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1.
Animal Model Exp Med ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38962826

RESUMO

BACKGROUND: Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic, while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs. Current knockout strategies are mainly aimed at the genes causing hyperacute immune rejection (HAR) that occurs in the first few hours while adaptive immune reactions orchestrated by CD4 T cell thereafter also cause graft failure, in which process the MHC II molecule plays critical roles. METHODS: Thus, we generate a 4-gene (GGTA1, CMAH, ß4GalNT2, and CIITA) knockout pig by CRISPR/Cas9 and somatic cell nuclear transfer to compromise HAR and CD4 T cell reactions simultaneously. RESULTS: We successfully obtained 4KO piglets with deficiency in all alleles of genes, and at cellular and tissue levels. Additionally, the safety of our animals after gene editing was verified by using whole-genome sequencing and karyotyping. Piglets have survived for more than one year in the barrier, and also survived for more than 3 months in the conventional environment, suggesting that the piglets without MHC II can be raised in the barrier and then gradually mated in the conventional environment. CONCLUSIONS: 4KO piglets have lower immunogenicity, are safe in genomic level, and are easier to breed than the model with both MHC I and II deletion.

2.
Mol Diagn Ther ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967864

RESUMO

BACKGROUND: There is no consensus regarding the specific genes included in the homologous recombination repair (HRR) gene panel for identifying the HRR deficiency (HRD) status and predicting the prognosis of epithelial ovarian cancer (EOC) patients. OBJECTIVE: We aimed to explore a 15-gene panel involving the HRR pathway as a predictive prognostic indicator in Chinese patients newly diagnosed with EOC. PATIENTS AND METHODS: We reviewed the previously published reports about different HRR gene panels and prespecified the 15-gene panel. The genetic testing results in a 15-gene panel from 308 EOC patients diagnosed between 2014 and 2022 from six centers were collected. The association of clinicopathologic characteristics, the use of poly (adenosine diphosphate-ribose) polymerase inhibitors (PARPis) and progression-free survival (PFS) with 15-gene panel HRR mutations (HRRm) status was assessed. RESULTS: 43.2% (133/308) of patients were determined to carry 144 deleterious HRRm, among which 68.1% (98/144) were germline mutations and 32.8% (101/308) were BRCA1/2 gene lethal mutations. The hazard ratio (HR) (95% confidence interval, CI) for PFS (HRRm v HRR wild type, HRRwt) using the 15-gene panel HRRm was 0.42 (0.28-0.64) at all stages and 0.42 (0.27-0.65) at stages IIIC-IV. However, a prognostic difference was observed only between the BRCA mutation group and the HRRwt group, not between the non-BRCA HRRm group and the HRRwt group. For the subgroups of patients not using PARPis, the HR (95% CI) was 0.41 (0.24-0.68) at stages IIIC-IV. CONCLUSIONS: This study provides evidence that 15-gene panel HRRm can predict the prognosis of EOC, of these only the BRCA1/2 mutations, not non-BRCA HRRm, contribute to prognosis prediction. Among patients without PARPis, the HRRm group presented a better PFS. This is the first study of this kind in the Chinese population.

3.
Cell Rep ; 43(7): 114505, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002128

RESUMO

Increasing global concerns about psychoactive substance addiction and psychotic disorders highlight the need for comprehensive research into the structure-function relationship governing ligand recognition between these substances and their receptors in the brain. Recent studies indicate the significant involvement of trace amine-associated receptor 1 (TAAR1) in the signaling regulation of the hallucinogen lysergic acid diethylamide (LSD) and other antipsychotic drugs. This study presents structures of the TAAR1-Gs protein complex recognizing LSD, which exhibits a polypharmacological profile, and the partial agonist RO5263397, which is a drug candidate for schizophrenia and addiction. Moreover, we elucidate the cross-species recognition and partial activation mechanism for TAAR1, which holds promising implications from a drug discovery perspective. Through mutagenesis, functional studies, and molecular dynamics (MD) simulations, we provide a comprehensive understanding of a versatile TAAR1 pocket in recognizing various ligands as well as in the ligand-free state, underpinning the structural basis of its high adaptability. These findings offer valuable insights for the design of antipsychotic drugs.

