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1.
Angew Chem Int Ed Engl ; : e202417435, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39385458

RESUMO

Photocatalytic reduction of diluted CO2 from anthropogenic sources holds tremendous potential for achieving carbon neutrality, while the huge barrier to forming *COOH key intermediate considerably limits catalytic effectiveness. Herein, via coordination engineering of atomically scattered Ni sites in conductive metal-organic frameworks (CMOFs), we propose a facile strategy for tailoring the d­band center of metal active sites towards high-efficiency photoreduction of diluted CO2. Under visible-light irradiation in pure CO2, CMOFs with Ni-O4 sites (Ni-O4 CMOFs) exhibits an outstanding rate for CO generation of 13.3 µmol h-1 with a selectivity of 94.5%, which is almost double that of its isostructural counterpart with traditional Ni-N4 sites (Ni-N4 CMOFs), outperforming most reported systems under comparable conditions. Interestingly, in simulated flue gas, the CO selectivity of Ni-N4 CMOFs decreases significantly while that of Ni-O4 CMOFs is mostly unchanged, signifying the supremacy for Ni-O4 CMOFs in leveraging anthropogenic diluted CO2. In-situ spectroscopy and density functional theory (DFT) investigations demonstrate that O coordination can move the center of the Ni sites' d-band closer to the Fermi level, benefiting the generation of *COOH key intermediate as well as the desorption of *CO and hence leading to significantly boosted activity and selectivity for CO2-to-CO photoreduction.

2.
J Anim Sci Biotechnol ; 15(1): 134, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39370514

RESUMO

BACKGROUND: Oxidative stress significantly impacts growth performance and liver function in piglets. Ferulic acid (FA) works as an antioxidant, however, the role and mechanism of FA in the regulation of diquat-induced oxidative stress in piglets are less known. This study was designed to investigate the effects of FA on growth performance and antioxidant capacity in piglets with diquat challenge. METHODS: Thirty-two healthy DLY (Duroc × Landrace × Yorkshire) piglets (13.24 ± 0.19 kg) were randomly divided into one of two diets including 0 or 4 g/kg FA for 14 d. On d 15, all pigs were intraperitoneally injected diquat or sterile saline. RESULTS: Dietary supplementation with ferulic acid (FA) significantly improved the average daily gain (ADG) and decreased feed-gain ratio (F/G) of piglets. Here, dietary FA supplementation reduced serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) activities in diquat challenged piglets. Furthermore, diquat infusion increased reactive oxygen radicals (ROS) level in liver, decreased the activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC) and increased malondialdehyde (MDA) content in the liver and serum. Supplementation with FA significantly increased T-AOC and T-SOD activities and decreased MDA and ROS levels. FA down-regulated gene and protein expression of Keap1, and up-regulated protein expression of Nrf2 and HO-1 in the liver of piglets with diquat challenge. Importantly, diquat challenge increased the ratio of late apoptosis, increased serum levels of IL-1ß, IL-18 and lactate dehydrogenase (LDH), and up-regulated pyroptosis-related genes in the liver. FA supplementation reduced the ratio of late apoptosis and down-regulated mRNA expression of Caspase-1. Accordingly, FA addition reduced concentration of IL-1ß, IL-18, and LDH under diquat challenge. CONCLUSIONS: Diquat-induced oxidative stress reduced growth performance and impaired liver function in piglets. Dietary FA supplementation enhanced the antioxidant capacity and reduced the degree of hepatocyte pyroptosis, thereby alleviating the oxidative damage in the liver and mitigating the impact of diquat on growth performance of piglets.

