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1.
Artigo em Inglês | MEDLINE | ID: mdl-39358914

RESUMO

Free fatty acids (FFAs) have emerged as significant risk factors for atherosclerosis (AS). Prolonged exposure to FFAs induces vascular endothelial injury, including inflammatory responses and oxidative stress, which are central events in AS. Chromofungin (CHR), a peptide derived from chromogranin A (CGA), has been implicated in various biological functions. However, its physiological roles in endothelial biology and its involvement in the pathological development of AS have not been previously reported. In the present study, we investigated the underlying mechanisms through which CHR exerts its beneficial effects on FFA-challenged human aortic endothelial cells (HAECs). We found that treatment with CHR ameliorated the FFA-induced reduction in cell viability and increase in lactate dehydrogenase (LDH) release. Additionally, CHR mitigated oxidative stress by reducing mitochondrial reactive oxygen species (ROS) levels and increasing superoxide dismutase (SOD) activity. Furthermore, exposure to FFAs increased NADPH oxidase (NOX) 4 expression at both the mRNA and protein levels, which were attenuated by CHR in a dose-dependent manner. Notably, CHR reduced the levels of nucleotide-binding domain and leucine-rich repeat-containing (NLR) family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), and cleaved caspase-1 (p10), key components of the NLRP3 inflammasome complex, as well as interleukin 1ß (IL-1ß) and interleukin-18 (IL-18) expression. Mechanistically, it was demonstrated that FFAs reduced the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), which were rescued by CHR in a dose-dependent manner. Conversely, inhibition of AMPK with its specific inhibitor compound C abolished the protective effects of CHR against FFA-induced activation of the NLRP3 inflammasome in HAECs. Based on these findings, we conclude that CHR may serve as a promising agent for maintaining normal endothelial cell function and treating AS.

2.
Front Microbiol ; 15: 1462459, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39376701

RESUMO

Lytic bacteriophages (phages) are promising clinically viable therapeutic options against carbapenem-resistant Klebsiella pneumoniae (CRKP). In China, the predominant strains are those assigned to sequence type 11 and capsular type 64 (ST11-KL64). The emergence of phage resistance is a major bottleneck hindering effective phage therapy, requiring more new phages to provide the flexibility for creating different phage cocktails. However, the majority of phages against ST11-KL64 CRKP belong to the genus Przondovirus of the family Autographiviridae, which limits the options for constructing cocktails. We recovered a novel lytic phage of the genus Taipeivirus within the family Ackermannviridae against ST11-KL64 CRKP from a river in China. We phenotypically characterized this phage and obtained its genome sequence for analysis. This phage can inhibit the growth of ST11-KL64 CRKP for 6.5 h at a 0.1 multiplicity of infection and exhibits a narrow host range, being unable to attack CRKP strains of the other 30 capsular types. This phage carries no genes encoding antimicrobial resistance, virulence, or lysogeny. It is stable across a wide range of temperatures and pH values, making it suitable for phage therapy. Unlike other Taipeivirus phages, P01 has two tail spike proteins and a unique tail fiber protein. The distinct tail composition of this phage contributes to its activity against ST11-KL64 CRKP and its narrow host range. Taken together, we recovered a phage of a novel viral species with the potential for therapy, which expands the phage biobank against CRKP.

3.
Sci Total Environ ; 955: 177147, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39442719

RESUMO

Organophosphate esters (OPEs) have attracted extensive attention due to their toxic effects on human health and biological systems as plasticizers and flame retardants. This study focused on exploring a green approach to get toxicity mechanisms that used less solvents or organisms. The toxicity values of selected organophosphate esters including tri (2-chloroethyl) phosphate (TCEP), tri (1, 3-dichloro-2-propyl) phosphate (TDCP), tripropyl phosphate (TPrP), tri-n-butyl phosphate (TnBP), and tritolyl Phosphate (TCrP) to Photobacterium phosphoreum were determined. Their EC50 range was between 7.27 × 10-8-5.12 × 10-6 mol/L. Based on molecular dynamics simulation the data of binding affinity between OPEs and n-octanol / phospholipid bilayer were calculated respectively. Coupling with binding affinity energies and toxicity values, the mode of action (MOA) of OPEs including types of reactive or anesthetic mechanism could be fast deduced. The proposed hypothesis of n-octanol (C8H18O) as a virtual biofilm to replace phospholipid bilayer was verified. The alternative green approach could simplify toxicity assay and realize fast predicting MOA for different chemicals and model organisms.