4.
Toxicon ; 247: 107849, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971474

RESUMO

Mushroom poisoning is a significant contributor to foodborne disease outbreaks in China. This study focuses on two Panaeolus subbalteatus poisoning incidents accompanied by epidemiological investigations, species identification, and toxin detection in Ningxia, northwest China. In these two poisoning incidents, some patients exhibited gastrointestinal or neurological symptoms approximately 0.5 h after ingestion of a large amount of wild mushroom. Specifically, in Case 1, one of the three patients experienced nausea, vomiting, and numbness in the throat and limbs; in Case 2, one patient reported dizziness and an abnormal sense of direction. Through morphological and phylogenetic analyses, mushroom specimens were identified as P. subbalteatus. Psilocybin and psilocin were detected in mushroom samples, and only psilocin was detected in biological samples by liquid chromatography-triple quadrupole-linear ion trap mass spectrometry screening. The average psilocybin and psilocin contents in mushroom samples were 1532.2-1760.7 and 114.5-136.0 mg/kg (n = 3), respectively. Moreover, only psilocin was detected in blood and urine samples, with average concentrations 0.5-1.2 ng/mL (n = 3) and 2.5-3.1 ng/mL (n = 3), respectively. These findings provide technical support for managing similar incidents in the future.

5.
Biomed Eng Online ; 23(1): 69, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39039565

RESUMO

BACKGROUND: Properly understanding the origin and progression of the thoracic aortic aneurysm (TAA) can help prevent its growth and rupture. For a better understanding of this pathogenesis, the aortic blood flow has to be studied and interpreted in great detail. We can obtain detailed aortic blood flow information using magnetic resonance imaging (MRI) based computational fluid dynamics (CFD) with a prescribed motion of the aortic wall. METHODS: We performed two different types of simulations-static (rigid wall) and dynamic (moving wall) for healthy control and a patient with a TAA. For the latter, we have developed a novel morphing approach based on the radial basis function (RBF) interpolation of the segmented 4D-flow MRI geometries at different time instants. Additionally, we have applied reconstructed 4D-flow MRI velocity profiles at the inlet with an automatic registration protocol. RESULTS: The simulated RBF-based movement of the aorta matched well with the original 4D-flow MRI geometries. The wall movement was most dominant in the ascending aorta, accompanied by the highest variation of the blood flow patterns. The resulting data indicated significant differences between the dynamic and static simulations, with a relative difference for the patient of 7.47±14.18% in time-averaged wall shear stress and 15.97±43.32% in the oscillatory shear index (for the whole domain). CONCLUSIONS: In conclusion, the RBF-based morphing approach proved to be numerically accurate and computationally efficient in capturing complex kinematics of the aorta, as validated by 4D-flow MRI. We recommend this approach for future use in MRI-based CFD simulations in broad population studies. Performing these would bring a better understanding of the onset and growth of TAA.


Assuntos
Aorta , Simulação por Computador , Hidrodinâmica , Imageamento por Ressonância Magnética , Humanos , Aorta/diagnóstico por imagem , Aorta/fisiologia , Modelos Cardiovasculares , Hemodinâmica , Velocidade do Fluxo Sanguíneo , Processamento de Imagem Assistida por Computador/métodos , Estresse Mecânico , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/fisiopatologia
6.
J Am Chem Soc ; 146(29): 20045-20058, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39001877

