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Abdominal aortic aneurysm (AAA) is a life-threatening disease that remains undetected until it acutely ruptures. Due to lack of effective pharmaceutic therapies, it is urgent to explore new prevention and treatment strategies. Metabolic reprogramming is a cellular process through which cells change their metabolic patterns to meet material and energy requirements, including glucose metabolism, lipid metabolism and amino acid metabolism. Recently, the regulatory role of metabolic reprogramming in cardiovascular diseases, especially AAA, has attracted significant attention. This review article focuses on the research progress regarding the effects of metabolic reprogramming of vascular smooth muscle cells (VSMCs) and macrophages on the occurrence and development of AAA, especially their roles in major pathological processes such as VSMCs apoptosis and phenotype transformation, extracellular matrix remodeling, oxidative stress, and inflammatory response. The aim is to provide new clues for the mechanism research and clinical treatment of AAA from the perspective of metabolism.
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Aneurisma da Aorta Abdominal , Músculo Liso Vascular , Aneurisma da Aorta Abdominal/metabolismo , Humanos , Músculo Liso Vascular/metabolismo , Animais , Miócitos de Músculo Liso/metabolismo , Macrófagos/metabolismo , Estresse Oxidativo , Apoptose , Metabolismo dos Lipídeos , Reprogramação Celular , Reprogramação MetabólicaRESUMO
Postoperative acute kidney injury (AKI) is a common complication in patients undergoing deep hypothermic circulatory arrest (HCA); however, its underlying pathogenesis is unclear. In this study, we established a rat cardiopulmonary bypass model and demonstrated that hypothermia during HCA, rather than circulatory arrest, was responsible for the occurrence of AKI. By recruiting 56 patients who underwent surgery with HCA and analyzing the blood samples, we found that post-HCA AKI was associated with an increase in bradykinin. Animal experiments confirmed this and showed that hypothermia during HCA increased bradykinin levels by increasing kallikrein expression. Mechanistically, bradykinin inhibited the Nrf2-xCT pathway through B2R and caused renal oxidative stress damage. Application of Icatibant, a B2R inhibitor, reversed changes in the Nrf2-xCT pathway and oxidative stress damage. Finally, Icatibant reversed hypothermia-induced AKI in vivo. This finding reveals the pathogenesis of AKI after HCA and helps to provide therapeutic strategy for patients with post-HCA AKI.
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BACKGROUND: Ruminant gut microbiota are critical in ecological adaptation, evolution, and nutrition utilization because it regulates energy metabolism, promotes nutrient absorption, and improves immune function. To study the functional roles of key gut microbiota in sheep and goats, it is essential to construct reference microbial gene catalogs and high-quality microbial genomes database. RESULTS: A total of 320 fecal samples were collected from 21 different sheep and goat breeds, originating from 32 distinct farms. Metagenomic deep sequencing and binning assembly were utilized to construct a comprehensive microbial genome information database for the gut microbiota. We successfully generated the largest reference gene catalogs for gut microbiota in sheep and goats, containing over 162 million and 82 million nonredundant predicted genes, respectively, with 49 million shared nonredundant predicted genes and 1138 shared species. We found that the rearing environment has a greater impact on microbial composition and function than the host's species effect. Through subsequent assembly, we obtained 5810 medium- and high-quality metagenome-assembled genomes (MAGs), out of which 2661 were yet unidentified species. Among these MAGs, we identified 91 bacterial taxa that specifically colonize the sheep gut, which encode polysaccharide utilization loci for glycan and mucin degradation. CONCLUSIONS: By shedding light on the co-symbiotic microbial communities in the gut of small ruminants, our study significantly enhances the understanding of their nutrient degradation and disease susceptibility. Our findings emphasize the vast potential of untapped resources in functional bacterial species within ruminants, further expanding our knowledge of how the ruminant gut microbiota recognizes and processes glycan and mucins. Video Abstract.
