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INTRODUCTION: Whether 10-day short-course vonoprazan-amoxicillin dual therapy (VA-dual) is noninferior to the standard 14-day bismuth-based quadruple therapy (B-quadruple) against Helicobacter pylori eradication has not been determined. This trial aimed to compare the eradication rate, adverse events, and compliance of 10-day VA-dual regimen with standard 14-day B-quadruple regimen as first-line H. pylori treatment. METHODS: This prospective randomized clinical trial was performed at 3 institutions in eastern China. A total of 314 treatment-naive, H. pylori -infected patients were randomly assigned in a 1:1 ratio to either 10-day VA-dual group or 14-day B-quadruple group. Eradication success was determined by 13 C-urea breath test at least 4 weeks after treatment. Eradication rates, adverse events, and compliance were compared between groups. RESULTS: Eradication rates of VA-dual and B-quadruple groups were 86.0% and 89.2% ( P = 0.389), respectively, by intention-to-treat (ITT) analysis; 88.2% and 91.5% ( P = 0.338), respectively, by modified ITT analysis; and 90.8% and 91.3% ( P = 0.884), respectively, by per-protocol (PP) analysis. The efficacy of the VA-dual remained noninferior to B-quadruple therapy in all ITT, modified ITT, and PP analyses. The incidence of adverse events in the VA-dual group was significantly lower compared with that in the B-quadruple group ( P < 0.001). Poor compliance contributed to eradication failure in the VA-dual group ( P < 0.001), while not in the B-quadruple group ( P = 0.110). DISCUSSION: The 10-day VA-dual therapy provided satisfactory eradication rates of >90% (PP analysis) and lower rates of adverse events compared with standard 14-day B-quadruple therapy as first-line H. pylori therapy. TRAIL REGISTRATION NUMBER: ChiCTR2300070100.
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Infecções por Helicobacter , Helicobacter pylori , Pirróis , Sulfonamidas , Humanos , Amoxicilina/uso terapêutico , Bismuto/uso terapêutico , Bismuto/efeitos adversos , Antibacterianos , Infecções por Helicobacter/tratamento farmacológico , Estudos Prospectivos , Quimioterapia Combinada , Adesão à Medicação , Resultado do Tratamento , Inibidores da Bomba de Prótons/efeitos adversosRESUMO
Carbon-based catalysts are found to be promising metal-free species for aerobic oxidative desulfurization of fuel oil. Thus, a proper approach to promote their catalytic performances is very much in demand. In this contribution, a heteroatom bridging strategy is proposed to enhance the catalytic activities of carbon-based catalysts. As proof of the strategy, a series of boron (B)-doped graphite catalysts were synthesized. Detailed characterizations showed that the hetero-B atoms were uniformly dispersed in graphite. More importantly, it was found that the doped B atoms functioned as a bridge for electron transfer. With the existence of the heteroatom bridge, the activation of oxygen by graphite during the catalytic oxidation process was enhanced remarkably, leading to an ultradeep oxidative desulfurization performance. Moreover, the catalyst can be readily recycled five times without a significant decrease in desulfurization performance.
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BACKGROUND: Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder involving gut-brain interactions with limited effective treatment options. Vitamin D deficiency is commonly observed in patients with IBS, but whether vitamin D supplementation ameliorates IBS is controversial in randomized controlled trials. The present systematic review and meta-analysis explored the efficacy of vitamin D supplementation in patients with IBS. METHODS: We performed a systematic search of potentially relevant publications from PubMed, EMBASE, the Cochrane Central Register of Controlled Studies and the Web of Science up until January 2022. We assessed the weighted mean difference (WMD) and 95% confidence interval (95% CI) of the IBS severity scoring system (IBS-SSS), IBS quality of life (IBS-QoL) and IBS total score (IBS-TS) before and after vitamin D supplementation intervention. RESULTS: We included four randomized, placebo-controlled trials involving 335 participants. The differences in IBS-SSS score between participants in the intervention group and the placebo group increased after intervention (WMD: -55.55, 95% CI: -70.22 to -40.87, I2 = 53.7%, after intervention; WMD: -3.17, 95% CI: -18.15 to 11.81, I2 = 0.0%, before intervention). Participants receiving vitamin D supplementation showed greater improvement in IBS-SSS after intervention than participants receiving placebo treatment (WMD: -84.21, 95% CI: -111.38 to -57.05, I2 = 73.2%; WMD: -28.29, 95% CI: -49.95 to -6.62, I2 = 46.6%, respectively). Vitamin D supplementation was also superior to placebo in IBS-QoL improvement (WMD: 14.98, 95% CI: 12.06 to 17.90, I2 = 0.0%; WMD: 6.55, 95% CI: -2.23 to 15.33, I2 = 82.7%, respectively). Sensitivity analyses revealed an unstable pooled effect on IBS-TS in participants receiving vitamin D supplementation. Therefore, we did not evaluate the efficacy of vitamin D intervention in IBS-TS. CONCLUSIONS: This systematic review and meta-analysis suggested that vitamin D supplementation was superior to placebo for IBS treatment.
