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1.
Neural Regen Res ; 20(1): 6-20, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38767472

RESUMO

The endoplasmic reticulum, a key cellular organelle, regulates a wide variety of cellular activities. Endoplasmic reticulum autophagy, one of the quality control systems of the endoplasmic reticulum, plays a pivotal role in maintaining endoplasmic reticulum homeostasis by controlling endoplasmic reticulum turnover, remodeling, and proteostasis. In this review, we briefly describe the endoplasmic reticulum quality control system, and subsequently focus on the role of endoplasmic reticulum autophagy, emphasizing the spatial and temporal mechanisms underlying the regulation of endoplasmic reticulum autophagy according to cellular requirements. We also summarize the evidence relating to how defective or abnormal endoplasmic reticulum autophagy contributes to the pathogenesis of neurodegenerative diseases. In summary, this review highlights the mechanisms associated with the regulation of endoplasmic reticulum autophagy and how they influence the pathophysiology of degenerative nerve disorders. This review would help researchers to understand the roles and regulatory mechanisms of endoplasmic reticulum-phagy in neurodegenerative disorders.

2.
Cell Signal ; : 111298, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39004325

RESUMO

Circular RNAs (circRNAs) are covalently closed, single-stranded RNAs that play critical roles in various biological processes and diseases, including cancers. However, the functions and mechanisms of circRNAs in hepatocellular carcinoma (HCC) need further clarification. Here, we identified and confirmed that circATF6 is downregulated in HCC tissues and negatively associated with the overall survival of HCC patients. Ectopic overexpression of circATF6 inhibits malignant phenotypes of HCC cells in vitro and in vivo, while knockdown of circATF6 had opposite effects. Mechanistically, we found that circATF6 bound to calreticulin (CALR) protein and acted as a scaffold to enhance the interaction of CALR with calpain2 (CAPN2), which promoted the degradation of CALR by its enzymatic activity. Moreover, we found that circATF6 inhibited HCC cells by suppressing CALR-mediated wnt/ß-catenin signaling pathway. Taken together, our findings suggest that circATF6 is a potential prognostic biomarker and therapeutic target for HCC.

3.
Adv Sci (Weinh) ; : e2404433, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39005186

RESUMO

Growing demand for wound care resulting from the increasing chronic diseases and trauma brings intense pressure to global medical health service system. Artificial skin provides mechanical and microenvironmental support for wound, which is crucial in wound healing and tissue regeneration. However, challenges still remain in the clinical application of artificial skin since the lack of the synergy effect of necessary performance. In this study, a multi-functional artificial skin is fabricated through microfluidic spinning technology by using core-shell gel nanofiber scaffolds (NFSs). This strategy can precisely manipulate the microstructure of artificial skin under microscale. The as-prepared artificial skin demonstrates superior characteristics including surface wettability, breathability, high mechanical strength, strain sensitivity, biocompatibility and biodegradability. Notably, this artificial skin has the capability to deliver medications in a controlled and sustained manner, thereby accelerating the wound healing process. This innovative approach paves the way for the development of a new generation of artificial skin and introduces a novel concept for the structural design of the unique core-shell gel NFSs.

