problem, to improve the segmentation accuracy based on the new segmentation technology is close to the traditional technology in terms of time. Through the self-developed software, the construction personnel in the project site to quickly obtain the blasting block degree histogram, block degree cumulative curve and other important indicators of the evaluation of the effect of blasting block degree, to provide data support for on-site construction, to assist in the modification of the blasting program, and to improve the efficiency of construction. This study realizes the rapid detection and block identification of blasting blocks, provides data support for the optimization of blasting parameters, and has good application and promotion value.

12.
Sci Rep ; 14(1): 265, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167851

RESUMO

Earth pressure shields are widely used in tunnel construction due to their low environmental impact and mechanized operations. However, ensuring the stability of the excavation surface during the construction process is crucial. Any instability in the excavation surface can lead to soil destruction, such as body collapse or surface uplift. Additionally, the tunneling process can cause deformation disturbances to nearby buildings. In the case of Beijing Metro Line 17, detailed survey data and construction monitoring data were collected through field surveys and tests. The study combined theoretical analysis and numerical simulations to investigate the impact of shield tunneling in clay layers on neighboring buildings. The focus was on analyzing the physical deformation and the response law of influencing factors, such as stratum parameters and engineering effects on surface settlement, building inclination, and distortion. Furthermore, sensitivity analysis of the deformation impact was conducted, and corresponding measures for deformation control were proposed.

13.
Int J Biol Macromol ; 261(Pt 1): 129785, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38286372

RESUMO

Viral respiratory infections are major human health concerns. The most striking epidemic disease, COVID-19 is still on going with the emergence of fast mutations and drug resistance of pathogens. A few polysaccharide macromolecules from traditional Chinese medicine (TCM) have been found to have direct anti-SARS-CoV-2 activity but the mechanism remains unclear. In this study, we evaluated the entry inhibition effect of Lycium barbarum polysaccharides (LBP) in vitro and in vivo. We found LBP effectively suppressed multiple SARS-CoV-2 variants entry and protected K18-hACE2 mice from invasion with Omicron pseudovirus (PsV). Moreover, we found LBP interfered with early entry events during infection in time-of-addition (TOA) assay and SEM observation. Further surface plasmon resonance (SPR) study revealed the dual binding of LBP with Spike protein and ACE2, which resulted in the disruption of Spike-ACE2 interaction and subsequently triggered membrane fusion. Therefore, LBP may act as broad-spectrum inhibitors of virus entry and nasal mucosal protective agent against newly emerging respiratory viruses, especially SARS-CoV-2.


Assuntos
COVID-19 , Lycium , Humanos , Animais , Camundongos , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2 , Glicoproteína da Espícula de Coronavírus , Ligação Proteica
14.
Neuro Endocrinol Lett ; 44(4): 193-198, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37466058

RESUMO

OBJECTIVE: Research has shown that hydrogen sulfide (H2S) plays a protective role in many diseases of the nervous system. The aim of this study is to investigate the effect of hypoxia on endogenous H2S concentration in the cerebral cortex of Alzheimer's disease (AD) transgenic mice and its mechanism. METHODS: AD transgenic mice were raised in closed boxes and pure nitrogen was introduced to reduce the oxygen concentration to 8%-10%, establishing an animal model of hypoxia. Oxygen partial pressure was measured with an oxygen meter. The expression of cystathionine-ß-synthase (CBS) in cerebral cortex tissue was determined by Western blot, and H2S concentration was measured by a modified methylene blue method. RESULTS: (1) Hypoxia down-regulated CBS expression in cerebral cortex tissue of AD transgenic mice (p < 0.05). (2) The concentration of H2S in the cerebral cortex tissue of the hypoxic transgenic group was significantly lower than that of the Control group (p < 0.01). (3) Overexpression of CBS reversed the hypoxia-induced decrease of H2S concentration in the cerebral cortex tissue of AD transgenic mice (p < 0.01). CONCLUSIONS: Hypoxia decreased the concentration of endogenous H2S in the cerebral cortex tissue of AD transgenic mice by down-regulating the expression of CBS.


Assuntos
Doença de Alzheimer , Sulfeto de Hidrogênio , Camundongos , Animais , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Doença de Alzheimer/genética , Camundongos Transgênicos , Encéfalo/metabolismo , Hipóxia/metabolismo , Oxigênio/metabolismo , Oxigênio/farmacologia
15.
Anat Sci Educ ; 16(6): 1200-1208, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37328430