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Síndrome do Intestino Irritável , Deficiência de Vitamina D , Suplementos Nutricionais , Humanos , Síndrome do Intestino Irritável/tratamento farmacológico , Qualidade de Vida , Vitamina D/uso terapêutico , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/tratamento farmacológico , VitaminasRESUMO
Hexagonal boron nitride has been regarded to be an efficient catalyst in aerobic oxidation fields, but limited by the less-exposed active sites. In this contribution, we proposed a simple green liquid nitrogen gas exfoliation strategy for preparation of porous monolayer nanosheets (BN-1). Owing to the reduced layer numbers, decreased lateral sizes and artificially-constructed pores, increased exposure of active sites was expected, further contributed to an enhanced aerobic oxidative desulfurization (ODS) performance up to â¼98% of sulfur removal, achieving ultra-deep desulfurization. This work not only introduced an excellent catalyst for aerobic ODS, but also provided a strategy for construction of some other highly-efficient monolayer two-dimensional materials for enhanced catalytic performance.
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Nature has invented photoreceptor proteins that are involved in sensing and response to light in living organisms. Genetic code expansion (GCE) technology has provided new tools to transform light insensitive proteins into novel photoreceptor proteins. It is achieved by the site-specific incorporation of unnatural amino acids (Uaas) that carry light sensitive moieties serving as "pigments" that react to light via photo-decaging, cross-linking, or isomerization. Over the last two decades, various proteins including ion channels, GPCRs, transporters, and kinases have been successfully rendered light responsive owing to the functionalities of Uaas. Very recently, Cas9 protein has been engineered to enable light activation of genomic editing by CRISPR. Those novel proteins have not only led to discoveries of dynamic protein conformational changes with implications in diseases, but also facilitated the screening of ligand-protein and protein-protein interactions of pharmacological significance. This review covers the genetic editing principles for genetic code expansion and design concepts that guide the engineering of light-sensitive proteins. The applications have brought up a new concept of "optoproteomics" that, in contrast to "optogenetics," aims to combine optical methods and site-specific proteomics for investigating and intervening in biological functions.
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Aminoácidos/química , Optogenética/métodos , Engenharia de Proteínas/métodos , Proteômica/métodos , Aminoácidos/genética , Animais , Edição de Genes , Código Genético , Humanos , Mutagênese Sítio-Dirigida , Fotoquímica/métodos , RNA de Transferência , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
Objective: Circular ribose nucleic acids (circRNAs) are implicated in tumor progression and drug resistance of prostate cancer (PCa). The current work explored the function of circ_0005203 (circTHSD4) in the malignancy and docetaxel (DTX) resistance of PCa. Methods: circTHSD4 expression within PCa as well as matched non-carcinoma samples was measured through real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). In addition, a subcellular fraction assay was conducted to determine circTHSD4 subcellular localization within PCa cells. In addition, we performed a Western blot (WB) assay to detect high-mobility-group A2 protein (HMGA2) levels. Besides, functional associations of two molecules were investigated through dual luciferase reporter assay. Cell Counting Kit (CCK)-8, colony formation together with Transwell assay was conducted to assess malignant phenotypes of PCa cells, whereas flow cytometry was performed to determine cell apoptosis. Furthermore, a xenograft mouse model was constructed to verify the effect of circTHSD4 on the carcinogenesis of PCa cells. Results: According to RT-qPCR results, circTHSD4 was up-regulated within PCa tissues and cells, which predicted the dismal prognostic outcome of PCa cases. circTHSD4 silencing within PCa cells markedly suppressed cell growth, migration, and colony formation. circTHSD4 silencing remarkably elevated PCa cell apoptosis and carcinogenesis within the xenograft model. Further, circTHSD4 silencing enhanced docetaxel (DTX) sensitivity in PCa cells. Furthermore, we demonstrated that circTHSD4 modulated the malignancy of PCa cells by regulating HMGA2 expression through sponging miR-203. Conclusion: Together, our findings suggest that circTHSD4 overexpression could promote the malignant phenotype and DTX resistance in PCa through the regulation of the miR-203/HMGA2 axis.
