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1.
Brief Bioinform ; 25(4)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38960407

RESUMO

The optimization of therapeutic antibodies through traditional techniques, such as candidate screening via hybridoma or phage display, is resource-intensive and time-consuming. In recent years, computational and artificial intelligence-based methods have been actively developed to accelerate and improve the development of therapeutic antibodies. In this study, we developed an end-to-end sequence-based deep learning model, termed AttABseq, for the predictions of the antigen-antibody binding affinity changes connected with antibody mutations. AttABseq is a highly efficient and generic attention-based model by utilizing diverse antigen-antibody complex sequences as the input to predict the binding affinity changes of residue mutations. The assessment on the three benchmark datasets illustrates that AttABseq is 120% more accurate than other sequence-based models in terms of the Pearson correlation coefficient between the predicted and experimental binding affinity changes. Moreover, AttABseq also either outperforms or competes favorably with the structure-based approaches. Furthermore, AttABseq consistently demonstrates robust predictive capabilities across a diverse array of conditions, underscoring its remarkable capacity for generalization across a wide spectrum of antigen-antibody complexes. It imposes no constraints on the quantity of altered residues, rendering it particularly applicable in scenarios where crystallographic structures remain unavailable. The attention-based interpretability analysis indicates that the causal effects of point mutations on antibody-antigen binding affinity changes can be visualized at the residue level, which might assist automated antibody sequence optimization. We believe that AttABseq provides a fiercely competitive answer to therapeutic antibody optimization.


Assuntos
Complexo Antígeno-Anticorpo , Aprendizado Profundo , Complexo Antígeno-Anticorpo/química , Antígenos/química , Antígenos/genética , Antígenos/metabolismo , Antígenos/imunologia , Afinidade de Anticorpos , Sequência de Aminoácidos , Biologia Computacional/métodos , Humanos , Mutação , Anticorpos/química , Anticorpos/imunologia , Anticorpos/genética , Anticorpos/metabolismo
2.
Cell Mol Life Sci ; 81(1): 28, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38212428

RESUMO

Although amplifications and mutations in receptor tyrosine kinases (RTKs) act as bona fide oncogenes, in most cancers, RTKs maintain moderate expression and remain wild-type. Consequently, cognate ligands control many facets of tumorigenesis, including resistance to anti-RTK therapies. Herein, we show that the ligands for the RTKs MET and RON, HGF and HGFL, respectively, are synthesized as inactive precursors that are activated by cellular proteases. Our newly generated HGF/HGFL protease inhibitors could overcome both de novo and acquired cetuximab resistance in colorectal cancer (CRC). Conversely, HGF overexpression was necessary and sufficient to induce cetuximab resistance and loss of polarity. Moreover, HGF-induced cetuximab resistance could be overcome by the downstream MET inhibitor, crizotinib, and upstream protease inhibitors. Additionally, HAI-1, an endogenous inhibitor of HGF proteases, (i) was downregulated in CRC, (ii) exhibited increased genomic methylation that correlated with poor prognosis, (iii) HAI-1 expression correlated with cetuximab response in a panel of cancer cell lines, and (iv) exogenous addition of recombinant HAI-1 overcame cetuximab resistance in CC-HGF cells. Thus, we describe a targetable, autocrine HAI-1/Protease/HGF/MET axis in cetuximab resistance in CRC.


Assuntos
Neoplasias Colorretais , Transdução de Sinais , Humanos , Cetuximab/farmacologia , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Inibidores de Proteases/farmacologia , Peptídeo Hidrolases/metabolismo , Linhagem Celular Tumoral , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Fator de Crescimento de Hepatócito/farmacologia
3.
Chem Res Toxicol ; 37(4): 658-668, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38525689