RESUMO

G protein-coupled receptor (GPCR) structural studies with in-solution spectroscopic approaches have offered distinctive insights into GPCR activation and signaling that highly complement those yielded from structural snapshots by crystallography or cryo-EM. While most current spectroscopic approaches allow for probing structural changes at selected residues or loop regions, they are not suitable for capturing a holistic view of GPCR conformational rearrangements across multiple domains. Herein, we develop an approach based on limited proteolysis mass spectrometry (LiP-MS) to simultaneously monitor conformational alterations of a large number of residues spanning both flexible loops and structured transmembrane domains for a given GPCR. To benchmark LiP-MS for GPCR conformational profiling, we studied the adenosine 2A receptor (A2AR) in response to different ligand binding (agonist/antagonist/allosteric modulators) and G protein coupling. Systematic and residue-resolved profiling of A2AR conformational rearrangements by LiP-MS precisely captures structural mechanisms in multiple domains underlying ligand engagement, receptor activation, and allostery, and may also reflect local conformational flexibility. Furthermore, these residue-resolution structural fingerprints of the A2AR protein allow us to readily classify ligands of different pharmacology and distinguish the G protein-coupled state. Thus, our study provides a new structural MS approach that would be generalizable to characterizing conformational transition and plasticity for challenging integral membrane proteins.


Assuntos
Espectrometria de Massas , Conformação Proteica , Receptor A2A de Adenosina , Receptor A2A de Adenosina/química , Receptor A2A de Adenosina/metabolismo , Humanos , Ligantes , Modelos Moleculares , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo
7.
Molecules ; 29(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38999011

RESUMO

Coffee pulp wines were produced through the mixed fermentation of Saccharomyces cerevisiae, and the flavor and sensory characteristics were comparatively evaluated. A total of 87 volatile components were identified from five coffee pulp wines, of which 68 were present in all samples, accounting for over 99% of the total concentration. The sample fermented contained significantly higher levels of volatile metabolites (56.80 mg/g). Alcohols (22 species) and esters (26 species) were the main flavor components, with the contents accounting for 56.45 ± 3.93% and 31.18 ± 4.24%, respectively, of the total. Furthermore, 14 characteristic components were identified as potential odor-active compounds, contributing to sweet and floral apple brandy flavor. Although the characteristic components are similar, the difference in the content makes the overall sensory evaluation of the samples different. The samples formed by fermentation of four strains, which obtained the highest score (86.46 ± 0.36) in sensory evaluation, were further interpreted and demonstrated through the Mantel test. The results of the component analysis were effectively distinguished by OPLS-DA and PCA, and this validation was supported by sensory evaluation. The research results provided a technical reference for the production of coffee pulp wines.


Assuntos
Café , Fermentação , Paladar , Compostos Orgânicos Voláteis , Vinho , Vinho/análise , Café/química , Compostos Orgânicos Voláteis/análise , Aromatizantes/análise , Odorantes/análise , Saccharomyces cerevisiae/metabolismo , Humanos
8.
Mol Cancer ; 23(1): 139, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970106

RESUMO

BACKGROUND: Radioresistance is the leading cause of death in advanced cervical cancer (CC). Dysregulation of RNA modification has recently emerged as a regulatory mechanism in radiation and drug resistance. We aimed to explore the biological function and clinical significance of 5-methylcytosine (m5C) in cervical cancer radiosensitivity. METHODS: The abundance of RNA modification in radiotherapy-resistant and sensitive CC specimens was quantified by liquid chromatography-tandem mass spectrometry. The essential RNA modification-related genes involved in CC radiosensitivity were screened via RNA sequencing. The effect of NSUN6 on radiosensitivity was verified in CC cell lines, cell-derived xenograft (CDX), and 3D bioprinted patient-derived organoid (PDO). The mechanisms of NSUN6 in regulating CC radiosensitivity were investigated by integrative m5C sequencing, mRNA sequencing, and RNA immunoprecipitation. RESULTS: We found a higher abundance of m5C modification in resistant CC samples, and NSUN6 was the essential m5C-regulating gene concerning radiosensitivity. NSUN6 overexpression was clinically correlated with radioresistance and poor prognosis in cervical cancer. Functionally, higher NSUN6 expression was associated with radioresistance in the 3D PDO model of cervical cancer. Moreover, silencing NSUN6 increased CC radiosensitivity in vivo and in vitro. Mechanistically, NDRG1 was one of the downstream target genes of NSUN6 identified by integrated m5C-seq, mRNA-seq, and functional validation. NSUN6 promoted the m5C modification of NDRG1 mRNA, and the m5C reader ALYREF bound explicitly to the m5C-labeled NDRG1 mRNA and enhanced NDRG1 mRNA stability. NDRG1 overexpression promoted homologous recombination-mediated DNA repair, which in turn led to radioresistance in cervical cancer. CONCLUSIONS: Aberrant m5C hypermethylation and NSUN6 overexpression drive resistance to radiotherapy in cervical cancer. Elevated NSUN6 expression promotes radioresistance in cervical cancer by activating the NSUN6/ALYREF-m5C-NDRG1 pathway. The low expression of NSUN6 in cervical cancer indicates sensitivity to radiotherapy and a better prognosis.


