Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
iScience ; 27(5): 109617, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38660401

RESUMO

Long-term manned spaceflight and extraterrestrial planet settlement become the focus of space powers. However, the potential influence of closed and socially isolating spaceflight on the brain function remains unclear. A 180-day controlled ecological life support system integrated experiment was conducted, establishing a spaceflight analog environment to explore the effect of long-term socially isolating living. Three crewmembers were enrolled and underwent resting-state fMRI scanning before and after the experiment. We performed both seed-based and network-based analyses to investigate the functional connectivity (FC) changes of the default mode network (DMN), considering its key role in multiple higher-order cognitive functions. Compared with normal controls, the leader of crewmembers exhibited significantly reduced within-DMN and between-DMN FC after the experiment, while two others exhibited opposite trends. Moreover, individual differences of FC changes were further supported by evidence from behavioral analyses. The findings may shed new light on the development of psychological protection for space exploration.

2.
Plant Commun ; : 100922, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38616490

RESUMO

Proper timing for plants to flower under different environmental conditions is critical for their propagation. Light quality is a pivotal environmental cue that plays a critical role in regulating flowering. Plants tend to flower late under light with high red (R)/far-red (FR) light ratio, whereas flower early under light with a low R/FR light ratio. However, how plants fine-tune flowering in response to changes in light quality is not well understood. Here, we demonstrate that the F-box Protein F-box of Flowering 2 (FOF2), an autonomous pathway-related regulator, physically interacts with VASCULAR PLANT ONE-ZINC FINGER 1 and 2 (VOZ1 and VOZ2), which are the direct downstream factors of R/FR light receptor phytochrome B (PHYB). Furthermore, we show that PHYB physically interacts with FOF2 and mediates FR light and end-of-day far-red light (EOD-FR) stabilization of the FOF2 protein and enhances FOF2 binding to VOZ2, leading to VOZ2 protein degradation by SCFFOF2 E3 ligase. In contrast, PHYB mediates R light and end-of-day red light (EOD-R) degradation of FOF2 protein. Genetic interaction studies demonstrate that FOF2 functions downstream of PHYB to promote FLC expression and inhibit flowering under both high R/FR light and simulated shade conditions, which partially depend on VOZ proteins. Taken together, our findings suggest a novel mechanism whereby plants fine-tune flowering time through PHYB-FOF2-VOZ2 module that modulates FLC expression in response to changes in light quality.

3.
Signal Transduct Target Ther ; 9(1): 86, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584163

RESUMO

During spaceflight, the cardiovascular system undergoes remarkable adaptation to microgravity and faces the risk of cardiac remodeling. Therefore, the effects and mechanisms of microgravity on cardiac morphology, physiology, metabolism, and cellular biology need to be further investigated. Since China started constructing the China Space Station (CSS) in 2021, we have taken advantage of the Shenzhou-13 capsule to send human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) to the Tianhe core module of the CSS. In this study, hPSC-CMs subjected to space microgravity showed decreased beating rate and abnormal intracellular calcium cycling. Metabolomic and transcriptomic analyses revealed a battery of metabolic remodeling of hPSC-CMs in spaceflight, especially thiamine metabolism. The microgravity condition blocked the thiamine intake in hPSC-CMs. The decline of thiamine utilization under microgravity or by its antagonistic analog amprolium affected the process of the tricarboxylic acid cycle. It decreased ATP production, which led to cytoskeletal remodeling and calcium homeostasis imbalance in hPSC-CMs. More importantly, in vitro and in vivo studies suggest that thiamine supplementation could reverse the adaptive changes induced by simulated microgravity. This study represents the first astrobiological study on the China Space Station and lays a solid foundation for further aerospace biomedical research. These data indicate that intervention of thiamine-modified metabolic reprogramming in human cardiomyocytes during spaceflight might be a feasible countermeasure against microgravity.


