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1.
Cell ; 184(10): 2649-2664.e18, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33848463

RESUMO

Receptor tyrosine kinase (RTK)-mediated activation of downstream effector pathways such as the RAS GTPase/MAP kinase (MAPK) signaling cascade is thought to occur exclusively from lipid membrane compartments in mammalian cells. Here, we uncover a membraneless, protein granule-based subcellular structure that can organize RTK/RAS/MAPK signaling in cancer. Chimeric (fusion) oncoproteins involving certain RTKs including ALK and RET undergo de novo higher-order assembly into membraneless cytoplasmic protein granules that actively signal. These pathogenic biomolecular condensates locally concentrate the RAS activating complex GRB2/SOS1 and activate RAS in a lipid membrane-independent manner. RTK protein granule formation is critical for oncogenic RAS/MAPK signaling output in these cells. We identify a set of protein granule components and establish structural rules that define the formation of membraneless protein granules by RTK oncoproteins. Our findings reveal membraneless, higher-order cytoplasmic protein assembly as a distinct subcellular platform for organizing oncogenic RTK and RAS signaling.


Assuntos
Condensados Biomoleculares/metabolismo , Grânulos Citoplasmáticos/metabolismo , Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Proteínas ras/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Ativação Enzimática , Proteína Adaptadora GRB2/genética , Proteína Adaptadora GRB2/metabolismo , Células HEK293 , Humanos , Proteína SOS1/metabolismo , Transdução de Sinais
2.
Mol Cell ; 83(22): 4123-4140.e12, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37848033

RESUMO

Purinosomes serve as metabolons to enhance de novo purine synthesis (DNPS) efficiency through compartmentalizing DNPS enzymes during stressed conditions. However, the mechanism underpinning purinosome assembly and its pathophysiological functions remains elusive. Here, we show that K6-polyubiquitination of the DNPS enzyme phosphoribosylaminoimidazole carboxylase and phosphoribosylaminoimidazolesuccinocarboxamide synthetase (PAICS) by cullin-5/ankyrin repeat and SOCS box containing 11 (Cul5/ASB11)-based ubiquitin ligase plays a driving role in purinosome assembly. Upon several purinosome-inducing cues, ASB11 is upregulated by relieving the H3K9me3/HP1α-mediated transcriptional silencing, thus stimulating PAICS polyubiquitination. The polyubiquitinated PAICS recruits ubiquitin-associated protein 2 (UBAP2), a ubiquitin-binding protein with multiple stretches of intrinsically disordered regions, thereby inducing phase separation to trigger purinosome assembly for enhancing DNPS pathway flux. In human melanoma, ASB11 is highly expressed to facilitate a constitutive purinosome formation to which melanoma cells are addicted for supporting their proliferation, viability, and tumorigenesis in a xenograft model. Our study identifies a driving mechanism for purinosome assembly in response to cellular stresses and uncovers the impact of purinosome formation on human malignancies.


Assuntos
Ligases , Melanoma , Humanos , Células HeLa , Ubiquitinação , Ubiquitinas
3.
Nature ; 591(7848): 61-65, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658695

RESUMO

Controlling matter-light interactions with cavities is of fundamental importance in modern science and technology1. This is exemplified in the strong-coupling regime, where matter-light hybrid modes form, with properties that are controllable by optical-wavelength photons2,3. By contrast, matter excitations on the nanometre scale are harder to access. In two-dimensional van der Waals heterostructures, a tunable moiré lattice potential for electronic excitations may form4, enabling the generation of correlated electron gases in the lattice potentials5-9. Excitons confined in moiré lattices have also been reported10,11, but no cooperative effects have been observed and interactions with light have remained perturbative12-15. Here, by integrating MoSe2-WS2 heterobilayers in a microcavity, we establish cooperative coupling between moiré-lattice excitons and microcavity photons up to the temperature of liquid nitrogen, thereby integrating versatile control of both matter and light into one platform. The density dependence of the moiré polaritons reveals strong nonlinearity due to exciton blockade, suppressed exciton energy shift and suppressed excitation-induced dephasing, all of which are consistent with the quantum confined nature of the moiré excitons. Such a moiré polariton system combines strong nonlinearity and microscopic-scale tuning of matter excitations using cavity engineering and long-range light coherence, providing a platform with which to study collective phenomena from tunable arrays of quantum emitters.