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Bactérias , Fezes , Microbioma Gastrointestinal , Cabras , Mucinas , Polissacarídeos , Animais , Cabras/microbiologia , Ovinos/microbiologia , Mucinas/metabolismo , Polissacarídeos/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Fezes/microbiologia , Metagenoma , Genoma Bacteriano , Metagenômica/métodos , Filogenia , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
Background: Patients with obstructive sleep apnea hypopnea syndrome (OSAHS) combined with resistant hypertension (RH) have a high risk of developing primary aldosteronism (PA). This study investigated the aldosterone-renin ratio (ARR), plasma aldosterone concentration (PAC), and plasma renin activity (PRA) to determine the optimal cutoff values for PA diagnosis in patients with OSAHS combined with RH. Methods: Patients diagnosed with moderate and severe OSAHS combined with RH were recruited from the inpatient clinic of the Department of Endocrinology at Ji'an Central Hospital between October 2020 and April 2023. The included patients were divided into PA and no-PA groups. Diagnostic accuracy measures were calculated for each group, and receiver operating characteristic (ROC) curves were generated. Results: A total of 241 patients were included, of which 103 had positive ARR screening results in the diagnostic accuracy analysis and 66 were diagnosed with PA. PAC and ARR showed moderate predictive capacity for PA, with area under the curve (AUC) values of 0.66 [95% confidence interval (CI): 0.55-0.77] and 0.72 (95% CI: 0.63-0.82), respectively, while PRA exhibited a limited predictive capacity (AUC = 0.51, 95% CI: 0.40-0.63). Using 45 as the optimal cutoff value for ARR, the sensitivity was 86% and the specificity was 52%. The optimal cutoff value for PAC was 17, with a sensitivity of 78% and a specificity of 55%. Notably, in patients with severe OSAHS, ARR at screening demonstrated significant predictive value for PA, with an AUC of 0.84 (95% CI: 0.72-0.96), a sensitivity of 85%, and a specificity of 76%. Conversely, in patients with moderate OSAHS, only ARR demonstrated significant predictive value for PA diagnosis, while PAC did not demonstrate notable diagnostic value. Conclusion: ARR and PAC are initial screening tools for PA, facilitating early detection, particularly in low-resource settings. In patients with OSAHS and RH, the ARR and PAC thresholds for PA diagnosis may require more stringent adjustment.
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The behavior of pigs is intricately tied to their health status, highlighting the critical importance of accurately recognizing pig behavior, particularly abnormal behavior, for effective health monitoring and management. This study addresses the challenge of accommodating frequent non-rigid deformations in pig behavior using deformable convolutional networks (DCN) to extract more comprehensive features by incorporating offsets during training. To overcome the inherent limitations of traditional DCN offset weight calculations, the study introduces the multi-path coordinate attention (MPCA) mechanism to enhance the optimization of the DCN offset weight calculation within the designed DCN-MPCA module, further integrated into the cross-scale cross-feature (C2f) module of the backbone network. This optimized C2f-DM module significantly enhances feature extraction capabilities. Additionally, a gather-and-distribute (GD) mechanism is employed in the neck to improve non-adjacent layer feature fusion in the YOLOv8 network. Consequently, the novel DM-GD-YOLO model proposed in this study is evaluated on a self-built dataset comprising 11,999 images obtained from an online monitoring platform focusing on pigs aged between 70 and 150 days. The results show that DM-GD-YOLO can simultaneously recognize four common behaviors and three abnormal behaviors, achieving a precision of 88.2%, recall of 92.2%, and mean average precision (mAP) of 95.3% with 6.0MB Parameters and 10.0G FLOPs. Overall, the model outperforms popular models such as Faster R-CNN, EfficientDet, YOLOv7, and YOLOv8 in monitoring pens with about 30 pigs, providing technical support for the intelligent management and welfare-focused breeding of pigs while advancing the transformation and modernization of the pig industry.
