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Small and medium-sized enterprises (SMEs) were an important part of China's economy, but they faced challenges to growth due to financing difficulties. Government subsidies are considered as a potential way to address this problem. This study aims to assess the effectiveness of the Chinese government's subsidy program aimed at improving the accessibility of financing for SMEs. We analyze a comprehensive dataset of Chinese firms' subsidy programs from 2011 to 2020. We classify subsidies into unconditional and conditional categories and use fixed-effects regression models to control for the effects of time and between-group variation to more accurately assess the effectiveness of government subsidies. In addition, we use a PSM-DID model to reduce the effect of selectivity bias to more accurately estimate the causal effect of subsidies on financing strategies. We also use a mediated effects model to help understand the mechanisms by which different types of subsidies affect financing strategies. The results show that government subsidies can significantly improve SMEs' financing ability, but different types of subsidies produce subtle differences. Conditional subsidies support debt financing mainly through incentives, while unconditional subsidies help SMEs improve their equity financing ability through information effects. Furthermore, we find that over-reliance on a single subsidy type may reduce its effectiveness, suggesting a complex relationship between government intervention and SME financing. Thus, well-designed policies are crucial for promoting SMEs and fostering economic growth.
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Financiamento Governamental , China , Humanos , Modelos EconômicosRESUMO
Background: While observational studies have demonstrated connections between cigarette smoking, alcohol consumption, and arterial stiffness, establishing a causal relationship has proven challenging because of potential confounding factors. To address this problem, we employed a two-sample Mendelian randomization approach. Methods: We selected genetic instruments for these risk factors from genome-wide association studies encompassing 3,383,199 individuals at the genome-wide significance level (p < 5 × 10 - 9 ). Arterial stiffness data were acquired from the UK Biobank, which included 127,121 participants. Our primary analysis utilized the inverse variance-weighted method to explore causality. To confirm our results' robustness, we conducted sensitivity analyses using Egger regression, the weighted median method, and Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO). Results: Our analysis revealed a significant association between genetic inclination to smoking initiation and an increase in the arterial stiffness index ( ß = 0.11; 95% confidence interval [CI], 0.06 to 0.16; p = 1.95 × 10 - 5 ). Additionally, there was a suggestive connection between genetically predicted number of cigarettes per day and the arterial stiffness index ( ß = 0.05; 95% CI, 5.25 × 10 - 4 to 0.10; p = 4.75 × 10 - 2 ). No causal relationships were observed between the genetically predicted age of smoking initiation, smoking cessation, or alcohol consumption and the risk of arterial stiffness index. Conclusions: This Mendelian randomization study indicates that smoking initiation is likely a causative risk factor for arterial stiffness. However, further research is needed to determine if the quantity of daily cigarettes directly contributes to arterial stiffness development. Regarding alcohol consumption, age of smoking initiation, and smoking cessation, there was insufficient evidence to establish causality.
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Due to the increasing severity of aging populations in modern society, the accurate and timely identification of, and responses to, sudden abnormal behaviors of the elderly have become an urgent and important issue. In the current research on computer vision-based abnormal behavior recognition, most algorithms have shown poor generalization and recognition abilities in practical applications, as well as issues with recognizing single actions. To address these problems, an MSCS-DenseNet-LSTM model based on a multi-scale attention mechanism is proposed. This model integrates the MSCS (Multi-Scale Convolutional Structure) module into the initial convolutional layer of the DenseNet model to form a multi-scale convolution structure. It introduces the improved Inception X module into the Dense Block to form an Inception Dense structure, and gradually performs feature fusion through each Dense Block module. The CBAM attention mechanism module is added to the dual-layer LSTM to enhance the model's generalization ability while ensuring the accurate recognition of abnormal actions. Furthermore, to address the issue of single-action abnormal behavior datasets, the RGB image dataset RIDS (RGB image dataset) and the contour image dataset CIDS (contour image dataset) containing various abnormal behaviors were constructed. The experimental results validate that the proposed MSCS-DenseNet-LSTM model achieved an accuracy, sensitivity, and specificity of 98.80%, 98.75%, and 98.82% on the two datasets, and 98.30%, 98.28%, and 98.38%, respectively.
