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1.
Molecules ; 28(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37687022

RESUMO

Natural products play a key role in innovative drug discovery. To explore the potential application of natural products and their analogues in pharmacology, total synthesis is a key tool that provides natural product candidates and synthetic analogues for drug development and potential clinical trials. Deconstructive synthesis, namely building new, challenging structures through bond cleavage of easily accessible moieties, has emerged as a useful design principle in synthesizing bioactive natural products. Divergent synthesis, namely synthesizing many natural products from a common intermediate, can improve the efficiency of chemical synthesis and generate libraries of molecules with unprecedented structural diversity. In this review, we will firstly introduce five recent and excellent examples of deconstructive and divergent syntheses of natural products (2021-2023). Then, we will summarize our previous work on the deconstructive and divergent synthesis of natural products to demonstrate the high efficiency and simplicity of these two strategies in the field of total synthesis.


Assuntos
Produtos Biológicos , Desenvolvimento de Medicamentos , Descoberta de Drogas
2.
J Am Chem Soc ; 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37605370

RESUMO

The first total syntheses of polycyclic diterpenes phomopsene (1), methyl phomopsenonate (2), and iso-phomopsene (3) have been accomplished through the unusual cascade reorganization of C-C single bonds. This approach features: (i) a synergistic Nazarov cyclization/double ring expansions in one-step, developed by authors, to rapid and stereospecific construction of the 5/5/5/5 tetraquinane scaffold bearing contiguous quaternary centers and (ii) a one-pot strategic ring expansion through Beckmann fragmentation/recombination to efficiently assemble the requisite 5/5/6/5 tetracyclic skeleton of the target molecules 1-3. This work enables us to determine that the correct structure of iso-phomopsene is, in fact, the C7 epimer of the originally assigned structure. Finally, the absolute configurations of three target molecules were confirmed through enantioselective synthesis.

3.
Nat Commun ; 14(1): 5242, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37640697

RESUMO

Osteoarthritis is a prevalent age-related disease characterized by dysregulation of extracellular matrix metabolism, lipid metabolism, and upregulation of senescence-associated secretory phenotypes. Herein, we clarify that CircRREB1 is highly expressed in secondary generation chondrocytes and its deficiency can alleviate FASN related senescent phenotypes and osteoarthritis progression. CircRREB1 impedes proteasome-mediated degradation of FASN by inhibiting acetylation-mediated ubiquitination. Meanwhile, CircRREB1 induces RanBP2-mediated SUMOylation of FASN and enhances its protein stability. CircRREB1-FASN axis inhibits FGF18 and FGFR3 mediated PI3K-AKT signal transduction, then increased p21 expression. Intra-articular injection of adenovirus-CircRreb1 reverses the protective effects in CircRreb1 deficiency mice. Further therapeutic interventions could have beneficial effects in identifying CircRREB1 as a potential prognostic and therapeutic target for age-related OA.


Assuntos
Metabolismo dos Lipídeos , Osteoartrite , Animais , Camundongos , Condrócitos , Fosfatidilinositol 3-Quinases/genética , Processamento de Proteína Pós-Traducional , Fenótipo
4.
J Exp Bot ; 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37610886

RESUMO

It is often expected that Zn decreases Cd accumulation in plants due to competitions for the same transporters. Here, we found that increasing Zn supply markedly increased the root-to-shoot translocation of Cd in rice. RNA sequencing showed that high Zn up-regulated expression of genes involved in glutathione biosynthesis and metabolism and the Zn/Cd transporter gene OsHMA2, but down-regulated expression of genes related to Zn uptake. Knockout of the iron or Zn transporter genes OsIRT1, OsIRT2 or OsZIP9 did not affect the Zn promotional effect on Cd translocation. Knockout of the manganese/Cd transporter gene OsNRAMP5 greatly reduced Cd uptake but did not affect the Zn promotional effect. Variation in the tonoplast transporter gene OsHMA3 affected Cd translocation but did not change the Zn promotional effect. Knockout of the Zn/Cd transporter gene OsHMA2 not only decreased Cd and Zn translocation, but also abolished the Zn promotional effect. Increased expression of OsHMA2 under high Zn condition supports the hypothesis that this transporter participates in the promotional effect of Zn on Cd translocation. Results also show that OsIRT1, OsIRT2 and OsZIP9 made only small contributions to Cd uptake under low Zn condition but not under high Zn condition, whereas the dominant role of OsNRAMP5 in Cd uptake diminished under low Zn condition.