4.
J Clin Invest ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39405126

RESUMO

Impaired fatty acid oxidation (FAO) and the therapeutic benefits of FAO restoration have been revealed in sepsis. However, the regulatory factors contributing to FAO dysfunction during sepsis remain inadequately clarified. In this study, we identified a subset of lipid-associated macrophages characterized by high expression of trigger receptor expressed on myeloid cells 2 (TREM2) and demonstrated that TREM2 acted as a suppressor of FAO to increase the susceptibility to sepsis. TREM2 expression was markedly up-regulated in sepsis patients and correlated with the severity of sepsis. Knock out of TREM2 in macrophages improved the survival rate and reduced inflammation and organ injuries of sepsis mice. Notably, TREM2-deficient mice exhibited decreased triglyceride accumulation and an enhanced FAO rate. Further observations showed that the blockade of FAO substantially abolished the alleviated symptoms observed in TREM2 knockout mice. Mechanically, we demonstrated that TREM2 interacted with the phosphatase SHP1 to inhibit Bruton tyrosine kinas (BTK)-mediated FAO in sepsis. Our findings expand the understanding of FAO dysfunction in sepsis and reveal TREM2 as a critical regulator of FAO, which may provide a promising target for the clinical treatment of sepsis.

5.
BMC Med Educ ; 24(1): 1120, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39390538

RESUMO

BACKGROUND: As the global elderly population rises, providing quality care for older adults is increasingly challenging. Rehabilitation technicians are crucial in this effort. Their knowledge and attitudes significantly impact care quality and their willingness to work with the elderly. While many studies have examined healthcare professionals' attitudes toward older adults, few focus on rehabilitation students. This study assesses Chinese rehabilitation students' knowledge of aging, attitudes toward older individuals, willingness to care for them, and the factors influencing these aspects. METHODS: A sample of 890 rehabilitation students from three colleges and universities in southwestern China was investigated with a self-administered questionnaire, which included socio-demographic information, the Palmore Facts on Aging Quiz, the Kogan's Attitude towards Older People Scale and the Chinese Version of the Interpersonal Reactivity Index. Data analyses were conducted using SPSS version 25.0. Descriptive statistics were used to illustrate the demographic characteristics of the respondents. The frequency and percentage of responses was calculated. Means and standard deviations were computed for general knowledge of aging, attitudes toward older people, and empathy. Independent t-tests and one-way ANOVA assessed differences in FAQ, KAOP, and IRI-C scores between groups. Pearson's correlation examined correlations among general knowledge of aging, attitudes toward older people and empathy ability. Chi-square or Fisher's exact tests compared willingness to engage in geriatric rehabilitation across different respondent characteristics. Hierarchical multiple regression analysis explored the independent effect of different variables on attitudes toward older people. RESULTS: The Chinese rehabilitation students from three colleges and universities in southwestern China displayed a relatively low level of knowledge about aging, but a generally positive attitude towards older people. Females had significantly more positive attitudes toward older people than males(p<0.01). The students who had previous experience of being cared for by (maternal) grandparents, living with the elderly, and taking care of the elderly showed significantly more positive attitudes toward older people (p = 0.001, 0.007 and 0.007, respectively) and a significantly stronger willingness to engage in geriatric rehabilitation(p = 0.013, <0.01 and <0.01, respectively) than those who had not had these experiences. Students with good relationships with older people had more positive attitudes toward the elderly (p < 0.01) and greater willingness to engage in geriatric rehabilitation (p < 0.01). Those with frequent contact with the elderly also showed more positive attitudes (p < 0.01) and a stronger willingness to engage in geriatric rehabilitation (p = 0.002) compared to those with less contact. Knowledge of aging and empathy ability were both significantly positively related to attitudes toward older people and both independent predictors of attitudes toward older people(r = 0.143, p<0.01 and r = 0.337, p<0.01). CONCLUSIONS: It is crucial to prepare rehabilitation students with adequate knowledge and positive attitudes to ensure the quality of rehabilitation and care provided to older people. Educators should adopt effective strategies to promote rehabilitation students' geriatric rehabilitation knowledge and increase their positive attitudes toward older people.