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Algoritmos , Redes Neurais de Computação , Humanos , Reconhecimento Automatizado de Padrão/métodos , Comportamento/fisiologia , Processamento de Imagem Assistida por Computador/métodosRESUMO
Naturally occurring lanthipeptides, peptides post-translationally modified by various enzymes, hold significant promise as antibiotics. Despite extensive biochemical and structural studies, the events preceding peptide modification remain poorly understood. Here, we identify a distinct subclass of lanthionine synthetase KC (LanKC) enzymes with distinct structural and functional characteristics. We show that PneKC, a member of this subclass, forms a dimer and possesses GTPase activity. Through three cryo-EM structures of PneKC, we illustrate different stages of peptide PneA binding, from initial recognition to full binding. Our structures show the kinase domain complexed with the PneA core peptide and GTPγS, a phosphate-bound lyase domain, and an unconventional cyclase domain. The leader peptide of PneA interact with a gate loop, transitioning from an extended to a helical conformation. We identify a dimerization hot spot and propose a "negative cooperativity" mechanism toggling the enzyme between tense and relaxed conformation. Additionally, we identify an important salt bridge in the cyclase domain, differing from those in in conventional cyclase domains. These residues are highly conserved in the LanKC subclass and are part of two signature motifs. These results unveil potential differences in lanthipeptide modification enzymes assembly and deepen our understanding of allostery in these multifunctional enzymes.
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Multimerização Proteica , Microscopia Crioeletrônica , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Peptídeos/química , Peptídeos/metabolismo , Modelos Moleculares , Alanina/química , Alanina/metabolismo , Alanina/análogos & derivados , Domínios Proteicos , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/química , Processamento de Proteína Pós-Traducional , Ligação Proteica , Ligases/metabolismo , Ligases/química , SulfetosRESUMO
Background: The toxin-antitoxin (TA) system plays a vital role in the virulence and pathogenicity of Mycobacterium tuberculosis (M. tuberculosis). However, the regulatory mechanisms and the impact of gene mutations on M. tuberculosis transmission remain poorly understood. Objective: To investigate the influence of gene mutations in the toxin-antitoxin system on M. tuberculosis transmission dynamics. Method: We performed whole-genome sequencing on the analyzed strains of M. tuberculosis. The genes associated with the toxin-antitoxin system were obtained from the National Center for Biotechnology Information (NCBI) Gene database. Mutations correlating with enhanced transmission within the genes were identified by using random forest, gradient boosting decision tree, and generalized linear mixed models. Results: A total of 13,518 M. tuberculosis isolates were analyzed, with 42.29% (n = 5,717) found to be part of genomic clusters. Lineage 4 accounted for the majority of isolates (n = 6488, 48%), followed by lineage 2 (n = 5133, 37.97%). 23 single nucleotide polymorphisms (SNPs) showed a positive correlation with clustering, including vapB1 G34A, vapB24 A76C, vapB2 T171C, mazF2 C85T, mazE2 G104A, vapB31 T112C, relB T226A, vapB11 C54T, mazE5 T344C, vapB14 A29G, parE1 (C103T, C88T), and parD1 C134T. Six SNPs, including vapB6 A29C, vapB31 T112C, parD1 C134T, vapB37 G205C, Rv2653c A80C, and vapB22 C167T, were associated with transmission clades across different countries. Notably, our findings highlighted the positive association of vapB6 A29C, vapB31 T112C, parD1 C134T, vapB37 G205C, vapB19 C188T, and Rv2653c A80C with transmission clades across diverse regions. Furthermore, our analysis identified 32 SNPs that exhibited significant associations with clade size. Conclusion: Our study presents potential associations between mutations in genes related to the toxin-antitoxin system and the transmission dynamics of M. tuberculosis. However, it is important to acknowledge the presence of confounding factors and limitations in our study. Further research is required to establish causation and assess the functional significance of these mutations. These findings provide a foundation for future investigations and the formulation of strategies aimed at controlling TB transmission.