3.
Nano Lett ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373390

RESUMO

Domain orientation modulation and controlled doping of two-dimensional (2D) transition-metal dichalcogenides (TMDCs) are two pivotal tasks for synthesizing wafer-scale single crystals and boosting device performances. However, realizing two such targets and uncovering internal physical mechanisms remain daunting challenges. We develop an accurate Fe doping strategy, which enables domain orientation control and electron mobility improvement of monolayer MoS2. By tuning of the Fe dopant dosages, parallel steps with different heights are formed, which induce edge-nucleation of unidirectionally aligned monolayer MoS2. In parallel, Fe doping induces the down shift of the conduction band minimum of monolayer MoS2 and matches well with the work function of an electrode, which reduces Schottky barrier height and delivers ultralow contact resistance (561 Ω µm) and excellent electron mobility (37.5 cm2 V-1 s-1). The modulation mechanism is clarified by combining theory calculations and electronic structure characterizations. This work hereby provides a new paradigm for synthesizing wafer-scale 2D TMDC single crystals and constructing high-performance devices.

4.
Phytother Res ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39417325

RESUMO

Pulmonary fibrosis (PF) is a lethal disease caused by inordinate repair of damaged lungs, for which limited strategies are available. Polyphyllin VI (PPVI), extracted and isolated from Paris polyphylla Smith var. chinensis (Franch.) Hara, has been regarded as an important traditional Chinese herbal medicine for the treatment of respiratory system diseases. This study evaluated effects of PPVI on PF and its underlying mechanism. Experimental procedure For evaluating the anti-PF effect of PPVI, we established an in vivo PF mouse model via intratracheal infusion of bleomycin (BLM) in mice and an in vitro PF model induced by TGF-ß1 in NIH/3T3, HPF and A549, respectively. Subsequently, the mechanism of PPVI effects was further explored using RNA sequencing (RNA-Seq). The in vivo and in vitro results demonstrated that PPVI significantly inhibited inflammation, oxidative damage, and epithelial-mesenchymal transition. Furthermore, RNA sequencing indicated that PPVI ameliorated PF by modulating inflammation and oxidative stress responses. Furthermore, dual specificity phosphatase 6 (DUSP6), was the shared and most significant differentially expressed gene associated with inflammation and oxidative stress response after PPVI treatment. Mechanistically, silencing DUSP6 can eliminate the suppressive impact on PPVI for the activation of fibroblast and the phosphorylation of ERK and AKT. Summarily, our findings revealed the potential of PPVI in mitigating PF via upregulating DUSP6 and highlighted the regulatory function of DUSP6 in the pathogenesis of PF.

5.
Global Spine J ; : 21925682241293712, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39407406

RESUMO

STUDY DESIGN: Machine learning model. OBJECTIVES: This study aimed to develop and validate a machine learning (ML) model to predict moderate-severe anterior bone loss (ABL) following anterior cervical disc replacement (ACDR). METHODS: A retrospective review of patients undergoing ACDR or Hybrid surgery (HS) at a single center was performed. Patients diagnosed as C3-7 single- or multi-level cervical disc degenerative diseases (CDDD) with more than 2 years of follow-up and complete pre- and postoperative radiological imaging were included. An ML-based algorithm was developed to predict moderate-severe ABL based on perioperative demographic, clinical, and radiographic parameters. Model performance was evaluated in terms of discrimination and overall performance. RESULTS: A total of 339 ACDR segments were included (61.65% female, mean age 45.65 ± 8.03 years). During a follow-up period of 45.65 ± 8.03 months, 103 (30.38%) segments developed moderate-severe ABL. The model demonstrated good discrimination and overall performance according to precision (moderate-severe ABL: 0.71 ± 0.07, none-mild ABL: 0.73 ± 0.08), recall (moderate-severe ABL: 0.69 ± 0.08, none-mild ABL: 0.75 ± 0.07), F1-score (moderate-severe ABL: 0.70 ± 0.08, none-mild ABL: 0.74 ± 0.07), and area under the curve (AUC) (0.74 ± 0.10). The most important predictive features were higher height change, higher post-segmental angle, and longer operation time. CONCLUSIONS: Utilizing a ML approach, this study successfully identified risk factors and accurately predicted the development of moderate-severe ABL following ACDR, demonstrating robust discrimination and overall performance. By overcoming the limitations of traditional statistical methods, ML can enhance discovery, clinical decision-making, and intraoperative techniques.