Assuntos
Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , China , Masculino , Estudos Transversais , Feminino , Adulto Jovem , Adulto , Envelhecimento/psicologia , Inquéritos e Questionários , Idoso , Reabilitação/educação , Geriatria/educação , Estudantes de Ciências da Saúde/psicologia
6.
Adv Sci (Weinh) ; : e2309631, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39467150

RESUMO

Immunotherapies employing PD-1/PD-L1 immune checkpoint inhibitors (ICIs) are vital for primary liver cancer (PLC), but response rates remain unsatisfying. Accurate differentiation of responders from non-responders to immunotherapy is imperative. Here, single-cell-scaled mass cytometry analysis on sequential peripheral blood mononuclear cells (PBMCs) from ICI-treated PLC patients is conducted, and tissue residence of immune subpopulations is assessed via multiplex immunohistochemistry. In the discovery cohort (n = 24), responders have lower baseline B cell and HLA-DR+CD8+T cell, and higher CD14+CD16- classical monocyte (CM) proportions. CMs decrease more in responders PBMCs, while HLA-DR+CD8+T cells conformably amplify after ICI-exposure. Responsive individuals display upregulated exhaustion and activation markers in peripheral immune lineages. In the expanded cohort of 77 patients, the augment of the B cells in non-responders is re-confirmed. Responders demonstrate much higher enrichment of B cells or tertiary lymphoid structures in tumor compared to non-responders. A prospective model that excelled in early discrimination of responders is developed using generalized linear model and achieves a satisfactory AUC over 0.9 in all three independent cohorts. Integratedly, the study unveils dynamic immune landscapes in PLC patients undergoing ICI-based therapy, aiding in PLC patient stratification for ICI-based treatment and fostering new response monitoring strategies.

7.
Clin Liver Dis ; 28(4): 663-679, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39362714

RESUMO

Alcohol-associated liver disease (ALD) poses a significant global public health challenge, with high patient mortality rates and economic burden. The gut microbiome plays an important role in the onset and progression of alcohol-associated liver disease. Excessive alcohol consumption disrupts the intestinal barrier, facilitating the entry of harmful microbes and their products into the liver, exacerbating liver damage. Dysbiosis, marked by imbalance in gut bacteria, correlates with ALD severity. Promising microbiota-centered therapies include probiotics, phages, and fecal microbiota transplantation. Clinical trials demonstrate the potential of these interventions to improve liver function and patient outcomes, offering a new frontier in ALD treatment.


Assuntos
Disbiose , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Hepatopatias Alcoólicas , Probióticos , Hepatopatias Alcoólicas/microbiologia , Hepatopatias Alcoólicas/terapia , Probióticos/uso terapêutico , Testes de Função Hepática
8.
Microbiol Resour Announc ; : e0098124, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39436064

RESUMO

Carbapenem-resistant Klebsiella pneumoniae (CRKP) of sequence type 11 (ST11) and capsular type KL47 or KL64 are dominant in China. We report the draft genome sequence of an ST11 blaKPC-2-carrying CRKP strain belonging to uncommon capsular type KL62. This strain carries virulence factors encoding multiple iron acquisition systems and mucoid regulators.

9.
Small ; : e2405946, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39246162

RESUMO

Under large current densities, the excessive hydroxide ion (OH) consumption hampers alkaline water splitting involving the oxygen evolution reaction (OER). High OH concentration (≈30 wt.%) is often used to enhance the catalytic activity of OER, but it also leads to higher corrosion in practical systems. To achieve higher catalytic activity in low OH concentration, catalysts on magnetic frame (CMF) are built to utilize the local magnetic convection induced from the host frame's magnetic field distributions. This way, a higher reaction rate can be achieved in relatively lower OH concentrations. A CMF model system with catalytically active CoFeOx nanograins grown on the magnetic Ni foam is demonstrated. The OER current of CoFeOx@NF receives ≈90% enhancement under 400 mT (900 mA cm-2 at 1.65 V) compared to that in zero field, and exhibits remarkable durability over 120 h. As a demonstration, the water-splitting performance sees a maximum 45% magnetic enhancement under 400 mT in 1 m KOH (700 mA cm-2 at 2.4 V), equivalent to the concentration enhancement of the same electrode in a more corrosive 2 m KOH electrolyte. Therefore, the catalyst-on-magnetic-frame strategy can make efficient use of the catalysts and achieve higher catalytic activity in low OH concentration by harvesting local magnetic convection.