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BACKGROUND: The volume measurement of intracerebral hemorrhage (ICH) and intraventricular hemorrhage (IVH) provides critical information for precise treatment of patients with spontaneous ICH but remains a big challenge, especially for IVH segmentation. However, the previously proposed ICH and IVH segmentation tools lack external validation and segmentation quality assessment. PURPOSE: This study aimed to develop a robust deep learning model for the segmentation of ICH and IVH with external validation, and to provide quality assessment for IVH segmentation. METHODS: In this study, a Residual Encoding Unet (REUnet) for the segmentation of ICH and IVH was developed using a dataset composed of 977 CT images (all contained ICH, and 338 contained IVH; a five-fold cross-validation procedure was adopted for training and internal validation), and externally tested using an independent dataset consisting of 375 CT images (all contained ICH, and 105 contained IVH). The performance of REUnet was compared with six other advanced deep learning models. Subsequently, three approaches, including Prototype Segmentation (ProtoSeg), Test Time Dropout (TTD), and Test Time Augmentation (TTA), were employed to derive segmentation quality scores in the absence of ground truth to provide a way to assess the segmentation quality in real practice. RESULTS: For ICH segmentation, the median (lower-quantile-upper quantile) of Dice scores obtained from REUnet were 0.932 (0.898-0.953) for internal validation and 0.888 (0.859-0.916) for external test, both of which were better than those of other models while comparable to that of nnUnet3D in external test. For IVH segmentation, the Dice scores obtained from REUnet were 0.826 (0.757-0.868) for internal validation and 0.777 (0.693-0.827) for external tests, which were better than those of all other models. The concordance correlation coefficients between the volumes estimated from the REUnet-generated segmentations and those from the manual segmentations for both ICH and IVH ranged from 0.944 to 0.987. For IVH segmentation quality assessment, the segmentation quality score derived from ProtoSeg was correlated with the Dice Score (Spearman r = 0.752 for the external test) and performed better than those from TTD (Spearman r = 0.718) and TTA (Spearman r = 0.260) in the external test. By setting a threshold to the segmentation quality score, we were able to identify low-quality IVH segmentation results by ProtoSeg. CONCLUSIONS: The proposed REUnet offers a promising tool for accurate and automated segmentation of ICH and IVH, and for effective IVH segmentation quality assessment, and thus exhibits the potential to facilitate therapeutic decision-making for patients with spontaneous ICH in clinical practice.
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Non-activated linear α-olefins are valuable building blocks for organic transformation or olefin (co)polymerization, but they are recognized as textbook knowledge for non-homopolymerizable monomers under radical conditions. In this article, we disclose our effort to achieve an unprecedented library of all carbon-bonded sequence-regulated polymers via radical isomerization homopolymerization of α-olefin derivatives. The success of this distinctive polymerization is attributed to the remarkable efficiency and selectivity exhibited during the cyano group migration or hydrogen atom transfer, which is greatly enhanced by the precise engineering of their monomer structures. This polymerization process enables the elongation of polymer chains by five, six, or seven carbon atoms at each propagation step. These polymers, obtained through the cyano group migration or hydrogen atom transfer involved radical isomerization polymerization processes, emerge as promising candidates resembling polyethylene or polyacrylonitrile copolymers.
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Electrooxidation of biomass-derived glycerol which is regarded as a main byproduct of industrial biodiesel production, is an innovative strategy to produce value-added chemicals, but currently showcases slow kinetics, limited Faraday efficiency, and unclear catalytic mechanism. Herein, we report high-efficiency electrooxidation of glycerol into formate via a Cu doped NiCo alloy catalyst supported on nickel foam (Cu-NiCo/NF) in a coupled system paired with nitrate reduction. The designed Cu-NiCo/NF delivers only 1.23 V vs. RHE at 10 mA cm-2, and a record Faraday efficiency of formate of 93.8%. The superior performance is ascribed to the rapid generation of NiIII-OOH and CoIII-OOH and favorable coupling of surface *O with reactive intermediates. Using Cu-NiCo/NF as a bifunctional catalyst, the coupled system synchronously produces NH3 and formate, showing 290 mV lower than the coupling of hydrogen evolution reaction, together with excellent long-term stability for up to 144 h. This work lays out new guidelines and reliable strategies from catalyst design to system coupling for biomass-derived electrochemical refinery.
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Sulfamoyl fluorides, as a crucial building block of SuFEx, have garnered extensive research interest due to their unique properties. However, the direct radical fluorosulfonamidation process for the synthesis of sulfamoyl fluorides has been overlooked. We herein disclosed a practical procedure for constructing a redox-active fluorosulfonamide radical reagent named fluorosulfonyl-N-pyridinium tetrafluoroborate (PNSF) from SO2F2. These reagents can facilitate a range of reactions, including the N-(fluorosulfonyl) sulfonamidation of (hetero)arenes, sequential radical stereoselective fluorosulfonamidation, and 1,2-difunctionalization of alkenes.