4.
Front Immunol ; 15: 1405146, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38947338

RESUMO

Background: Patients with resectable esophageal squamous cell carcinoma (ESCC) receiving neoadjuvant immunotherapy (NIT) display variable treatment responses. The purpose of this study is to establish and validate a radiomics based on enhanced computed tomography (CT) and combined with clinical data to predict the major pathological response to NIT in ESCC patients. Methods: This retrospective study included 82 ESCC patients who were randomly divided into the training group (n = 57) and the validation group (n = 25). Radiomic features were derived from the tumor region in enhanced CT images obtained before treatment. After feature reduction and screening, radiomics was established. Logistic regression analysis was conducted to select clinical variables. The predictive model integrating radiomics and clinical data was constructed and presented as a nomogram. Area under curve (AUC) was applied to evaluate the predictive ability of the models, and decision curve analysis (DCA) and calibration curves were performed to test the application of the models. Results: One clinical data (radiotherapy) and 10 radiomic features were identified and applied for the predictive model. The radiomics integrated with clinical data could achieve excellent predictive performance, with AUC values of 0.93 (95% CI 0.87-0.99) and 0.85 (95% CI 0.69-1.00) in the training group and the validation group, respectively. DCA and calibration curves demonstrated a good clinical feasibility and utility of this model. Conclusion: Enhanced CT image-based radiomics could predict the response of ESCC patients to NIT with high accuracy and robustness. The developed predictive model offers a valuable tool for assessing treatment efficacy prior to initiating therapy, thus providing individualized treatment regimens for patients.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Imunoterapia , Aprendizado de Máquina , Terapia Neoadjuvante , Tomografia Computadorizada por Raios X , Humanos , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Masculino , Feminino , Terapia Neoadjuvante/métodos , Tomografia Computadorizada por Raios X/métodos , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Imunoterapia/métodos , Nomogramas , Resultado do Tratamento , Adulto , Radiômica
5.
mLife ; 3(2): 240-250, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38948148

RESUMO

Cytidine triphosphate synthase (CTPS) plays a pivotal role in the de novo synthesis of cytidine triphosphate (CTP), a fundamental building block for RNA and DNA that is essential for life. CTPS is capable of directly binding to all four nucleotide triphosphates: adenine triphosphate, uridine triphosphate, CTP, and guanidine triphosphate. Furthermore, CTPS can form cytoophidia in vivo and metabolic filaments in vitro, undergoing regulation at multiple levels. CTPS is considered a potential therapeutic target for combating invasions or infections by viral or prokaryotic pathogens. Utilizing cryo-electron microscopy, we determined the structure of Escherichia coli CTPS (ecCTPS) filament in complex with CTP, nicotinamide adenine dinucleotide (NADH), and the covalent inhibitor 6-diazo-5-oxo- l-norleucine (DON), achieving a resolution of 2.9 Å. We constructed a phylogenetic tree based on differences in filament-forming interfaces and designed a variant to validate our hypothesis, providing an evolutionary perspective on CTPS filament formation. Our computational analysis revealed a solvent-accessible ammonia tunnel upon DON binding. Through comparative structural analysis, we discern a distinct mode of CTP binding of ecCTPS that differs from eukaryotic counterparts. Combining biochemical assays and structural analysis, we determined and validated the synergistic inhibitory effects of CTP with NADH or adenine on CTPS. Our results expand our comprehension of the diverse regulatory aspects of CTPS and lay a foundation for the design of specific inhibitors targeting prokaryotic CTPS.

6.
Plant J ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985498

RESUMO

ERFs (ethylene-responsive factors) are known to play a key role in orchestrating cold stress signal transduction. However, the regulatory mechanisms and target genes of most ERFs are far from being well deciphered. In this study, we identified a cold-induced ERF, designated as PtrERF110, from trifoliate orange (Poncirus trifoliata L. Raf., also known as Citrus trifoliata L.), an elite cold-hardy plant. PtrERF110 is a nuclear protein with transcriptional activation activity. Overexpression of PtrERF110 remarkably enhanced cold tolerance in lemon (Citrus limon) and tobacco (Nicotiana tabacum), whereas VIGS (virus-induced gene silencing)-mediated knockdown of PtrERF110 drastically impaired the cold tolerance. RNA sequence analysis revealed that PtrERF110 overexpression resulted in global transcriptional reprogramming of a range of stress-responsive genes. Three of the genes, including PtrERD6L16 (early responsive dehydration 6-like transporters), PtrSPS4 (sucrose phosphate synthase 4), and PtrUGT80B1 (UDP-glucose: sterol glycosyltransferases 80B1), were confirmed as direct targets of PtrERF110. Consistently, PtrERF110-overexpressing plants exhibited higher levels of sugars and sterols compared to their wild type counterparts, whereas the VIGS plants had an opposite trend. Exogenous supply of sucrose restored the cold tolerance of PtrERF110-silencing plants. In addition, knockdown of PtrSPS4, PtrERD6L16, and PtrUGT80B1 substantially impaired the cold tolerance of P. trifoliata. Taken together, our findings indicate that PtrERF110 positively modulates cold tolerance by directly regulating sugar and sterol synthesis through transcriptionally activating PtrERD6L16, PtrSPS4, and PtrUGT80B1. The regulatory modules (ERF110-ERD6L16/SPS4/UGT80B1) unraveled in this study advance our understanding of the molecular mechanisms underlying sugar and sterol accumulation in plants subjected to cold stress.