10.
Cancer Biol Ther ; 25(1): 2398297, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-39223776

RESUMO

Breast cancer ranks the first in the incidence of female cancer and is the most common cancer threatening the life and health of women worldwide.Tumor protein p53-regulated apoptosis-inducing protein 1 (TP53AIP1) is a pro-apoptotic gene downstream of p53. However, the role of TP53AIP1 in BC needs to be investigated. In vitro and in vivo experiments were conducted to assess the biological functions and associated mechanisms. Several bioinformatics analyses were made, CCK8 assay, wound healing, transwell assays, colony formation assay, EDU, flow cytometry, Immunofluorescence, qRT-PCR and Western-blotting were performed. In our study, we discovered that BC samples had low levels of TP53AIP1 expression, which correlated with a lower survival rate in BC patients. When TP53AIP1 was up-regulated, it caused a decrease in cell proliferation, migration, and invasion. It also induced epithelial-to-mesenchymal transition (EMT) and protective autophagy. Furthermore, the over-expression of TP53AIP1 suppressed tumor growth when tested in vivo. We also noticed that TP53AIP1 up-regulation resulted in decreased levels of phosphorylation in AKT and mTOR, suggesting a mechanistic role. In addition, we performed functional rescue experiments where the activation of AKT was able to counteract the impact of TP53AIP1 on the survival and autophagy in breast cancer cell lines. This suggests that TP53AIP1 acts as an oncogene by controlling the AKT/mTOR pathway. These findings reveal TP53AIP1 as a gene that suppresses tumor growth and triggers autophagy through the AKT/mTOR pathway in breast cancer cells. As a result, TP53AIP1 presents itself as a potential target for novel therapeutic approaches in treating breast cancer.


Assuntos
Proteínas Reguladoras de Apoptose , Autofagia , Neoplasias da Mama , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR , Animais , Feminino , Humanos , Camundongos , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/genética , Autofagia/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
11.
Int J Biol Macromol ; 279(Pt 1): 135180, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39214213

RESUMO

Sonodynamic therapy has attracted much attention as a noninvasive treatment for deep infections. However, it is challenging to achieve high antibacterial activity for hydrogels under ultrasonic irradiation due to the relatively weak sono-catalysis capability of sonosensitizers. Herein, an ultrasound-responsive antibacterial hydrogel (Fe3O4/HA/Ber-LA) composed of Fe3O4-grafted-Berberine, chitosan molecules modified with L-arginine and poly (vinyl alcohol) is prepared for enhanced sonodynamic therapy and immunoregulation. The formation of heterojunction between berberine and Fe3O4 with different work function promotes the charge separation and electron flow and disrupts the conjugated structure of berberine, causing a significant decrease in the band gap, eventually enhancing the sonocatalytic activity. The combination of berberine with Fe3O4 also significantly improves the oxygen adsorption energy, enabling more O2 molecules to react with the electron-rich regions on the surface of Fe3O4 to generate more reactive oxygen species (ROS). L-arginine grafted in the hydrogel is catalyzed by the ROS to release nitric oxide, which not only possesses antibacterial activity, but also positively affects macrophage M1 polarization to display potent phagocytosis to Staphylococcus aureus, thus achieving immuno-sonodynamic therapy. Hence, Fe3O4/HA/Ber-LA hydrogel under ultrasound irradiation shows excellent antibacterial activity. Furthermore, the antioxidative activity and anti-inflammatory effect of berberine released from the hybrid hydrogel induces macrophages to polarize towards the anti-inflammatory M2 status as infection comes under control, thus accelerating the wound healing. The hybrid hydrogel based on the immuno-sonodynamic therapy may be an extraordinary candidate for the treatment of deep infections.