RESUMO

Exposure to triclocarban (TCC), a commonly used antibacterial agent, has been shown to induce significant intestine injuries and colonic inflammation in mice. However, the detailed mechanisms by which TCC exposure triggered enterotoxicity remain largely unclear. Herein, intestinal toxicity effects of long-term and chronic TCC exposure were investigated using a combination of histopathological assessments, metagenomics, targeted metabolomics, and biological assays. Mechanically, TCC exposure caused induction of intestinal aryl hydrocarbon receptor (AhR) and its transcriptional target cytochrome P4501A1 (Cyp1a1) leading to dysfunction of the gut barrier and disruption of the gut microbial community. A large number of lipopolysaccharides (LPS) are released from the gut lumen into blood circulation owing to the markedly increased permeability and gut leakage. Consequently, toll-like receptor-4 (TLR4) and NF-κB signaling pathways were activated by high levels of LPS. Simultaneously, classic macrophage phenotypes were switched by TCC, shown with marked upregulation of macrophage M1 and downregulation of macrophage M2 that was accompanied by striking upregulation of proinflammatory factors such as Il-1ß, Il-6, Il-17, and Tnf-α in the intestinal lamina propria. These findings provide new evidence for the TCC-induced enterotoxicity.


Assuntos
Carbanilidas , Lipopolissacarídeos , Receptores de Hidrocarboneto Arílico , Camundongos , Animais , Receptores de Hidrocarboneto Arílico/metabolismo , Lipopolissacarídeos/toxicidade , NF-kappa B/metabolismo , Inflamação/metabolismo
4.
Pharmacol Res ; 200: 107060, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38185210

RESUMO

OBJECTIVE: To assess the efficacy and safety of FDA-approved KRASG12C inhibitors in patients with KRASG12C-mutated solid tumors. METHODS: We searched PubMed, EMBASE, Cochrane Library, and major international conferences for clinical trials published in English up to March 6, 2023. Clinical trials investigating sotorasib or adagrasib and reporting the clinical outcomes of the objective response rate (ORR), disease control rate (DCR), or incidence rate of grade ≥ 3 adverse events (AEs) were eligible. The primary endpoint was the ORR. Secondary endpoints included the DCR, incidence rate of grade ≥ 3 AEs, and odds ratio (OR) of the ORR between patients with or without co-mutation. The Random-effects model was applied for the outcomes of interest. RESULTS: 18 studies with 1224 patients were included in this meta-analysis. The pooled ORR, DCR, and incidence rate of grade ≥ 3 AEs were 31 % (95 % CI, 25-37 %), 86 % (95 % CI, 82-89 %), and 29 % (95 % CI, 23-36 %), respectively. KRASG12C-mutated NSCLC patients with a co-mutation of KEAP1 exhibited a worse ORR than those with wild-type KEAP1 (OR: 0.35, 95 % CI: 0.16-0.77). CONCLUSIONS: This study provided a comprehensive understanding of the efficacy and safety of KRASG12C inhibitors in treating solid tumors and identified KEAP1 mutation as a potential predictive biomarker of inferior response in patients treated with KRASG12C inhibitors. These findings may assist in the design of future clinical trials for identifying populations that may benefit from KRASG12C inhibitor treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch , Proteínas Proto-Oncogênicas p21(ras) , Fator 2 Relacionado a NF-E2 , Mutação
5.
Clin Exp Rheumatol ; 42(2): 237-245, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38153165

RESUMO

OBJECTIVES: Anti-MDA5+ dermatomyositis was associated with poor prognosis due to the high incidence of rapid progressive interstitial lung disease, pulmonary infection. The aim of this study is to investigate the abundance and clinical relevance of exhaustion markers on peripheral CD8 T cells from patients with idiopathic inflammatory myopathy (IIM). METHODS: Twenty-nine healthy controls (HCs) and 71 patients with IIM were enrolled, including 42 with anti-MDA5+ and 18 with anti-MDA5- dermatomyositis (DM) and 11 with anti-synthetase syndrome (ASS). Flow cytometry was applied to detect PD-1, TIM-3 and LAG-3 in CD8 T cells. The clinical associations of the CD8 T cell exhaustion phenotype in patients with anti-MDA5+ DM were analysed. RESULTS: CD8 T cells from patients with anti-MDA5+ DM showed significantly increased LAG-3, TIM-3 and PD-1 compared to those from patients with anti-MDA5- IIM (18 with anti-MDA5- DM and 11 with ASS) or HCs (adjusted p all < 0.05). CD8 T cells with distinct exhaustion levels were all significantly increased in anti-MDA5+ DM patients compared with HCs (p all < 0.05). Patients with high level of PD-1+ TIM-3+LAG-3+ CD8+ T cells had a significant higher incidence of pulmonary fungal infections but lower counts of CD4+ and CD8+ T cells. ROC analysis revealed that the frequency of PD-1+TIM-3+LAG-3+CD8+ T cell significantly predicted pulmonary fungal infections (area under the curve: 0.828). CONCLUSIONS: CD8 T cells from patients with anti-MDA5+ DM show significant exhausted phenotype, and increased exhausted CD8 T cells were associated with high risk of pulmonary fungal infection.