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The expression of large conductance calcium-activated potassium channels (BK channels) in adipose tissue has been identified for years. BK channel deletion can improve metabolism in vivo, but the relative mechanisms remain unclear. Here, we examined the effects of BK channels on the differentiation of adipose-derived stem cells (ADSCs) and the related mechanisms. BKα and ß1 subunits were expressed on adipocytes. We found that both deletion of the KCNMA1 gene, encoding the pore forming α subunit of BK channels, and the BK channel inhibitor paxilline increased the expression of key genes in the peroxisome proliferator activated receptor (PPAR) pathway and promoted adipogenetic differentiation of ADSCs. We also observed that the MAPK-ERK pathway participates in BK channel deficiency-promoted adipogenic differentiation of ADSCs and that ERK inhibitors blocked the differentiation-promoting effect of BK channel deficiency. Hyperplasia of adipocytes is considered beneficial for metabolic health. These results indicate that BK channels play an important role in adipose hyperplasia by regulating the differentiation of ADSCs and may become an important target for studying the pathogenesis and treatment strategies of metabolic disorder-related diseases.
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Canais de Potássio Ativados por Cálcio de Condutância Alta , Sistema de Sinalização das MAP Quinases , Humanos , Canais de Potássio Ativados por Cálcio de Condutância Alta/genética , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Hiperplasia , Diferenciação Celular , Adipócitos/metabolismoRESUMO
Phenotypic transition of vascular smooth muscle cells (VSMCs) is an early event in the onset and progression of several cardiovascular diseases. As an important mediator of the renin-angiotensin system (RAS), activation of the angiotensin II type 1 receptor (AT1R) induces phenotypic transition of VSMCs. AT1R autoantibodies (AT1-AAs), which are agonistic autoantibodies of AT1R, have been detected in the sera of patients with a variety of cardiovascular diseases associated with phenotypic transition. However, the effect of AT1-AA on phenotypic transition is currently unknown. In this study, AT1-AA-positive rat model was established by active immunization to detect markers of VSMCs phenotypic transition. The results showed that AT1-AA-positive rats showed phenotypic transition of VSMCs, which was evidenced by the decrease of contractile markers, while the increase of synthetic markers in the thoracic aorta. However, in AT1-AA-positive AT1R knockout rats, the phenotypic transition-related proteins were not altered. In vitro, after stimulating human aortic smooth muscle cells with AT1-AA for 48 h, 2'-5' oligoadenylate synthase 2 (OAS2) was identified as the key differentially expressed gene by RNA sequencing and bioinformatics analysis. Furthermore, high expression of OAS2 was found in aorta of AT1-AA-positive rats; knockdown of OAS2 by siRNA can reverse the phenotypic transition of VSMCs induced by AT1-AA. In summary, this study suggests that AT1-AA can promote phenotypic transition of VSMCs through AT1R-OAS2 pathway, and OAS2 might serve as a potential therapeutic target to prevent pathological phenotypic transition of smooth muscle cells.
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2',5'-Oligoadenilato Sintetase , Autoanticorpos , Doenças Cardiovasculares , Receptor Tipo 1 de Angiotensina , Animais , Humanos , Ratos , Autoanticorpos/metabolismo , Miócitos de Músculo Liso/metabolismo , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , 2',5'-Oligoadenilato Sintetase/genética , 2',5'-Oligoadenilato Sintetase/metabolismoRESUMO
Angiotensin II type 1 receptor (AT1R) is a promising therapeutic target for cardiovascular diseases. Compared with orthosteric ligands, allosteric modulators attract considerable attention for drug development due to their unique advantages of high selectivity and safety. However, no allosteric modulators of AT1R have been applied in clinical trials up to now. Except for the classical allosteric modulators of AT1R such as antibody, peptides and amino acids, cholesterol and biased allosteric modulators, there are non-classical allosteric modes including the ligand-independent allosteric mode, and allosteric mode of biased agonists and dimers. In addition, finding the allosteric pockets based on AT1R conformational change and interaction interface of dimers are the future of drug design. In this review, we summarize the different allosteric mode of AT1R, with a view to contribute to the development and utilization of drugs targeting AT1R allostery.