Assuntos
Antibacterianos , Quitosana , Hidrogéis , Staphylococcus aureus , Terapia por Ultrassom , Cicatrização , Quitosana/química , Quitosana/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Camundongos , Hidrogéis/química , Hidrogéis/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Terapia por Ultrassom/métodos , Berberina/farmacologia , Berberina/química , Ondas Ultrassônicas , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Óxido Nítrico/metabolismo
12.
Microb Cell ; 11: 328-338, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39206205

RESUMO

Alcohol-associated liver disease is highly prevalent worldwide, with alcohol-associated hepatitis as a severe form characterized by substantial morbidity, mortality, and economic burden. Gut bacterial dysbiosis has been linked to progression of alcohol-associated hepatitis. Fecal cytolysin secreted by the pathobiont Enterococcus faecalis (E. faecalis) is associated with increased mortality in patients with alcohol-associated hepatitis. Although gelatinase is considered a virulence factor in E. faecalis, its prevalence and impact on alcohol-associated hepatitis patient outcomes remains unclear. In this study, 20 out of 65 (30.8%) patients with alcohol-associated hepatitis tested positive for gelatinase in their stool. There were no significant differences in 30-day and 90-day mortality between gelatinase-positive and gelatinase-negative patients (p=0.97 and p=0.48, respectively). Fecal gelatinase had a low discriminative ability for 30-day mortality (area under the curve [AUC] 0.50 vs fibrosis-4 Index (FIB-4) 0.75) and 90-day mortality compared with other established liver disease markers (AUC 0.57 vs FIB-4 0.79 or 'age, serum bilirubin, INR, and serum creatinine' (ABIC) score 0.78). Furthermore, fecal gelatinase was not an important feature for 30-day or 90-day mortality per random forest analysis. Finally, gelatinase-positive patients with alcohol-associated hepatitis did not exhibit more severe liver disease compared with gelatinase-negative patients. In conclusion, fecal gelatinase does not predict mortality or disease severity in patients with alcohol-associated hepatitis from our cohort.

13.
Cell Rep ; 43(8): 114602, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39137112

RESUMO

Klebsiella aerogenes is an understudied and clinically important pathogen. We therefore investigate its population structure by genome analysis aligned with metadata. We sequence 130 non-duplicated K. aerogenes clinical isolates and identify two inter-patient transmission events. We then retrieve all publicly available K. aerogenes genomes (n = 1,026, accessed by January 1, 2023) and analyze them with our 130 genomes. We develop a core-genome multi-locus sequence-typing scheme. We find that K. aerogenes is a species complex comprising four phylogroups undergoing evolutionary divergence, likely forming three species. We delineate remarkable clonal diversity and identify three worldwide-distributed carbapenemase-encoding clonal clusters, representing high-risk lineages. We uncover that K. aerogenes has an open genome equipped by a large arsenal of antimicrobial resistance genes. We identify two genetic regions specific for K. aerogenes, encoding a type VI secretion system and flagella/chemotaxis for motility, respectively, both contributing to the virulence. These results provide much-needed insights into the population structure and pan-genomes of K. aerogenes.


Assuntos
Enterobacter aerogenes , Genoma Bacteriano , Virulência/genética , Humanos , Enterobacter aerogenes/genética , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/patogenicidade , Farmacorresistência Bacteriana/genética , Filogenia , Genômica/métodos , Fatores de Virulência/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/epidemiologia
14.
Biomed Pharmacother ; 179: 117349, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39191028

RESUMO

OBJECT: Adipose-derived mesenchymal stem cells (ADSCs) have received significant attention in the field of cartilage tissue repair. Angelica sinensis polysaccharide (ASP) can enhance both the proliferation and differentiation of mesenchymal stem cells. Therefore, we intend to explore the effect of ASP on chondrogenic differentiation of ADSCs in vitro, and elucidate the underlying mechanisms. METHOD: ADSCs were treated with different concentrations of ASP to determine the optimal concentration. The chondrogenic differentiation of ADSCs was evaluated using Alcian blue staining, qRT-PCR, western blot, and IF staining. Transcriptome sequencing was performed to identify the expression profiles of ADSCs before and after ASP treatment, followed by bioinformatic analyses including differential expression analysis, enrichment analysis, and construction of PPI networks to identify differentially expressed genes (DEGs) associated with ASP and chondrogenic differentiation. RESULT: Surface markers of isolated rat-derived ADSCs were identified by CD44+CD90+CD45-CD106-, and exhibited the capacity for lipogenic, osteogenic, and chondrogenic differentiation. With increasing concentration of ASP treatment, there was an upregulation in the activity and acidic mucosubstance of ADSCs. The levels of Aggrecan, COL2A1, and Sox9 showed an increase in ADSCs after 28 days of 80 µg/ml ASP treatment. Transcriptome sequencing revealed that ASP-associated DEGs regulate extracellular matrix synthesis, immune response, inflammatory response, and cell cycle, and are involved in the NF-κB, AGE-RAGE, and calcium pathways. Moreover, Edn1, Frzb, Mdk, Nog, and Sulf1 are hub genes in DEGs. Notably, ASP upregulated MDK levels in ADSCs, while knockdown of MDK mitigated ASP-induced elevations in acidic mucosubstance, chondrogenic differentiation-related markers (Aggrecan, COL2A1, and Sox9), and the activity of the PI3K/AKT pathway. CONCLUSION: ASP enhances the proliferation and chondrogenic differentiation of ADSCs by activating the MDK-mediated PI3K/AKT pathway.