Assuntos
Células-Tronco Pluripotentes , Ausência de Peso , Humanos , 60645 , Miócitos Cardíacos/metabolismo , Cálcio/metabolismo , Diferenciação Celular , Células-Tronco Pluripotentes/metabolismo
4.
NPJ Microgravity ; 10(1): 9, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233425

RESUMO

The elevation in the optic nerve sheath (ONS) pressure (ONSP) due to microgravity-induced headward fluid shift is the primary hypothesized contributor to SANS. This longitudinal study aims to quantify the axial plane of the optic nerve subarachnoid space area (ONSSA), which is filled with cerebrospinal fluid (CSF) and expands with elevated ONSP during and after head-down tilt (HDT) bed rest (BR). 36 healthy male volunteers (72 eyes) underwent a 90-day strict 6° HDT BR. Without obtaining the pre-HDT data, measurements were performed on days 30, 60, and 90 during HDT and at 6 recovery time points extended to 180-days (R + 180) in a supine position. Portable B-scan ultrasound was performed using the 12 MHz linear array probe binocularly. The measurements of the ONS and the calculation of the ONSSA were performed with ImageJ 1.51 analysis software by two experienced observers in a masked manner. Compared to R + 180, the ONSSA on HDT30, HDT60, and HDT90 exhibited a consistently significant distention of 0.44 mm2 (95% CI: 0.13 to 0.76 mm2, P = 0.001), 0.45 mm2 (95% CI: 0.15 to 0.75 mm2, P = 0.001), and 0.46 mm2 (95% CI: 0.15 to 0.76 mm2, P < 0.001), respectively, and recovered immediately after HDT on R + 2. Such small changes in the ONSSA were below the lateral resolution limit of ultrasound (0.4 mm) and may not be clinically relevant, possibly due to ONS hysteresis causing persistent ONS distension. Future research can explore advanced quantitative portable ultrasound-based techniques and establish comparisons containing the pre-HDT measurements to deepen our understanding of SANS.

5.
ACS Appl Bio Mater ; 6(3): 1260-1271, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36884222

RESUMO

Hypoglycemia state damages the organism, and glucose-excited and glucose-inhibited neurons from the ventral medial hypothalamus can regulate this state. Therefore, it is crucial to understand the functional mechanism between blood glucose and electrophysiology of glucose-excited and glucose-inhibited neurons. To better detect and analyze this mechanism, a PtNPs/PB nanomaterials modified 32-channel microelectrode array with low impedance (21.91 ± 6.80 kΩ), slight phase delay (-12.7° ± 2.7°), high double layer capacitance (0.606 µF), and biocompatibility was developed to realize in vivo real-time detection of the electrophysiology activities of glucose-excited and glucose-inhibited neurons. The phase-locking level of some glucose-inhibited neurons elevated during fasting (low blood glucose state) and showed theta rhythms after glucose injection (high blood glucose state). With an independent oscillating ability, glucose-inhibited neurons can provide an essential indicator to prevent severe hypoglycemia. The results reveal a mechanism for glucose-sensitive neurons to respond to blood glucose. Some glucose-inhibited neurons can integrate glucose information input and convert it into theta oscillating or phase lock output. It helps in enhancing the interaction between neurons and glucose. Therefore, the research can provide a basis for further controlling blood glucose by modulating the characteristics of neuronal electrophysiology. This helps reduce the damage of organisms under energy-limiting conditions, such as prolonged manned spaceflight or metabolic disorders.


