RESUMO
Modern retrosynthetic analysis in organic chemistry is based on the principle of polar relationships between functional groups to guide the design of synthetic routes1. This method, termed polar retrosynthetic analysis, assigns partial positive (electrophilic) or negative (nucleophilic) charges to constituent functional groups in complex molecules followed by disconnecting bonds between opposing charges2-4. Although this approach forms the basis of undergraduate curriculum in organic chemistry5 and strategic applications of most synthetic methods6, the implementation often requires a long list of ancillary considerations to mitigate chemoselectivity and oxidation state issues involving protecting groups and precise reaction choreography3,4,7. Here we report a radical-based Ni/Ag-electrocatalytic cross-coupling of substituted carboxylic acids, thereby enabling an intuitive and modular approach to accessing complex molecular architectures. This new method relies on a key silver additive that forms an active Ag nanoparticle-coated electrode surface8,9 in situ along with carefully chosen ligands that modulate the reactivity of Ni. Through judicious choice of conditions and ligands, the cross-couplings can be rendered highly diastereoselective. To demonstrate the simplifying power of these reactions, concise syntheses of 14 natural products and two medicinally relevant molecules were completed.
Assuntos
Produtos Biológicos , Técnicas de Química Sintética , Descarboxilação , Eletroquímica , Eletrodos , Preparações Farmacêuticas , Ácidos Carboxílicos/química , Nanopartículas Metálicas/química , Oxirredução , Prata/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Níquel/química , Ligantes , Preparações Farmacêuticas/síntese química , Preparações Farmacêuticas/química , Eletroquímica/métodos , Técnicas de Química Sintética/métodosRESUMO
The inhomogeneous refractive indices of biological tissues blur and distort single-molecule emission patterns generating image artifacts and decreasing the achievable resolution of single-molecule localization microscopy (SMLM). Conventional sensorless adaptive optics methods rely on iterative mirror changes and image-quality metrics. However, these metrics result in inconsistent metric responses and thus fundamentally limit their efficacy for aberration correction in tissues. To bypass iterative trial-then-evaluate processes, we developed deep learning-driven adaptive optics for SMLM to allow direct inference of wavefront distortion and near real-time compensation. Our trained deep neural network monitors the individual emission patterns from single-molecule experiments, infers their shared wavefront distortion, feeds the estimates through a dynamic filter and drives a deformable mirror to compensate sample-induced aberrations. We demonstrated that our method simultaneously estimates and compensates 28 wavefront deformation shapes and improves the resolution and fidelity of three-dimensional SMLM through >130-µm-thick brain tissue specimens.
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Aprendizado Profundo , Microscopia , Óptica e Fotônica , EncéfaloRESUMO
Xylan is one of the major hemicelluloses in plant cell walls and its xylosyl backbone is often decorated at O-2 with glucuronic acid (GlcA) and/or methylglucuronic acid (MeGlcA) residues. The GlcA/MeGlcA side chains may be further substituted with 2-O-arabinopyranose (Arap) or 2-O-galactopyranose (Gal) residues in some plant species, but the enzymes responsible for these substitutions remain unknown. During our endeavor to investigate the enzymatic activities of Arabidopsis MUR3-clade members of the GT47 glycosyltransferase family, we found that one of them was able to transfer Arap from UDP-Arap onto O-2 of GlcA side chains of xylan, and thus it was named xylan 2-O-arabinopyranosyltransferase 1 (AtXAPT1). The function of AtXAPT1 was verified in planta by its T-DNA knockout mutation showing a loss of the Arap substitution on xylan GlcA side chains. Further biochemical characterization of XAPT close homologs from other plant species demonstrated that while the poplar ones had the same catalytic activity as AtXAPT1, those from Eucalyptus, lemon-scented gum, sea apple, 'Ohi'a lehua, duckweed and purple yam were capable of catalyzing both 2-O-Arap and 2-O-Gal substitutions of xylan GlcA side chains albeit with differential activities. Sequential reactions with XAPTs and glucuronoxylan methyltransferase 3 (GXM3) showed that XAPTs acted poorly on MeGlcA side chains, whereas GXM3 could efficiently methylate arabinosylated or galactosylated GlcA side chains of xylan. Furthermore, molecular docking and site-directed mutagenesis analyses of Eucalyptus XAPT1 revealed critical roles of several amino acid residues at the putative active site in its activity. Together, these findings establish that XAPTs residing in the MUR3 clade of family GT47 are responsible for 2-O-arabinopyranosylation and 2-O-galactosylation of GlcA side chains of xylan.