Assuntos
5-Metilcitosina , Proteínas de Ciclo Celular , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular , RNA Mensageiro , Tolerância a Radiação , Neoplasias do Colo do Útero , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/patologia , Humanos , Feminino , Tolerância a Radiação/genética , 5-Metilcitosina/metabolismo , 5-Metilcitosina/análogos & derivados , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Animais , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Linhagem Celular Tumoral , Prognóstico , Ensaios Antitumorais Modelo de Xenoenxerto , Metiltransferases/genética , Metiltransferases/metabolismo
9.
Eur J Cardiothorac Surg ; 66(1)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38976648

RESUMO

OBJECTIVES: To investigate the risk factors and prognosis of spinal cord injury (SCI) after surgical procedure in type A aortic dissection (AAD). METHODS: Between January 2013 and December 2021, a total of 1647 patients with AAD underwent surgical procedure. Postoperative SCI occurred in 58 patients, including 24 patients with paraplegia and 34 patients with paraparesis. Factors associated with SCI were identified through comparison between patients with and without SCI. RESULTS: The mean age was 48.8 ± 10.8 years for patients with SCI and 50.1 ± 12.1 years for those without SCI (P = 0.43), with a comparable gender distribution. Median numbers of intercostal and lumbar arteries with involvement were significantly higher in the SCI group (both P < 0.001). The highest (P = 0.033) and lowest (P = 0.001) levels of intraoperative mean arterial pressure (MAP) were significantly lower in the SCI group. Multivariable analysis revealed the number of segmental arteries involved (odds ratio = 1.14, 95% CI 1.08-1.20, P = 0.000), and the duration of hypothermic circulatory arrest (HCA) (odds ratio = 1.04, 95% CI 1.01-1.08, P = 0.042) was positively associated with the occurrence of SCI. Conversely, the lowest level of MAP was negatively associated with SCI (odds ratio = 0.98, 95% CI 0.96-0.99, P = 0.031). During the long-term follow-up, 14 patients with paraplegia needed a wheel chair, while only 1 patient with paraparesis needed one (P < 0.001). CONCLUSIONS: The risk of postoperative SCI increases when AAD patients experience segmental arteries involved, longer HCA duration and decreased intraoperative MAP during operation.


Assuntos
Dissecção Aórtica , Complicações Pós-Operatórias , Traumatismos da Medula Espinal , Humanos , Dissecção Aórtica/cirurgia , Pessoa de Meia-Idade , Masculino , Feminino , Traumatismos da Medula Espinal/complicações , Fatores de Risco , Prognóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Adulto , Aneurisma da Aorta Torácica/cirurgia , Paraplegia/etiologia
10.
Huan Jing Ke Xue ; 45(7): 4006-4013, 2024 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-39022948