6.
J Steroid Biochem Mol Biol ; 245: 106626, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39448042

RESUMO

Polycystic ovary syndrome (PCOS) is a metabolic disorder with clinical heterogeneity. PCOS women with non-hyperandrogenemia (NA) might be misdiagnosed due to a lack of diagnostic markers. This study aims to systematically analyze the differences in steroid hormones between PCOS women with hyperandrogenemia (HA) and NA, and to screen classification diagnosis models for PCOS. The serum samples from 54 HA-PCOS, 79 NA-PCOS and 60 control women (Non-PCOS) aged between 18 and 35 were measured by an integrated steroid hormone-targeted quantification assay using LC-MS/MS. The levels of serum androgens, corticosteroids, progestins and estrogens in the steroid hormone biosynthesis pathway were analyzed in PCOS and Non-PCOS women. Eight machine learning methods including Linear Discriminant Analysis (LDA), K-nearest Neighbors (KNN), Boosted Logistic Regression (LogitBoost), Naive Bayes (NB), C5.0 algorithm (C5), Random Forest (RF), Support Vector Machines (SVM), and Neural Network (NNET) were performed, evaluated and selected for classification diagnosis of PCOS. A 10-fold cross-validation on the training set was performed. The whole metabolic flux from cholesterol to downstream steroid hormones increased significantly in PCOS, especially in HA-POCS women. The RF model was chosen for the classification diagnosis of HA-PCOS, NA-PCOS, and Non-PCOS women due to the maximum average accuracy (0.938, p<0.001), AUC (0.989, p<0.001), and kappa (0.906, p<0.001), and the minimum logLoss (0.200, p<0.001). Five steroid hormones including testosterone, androstenedione, total 2-methoxyestradiol, total 4-methoxyestradiol, and free estrone were selected as the decision trees for the simplified RF model. A total of 37 women were included in the validation set. The diagnostic sensitivity for HA-PCOS, NA-PCOS, and Non-PCOS was 100 %, 93.3 % and 91.7 %, respectively. HA-PCOS, NA-PCOS, and Non-PCOS women showed obvious different steroid hormone profiles. The simplified RF model based on two androgens and three estrogens could be effectively applied to the classification diagnosis of PCOS, further reducing the missed diagnosis rate of NA-PCOS.

7.
Nat Commun ; 15(1): 9166, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39448563

RESUMO

Vestibular hair cells are mechanoreceptors critical for detecting head position and motion. In mammals, hair cell loss causes vestibular dysfunction as spontaneous regeneration is nearly absent. Constitutive expression of exogenous ATOH1, a hair cell transcription factor, increases hair cell regeneration, however, these cells fail to fully mature. Here, we profiled mouse utricles at 14 time points, and defined transcriptomes of developing and mature vestibular hair cells. To mimic native hair cells which downregulate endogenous ATOH1 as they mature, we engineered viral vectors carrying the supporting cell promoters GFAP and RLBP1. In utricles damaged ex vivo, both CMV-ATOH1 and GFAP-ATOH1 increased regeneration more effectively than RLBP1-ATOH1, while GFAP-ATOH1 and RLBP1-ATOH1 induced hair cells with more mature transcriptomes. In utricles damaged in vivo, GFAP-ATOH1 induced regeneration of hair cells expressing genes indicative of maturing type II hair cells, and more hair cells with bundles and synapses than untreated organs. Together our results demonstrate the efficacy of spatiotemporal control of ATOH1 overexpression in inner ear hair cell regeneration.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Células Ciliadas Vestibulares , Regeneração , Sáculo e Utrículo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Camundongos , Sáculo e Utrículo/metabolismo , Regeneração/genética , Células Ciliadas Vestibulares/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Proteína Glial Fibrilar Ácida/genética , Transcriptoma/genética , Regiões Promotoras Genéticas/genética , Masculino
10.
Front Vet Sci ; 11: 1430696, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39351150