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MicroRNAs , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Docetaxel/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Carcinogênese , Apoptose , Proliferação de Células , Modelos Animais de Doenças , MicroRNAs/genética , Linhagem Celular TumoralRESUMO
In recent years, the incidence of breast cancer has gradually increased, and the research on it has become a hot spot in the scientific community. Central neurons play an important role in breast cancer. This study aims to explore the application of gene expression profile data mining in the study of shared function between central neurons and breast cancer, and focuses on the expression of EMID1 protein antibody. The study collected biomedical images and gene expression profile data of breast cancer patients. Then, we use image processing and analysis technology to extract and analyze features of biomedical images to obtain quantitative features of breast cancer. Gene expression profile data were preprocessed and analyzed to obtain information about breast cancer related genes. Integrating and fusing biomedical images and gene expression profile data, and exploring the sharing function between central neurons and breast cancer through data mining algorithms and statistical analysis methods. The results showed that the expression of EMID1 protein was high in breast cancer tissues, and the expression pattern was similar to that of central neurons. Further functional studies have shown that EMID1 protein is involved in the regulation of proliferation and invasion of breast cancer cells. By regulating the expression level of EMID1 protein, we observed that the proliferation and invasion ability of breast cancer cells were significantly affected. The research results show that through the comprehensive analysis of biomedical images and gene expression profile data, we found the sharing function between central neurons and breast cancer. The central neuronal cell marker genes EMID1 and GREB1L may be used as key biomarkers to regulate the pathogenesis of breast cancer and affect the occurrence and development of breast cancer.
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Recent studies have shown that cellular levels of polyamines (PAs) are significantly altered in neurodegenerative diseases. Evidence from in vivo animal and in vitro cell experiments suggests that the cellular levels of various PAs may play important roles in the central nervous system through the regulation of oxidative stress, mitochondrial metabolism, cellular immunity, and ion channel functions. Dysfunction of PA metabolism related enzymes also contributes to neuronal injury and cognitive impairment in many neurodegenerative diseases. Therefore, in the current work, evidence was collected to determine the possible associations between cellular levels of PAs, and related enzymes and the development of several neurodegenerative diseases, which could provide a new idea for the treatment of neurodegenerative diseases in the future.
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Doenças Neurodegenerativas , Poliaminas , Animais , Poliaminas/metabolismo , Estresse Oxidativo , Mitocôndrias/metabolismo , Apoptose , Doenças Neurodegenerativas/metabolismoRESUMO
Assembly of macromolecular complexes at correct cellular sites is crucial for cell function. Nuclear pore complexes (NPCs) are large cylindrical assemblies with eightfold rotational symmetry, built through hierarchical binding of nucleoporins (Nups) forming distinct subcomplexes. Here, we uncover a role of ubiquitin-associated protein 2-like (UBAP2L) in the assembly and stability of properly organized and functional NPCs at the intact nuclear envelope (NE) in human cells. UBAP2L localizes to the nuclear pores and facilitates the formation of the Y-complex, an essential scaffold component of the NPC, and its localization to the NE. UBAP2L promotes the interaction of the Y-complex with POM121 and Nup153, the critical upstream factors in a well-defined sequential order of Nups assembly onto NE during interphase. Timely localization of the cytoplasmic Nup transport factor fragile X-related protein 1 (FXR1) to the NE and its interaction with the Y-complex are likewise dependent on UBAP2L. Thus, this NPC biogenesis mechanism integrates the cytoplasmic and the nuclear NPC assembly signals and ensures efficient nuclear transport, adaptation to nutrient stress, and cellular proliferative capacity, highlighting the importance of NPC homeostasis at the intact NE.
