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Fumonisin B1 (FB1) targets sphingolipid biosynthesis, inhibiting ceramide synthases. In this issue of Structure, Zhang et al.1 determined the cryoelectron microscopic structures of yeast ceramide synthase in complex with FB1 and its acylated derivative, acyl-FB1, revealing a two-step "ping-pong" mechanism for the N-acylation of FB1 and how it inhibits ceramide synthase.
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Microscopia Crioeletrônica , Fumonisinas , Oxirredutases , Fumonisinas/química , Fumonisinas/metabolismo , Oxirredutases/metabolismo , Oxirredutases/química , Oxirredutases/antagonistas & inibidores , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Acilação , Modelos Moleculares , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Esfingolipídeos/metabolismo , Esfingolipídeos/químicaRESUMO
Rehabilitation robots can reproduce the rehabilitation movements of therapists by designed rehabilitation robot control methods to achieve the goal of training the patients' motion abilities. This paper proposes an impedance sliding-mode control method based on stiffness-scheduled law for the rehabilitation robot, which can be applied to rehabilitation training with both active and passive modes. A free-model-based sliding-mode control strategy is developed to avoid model dependence and reduce the system uncertainty caused by limb shaking. Additionally, the stiffness scheduling rule automatically regulates the impedance parameter of the rehabilitation robot based on the force exerted by the patient on the robot such that the rehabilitation training caters to the patient's health condition. The proposed method is compared with the fixed stiffness and variable stiffness impedance methods, and the superiority of the proposed method is proved. Rehabilitation training experiments on an actual rehabilitation robot are provided to demonstrate the feasibility and stability of the proposed method.
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BACKGROUND: Myelodysplastic syndrome (MDS) is a prevalent hematological neoplastic disorder in clinics and its immunopathogenesis has garnered growing interest. Oral and intravenous arsenic agents have long been used to treat hematological malignancies. The main component of oral arsenic is realgar (arsenic disulfide), while arsenic trioxide is the main component of intravenous arsenic. METHODS: This study aimed to assess the effects of ATO and Realgar on the enhancement of peripheral blood, drug safety, and T cell immune status in the NUP98-HOXD13 (NHD13) mice model of MDS, specifically in the peripheral blood, spleen, and liver. RESULTS: The study findings indicate that realgar and arsenic trioxide (ATO) can improve peripheral hemogram in mice, whereas realgar promotes higher peripheral blood cell production than ATO. Furthermore, the clinical administration method and dose did not cause significant toxicity or side effects and thus can be considered safe. Coexistence and interconversion of hyperimmune function and immunosuppression in mice were also observed in this study. In addition, there were interactions between immune cells in the peripheral blood, spleen, and liver to regulate the immune balance of the body and activate immunity via T-cell activation. CONCLUSION: In summary, oral and intravenous arsenic agents are beneficial in improving peripheral hemogram and immunity in mice.