RESUMO

Introduction: Benzoic acid (BA) could be added to the diets of weaned pigs to prevent diarrhea due to its antibacterial function. However, BA may be absorbed or decomposed before it can reach the hindgut. This study was conducted to explore the effect of a novel coated benzoic acid (CBA) on growth performance, immunity, and intestinal barrier functions in weaned pigs upon enterotoxigenic Escherichia coli (ETEC) challenge. Methods: In a 21d experiment, 32 piglets were randomly assigned to 4 treatments: (1) a basal diet (CON), (2) CON added with CBA at 3 g/kg (CBA); (3) CON and challenged by ETEC (ECON); (4) CON added with CBA at 3 g/kg and challenged by ETEC (ECON). On d 22, all piglets were euthanised to obtain samples. Results: Dietary CBA supplementation elevated the average daily gain (ADG) of the ETEC-challenged pigs (p < 0.05). CBA also improved the digestibility of dry matter, gross energy, and ash (p < 0.05). Moreover, CBA elevated the ratio of blood basophil and the serum concentration of total cholesterol of the ETEC challenged pigs (p < 0.05). Importantly, CBA increased the serum concentrations of immunoglobulin A (IgA), IgG, and IgM (p < 0.05). CBA not only decreased the crypt depth but also increased the ratio of villus height to crypt depth (V:C) in the jejunum and ileum (p < 0.05). Moreover, CBA increased the activities of jejunal and ileal sucrase, and the activities of duodenal and ileal maltase (p < 0.05). Importantly, CBA elevated the expression levels of critical functional genes such as the claudin-1, occluding, glucose transporter-2 (GLUT2), and sodium/glucose cotransporter-1 (SGLT-1) in the jejunal epithelium upon ETEC challenge (p < 0.05). Additionally, CBA increased the abundances of total bacteria and Bacillus, and increased the concentrations of volatile fatty acids (acetic acid, propanoic acid, and butyric acid) in cecum (p < 0.05). Discussion: These results suggested a beneficial role for CBA in alleviating intestinal injury in weaned pigs following ETEC challenge. Such effects may be tightly associated with elevated immunity and improved intestinal epithelium functions and microbiota.

11.
J Immunol ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400236

RESUMO

Hepatitis B virus (HBV) is the most common chronic viral infection globally, affecting ∼360 million people and causing about 1 million deaths annually due to end-stage liver disease or hepatocellular carcinoma. Current antiviral treatments rarely achieve a functional cure for chronic hepatitis B, highlighting the need for improved monitoring and intervention strategies. This study explores the role of the sphingosine kinase 1 (SphK1)-sphingosine-1-phosphate (S1P) axis in HBV-related liver injury. We investigated the association between serum S1P concentration and HBV DNA levels in chronic hepatitis B patients, finding a significant positive correlation. Additionally, SphK1 was elevated in liver tissues of HBV-positive hepatocellular carcinoma patients, particularly in HBsAg-positive regions. HBV infection models in HepG2-sodium taurocholate cotransporting polypeptide cells confirmed that HBV enhances SphK1 expression and S1P production. Inhibition of HBV replication through antiviral agents and the CRISPR-Cas9 system reduced SphK1 and S1P levels. Further, we identified the transcription factor USF1 as a key regulator of SphK1 expression during HBV infection. USF1 binds to the SphK1 promoter, increasing its transcriptional activity, and is upregulated in response to HBV infection. In vivo studies in mice demonstrated that HBV exposure promotes the expression of USF1 and SphK1-S1P. These findings suggest that the SphK1-S1P axis, regulated by HBV-induced USF1, could serve as a potential biomarker and therapeutic target for HBV-related liver injury.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39444345