RESUMO

This study aimed to explore the effects of different disturbances on the fungal communities in the sediments of the Jialing River in order to provide scientific basis for the protection of the river ecosystem. The fungal community in the sediments of the main stream of the Jialing River was taken as the research object, and high-throughput sequencing and bioinformatics techniques were used to analyze the differences in the composition and function of fungal communities in river sediment of different types of disturbance (project disturbance, tributary disturbance, sand mining disturbance, and reclamation disturbance) and non-disturbance sections. The results showed that: ① The reclamation and project disturbances significantly inhibited the diversity and richness of fungal communities (P<0.05). The tributary disturbance increased the richness of fungal communities, whereas the impact of sand mining disturbance on sediment fungal communities was not significant. ② The diversity and composition of fungal communities tended to be similar at the different sampling sites in the section with low input of exogenous substances (non-disturbance and sand mining disturbance), whereas there were obvious differences in the diversity of fungal communities at the different sampling sites of high input of external substances (tributary disturbance, project disturbance, and reclamation disturbance) sections. ③ Ascomycota, Rozellomycota, and Basidiomycota were the main dominant fungal phyla in the sediments of the Jialing River. The relative abundance of Rozellomycota was the highest in the sand mining interference section, and the relative abundance of Basidiomycota was the highest in the tributary interference section. Project disturbance significantly increased the relative abundance of saprotrophs, animal pathogens, plant pathogens, and dung saprotrophs, whereas other disturbances inhibited the relative abundance of fungal parasitic fungi, plant pathogens, and plant saprophytes. In conclusion, human disturbance has caused changes in fungal diversity, community structure, and function in the sediment of the Jialing River, and xenobiotic input was a key factor contributing to this phenomenon. The results can provide a reference for predicting and evaluating the ecological quality of river sediments.


Assuntos
Fungos , Sedimentos Geológicos , Rios , Rios/microbiologia , Sedimentos Geológicos/microbiologia , Sedimentos Geológicos/química , Fungos/classificação , China , Ecossistema , Biodiversidade , Monitoramento Ambiental
11.
J Cardiothorac Surg ; 19(1): 451, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014489

RESUMO

BACKGROUND: Cardiac arrest after coronary artery bypass grafting (CABG) is a serious complication with low survival rate. The prognosis of patients with cardiac arrest in the general ward is worse than that in the intensive care unit (ICU) because of the delayed and poor rescue conditions. METHODS: This retrospective study included patients who experienced cardiac arrest after CABG surgery between January 2010 and December 2019 at the Fuwai Hospital. Differences in cardiac arrest between the ICU and the general ward were compared. The patients were divided into shockable and non-shockable rhythm groups, and the differences between the two groups were compared. Finally, we proposed a management protocol for cardiac arrest in the general ward. RESULTS: We retrospectively analyzed 41,450 patients who underwent CABG only, of whom 231 (0.56%) experienced cardiac arrest post-surgery in the ICU (185/231) or in the general ward (46/231). The rescue success rate and 30-day survival rate of the patients with cardiac arrest in the general ward were 76.1% (35/46) and 58.7% (27/46), respectively. The incidence of the different arrhythmia types of cardiac arrest in the general ward compared with that in the ICU was different (P = 0.010). The 30-day survival rate of the non-shockable rhythm group was 31.8% (7/22), which was worse than that of the shockable rhythm group (83.3% [20/24]; P = 0.001). Kaplan-Meier survival analysis showed that the prognosis of the non-shockable group was poor (P < 0.001). CONCLUSIONS: The incidence of cardiac arrest after CABG was low. The prognosis of patients in the general ward was worse than that of those in the ICU. The proportion of non-shockable rhythm type cardiac arrest was higher in the general ward than in the ICU, and patients in this group had a worse early prognosis.