7.
Biomed Environ Sci ; 37(6): 639-646, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38988114

RESUMO

Objective: To develop a highly sensitive and rapid nucleic acid detection method for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods: We designed, developed, and manufactured an integrated disposable device for SARS-CoV-2 nucleic acid extraction and detection. The precision of the liquid transfer and temperature control was tested. A comparison between our device and a commercial kit for SARS-Cov-2 nucleic acid extraction was performed using real-time fluorescence reverse transcription polymerase chain reaction (RT-PCR). The entire process, from SARS-CoV-2 nucleic acid extraction to amplification, was evaluated. Results: The precision of the syringe transfer volume was 19.2 ± 1.9 µL (set value was 20), 32.2 ± 1.6 (set value was 30), and 57.2 ± 3.5 (set value was 60). Temperature control in the amplification tube was measured at 60.0 ± 0.0 °C (set value was 60) and 95.1 ± 0.2 °C (set value was 95) respectively. SARS-Cov-2 nucleic acid extraction yield through the device was 7.10 × 10 6 copies/mL, while a commercial kit yielded 2.98 × 10 6 copies/mL. The mean time to complete the entire assay, from SARS-CoV-2 nucleic acid extraction to amplification detection, was 36 min and 45 s. The detection limit for SARS-CoV-2 nucleic acid was 250 copies/mL. Conclusion: The integrated disposable devices may be used for SARS-CoV-2 Point-of-Care test (POCT).


Assuntos
COVID-19 , Equipamentos Descartáveis , RNA Viral , SARS-CoV-2 , SARS-CoV-2/isolamento & purificação , COVID-19/diagnóstico , COVID-19/virologia , Humanos , RNA Viral/isolamento & purificação , RNA Viral/análise , Teste de Ácido Nucleico para COVID-19/instrumentação , Teste de Ácido Nucleico para COVID-19/métodos , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/instrumentação
8.
Mar Genomics ; 76: 101126, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39009497

RESUMO

Isolated from intertidal sediment of the Yellow Sea, China, Bremerella sp. P1 putatively represents a novel species within the genus Bremerella of the family Pirellulaceae in the phylum Planctomycetota. The complete genome of strain P1 comprises a single circular chromosome with a size of 6,955,728 bp and a GC content of 55.26%. The genome contains 5772 protein-coding genes, 80 tRNA and 6 rRNA genes. A total of 147 CAZymes and 128 sulfatases have been identified from the genome of strain P1, indicating that the strain has the capability to degrade a wide range of polysaccharides. Moreover, a gene cluster related to bacterial microcompartments (BMCs) formation containing genes encoding the shell proteins and related enzymes to metabolize fucose or rhamnose is also found in the genome of strain P1. The genome of strain P1 represents the second complete one in the genus Bremerella, expanding the understanding of the physiological and metabolic characteristics, interspecies diversity, and ecological functions of the genus.