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A Te-doped CoTe2 film could be grown in situ on reduced graphene oxide (rGO) to develop a Te-CoTe2/rGO composite with an ultrathin layered structure, which has multiple protective effects on both the sulfur positive electrode and lithium negative electrode in lithium sulfur (Li-S) batteries. The Te-CoTe2/rGO composite as a sulfur host not only shows a strong adsorbing ability for lithium polysulfides (LiPSs) but can also accelerate the conversion reaction of active material sulfur during the charging/discharging process. More importantly, this host can turn the shuttle effect from an unfavorable factor to a favorable factor, which could improve the electrochemical performance of the lithium anode with uniform lithium plating/stripping resulting from the intermediate polytellurosulfide species (Li2TexSy), which could be generated on the cathode surface via Te reacting with soluble Li2Sn (4 ≤ n ≤ 8). As a result, the S@Te-CoTe2/rGO cathode shows a discharge capacity of 970.0 mA h g-1 in the first cycle at 1 C and retains a high capacity of 545.5 mA h g-1 after 1000 cycles, corresponding to a low capacity decay rate of only 0.043% per cycle. In addition, in situ X-ray diffraction (XRD) and in situ Raman were used to explore the sulfur conversion process. This study not only demonstrates that a two-dimensional (2D) ultrathin Te-CoTe2/rGO composite is successfully developed with multiple effects on Li-S batteries but also opens a new pathway for designing unique sulfur hosts to promote the electrochemical performance of Li-S batteries.
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The chromatin loops in the three-dimensional (3D) structure of chromosomes are essential for the regulation of gene expression. Despite the fact that high-throughput chromatin capture techniques can identify the 3D structure of chromosomes, chromatin loop detection utilizing biological experiments is arduous and time-consuming. Therefore, a computational method is required to detect chromatin loops. Deep neural networks can form complex representations of Hi-C data and provide the possibility of processing biological datasets. Therefore, we propose a bagging ensemble one-dimensional convolutional neural network (Be-1DCNN) to detect chromatin loops from genome-wide Hi-C maps. First, to obtain accurate and reliable chromatin loops in genome-wide contact maps, the bagging ensemble learning method is utilized to synthesize the prediction results of multiple 1DCNN models. Second, each 1DCNN model consists of three 1D convolutional layers for extracting high-dimensional features from input samples and one dense layer for producing the prediction results. Finally, the prediction results of Be-1DCNN are compared to those of the existing models. The experimental results indicate that Be-1DCNN predicts high-quality chromatin loops and outperforms the state-of-the-art methods using the same evaluation metrics. The source code of Be-1DCNN is available for free at https://github.com/HaoWuLab-Bioinformatics/Be1DCNN.
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Cromatina , Cromossomos , Mapeamento Cromossômico , Redes Neurais de Computação , Aprendizado de MáquinaRESUMO
BACKGROUND: Acute type A aortic dissection (ATAAD) is a life-threatening pathological change of the aorta. Patients who have undergone aortic surgery are usually at high risk of mortality. AIM: We investigated the predictive value of serum Mammalian sterile 20-like kinase 1 (MST1) as a biomarker for the risk of mortality of ATAAD patients. METHODS: In this retrospective cohort study, we analyzed 160 consecutive ATAAD patients who had undergone emergency surgery from July 2016 to April 2017. Medical records and blood samples were collected and analyzed. ELISA assays were performed to detect the concentrations of several proteins including MST1. The relationship between these potential biomarkers and the primary endpoint of death was evaluated using Cox proportional hazard regression analysis. RESULTS: Compared with a low level (< 1330.8 ng/L), high serum MST1 level (≥ 1330.8 ng/L) was positively associated with the 30-day mortality (OR = 5.233, 95%CI, 1.843-14.862, P < 0.01) and retained predictive after adjustment for sex, age, BMI, nasopharyngeal temperature and deep hypothermia circulatory arrest time (OR = 4.628 95% CI, 1.572-13.625, P < 0.01). A pre-existing basic clinical prediction model was improved with the inclusion of preoperative serum MST1. Specifically, the area under the ROC curve for base model (history of cerebrovascular disease, creatinine, time of operation) was 0.708 (95%CI, 0.546-0.836) and markedly increased to 0.823 when taking MST1 into consideration (95%CI, 0.700-0.912, P = 0.02). CONCLUSION: Our study suggests that high preoperative circulating MST1, with a concentration greater than 1330.8 ng/L, was correlated with the 30-day mortality of ATAAD patients who underwent emergency surgery.