RESUMO

In recent years, China has been facing a shortage of cadavers for teaching medical students. A better comprehension of the attitudes and factors influencing the general public's opinion toward body donation would be invaluable for planning and implementing body donation programs. Although altruistic attitude and attitudes toward death have received considerable attention in recent years globally, they have been largely understudied in China. Herein, the potential relationship between attitudes toward altruism and death, and willingness toward whole-body donation in a sample of university students in Changsha City in China were analyzed. A multi-stage sampling method was adopted to recruit 478 Chinese college students from two universities: the Medical College of Hunan Normal University (n = 272) and the College of Civil engineering of Hunan University (n = 206). The study participants were assessed by a sociodemographic questionnaire, the Death Attitude Profile-Revised (DAP-R-C) questionnaire, and the altruism scale. Moreover, Chinese University students demonstrated moderate willingness to donate their bodies. The mean score of the willingness of study participants to donate their bodies was 3.138 ± 0.933 (5-point Likert scale). Acceptance toward death, gender, and type of university were positive factors, whereas fear of death negatively affected willingness toward body donation. Regression analysis showed that factors, including gender (ß = 0.237), type of university (ß = 0.193), natural acceptance (ß = 0.177), and fear of death (ß = -0.160) influenced willingness toward body donation. Overall, the present study provides hitherto undocumented evidence on factors influencing willingness toward body donation among Chinese university students, which can assist in designing public awareness programs for encouraging body donation.


Assuntos
Anatomia , Estudantes de Medicina , Obtenção de Tecidos e Órgãos , Humanos , Altruísmo , Anatomia/educação , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , China , Doadores de Tecidos
16.
Nat Commun ; 14(1): 3734, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37349323

RESUMO

The history of mare volcanism critically informs the thermal evolution of the Moon. However, young volcanic eruptions are poorly constrained by remote observations and limited samples, hindering an understanding of mare eruption flux over time. The Chang'e-5 mission returned the youngest lunar basalts thus far, offering a window into the Moon's late-stage evolution. Here, we investigate the mineralogy and geochemistry of 42 olivine and pyroxene crystals from the Chang'e-5 basalts. We find that almost all of them are normally zoned, suggesting limited magma recharge or shallow-level assimilation. Most olivine grains record a short timescale of cooling. Thermal modeling used to estimate the thickness and volume of the volcanism sampled by Chang'e-5 reveals enhanced magmatic flux ~2 billion years ago, suggesting that while overall lunar volcanic activity may decrease over time, episodic eruptions at the final stage could exhibit above average eruptive fluxes, thus revising models of lunar thermal evolution.


Assuntos
Lua , Temperatura Baixa
17.
Front Neurosci ; 17: 1134176, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152609

RESUMO

A substantial body of evidence has indicated that intracerebral O-linked N-acetyl-ß-D-glucosamine (O-GlcNAc), a generalized post-translational modification, was emerging as an effective regulator of stress-induced emotional and cognitive impairments. Our previous studies showed that the Liuwei Dihuang formula (LW) significantly improved the emotional and cognitive dysfunctions in various types of stress mouse models. In the current study, we sought to determine the effects of LW on intracerebral O-GlcNAc levels in chronic unpredictable mild stress (CUMS) mice. The dynamic behavioral tests showed that anxiety- and depression-like behaviors and object recognition memory of CUMS mice were improved in a dose-dependent manner after LW treatment. Moreover, linear discriminate analysis (LEfSe) of genera abundance revealed a significant difference in microbiome among the study groups. LW showed a great impact on the relative abundance of these gut microbiota in CUMS mice and reinstated them to control mouse levels. We found that LW potentially altered the Uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc) biosynthesis process, and the abundance of O-GlcNAcase (OGA) and O-GlcNAc transferase (OGT) in CUMS mice, which was inferred using PICRUSt analysis. We further verified advantageous changes in hippocampal O-GlcNAc modification of CUMS mice following LW administration, as well as changes in the levels of OGA and OGT. In summary, LW intervention increased the levels of hippocampal O-GlcNAc modification and ameliorated the emotional and cognitive impairments induced by chronic stress in CUMS mice. LW therefore could be considered a potential prophylactic and therapeutic agent for chronic stress.

18.
Int J Biol Sci ; 19(8): 2588-2598, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215996

RESUMO

Excessive stress leads to disruptions of the central nervous system. Individuals' responses to stress and trauma differ from person to person. Some may develop various neuropsychiatric disorders, such as post-traumatic stress disorder, major depression, and anxiety disorders, while others may successfully adapt to the same stressful events. These two neural phenotypes are called susceptibility and resilience. Previous studies have suggested resilience/susceptibility as a complex, non-specific systemic response involving central and peripheral systems. Emerging research of mechanisms underlying resilience is mostly focussing on the physiological adaptation of specific brain circuits, neurovascular impairment of the blood-brain barrier, the role of innate and adaptive factors of the immune system, and the dysbiosis of gut microbiota. In accordance with the microbiota-gut-brain axis hypothesis, the gut microbiome directly influences the interface between the brain and the periphery to affect neuronal function. This review explored several up-to-date studies on the role of gut microbiota implicated in stressful events-related resilience/susceptibility. We mainly focus on the changes in behavior and neuroimaging characteristics, involved brain regions and circuits, the blood-brain barrier, the immune system, and epigenetic modifications, which contribute to stress-induced resilience and susceptibility. The perspective of the gut-brain axis could help to understand the mechanisms underlying resilience and the discovery of biomarkers may lead to new research directions and therapeutic interventions for stress-induced neuropsychiatric disorders.