4.
PLoS Pathog ; 20(6): e1012246, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38857264

RESUMO

Antibody-mediated immunity plays a key role in protection against SARS-CoV-2. We characterized B-cell-derived anti-SARS-CoV-2 RBD antibody repertoires from vaccinated and infected individuals and elucidate the mechanism of action of broadly neutralizing antibodies and dissect antibodies at the epitope level. The breadth and clonality of anti-RBD B cell response varies among individuals. The majority of neutralizing antibody clones lose or exhibit reduced activities against Beta, Delta, and Omicron variants. Nevertheless, a portion of anti-RBD antibody clones that develops after a primary series or booster dose of COVID-19 vaccination exhibit broad neutralization against emerging Omicron BA.2, BA.4, BA.5, BQ.1.1, XBB.1.5 and XBB.1.16 variants. These broadly neutralizing antibodies share genetic features including a conserved usage of the IGHV3-53 and 3-9 genes and recognize three clustered epitopes of the RBD, including epitopes that partially overlap the classically defined set identified early in the pandemic. The Fab-RBD crystal and Fab-Spike complex structures corroborate the epitope grouping of antibodies and reveal the detailed binding mode of broadly neutralizing antibodies. Structure-guided mutagenesis improves binding and neutralization potency of antibody with Omicron variants via a single amino-substitution. Together, these results provide an immunological basis for partial protection against severe COVID-19 by the ancestral strain-based vaccine and indicate guidance for next generation monoclonal antibody development and vaccine design.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , SARS-CoV-2/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Anticorpos Neutralizantes/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Imunização Secundária , Epitopos/imunologia , Linfócitos B/imunologia
5.
Kidney Int ; 106(4): 658-670, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39084257

RESUMO

IgA nephropathy (IgAN) is the most common type of glomerulonephritis that frequently progresses to kidney failure. However, the molecular pathogenesis underlying IgAN remains largely unknown. Here, we investigated the role of galectin-3 (Gal-3), a galactoside-binding protein in IgAN pathogenesis, and showed that Gal-3 expression by the kidney was significantly enhanced in patients with IgAN. In both TEPC-15 hybridoma-derived IgA-induced, passive, and spontaneous "grouped" ddY IgAN models, Gal-3 expression was clearly increased with disease severity in the glomeruli, peri-glomerular regions, and some kidney tubules. Gal-3 knockout (KO) in the passive IgAN model had significantly improved proteinuria, kidney function and reduced severity of kidney pathology, including neutrophil infiltration and decreased differentiation of Th17 cells from kidney-draining lymph nodes, despite increased percentages of regulatory T cells. Gal-3 KO also inhibited the NLRP3 inflammasome, yet it enhanced autophagy and improved kidney inflammation and fibrosis. Moreover, administration of 6-de-O-sulfated, N-acetylated low-molecular-weight heparin, a competitive Gal-3 binding inhibitor, restored kidney function and improved kidney lesions in passive IgAN mice. Thus, our results suggest that Gal-3 is critically involved in IgAN pathogenesis by activating the NLRP3 inflammasome and promoting Th17 cell differentiation. Hence, targeting Gal-3 action may represent a new therapeutic strategy for treatment of this kidney disease.


Assuntos
Modelos Animais de Doenças , Galectina 3 , Glomerulonefrite por IGA , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR , Células Th17 , Glomerulonefrite por IGA/patologia , Glomerulonefrite por IGA/imunologia , Glomerulonefrite por IGA/metabolismo , Glomerulonefrite por IGA/genética , Animais , Galectina 3/metabolismo , Galectina 3/genética , Galectina 3/antagonistas & inibidores , Humanos , Células Th17/imunologia , Células Th17/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Masculino , Feminino , Inflamassomos/metabolismo , Inflamassomos/imunologia , Autofagia/efeitos dos fármacos , Fibrose , Linfócitos T Reguladores/imunologia , Diferenciação Celular , Galectinas/genética , Galectinas/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Camundongos Endogâmicos C57BL , Glomérulos Renais/patologia , Glomérulos Renais/imunologia , Imunoglobulina A/metabolismo , Imunoglobulina A/imunologia
6.
Biochem Biophys Res Commun ; 717: 150045, 2024 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-38718572