5.
Sheng Wu Gong Cheng Xue Bao ; 39(7): 2743-2761, 2023 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-37584129

RESUMO

Nitrate is the main form of inorganic nitrogen that crop absorbs, and nitrate transporter 2 (NRT2) is a high affinity transporter using nitrate as a specific substrate. When the available nitrate is limited, the high affinity transport systems are activated and play an important role in the process of nitrate absorption and transport. Most NRT2 cannot transport nitrates alone and require the assistance of a helper protein belonging to nitrate assimilation related family (NAR2) to complete the absorption or transport of nitrates. Crop nitrogen utilization efficiency is affected by environmental conditions, and there are differences between varieties, so it is of great significance to develop varieties with high nitrogen utilization efficiency. Sorghum bicolor has high stress tolerance and is more efficient in soil nitrogen uptake and utilization. The S. bicolor genome database was scanned to systematically analyze the gene structure, chromosomal localization, physicochemical properties, secondary structure and transmembrane domain, signal peptide and subcellular localization, promoter region cis-acting elements, phylogenetic evolution, single nucleotide polymorphism (SNP) recognition and annotation, and selection pressure of the gene family members. Through bioinformatics analysis, 5 NRT2 gene members (designated as SbNRT2-1a, SbNRT2-1b, SbNRT2-2, SbNRT2-3, and SbNRT2-4) and 2 NAR2 gene members (designated as SbNRT3-1 and SbNRT3-2) were identified, the number of which was less than that of foxtail millet. SbNRT2/3 were distributed on 3 chromosomes, and could be divided into four subfamilies. The genetic structure of the same subfamilies was highly similar. The average value of SbNRT2/3 hydrophilicity was positive, indicating that they were all hydrophobic proteins, whereas α-helix and random coil accounted for more than 70% of the total secondary structure. Subcellular localization occurred on plasma membrane, where SbNRT2 proteins did not contain signal peptides, but SbNRT3 proteins contained signal peptides. Further analysis revealed that the number of transmembrane domains of the SbNRT2s family members was greater than 10, while that of the SbNRT3s were 2. There was a close collinearity between NRT2/3s of S. bicolor and Zea mays. Protein domains analysis showed the presence of MFS_1 and NAR2 protein domains, which supported executing high affinity nitrate transport. Phylogenetic tree analysis showed that SbNRT2/3 were more closely related to those of Z. mays and Setaria italic. Analysis of gene promoter cis-acting elements indicated that the promoter region of SbNRT2/3 had several plant hormones and stress response elements, which might respond to growth and environmental cues. Gene expression heat map showed that SbNRT2-3 and SbNRT3-1 were induced by nitrate in the root and stem, respectively, and SbNRT2-4 and SbNRT2-3 were induced by low nitrogen in the root and stem. Non-synonymous SNP variants were found in SbNRT2-4 and SbNRT2-1a. Selection pressure analysis showed that the SbNRT2/3 were subject to purification and selection during evolution. The expression of SbNRT2/3 gene and the effect of aphid infection were consistent with the expression analysis results of genes in different tissues, and SbNRT2-1b and SbNRT3-1 were significantly expressed in the roots of aphid lines 5-27sug, and the expression levels of SbNRT2-3, SbNRT2-4 and SbNRT3-2 were significantly reduced in sorghum aphid infested leaves. Overall, genome-wide identification, expression and DNA variation analysis of NRT2/3 gene family of Sorghum bicolor provided a basis for elucidating the high efficiency of sorghum in nitrogen utilization.


Assuntos
Transportadores de Nitrato , Sorghum , Nitratos/metabolismo , Sorghum/genética , Sorghum/metabolismo , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Filogenia , Sinais Direcionadores de Proteínas/genética , Nitrogênio/metabolismo , DNA , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
BMC Pregnancy Childbirth ; 23(1): 569, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550654