Assuntos
Genoma Bacteriano , Polissacarídeos , Polissacarídeos/metabolismo , Sequenciamento Completo do Genoma , China
9.
Sci Rep ; 14(1): 15246, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956068

RESUMO

This study aimed to explore the effects of peroxisome proliferator-activated receptor α (PPAR-α), a known inhibitor of ferroptosis, in Myocardial ischemia/reperfusion injury (MIRI) and its related mechanisms. In vivo and in vitro MIRI models were established. Our results showed that activation of PPAR-α decreased the size of the myocardial infarct, maintained cardiac function, and decreased the serum contents of creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and Fe2+ in ischemia/reperfusion (I/R)-treated mice. Additionally, the results of H&E staining, DHE staining, TUNEL staining, and transmission electron microscopy demonstrated that activation of PPAR-α inhibited MIRI-induced heart tissue and mitochondrial damage. It was also found that activation of PPAR-α attenuated MIRI-induced ferroptosis as shown by a reduction in malondialdehyde, total iron, and reactive oxygen species (ROS). In vitro experiments showed that intracellular contents of malondialdehyde, total iron, LDH, reactive oxygen species (ROS), lipid ROS, oxidized glutathione disulphide (GSSG), and Fe2+ were reduced by the activation of PPAR-α in H9c2 cells treated with anoxia/reoxygenation (A/R), while the cell viability and GSH were increased after PPAR-α activation. Additionally, changes in protein levels of the ferroptosis marker further confirmed the beneficial effects of PPAR-α activation on MIRI-induced ferroptosis. Moreover, the results of immunofluorescence and dual-luciferase reporter assay revealed that PPAR-α achieved its activity via binding to the 14-3-3η promoter, promoting its expression level. Moreover, the cardioprotective effects of PPAR-α could be canceled by pAd/14-3-3η-shRNA or Compound C11 (14-3-3η inhibitor). In conclusion, our results indicated that ferroptosis plays a key role in aggravating MIRI, and PPAR-α/14-3-3η pathway-mediated ferroptosis and mitochondrial injury might be an effective therapeutic target against MIRI.


Assuntos
Proteínas 14-3-3 , Ferroptose , Traumatismo por Reperfusão Miocárdica , PPAR alfa , Ferroptose/efeitos dos fármacos , Animais , PPAR alfa/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Proteínas 14-3-3/metabolismo , Camundongos , Masculino , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Linhagem Celular , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Camundongos Endogâmicos C57BL , Ratos , Modelos Animais de Doenças
10.
Ultrasound Q ; 40(3)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38958999

RESUMO

ABSTRACT: The objective of the study was to use a deep learning model to differentiate between benign and malignant sentinel lymph nodes (SLNs) in patients with breast cancer compared to radiologists' assessments.Seventy-nine women with breast cancer were enrolled and underwent lymphosonography and contrast-enhanced ultrasound (CEUS) examination after subcutaneous injection of ultrasound contrast agent around their tumor to identify SLNs. Google AutoML was used to develop image classification model. Grayscale and CEUS images acquired during the ultrasound examination were uploaded with a data distribution of 80% for training/20% for testing. The performance metric used was area under precision/recall curve (AuPRC). In addition, 3 radiologists assessed SLNs as normal or abnormal based on a clinical established classification. Two-hundred seventeen SLNs were divided in 2 for model development; model 1 included all SLNs and model 2 had an equal number of benign and malignant SLNs. Validation results model 1 AuPRC 0.84 (grayscale)/0.91 (CEUS) and model 2 AuPRC 0.91 (grayscale)/0.87 (CEUS). The comparison between artificial intelligence (AI) and readers' showed statistical significant differences between all models and ultrasound modes; model 1 grayscale AI versus readers, P = 0.047, and model 1 CEUS AI versus readers, P < 0.001. Model 2 r grayscale AI versus readers, P = 0.032, and model 2 CEUS AI versus readers, P = 0.041.The interreader agreement overall result showed κ values of 0.20 for grayscale and 0.17 for CEUS.In conclusion, AutoML showed improved diagnostic performance in balance volume datasets. Radiologist performance was not influenced by the dataset's distribution.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Linfonodo Sentinela , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Linfonodo Sentinela/diagnóstico por imagem , Pessoa de Meia-Idade , Idoso , Adulto , Radiologistas/estatística & dados numéricos , Ultrassonografia Mamária/métodos , Meios de Contraste , Metástase Linfática/diagnóstico por imagem , Ultrassonografia/métodos , Biópsia de Linfonodo Sentinela/métodos , Mama/diagnóstico por imagem , Reprodutibilidade dos Testes
11.
MedComm (2020) ; 5(7): e623, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38988495