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Exocytosis and endocytosis are tightly coupled. In addition to initiating exocytosis, Ca2+ plays critical roles in exocytosisendocytosis coupling in neurons and nonneuronal cells. Both positive and negative roles of Ca2+ in endocytosis have been reported; however, Ca2+ inhibition in endocytosis remains debatable with unknown mechanisms. Here, we show that synaptotagmin-1 (Syt1), the primary Ca2+ sensor initiating exocytosis, plays bidirectional and opposite roles in exocytosisendocytosis coupling by promoting slow, small-sized clathrin-mediated endocytosis but inhibiting fast, large-sized bulk endocytosis. Ca2+-binding ability is required for Syt1 to regulate both types of endocytic pathways, the disruption of which leads to inefficient vesicle recycling under mild stimulation and excessive membrane retrieval following intense stimulation. Ca2+-dependent membrane tubulation may explain the opposite endocytic roles of Syt1 and provides a general membrane-remodeling working model for endocytosis determination. Thus, Syt1 is a primary bidirectional Ca2+ sensor facilitating clathrin-mediated endocytosis but clamping bulk endocytosis, probably by manipulating membrane curvature to ensure both efficient and precise coupling of endocytosis to exocytosis.
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Endocitose , Transmissão Sináptica , Sinaptotagmina I , Cálcio/metabolismo , Endocitose/fisiologia , Exocitose/fisiologia , Neurônios/metabolismo , Sinaptotagmina I/metabolismoRESUMO
Retinoic acid receptor responder protein-1 (RARRES1) is a podocyte-enriched transmembrane protein whose increased expression correlates with human glomerular disease progression. RARRES1 promotes podocytopenia and glomerulosclerosis via p53-mediated podocyte apoptosis. Importantly, the cytopathic actions of RARRES1 are entirely dependent on its proteolytic cleavage into a soluble protein (sRARRES1) and subsequent podocyte uptake by endocytosis, as a cleavage mutant RARRES1 exerted no effects in vitro or in vivo. As RARRES1 expression is upregulated in human glomerular diseases, here we investigated the functional consequence of podocyte-specific overexpression of RARRES1 in mice in the experimental focal segmental glomerulosclerosis and diabetic kidney disease. We also examined the effects of long-term RARRES1 overexpression on slowly developing aging-induced kidney injury. As anticipated, the induction of podocyte overexpression of RARRES1 (Pod-RARRES1WT) significantly worsened glomerular injuries and worsened kidney function in all three models, while overexpression of RARRES1 cleavage mutant (Pod-RARRES1MT) did not. Remarkably, direct uptake of sRARRES1 was also seen in proximal tubules of injured Pod-RARRES1WT mice and associated with exacerbated tubular injuries, vacuolation, and lipid accumulation. Single-cell RNA sequence analysis of mouse kidneys demonstrated RARRES1 led to a marked deregulation of lipid metabolism in proximal tubule subsets. We further identified matrix metalloproteinase 23 (MMP23) as a highly podocyte-specific metalloproteinase and responsible for RARRES1 cleavage in disease settings, as adeno-associated virus 9-mediated knockdown of MMP23 abrogated sRARRES1 uptake in tubular cells in vivo. Thus, our study delineates a previously unrecognized mechanism by which a podocyte-derived protein directly facilitates podocyte and tubular injury in glomerular diseases and suggests that podocyte-specific functions of RARRES1 and MMP23 may be targeted to ameliorate glomerular disease progression in vivo.