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Dissecção Aórtica , Modelos Estatísticos , Humanos , Estudos Retrospectivos , Prognóstico , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Biomarcadores , Resultado do TratamentoRESUMO
Sheep detection and segmentation will play a crucial role in promoting the implementation of precision livestock farming in the future. In sheep farms, the characteristics of sheep that have the tendency to congregate and irregular contours cause difficulties for computer vision tasks, such as individual identification, behavior recognition, and weight estimation of sheep. Sheep instance segmentation is one of the methods that can mitigate the difficulties associated with locating and extracting different individuals from the same category. To improve the accuracy of extracting individual sheep locations and contours in the case of multiple sheep overlap, this paper proposed two-stage sheep instance segmentation SheepInst based on the Mask R-CNN framework, more specifically, RefineMask. Firstly, an improved backbone network ConvNeXt-E was proposed to extract sheep features. Secondly, we improved the structure of the two-stage object detector Dynamic R-CNN to precisely locate highly overlapping sheep. Finally, we enhanced the segmentation network of RefineMask by adding spatial attention modules to accurately segment irregular contours of sheep. SheepInst achieves 89.1%, 91.3%, and 79.5% in box AP, mask AP, and boundary AP metric on the test set, respectively. The extensive experiments show that SheepInst is more suitable for sheep instance segmentation and has excellent performance.
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The sluggish redox kinetics and the severe shuttle effect of soluble lithium polysulfides (LiPSs) are the main key issues which would hinder the development of lithium-sulfur (Li-S) batteries. In this work, a nickel-doped vanadium selenide in-situ grows on reduced graphene oxide(rGO) to form a two-dimensional (2D) composite Ni-VSe2/rGO by a simple solvothermal method. When it is used as a modified separator in Li-S batteries, the Ni-VSe2/rGO material with the doped defect and super-thin layered structure can greatly adsorb LiPSs and catalyze the conversion reaction of LiPSs, resulting in effectively reducing LiPSs diffusion and suppressing the shuttle effect. More importantly, the cathode-separator bonding body is first developed as a new strategy of electrode-separator integration in Li-S batteries, which not only could decrease the LiPSs dissolution and improve the catalysis performance of the functional separator as the upper current-collector, but also is good for the high sulfur loading and the low electrolyte/sulfur (E/S) ratio for high energy density Li-S batteries. When the Ni-VSe2/rGO-PP (polypropylene, Celgard 2400) modified separator is applied, the Li-S cell can retain 510.3 mA h g-1 capacity after 1190 cycles at 0.5C. In the electrode-separator integrated system, the Li-S cell can still maintain 552.9 mA h g-1 for 190 cycles at a sulfur loading 6.4 mg cm-2 and 4.9 mA h cm-2 for 100 cycles at a sulfur loading 7.0 mg cm-2. The experimental results indicate that both the doped defect engineering and the super-thin layered structure design might optimally be chosen to fabricate a new modified separator material, and especially, the electrode-separator integration strategy would open a practical way to promote the electrochemical behavior of Li-S batteries with high sulfur loading and low E/S ratio.
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OBJECTIVE: To study the feasibility, safety, and effectiveness of lateral thoracic adipofascial flaps in reconstructing the defects following breast-conserving surgery (BCS) in breasts with either no ptosis or mild ptosis. METHODS: 37 female patients who underwent BCS and lateral thoracic adipofascial flap breast reconstruction between June 2020 and July 2022 were analysed. Surgery-related complications, intraoperative positive margin, local recurrence, and cosmetic outcome were assessed. RESULTS: Three local complications occurred in patients, all of which were cured by conservative treatment. Additionally, four patients had intraoperative positive margins. After a median follow-up period of 17.5 months, none of the patients showed local recurrence. All patients achieved a satisfactory breast shape. Further, patients without ptosis achieved good volume and symmetry. However, the breast symmetry was not satisfactory for patients with ptosis. CONCLUSION: It is reliable and effective to use the lateral thoracic adipofascial flaps to reconstruct the defects after BCS when the breast is not ptotic and the lesions are located in the lateral and central quadrants.