RESUMO

This study aimed to identify the role of chromothripsis as a novel biomarker in the prognosis and differentiation diagnosis of pancreatic neuroendocrine neoplasms (pNENs). We conducted next-generation gene sequencing in a cohort of 30 patients with high-grade (G3) pNENs. As a reference, a similar analysis was also performed on 25 patients with low-grade (G1/G2) pancreatic neuroendocrine tumors (pNETs). Chromothripsis and its relationship with clinicopathological features and prognosis were investigated. The results showed that DNA damage response and repair gene alteration and TP53 mutation were found in 29 and 11 patients, respectively. A total of 14 out of 55 patients had chromothripsis involving different chromosomes. Chromothripsis had a close relationship with TP53 alteration and higher grade. In the entire cohort, chromothripsis was associated with a higher risk of distant metastasis; both chromothripsis and metastasis (ENETS Stage IV) suggested a significantly shorter overall survival (OS). Importantly, in the high-grade pNENs group, chromothripsis was the only independent prognostic indicator significantly associated with a shorter OS, other than TP53 alteration or pathological pancreatic neuroendocrine carcinomas (pNECs) diagnosis. Chromothripsis can guide worse prognosis in pNENs, and help differentiate pNECs from high-grade (G3) pNETs.

12.
Front Immunol ; 15: 1349033, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38989283

RESUMO

Background: Extramammary Paget's disease (EMPD) is a rare epithelial malignancy, and approximately 30%-40% of EMPD patients overexpress human epidermal growth factor receptor 2 (Her-2). Currently, there are no established standard treatments for advanced EMPD while anti-Her-2 therapy is recommended for Her-2-positive cases. Case presentation: Here, we report a 51-year-old male diagnosed with advanced Her-2-positive EMPD, presenting with numerous lymph node metastases. This patient received disitamab vedotin (an antibody-drug conjugate, targeting Her-2) combined with serplulimab as first-line treatment. After seven cycles of combination therapy, the patient tolerated the treatment well and the lymph node lesions continued to shrink. However, the patient developed immunotherapy-related pneumonia following the eighth treatment. Hormone therapy was administered while all the anti-tumor therapies were halted. After the pneumonia improved, the patient underwent positron emission tomography-computed tomography, revealing a complete response to his tumor. To consolidate the effect, he received another five cycles of disitamab vedotin monotherapy as maintenance therapy, without experiencing any adverse events. To date, the patient has remained in good health without any recurrence 10 months after drug discontinuance. Conclusion: Disitamab vedotin combined with immunotherapy demonstrated a long-term clinical benefit in advanced Her-2-positive EMPD. For rare solid tumors with Her-2 overexpression, disitamab vedotin combined with immunotherapy might offer a viable therapeutic choice.


Assuntos
Doença de Paget Extramamária , Receptor ErbB-2 , Humanos , Masculino , Pessoa de Meia-Idade , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Doença de Paget Extramamária/tratamento farmacológico , Doença de Paget Extramamária/terapia , Escroto/patologia , Resultado do Tratamento , Imunoterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Imunoconjugados/uso terapêutico
13.
J Neurosci Methods ; 409: 110212, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960331