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Nefropatias Diabéticas , Progressão da Doença , Glomerulosclerose Segmentar e Focal , Túbulos Renais Proximais , Podócitos , Animais , Humanos , Masculino , Camundongos , Apoptose , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/etiologia , Modelos Animais de Doenças , Endocitose , Glomerulosclerose Segmentar e Focal/patologia , Glomerulosclerose Segmentar e Focal/metabolismo , Glomerulosclerose Segmentar e Focal/genética , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Podócitos/metabolismo , Podócitos/patologiaRESUMO
MAIN CONCLUSION: A member of the rice GT61 clade B is capable of transferring both 2-O-xylosyl and 2-O-arabinosyl residues onto xylan and another member specifically catalyses addition of 2-O-xylosyl residue onto xylan. Grass xylan is substituted predominantly with 3-O-arabinofuranose (Araf) as well as with some minor side chains, such as 2-O-Araf and 2-O-(methyl)glucuronic acid [(Me)GlcA]. 3-O-Arabinosylation of grass xylan has been shown to be catalysed by grass-expanded clade A members of the glycosyltransferase family 61. However, glycosyltransferases mediating 2-O-arabinosylation of grass xylan remain elusive. Here, we performed biochemical studies of two rice GT61 clade B members and found that one of them was capable of transferring both xylosyl (Xyl) and Araf residues from UDP-Xyl and UDP-Araf, respectively, onto xylooligomer acceptors, whereas the other specifically catalysed Xyl transfer onto xylooligomers, indicating that the former is a xylan xylosyl/arabinosyl transferase (named OsXXAT1 herein) and the latter is a xylan xylosyltransferase (named OsXYXT2). Structural analysis of the OsXXAT1- and OsXYXT2-catalysed reaction products revealed that the Xyl and Araf residues were transferred onto O-2 positions of xylooligomers. Furthermore, we demonstrated that OsXXAT1 and OsXYXT2 were able to substitute acetylated xylooligomers, but only OsXXAT1 could xylosylate GlcA-substituted xylooligomers. OsXXAT1 and OsXYXT2 were predicted to adopt a GT-B fold structure and molecular docking revealed candidate amino acid residues at the predicted active site involved in binding of the nucleotide sugar donor and the xylohexaose acceptor substrates. Together, our results establish that OsXXAT1 is a xylan 2-O-xylosyl/2-O-arabinosyl transferase and OsXYXT2 is a xylan 2-O-xylosyltransferase, which expands our knowledge of roles of the GT61 family in grass xylan synthesis.
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Arabidopsis , Oryza , Glicosiltransferases/análise , Oryza/metabolismo , Xilanos/metabolismo , Arabidopsis/metabolismo , Simulação de Acoplamento Molecular , UDP Xilose-Proteína Xilosiltransferase , Poaceae/metabolismo , Parede Celular/metabolismoRESUMO
BACKGROUND: Chronic kidney disease (CKD) is highly prevalent worldwide, and its global burden is substantial and growing. CKD displays a number of features of accelerated senescence. Tubular cell senescence is a common biological process that contributes to CKD progression. Tubulointerstitial inflammation is a driver of tubular cell senescence and a common characteristic of CKD. However, the mechanism by which the interstitial inflammation drives tubular cell senescence remains unclear. This paper aims to explore the role of exosomal miRNAs derived from macrophages in the development of tubular cell senescence. METHODS: Among the identified inflammation-related miRNAs, miR-155 is considered to be one of the most important miRNAs involved in the inflammatory response. Macrophages, the primary immune cells that mediate inflammatory processes, contain a high abundance of miR-155 in their released exosomes. We assessed the potential role of miR-155 in tubular cell senescence and renal fibrosis. We subjected miR-155-/- mice and wild-type controls, as well as tubular epithelial cells (TECs), to angiotensin II (AngII)-induced kidney injury. We assessed kidney function and injury using standard techniques. TECs were evaluated for cell senescence and telomere dysfunction in vivo and in vitro. Telomeres were measured by the fluorescence in situ hybridization. RESULTS: Compared with normal controls, miR-155 was up-regulated in proximal renal tubule cells in CKD patients and mouse models of CKD. Moreover, the expression of miR-155 was positively correlated with the extent of renal fibrosis, eGFR decline and p16INK4A expression. The overexpression of miR-155 exacerbated tubular senescence, evidenced by increased detection of p16INK4A/p21expression and senescence-associated ß-galactosidase activity. Notably, miR-155 knockout attenuates renal fibrosis and tubule cell senescence in vivo. Interestingly, once released, macrophages-derived exosomal miR-155 was internalized by TECs, leading to telomere shortening and dysfunction through targeting TRF1. A dual-luciferase reporter assay confirmed that TRF1 was the direct target of miR-155. Thus, our study clearly demonstrates that exosomal miR-155 may mediate communication between macrophages and TECs, subsequently inducing telomere dysfunction and senescence in TECs. CONCLUSIONS: Our work suggests a new mechanism by which macrophage exosomes are involved in the development of tubule senescence and renal fibrosis, in part by delivering miR-155 to target TRF1 to promote telomere dysfunction. Our study may provide novel strategies for the treatment of AngII-induced kidney injury.