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OBJECTIVE: To analyze the association between the triglyceride-glucose (TyG) index and the risk of nephrolithiasis across various demographic and clinical subgroups, aiming to enhance early diagnosis and treatment of nephrolithiasis and promote personalized care in diverse populations. METHODS: This cross-sectional study analyzed the medical records of 84 968 adults, stratified into three categories (low, middle, high) according to their TyG index scores. To evaluate the association between the TyG index and nephrolithiasis risk, multivariable Logistic regression models were employed, adjusting for potential confounders. Additionally, piecewise linear regression models were used to investigate the non-linear dynamics of the TyG index's relationship with nephrolithiasis risk. Subgroup analyses were performed to explore variations in the effects of the TyG index across different demographic and clinical populations. RESULTS: Increasing TyG index was associated with a higher risk of nephrolithiasis, rising from 4.36% in the low group to 8.96% in the high group (P < 0.001). In adjusted models, males in the middle and high TyG index categories demonstrated significantly elevated risks of nephrolithiasis, with odds ratios of 1.18 (95%CI: 1.07-1.31, P=0.002) and 1.29 (95%CI: 1.15-1.45, P < 0.001), respectively. Conversely, in females, the association was not statistically significant post-adjustment (OR=0.98, 95%CI: 0.82-1.16, P=0.778). Among males, for each unit increment in the TyG index below the critical threshold of 8.98, there was a notable 40% escalation in the risk of developing nephrolithiasis (OR=1.40, 95%CI: 1.24-1.58, P < 0.001). Surpassing this threshold, the TyG index no longer conferred a significant increase in risk (OR=0.91, 95%CI: 0.78-1.06, P=0.24). Subgroup analyses indicated that this association remained stable regardless of age, BMI, or hypertension status. CONCLUSION: The TyG index is positively associated with the risk of nephrolithiasis in males, demonstrating a nonlinear dose-response relationship that becomes especially pronounced at certain index levels. This biomarker could potentially serve as a valuable clinical tool for identifying males who are at a high risk of developing nephrolithiasis, thereby enabling targeted preventive strategies. Further research is urgently needed to explore the underlying mechanisms and to verify the applicability of these results across different populations.
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Glicemia , Nefrolitíase , Triglicerídeos , Humanos , Masculino , Nefrolitíase/sangue , Nefrolitíase/epidemiologia , Estudos Transversais , Triglicerídeos/sangue , Glicemia/análise , Feminino , Adulto , Incidência , Pessoa de Meia-Idade , Fatores de Risco , Modelos LogísticosRESUMO
Atrial septal defect (ASD) is the third most common type of structural congenital heart defect. Patent foramen ovale (PFO) is an anatomical anomaly in up to 25% of the general population. With the innovation of occlusion devices and improvement of transcatheter techniques, percutaneous closure has become a first-line therapeutic alternative for treatment of ASD and PFO. During the past few decades, the development of biodegradable occlusion devices has become a promising direction for transcatheter closure of ASD/PFO due to their biodegradability and improved biocompatibility. The purpose of this review is to comprehensively summarize biodegradable ASD/PFO occlusion devices, regarding device design, materials, biodegradability, and evaluation of animal or clinical experiments (if available). The current challenges and the research direction for the development of biodegradable occluders for congenital heart defects are also discussed.