RESUMO

BACKGROUND: The forced swim test (FST) and tail suspension test (TST) are widely used to assess depressive-like behaviors in animals. Immobility time is used as an important parameter in both FST and TST. Traditional methods for analyzing FST and TST rely on manually setting the threshold for immobility, which is time-consuming and subjective. NEW METHOD: We proposed a threshold-free method for automated analysis of mice in these tests using a Dual-Stream Activity Analysis Network (DSAAN). Specifically, this network extracted spatial information of mice using a limited number of video frames and combined it with temporal information extracted from differential feature maps to determine the mouse's state. To do so, we developed the Mouse FSTST dataset, which consisted of annotated video recordings of FST and TST. RESULTS: By using DSAAN methods, we identify immobility states at accuracies of 92.51 % and 88.70 % for the TST and FST, respectively. The predicted immobility time from DSAAN is nicely correlated with a manual score, which indicates the reliability of the proposed method. Importantly, the DSAAN achieved over 80 % accuracy for both FST and TST by utilizing only 94 annotated images, suggesting that even a very limited training dataset can yield good performance in our model. COMPARISON WITH EXISTING METHOD(S): Compared with DBscorer and EthoVision XT, our method exhibits the highest Pearson correlation coefficient with manual annotation results on the Mouse FSTST dataset. CONCLUSIONS: We established a powerful tool for analyzing depressive-like behavior independent of threshold, which is capable of freeing users from time-consuming manual analysis.

14.
Heliyon ; 10(12): e32621, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975179

RESUMO

Background: The exosome is a critical component of the intercellular communication., playing a vital role in regulating cell function. These small vesicles contain proteins, mRNAs, miRNAs, and lncRNAs, surrounded by lipid bilayer substances. Most cells in the human body can produce exosomes, released into various body fluids such as urine, blood, and cerebrospinal fluid. Bladder cancer is the most common tumor in the urinary system, with high recurrence and metastasis rates. Early diagnosis and treatment are crucial for improving patient outcomes. Methods: This study employed the PubMed search engine to retrieve publicly accessible data pertaining to urinary exosomes. Results: We summarize the origins and intricate biological characteristics of urinary exosomes, the introduction of research methodologies used in basic experiments to isolate and analyze these exosomes, the discussion of their applications and progress in the diagnosis and treatment of bladder cancer, and the exploration of the current limitations associated with using urinary exosomes as molecular biomarkers for diagnosing bladder cancer. Conclusion: Exosomes isolated from urine may be used as molecular biomarkers for early detection of bladder cancer.

15.
Nat Microbiol ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862603

RESUMO

Dimethylsulfoniopropionate (DMSP) is an abundant marine organosulfur compound with roles in stress protection, chemotaxis, nutrient and sulfur cycling and climate regulation. Here we report the discovery of a bifunctional DMSP biosynthesis enzyme, DsyGD, in the transamination pathway of the rhizobacterium Gynuella sunshinyii and some filamentous cyanobacteria not previously known to produce DMSP. DsyGD produces DMSP through its N-terminal DsyG methylthiohydroxybutyrate S-methyltransferase and C-terminal DsyD dimethylsulfoniohydroxybutyrate decarboxylase domains. Phylogenetically distinct DsyG-like proteins, termed DSYE, with methylthiohydroxybutyrate S-methyltransferase activity were found in diverse and environmentally abundant algae, comprising a mix of low, high and previously unknown DMSP producers. Algae containing DSYE, particularly bloom-forming Pelagophyceae species, were globally more abundant DMSP producers than those with previously described DMSP synthesis genes. This work greatly increases the number and diversity of predicted DMSP-producing organisms and highlights the importance of Pelagophyceae and other DSYE-containing algae in global DMSP production and sulfur cycling.

16.
J Am Chem Soc ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859580

RESUMO

In the realm of organic synthesis, the catalytic and stereoselective formation of C-glycosidic bonds is a pivotal process, bridging carbohydrates with aglycones. However, the inherent chirality of the saccharide scaffold often has a substantial impact on the stereoinduction imposed by a chiral ligand. In this study, we have established an unprecedented zirconaaziridine-mediated asymmetric nickel catalysis, enabling the diastereoselective coupling of bench-stable glycosyl phosphates with a range of (hetero)aromatic and glycal iodides as feasible coupling electrophiles. Our developed method showcases a broad scope and a high tolerance for various functional groups. More importantly, precise stereocontrol toward both anomeric configurations of forming C(sp2)-glycosides can be realized by simply utilizing the popular chiral bioxazoline (biOx) ligands in this reductive Ni catalysis. Regarding the operating mechanism, both experimental and computational studies support the occurrence of a redox transmetalation process, leading to the formation of a transient, bimetallic Ni-Zr species that acts as a potent and efficient single-electron reductant in the catalytic process.