RESUMO

BACKGROUND: To develop an ultrasound scoring system for placenta accreta spectrum (PAS), evaluate its diagnostic value, and provide a practical approach to prenatal diagnosis of PAS. METHODS: A total of 532 pregnant women (n = 184 no PAS, n = 120 placenta accreta, n = 189 placenta increta, n = 39 placenta percreta) at high-risk for placenta accreta who delivered in the Third Affiliated Hospital of Zhengzhou University between January 2021 and December 2022 underwent prenatal ultrasound to evaluate placental invasion. An ultrasound scoring system that included placental and cervical morphology and history of cesarean section was created. Each feature was assigned a score of 0 ~ 2, according to severity. Thresholds for the total ultrasound score that discriminated between no PAS, placenta accreta, placenta increta, and placenta percreta were calculated. RESULTS: Univariate and multivariate regression analysis identified seven indicators of PAS that were included in the ultrasound scoring system, including placental location, placental thickness, presence/absence of the retroplacental space, thickness of the retroplacental myometrium, presence/absence of placental lacunae, retroplacental myometrial blood flow and history of cesarean section. Using the final ultrasound scoring system, no PAS is diagnosed at a total score < 5, placenta accreta or placenta increta is diagnosed at a total score 5-10, and placenta percreta is diagnosed at a total score ≥ 10. CONCLUSIONS: This study identified seven indicators of PAS and included them in an ultrasound scoring system that has good diagnostic efficacy and clinical utility. TRIAL REGISTRATION: ChiCTR2300069261 (retrospectively registered on 10/03/2023).


Assuntos
Placenta Acreta , Placenta Prévia , Feminino , Gravidez , Humanos , Placenta Acreta/diagnóstico por imagem , Placenta/diagnóstico por imagem , Cesárea , Ultrassonografia Pré-Natal , Diagnóstico Pré-Natal , Placenta Prévia/diagnóstico por imagem , Estudos Retrospectivos
7.
Artigo em Inglês | MEDLINE | ID: mdl-37548773

RESUMO

PURPOSE: The objective of this study is to examine the risk factors that contribute to the development of liver metastasis (LM) in patients who have suffered radical resection for colorectal cancer (CRC), and to establish a nomogram model that can be used to predict the occurrence of the LM. METHODS: The present study enrolled 1377 patients diagnosed with CRC between January 2010 and July 2021. The datasets were allocated to training (n = 965) and validation (n = 412) sets in a randomly stratified manner. The study utilized univariate and multivariate logistic regression analyses to establish a nomogram for predicting LM in patients with CRC. RESULTS: Multivariate analysis revealed that T stage, N stage, number of harvested lymph nodes (LNH), mismatch repair (MMR) status, neutrophil count, monocyte count, postoperative carcinoembryonic antigen (CEA) levels, postoperative cancer antigen 125 (CA125) levels, and postoperative carbohydrate antigen 19-9 (CA19-9) levels were independent predictive factors for LM after radical resection. These factors were then utilized to construct a comprehensive nomogram for predicting LM. The nomogram demonstrated great discrimination, with an area under the curve (AUC) of 0.782 for the training set and 0.768 for the validation set. Additionally, the nomogram exhibited excellent calibration and significant clinical benefit as confirmed by the calibration curves and the decision curve analysis, respectively. CONCLUSION: This nomogram has the potential to support clinicians in identifying high-risk patients who may develop LM post-surgery. Clinicians can devise personalized treatment and follow-up plans, ultimately leading to an improved prognosis for patients.

8.
J Agric Food Chem ; 71(29): 11150-11157, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37435821

RESUMO

This study aimed to investigate the effect of pre-slaughter transport stress on the protein S-nitrosylation levels of pork during 0, 3, and 6 days of aging. Pigs (N = 16) were randomly selected and divided into two treatments: 3 h transport (transport stress, TS) and 3 h transport followed by 3 h resting (control, CON). Results showed that the TS group at 0 and 3 days presented a higher nitric oxide synthase (NOS) activity and neuronal NOS (nNOS) expression than the CON group (P < 0.05). Additionally, nNOS was not only abundantly localized in the membrane but also observed in small amounts in the cytoplasm. The immunoblot of overall S-nitrosylated protein showed that protein S-nitrosylation levels in the TS group were greater than in the CON group during postmortem aging (P < 0.05). This work can deliver novel insights into the mechanism of meat quality changes in response to pre-slaughter stress.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Suínos , Proteína S , Proteínas , Óxido Nítrico/metabolismo
10.
Zhen Ci Yan Jiu ; 48(7): 650-7, 2023 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-37518958