Assuntos
Dermatomiosite , Humanos , Dermatomiosite/complicações , Receptor Celular 2 do Vírus da Hepatite A , Helicase IFIH1 Induzida por Interferon , Receptor de Morte Celular Programada 1 , Autoanticorpos , Linfócitos T CD8-Positivos , Linfócitos T , Estudos Retrospectivos , Prognóstico
6.
BMC Psychiatry ; 24(1): 129, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365642

RESUMO

BACKGROUND: Growing evidence suggested that particulate matter (PM) exhibit an increased risk of autism spectrum disorder (ASD). However, the causal association between PM and ASD risk remains unclear. METHODS: We performed two-sample Mendelian randomization (MR) analyses, using instrumental variables (IVs) sourced from the largest genome-wide association studies (GWAS) databases. We employed three MR methods: inverse-variance weighted (IVW), weighted median (WM), and MR-Egger, with IVW method serving as our primary MR method. Sensitivity analyses were performed to ensure the stability of these findings. RESULTS: The MR results suggested that PM2.5 increased the genetic risk of ASD (ß = 2.41, OR = 11.13, 95% CI: 2.54-48.76, P < 0.01), and similar result was found for PM2.5 absorbance (ß = 1.54, OR = 4.67, 95% CI: 1.21-18.01, P = 0.03). However, no such association was found in PM10 (ß = 0.27, OR = 1.30, 95% CI: 0.72-2.36, P = 0.38). After adjusting for the false discovery rate (FDR) correction, our MR results remain consistent. Sensitivity analyses did not find significant heterogeneity or horizontal pleiotropy. CONCLUSIONS: Our findings indicate that PM2.5 is a potential risk factor for ASD. Effective strategies to mitigate air pollutants might lead to a reduced incidence of ASD.


Assuntos
Transtorno do Espectro Autista , Material Particulado , Humanos , Material Particulado/efeitos adversos , Transtorno do Espectro Autista/genética , Estudo de Associação Genômica Ampla , Fatores de Risco , Bases de Dados Factuais
7.
Sensors (Basel) ; 24(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38544158

RESUMO

Acoustic aberration, caused by the uneven distribution of tissue speed-of-sound (SoS), significantly reduces the quality of ultrasound imaging. An important approach to mitigate this issue is imaging correction based on local SoS estimation. Computed ultrasound tomography in echo mode (CUTE) is an SoS estimation method that utilizes phase-shift information from ultrasound pulse-echo signals, offering both practical utility and computational efficiency. However, the traditional single-pass CUTE often suffers from poor accuracy and robustness. In this paper, an advanced approach known as iterative CUTE is introduced, which refines SoS estimates through iterative correction of errors and noise, addressing the limitations of traditional single-pass methods. It is argued that traditional precision indicators like root mean square error (RMSE) fall short in adequately reflecting the quality of SoS estimates for imaging correction, and coherence factor (CF) is proposed as a more indicative metric. Performance validation of the iterative CUTE algorithm was conducted using a simulation and agar phantom experiment. The results indicated that the iterative CUTE approach surpasses the single-pass approach, enhancing the average CF for SoS estimates by up to 18.2%. In phantom experiments, imaging corrected with SoS estimates from iterative CUTE reduced the Array Performance Index (API) by up to 40% compared to traditional methods.