RESUMO

Tim-1 (T-cell immunoglobulin and mucin domain 1), also known as Kim-1 (kidney injury molecule 1) or hepatitis A virus cellular receptor 1 (HAVCR1), is a transmembrane protein expressed on various immune and epithelial cells. It plays a role in modulating inflammatory and immune responses. In this study, we find that Tim-1 is overexpressed in hepatocellular carcinoma (HCC) samples and that its expression is significantly correlated with postoperative survival. Bulk RNA sequencing reveals a general upregulation of extracellular matrix-related genes in HCC tissues with Tim-1 overexpression. The results of the cell and in vivo experiments reveal that Tim-1 in HCC not only affects biological processes such as the proliferation, migration, and invasion of HCC cells but also broadly promotes extracellular matrix processes by influencing cytokine secretion. Further studies demonstrate that Tim-1 mediates the activation of hepatic stellate cells and upregulates Th1 and Th2 cytokines, thereby promoting HCC progression. Thus, Tim-1 may represent a novel target for future interventions in HCC and liver fibrosis.

13.
Int J Mol Sci ; 25(19)2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39408794

RESUMO

Radiation is a mainstay of lung cancer treatment; however, resistance frequently develops. Identifying novel therapeutic targets to increase radiation sensitivity is crucial. S6K1 is a serine/threonine kinase known to regulate protein translation which is associated with radioresistance, but the mechanisms involved are unknown. We proposed to determine whether S6K1 promotes radioresistance by regulating DNA repair in lung cancer. Colony formation, protein expression and proliferation were assessed. S6K1 was modulated pharmacologically by either PF-4708671 or genetically by Crispr-Cas9. Higher radioresistance levels in lung cancer cells were associated with lower phosphoactivation of MRN complex members, a key activator of radiation-induced DNA repair signaling. We also found lower levels of p-ATM, a target of the MRN complex, in more radioresistant cells, which was associated with a lower expression of γ-H2AX cafter radiation. Further, genetic and pharmacological S6K1 targeting sensitized lung cancer cells to low doses of radiation (p ≤ 0.01). Additionally, S6K1-/- deletion increased the phosphoactivation of MRN complex members, indicating that S6K1 itself can shut down DNA damage regulated by MRN signaling. This is the first report showing that S6K1 inhibition radiosensitizes lung cancer cells by decreasing MRN complex-regulated DNA repair signaling. Future studies should evaluate the role of S6K1 as a target to overcome radioresistance.


Assuntos
Dano ao DNA , Reparo do DNA , Neoplasias Pulmonares , Proteína Homóloga a MRE11 , Tolerância a Radiação , Transdução de Sinais , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Tolerância a Radiação/genética , Linhagem Celular Tumoral , Proteína Homóloga a MRE11/metabolismo , Proteína Homóloga a MRE11/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , Hidrolases Anidrido Ácido/metabolismo , Hidrolases Anidrido Ácido/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Enzimas Reparadoras do DNA/genética , Histonas/metabolismo , Fosforilação , Animais , Proliferação de Células , Camundongos
14.
Nat Commun ; 15(1): 9269, 2024 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-39465277

RESUMO

Sir2-HerA is a widely distributed antiphage system composed of a RecA-like ATPase (HerA) and an effector with potential NADase activity (Sir2). Sir2-HerA is believed to provide defense against phage infection in Sir2-dependent NAD+ depletion to arrest the growth of infected cells. However, the detailed mechanism underlying its antiphage activity remains largely unknown. Here, we report functional investigations of Sir2-HerA from Staphylococcus aureus (SaSir2-HerA), unveiling that the NADase function of SaSir2 can be allosterically activated by the binding of SaHerA, which then assembles into a supramolecular complex with NADase activity. By combining the cryo-EM structure of SaSir2-HerA in complex with the NAD+ cleavage product, it is surprisingly observed that Sir2 protomers that interact with HerA are in the activated state, which is due to the opening of the α15-helix covering the active site, allowing NAD+ to access the catalytic pocket for hydrolysis. In brief, our study provides a comprehensive view of an allosteric activation mechanism for Sir2 NADase activity in the Sir2-HerA immune system.