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BACKGROUND: Intrauterine adhesions (IUAs) jeopardise uterine function in women, which is a great challenge in the clinic. Previous studies have shown that endometrial perivascular cells (En-PSCs) can improve the healing of scarred uteri and that hydroxysafflor yellow A (HSYA) promotes angiogenesis. The purpose of this study was to observe whether the combination of En-PSCs with HSYA could improve the blood supply and fertility in the rat uterus after full-thickness injury. METHODS: En-PSCs were sorted by flow cytometry, and the effect of HSYA on the proliferation and angiogenesis of the En-PSCs was detected using CCK-8 and tube formation assays. Based on a previously reported rat IUA model, the rat uteri were sham-operated, spontaneously regenerated, or treated with collagen-loaded PBS, collagen-loaded HSYA, collagen-loaded En-PSCs, or collagen-loaded En-PSCs with HSYA, and then collected at both 30 and 90 days postsurgery. HE staining and Masson staining were used to evaluate uterine structure and collagen fibre deposition, and immunohistochemical staining for α-SMA and vWF was used to evaluate myometrial regeneration and neovascularization in each group. A fertility assay was performed to detect the recovery of pregnancy function in each group. RNA-seq was performed to determine the potential mechanism underlying En-PSCs/HSYA treatment. Immunofluorescence, tube formation assays, and Western blot were used to validate the molecular mechanism involved. RESULTS: The transplantation of Collagen/En-PSCs/HSYA markedly promoted uterine repair in rats with full-thickness injury by reducing fibrosis, increasing endometrial thickness, regenerating myometrium, promoting angiogenesis, and facilitated live births. RNA sequencing results suggested that En-PSCs/HSYA activated the NRG1/ErbB4 signaling pathway. In vitro tube formation experiments revealed that the addition of an ErbB inhibitor diminished the tube formation ability of cocultured En-PSCs and HUVECs. Western blot results further showed that elevated levels of NRG1 and ErbB4 proteins were detected in the Collagen/En-PSCs/HSYA group compared to the Collagen/En-PSCs group. These collective results suggested that the beneficial effects of the transplantation of Collagen/En-PSCs/HSYA might be attributed to the modulation of the NRG1/ErbB4 signaling pathway. CONCLUSIONS: The combination of En-PSCs/HSYA facilitated morphological and functional repair in rats with full-thickness uterine injury and may promote endometrial angiogenesis by regulating the NRG1/ErbB4 signaling pathway.
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Chalcona , Endométrio , Quinonas , Útero , Animais , Feminino , Ratos , Endométrio/efeitos dos fármacos , Endométrio/metabolismo , Humanos , Útero/efeitos dos fármacos , Útero/metabolismo , Chalcona/análogos & derivados , Chalcona/farmacologia , Quinonas/farmacologia , Quinonas/uso terapêutico , Ratos Sprague-Dawley , Neovascularização Fisiológica/efeitos dos fármacos , Células-Tronco/metabolismo , Células-Tronco/efeitos dos fármacos , Transplante de Células-Tronco/métodos , Proliferação de Células/efeitos dos fármacos , Regeneração/efeitos dos fármacosRESUMO
OBJECTIVE: In this study, multimodal magnetic resonance imaging (MRI) imaging was used to deeply analyze the changes of hippocampal subfields perfusion and function in patients with type 2 diabetes mellitus (T2DM), aiming to provide image basis for the diagnosis of hippocampal-related nerve injury in patients with T2DM. METHODS: We recruited 35 patients with T2DM and 40 healthy control subjects (HCs). They underwent resting-state functional MRI (rs-fMRI), arterial spin labeling (ASL) scans, and a series of cognitive tests. Then, we compared the differences of two groups in the cerebral blood flow (CBF) value, amplitude of low-frequency fluctuation (ALFF) value, and regional homogeneity (ReHo) value of the bilateral hippocampus subfields. RESULTS: The CBF values of cornu ammonis area 1 (CA1), dentate gyrus (DG), and subiculum in the right hippocampus of T2DM group were significantly lower than those of HCs. The ALFF values of left hippocampal CA3, subiculum, and bilateral hippocampus amygdala transition area (HATA) were higher than those of HCs in T2DM group. The ReHo values of CA3, DG, subiculum, and HATA in the left hippocampus of T2DM group were higher than those of HCs. In the T2DM group, HbAc1 and FINS were negatively correlated with imaging characteristics in some hippocampal subregions. CONCLUSION: This study indicates that T2DM patients had decreased perfusion in the CA1, DG, and subiculum of the right hippocampus, and the right hippocampus subiculum was associated with chronic hyperglycemia. Additionally, we observed an increase in spontaneous neural activity within the left hippocampal CA3, subiculum, and bilateral HATA regions, as well as an enhanced local neural coordination in the left hippocampal CA3, DG, HATA, and subiculum among patients with type 2 diabetes, which may reflect an adaptive compensation for cognitive decline. However, this compensation may decline with the exacerbation of metabolic disorders.