Assuntos
Ponte de Artéria Coronária , Parada Cardíaca , Complicações Pós-Operatórias , Humanos , Ponte de Artéria Coronária/efeitos adversos , Estudos Retrospectivos , Masculino , Feminino , Parada Cardíaca/etiologia , Parada Cardíaca/epidemiologia , Pessoa de Meia-Idade , Idoso , Complicações Pós-Operatórias/epidemiologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Taxa de Sobrevida/tendências , Reanimação Cardiopulmonar , Incidência
12.
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
13.
bioRxiv ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38948818

RESUMO

Conductive hydrogels have gained interest in biomedical applications and soft electronics. To tackle the challenge of ionic hydrogels falling short of desired mechanical properties in previous studies, our investigation aimed to understand the pivotal structural factors that impact the conductivity and mechanical behavior of polyethylene glycol (PEG)-based hydrogels with ionic conductivity. Polyether urethane diacrylamide (PEUDAm), a functionalized long-chain macromer based on PEG, was used to synthesize hydrogels with ionic conductivity conferred by incorporating ions into the liquid phase of hydrogel. The impact of salt concentration, water content, temperature, and gel formation on both mechanical properties and conductivity was characterized to establish parameters for tuning hydrogel properties. To further expand the range of conductivity available in these ionic hydrogels, 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) was incorporated as a single copolymer network or double network configuration. As expected, conductivity in these ionic gels was primarily driven by ion diffusivity and charge density, which was dependent on hydrogel network formation and swelling. Copolymer network structure had minimal effect on the conductivity which was primarily driven by counter-ion equilibrium; however, the mechanical properties and equilibrium swelling was strongly dependent on network structure. The structure-property relationships elucidated here enables the rationale design of this new double network hydrogel to achieve target properties for a broad range of applications.

14.
Se Pu ; 42(7): 711-720, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-38966979

RESUMO

Protein citrullination is an irreversible post-translational modification process regulated by peptidylarginine deiminases (PADs) in the presence of Ca2+. This process is closely related to the occurrence and development of autoimmune diseases, cancers, neurological disorders, cardiovascular and cerebrovascular diseases, and other major diseases. The analysis of protein citrullination by biomass spectrometry confronts great challenges owing to its low abundance, lack of affinity tags, small mass-to-charge ratio change, and susceptibility to isotopic and deamidation interferences. The methods commonly used to study the protein citrullination mainly involve the chemical derivatization of the urea group of the guanine side chain of the peptide to increase the mass-to-charge ratio difference of the citrullinated peptide. Affinity-enriched labels are then introduced to effectively improve the sensitivity and accuracy of protein citrullination by mass spectrometry. 2,3-Butanedione or phenylglyoxal compounds are often used as derivatization reagents to increase the mass-to-charge ratio difference of the citrullinated peptide, and the resulting derivatives have been observed to contain α-dicarbonyl structures. To date, however, no relevant studies on the reactivity of dicarbonyl compounds with citrullinated peptides have been reported. In this study, we determined whether six α-dicarbonyl and two ß-dicarbonyl compounds undergo derivatization reactions with standard citrullinated peptides using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Among the α-dicarbonyl compounds, 2,3-butanedione and glyoxal reacted efficiently with several standard citrullinated peptides, but yielded a series of by-products. Phenylglyoxal, methylglyoxal, 1,2-cyclohexanedione, and 1,10-phenanthroline-5,6-dione also derivated efficiently with standard citrullinated peptides, generating a single derivative. Thus, a new derivatization method that could yield a single derivative was identified. Among the ß-dicarbonyl compounds, 1,3-cyclohexanedione and 2,4-pentanedione successfully reacted with the standard citrullinated peptides, and generated a single derivative. However, their reaction efficiency was very low, indicating that the ß-dicarbonyl compounds are unsuitable for the chemical derivatization of citrullinated peptides. The above results indicate that the α-dicarbonyl structure is necessary for realizing the efficient and specific chemical derivatization of citrullinated peptides. Moreover, the side chains of the α-dicarbonyl structure determine the structure of the derivatives, derivatization efficiency, and generation (or otherwise) of by-products. Therefore, the specific enrichment and precise identification of citrullinated peptides can be achieved by synthesizing α-dicarbonyl structured compounds containing affinity tags. The proposed method enables the identification of citrullinated proteins and their modified sites by MS, thereby providing a better understanding of the distribution of citrullinated proteins in different tissues. The findings will be beneficial for studies on the mechanism of action of citrullinated proteins in a variety of diseases.