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Proteínas de Transporte , Membrana Nuclear , Poro Nuclear , Humanos , Transporte Ativo do Núcleo Celular , Células HeLa , Homeostase , Glicoproteínas de Membrana , Membrana Nuclear/metabolismo , Poro Nuclear/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas de Transporte/metabolismoRESUMO
Formation of fluid-filled lumina by epithelial tissues is essential for organ development. How cells control the hydraulic and cortical forces to control lumen morphology is not well understood. Here, we quantified the mechanical role of tight junctions in lumen formation using MDCK-II cysts. We found that the paracellular ion barrier formed by claudin receptors is not required for the hydraulic inflation of a lumen. However, the depletion of the zonula occludens scaffold resulted in lumen collapse and folding of apical membranes. Combining quantitative measurements of hydrostatic lumen pressure and junctional tension with modeling enabled us to explain lumen morphologies from the pressure-tension force balance. Tight junctions promote lumen inflation by decreasing cortical tension via the inhibition of myosin. In addition, our results suggest that excess apical area contributes to lumen opening. Overall, we provide a mechanical understanding of how epithelial cells use tight junctions to modulate tissue and lumen shape.
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Optogenetics combined with protein engineering based on natural lightsensitive dimerizing proteins has evolved as a powerful strategy to study cellular functions. The present study focused on tropomyosin kinase receptors (Trks) that have been engineered to be lightsensitive. Trk belongs to the superfamily of receptor tyrosine kinases (RTKs), which are singlepass transmembrane receptors that are activated by natural ligands and serve crucial roles in cellular growth, differentiation, metabolism and motility. However, functional variations exist among receptors fused with lightsensitive proteins. The present study proposed a signal transduction model for lightinduced receptor activation. This model is based on analysis of previous lightinduced Trk receptors reported to date and comparisons to the activation mechanism of natural receptors. In this model, quantitative differences on the dimerization induced from either toptobottom or bottomtoup may lead to the varying amplitude of intracellular signals. We hypothesize that the toptobottom propagation is more favourable for activation and yields better results compared with the bottomtotop direction. The careful delineation of the dimerization mechanisms finetuning activation will guide future design for an optimum cellular output with the precision of light.
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Fatores de Crescimento Neural/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Dimerização , Humanos , Luz , Transdução de Sinal Luminoso , Modelos Biológicos , Receptor de Insulina/química , Receptor de Insulina/metabolismo , Receptor trkA/química , Receptor trkA/metabolismoRESUMO
AIMS: Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease whose molecular mechanisms remain unclear. This study aimed to explore the role and mechanisms of microRNA-376b-3p in NAFLD. MATERIALS AND METHODS: We used a microarray to reveal hepatic microRNA expression profiles and validated their expression in cellular and mouse models via qRT-PCR. In vitro, the expression of microRNA-376b-3p was increased by a microRNA-376b-3p mimic and decreased by a microRNA-376b-3p inhibitor. The role and potential mechanisms of microRNA-376b-3p in NAFLD were investigated in mice injected with lentiviral vectors before high-fat diet (HFD) feeding, and the direct target gene was explored using a dual-luciferase reporter gene assay and confirmed by Western blotting. KEY FINDINGS: Microarray analysis and subsequent validation showed that the expression of microRNA-376b-3p was downregulated by nearly 90 % in the livers of HFD-fed mice and by >50 % in free fatty acid-stimulated hepatocytes. Overexpression of microRNA-376b-3p markedly ameliorated hepatic lipid accumulation, which was attributable to an increase in fatty acid oxidation. Conversely, inhibition of miR-376b-3p exhibited the opposite effects. The luciferase reporter assay indicated that Fgfr1 is a direct target gene of miR-376b-3p. Fgfr1 intervention eliminated the effect of miR-376b-3p on the lipid oxidation pathway and hepatocyte steatosis, which suggests that miR-376b-3p regulates fatty acid oxidation by targeting Fgfr1 to influence NAFLD development. SIGNIFICANCE: miR-376b-3p was downregulated in NAFLD and has a novel regulatory role in lipid oxidation through a miR-376b-3p-Fgfr1-dependent mechanism. Thus, miR-376b-3p may serve as a potential diagnostic marker or therapeutic target for NAFLD.