Assuntos
Microbioma Gastrointestinal , Microbioma Gastrointestinal/fisiologia , Encéfalo/fisiologia , Barreira Hematoencefálica
19.
Nat Commun ; 14(1): 1173, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859491

RESUMO

Impact ejecta are important references to establish regional and global stratigraphy of planetary bodies. Canonical views advocate radial distributions of distal ejecta with respect to the source crater, and their trajectories are significantly deflected on fast-rotating bodies. The Hokusai crater on Mercury formed a peculiar ray that features a hyperbola shape, and the sharp swerve of orientation was interpreted as a sign of a faster planetary rotation in the near past. Here, we show that this ray was not caused by a hypothesized larger Coriolis force, but due to abruptly-steepened ejection angles. Heterogeneous shock impedances of pre-impact impactor and/or target, such as topographic undulations, affect local propagation paths of shock and rarefaction waves, causing sudden changes of ejection angles. Distal ejecta with non-radial distributions are an inherent product of planetary impacts, and their unobvious provenances could mislead stratigraphic interpretations and hamper age estimations based on spatial densities of impact craters.

20.
J Integr Med ; 21(2): 136-148, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36635165

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is the primary cause of anovulatory infertility, bringing serious harm to women's physical and mental health. Acupuncture may be an effective treatment for PCOS. However, systematic reviews (SRs) on the efficacy and safety of acupuncture for PCOS have reported inconsistent results, and the quality of these studies has not been adequately assessed. OBJECTIVE: To summarize and evaluate the current evidence on the efficacy and safety of acupuncture for PCOS, as well as to assess the quality and risks of bias of the available SRs. SEARCH STRATEGY: Nine electronic databases (Cochrane Library, MEDLINE, Embase, PsycINFO, CINAHL, Chinese National Knowledge Infrastructure, Wanfang Data, Chongqing VIP Chinese Science and Technology Periodical Database, and China Biology Medicine disc) were searched from their establishment to July 27, 2022. Based on the principle of combining subject words with text words, the search strategy was constructed around search terms for "acupuncture," "polycystic ovary syndrome," and "systematic review." INCLUSION CRITERIA: SRs of randomized controlled trials that explored the efficacy and (or) safety of acupuncture for treating patients with PCOS were included. DATA EXTRACTION AND ANALYSIS: Two authors independently extracted study data according to a predesigned form. Tools for evaluating the methodological quality, risk of bias, reporting quality, and confidence in study outcomes, including A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2), Risk of Bias in Systematic Reviews (ROBIS), Preferred Reporting Items for Systematic Reviews and Meta-analyses for Acupuncture (PRISMA-A), and the Grading of Recommendations Assessment, Development and Evaluation (GRADE), were used to score the included SRs. RESULTS: A total of 885 studies were retrieved, and 11 eligible SRs were finally included in this review. The methodological quality of 2 SRs (18.18%) was low, while the other 9 SRs (81.82%) were scored as extremely low. Four SRs (36.36%) were considered to be of low risk of bias. As for reporting quality, the reporting completeness of 9 SRs (81.82%) was more than 70%. Concerning the confidence in study results, 2 study results were considered to have a high quality of evidence (3.13%), 14 (21.88%) a "moderate" quality, 28 (43.75%) a "low" quality, and 20 (31.24%) considered a "very low" quality. Descriptive analyses suggested that combining acupuncture with other medicines can effectively improve the clinical pregnancy rate (CPR) and ovulation rate, and reduce luteinizing hormone/follicle-stimulating hormone ratio, homeostasis model assessment of insulin resistance, and body mass index (BMI). When compared with medicine alone, acupuncture alone also can improve CPR. Further, when compared with no intervention, acupuncture had a better effect in promoting the recovery of menstrual cycle and reducing BMI. Acupuncture was reported to cause no adverse events or some adverse events without serious harm. CONCLUSION: The efficacy and safety of acupuncture for PCOS remains uncertain due to the limitations and inconsistencies of current evidence. More high-quality studies are needed to support the use of acupuncture in PCOS.


Assuntos
Terapia por Acupuntura , Infertilidade Feminina , Síndrome do Ovário Policístico , Gravidez , Humanos , Feminino , Síndrome do Ovário Policístico/terapia , Síndrome do Ovário Policístico/etiologia , Terapia por Acupuntura/efeitos adversos , Infertilidade Feminina/tratamento farmacológico , Infertilidade Feminina/etiologia , China
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