Assuntos
Hipoglicemia , Nanocompostos , Humanos , Glucose/farmacologia , Glicemia/metabolismo , Microeletrodos , Neurônios/metabolismo , Hipoglicemia/diagnóstico , Hipoglicemia/metabolismo
6.
Genes (Basel) ; 14(1)2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36672905

RESUMO

The GRAS transcription factor is an important transcription factor in plants. In recent years, more GRAS genes have been identified in many plant species. However, the GRAS gene family has not yet been studied in Avena sativa. We identified 100 members of the GRAS gene family in A. sativa (Avena sativa), named them AsGRAS1~AsGRAS100 according to the positions of 21 chromosomes, and classified them into 9 subfamilies. In this study, the motif and gene structures were also relatively conserved in the same subfamilies. At the same time, we found a great deal related to the stress of cis-acting promoter regulatory elements (MBS, ABRE, and TC-rich repeat elements). qRT-PCR suggested that the AsGRAS gene family (GRAS gene family in A. sativa) can regulate the response to salt, saline-alkali, and cold and freezing abiotic stresses. The current study provides original and detailed information about the AsGRAS gene family, which contributes to the functional characterization of GRAS proteins in other plants.


Assuntos
Avena , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Avena/genética , Avena/metabolismo , Genoma de Planta , Filogenia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
New Phytol ; 237(3): 840-854, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36305219

RESUMO

Light is a particularly important environmental cue that regulates a variety of diverse plant developmental processes, such as photomorphogenesis. Blue light promotes photomorphogenesis mainly through the activation of the photoreceptor cryptochrome 1 (CRY1). However, the mechanism underlying the CRY1-mediated regulation of growth is not fully understood. Here, we found that blue light induced N6 -methyladenosine (m6 A) RNA modification during photomorphogenesis partially via CRY1. Cryptochrome 1 mediates blue light-induced expression of FKBP12-interacting protein 37 (FIP37), which is a component of m6 A writer. Moreover, we showed that CRY1 physically interacted with FIP37 in vitro and in vivo, and mediated blue light activation of FIP37 binding to RNA. Furthermore, CRY1 and FIP37 modulated m6 A on photomorphogenesis-related genes PIF3, PIF4, and PIF5, thereby accelerating the decay of their transcripts. Genetically, FIP37 repressed hypocotyl elongation under blue light, and fip37 mutation could partially rescue the short-hypocotyl phenotype of CRY1-overexpressing plants. Together, our results provide a new insight into CRY1 signal in modulating m6 A methylation and stability of PIFs, and establish an essential molecular link between m6 A modification and determination of photomorphogenesis in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Criptocromos/genética , Criptocromos/metabolismo , Regulação da Expressão Gênica de Plantas , Hipocótilo/metabolismo , Luz , RNA/metabolismo , Proteína 1A de Ligação a Tacrolimo/genética , Proteína 1A de Ligação a Tacrolimo/metabolismo , Fatores de Transcrição/metabolismo
8.
Antioxidants (Basel) ; 11(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36552574

RESUMO

Senile and disuse osteoporosis have distinct bone turnover status and lack effective treatments. In this study, senescence-accelerated mouse prone 8 (SAMP8) and hindlimb unloading mouse models were used to explore the protective effects of daphnetin on these two types of osteoporosis, and primary osteoblasts and bone marrow monocyte-derived osteoclasts, as well as pre-osteoblast MC3T3-E1, and osteoclast precursor RAW264.7 cells were used to investigate the underlying mechanisms. The results showed that daphnetin administration effectively improved bone remodeling in both senile and disuse osteoporosis, but with different mechanisms. In senile osteoporosis with low bone turnover, daphnetin inhibited NOX2-mediated ROS production in osteoblasts, resulting in accelerated osteogenic differentiation and bone formation, while in disuse osteoporosis with high bone turnover, daphnetin restored SIRT3 expression, maintained mitochondrial homeostasis, and additionally upregulated SOD2 to eliminate ROS in osteoclasts, resulting in attenuation of osteoclast differentiation and bone resorption. These findings illuminated that daphnetin has promising potential for the prevention and treatment of senile and disuse osteoporosis. The different mechanisms may provide clues and basis for targeted prevention and treatment of osteoporosis according to distinct bone turnover status.