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MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica , Ácidos Graxos não Esterificados/metabolismo , Hepatócitos/metabolismo , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismoRESUMO
Objective: To examine the expression of transforming growth factor-ß (TGF-ß) in the periapical granulation tissue and serum of patients with chronic apical periodontitis and to conduct immunohistochemical analysis so as to explore the relationship between TGF-ß and the degree of periapical lesions. Methods: Periapical granulation tissues of 20 cases of chronic apical periodontitis were collected as the experimental group. Healthy gingival tissues without eruption of third molars of 5 cases were collected as the control group. Immunohistochemistry, enzyme-linked immunosorbent assay, and real-time PCR (RT-PCR) were utilized to determine the expression of TGF-ß mRNA and protein, and the difference in the expression of TGF-ß was compared between groups. In the experimental group, oral CBCT was taken to measure the periapical bone resorption area. Spearman's correlation method was applied to analyze the correlation between TGF-ß protein and gene expression levels and periapical bone resorption area. Results: Immunohistochemistry and enzyme-linked immunosorbent assay demonstrated that the expression of TGF-ß protein in chronic apical periodontitis tissue and serum was higher than that in the controls (P < 0.05). RT-PCR revealed that the expression of TGF-ß mRNA was higher in chronic apical periodontitis tissue than that of the controls (P < 0.05). Spearman's correlation analysis showed that in the experimental group, the mRNA expression of TGF-ß was positively correlated with the periapical bone resorption area (P < 0.01), and the protein expression level was not correlated with the periapical bone resorption area (P < 0.05). Conclusion: The increased expression of TGF-ß in the periapical granulation tissue and serum of patients with chronic apical periodontitis has a certain correlation with the progression of periapical periodontitis. The correlation between TGF-ß at the mRNA level and the degree of early stage disease as well as the high expression of TGF-ß in inflammatory cells in immunohistochemistry have confirmed that TGF-ß promotes bone resorption in early periapical periodontitis, and its mechanism of action deserves further investigation.
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Periodontite Periapical , Fator de Crescimento Transformador beta , Humanos , Periodontite Periapical/metabolismo , Periodontite Periapical/patologia , Fator de Crescimento Transformador beta/metabolismoRESUMO
BACKGROUND: Fine particulate matter (particulate matter 2.5, PM2.5) is considered one of the harmful factors to neuronal functions. Apoptosis is one of the mechanisms of neuronal injury induced by PM2.5. Methylcobalamine (MeCbl) has been shown to have anti-apoptotic and neuroprotective effects. OBJECTIVE: The current work tried to explore the neuroprotective effects and mechanisms that MeCbl protects mice against cognitive impairment and neuronal apoptosis induced by chronic real-time PM2.5 exposure. METHODS: Twenty-four 6-week-old male C57BL/6 mice were exposed to ambient PM2.5 and fed with MeCbl for 6 months. Morris water maze was used to evaluate the changes of spatial learning and memory ability in mice. PC12 cells and primary hippocampal neurons were applied as the in vitro model. Cell viability, cellular reactive oxygen species (ROS) and the expressions of apoptosis-related proteins were examined. And cells were stained with JC-1 and mitochondrial membrane potential was evaluated. RESULTS: In C57BL/6 mice, MeCbl supplementation alleviated cognitive impairment and apoptosis-related protein expression induced by PM2.5 exposure. In in vitro cell model, MeCbl supplementation could effectively rescue the downregulation of cell viability induced by PM2.5, and inhibited the increased levels of ROS, cellular apoptosis, and the expressions of apoptosis related proteins related to PM2.5 treatment, which may be associated with modulation of mitochondrial function. CONCLUSION: MeCbl treatment alleviated cognitive impairment and neuronal apoptosis induced by PM2.5 both in vivo and in vitro. The mechanism for the neuroprotective effects of MeCbl may at least be partially dependent on the regulation of mitochondrial apoptosis.
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Disfunção Cognitiva , Fármacos Neuroprotetores , Animais , Apoptose/fisiologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Material Particulado/toxicidade , Ratos , Espécies Reativas de Oxigênio/metabolismo , Vitamina B 12/análogos & derivadosRESUMO
Chronic periodontitis caused by Porphyromonas gingivalis (P. gingivalis) infection generally lasts for a lifetime. The long-term existence and development of P. gingivalis infection gradually aggravate the accumulation of inflammatory signals and toxic substances in the body. Recent evidence has revealed that P. gingivalis infection may be relevant to some central nervous system (CNS) diseases. The current work collects information and tries to explore the possible relationship between P. gingivalis infection and CNS diseases, including the interaction or pathways between peripheral infection and CNS injury, and the underlying neurotoxic mechanisms.