8.
J Clin Nurs ; 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38797951

RESUMO

OBJECTIVE: The objective of this study was to construct and validate a structural equation model (SEM) to identify factors associated with sleep quality in awake patients in the intensive care unit (ICU) and to assist in the development of clinical intervention strategies. RESEARCH METHODS/SETTING: In this cross-sectional study, 200 awake patients who were cared for in the ICU of a tertiary hospital in China were surveyed via several self-report questionnaires and wearable actigraphy sleep monitoring devices. Based on the collected data, structural equation modelling analysis was performed using SPSS and AMOS statistical analysis software. The study is reported using the STROBE checklist. RESULTS: The fit indices of the SEM were acceptable: χ2/df = 1.676 (p < .001) and RMSEA = .058 (p < 0.080). Anxiety/depression had a direct negative effect on the sleep quality of awake patients cared for in the ICU (ß = -.440, p < .001). In addition, disease-freeness progress had an indirect negative effect on the sleep quality of awake patients cared for in the ICU (ß = -.142, p < .001). Analgesics had an indirect negative effect on the sleep quality of awake patients cared for in the ICU through pain and sedatives (ß = -.082, p < .001). Sedation had a direct positive effect on the sleep quality of conscious patients cared for in the ICU (ß = .493; p < .001). CONCLUSION: The results of the SEM showed that the sleep quality of awake patients cared for in the ICU is mainly affected by psychological and disease-related factors, especially anxiety, depression and pain, so we can improve the sleep quality of patients through psychological intervention and drug intervention.

9.
Int Orthop ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012414

RESUMO

PURPOSE: Robot-assisted total hip arthroplasty (RA-THA) helps with precise orientation of the prosthesis, but some RA-THA procedures are aborted intraoperatively and are converted to manual total hip arthroplasty (THA). This study aimed to analyse why RA-THA is sometimes aborted intraoperatively and to make recommendations accordingly. METHODS: A total of 429 consecutive Mako THA cases in our prospective database from August 2018 to June 2021 were included in our study. All robotic procedures aborted intraoperatively for any reason were recorded. The patients' demographics, diagnoses, and surgeons' information were included in the statistical analysis to pinpoint the risk factors for intraoperative robot to manual conversion. RESULTS: Intraoperative RA-THA abortions occurred in 17 cases (3.96%) and the patients had to be converted to manual THA. The adverse events leading to intraoperative abortions included pelvic array loosening or malposition (5, 1.17%), inaccurate bone mapping or construction (6, 1.40%), inaccurate initial registration (4, 0.93%), and other reasons (2, 0.47%). CONCLUSION: Robot-related adverse events could be found in all perioperative steps of RA-THA, and some of these events might result in intraoperative abortion. Complex hip disease was a statistically significant factor for an increased risk of intraoperative abortion of RA-THA. Standardized surgical procedures and preoperative assessments can be helpful in reducing the rate of RA-THA abortions.

10.
Int J Mol Sci ; 25(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38612682

RESUMO

Squalene epoxidase (SQLE) is a key enzyme in the mevalonate-cholesterol pathway that plays a critical role in cellular physiological processes. It converts squalene to 2,3-epoxysqualene and catalyzes the first oxygenation step in the pathway. Recently, intensive efforts have been made to extend the current knowledge of SQLE in cancers through functional and mechanistic studies. However, the underlying mechanisms and the role of SQLE in cancers have not been fully elucidated yet. In this review, we retrospected current knowledge of SQLE as a rate-limiting enzyme in the mevalonate-cholesterol pathway, while shedding light on its potential as a diagnostic and prognostic marker, and revealed its therapeutic values in cancers. We showed that SQLE is regulated at different levels and is involved in the crosstalk with iron-dependent cell death. Particularly, we systemically reviewed the research findings on the role of SQLE in different cancers. Finally, we discussed the therapeutic implications of SQLE inhibitors and summarized their potential clinical values. Overall, this review discussed the multifaceted mechanisms that involve SQLE to present a vivid panorama of SQLE in cancers.


Assuntos
Neoplasias , Esqualeno Mono-Oxigenase , Humanos , Morte Celular , Colesterol , Ácido Mevalônico , Neoplasias/genética , Esqualeno Mono-Oxigenase/genética
11.
Int J Mol Sci ; 25(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338920