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Trióxido de Arsênio , Arsenicais , Modelos Animais de Doenças , Síndromes Mielodisplásicas , Animais , Trióxido de Arsênio/administração & dosagem , Trióxido de Arsênio/farmacologia , Arsenicais/farmacologia , Arsenicais/administração & dosagem , Camundongos , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/imunologia , Sulfetos/farmacologia , Sulfetos/administração & dosagem , Dissulfetos/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Baço/efeitos dos fármacos , Baço/imunologiaRESUMO
BACKGROUND AND AIMS: Long noncoding RNAs (lncRNAs) play important roles in the progression of atherosclerosis. In this study, we identified an uncharacterized lncRNA, Liver Expressions by PSRC1 Induced Specifically (LEPIS). This study aimed to clarify the mechanism though which LEPIS affects atherosclerosis (AS). METHODS: The expression of LEPIS and its potential target, tropomodulin 4 (TMOD4), was increased in the livers of ApoE-/- mice fed a high-fat diet (HFD). An ApoE-/- mouse model in which LEPIS or TMOD4 was overexpressed in the liver was established. The plaque load in the aorta was assessed, plasma was collected to measure blood lipid levels, and the liver was collected to study cholesterol metabolism. RESULTS: We found that both LEPIS and TMOD4 increased the AS burden and reduced hepatic cholesterol levels. A further study revealed that LEPIS and TMOD4 affected the expression of genes related to hepatic cholesterol homeostasis, including proprotein convertase subtilisin/kexin type 9 (PCSK9) and low-density lipoprotein receptor (LDLR), which are closely related to hypercholesterolemia. Mechanistically, human antigen R (HuR), an RNA-binding protein (RBP), was shown to be critical for the regulation of TMOD4 by LEPIS. Furthermore, we found that verexpression of LEPIS promoted the shuttling of HuR from the nucleus to the cytoplasm, enhanced the stability of TMOD4 mRNA, and in turn promoted the expression of TMOD4. In addition, TMOD4 was found to affect intracellular cholesterol levels through PCSK9. CONCLUSIONS: These results suggest that the LEPIS-HuR-TMOD4 axis is a potential intervention target for dysregulated hepatic cholesterol homeostasis and AS and may provide the basis for further reductions in the circulating LDL-C concentration and arterial plaque burden.
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Aterosclerose , Colesterol , Modelos Animais de Doenças , Homeostase , Fígado , Camundongos Knockout para ApoE , Animais , Humanos , Masculino , Camundongos , Doenças da Aorta/metabolismo , Doenças da Aorta/genética , Doenças da Aorta/patologia , Aterosclerose/metabolismo , Aterosclerose/genética , Aterosclerose/patologia , Colesterol/metabolismo , Colesterol/sangue , Dieta Hiperlipídica , Proteína Semelhante a ELAV 1/metabolismo , Proteína Semelhante a ELAV 1/genética , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Placa Aterosclerótica , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertase 9/genética , Receptores de LDL/genética , Receptores de LDL/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
Lipid droplet, an intracellular lipid reservoir, is vital for energy metabolism and signal transmission in cells. The viscosity directly affects the metabolism of lipid droplets, and the abnormal viscosity is associated with the occurrence and development of various diseases. Therefore, it is indispensable to develop techniques that can detect viscosity changes in intracellular lipid droplets. Based on twisted intramolecular charge transfer (TICT) mechanism, a novel small-molecule lipid droplet-targeted viscosity fluorescence probe PPF-1 was designed. The probe was easy to synthesize, it had a large Stokes shift, stable optical properties, and low bio-toxicity. Compared to being in methanol solution, the fluorescence intensity of PPF-1 in glycerol solution was increased 26.7-fold, and PPF-1 showed excellent ability to target lipid droplets. Thus, the probe PPF-1 could provide an effective means of detecting viscosity changes of lipid droplets and was of great value for physiological diagnosis of related diseases, pathological analysis, and medical research.
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Corantes Fluorescentes , Gotículas Lipídicas , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Viscosidade , Gotículas Lipídicas/química , Humanos , Estrutura Molecular , Imagem Óptica , Espectrometria de FluorescênciaRESUMO
Sphingomyelin (SM) has key roles in modulating mammalian membrane properties and serves as an important pool for bioactive molecules. SM biosynthesis is mediated by the sphingomyelin synthase (SMS) family, comprising SMS1, SMS2 and SMS-related (SMSr) members. Although SMS1 and SMS2 exhibit SMS activity, SMSr possesses ceramide phosphoethanolamine synthase activity. Here we determined the cryo-electron microscopic structures of human SMSr in complexes with ceramide, diacylglycerol/phosphoethanolamine and ceramide/phosphoethanolamine (CPE). The structures revealed a hexameric arrangement with a reaction chamber located between the transmembrane helices. Within this structure, a catalytic pentad E-H/D-H-D was identified, situated at the interface between the lipophilic and hydrophilic segments of the reaction chamber. Additionally, the study unveiled the two-step synthesis process catalyzed by SMSr, involving PE-PLC (phosphatidylethanolamine-phospholipase C) hydrolysis and the subsequent transfer of the phosphoethanolamine moiety to ceramide. This research provides insights into the catalytic mechanism of SMSr and expands our understanding of sphingolipid metabolism.