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Neoplasias da Mama , Mamoplastia , Feminino , Humanos , Mastectomia Segmentar , Mama/patologia , Retalhos Cirúrgicos , Mamoplastia/efeitos adversos , Neoplasias da Mama/cirurgia , Resultado do TratamentoRESUMO
Single-cell clustering is the most significant part of single-cell RNA sequencing (scRNA-seq) data analysis. One main issue facing the scRNA-seq data is noise and sparsity, which poses a great challenge for the advance of high-precision clustering algorithms. This study adopts cellular markers to identify differences between cells, which contributes to feature extraction of single cells. In this work, we propose a high-precision single-cell clustering algorithm-SCMcluster (single-cell cluster using marker genes). This algorithm integrates two cell marker databases(CellMarker database and PanglaoDB database) with scRNA-seq data for feature extraction and constructs an ensemble clustering model based on the consensus matrix. We test the efficiency of this algorithm and compare it with other eight popular clustering algorithms on two scRNA-seq datasets derived from human and mouse tissues, respectively. The experimental results show that SCMcluster outperforms the existing methods in both feature extraction and clustering performance. The source code of SCMcluster is available for free at https://github.com/HaoWuLab-Bioinformatics/SCMcluster.
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Perfilação da Expressão Gênica , Análise de Célula Única , Animais , Humanos , Camundongos , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Algoritmos , Análise por ConglomeradosRESUMO
The study of the vibration phenomenon of pebbles under turbulence is still a gap despite recent technological advancements in measurement capabilities. In this study, the vibration process of a fully exposed, isolated smart pebble on a rough bed was measured using a miniature inertial accelerometer and combined with simultaneous local measurements of the near-bed velocities. The paper conducts a series of experimental studies with different flow conditions. The test data match well with the manually observed phenomena, indicating the authenticity of the sediment vibration data collected by the measurement system. The test results show that the pebble motion (before entrainment) subjected to turbulence is a nonlinear vibration process, and its vibration types include in-situ vibration and ex-situ strong vibration. The probability distribution for the amplitude of vibration acceleration is well parameterized by the normal distribution. The vibration intensity tends to increase before approaching the threshold, but it weakens when approaching the point. The sediment vibration frequency is within 20-25 Hz, similar to the flow pulsation frequency and belongs to low-frequency vibration. The data indicate that the near-bed flow velocity is most directly related to the particle vibration events.
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Aceleração , Vibração , Movimento (Física) , AcelerometriaRESUMO
The activation and proliferation of hepatic stellate cells (HSCs) are critical processes for the treatment of liver fibrosis. It is necessary to identify effective drugs for the treatment of liver fibrosis and elucidate their mechanisms of action. Metformin can inhibit HSCs; however, no systematic studies demonstrating the effects of metformin on mitochondria in HSCs have been reported. This study demonstrated that metformin induces mitochondrial fission by phosphorylating AMPK/DRP1 (S616) in HSCs to decrease the expression of α-SMA and collagen. Additionally, metformin repressed the total ATP production rate, especially the production rate of ATP produced through mitochondrial oxidative phosphorylation, by inhibiting the enzymatic activity of complex I. Further analysis revealed that metformin strongly constrained the transcription of mitochondrial genes (ND1-ND6 and ND4L) that encode the core subunits of respiratory chain I. Upregulation of the mRNA expression of HK2 and GLUT1 slightly enhanced glycolysis. Additionally, metformin increased mitochondrial DNA (mtDNA) copy number to suppress the proliferation and activation of HSCs, indicating that mtDNA copy number can alter the fate of HSCs. In conclusion, metformin can induce mitochondrial fragmentation and low-level energy metabolism in HSCs, thereby suppressing HSCs activation and proliferation to reverse liver fibrosis.