RESUMO

Sarcomas are heterogeneous connective tissue malignancies that have been historically categorized into soft tissue and bone cancers. Although multimodal therapies are implemented, many sarcoma subtypes are still difficult to treat. Lipids play vital roles in cellular activities; however, ectopic levels of lipid metabolites have an impact on tumor recurrence, metastasis, and drug resistance. Thus, precision therapies targeting lipid metabolism in sarcoma need to be explored. In this study, we performed a comprehensive analysis of molecular stratification based on lipid metabolism-associated genes (LMAGs) using both public datasets and the data of patients in our cohort and constructed a novel prognostic model consisting of squalene epoxidase (SQLE) and tumor necrosis factor (TNF). We first integrated information on gene expression profile and survival outcomes to divide TCGA sarcoma patients into high- and low-risk subgroups and further revealed the prognosis value of the metabolic signature and immune infiltration of patients in both groups, thus proposing various therapeutic recommendations for sarcoma. We observed that the low-risk sarcoma patients in the TCGA-SARC cohort were characterized by high proportions of immune cells and increased expression of immune checkpoint genes. Subsequently, this lipid metabolic signature was validated in four external independent sarcoma datasets including the CHCAMS cohort. Notably, SQLE, a rate-limiting enzyme in cholesterol biosynthesis, was identified as a potential therapeutic target for sarcoma. Knockdown of SQLE substantially inhibited cell proliferation and colony formation while promoting the apoptosis of sarcoma cells. Terbinafine, an inhibitor of SQLE, displayed similar tumor suppression capacity in vitro. The prognostic predictive model and the potential drug target SQLE might serve as valuable hints for further in-depth biological, diagnostic, and therapeutic exploration of sarcoma.


Assuntos
Sarcoma , Transcriptoma , Humanos , Metabolismo dos Lipídeos/genética , Recidiva Local de Neoplasia , Sarcoma/tratamento farmacológico , Sarcoma/genética , Lipídeos
12.
Fetal Pediatr Pathol ; : 1-10, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39105619

RESUMO

OBJECTIVE: NeoBase 2 Non-derivatized MSMS assay kit (NeoBase 2 kit) was used for newborn screening, the performance of the NeoBase 2 kit should be validated before its implementation in clinical diagnostic laboratories. METHODS: Leftover dried blood spot samples, quality control materials in the NeoBase 2 kit, and proficiency testing materials received from the NSQAP were used. Precision, accuracy, LOD, LLOQ, recovery, and stability were carried out to verify the performance of the Waters ACQUITY TQD MS/MS system with the NeoBase 2 kit for newborn screening. Cutoffs were determined and analytes requiring different cutoffs in preterm neonates were investigated. RESULTS: Within-run and between-run precisions ranged from 3.95% to 14.41%. The accuracy and stability were within 15%. All analytes demonstrated acceptable LOD, LLOQ, and recoveries. Cutoffs for term and preterm neonates were established. CONCLUSIONS: The performance of the NeoBase 2 kit is acceptable and can be implemented in clinical diagnostic laboratories.

13.
Angew Chem Int Ed Engl ; : e202411236, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39045910

RESUMO

Visible light-driven photocatalytic deracemization is highly esteemed as an ideal tool for organic synthesis due to its exceptional atom economy and synthetic efficiency. Consequently, successful instances of deracemization of allenes have been established, where the activated energy of photosensitizer should surpass that of the substrates, representing an intrinsic requirement. Accordingly, this method is not applicable for axially chiral molecules with significantly high triplet energies. In this study, we present a photoredox catalytic deracemization approach that enables the efficient synthesis of valuable yet challenging-to-access axially chiral 2-azaarene-functionalized quinazolinones. The substrate scope is extensive, allowing for both 3-axis and unmet 1-axis assembly through facile oxidation of diverse central chiral 2,3-dihydroquinazolin-4(1H)-ones that can be easily prepared and achieve enantiomer enrichment via deracemization. Mechanistic studies reveal the importance of photosensitizer selection in attaining excellent chemoselectivity and highlight the indispensability of a chiral Brønsted acid in enabling highly enantioselective protonation to accomplish efficient deracemization.