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Microscopia Crioeletrônica , Modelos Moleculares , Esfingomielinas , Transferases (Outros Grupos de Fosfato Substituídos) , Humanos , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo , Transferases (Outros Grupos de Fosfato Substituídos)/química , Esfingomielinas/metabolismo , Esfingomielinas/química , Esfingomielinas/biossíntese , Ceramidas/metabolismo , Ceramidas/química , Etanolaminas/metabolismo , Etanolaminas/química , Fosfatidiletanolaminas/metabolismo , Fosfatidiletanolaminas/química , Diglicerídeos/metabolismo , Diglicerídeos/química , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/química , Proteínas de MembranaRESUMO
Across five studies, we present the preliminary technical validation of an infant-wearable platform, LittleBeats™, that integrates electrocardiogram (ECG), inertial measurement unit (IMU), and audio sensors. Each sensor modality is validated against data from gold-standard equipment using established algorithms and laboratory tasks. Interbeat interval (IBI) data obtained from the LittleBeats™ ECG sensor indicate acceptable mean absolute percent error rates for both adults (Study 1, N = 16) and infants (Study 2, N = 5) across low- and high-challenge sessions and expected patterns of change in respiratory sinus arrythmia (RSA). For automated activity recognition (upright vs. walk vs. glide vs. squat) using accelerometer data from the LittleBeats™ IMU (Study 3, N = 12 adults), performance was good to excellent, with smartphone (industry standard) data outperforming LittleBeats™ by less than 4 percentage points. Speech emotion recognition (Study 4, N = 8 adults) applied to LittleBeats™ versus smartphone audio data indicated a comparable performance, with no significant difference in error rates. On an automatic speech recognition task (Study 5, N = 12 adults), the best performing algorithm yielded relatively low word error rates, although LittleBeats™ (4.16%) versus smartphone (2.73%) error rates were somewhat higher. Together, these validation studies indicate that LittleBeats™ sensors yield a data quality that is largely comparable to those obtained from gold-standard devices and established protocols used in prior research.
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Postura , Caminhada , Adulto , Humanos , Movimento (Física) , Caminhada/fisiologia , Postura/fisiologia , Posição Ortostática , Algoritmos , Fenômenos BiomecânicosRESUMO
OBJECTIVE: Aging becomes the most predominant risk factor for all age-associated pathological conditions with the increase of life expectancy and the aggravation of social aging. Slowing down the speed of aging is considered an effective way to improve health, but so far, effective anti-aging methods are relatively lacking. METHODS: Anemonin (ANE) was screened from eight existing small-molecule compounds by cell viability assay. The function of ANE was determined by the analysis of cell proliferation, ß -galactosidase (SA-ß -Gal) activity, cell cycle, SASP secretion, NAD+/NADH ratio, and other aging-related indicators. The targets of ANE were predicted by Drug Target Prediction System (DTPS) and Swiss Targe Prediction System. The effect of ANE on PARP-1-NAD+-SIRT1 signaling pathway was assessed by quantitative reverse-transcription polymerase chain reaction (RT-PCR), Western blot, PARP1, NAD+ and SIRT1 activity detection. RESULTS: ANE can delay cell senescence; PARP1 is one of the targets of ANE and plays a crucial role in ANE anti-aging; ANE release more NAD+ by inhibiting PARP1 activity, thereby conversely promoting the function of SIRT1 and delay cell senescence. CONCLUSIONS: Our study indicates that ANE can delay cellular senescence through the PARP1-NAD+-SIRT1 signaling pathway, which may be considered as an effective anti-aging strategy.