9.
Gastroenterol Res Pract ; 2022: 4313647, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304789

RESUMO

Background: Magnetically controlled capsule endoscopy has been shown to be feasible for the examination of gastric diseases. However, there may be problems, such as low image quality, incomplete esophageal observation, and capsule retention. We developed a novel magnetically controlled cable capsule endoscopy (MCCCE) system and evaluated its feasibility through in vitro experiments. Methods: Three experienced endoscopists performed MCCCE on the plastic stomach model and the excised porcine stomach model 5 times, respectively. Outcomes included handle ability, examination time, examination completion, and image quality. The examination completion was accessed by other two blinded endoscopists, and the image quality was compared with conventional gastroscopy (Olympus, GIF-290). Results: The performance of MCCCE in vitro experiments is excellent, with a mean operation time of 18.5 minutes in the plastic stomach model and 17.3 minutes in the excised porcine stomach model. The visualization rate of the gastric mucosa is >90% in the plastic stomach model and 75-90% in the excised porcine stomach model. The images of MCCCE are very clear, with good color resolution and no image distortion, which seem to be comparable to conventional gastroscopy. Conclusions: MCCCE system is feasible for gastric examination in vitro experiments, living animal experiments and human trials need to be further conducted.

10.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36198665

RESUMO

As space exploration programs progress, manned space missions will become more frequent and farther away from Earth, putting a greater emphasis on astronaut health. Through the collaborative efforts of researchers from various countries, the effect of the space environment factors on living systems is gradually being uncovered. Although a large number of interconnected research findings have been produced, their connection seems to be confused, and many unknown effects are left to be discovered. Simultaneously, several valuable data resources have emerged, accumulating data measuring biological effects in space that can be used to further investigate the unknown biological adaptations. In this review, the previous findings and their correlations are sorted out to facilitate the understanding of biological adaptations to space and the design of countermeasures. The biological effect measurement methods/data types are also organized to provide references for experimental design and data analysis. To aid deeper exploration of the data resources, we summarized common characteristics of the data generated from longitudinal experiments, outlined challenges or caveats in data analysis and provided corresponding solutions by recommending bioinformatics strategies and available models/tools.


Assuntos
Disciplinas das Ciências Biológicas , Voo Espacial , Biologia Computacional
11.
Front Physiol ; 13: 902983, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36117704

RESUMO

Spaceflight is associated with enhanced inactivity, resulting in muscular and cardiovascular deconditioning. Although physical exercise is commonly used as a countermeasure, separate applications of running and resistive exercise modalities have never been directly compared during long-term bedrest. This study aimed to compare the effectiveness of two exercise countermeasure programs, running and resistance training, applied separately, for counteracting cardiovascular deconditioning induced by 90-day head-down bedrest (HDBR). Maximal oxygen uptake ( V ˙ O2max), orthostatic tolerance, continuous ECG and blood pressure (BP), body composition, and leg circumferences were measured in the control group (CON: n = 8), running exercise group (RUN: n = 7), and resistive exercise group (RES: n = 7). After HDBR, the decrease in V ˙ O2max was prevented by RUN countermeasure and limited by RES countermeasure (-26% in CON p < 0.05, -15% in RES p < 0.05, and -4% in RUN ns). Subjects demonstrated surprisingly modest orthostatic tolerance decrease for different groups, including controls. Lean mass loss was limited by RES and RUN protocols (-10% in CON vs. -5% to 6% in RES and RUN). Both countermeasures prevented the loss in thigh circumference (-7% in CON p < 0.05, -2% in RES ns, and -0.6% in RUN ns) and limited loss in calf circumference (-10% in CON vs. -7% in RES vs. -5% in RUN). Day-night variations in systolic BP were preserved during HDBR. Decrease in V ˙ O2max positively correlated with decrease in thigh (r = 0.54 and p = 0.009) and calf (r = 0.52 and p = 0.012) circumferences. During this 90-day strict HDBR, running exercise successfully preserved V ˙ O2max, and resistance exercise limited its decline. Both countermeasures limited loss in global lean mass and leg circumferences. The V ˙ O2max reduction seems to be conditioned more by muscular than by cardiovascular parameters.