Assuntos
Angelica sinensis , Diferenciação Celular , Condrogênese , Células-Tronco Mesenquimais , Polissacarídeos , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Polissacarídeos/farmacologia , Condrogênese/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Angelica sinensis/química , Transdução de Sinais/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Ratos , Tecido Adiposo/citologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Células Cultivadas , Masculino
15.
Mol Med ; 30(1): 99, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982366

RESUMO

BACKGROUND: Enhanced glycolysis is a crucial metabolic event that drives the development of liver fibrosis, but the molecular mechanisms have not been fully understood. Lactate is the endproduct of glycolysis, which has recently been identified as a bioactive metabolite binding to G-protein-coupled receptor 81 (GPR81). We then questioned whether GPR81 is implicated in the development of liver fibrosis. METHODS: The level of GPR81 was determined in mice with carbon tetrachloride (CCl4)-induced liver fibrosis and in transforming growth factor beta 1 (TGF-ß1)-activated hepatic stellate cells (HSCs) LX-2. To investigate the significance of GPR81 in liver fibrosis, wild-type (WT) and GPR81 knockout (KO) mice were exposed to CCl4, and then the degree of liver fibrosis was determined. In addition, the GPR81 agonist 3,5-dihydroxybenzoic acid (DHBA) was supplemented in CCl4-challenged mice and TGF-ß1-activated LX-2 cells to further investigate the pathological roles of GPR81 on HSCs activation. RESULTS: CCl4 exposure or TGF-ß1 stimulation significantly upregulated the expression of GPR81, while deletion of GPR81 alleviated CCl4-induced elevation of aminotransferase, production of pro-inflammatory cytokines, and deposition of collagen. Consistently, the production of TGF-ß1, the expression of alpha-smooth muscle actin (α-SMA) and collagen I (COL1A1), as well as the elevation of hydroxyproline were suppressed in GPR81 deficient mice. Supplementation with DHBA enhanced CCl4-induced liver fibrogenesis in WT mice but not in GPR81 KO mice. DHBA also promoted TGF-ß1-induced LX-2 activation. Mechanistically, GPR81 suppressed cAMP/CREB and then inhibited the expression of Smad7, a negative regulator of Smad3, which resulted in increased phosphorylation of Smad3 and enhanced activation of HSCs. CONCLUSION: GPR81 might be a detrimental factor that promotes the development of liver fibrosis by regulating CREB/Smad7 pathway.


Assuntos
Tetracloreto de Carbono , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Células Estreladas do Fígado , Cirrose Hepática , Camundongos Knockout , Receptores Acoplados a Proteínas G , Transdução de Sinais , Proteína Smad7 , Animais , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/patologia , Cirrose Hepática/etiologia , Cirrose Hepática/induzido quimicamente , Camundongos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Células Estreladas do Fígado/metabolismo , Proteína Smad7/metabolismo , Proteína Smad7/genética , Fator de Crescimento Transformador beta1/metabolismo , Masculino , Humanos , Linhagem Celular , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Deleção de Genes
16.
Commun Biol ; 7(1): 781, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38944651