RESUMO

OBJECTIVE: To observe the effect of heat-tonifying needling on Keap1-Nrf2/ARE/HO-1 signal transduction pathway in knee synovium in rabbits with cold syndrome type rheumatoid arthritis (RA), so as to explore its mechanisms underl-ying improvement of RA. METHODS: New Zealand rabbits were randomly divided into normal control, RA model, uniform reinforcing-reducing acupuncture, twisting reinforcing acupuncture and heat-tonifying acupuncture groups, with 6 rabbits in each group. The cold syndrome type RA model was established by subcutaneous injection of mixture fluid of ovalbumin and Freund's complete adjuvant at the shoulder-back as well as injection of mixture of ovalbumin and normal saline into knee-joint cavity combined with ice-compress freezing. Acupuncture stimulation (uniform reinforcing-reducing, or twisting reinforcing or heat-tonifying) was applied to bilateral "Zusanli"(ST36) for 1 min with the needle retained for 30 min, once a day for 7 consecutive days. The general conditions of rabbits in each group were recorded, the thermal pain threshold (TPT) and perimeter of knee joints was measured. Conditions of the synovium in the knee cavity, hydrops, blood flow signal, articular surface, and related muscles were observed by using a color Doppler ultrasonic diagnostic apparatus, and the blood flow signals inside the synovium (image scores) were divided into 0 (no signals), I (1 or 2 dot-like signal), II (less than half) ad III (more than half). After H.E. staining, the pathological changes (0-3 points) were assessed according to the state of inflammatory cell infiltration, and hyperplasia of synovial matrix and coating cells. The expression levels of Keap1, Nrf2, HO-1 and GSH-PX1 mRNAs in the knee synovium were detected by quantitative real-time PCR, and the expression of knee synovial HO-1 protein was measured by Western blot. RESULTS: In comparison with the normal control group, the model group had a significant increase in the perimeter, pathological score, expression of Nrf2, HO-1 mRNAs and HO-1 protein (P<0.05), and an obvious decrease in the TPT, expression levels of Keap1 and GSH-PX1 mRNAs (P<0.05). Relevant to the model group, all the three acupuncture maneuvers reversed modeling-induced increase of perimeter and pathological score (P<0.05), decrease of TPT and expression of GSH-PX1 mRNA(P<0.05), further down-regulated expression of Keap1 mRNA (P<0.05), further up-regulated the expression of Nrf2, HO-1 mRNAs and HO-1 protein (P<0.05). The heat-reinforcing manipulation was significantly superior to uniform reinforcing-reducing and twirling reinforcing manipulations in up-regulating TPT, and expression of Nrf2 mRNA, GSH-PX1 mRNA, HO-1 mRNA and protein (P<0.05), and in down-regulating pathological score and Keap1 mRNA expression (P<0.05). CONCLUSION: Heat-tonifying, uniform reinforcing-reducing and twirling reinforcing needling manipulations may relieve pain and improve pathological state in RA rabbits, which may be associated with their functions in raising the ability of anti-oxidative stress by regulating Keap1-Nrf2/ARE/ HO-1 signaling pathway, the therapeutic effect of heat-tonifying needling is superior to that of uniform reinforcing-reducing and twirling reinforcing needling.


Assuntos
Terapia por Acupuntura , Artrite Reumatoide , Coelhos , Animais , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Temperatura Alta , Ovalbumina/metabolismo , Artrite Reumatoide/genética , Artrite Reumatoide/terapia , Artrite Reumatoide/metabolismo , Transdução de Sinais , Síndrome , Limiar da Dor , RNA Mensageiro
11.
Biomed Mater ; 18(5)2023 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-37429292