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NAD , Sirtuína 1 , Humanos , Sirtuína 1/genética , Sirtuína 1/metabolismo , Sirtuína 1/farmacologia , NAD/metabolismo , NAD/farmacologia , Diploide , Senescência Celular/fisiologia , Transdução de Sinais , Fibroblastos/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Poli(ADP-Ribose) Polimerase-1/farmacologiaRESUMO
Bortezomib (BTZ), a selective proteasome inhibitor, exhibits a significant efficacy in the therapy of multiple myeloma (MM) partly through triggering endoplasmic reticulum (ER) stress-dependent apoptosis. However, sensitivity to BTZ varies greatly among patients. ER stress functions as a double-edged sword in regulating cell survival depending on cell context and ER stress extent. The major aim of this study was to investigate whether GRP78 inhibitor, HA15, increased the therapeutic effect of BTZ on MM to through further increasing ER stress and shifting the balance towards cell apoptosis. The biological role of BTZ and HA15 was assessed using Cell counting kit- (CCK-) 8, colony formation, and Terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labelling (TUNEL) assay. We found that BTZ combined with HA15 remarkably decreased MM cell viability more effective than BTZ monotherapy, though low dose of HA15 did not exhibit a significant cytotoxicity to MM cells. BTZ combined with HA15 also repressed colony formation ability of MM cell and accelerated MM cell apoptosis compared with BTZ monotherapy. Mechanistically, HA15 synergized with BTZ to trigger ER stress, as evidence by significantly increased expression of ER stress markers (GRP78, ATF4, CHOP, and XBP1). Importantly, unfolded protein response (UPR) inhibitor significantly damaged the effect of BTZ combined with HA15 on accelerating MM cell death. In vivo, combination treatment with BTZ and HA15 inhibited tumor growth more effective than BTZ alone, whereas these effects were blocked by UPR inhibitor. Taken together, these results demonstrate that ER stress is a critical pathway in regulating MM cell survival, and that combination treatment with BTZ and HA15 may be an effective strategy to treat MM patients that fail to respond to BTZ monotherapy.
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Recently, fluorescent covalent staining methods have been developed for visualization of anatomical structures in cells and tissues. Coupled with expansion microscopy, these stains revealed various ultrastructural details. However, the covalently stainable chemical groups have been limited to amines, carbohydrates, and thiols. Here, we developed procedures for covalently labeling tissues for carboxylate and phosphate groups, utilizing carbodiimide crosslinker chemistry. In porcine kidney tissues, the carboxylate and phosphate stain provides 1.8-4.8-fold higher signal intensity than those from the three existing stains. In cancer cells, such stain allows 2-8-fold more accurate identification of nucleoli than the amine stain. In expansion microscopy samples, such stain reveals a variety of sub-cellular structures in tissues when combined with the amine stain. Such stain also allows imaging of lipid-based structures in cultured cells. With these advantages, this new covalent staining method further expands the toolset for fluorescent visualization of histology.
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Corantes , Fosfatos , Animais , Suínos , Coloração e Rotulagem , Microscopia , Aminas , Corantes FluorescentesRESUMO
This paper thoroughly investigates material characterization, reliability evaluation, fabrication, and assembly processes of additively manufactured flexible packaging and reconfigurable on-package antenna arrays for next-generation 5G/mmWave wearable and conformal applications. The objective is to bridge the technology gap in current Flexible Hybrid Electronics (FHE) designs at mmWave frequencies and address the challenges of establishing future design standards for additively manufactured flexible packages and System-on-Package (SoP) integrated modules. Multiple 3D printed flexible materials have been characterized for their electrical and mechanical properties over the 5G/mmW frequency band (26-40 GHz), and the inkjet printed interconnects on 3D printed Polypropylene (PP) substrates demonstrated excellent electrical and mechanical performance during a 10,000-time cyclic bending test over typical wearable flexible radii down to 1 inch. A proof-of-concept flexible on-package phased array with an integrated microfluidic cooling channel on 3D printed substrates was fabricated and measured, demonstrating [Formula: see text] beam steering capability with efficient cooling. The proposed reconfigurable design and low-temperature fabrication approach using additive manufacturing can be widely applied to next-generation highly-complex on-demand FHE, flexible multi-chip-module integration, and on-package phased-array modules for 5G/mmWave wearable and conformal smart skin, digital twin and massive MIMO applications.