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Circulação Cerebrovascular , Diabetes Mellitus Tipo 2 , Hipocampo , Imageamento por Ressonância Magnética , Humanos , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Masculino , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/fisiopatologia , Circulação Cerebrovascular/fisiologia , Pessoa de Meia-Idade , Adulto , Descanso/fisiologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/diagnóstico por imagemRESUMO
Celastrol (CEL), an active compound isolated from the root of Tripterygium wilfordii, exhibits broad anticancer activities. However, its poor stability, narrow therapeutic window and numerous adverse effects limit its applications in vivo. In this study, an adenosine triphosphate (ATP) activatable CEL-Fe(III) chelate was designed, synthesized, and then encapsulated with a reactive oxygen species (ROS)-responsive polymer to obtain CEL-Fe nanoparticles (CEL-Fe NPs). In normal tissues, CEL-Fe NPs maintain structural stability and exhibit reduced systemic toxicity, while at the tumor site, an ATP-ROS-rich tumor microenvironment, drug release is triggered by ROS, and antitumor potency is restored by competitive binding of ATP. This intelligent CEL delivery system improves the biosafety and bioavailability of CEL for cancer therapy. Such a CEL-metal chelate strategy not only mitigates the challenges associated with CEL but also opens avenues for the generation of CEL derivatives, thereby expanding the therapeutic potential of CEL in clinical settings.
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Trifosfato de Adenosina , Triterpenos Pentacíclicos , Pró-Fármacos , Espécies Reativas de Oxigênio , Triterpenos Pentacíclicos/farmacologia , Triterpenos Pentacíclicos/química , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Trifosfato de Adenosina/metabolismo , Humanos , Animais , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Linhagem Celular Tumoral , Triterpenos/química , Triterpenos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Quelantes/química , Quelantes/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Microambiente Tumoral/efeitos dos fármacos , Liberação Controlada de Fármacos , Nanopartículas/química , Ensaios Antitumorais Modelo de Xenoenxerto , Compostos Férricos/químicaRESUMO
PURPOSE: To evaluate the impact of two different parameters (body position and distension medium) on the rectal sensory test in patients with functional constipation and provide data support for the development of standardized operating procedures in clinical practice. METHODS: Based on a single-center process of the rectal sensory test, 39 patients with functional constipation were recruited for rectal sensory test under different body positions and distension mediums. RESULTS: Among the items of the Constipation Scoring System, the score of frequency of bowel movements showed a negative correlation with the first constant sensation volume (r = -0.323, P = 0.045). Conversely, the score of painful evacuation effort showed a positive correlation with the desire to defecate volume (r = 0.343, P = 0.033). There was a statistically significant difference in the first constant sensation volume (when the distension medium was gas) measured in different body positions (left lateral position, sitting position, squatting position), and the data measured in the squatting position were significantly higher than those in left lateral position (P < 0.05). In terms of research on distension medium, it was found that the first constant sensation volume measured in the squatting position (when the distension medium was water) was significantly lower than that of gas (P < 0.05). CONCLUSION: For patients with functional constipation, there are differences in the results of rectal sensory tests between body positions and distension mediums. When conducting multicenter studies, it is necessary to unify the standard operating procedure (SOP) for operational details to ensure consistency and reliability of the test results.
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Constipação Intestinal , Posicionamento do Paciente , Reto , Humanos , Constipação Intestinal/fisiopatologia , Constipação Intestinal/diagnóstico , Feminino , Reto/fisiopatologia , Masculino , Adulto , Pessoa de Meia-Idade , Posicionamento do Paciente/métodos , Defecação/fisiologia , Sensação/fisiologia , Idoso , Adulto JovemRESUMO
OBJECTIVES: Our objective was to explore the safety and efficacy of a graphene oxide-loaded rapamycin-coated self-expandable metallic airway stent (GO@RAPA-SEMS) in a rabbit model. METHODS: The dip coating method was used to develop a GO@RAPA-SEMS and a poly(lactic-co-glycolic)-acid loaded rapamycin-coated self-expandable metallic airway stent (PLGA@RAPA-SEMS). The surface structure was evaluated using a scanning electronic microscope. The in vitro drug-release profiles of the 2 stents were explored and compared. In the animal study, a total of 45 rabbits were randomly divided into 3 groups and underwent 3 kinds of stent placements. Computed tomography was performed to evaluate the degree of stenosis at 1, 2 and 3 months after the stent operation. Five rabbits in each group were sacrificed after the computed tomography scan. The stented trachea and blood were collected for further pathological analysis and laboratory testing. RESULTS: The in vitro drug-release study revealed that GO@RAPA-SEMS exhibited a sudden release on the first day and maintained a certain release rate on the 14th day. The PLGA@RAPA-SEMS exhibited a longer sustained release time. All 45 rabbits underwent successful stent placement. Pathological results indicated that the granulation tissue thickness in the GO@RAPA-SEMS group was less than that in the PLGA@RAPA-SEMS group. The TUNEL and hypoxia-inducible factor-1α staining results support the fact that the granulation inhibition effect in the GO@RAPA-SEMS group was greater than that in the PLGA@RAPA-SEMS group. CONCLUSIONS: GO@RAPA-SEMS effectively inhibited stent-related granulation tissue hyperplasia.