RESUMO

Macrolide antibiotics, pivotal in clinical therapeutics, are confronting resistance challenges mediated by enzymes like macrolide esterases, which are classified into Ere-type and the less studied Est-type. In this study, we provide the biochemical confirmation of EstX, an Est-type macrolide esterase that initially identified as unknown protein in the 1980s. EstX is capable of hydrolyzing four 16-membered ring macrolides, encompassing both veterinary (tylosin, tidipirosin, and tilmicosin) and human-use (leucomycin A5) antibiotics. It uses typical catalytic triad (Asp233-His261-Ser102) from alpha/beta hydrolase superfamily for ester bond hydrolysis. Further genomic context analysis suggests that the dissemination of estX is likely facilitated by mobile genetic elements such as integrons and transposons. The global distribution study indicates that bacteria harboring the estX gene, predominantly pathogenic species like Escherichia coli, Salmonella enterica, and Klebsiella pneumoniae, are prevalent in 74 countries across 6 continents. Additionally, the emergence timeline of the estX gene suggests its proliferation may be linked to the overuse of macrolide antibiotics. The widespread prevalence and dissemination of Est-type macrolide esterase highlight an urgent need for enhanced monitoring and in-depth research, underlining its significance as an escalating public health issue.


Assuntos
Esterases , Esterases/genética , Esterases/metabolismo , Esterases/química , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Macrolídeos/metabolismo , Humanos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Filogenia , Hidrolases/genética , Hidrolases/metabolismo , Hidrolases/química
17.
BMJ Open ; 14(6): e077903, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858156

RESUMO

INTRODUCTION: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death in China. The combination of immune checkpoint inhibitors (ICIs) and antiangiogenic drugs, such as bevacizumab and tyrosine kinase inhibitors, has been recommended as first-line treatment for advanced HCC. However, two-thirds of patients did not benefit from this form of immunotherapy. Currently, data on the subsequent regimen for patients previously treated with ICIs are lacking. Studies have shown that the combination of radiotherapy (RT) and ICIs is a potentially effective second-line therapy for HCC. This study aims to assess the efficacy and safety of combined therapy with stereotactic body RT (SBRT), sintilimab and IBI305 (a biosimilar of bevacizumab) in patients with HCC following the progression of first-line ICI therapy. METHODS AND ANALYSIS: This study is an open-label, single-arm, single-centre, phase 2 trial of 21 patients with advanced HCC in whom previous ICI therapy has failed. Participants will receive approximately 30-40 Gy/5-8F SBRT, followed by 200 mg sintilimab and 15 mg/kg IBI305 intravenously every 3 weeks. Treatment will continue until the development of unacceptable toxicity or disease progression. We will use Simon's two-stage design, with the objective response rate (ORR) as the primary endpoint. Secondary endpoints include ORR of lesions without RT, disease control rate, progression-free survival, overall survival and safety. ETHICS AND DISSEMINATION: The study was authorised by the Medical Ethics Committee. Dissemination of results will occur via a peer-reviewed publication and other relevant media. TRIAL REGISTRATION NUMBER: ChiCTR2200056068.


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma Hepatocelular , Neoplasias Hepáticas , Radiocirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Carcinoma Hepatocelular/terapia , Ensaios Clínicos Fase II como Assunto , Terapia Combinada , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos , Neoplasias Hepáticas/terapia , Radiocirurgia/métodos , Radiocirurgia/efeitos adversos
18.
RSC Adv ; 14(22): 15637-15646, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38746839

RESUMO

Exploring low-cost and high-performance phosphorus (P) adsorbents is key to controlling P contamination in water. This study evaluated the P adsorption performance of three types of cement: Ordinary Portland cement (OPC), Portland slag cement (PSC), and Portland pozzolana cement (PPC). Furthermore, SEM-EDS, XRD, XPS, and FTIR were employed to reveal the adsorption mechanism. The results showed that the pseudo-second-order model exhibited higher regression coefficients than the pseudo-first-order model, indicating that chemisorption dominated the adsorption process. The Langmuir equation fitted the P adsorption data well, with maximum P adsorption capacities of 245.8, 226.1, and 210.0 mg g-1 for OPC, PSC, and PPC at 25 °C, respectively. P adsorption capacities decreased gradually with increasing initial pH and reached their maximum values at pH 3. The anions of F-, CO32-, and SO42- negatively affected P adsorption due to the competitive adsorption with Ca2+. The results of XPS, XRD, and FTIR confirmed that Ca-P precipitates (i.e., hydroxyapatite) were the main removal mechanism. A real domestic sewage experiment showed that 0.6 g L-1 OPC effectively reduced the P concentration from 2.4 to below 0.2 mg L-1, with a dosage cost of 0.034 $ per ton. This study indicated that cement, as a low-cost and efficient P adsorbent, has great potential for application in removing P from acidic and neutral wastewater.