12.
Surg Endosc ; 36(12): 9454-9461, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36112221

RESUMO

BACKGROUND: Magnetically controlled capsule endoscopy (MCCE) has recently increasingly been used for gastric examination. However, the image quality and esophageal observation is suboptimal. We developed a novel wired transmission magnetically controlled capsule endoscopy (WT-MCCE) system and evaluated its feasibility through in vitro and in vivo experiments. METHODS: A plastic stomach model and a pathological upper gastrointestinal model were used to evaluate the performance of WT-MCCE in vitro experiments. Twice of examination in the two in vitro models by WT-MCCE were performed by 5 endoscopists who were experienced in performing wireless capsule endoscopy. The examination of traditional gastroscopy (Olympus, GIF-HQ290) in the pathological upper gastrointestinal model was set as the control. In vivo experiments were performed in a live canine model by 3 endoscopists, in which WT-MCCE was inserted with the assistance of gastroscopy. Measurements included maneuverability, examination time, visualization of gastric mucosa, image quality and diagnostic accuracy. RESULTS: WT-MCCE showed good performance in both in vitro and in vivo experiments with excellent visualization of mucosa (75-100%). The mean operation time is 17.6 ± 2.7 min, 22.3 ± 1.9 min and 29.3 ± 3.4 min in three models, respectively. In pathological upper gastrointestinal model, all lesions, including esophageal varices, one polyp, one foreign body, two gastric ulcers and one duodenal ulcer, were detected by both WT-MCCE and traditional gastroscopy by all endoscopists. For the observation of esophagus and stomach in the canine model, WT-MCCE also showed excellent maneuverability and good image quality. CONCLUSIONS: The novel WT-MCCE system performed well in evaluating upper gastrointestinal landmarks and lesions in two in vitro models, and showed good performance in a canine model. WT-MCCE may be potentially useful for diagnosis of esophageal and gastric diseases.


Assuntos
Endoscopia por Cápsula , Úlcera Gástrica , Trato Gastrointestinal Superior , Cães , Animais , Endoscopia do Sistema Digestório/métodos , Gastroscopia/métodos , Trato Gastrointestinal Superior/diagnóstico por imagem
13.
Contrast Media Mol Imaging ; 2022: 7181258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909582

RESUMO

To evaluate the clinical effect of ornidazole mixture in auxiliary filling of patients with endodontic disease. A total of 124 patients with endodontic diseases admitted to our hospital from January 2020 to December 2021 were included and divided into two groups according to the random number table. The observation group (n = 62) was given ornidazole mixture-assisted filling, while the control group (n = 62) was given pulp mummification filling to evaluate its application effect. Compared with the control group, the disappearance time of tooth hyperesthesia, gingival redness, and pain symptoms in the observation group were significantly shorter and the difference had statistical significance (P < 0.05); the excellent and good rate of the observation group was 96.77% and 85.48%, respectively, and the difference had statistical significance (P < 0.05); the masticatory efficiency, occlusal force, and oral health-related quality of life scores in the observation group were higher than those in the control group after treatment, and the difference had statistical significance (P < 0.05). Ornidazole mixture can promote the curative effect, shorten the time of symptom disappearance, and effectively improve the masticatory function and quality of life in patients with endodontic diseases.