Assuntos
Citrulinação , Peptídeos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Peptídeos/química
15.
Nano Lett ; 24(28): 8696-8701, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38967319

RESUMO

DNA nanotubes with controllable geometries hold a wide range of interdisciplinary applications. When preparing DNA nanotubes of varying widths or distinct chirality, existing methods require repeatedly designing and synthesizing specific DNA sequences, which can be costly and laborious. Here, we proposed an intercalator-assisted DNA tile assembly method which enables the production of DNA nanotubes of diverse widths and chirality using identical DNA strands. Through adjusting the concentration of intercalators during assembly, the twisting direction and extent of DNA tiles could be modulated, leading to the formation of DNA nanotubes featuring controllable widths and chirality. Moreover, through introducing additional intercalators and secondary annealing, right-handed nanotubes could be reconfigured into distinct left-handed nanotubes. We expect that this method could be universally applied to modulating the self-assembly pathways of various DNA tiles and other chiral materials, advancing the landscape of DNA tile assembly.


Assuntos
DNA , Nanotubos , Nanotubos/química , Nanotubos/ultraestrutura , DNA/química , Conformação de Ácido Nucleico , Nanotecnologia/métodos , Substâncias Intercalantes/química , Estereoisomerismo
16.
Apoptosis ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886311

RESUMO

Disulfidptosis is a novel form of cell death that is distinguishable from established programmed cell death pathways such as apoptosis, pyroptosis, autophagy, ferroptosis, and oxeiptosis. This process is characterized by the rapid depletion of nicotinamide adenine dinucleotide phosphate (NADPH) in cells and high expression of solute carrier family 7 member 11 (SLC7A11) during glucose starvation, resulting in abnormal cystine accumulation, which subsequently induces andabnormal disulfide bond formation in actin cytoskeleton proteins, culminating in actin network collapse and disulfidptosis. This review aimed to summarize the underlying mechanisms, influencing factors, comparisons with traditional cell death pathways, associations with related diseases, application prospects, and future research directions related to disulfidptosis.

17.
Plants (Basel) ; 13(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38891313

RESUMO

Vanilla (Vanilla planifolia Andrews) is a valuable orchid spice cultivated for its highly priced beans. Vanilla has been planted in Hainan province of China via cutting propagation for about 40 years. The yield has been decreasing annually for the past ten years due to pod numbers declining significantly even though it seems to grow normally without disease symptoms, while the reason is still unknown. In this study, we found that Cymbidium mosaic virus (CymMV), one of the most devastating viruses causing losses in the vanilla industry, massively presented within the pods and leaves of vanilla plants, so the virus infecting the vanilla seems to be a highly probable hypothesis of the main contributions to low yield via decreasing the number of pods. This represents the first speculation of CymMV possibly affecting the yield of vanilla in China, indicating the important role of virus elimination in restoring high yield in vanilla. This research can also serve as a warning to important economic crops that rely on cuttings for propagation, demonstrating that regular virus elimination is very important for these economically propagated crops through cuttings.