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Senescência Celular , Células Epiteliais , Exossomos , Túbulos Renais , Macrófagos , MicroRNAs , Telômero , MicroRNAs/genética , MicroRNAs/metabolismo , Senescência Celular/genética , Exossomos/metabolismo , Exossomos/genética , Animais , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Macrófagos/metabolismo , Túbulos Renais/patologia , Túbulos Renais/metabolismo , Camundongos , Telômero/genética , Telômero/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Masculino , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Fibrose/genética , Angiotensina IIRESUMO
Biological invasions have become a worldwide problem, and measures to efficiently prevent and control invasions are still in development. Like many other parts of the world, China is undergoing a dramatic increase in plant invasions. Most of the currently 933 established (i.e., naturalized) plant species, of which 214 are categorized as invasive, have been introduced into China for cultivation. It is likely that many of those species are still being traded, particularly online, by plant nurseries. However, studies assessing whether naturalized and invasive species are currently being traded more or less than nonnaturalized aliens are rare. We extracted online-trade information for 13,718 cultivated alien plant taxa on 1688.com, the largest website for domestic B2B in China. We analyzed how the presence in online-nursery catalogs, the number of online nurseries that offerred the species for sale, and the product type (i.e., seeds, live plants and vegetative organs) differed among nonnaturalized, naturalized noninvasive, and invasive species. Compared to nonnaturalized taxa, naturalized noninvasive and invasive taxa were 3.7-5.2 times more likely to be available for purchase. Naturalized noninvasive and invasive taxa were more frequently offered as seeds by online nurseries, whereas nonnaturalized taxa were more frequently offered as live plants. Based on these findings, we propose that, to reduce the further spread of invasive and potentially invasive plants, implementation of plant-trade regulations and a monitoring system of the online horticultural supply chain will be essential.
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Espécies Introduzidas , Plantas , Sementes , Comércio , ChinaRESUMO
Prized for their ability to rapidly generate chemical complexity by building new ring systems and stereocentres1, cycloaddition reactions have featured in numerous total syntheses2 and are a key component in the education of chemistry students3. Similarly, carbon-carbon (C-C) cross-coupling methods are integral to synthesis because of their programmability, modularity and reliability4. Within the area of drug discovery, an overreliance on cross-coupling has led to a disproportionate representation of flat architectures that are rich in carbon atoms with orbitals hybridized in an sp2 manner5. Despite the ability of cycloadditions to introduce multiple carbon sp3 centres in a single step, they are less used6. This is probably because of their lack of modularity, stemming from the idiosyncratic steric and electronic rules for each specific type of cycloaddition. Here we demonstrate a strategy for combining the optimal features of these two chemical transformations into one simple sequence, to enable the modular, enantioselective, scalable and programmable preparation of useful building blocks, natural products and lead scaffolds for drug discovery.
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Carbono/química , Técnicas de Química Sintética , Reação de Cicloadição , Produtos Biológicos/síntese química , Produtos Biológicos/química , Descoberta de DrogasRESUMO
Tubular epithelial cells (TECs) exposed to hypoxia incite tubulointerstitial inflammation (TII), while the exact mechanism is unclear. In this study, we identified that hypoxia evoked tubule injury as evidenced by tubular hypoxia-inducible factor-1α and kidney injury molecule-1 (KIM-1) expression and that renal small extracellular vesicle (sEV) production was increased with the development of TII after ischemia-reperfusion injury (IRI). Intriguingly, KIM-1-positive tubules were surrounded by macrophages and co-localized with sEVs. In vitro, KIM-1 expression and sEV release were increased in hypoxic TECs and the hypoxia-induced inflammatory response was ameliorated when KIM-1 or Rab27a, a master regulator of sEV secretion, was silenced. Furthermore, KIM-1 was identified to mediate hypoxic TEC-derived sEV (Hypo-sEV) uptake by TECs. Phosphatidylserine (PS), a ligand of KIM-1, was present in Hypo-sEVs as detected by nanoflow cytometry. Correspondingly, the inflammatory response induced by exogenous Hypo-sEVs was attenuated when KIM-1 was knocked down. In vivo, exogenous-applied Hypo-sEVs localized to KIM-1-positive tubules and exacerbated TII in IRI mice. Our study demonstrated that KIM-1 expressed by injured tubules mediated sEV uptake via recognizing PS, which participated in the amplification of tubule inflammation induced by hypoxia, leading to the development of TII in ischemic acute kidney injury.