Assuntos
Ornidazol , Humanos , Ornidazol/efeitos adversos , Ornidazol/uso terapêutico , Qualidade de Vida
14.
ACS Omega ; 7(29): 25380-25393, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35910109

RESUMO

A new cement-based sealing material, which used Portland cement (PC) as a raw material and supplemented several gel components, such as accelerant, alkali activator, suspension agent, expansion agent, reinforcing agent, was prepared in this work. The effects of these components on the fluidity, setting time, and expansion rate of these sealing materials were investigated by an orthogonal test. The results show that the water-cement ratio and the reinforcing agent content, the accelerant content and the water-cement ratio, and the expansion agent content and the accelerant content are the most important influencing factors on fluidity, setting time, and expansion rate, respectively. In addition, the regression models and response surfaces of the factors were established using a multiple linear regression method. By this means, the influences of the two main factors on each performance of this sealing material were accurately and intuitively reflected for obtaining the optimal value in the optimization area. The results indicate that the sealing materials possess the best performances when the water-cement ratio is 1.1, the accelerant content is 50%, the expansion agent content is 0.1%, and the reinforcing agent content is 3%, which is corresponding to a fluidity of 360-380 mm, an initial (final) setting time of 60 (80)-80 (100) min, and an expansion rate of 2-12%. Furthermore, the microstructures of the optimized sealing material also reveal that the main hydration products of PC are transformed from layered Ca(OH)2 crystals into fine needle-like AFt crystals and C-S-H gels by the promotion effect of the optimizing ratio, thus leading to a more compact structure of optimized cement-based sealing materials.

15.
Stem Cell Res Ther ; 13(1): 239, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672803

RESUMO

BACKGROUND: Endothelial cells are located in the inner lumen of blood and lymphatic vessels and exhibit the capacity to form new vessel branches from existing vessels through a process called angiogenesis. This process is energy intensive and tightly regulated. Glycolysis is the main energy source for angiogenesis. Retinoic acid (RA) is an active metabolite of vitamin A and exerts biological effects through its receptor retinoic acid receptor (RAR). In the clinic, RA is used to treat acne vulgaris and acute promyelocytic leukemia. Emerging evidence suggests that RA is involved in the formation of the vasculature; however, its effect on endothelial cell angiogenesis and metabolism is unclear. METHODS: Our study was designed to clarify the abovementioned effect with human embryonic stem cell-derived endothelial cells (hESC-ECs) employed as a cell model. RESULTS: We found that RA inhibits angiogenesis, as manifested by decreased proliferation, migration and sprouting activity. RNA sequencing revealed general suppression of glycometabolism in hESC-ECs in response to RA, consistent with the decreased glycolytic activity and glucose uptake. After screening glycometabolism-related genes, we found that fructose-1,6-bisphosphatase 1 (FBP1), a key rate-limiting enzyme in gluconeogenesis, was significantly upregulated after RA treatment. After silencing or pharmacological inhibition of FBP1 in hESC-ECs, the capacity for angiogenesis was enhanced, and the inhibitory effect of RA was reversed. ChIP-PCR demonstrated that FBP1 is a target gene of RAR. When hESC-ECs were treated with the RAR inhibitor BMS493, FBP1 expression was decreased and the effect of RA on angiogenesis was partially blocked. CONCLUSIONS: The inhibitory role of RA in glycometabolism and angiogenesis is RAR/FBP1 dependent, and FBP1 may be a novel therapeutic target for pathological angiogenesis.


Assuntos
Células-Tronco Embrionárias Humanas , Tretinoína , Células Endoteliais/metabolismo , Frutose , Gluconeogênese/genética , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Neovascularização Patológica , Tretinoína/farmacologia
16.
PLoS One ; 17(3): e0265108, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35271667