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Doenças do Sistema Nervoso Central/fisiopatologia , Inflamação/complicações , Periodontite/complicações , Porphyromonas gingivalis/patogenicidade , Epigenômica , HumanosRESUMO
Membrane protein interactions are crucial for diverse biological processes. We report the application of genetic code expansion in combination with photo-crosslinking chemistry, as we termed "optoproteomics", to identify proteins interacting with the human L-type membrane amino acid transporter 3 (LAT3, also known as SLC43A1). The site-specifically incorporated photo-cross-linker p-azido-L-phenylalanine (AzF), which reacts with proteins in their proximity, enabled the capture of weak and transient partners of LAT3 in living cells. We identify 11 unique interacting proteins which are light-sensitive and 19 unique proteins that are site-specific, validating the approach and providing insights into the LAT3 protein-protein interaction network currently unavailable.
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Sistemas de Transporte de Aminoácidos Básicos/química , Proteômica , Reagentes de Ligações Cruzadas/química , Humanos , Fenilalanina/química , Processos Fotoquímicos , Ligação ProteicaRESUMO
Epithelial tissues of the developing embryos elongate by different mechanisms, such as neighbor exchange, cell elongation, and oriented cell division. Since autonomous tissue self-organization is influenced by external cues such as morphogen gradients or neighboring tissues, it is difficult to distinguish intrinsic from directed tissue behavior. The mesoscopic processes leading to the different mechanisms remain elusive. Here, we study the spontaneous elongation behavior of spreading circular epithelial colonies in vitro. By quantifying deformation kinematics at multiple scales, we report that global elongation happens primarily due to cell elongations, and its direction correlates with the anisotropy of the average cell elongation. By imposing an external time-periodic stretch, the axis of this global symmetry breaking can be modified and elongation occurs primarily due to orientated neighbor exchange. These different behaviors are confirmed using a vertex model for collective cell behavior, providing a framework for understanding autonomous tissue elongation and its origins.
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Divisão Celular , Células Epiteliais/citologia , Epitélio/embriologia , Morfogênese , Animais , Fenômenos Biomecânicos , Células CACO-2 , Cães , Humanos , Células Madin Darby de Rim CaninoRESUMO
Imaging dynamics of cellular morphogenesis with high spatial-temporal resolution in 3D is challenging, due to the low spatial resolution along the optical axis and photo-toxicity. However, some cellular structures are planar and hence 2D imaging should be sufficient, provided that the structure of interest can be oriented with respect to the optical axis of the microscope. Here, we report a 3D microfabrication method which positions and orients cell divisions very close to the microscope coverglass. We use this approach to study cytokinesis in fission yeasts and polarization to lumen formation in mammalian epithelial cells. We show that this method improves spatial resolution on range of common microscopies, including super-resolution STED. Altogether, this method could shed new lights on self-organization phenomena in single cells and 3D cell culture systems.
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Citocinese , Imageamento Tridimensional/métodos , Microtecnologia/métodos , Animais , Cães , Células HeLa , Humanos , Células Madin Darby de Rim Canino , Microscopia de Fluorescência , Polímeros/química , Fatores de TempoRESUMO
Fine particulate matter 2.5 (PM2.5), one of the main components of air pollutants, seriously threatens human health. Possible neuronal dysfunction induced by PM2.5 has received extensive attention. However, there is little evidence for the specific biochemical mechanism of neuronal injury induced by PM2.5. Moreover, the pathway for PM2.5 transport from peripheral circulation to the central nervous system (CNS) is still unclear. In the current work, C57BL/6 mice were chronically exposed to ambient PM2.5 for 3, 6, 9, and 12 months. Exposure to ambient PM2.5 resulted in a significant reduction of cognitive ability in mice by Morris water maze test. PM2.5 exposure induced a neuroinflammatory reaction after cognitive impairment, while inflammation in the hypothalamus and olfactory bulb tissue occurred earlier. The expression levels of integrity tight junction proteins in the blood-brain barrier (BBB) were reduced by PM2.5 exposure. Pulmonary inflammation occurred much earlier and diminished at later stage of PM2.5 exposure. The results indicated that chronic exposure to ambient PM2.5 led to cognitive decline in mice; CNS dysfunction may be due to neuroinflammatory reactions; the reduced integrity of the BBB allowed the influence of pulmonary inflammation to neuronal alterations. The work may provide promising therapeutic or preventive targets for air pollution-induced neurodegenerative disease.