Assuntos
Proteínas de Bactérias , Microscopia Crioeletrônica , NAD , Staphylococcus aureus , Regulação Alostérica , NAD/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , NAD+ Nucleosidase/metabolismo , NAD+ Nucleosidase/química , Modelos Moleculares , Ligação Proteica , Domínio Catalítico , Bacteriófagos/metabolismo
15.
Ying Yong Sheng Tai Xue Bao ; 35(8): 2247-2255, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39419810

RESUMO

Anthropogenic hydrological regulation is profoundly altering the structure and function of wetland ecosystems. Due to the scarcity of long-term monitoring records, the responses of wetland ecosystems to anthropogenic hydrological regulation remain unclear. We reconstructed past ecohydrological changes in Dajiuhu Wetland during the last 40 years and explored the driving forces, based on multiproxy records of a 44-cm-length sediment core collected from Wuhaohu Lake of Dajiuhu Wetland in Shennongjia, Hubei. The results showed that the diatom community in Wuhaohu Lake had experienced three major stages, including the dominance of benthic diatoms between 1980 and 2008, the rapid increase in planktonic diatoms between 2008 and 2016, and the dominance of small-sized fragilarioid species after 2016. Results of redundancy analysis showed that change in diatom assemblage was significantly correlated with total organic carbon, total nitrogen and the ratios of Mn to Fe. Diatom floral changes after 2008 indicated the shift of Wuhaohu Lake from an early organic-rich peatland to a shallow lake, mainly in response to an increase in water table driven by damming. From 2016, the increases in benthic and epiphytic diatoms responded to the expansion of aquatic plants and improved light penetration after the relocation of local population. Sedimentary diatom records revealed the process of environmental changes, and hence would provide a scientific basis for the environmental protection of wetlands.


Assuntos
Diatomáceas , Monitoramento Ambiental , Sedimentos Geológicos , Áreas Alagadas , Diatomáceas/crescimento & desenvolvimento , China , Sedimentos Geológicos/química , Sedimentos Geológicos/análise , Ecossistema , Lagos , Nitrogênio/análise
16.
Microbiol Spectr ; : e0127624, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39404351

RESUMO

This study aimed to explore the effect of cyclosporine (CsA) on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in systemic lupus erythematosus (SLE) patients to provide a valuable reference for clinical treatment strategies in the context of the long-term risk of SARS-CoV-2 infection. SLE patients who visited the Rheumatology Outpatient Department of Fujian Medical University Union Hospital between 1 May and 31 October 2022 were included. Data on SARS-CoV-2 infection in patients between 1 November 2022 and 31 July 2023 were obtained by telephone follow-up. Patients were divided into two groups according to whether CsA was used during the observation period: the glucocorticoid or hydroxychloroquine group and the CsA group. To assess the robustness of the results, Data sets 1 and 2 were established to be analyzed independently. Multivariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for symptomatic coronavirus disease (COVID-19). A total of 184 patients were included, among whom 129 were definite symptomatic COVID-19 patients; 29 were presumptive symptomatic COVID-19 patients; and 4 had signs and symptoms of COVID-19, but tested negative for SARS-CoV-2 in a virological test. According to the multivariable-adjusted models, CsA was associated with lower odds of symptomatic COVID-19 (P = 0.042, OR = 0.316, 95% CI: 0.104-0.959 in Data set 1 and P = 0.021, OR = 0.257, 95% CI: 0.081-0.812 in Data set 2). CsA is associated with lower odds of contracting symptomatic COVID-19. The use of CsA may be considered an appropriate therapeutic option for disease management in patients with rheumatic diseases who have severe disease activity and persistent SARS-CoV-2 infection. IMPORTANCE: Our study indicated that cyclosporine may reduce the risk of symptomatic COVID-19 in systemic lupus erythematosus patients in spite of its immunosuppressive effects. This study provides a reference for clinical treatment strategies for AIIRD patients in the context of the long-term risk of SARS-CoV-2 infection.