RESUMO

A large number of aerospace practices have confirmed that the aerospace microgravity environment can lead to cognitive function decline. Mitochondria are the most important energy metabolism organelles, and some studies demonstrate that the areospace microgravity environment can cause mitochondrial dysfunction. However, the relationships between cognitive function decline and mitochondrial dysfunction in the microgravity environment have not been elucidated. In this study, we simulated the microgravity environment in the Sprague-Dawley (SD) rats by -30° tail suspension for 28 days. We then investigated the changes of mitochondrial morphology and proteomics in the hippocampus. The electron microscopy results showed that the 28-day tail suspension increased the mitochondria number and size of rat hippocampal neuronal soma. Using TMT-based proteomics analysis, we identified 163 differentially expressed proteins (DEPs) between tail suspension and control samples, and among them, 128 proteins were upregulated and 35 proteins were downregulated. Functional and network analyses of the DEPs indicated that several of mitochondrial metabolic processes including the tricarboxylic acid (TCA) cycle were altered by simulating microgravity (SM). We verified 3 upregulated proteins, aconitate hydratase (ACO2), dihydrolipoamide S-succinyltransferase (DLST), and citrate synthase (CS), in the TCA cycle process by western blotting and confirmed their differential expressions between tail suspension and control samples. Taken together, our results demonstrate that 28-day tail suspension can cause changes in the morphology and metabolic function of hippocampus mitochondria, which might represent a mechanism of cognitive disorder caused by aerospace microgravity.


Assuntos
Proteômica , Ausência de Peso , Animais , Hipocampo/metabolismo , Mitocôndrias , Proteômica/métodos , Ratos , Ratos Sprague-Dawley , Ausência de Peso/efeitos adversos , Simulação de Ausência de Peso
17.
J Cardiovasc Transl Res ; 15(4): 805-815, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35088374

RESUMO

Microgravity conditions cause myocardial abnormalities with limited therapeutic approaches. We reported that NADPH oxidase-derived reactive oxygen species contribute to microgravity-induced myocardial abnormalities. This study investigated whether pharmacological inhibition of Rac1 protected the heart during microgravity. Simulated microgravity was induced by tail-suspension in mice. Tail-suspension for 28 days increased Rac1 activity in hearts, reduced heart weight and cross-sectional areas of cardiomyocytes, indicative of myocardial atrophy, and myocardial dysfunction. Administration of NSC23766, a selective inhibitor of Rac1, or atorvastatin reported to inhibit Rac1 activation, attenuated myocardial atrophy and preserved myocardial function in tail-suspended mice. These protective effects of Rac1 inhibition were associated with inhibition of NADPH oxidase activation and a reduction of oxidative stress. Our finding may inform a future clinical trial using atorvastatin to prevent myocardial abnormalities under microgravity conditions.


Assuntos
Cauda , Proteínas rac1 de Ligação ao GTP , Camundongos , Animais , Proteínas rac1 de Ligação ao GTP/metabolismo , Cauda/metabolismo , Atorvastatina/farmacologia , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Miócitos Cardíacos/metabolismo , Atrofia/patologia
18.
Front Oncol ; 12: 1021625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36620563

RESUMO

Background: Early gastric cancer (EGC) has a high survival rate, but it is difficult to diagnosis. Recently, artificial intelligence (AI) based on deep convolutional neural network (DCNN) has made significant progress in the field of gastroenterology. The purpose of this study was to establish a DCNN assist system to improve the detection of EGC. Methods: 3400 EGC and 8600 benign images were collected to train the DCNN to detect EGC. Subsequently, its diagnostic ability was compared to that of endoscopists using an independent internal test set (ITS, including 1289 images) and an external test set (ETS, including 542 images) come from three digestive center. Results: The diagnostic time of DCNN and endoscopists were 0.028s, 8.05 ± 0.21s, 7.69 ± 0.25s in ITS, and 0.028s, 7.98 ± 0.19s, 7.50 ± 0.23s in ETS, respectively. In ITS, the diagnostic sensitivity and accuracy of DCNN are 88.08%(95% confidence interval,95%CI,85.24%-90.44%), 88.60% (95%CI,86.74%-90.22%), respectively. In ETS, the diagnostic sensitivity and accuracy are 92.08% (95%CI, 87.91%- 94.94%),92.07%(95%CI, 89.46%-94.08%),respectively. DCNN outperformed all endoscopists in ETS, and had a significantly higher sensitivity than the junior endoscopists(JE)(by18.54% (95%CI, 15.64%-21.84%) in ITS, also higher than JE (by21.67%,95%CI, 16.90%-27.32%) and senior endoscopists (SE) (by2.08%, 95%CI, 0.75%-4.92%)in ETS. The accuracy of DCNN model was higher (by10.47%,95%CI, 8.91%-12.27%) than that of JE in ITS, and also higher (by14.58%,95%CI, 11.84%-17.81%; by 1.94%,95%CI,1.25%-2.96%, respectively) than JE and SE in ETS. Conclusion: The DCNN can detected more EGC images in a shorter time than the endoscopists. It will become an effective tool to assist in the detection of EGC in the near future.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34653004