19.
J Biomed Sci ; 31(1): 55, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38802791

RESUMO

BACKGROUND: Radioresistance is a key clinical constraint on the efficacy of radiotherapy in lung cancer patients. REV1 DNA directed polymerase (REV1) plays an important role in repairing DNA damage and maintaining genomic stability. However, its role in the resistance to radiotherapy in lung cancer is not clear. This study aims to clarify the role of REV1 in lung cancer radioresistance, identify the intrinsic mechanisms involved, and provide a theoretical basis for the clinical translation of this new target for lung cancer treatment. METHODS: The effect of targeting REV1 on the radiosensitivity was verified by in vivo and in vitro experiments. RNA sequencing (RNA-seq) combined with nontargeted metabolomics analysis was used to explore the downstream targets of REV1. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to quantify the content of specific amino acids. The coimmunoprecipitation (co-IP) and GST pull-down assays were used to validate the interaction between proteins. A ubiquitination library screening system was constructed to investigate the regulatory proteins upstream of REV1. RESULTS: Targeting REV1 could enhance the radiosensitivity in vivo, while this effect was not obvious in vitro. RNA sequencing combined with nontargeted metabolomics revealed that the difference result was related to metabolism, and that the expression of glycine, serine, and threonine (Gly/Ser/Thr) metabolism signaling pathways was downregulated following REV1 knockdown. LC-MS/MS demonstrated that REV1 knockdown results in reduced levels of these three amino acids and that cystathionine γ-lyase (CTH) was the key to its function. REV1 enhances the interaction of CTH with the E3 ubiquitin ligase Rad18 and promotes ubiquitination degradation of CTH by Rad18. Screening of the ubiquitination compound library revealed that the ubiquitin-specific peptidase 9 X-linked (USP9X) is the upstream regulatory protein of REV1 by the ubiquitin-proteasome system, which remodels the intracellular Gly/Ser/Thr metabolism. CONCLUSION: USP9X mediates the deubiquitination of REV1, and aberrantly expressed REV1 acts as a scaffolding protein to assist Rad18 in interacting with CTH, promoting the ubiquitination and degradation of CTH and inducing remodeling of the Gly/Ser/Thr metabolism, which leads to radioresistance. A novel inhibitor of REV1, JH-RE-06, was shown to enhance lung cancer cell radiosensitivity, with good prospects for clinical translation.


Assuntos
Neoplasias Pulmonares , Nucleotidiltransferases , Tolerância a Radiação , Ubiquitina-Proteína Ligases , Ubiquitinação , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Linhagem Celular Tumoral , Camundongos , Animais , DNA Polimerase Dirigida por DNA
20.
Polymers (Basel) ; 16(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38611161

RESUMO

In this study, the effects of ambient temperature on the horizontal mechanical performance of isolated rubber bearings were investigated using high-speed reciprocating loading methods. A comprehensive series of 54 experimental trials are performed on the full-scale (900 mm-diameter) isolation rubber bearings, encompassing a range of temperatures (-20 °C, 0 °C, and 23 °C), shear pressures (50%, 100%, and 250%), and frequencies (0.20 Hz, 0.25 Hz, and 0.30 Hz). Because the compression-shear tests were conducted at high velocities and pressures (specifically, vertical compressive stress of 15 MPa), the equipment used in these tests was capable of generating substantial inertial and frictional forces. Appropriate correction methodologies for the precise determination of mechanical performance metrics for bearings are presented. Then, a comprehensive investigation of the effects of various loading conditions on the characteristic strength, post-yield stiffness, horizontal equivalent stiffness, and equivalent damping ratio of LRB900 (lead-core rubber bearings 900 mm-diameter) and LNR900 (linear natural rubber bearings 900 mm-diameter) is conducted. The empirical results show a discernible relationship between these characteristics and ambient temperature as the number of loading cycles increases, except for the equivalent damping ratio. Finally, empirical fitting formulations incorporating the influence of ambient temperature are presented for each performance indicator. These formulas are intended to assist designers in performing seismic design analyses by allowing them to take into consideration the effects of ambient temperature comprehensively.

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