18.
J Intell ; 12(6)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38921694

RESUMO

Curiosity is one of the most fundamental biological drives that stimulates individuals' intense desire to explore, learn, and create. Yet, mechanisms of how curiosity is influenced by instructional pedagogy remain unclear. To shed light on this gap, the present study sets out to investigate the underlying channels linking active learning pedagogy, learner engagement, and learner curiosity, employing a partial least-squares structural equation model leveraging the Social and Emotional Skills Survey dataset across ten sites (N = 45,972). Findings indicate that active learning pedagogy is positively associated with learner engagement (std. ß = 0.016, p = 0.005), but there lacks a significant direct effect on learner curiosity (std. ß = -0.001, p = 0.738). Structural mediation results show that learner engagement is a key mediating channel linking active learning pedagogy and learner curiosity (std. ß = 0.013, p = 0.005).

19.
Adv Mater ; : e2405641, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877353

RESUMO

Osteoarthritis (OA) is a prevalent disease, characterized by subchondral fractures in its initial stages, which has no precise and specific treatment now. Here, a novel multifunctional scaffold is synthesized by photopolymerizing glycidyl methacrylate-modified hyaluronic acid (GMHA) as the matrix in the presence of hollow porous magnetic microspheres based on hydroxyapatite. In vivo subchondral bone repairing results demonstrate that the scaffold's meticulous design has most suitable properties for subchondral bone repair. The porous structure of inorganic particles within the scaffold facilitates efficient transport of loaded exogenous vascular endothelial growth factor (VEGF). The Fe3O4 nanoparticles assembled in microspheres promote the osteogenic differentiation of bone marrow mesenchymal stem cells and accelerate the new bone generation. These features enable the scaffold to exhibit favorable subchondral bone repair properties and attain high cartilage repair scores. The therapy results prove that the subchondral bone support considerably influences the upper cartilage repair process. Furthermore, magnetic resonance imaging monitoring demonstrates that Fe3O4 nanoparticles, which are gradually replaced by new bone during osteochondral defect repair, allow a noninvasive and radiation-free assessment to track the newborn bone during the OA repair process. The composite hydrogel scaffold (CHS) provides a versatile platform for biomedical applications in OA treatment.

20.
Yi Chuan ; 46(6): 478-489, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38886151

RESUMO

Metronidazole (MTZ), a commonly used anti-infective drug in clinical practice, has also been employed as a prodrug in cell-targeted ablation systems in scientific research, exhibiting significant application value. However, it has been demonstrated that MTZ can induce neurotoxic symptoms to some extent during its use, and there is currently a lack of effective means to circumvent its toxicity in both clinical and research settings, which limits its application. Therefore, exploring the specific mechanisms underlying MTZ-induced neurotoxic symptoms and elucidating countermeasures will enhance the practical value of MTZ. In this study, using a zebrafish spinal cord injury regeneration model, we confirmed that MTZ neurotoxicity leads to impaired axon regeneration in the central nervous system. By overexpressing il34 in the central nervous system of zebrafish, we eliminated the inhibitory effect of MTZ on axonal regeneration and demonstrated that the pro-regenerative effect against MTZ neurotoxicity is not caused by excessive macrophages/microglia chemoattracted by interleukin 34(Il34). Transcriptome sequencing analysis and GO enrichment analysis of differentially expressed genes between groups revealed that Il34 may counteract MTZ neurotoxicity and promote spinal cord injury repair through biological processes that enhance cellular adhesion and cell location. In summary, our work uncovers a possible cause of MTZ neurotoxicity and provides a new perspective for eliminating MTZ toxicity.


Assuntos
Metronidazol , Traumatismos da Medula Espinal , Regeneração da Medula Espinal , Peixe-Zebra , Animais , Metronidazol/farmacologia , Metronidazol/efeitos adversos , Regeneração da Medula Espinal/efeitos dos fármacos , Traumatismos da Medula Espinal/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo
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