RESUMO

Artificial nerve grafts that support axon growth hold promises in promoting nerve regeneration and function recovery. However, current artificial nerve grafts are insufficient to regenerate axons across long nerve gaps. Specific biochemical and biophysical cues are required to be incorporated to artificial nerve grafts to promote neural cell adhesion and guide neurite outgrowth. Polyvinyl alcohol (PVA) nerve conduits have been clinically approved, but the applicability of PVA nerve conduits is limited to short injuries due to low cell binding. In this study, we explored the incorporation of biochemical cues and topographical cues for promoting neuritogenesis and axon guidance. PVA was conjugated with extracellular matrix proteins and fucoidan, a bioactive sulfated polysaccharide, to improve cell adhesion. Micro-sized topographies, including 1.8 µm convex lenses, 2 µm gratings, and 10 µm gratings were successfully fabricated on PVA by nanofabrication, and the synergistic effects of topography and biochemical molecules on pheochromocytoma 12 (PC12) neuritogenesis and neurite alignment were studied. Conjugated fucoidan promoted the percentage of PC12 with neurite outgrowth from 0% to 2.8% and further increased to 5% by presenting laminin on the surface. Additionally, fucoidan was able to bind nerve growth factor (NGF) on the surface and allow for PC12 to extend neurites in NGF-free media. The incorporation of 2 µm gratings could double the percentage of PC12 with neurite outgrowth and neurite length, and guided the neurites to extend along the grating axis. The work presents a promising strategy to enhance neurite formation and axon guidance, presenting significant value in promoting nerve regeneration.


Assuntos
Neoplasias das Glândulas Suprarrenais , Feocromocitoma , Humanos , Ratos , Animais , Álcool de Polivinil , Feocromocitoma/metabolismo , Axônios , Neuritos/metabolismo , Polissacarídeos , Neoplasias das Glândulas Suprarrenais/metabolismo , Células PC12
12.
Heliyon ; 9(7): e18038, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37483815

RESUMO

Mesenchymal stem cells (MSCs) are becoming more popular in therapy. Therefore, in-depth studies on mesenchymal stem cells in therapy are urgently needed. However, the difficulty in culturing and propagating MSCs in vitro complicates potential studies on MSCs in a murine model. OP9 cells are a stromal cell line from mouse bone marrow, which have similar characteristics and functions to MSCs and can maintain their original characteristics. Because of these properties, OP9 cells have become a suitable substitute for research on MSCs. Previously, we have found that MSCs can cure inflammatory bowel disease in mice. In this study, we aimed to investigate whether OP9 cells can functionally regulate and alleviate inflammatory diseases. We evaluated the therapeutic effect of OP9 cells in the mouse model of inflammatory bowel disease and found OP9 cells were able to ameliorate inflammatory bowel disease. We explored the existence of NLRP3 inflammasome in OP9 cells, and showed better therapeutic effects when the NLRP3 inflammasome was suppressed. Thus, OP9 cell line is similar to MSCs in characteristic and function, and is an ideal substitute for MSCs research. The preliminary exploration of the inflammasome system in OP9 cells lays a theoretical and methodological foundation for further study of MSCs.

13.
Cell Death Dis ; 14(7): 421, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37443302

RESUMO

The secretory properties of cancer-associated fibroblasts (CAFs) play predominant roles in shaping a pro-metastatic tumor microenvironment. The present study demonstrated that SLIT2, an axon guidance protein, produced by CAFs and promoted gastric cancer (GC) metastasis in two gastric cancer cell lines (AGS and MKN45) by binding to roundabout guidance receptor 1 (ROBO1). Mass-spectrometry analysis revealed that ROBO1 could interact with NEK9, a serine/threonine kinase. And their mutual binding activities were further enhanced by SLIT2. Domain analysis revealed the kinase domain of NEK9 was critical in its interaction with the intracellular domain (ICD) of ROBO1, and it also directly phosphorylated tripartite motif containing 28 (TRIM28) and cortactin (CTTN) in AGS and MKN45 cells. TRIM28 function as a transcriptional elongation factor, which directly facilitate CTTN activation. In addition, Bioinformatics analysis and experimental validation identified transcriptional regulation of STAT3 and NF-κB p100 by TRIM28, and a synergetic transcription of CTTN by STAT3 and NF-κB p100 was also observed in AGS and MKN45. Therefore, CAF-derived SLIT2 increased the expression and phosphorylation levels of CTTN, which induced cytoskeletal reorganization and GC cells metastasis. A simultaneous increase in the expression levels of NEK9, TRIM28 and CTTN was found in metastatic GC lesions compared with paired non-cancerous tissues and primary cancer lesions via IHC and Multiplex IHC. The analysis of the data from a cohort of patients with GC revealed that increased levels of NEK9, TRIM28 and CTTN were associated with a decreased overall survival rate. On the whole, these findings revealed the connections of CAFs and cancer cells through SLIT2/ROBO1 and inflammatory signaling, and the key molecules involved in this process may serve as potential biomarkers and therapeutic targets for GC.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , NF-kappa B , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Movimento Celular , Microambiente Tumoral , Quinases Relacionadas a NIMA/genética
14.
Sensors (Basel) ; 23(13)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37448025