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Vesículas Extracelulares , Traumatismo por Reperfusão , Animais , Camundongos , Células Epiteliais/metabolismo , Vesículas Extracelulares/metabolismo , Hipóxia/metabolismo , Inflamação/metabolismo , Rim/metabolismo , Traumatismo por Reperfusão/metabolismoRESUMO
BACKGROUND: Prophylactic dose of rivaroxaban is often used in treatment of isolated calf muscle vein thrombosis (ICMVT); nevertheless, its effect is less reported. This study aims to evaluate short-term outcomes in patients with ICMVT who received prophylactic dose of rivaroxaban or warfarin therapy. METHODS: A retrospective analysis of 472 ICMVT patients who received 2 different treatment regimens was undertaken. Propensity score matching method was used to balance the confounding effect of baseline clinical data. Chi-squared test and logistic regression analysis were used to compare outcomes (venous thromboembolism events, bleeding events, complete clot resolution) according to the type of treatment regimens before and after propensity score matching. Univariate and multivariable analysis were used to investigate risk factors for incomplete clot resolution of ICMVT after propensity score matching. RESULTS: 242 ICMVT patients received prophylactic dose of rivaroxaban (rivaroxaban group, RG), and 230 received warfarin (warfarin group, WG). After propensity score matching, 156 patients were included in each group; Venous thromboembolism (VTE) events occurred in 14 (9.0%) patients in the RG and 10 (6.4%) in the WG (P = 0.395); no major bleeding events occurred in each group, and clinically relevant nonmajor bleeding events occurred in 5 (3.2%) patients in the RG and 10 (6.4%) in the WG (P = 0.186); complete clot resolution at 3 months occurred in 80 (51.3%) patients in the RG and 100 (64.1%) in the WG (P = 0.022). Logistic regression analysis showed that there were no significant differences between RG and WG in VTE events (odds ratio 1.439, 95% confidence interval 0.619-3.347, P = 0.397) and clinically relevant nonmajor bleeding events (odds ratio 0.483, 95% confidence interval 0.161-1.449, P = 0.194); it revealed that complete clot resolution rate at 3 months was different in the 2 groups (odds ratio 0.589, 95% confidence interval 0.375-0.928, P = 0.022). Treatment regimens (prophylactic dose of rivaroxaban), thrombosis (maximum diameter >7 mm), and risk factors for VTE (nonsurgery risk factors, mainly referring to active malignancy) were risk factors for incomplete clot resolution of ICMVT (P < 0.05). CONCLUSIONS: In this retrospective study with a short-term follow-up, ICMVT patients who received prophylactic dose of rivaroxaban had no significant differences in VTE and bleeding events compared to those who received warfarin therapy (the overall INR >2.0 for >50% of the time); but it was not conducive to complete clot resolution.
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Objective Variations are present in common clinical practices regarding best practice in managing hyperkalaemia (HK), there is therefore a need to establish a multi-specialty approach to optimal renin-angiotension-aldosterone system inhibitors (RAASi) usage and HK management in patients with chronic kidney disease (CKD) & heart failure (HF).This study aimed to establish a multi-speciality approach to the optimal use of RAASi and the management of HK in patients with CKD and HF. Methods A steering expert group of cardiology and nephrology experts across China were convened to discuss challenges to HK management through a nominal group technique. The group then created a list of 41 statements for a consensus questionnaire, which was distributed for a further survey in extended panel group of cardiologists and nephrologists across China. Consensus was assessed using a modified Delphi technique, with agreement defined as "strong" (≥75% and <90%) and "very strong" (≥90%). The steering group, data collection, and analysis were aided by an independent facilitator. Results A total of 150 responses from 21 provinces across China were recruited in the survey. Respondents were comprised of an even split (n=75, 50%) between cardiologists and nephrologists. All 41 statements achieved the 75% consensus agreement threshold, of which 27 statements attained very strong consensus (≥90% agreement) and 14 attained strong consensus (agreement between 75% and 90%). Conclusion Based on the agreement levels from respondents, the steering group agreed a set of recommendations intended to improve patient outcomes in the use of RAASi therapy and HK management in China.