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Stents Farmacológicos , Tecido de Granulação , Grafite , Sirolimo , Animais , Coelhos , Grafite/administração & dosagem , Sirolimo/administração & dosagem , Sirolimo/farmacologia , Tecido de Granulação/efeitos dos fármacos , Tecido de Granulação/patologia , Hiperplasia/prevenção & controle , Stents Metálicos Autoexpansíveis , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Materiais Revestidos Biocompatíveis , Modelos Animais de Doenças , Traqueia/efeitos dos fármacos , Traqueia/patologiaRESUMO
OBJECTIVE: Precancerous metaplasia transition to dysplasia poses a risk for subsequent intestinal-type gastric adenocarcinoma. However, the molecular basis underlying the transformation from metaplastic to cancerous cells remains poorly understood. DESIGN: An integrated analysis of genes associated with metaplasia, dysplasia was conducted, verified and characterised in the gastric tissues of patients by single-cell RNA sequencing and immunostaining. Multiple mouse models, including homozygous conditional knockout Klhl21-floxed mice, were generated to investigate the role of Klhl21 deletion in stemness, DNA damage and tumour formation. Mass-spectrometry-based proteomics and ribosome sequencing were used to elucidate the underlying molecular mechanisms. RESULTS: Kelch-like protein 21 (KLHL21) expression progressively decreased in metaplasia, dysplasia and cancer. Genetic deletion of Klhl21 enhances the rapid proliferation of Mist1+ cells and their descendant cells. Klhl21 loss during metaplasia facilitates the recruitment of damaged cells into the cell cycle via STAT3 signalling. Increased STAT3 activity was confirmed in cancer cells lacking KLHL21, boosting self-renewal and tumourigenicity. Mechanistically, the loss of KLHL21 promotes PIK3CB mRNA translation by stabilising the PABPC1-eIF4G complex, subsequently causing STAT3 activation. Pharmacological STAT3 inhibition by TTI-101 elicited anticancer effects, effectively impeding the transition from metaplasia to dysplasia. In patients with gastric cancer, low levels of KLHL21 had a shorter survival rate and a worse response to adjuvant chemotherapy. CONCLUSIONS: Our findings highlighted that KLHL21 loss triggers STAT3 reactivation through PABPC1-mediated PIK3CB translational activation, and targeting STAT3 can reverse preneoplastic metaplasia in KLHL21-deficient stomachs.
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Low back pain (LBP) has become a leading cause of disability worldwide. Astrocyte activation in the spinal cord plays an important role in the maintenance of latent sensitization of dorsal horn neurons in LBP. However, the role of spinal c-Jun N-terminal kinase (JNK) in astrocytes in modulating pain behavior of LBP model rats and its neurobiological mechanism have not been elucidated. Here, we investigate the role of the JNK signaling pathway on hypersensitivity and anxiety-like behavior caused by repetitive nerve growth factor (NGF) injections in male non-specific LBP model rats. LBP was produced by two injections (day 0, day 5) of NGF into multifidus muscle of the low backs of rats. We observed prolonged mechanical and thermal hypersensitivity in the low backs or hindpaws. Persistent anxiety-like behavior was observed, together with astrocyte, p-JNK, and neuronal activation and upregulated expression of monocyte chemoattractant protein-1 (MCP-1), and chemokine (C-X-C motif) ligand 1 (CXCL1) proteins in the spinal L2 segment. Second, the JNK inhibitor SP600125 was intrathecally administrated in rats from day 10 to day 12. It attenuated mechanical and thermal hypersensitivity of the low back or hindpaws and anxiety-like behavior. Meanwhile, SP600125 decreased astrocyte and neuronal activation and the expression of MCP-1 and CXCL1 proteins. These results showed that hypersensitivity and anxiety-like behavior induced by NGF in LBP rats could be attenuated by the JNK inhibitor, together with downregulation of spinal astrocyte activation, neuron activation, and inflammatory cytokines. Our results indicate that intervening with the spinal JNK signaling pathway presents an effective therapeutic approach to alleviating LBP.