14.
J Agric Food Chem ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38595054

RESUMO

Deoxynivalenol (DON) poses a serious global food safety risk due to its high toxicity and contamination rate. It disrupts the intestinal epithelial barrier, allowing exogenous toxins to enter the circulation and resulting in sepsis and systemic toxicity. In this research, 32 male Kunming mice and Porcine Small Intestinal Epithelial (IPEC-J2) cells were treated with DON at 0-4.8 mg/kg (7 d) and 0-12 µM (24 h), respectively. Histopathological results revealed that DON disrupted the intestinal epithelial barrier, causing apoptosis and tight junction (TJ) injury. Immunofluorescence and protein expression results showed that DON-induced p53-dependent mitochondrial pathway apoptosis and fibrillar actin (F-actin)-associated TJ injury and that the RhoA/ROCK pathway were activated in mice jejunal tissue and IPEC-J2 cells. Pretreatment with RhoA or ROCK inhibitors (Rosin or Y-27632) maintained DON-induced apoptosis and F-actin-associated TJ injury in IPEC-J2 cells. Thus, DON induces damage to the intestinal epithelial barrier through the RhoA/ROCK pathway-mediated apoptosis and F-actin-associated TJ disruption.

15.
Adv Mater ; : e2403116, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819929

RESUMO

Protein therapeutics offer high therapeutic potency and specificity; the broader adoptions and development of protein therapeutics, however, have been constricted by their intrinsic limitations such as inadequate stability, immunogenicity, suboptimal pharmacokinetics and biodistribution, and off-target effects. This review describes a platform technology that formulates individual protein molecules with a thin formulation layer of crosslinked polymers, which confers the protein therapeutics with high activity, enhanced stability, controlled release capability, reduced immunogenicity, improved pharmacokinetics and biodistribution, and ability to cross the blood brain barriers. Based on currently approved protein therapeutics, this formulating platform affords the development of a vast family of superior protein therapeutics with improved efficacy and broadened indications at significantly reduced cost.

16.
Foods ; 13(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38540811

RESUMO

To enhance the utilization of summer-autumn tea, a water-soluble polysaccharide (D1N1) was isolated through a series of techniques including hot water extraction, ethanol precipitation, and column chromatography. The structure of D1N1 was determined through the utilization of ultraviolet, Fourier-transform infrared, high-performance anion-exchange chromatography, gas chromatography-tandem mass spectrometry, and nuclear magnetic resonance. The results revealed that glucose was the predominant component of D1N1, accounting for 95% of its composition. Additionally, D1N1 also contained galactose, arabinose, and rhamnose. The molecular weight (Mw) of D1N1 was determined to be 224.71 kDa. The backbone of D1N1 consisted of →4)-α-D -Glcp (1→, →3,4)-α-D-Galp-(1→, →4,6)-α-D -Glcp (1→ at a molar ratio of 35:1:1, and branching at the O-3 position of →3,4)-α-D-Galp-(1→ and O-6 position of →4,6)-α-D-Glcp (1→ with α-D -Glcp (1→. In addition, the antioxidant activity of D1N1 was also evaluated. D1N1 exhibited excellent antioxidant bioactivity against the DPPH, superoxide anion radical, and ABTS+ radical. These findings provide a theoretical basis for the application of summer-autumn tea polysaccharide as a potential functional food.

17.
J Control Release ; 373: 216-223, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39002797

RESUMO

Platinum(II)-based drugs (PtII), which hinder DNA replication, are the most widely used chemotherapeutics. However, current PtII drugs often miss their DNA targets, leading to severe side effects and drug resistance. To overcome this challenge, we developed a oxaliplatin-based platinum(IV) (PtIV) prodrug amphiphile (C16-OPtIV-R8K), integrating a long-chain hydrophobic lipid and a nucleus-targeting hydrophilic peptide (R8K). This design allows the prodrug to self-assemble into highly uniform lipid nanoparticles (NTPtIV) for enhanced targeting chemotherapy and immunotherapy. Subsequently, NTPtIV's bioactivity and effects were examined at diverse levels, encompassing cancer cells, 3D tumor spheres, and in vivo. Our in vitro studies show a 74% cancer cell nucleus localization of platinum drugs-3.6 times higher than that of oxaliplatin, achieving more than a ten-fold increase in eliminating drug-resistant cancer cells. In vivo, NTPtIV shows efficient tumor accumulation, leading to suppressed tumor growth of murine breast cancer. Moreover, NTPtIV recruited more CD4+ and CD8+ T cells and reduced CD4+ Foxp3+ Tregs to synergistically enhance targeted chemotherapy and immunotherapy. Overall, this strategy presents a promising advancement in nucleus-targeted cancer therapy, synergistically boosting the efficacy of chemotherapy and immunotherapy.