RESUMO

Distributed denial-of-service (DDoS) attacks pose a significant cybersecurity threat to software-defined networks (SDNs). This paper proposes a feature-engineering- and machine-learning-based approach to detect DDoS attacks in SDNs. First, the CSE-CIC-IDS2018 dataset was cleaned and normalized, and the optimal feature subset was found using an improved binary grey wolf optimization algorithm. Next, the optimal feature subset was trained and tested in Random Forest (RF), Support Vector Machine (SVM), K-Nearest Neighbor (k-NN), Decision Tree, and XGBoost machine learning algorithms, from which the best classifier was selected for DDoS attack detection and deployed in the SDN controller. The results show that RF performs best when compared across several performance metrics (e.g., accuracy, precision, recall, F1 and AUC values). We also explore the comparison between different models and algorithms. The results show that our proposed method performed the best and can effectively detect and identify DDoS attacks in SDNs, providing a new idea and solution for the security of SDNs.


Assuntos
Algoritmos , Software , Benchmarking , Análise por Conglomerados , Aprendizado de Máquina
15.
Sci Adv ; 9(27): eadf8412, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37418527

RESUMO

State-of-the-art ion-selective membranes with ultrahigh precision are of significance for water desalination and energy conservation, but their development is limited by the lack of understanding of the mechanisms of ion transport at the subnanometer scale. Herein, we investigate transport of three typical anions (F-, Cl-, and Br-) under confinement using in situ liquid time-of-flight secondary ion mass spectrometry in combination with transition-state theory. The operando analysis reveals that dehydration and related ion-pore interactions govern anion-selective transport. For strongly hydrated ions [(H2O)nF- and (H2O)nCl-], dehydration enhances ion effective charge and thus the electrostatic interactions with membrane, observed as an increase in decomposed energy from electrostatics, leading to more hindered transport. Contrarily, weakly hydrated ions [(H2O)nBr-] have greater permeability as they allow an intact hydration structure during transport due to their smaller size and the most right-skewed hydration distribution. Our work demonstrates that precisely regulating ion dehydration to maximize the difference in ion-pore interactions could enable the development of ideal ion-selective membranes.


Assuntos
Desidratação , Água , Humanos , Transporte de Íons , Íons , Ânions/química , Água/química
16.
Plant J ; 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37340958

RESUMO

Nitrogen (N) is a vital major nutrient for rice (Oryza sativa). Rice responds to different applications of N by altering its root morphology, including root elongation. Although ammonium ( NH 4 + $$ {\mathrm{NH}}_4^{+} $$ ) is the primary source of N for rice, NH 4 + $$ {\mathrm{NH}}_4^{+} $$ is toxic to rice roots and inhibits root elongation. However, the precise molecular mechanism that NH 4 + $$ {\mathrm{NH}}_4^{+} $$ -inhibited root elongation of rice is not well understood. Here, we identified a rice T-DNA insert mutant of OsMADS5 with a longer seminal root (SR) under sufficient N conditions. Reverse-transcription quantitative PCR analysis revealed that the expression level of OsMADS5 was increased under NH 4 + $$ {\mathrm{NH}}_4^{+} $$ compared with NO 3 - $$ {\mathrm{NO}}_3^{-} $$ supply. Under NH 4 + $$ {\mathrm{NH}}_4^{+} $$ conditions, knocking out OsMADS5 (cas9) produced a longer SR, phenocopying osmads5, while there was no significant difference in SR length between wild-type and cas9 under NO 3 - $$ {\mathrm{NO}}_3^{-} $$ supply. Moreover, OsMADS5-overexpression plants displayed the opposite SR phenotype. Further study demonstrated that enhancement of OsMADS5 by NH 4 + $$ {\mathrm{NH}}_4^{+} $$ supply inhibited rice SR elongation, likely by reducing root meristem activity of root tip, with the involvement of OsCYCB1;1. We also found that OsMADS5 interacted with OsSPL14 and OsSPL17 (OsSPL14/17) to repress their transcriptional activation by attenuating DNA binding ability. Moreover, loss of OsSPL14/17 function in osmads5 eliminated its stimulative effect on SR elongation under NH 4 + $$ {\mathrm{NH}}_4^{+} $$ conditions, implying OsSPL14/17 may function downstream of OsMADS5 to mediate rice SR elongation under NH 4 + $$ {\mathrm{NH}}_4^{+} $$ supply. Overall, our results indicate the existence of a novel modulatory pathway in which enhancement of OsMADS5 by NH 4 + $$ {\mathrm{NH}}_4^{+} $$ supply represses the transcriptional activities of OsSPL14/17 to restrict SR elongation of rice.