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Ansiedade , Dor Lombar , Sistema de Sinalização das MAP Quinases , Ratos Sprague-Dawley , Animais , Masculino , Ratos , Ansiedade/etiologia , Dor Lombar/metabolismo , Dor Lombar/etiologia , Antracenos/farmacologia , Antracenos/uso terapêutico , Hiperalgesia/metabolismo , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Fator de Crescimento Neural/metabolismo , Medula Espinal/metabolismo , Quimiocina CCL2/metabolismo , Quimiocina CCL2/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismoRESUMO
OBJECTIVE: The aim of this study was to develop and validate prognostic models for predicting overall survival in individuals with gastric carcinoma, specifically focusing on both negative and positive lymphatic metastasis. METHODS: A total of 1650 patients who underwent radical gastric surgery at Shanxi Cancer Hospital between May 2002 and December 2020 were included in the analysis. Multiple Cox Proportional Hazards analysis was performed to identify key variables associated with overall survival in both negative and positive lymphatic metastasis cases. Internal validation was conducted using bootstrapping to assess the prediction accuracy of the models. Calibration curves were used to demonstrate the accuracy and consistency of the predictions. The discriminative abilities of the prognostic models were evaluated and compared with the 8th edition of AJCC-TNM staging using Harrell's Concordance index, decision curve analysis, and time-dependent receiver operating characteristic curves. RESULTS: The nomogram for node-negative lymphatic metastasis included variables such as age, pT stage, and maximum tumor diameter. The C-index for this model in internal validation was 0.719, indicating better performance compared to the AJCC 8th edition TNM staging. The nomogram for node-positive lymphatic metastasis included variables such as gender, age, maximum tumor diameter, neural invasion, Lauren classification, and expression of Her-2, CK7, and CD56. The C-index for this model was 0.674, also outperforming the AJCC 8th edition TNM staging. Calibration curves, time-dependent receiver operating characteristic curves, and decision curve analysis for both nomograms demonstrated excellent prediction ability. Furthermore, significant differences in prognosis between low- and high-risk groups supported the models' strong risk stratification performance. CONCLUSION: This study provides valuable risk stratification models for lymphatic metastasis in gastric carcinoma, encompassing both node-positive and negative cases. These models can help identify low-risk individuals who may not require further intervention, while high-risk individuals can benefit from targeted therapies aimed at addressing lymphatic metastasis.
Assuntos
Gastrectomia , Metástase Linfática , Nomogramas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/mortalidade , Feminino , Masculino , Gastrectomia/mortalidade , Pessoa de Meia-Idade , Taxa de Sobrevida , Prognóstico , Estadiamento de Neoplasias , Idoso , Seguimentos , Estudos Retrospectivos , Fatores de Risco , Curva ROC , Detecção Precoce de Câncer/métodosRESUMO
As an important class of detoxifying enzymes, glutathione S-transferases (GSTs) are pivotal in decreasing insecticide toxicity to insects. Periplaneta americana GSTd1 (PaGSTd1) has been verified as a key enzyme in detoxifying pyrethroid insecticides, but its detoxification capability against a broader spectrum of insecticides has never been investigated. It is revealed that PaGSTd1 expression showed a rapid and significant increase upon exposure to various insecticides (organophosphates, neonicotinoids, and fipronil). Subsequent in vitro metabolic assays indicated that organophosphates, particularly chlorpyrifos-methyl, can be effectively metabolized by PaGSTd1. Further knockdown of PaGSTd1 via RNA interference significantly heightened the susceptibility of P. americana to chlorpyrifos-methyl, underscoring the enzyme's key role in detoxifying chlorpyrifos-methyl. Additionally, this study confirmed that PaGSTd1 cannot mitigate insecticide toxicity through countering oxidative stress. Collectively, these findings elucidate the involvement of PaGSTd1 in the detoxification processes for organophosphates, offering a comprehensive insight into the metabolic mechanisms mediated by GSTs in P. americana. This research provides a foundational understanding for managing GSTs-mediated metabolic resistance in this species, which is crucial for effective pest control strategies.