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Metformina , Humanos , Metformina/farmacologia , Fígado/metabolismo , Células Estreladas do Fígado/metabolismo , Dinâmica Mitocondrial , Transporte de Elétrons , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Metabolismo Energético , DNA Mitocondrial/metabolismo , Trifosfato de Adenosina/metabolismoRESUMO
Baroreceptors are nerve endings located in the adventitia of the carotid sinus and aortic arch. They act as a mechanoelectrical transducer that can sense the tension stimulation exerted on the blood vessel wall by the rise in blood pressure and transduce the mechanical force into discharge of the nerve endings. However, the molecular identity of mechanical signal transduction from the vessel wall to the baroreceptor is not clear. We discovered that exogenous integrin ligands, such as RGD, IKVAV, YIGSR, PHSRN, and KNEED, could restrain pressure-dependent discharge of the aortic nerve in a dose-dependent and reversible manner. Perfusion of RGD at the baroreceptor site in vivo can block the baroreceptor reflex. An immunohistochemistry study showed the binding of exogenous RGD to the nerve endings under the adventitia of the rat aortic arch, which may competitively block the binding of integrins to ligand motifs in extracellular matrix. These findings suggest that connection of integrins with extracellular matrix plays an important role in the mechanical coupling process between vessel walls and arterial baroreceptors.
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Mecanotransdução Celular , Pressorreceptores , Ratos , Animais , Pressorreceptores/fisiologia , Aorta/inervação , ArtériasRESUMO
Juxtaglomerular cell tumor (JCT) is an endocrine tumor marked by elevated renin levels and high blood pressure. This case report presents the clinical findings of a 47-year-old woman with a history of recurrent hypokalemia, headaches, hypertension, and increased plasma renin activity (PRA). Dynamic enhanced magnetic resonance imaging (MRI) revealed a small nodule on the upper part of the right kidney. Selective renal venous sampling indicated a higher PRA only in the right upper pole renal vein. The patient underwent surgical removal of the right kidney mass, and the pathology results confirmed the diagnosis of JCT. This case underscores the importance of conducting selective renal venous sampling for accurate JCT diagnosis.
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Background: Vascular smooth muscle cells (VSMCs) phenotype switching is very important during the pathogenesis and progression of vascular diseases. However, it is not well understood how normal VSMCs maintain the differentiated state. The large-conductance Ca2+-activated K+ (BKCa) channels are widely expressed in VSMCs and regulate vascular tone. Nevertheless, there is limited understanding of the role of the BKCa channel in modulation of the VSMC phenotype. Methods and results: We assessed BKCa channel expression levels in normal and injured carotid arteries from rats of the balloon-injury model. A strong decrease of BKCa-ß1 was seen in the injured carotid arteries, accompanied by a parallel decrease of the VSMC contractile markers. BKCa-ß1 in primary rat aortic VSMCs was decreased with the increase of passage numbers and the stimulation of platelet-derived growth factor (PDGF)-BB. Conversely, transforming growth factor ß upregulated BKCa-ß1. Meanwhile, the BKCa-ß1 level was positively associated with the levels of VSMC contractile proteins. Intravenous injection of PDGF-BB induced downregulation of BKCa-ß1 expression in the carotid arteries. Knockdown of BKCa-ß1 favored VSMC dedifferentiation, characterized by altered morphology, abnormal actin fiber organization, decreased contractile proteins expression and reduced contractile ability. Furthermore, the resultant VSMC dedifferentiated phenotype rendered increased proliferation, migration, enhanced inflammatory factors levels, and matrix metalloproteinases activity. Studies using primary cultured aortic VSMCs from human recapitulated key findings. Finally, protein level of BKCa-ß1 was reduced in human atherosclerotic arteries. Conclusion: BKCa-ß1 is important in the maintenance of the contractile phenotype of VSMCs. As a novel endogenous defender that prevents pathological VSMC phenotype switching, BKCa-ß1 may serve as a potential therapeutic target for treating vascular diseases including post-injury restenosis and atherosclerosis.