17.
Curr Pharm Des ; 29(19): 1524-1534, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37317923

RESUMO

OBJECTIVE: Ovarian cancer (OC) is the eighth most common cancer with high mortality in women worldwide. Currently, compounds derived from Chinese herbal medicine have provided a new angle for OC treatment. METHODS: In this study, the cell proliferation and migration of ovarian cancer A2780/SKOV3 cells were inhibited after being treated with nitidine chloride (NC) by using MTT and Wound-Healing Assay. Flow cytometry analysis indicated NC-induced apoptosis of ovarian cancer cells, and AO and MDC staining showed that NC treatment induced the appearance of autophagosomes and autophagic lysosomes in ovarian cancer cells. RESULTS: Through the autophagy inhibition experiment of chloroquine, it was proved that NC significantly further promoted apoptosis in ovarian cancer cells. Furthermore, NC proved that it could significantly decrease the expression of autophagy-related genes such as Akt, mTOR, P85 S6K, P70 S6K, and 4E-BP1. CONCLUSION: Therefore, we suggest that NC could trigger autophagy and apoptosis of ovarian cancer cells through Akt/mTOR signaling pathway, and NC may potentially be a target for chemotherapy against ovarian cancer.


Assuntos
Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais , Apoptose , Serina-Treonina Quinases TOR , Autofagia/fisiologia , Proliferação de Células
18.
J Alzheimers Dis ; 94(3): 1121-1132, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37355909

RESUMO

BACKGROUND: The lack of efficient preventive interventions against Alzheimer's disease (AD) calls for identifying efficient modifiable risk factors for AD. As diabetes shares many pathological processes with AD, including accumulation of amyloid plaques and neurofibrillary tangles, insulin resistance, and impaired glucose metabolism, diabetes is thought to be a potentially modifiable risk factor for AD. Mounting evidence suggests that links between AD and diabetes may be more complex than previously believed. OBJECTIVE: To examine the pleiotropic architecture of AD and diabetes mellitus (DM). METHODS: Univariate and pleiotropic analyses were performed following the discovery-replication strategy using individual-level data from 10 large-scale studies. RESULTS: We report a potentially novel pleiotropic NOTCH2 gene, with a minor allele of rs5025718 associated with increased risks of both AD and DM. We confirm previously identified antagonistic associations of the same variants with the risks of AD and DM in the HLA and APOE gene clusters. We show multiple antagonistic associations of the same variants with AD and DM in the HLA cluster, which were not explained by the lead SNP in this cluster. Although the ɛ2 and ɛ4 alleles played a major role in the antagonistic associations with AD and DM in the APOE cluster, we identified non-overlapping SNPs in this cluster, which were adversely and beneficially associated with AD and DM independently of the ɛ2 and ɛ4 alleles. CONCLUSION: This study emphasizes differences and similarities in the heterogeneous genetic architectures of AD and DM, which may differentiate the pathogenic mechanisms of these diseases.


Assuntos
Doença de Alzheimer , Diabetes Mellitus , Resistência à Insulina , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Fatores de Risco , Apolipoproteínas E/genética
19.
Nucleic Acids Res ; 51(12): 5931-5947, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37224527

RESUMO

Many deep learning approaches have been proposed to predict epigenetic profiles, chromatin organization, and transcription activity. While these approaches achieve satisfactory performance in predicting one modality from another, the learned representations are not generalizable across predictive tasks or across cell types. In this paper, we propose a deep learning approach named EPCOT which employs a pre-training and fine-tuning framework, and is able to accurately and comprehensively predict multiple modalities including epigenome, chromatin organization, transcriptome, and enhancer activity for new cell types, by only requiring cell-type specific chromatin accessibility profiles. Many of these predicted modalities, such as Micro-C and ChIA-PET, are quite expensive to get in practice, and the in silico prediction from EPCOT should be quite helpful. Furthermore, this pre-training and fine-tuning framework allows EPCOT to identify generic representations generalizable across different predictive tasks. Interpreting EPCOT models also provides biological insights including mapping between different genomic modalities, identifying TF sequence binding patterns, and analyzing cell-type specific TF impacts on enhancer activity.