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Covalent organic frameworks (COFs) have received lots of attention due to their multiple advantages such as high specific surface area, controlled pore size, and excellent stability. When detecting food contaminants, the matrix effect brought by complex food samples can significantly affect the accuracy of the results. How to attenuate matrix effect has always been a major challenge. Utilizing the advantages of COFs and applying them to detect food contaminants is currently a key research direction. The aim of this work is to provide a systematic summary of sample pretreatment techniques and detection techniques combined with COFs, which include almost all current techniques combined with COFs. In addition, the principles of combining COFs with different techniques are explained. Finally, the research foci and development direction of COFs in food contaminant detection are discussed. This is an important reference for the future development of food safety and the design of COFs.
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Alimentos , Estruturas Metalorgânicas , Inocuidade dos AlimentosRESUMO
NiOx-based inverted perovskite solar cells (PSCs) have attracted growing attention due to their low cost and large-scale application potential. However, the efficiency and stability of inverted planar heterojunction PSCs is still unsatisfactory owing to insufficient charge-extraction caused by undesirable interfacial contact between perovskite and NiOx hole transport layers (HTLs). Herein an interfacial passivation strategy with guanidinium salts (guanidinium thiocyanate (GuASCN), guanidine hydrobromide (GuABr), guanidine hydriodate (GuAI)) as passivator is employed to solve this problem. We systematically study the effect of various guanidinium salts on the crystallinity, morphology, and photophysical properties of perovskite films. Guanidine salt as interfacial passivator can decrease interface resistance, reduce carrier non-radiative recombination, and boost carrier extraction. Notably, the GuABr-treated unencapsulated devices can still maintain more than 90 % of their initial PCE after aging for 1600â h at 16-25 °C and 35 %-50 % relative humidity in ambient conditions. This work reveals the significance of counterions in improving the photovoltaic performance and stability of PSCs.
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Herein, we describe a novel methodology for the regio- and stereoselective convergent synthesis of 2-amino-2-deoxy-dithioglycosides via one-pot relay glycosylation of 3-O-acetyl-2-nitroglucal donors. This unique organo-catalysis relay glycosylation features excellent site- and stereoselectivity, good to excellent yields, mild reaction conditions, and broad substrate scope. 2-Amino-2-deoxy-glucosides/mannosides bearing 1,3-dithio-linkages were efficiently obtained from 3-O-acetyl-2-nitroglucal donors in both stepwise and one-pot glycosylation protocols. The dithiolated O-antigen of E. coli serogroup 64 was successfully synthesized using this newly developed method.
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Previous investigations mainly focused on the associations of dietary fatty acids with colorectal cancer (CRC) risk, which ignored gene-environment interaction and mechanisms interpretation. We conducted a case-control study (751 cases and 3058 controls) and a prospective cohort study (125 021 participants) to explore the associations between dietary fatty acids, genetic risks, and CRC. Results showed that high intake of saturated fatty acid (SFA) was associated with a higher risk of CRC than low SFA intake (HR =1.22, 95% CI:1.02-1.46). Participants at high genetic risk had a greater risk of CRC with the HR of 2.48 (2.11-2.91) than those at low genetic risk. A multiplicative interaction of genetic risk and SFA intake with incident CRC risk was found (PInteraction = 7.59 × 10-20 ), demonstrating that participants with high genetic risk and high SFA intake had a 3.75-fold greater risk of CRC than those with low genetic risk and low SFA intake. Furthermore, incorporating PRS and SFA into traditional clinical risk factors improved the discriminatory accuracy for CRC risk stratification (AUC from 0.706 to 0.731). Multi-omics data showed that exposure to SFA-rich high-fat dietary (HFD) can responsively induce epigenome reprogramming of some oncogenes and pathological activation of fatty acid metabolism pathway, which may contribute to CRC development through changes in gut microbiomes, metabolites, and tumor-infiltrating immune cells. These findings suggest that individuals with high genetic risk of CRC may benefit from reducing SFA intake. The incorporation of SFA intake and PRS into traditional clinical risk factors will help improve high-risk sub-populations in individualized CRC prevention.