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Consenso , Técnica Delphi , Insuficiência Cardíaca , Hiperpotassemia , Insuficiência Renal Crônica , Humanos , Hiperpotassemia/tratamento farmacológico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/complicações , China , Sistema Renina-Angiotensina/efeitos dos fármacos , Inquéritos e Questionários , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , População do Leste AsiáticoRESUMO
A concise total synthesis of the complex guanidinium toxin KB343 is reported traversing through an unusual sequence of chemoselective transformations and strategic skeletal reorganization. The absolute configuration is confirmed through an enantioselective route, and the structures of all key intermediates and the natural product itself are unassailably confirmed through X-ray crystallographic analysis.
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Produtos Biológicos , Estereoisomerismo , Guanidina , Cristalografia por Raios XRESUMO
Single-molecule localization microscopy is a powerful tool for visualizing subcellular structures, interactions and protein functions in biological research. However, inhomogeneous refractive indices inside cells and tissues distort the fluorescent signal emitted from single-molecule probes, which rapidly degrades resolution with increasing depth. We propose a method that enables the construction of an in situ 3D response of single emitters directly from single-molecule blinking datasets, and therefore allows their locations to be pinpointed with precision that achieves the Cramér-Rao lower bound and uncompromised fidelity. We demonstrate this method, named in situ PSF retrieval (INSPR), across a range of cellular and tissue architectures, from mitochondrial networks and nuclear pores in mammalian cells to amyloid-ß plaques and dendrites in brain tissues and elastic fibers in developing cartilage of mice. This advancement expands the routine applicability of super-resolution microscopy from selected cellular targets near coverslips to intra- and extracellular targets deep inside tissues.
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Encéfalo/metabolismo , Cartilagem/metabolismo , Imageamento Tridimensional/métodos , Microscopia de Fluorescência/métodos , Nanotecnologia/métodos , Placa Amiloide/metabolismo , Imagem Individual de Molécula/métodos , Animais , Encéfalo/patologia , Cartilagem/patologia , Núcleo Celular/metabolismo , Células Cultivadas , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Camundongos , Mitocôndrias/metabolismo , Imagem Molecular/métodos , Poro Nuclear/metabolismo , Placa Amiloide/patologiaRESUMO
BACKGROUND: Tubulointerstitial inflammation (TII) is a critical pathological feature of kidney disease leading to renal fibrosis, and its treatment remains a major clinical challenge. We sought to explore the role of quercetin, a potential exosomes inhibitor, in exosomes release and TII. METHODS: The effects of quercetin on exosomes release and TII were examined by two TII mouse models: the unilateral ureteral obstruction (UUO) models and the LPS-induced mouse models. In vitro, exosomes-mediated crosstalk between tubular epithelial cells (TECs) and macrophages was performed to investigate the mechanisms by which quercetin inhibited exosomes and TII. RESULTS: In this study, we found that exosomes-mediated crosstalk between TECs and macrophages contributed to the development of TII. In vitro, exosomes released from LPS-stimulated TECs induced increased expression of inflammatory cytokines and fibrotic markers in Raw264·7 cells and vice versa. Interestingly, heat shock protein 70 (Hsp70) or Hsp90 proteins could control exosomes release from TECs and macrophages both in vivo and in vitro. Importantly, quercetin, a previously recognized heat shock protein inhibitor, could significantly reduce exosomes release in TII models by down-regulating Hsp70 or Hsp90. Quercetin abrogated exosomes-mediated intercellular communication, which attenuated TII and renal fibrosis accordingly. CONCLUSION: Quercetin could serve as a novel strategy for treatment of tubulointerstitial inflammation by inhibiting the exosomes-mediated crosstalk between tubules and macrophages.