18.
Biochemistry ; 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39475147

RESUMO

Cyclodipeptide synthases (CDPSs) catalyze the synthesis of diverse cyclodipeptides (CDPs) by utilizing two aminoacyl-tRNA (aa-tRNA) substrates in a sequential ping-pong reaction mechanism. Numerous CDPSs have been characterized to provide precursors for diketopiperazines (DKPs) with diverse structural characteristics and biological activities. BcmA, belonging to the XYP subfamily, is a cyclo(l-Ile-l-Leu)-synthesizing CDPS involved in the biosynthesis of the antibiotic bicyclomycin. The structural basis and determinants influencing BcmA enzyme activity and substrate selectivity are not well understood. Here, we report the crystal structure of SsBcmA from Streptomyces sapporonensis. Through structural comparison and systematic site-directed mutagenesis, we highlight the significance of key residues located in the aminoacyl-binding pocket for enzyme activity and substrate specificity. In particular, the nonconserved residues D161 and K165 in pocket P2 are essential for the activity of SsBcmA without significant alteration of the substrate specificity, while the conserved residues F158 as well as F210 and S211 in P2 are responsible for determining substrate selectivity. These findings facilitate the understanding of how CDPSs selectively accept hydrophobic substrates and provide additional clues for the engineering of these enzymes for synthetic biology applications.

19.
Discov Oncol ; 15(1): 560, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39404967

RESUMO

Pancreatic cancer is among the most immune-resistant tumor types due to its unique tumor microenvironment and low cancer immunogenicity. Single-agent immune modulators have thus far proven clinically ineffective. However, a growing body of evidence suggests that combination of these modulators with other strategies could unlock the potential of immunotherapy in pancreatic cancer. Herein, we describe the case of a 59-year-old male with metastatic pancreatic ductal adenocarcinoma, referred to our center to receive immunotherapy (serplulimab, a novel anti-PD-1 antibody) combined with chemotherapy (gemcitabine/nab-paclitaxel). During the initial three treatment cycles, the patient was assessed as having stable disease (SD) according to RECIST 1.1 criteria. However, following two additional cycles of combination therapy, the primary tumor mass increased from 4.9 cm to 13.2 cm, accompanied by the development of new lung lesions, ascites, and pelvic metastases. He succumbed to respiratory failure one month later. Retrospective analysis revealed that the patient had MDM4 amplification, identified as a high-risk factor for hyperprogressive disease (HPD). To our knowledge, this is the first reported case of HPD in pancreatic cancer with multiple metastases treated using combination therapy. We investigated the potential mechanisms and reviewed the latest literature on predictive factors for HPD. These findings suggest that while chemotherapy combined with immunotherapy may hold promise for treating pancreatic cancer, it is imperative to identify and closely monitor patients with high-risk factors for HPD when using immunotherapy.

20.
J Crit Care ; 85: 154932, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-39432929

RESUMO

BACKGROUND: Septic shock (SS) is a highly fatal and heterogeneous syndrome. Identifying distinct clinical phenotypes provides valuable insights into the underlying pathophysiological mechanisms and may help to propose precise clinical management strategies. METHODS: Latent profile analysis (LPA), a model-based unsupervised method, was used for phenotyping in the MIMIC cohort, and the model was externally independently validated in the eICU and AUMC cohorts. RESULTS: Three phenotypes, labeled phenotype I, II, and III, were derived. These phenotypes varied in demographics, clinical features, comorbidities, patterns of organ dysfunction, organ support, and prognosis. Phenotype I, characterized by the most severe organ dysfunction (especially liver), the youngest age, and the highest BMI, had the highest mortality (p < 0.001). Phenotype II, with moderate mortality, was characterized by severe renal injury. In contrast, phenotype III, associated with the oldest age and the fewest comorbidities, exhibited significantly lower mortality. Phenotype I patients had the steepest survival curves and demonstrated an ultra-high risk of death, particularly within the first few days after SS onset. CONCLUSIONS: The individualized identification of phenotypes is well suited to clinical practice. The three SS phenotypes differed significantly in pathophysiological and clinical outcomes, which are crucial for informing management decisions and prognosis.

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