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Neoplasias Colorretais , Gorduras na Dieta , Humanos , Estudos Prospectivos , Estudos de Casos e Controles , Gorduras na Dieta/efeitos adversos , Fatores de Risco , Ácidos Graxos/efeitos adversos , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/induzido quimicamenteRESUMO
BACKGROUND: Atherosclerosis (AS), the main pathological basis of life-threatening cardiovascular disease, is essentially caused by chronic macrophage inflammation. Overexpression of proline/serine-rich coiled-coil protein 1 (PSRC1) reduces macrophage inflammatory responses and delays AS development. However, the exact mechanism of PSRC1 is unclear. METHODS: Proteins interacting with PSRC1 were screened by proteomics in RAW264.7 cells, followed by RT-qPCR, immunoprecipitation and immunofluorescence to explore the specific mechanistic pathways affecting inflammation. CRISPR-Cas9 constructs for PSRC1-/- ApoE-/- (DKO) mice and high-fat diet-fed ApoE-/- and DKO mice were used for AS models for in vivo experiments. Upstream transcription factors of PSRC1 were predicted by ATAC-seq, ChIP-seq and UCSC, and the regulatory mechanism was verified by ChIP-qPCR and dual luciferase assays. Peripheral blood serum and monocytes were collected from coronary artery disease (CAD) patients and non-CAD patients. RESULTS: Increased binding of ANXA2 to PSRC1 in macrophages under oxidized low-density lipoprotein stimulation and decreased release of ANXA2 to the extracellular compartment were observed. Knockdown of ANXA2 in AS model mice delayed AS progression. Knockdown of ANXA2 in DKO mice reversed the AS-promoting effect of PSRC1 knockdown. Mechanistically, ANXA2 promotes STAT3 phosphorylation, which in turn promotes inflammatory responses. In addition, SP1 is a PSRC1 upstream repressive transcription factor, and the SP1 inhibitor mithramycin (Mith) elevated PSRC1 expression and exerted anti-AS effects in AS model mice. Patients with CAD had considerably greater serum levels of ANXA2 than those without CAD, and Mith reduced the secretion of ANXA2 in peripheral blood monocytes of CAD patients. CONCLUSION: In macrophages, PSRC1 can interact with ANXA2 to inhibit its extracellular release and delay AS development. SP1 is an upstream transcription factor of PSRC1 and inhibits the transcription of PSRC1. The SP1 inhibitor Mith can elevate PSRC1 levels and slow AS progression while reducing ANXA2 release from monocytes in CAD patients. Mith is expected to be a new agent for AS treatment.
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Anexina A2 , Aterosclerose , Doença da Artéria Coronariana , Fosfoproteínas , Animais , Camundongos , Aterosclerose/metabolismo , Inflamação , Macrófagos/metabolismo , Prolina , Serina , Fatores de Transcrição/metabolismo , Fosfoproteínas/metabolismo , Camundongos Knockout para ApoERESUMO
The cell maintains its intracellular pH in a narrow physiological range and disrupting the pH-homeostasis could cause dysfunctional metabolic states. Anion exchanger 2 (AE2) works at high cellular pH to catalyze the exchange between the intracellular HCO3- and extracellular Cl-, thereby maintaining the pH-homeostasis. Here, we determine the cryo-EM structures of human AE2 in five major operating states and one transitional hybrid state. Among those states, the AE2 shows the inward-facing, outward-facing, and intermediate conformations, as well as the substrate-binding pockets at two sides of the cell membrane. Furthermore, critical structural features were identified showing an interlock mechanism for interactions among the cytoplasmic N-terminal domain and the transmembrane domain and the self-inhibitory effect of the C-terminal loop. The structural and cell-based functional assay collectively demonstrate the dynamic process of the anion exchange across membranes and provide the structural basis for the pH-sensitive pH-rebalancing activity of AE2.