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Exossomos , Quercetina , Camundongos , Animais , Quercetina/farmacologia , Quercetina/uso terapêutico , Exossomos/metabolismo , Lipopolissacarídeos/farmacologia , Inflamação/metabolismo , Macrófagos/metabolismo , Fibrose , Células Epiteliais/metabolismo , Túbulos Renais/metabolismo , Túbulos Renais/patologiaRESUMO
OBJECTIVE: This study aimed to explore the clinical significance of fatty acid transport-related protein (FATRP) in patients with clear cell renal cell carcinoma(ccRCC). METHODS: RNA-seq data and corresponding clinical data of ccRCC were obtained from TCGA data portal. Seventeen key FATRP genes were comprehensively investigated using bioinformatics approaches to systematically investigate their expression patterns in ccRCC. In addition, the correlation between the expression levels of these genes and clinicopathological features in ccRCC was further explored. RESULTS: Among the 17 key FATRP genes, only FABP5, FABP6, and FABP7 could be regarded as ideal biomarkers for ccRCC, as they were highly expressed in ccRCC tumor tissues, and positively correlates with tumor progression and poor prognosis. FABP6 had the highest copy number variations (CNV) events (63.07 %), and ccRCC patients with FABP6 amplification had a better prognosis than the unaltered group. DNA methylation levels of FABP6 and FABP7 were downregulated in ccRCC tumor tissues compared to those in normal tissues. FABP5 showed the opposite results. Moreover, a novel four FATRP gene (FABP1, FABP5, FABP7, FATP2) and three clinical parameter (age, stage, and grade) prediction model was constructed and that comprised a significant independent prognostic signature. CONCLUSIONS: Only a few FATRP genes are upregulated in ccRCC tumor tissue, and positively correlate with tumor progression and poor prognosis. The accuracy of a single gene of these FATRP genes as predictors of progression and prognosis of ccRCC is limited. The performance of the novel prediction model proposed by this study was much better than that of any single gene.
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Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/metabolismo , Neoplasias Renais/metabolismo , Variações do Número de Cópias de DNA , Prognóstico , Ácidos Graxos , Proteínas de Ligação a Ácido Graxo/genéticaRESUMO
Cyclin-dependent kinase 12 (CDK12) plays a critical role in regulating gene transcription. CDK12 inhibition is a potential anticancer therapeutic strategy. However, several clinical trials have shown that CDK inhibitors might cause renal dysfunction and electrolyte disorders. CDK12 is abundant in renal tubular epithelial cells (RTECs), but the exact role of CDK12 in renal physiology remains unclear. Genetic knockout of CDK12 in mouse RTECs causes polydipsia, polyuria, and hydronephrosis. This phenotype is caused by defects in water reabsorption that are the result of reduced Na-K-2Cl cotransporter 2 (NKCC2) levels in the kidney. In addition, CKD12 knockout causes an increase in Slc12a1 (which encodes NKCC2) intronic polyadenylation events, which results in Slc12a1 truncated transcript production and NKCC2 downregulation. These findings provide novel insight into CDK12 being necessary for maintaining renal homeostasis by regulating NKCC2 transcription, which explains the critical water and electrolyte disturbance that occurs during the application of CDK12 inhibitors for cancer treatment. Therefore, there are safety concerns about the clinical use of these new anticancer drugs.
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Antineoplásicos , Simportadores , Animais , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Eletrólitos , Rim/metabolismo , Camundongos , Membro 1 da Família 12 de Carreador de Soluto , Simportadores/genética , ÁguaRESUMO
Introduction: We explored the relationship and the predictive value of serum fibroblast growth factor 21 (FGF21) with all-cause mortality, major adverse cardiovascular events (MACEs) and pneumonia in hemodialysis (HD) patients.Methods: A total of 388 Chinese HD patients from two HD centers were finally enrolled in this prospective cohort study (registration number: ChiCTR 1900028249) between January 2018 and December 2018. Serum FGF21 was detected. Patients were followed up with a median period of 47 months to record the MACEs and pneumonia until death or 31 December 2022.Results: The incidence of all-cause mortality, MACEs and pneumonia in HD patients were 20.6%, 29.6%, and 34.8%, respectively. The optimal cutoffs for FGF21 to predict all-cause mortality, MACEs and pneumonia were 437.57 pg/mL, 216.99 pg/mL and 112.79 pg/mL. Multivariate Cox regression analyses showed that FGF21, as a categorical variable, was an independent predictor for all-cause mortality, MACEs and pneumonia (HR, 3.357, 95% CI, 2.128-5.295, p < 0.001; HR, 1.575, 95% CI, 1.046-2.371, p = 0.029; HR, 1.784; 95% CI, 1.124-2.830; p = 0.014, respectively). The survival nomogram, MACEs-free survival nomogram and pneumonia-free survival nomogram based on FGF21 constructed for individualized assessment of HD patients had a high C-index with 0.841, 0.706 and 0.734.Conclusion: Higher serum FGF21 is an independent predictor of all-cause mortality, MACEs and pneumonia in HD patients.