18.
Acta Pharmacol Sin ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942954

RESUMO

C/EBP homologous protein (CHOP) triggers the death of multiple cancers via endoplasmic reticulum (ER) stress. However, the function and regulatory mechanism of CHOP in liver cancer remain elusive. We have reported that late endosomal/lysosomal adapter, mitogen-activated protein kinase and mTOR activator 5 (LAMTOR5) suppresses apoptosis in various cancers. Here, we show that the transcriptional and posttranscriptional inactivation of CHOP mediated by LAMTOR5 accelerates liver cancer growth. Clinical bioinformatic analysis revealed that the expression of CHOP was low in liver cancer tissues and that its increased expression predicted a good prognosis. Elevated CHOP contributed to destruction of LAMTOR5-induced apoptotic suppression and proliferation. Mechanistically, LAMTOR5-recruited DNA methyltransferase 1 (DNMT1) to the CpG3 region (-559/-429) of the CHOP promoter and potentiated its hypermethylation to block its interaction with general transcription factor IIi (TFII-I), resulting in its inactivation. Moreover, LAMTOR5-enhanced miR-182/miR-769 reduced CHOP expression by targeting its 3'UTR. Notably, lenvatinib, a first-line targeted therapy for liver cancer, could target the LAMTOR5/CHOP axis to prevent liver cancer progression. Accordingly, LAMTOR5-mediated silencing of CHOP via the regulation of ER stress-related apoptosis promotes liver cancer growth, providing a theoretical basis for the use of lenvatinib for the treatment of liver cancer.

19.
Nat Commun ; 15(1): 5255, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898050

RESUMO

GPRC5D is an atypical Class C orphan G protein-coupled receptor. Its high expression on the surface of multiple myeloma cells has rendered it an attractive target for therapeutic interventions, including monoclonal antibodies, CAR-T cells, and T-cell engagers. Despite its therapeutic potential, the insufficient understanding regarding of the receptor's structure and antibody recognition mechanism has impeded the progress of effective therapeutic development. Here, we present the structure of GPRC5D in complex with a preclinical-stage single-chain antibody (scFv). Our structural analysis reveals that the GPRC5D presents a close resemblance to the typical Class C GPCRs in the transmembrane region. We identify a distinct head-to-head homodimer arrangement and interface mainly involving TM4, setting it apart from other Class C homo- or hetero-dimers. Furthermore, we elucidate the binding site engaging a sizable extracellular domain on GPRC5D for scFv recognition. These insights not only unveil the distinctive dimer organization of this unconventional Class C GPCR but also hold the potential to advance drug development targeting GPRC5D for the treatment of multiple myeloma.


Assuntos
Mieloma Múltiplo , Multimerização Proteica , Receptores Acoplados a Proteínas G , Anticorpos de Cadeia Única , Humanos , Mieloma Múltiplo/imunologia , Receptores Acoplados a Proteínas G/imunologia , Receptores Acoplados a Proteínas G/metabolismo , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/metabolismo , Ligação Proteica , Sítios de Ligação , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/química
20.
Foods ; 13(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38928755

RESUMO

Fermented vegetable products play a significant role in various cuisines, and understanding the fermentation dynamics of lactic acid bacteria (LAB) strains is essential for optimizing their production and quality. Here, we sought to investigate the fermentation performance of five LAB strains isolated from Sichuan paocai as starters for paocai. Sensory evaluation revealed that the inoculation of radish paocai samples with LAB strains effectively improved the overall liking and sensory satisfaction of participants, increasing the scores to varying degrees in terms of taste, flavor, texture, and coloration. Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus exhibited a good salt resistance in radish juice and could grow in a medium containing 10% NaCl. Four indicator strains commonly found in contaminated paocai were effectively inhibited by fermented LAB broths, which improved the edibility and safe production of paocai. Compared to spontaneous fermentation (CK), radish paocai inoculated with LAB showed a significantly accelerated acid production rate, shortening the fermentation period by approximately two days. The contents of titratable total acids, organic acids, and free amino acids were higher in the inoculated samples and were enriched in the taste of radish paocai. The content of volatile organic compounds in the inoculated samples was higher than that in CK. Based on OPLS-DA analysis, 31 key indicators of paocai quality were screened and used to rank the fermentation performances of the five strains using the TOPSIS method; here, Lpb. plantarum and Lcb. rhamnosus achieved the highest scores. This study provides a reference for selecting LAB strains as efficient and secure fermentation starters to optimize paocai quality.

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