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Proteínas de Transporte de Ânions , Antiporters , Humanos , Antiportadores de Cloreto-Bicarbonato , Concentração de Íons de Hidrogênio , Membrana Celular/metabolismo , Homeostase , Antiporters/metabolismo , Proteínas de Transporte de Ânions/metabolismo , Cloretos/metabolismoRESUMO
Three zeolitic imidazolate frameworks (ZIFs) materials including ZIF-8 (H2O), ZIF-8 (methanol) and ZIF-L were synthesized and applied to the adsorption and detoxification of gossypol in cottonseed oil. The characterization results showed three ZIFs materials had good crystal structure, thermal stability and high specific surface area. The ZIFs materials had also good adsorption performance for gossypol and their adsorption processes can be described by the pseudo-second-order adsorption kinetic models. Adsorption isotherm analysis indicated that Langmuir model expressed a better conformity than Freundlich model, suggesting that the adsorption was the single-layer adsorption on a uniform site. Furthermore, the spiked experiment showed that the detoxification rate of ZIFs materials in vegetable oil was 72-86 %. A satisfied detoxification rate of 50-70 % was found in the detoxification experiment of real cottonseed oil samples. Therefore, these results demonstrate the great potential of using ZIFs materials as detoxification in cottonseed oil.
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Gossipol , Nanopartículas , Zeolitas , Imidazóis/química , Óleo de Sementes de Algodão , Zeolitas/química , AdsorçãoRESUMO
As the major component of cell membranes, phosphatidylcholine (PC) is synthesized de novo in the Kennedy pathway and then undergoes extensive deacylation-reacylation remodeling via Lands' cycle. The re-acylation is catalyzed by lysophosphatidylcholine acyltransferase (LPCAT) and among the four LPCAT members in human, the LPCAT3 preferentially introduces polyunsaturated acyl onto the sn-2 position of lysophosphatidylcholine, thereby modulating the membrane fluidity and membrane protein functions therein. Combining the x-ray crystallography and the cryo-electron microscopy, we determined the structures of LPCAT3 in apo-, acyl donor-bound, and acyl receptor-bound states. A reaction chamber was revealed in the LPCAT3 structure where the lysophosphatidylcholine and arachidonoyl-CoA were positioned in two tunnels connected near to the catalytic center. A side pocket was found expanding the tunnel for the arachidonoyl CoA and holding the main body of arachidonoyl. The structural and functional analysis provides the basis for the re-acylation of lysophosphatidylcholine and the substrate preference during the reactions.
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1-Acilglicerofosfocolina O-Aciltransferase/química , Fosfolipídeos/química , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Acil Coenzima A/química , Acil Coenzima A/metabolismo , Acilação , Animais , Domínio Catalítico , Galinhas , Microscopia Crioeletrônica , Cristalografia por Raios X , Lisofosfatidilcolinas/química , Lisofosfatidilcolinas/metabolismo , Modelos Moleculares , Fosfolipídeos/metabolismo , Multimerização Proteica , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
Resource recovery from piggery biogas slurry has become an inevitable demand for sustainable development of pig industry. Microalgae show great potential in recovering nitrogen and phosphorus from piggery slurry, but struggle to utilize organic pollutants, as most of them are inert components (e.g., humic acids, HAs). In this study, nano-TiO2 was used to enhance the utilization of HAs by microalgae from piggery biogas slurry. Results showed that the optimal conditions for microalgal growth and HAs removal by the microalgae-TiO2 coupling system were TiO2 dosage of 0.30 g/L, microalgal inoculation concentration of 0.40 g/L, light intensity of 360 µmol photon/(m2·s) and temperature of 30 °C, with the microalgal chlorophyll concentration of 6.51 mg/L and HAs removal efficiency of 50.14%. Analysis of HAs composition variations in the piggery biogas slurry indicated that the decrease of HAs was caused by their decomposition into small molecules under the photocatalytic reactions of TiO2.