18.
Biochim Biophys Acta Biomembr ; 1866(5): 184325, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38653423

RESUMO

Helical membrane proteins generally have a hydrophobic nature, with apolar side chains comprising the majority of the transmembrane (TM) helices. However, whenever polar side chains are present in the TM domain, they often exert a crucial role in structural interactions with other polar residues, such as TM helix associations and oligomerization. Moreover, polar residues in the TM region also often participate in protein functions, such as the Schiff base bonding between Lys residues and retinal in rhodopsin-like membrane proteins. Although many studies have focused on these functional polar residues, our understanding of stand-alone polar residues that are energetically unfavored in TM helixes is limited. Here, we adopted bacteriorhodopsin (bR) as a model system and systematically mutated 17 of its apolar Leu or Phe residues to polar Asn. Stability measurements of the resulting mutants revealed that all of these polar substitutions reduced bR stability to various extents, and the extent of destabilization of each mutant bR is also correlated to different structural factors, such as the relative accessible surface area and membrane depth of the mutation site. Structural analyses of these Asn residues revealed that they form sidechain-to-backbone hydrogen bonds that alleviate the unfavorable energetics in hydrophobic and apolar surroundings. Our results indicate that membrane proteins are able to accommodate certain stand-alone polar residues in the TM region without disrupting overall structures.


Assuntos
Bacteriorodopsinas , Interações Hidrofóbicas e Hidrofílicas , Estabilidade Proteica , Bacteriorodopsinas/química , Bacteriorodopsinas/genética , Bacteriorodopsinas/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação , Estrutura Secundária de Proteína , Halobacterium salinarum/química , Halobacterium salinarum/genética , Halobacterium salinarum/metabolismo , Modelos Moleculares
19.
Front Cardiovasc Med ; 11: 1374241, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841257

RESUMO

Hereditary transthyretin amyloid (ATTRv) cardiomyopathy (CM) is caused by mutations in the TTR gene. TTR mutations contribute to TTR tetramer destabilization and dissociation, leading to excessive deposition of insoluble amyloid fibrils in the myocardium and finally resulting in cardiac dysfunction. In this article, we report a case of a Chinese patient with transthyretin mutation p.D58Y and provide detailed information on cardiac amyloidosis, including transthoracic echocardiography, cardiac magnetic resonance, and SPECT imaging for the first time. Our report aims to provide a better understanding of ATTR genotypes and phenotypes.

20.
World J Gastrointest Surg ; 16(5): 1363-1370, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38817273

RESUMO

BACKGROUND: A comprehensive understanding of the extrahepatic bile duct anatomy is vital to guide surgical procedures and perform endoscopic retrograde cholangiography. Anatomical irregularities within the extrahepatic bile duct may increase susceptibility to bile duct stones. AIM: To investigate the anatomical risk factors associated with extrahepatic bile ducts in patients diagnosed with choledocholithiasis, with a specific focus on preventing stone recurrence after surgical intervention and endoscopic lithotomy. METHODS: We retrospectively analyzed the medical records of 124 patients without choledocholithiasis and 108 with confirmed choledocholithiasis who underwent magnetic resonance cholangiopancreatography examinations at our center between January 2022 and October 2022. Logistic regression analyses were conducted to identify the anatomical risk factors influencing the incidence of common bile duct stones. RESULTS: Multivariate logistic regression analysis revealed that several factors independently contributed to choledocholithiasis risk. Significant independent risk factors for choledocholithiasis were diameter of the common hepatic [adjusted odds ratio (aOR) = 1.43, 95% confidence interval (CI): 1.07-1.92, adjusted P value = 0.016] and common bile (aOR = 1.68, 95%CI: 1.27-2.23, adjusted P value < 0.001) ducts, length of the common hepatic duct (aOR = 0.92, 95%CI: 0.84-0.99, adjusted P value = 0.034), and angle of the common bile duct (aOR = 0.92, 95%CI: 0.89-0.95, adjusted P value < 0.001). CONCLUSION: The anatomical features of the extrahepatic bile duct were directly associated with choledocholithiasis risk. Key risk factors include an enlarged diameter of the common hepatic and bile ducts, a shorter length of the common hepatic duct, and a reduced angle of the common bile duct.

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