Assuntos
Fatores de Crescimento de Fibroblastos , Diálise Renal , Humanos , Fatores de Crescimento de Fibroblastos/sangue , Estudos Prospectivos , Diálise Renal/efeitos adversos , População do Leste AsiáticoRESUMO
OBJECTIVES: To compare the effects of cell lysis method and magnetic beads method in forensic DNA identification and to explore these two methods in forensic DNA identification. METHODS: The genome DNA of THP-1 cells in different quantities was extracted by the cell lysis method and magnetic beads method, and the DNA content was quantified by real-time quantitative PCR. The cell lysis method and magnetic beads method were used to type the STR of human blood with different dilution ratios. RESULTS: When the numbers of THP-1 cell were 100, 400 and 800, the DNA content extracted by cell lysis method were (1.219±0.334), (5.081±0.335), (9.332±0.318) ng, respectively; and the DNA content extracted by magnetic beads method were (1.020±0.281), (3.634±0.482), (7.896±0.759) ng, respectively. When the numbers of THP-1 cells were 400 and 800, the DNA content extracted by the cell lysis method was higher than that by the magnetic beads method. The sensitivity of cell lysis method and magnetic beads method was similar in STR typing of human blood at different dilution ratios. Complete STR typing could be obtained at 100, 300 and 500-fold dilutions of blood samples, but could not be detected at 700-fold dilution. STR typing of undiluted human blood could not be detected by cell lysis method. CONCLUSIONS: The cell lysis method is easy to operate and can retain template DNA to the maximum extend. It is expected to be suitable for trace blood evidence tests.
Assuntos
DNA , Medicina Legal , Humanos , DNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Fenômenos Magnéticos , Impressões Digitais de DNA/métodos , Repetições de MicrossatélitesRESUMO
BACKGROUND: Roxadustat (FG-4592) is an oral inhibitor of hypoxia-inducible factor (HIF) prolyl hydroxylase that stimulates erythropoiesis and regulates iron metabolism. In phase 2 studies involving patients with chronic kidney disease, roxadustat increased levels of endogenous erythropoietin to within or near the physiologic range, along with increasing hemoglobin levels and improving iron homeostasis. Additional data are needed regarding the efficacy and safety of roxadustat for the treatment of anemia in patients with chronic kidney disease who are not undergoing dialysis. METHODS: In this phase 3 trial conducted at 29 sites in China, we randomly assigned 154 patients with chronic kidney disease in a 2:1 ratio to receive roxadustat or placebo three times a week for 8 weeks in a double-blind manner. All the patients had a hemoglobin level of 7.0 to 10.0 g per deciliter at baseline. The randomized phase of the trial was followed by an 18-week open-label period in which all the patients received roxadustat; parenteral iron was withheld. The primary end point was the mean change from baseline in the hemoglobin level, averaged over weeks 7 through 9. RESULTS: During the primary-analysis period, the mean (±SD) change from baseline in the hemoglobin level was an increase of 1.9±1.2 g per deciliter in the roxadustat group and a decrease of 0.4±0.8 g per deciliter in the placebo group (P<0.001). The mean reduction from baseline in the hepcidin level (associated with greater iron availability) was 56.14±63.40 ng per milliliter in the roxadustat group and 15.10±48.06 ng per milliliter in the placebo group. The reduction from baseline in the total cholesterol level was 40.6 mg per deciliter in the roxadustat group and 7.7 mg per deciliter in the placebo group. Hyperkalemia and metabolic acidosis occurred more frequently in the roxadustat group than in the placebo group. The efficacy of roxadustat in hemoglobin correction and maintenance was maintained during the 18-week open-label period. CONCLUSIONS: In Chinese patients with chronic kidney disease who were not undergoing dialysis, those in the roxadustat group had a higher mean hemoglobin level than those in the placebo group after 8 weeks. During the 18-week open-label phase of the trial, roxadustat was associated with continued efficacy. (Funded by FibroGen and FibroGen [China] Medical Technology Development; ClinicalTrials.gov number, NCT02652819.).