Assuntos
Epigenoma , Transcriptoma , Cromatina/genética , Genômica , Genoma
20.
Zhen Ci Yan Jiu ; 48(5): 438-45, 2023 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-37247856

RESUMO

OBJECTIVE: To observe the effect of heat-reinforcing needling (HRN) on inflammatory factors and necrotizing apoptosis of synovial cells in synovial tissues of knee joint in rabbits with cold syndrome rheumatoid arthritis (RA), so as to explore its underlying mechanisms in treating RA. METHODS: By using the random number table method, 40 New Zealand rabbits were randomly divided into normal, model, antagonist(AG), twist-reinforceing needling (TRN) and HRN groups, with 8 rabbits in each group. The model of cold syndrome RA was established by ovalbumin induction combined with Freund's complete adjuvant injection and cryogenic freezing method. In the AG group, the antagonist TAK-632 (25 mg/kg) was administered intragastrically, once every 2 days, for a total of 7 times. Rabbits of TRN and HRN groups were treated with corresponding acupuncture techniques on bilateral "Zusanli" (ST36) for 30 min, once a day for 14 days. After intervention, the changes of knee skin temperature and circumference were measured. Color Doppler ultrasound was used to observe the joint cavity effusion, synovial thickness and internal blood flow signal. The histomorphological changes of synovial tissues were observed after HE staining. ELISA was used to detect the contents of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and IL-6 in serum. Transmission electron microscope was used to observe the ultrastructure, necrosis and apoptosis of synovial cells. Western blot was used to detect the protein expressions of receptor-interacting protein kinase1 (RIPK1), RIPK3, mixed lineage kinase domain-like protein (MLKL), and phosphorylation (p)-MLKL in synovial tissues. RESULTS: Compared with the normal group, the synovial was diffusely hyperplasia, joint cavity effusion and abnormal blood flow signal were obvious, inflammatory cells were clustered, arranged closely and disordered in the model group. The findings of transmission electron microscopy showed disruption of cell membrane integrity, swollen or ruptured mitochondria, obviously ruptured nucleus, condensed and pyknotic chromatin and nucleolus in the model group. Also, the skin temperature of the knee joint was significantly decreased (P<0.01), while the circumference of the knee joint, the contents of TNF-α, IL-1ß and IL-6 in serum, the protein expressions of RIPK1, RIPK3, p-MLKL and MLKL in synovial tissues were significantly increased (P<0.01) in the model group. Compared with the model group, synovial tissue hyperplasia, joint cavity effusion, abnormal blood flow signals, synovial cell proliferation, inflammatory cell infiltration, disruption of cell membrane integrity, cell swelling, cell rupture, and nuclear pyknosis were reduced to different degrees in the AG, TRN and HRN groups. Additionally, the skin temperature of the knee joint was increased (P<0.01, P<0.05), while the circumference of the knee joint, the contents of TNF-α, IL-1ß and IL-6 in serum, the expressions of RIPK1, RIPK3, p-MLKL and MLKL in synovial tissues were decreased (P<0.01, P<0.05) in the AG, TRN and HRN groups. The effects of HRN and AG were notably superior to that of TRN in up-regulating skin temperature of the knee joint, and down-regulating the circumference of the knee joint, the contents of TNF-α, IL-1ß and IL-6 in serum, the expressions of RIPK1, RIPK3, p-MLKL and MLKL in synovial tissues (P<0.01, P<0.05). CONCLUSION: HRN can reduce synovial inflammation of knee joint in rabbits with cold syndrome RA, which may be related to its function in inhibiting the necrotizing apoptosis of synovial cells.


Assuntos
Artrite Reumatoide , Temperatura Alta , Animais , Coelhos , Apoptose , Artrite Reumatoide/genética , Artrite Reumatoide/terapia , Hiperplasia , Inflamação/genética , Inflamação/terapia , Interleucina-6/genética , Articulação do Joelho , Fator de Necrose Tumoral alfa/genética
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