RESUMO

Acupoint specificity for diseases has consistently been the focus of acupuncture research owing to its excellent prospects for clinical diagnosis and treatment. However, the specificity of cardiovascular and sleep functions in terms of electrical signals at acupoints remains unclear. In this study, five volunteers were recruited and their electrophysiological signals of GV20 (baihui), RN17 (danzhong), PC6 (neiguan), and SP6 (sanyinjiao) and the corresponding sham points, Pittsburgh sleep quality index, blood pressure, and echocardiography were monitored over four periods of 90-day head-down bed rest (HDBR). The results demonstrated that the power and characteristic amplitude of the acupoints were more significant than those of the sham points under normal conditions. And along with the altered physiological condition of the body after HDBR, the differential signal characteristic amplitude (DSCA) and the power of the acupoints were decreased to a larger extent than those of the sham points. In addition, the difference between the power of acupuncture and sham points was also reduced. During the recovery period, except for GV20, the power and DSCA of other acupoints did not return to normal. In terms of DSCA, GV20 is related to human sleep function and other acupoints are related to cardiovascular function. The above results show that the electrophysiological signals of acupoints are disease-specific and more accurately reflect the changes of physiological homeostasis. The research conduces to the development of acupuncture-based disease diagnosis and treatment integrated methods, and the realization of the portable and accurate diagnosis and regulation of diseases in space medicine.


Assuntos
Terapia por Acupuntura , Ausência de Peso , Pontos de Acupuntura , Fenômenos Eletrofisiológicos , Humanos , Sono
20.
Plant Sci ; 310: 110983, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34315599

RESUMO

The Arabidopsis thaliana R2R3-MYB transcription factor AtMYB32 and its homologs AtMYB4 and AtMYB7 play crucial roles in the regulation of phenylpropanoid metabolism. In addition, AtMYB4 and AtMYB7 are involved in the response to abiotic stress. However, the function of AtMYB32 remains unclear. In this study, we found that AtMYB32 is induced by abscisic acid (ABA) and repressed by drought stress. AtMYB32 positively regulates ABA-mediated seed germination and early seedling development. The expression of ABSCISIC ACID-INSENSITIVE 3 (ABI3), ABI4 and ABI5, which encode key positive regulators of ABA signaling, was upregulated in response to ABA in AtMYB32-overexpressing plants and downregulated in the atmyb32-1 mutant. In addition, we found that the atmyb32-1 mutant was drought resistant. Consistent with the drought-resistant phenotype, the transcript levels of C-repeat binding factor 4 (CBF4) were higher in the atmyb32-1 mutant in response to drought stress. Electrophoretic mobility shift assays (EMSAs) and chromatin immunoprecipitation (ChIP) assays revealed that AtMYB32 binds directly to the ABI3, ABI4, ABI5 and CBF4 promoters both in vitro and in vivo. Genetically, ABI4 was found to be epistatic to AtMYB32 for ABA-induced inhibition of seed germination and early seedling development. Taken together, our findings revealed that AtMYB32 regulates the ABA response by directly promoting ABI3, ABI4 and ABI5 expression and that the drought stress response likely occurs because of repression of CBF4 expression.


Assuntos
Ácido Abscísico/farmacologia , Proteínas de Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/efeitos dos fármacos , Secas , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Transativadores/efeitos dos fármacos , Fatores de Transcrição/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...