RESUMO

The ubiquitin-proteasome system (UPS) plays a key role in maintaining cellular protein homeostasis and participates in modulating various cellular functions. Target of rapamycin (TOR), a highly conserved Ser/Thr kinase found across species from yeasts to humans, forms two multi-protein complexes, TORC1 and TORC2, to orchestrate cellular processes crucial for optimal growth, survival, and stress responses. While UPS-mediated regulation of mammalian TOR complexes has been documented, the ubiquitination of yeast TOR complexes remains largely unexplored. Here we report a functional interplay between the UPS and TORC2 in Saccharomyces cerevisiae. Using avo3-2ts, a temperature-sensitive mutant of the essential TORC2 component Avo3 exhibiting TORC2 defects at restrictive temperatures, we obtained evidence for UPS-dependent protein degradation and downregulation of the TORC2 component Avo2. Our results established the involvement of the E3 ubiquitin ligase Ubr1 and its catalytic activity in mediating Avo2 degradation in cells with defective Avo3. Coimmunoprecipitation revealed the interaction between Avo2 and Ubr1, indicating Avo2 as a potential substrate of Ubr1. Furthermore, depleting Ubr1 rescued the growth of avo3-2ts cells at restrictive temperatures, suggesting an essential role of Avo2 in sustaining cell viability under heat stress and/or TORC2 dysfunction. This study uncovers a role of UPS in yeast TORC2 regulation, highlighting the impact of protein degradation control on cellular signaling.


Assuntos
Regulação para Baixo , Alvo Mecanístico do Complexo 2 de Rapamicina , Complexo de Endopeptidases do Proteassoma , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Ubiquitina-Proteína Ligases , Ubiquitina , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
7.
J Biomed Sci ; 31(1): 44, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685037

RESUMO

BACKGROUND: Helicobacter pylori, the main cause of various gastric diseases, infects approximately half of the human population. This pathogen is auxotrophic for cholesterol which it converts to various cholesteryl α-glucoside derivatives, including cholesteryl 6'-acyl α-glucoside (CAG). Since the related biosynthetic enzymes can be translocated to the host cells, the acyl chain of CAG likely comes from its precursor phosphatidylethanolamine (PE) in the host membranes. This work aims at examining how the acyl chain of CAG and PE inhibits the membrane functions, especially bacterial adhesion. METHODS: Eleven CAGs that differ in acyl chains were used to study the membrane properties of human gastric adenocarcinoma cells (AGS cells), including lipid rafts clustering (monitored by immunofluorescence with confocal microscopy) and lateral membrane fluidity (by the fluorescence recovery after photobleaching). Cell-based and mouse models were employed to study the degree of bacterial adhesion, the analyses of which were conducted by using flow cytometry and immunofluorescence staining, respectively. The lipidomes of H. pylori, AGS cells and H. pylori-AGS co-cultures were analyzed by Ultraperformance Liquid Chromatography-Tandem Mass Spectroscopy (UPLC-MS/MS) to examine the effect of PE(10:0)2, PE(18:0)2, PE(18:3)2, or PE(22:6)2 treatments. RESULTS: CAG10:0, CAG18:3 and CAG22:6 were found to cause the most adverse effect on the bacterial adhesion. Further LC-MS analysis indicated that the treatment of PE(10:0)2 resulted in dual effects to inhibit the bacterial adhesion, including the generation of CAG10:0 and significant changes in the membrane compositions. The initial (1 h) lipidome changes involved in the incorporation of 10:0 acyl chains into dihydro- and phytosphingosine derivatives and ceramides. In contrast, after 16 h, glycerophospholipids displayed obvious increase in their very long chain fatty acids, monounsaturated and polyunsaturated fatty acids that are considered to enhance membrane fluidity. CONCLUSIONS: The PE(10:0)2 treatment significantly reduced bacterial adhesion in both AGS cells and mouse models. Our approach of membrane remodeling has thus shown great promise as a new anti-H. pylori therapy.


Assuntos
Colesterol/análogos & derivados , Helicobacter pylori , Helicobacter pylori/metabolismo , Helicobacter pylori/fisiologia , Camundongos , Animais , Humanos , Lipídeos de Membrana/metabolismo , Linhagem Celular Tumoral , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/metabolismo , Ésteres do Colesterol/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-38772745

RESUMO

BACKGROUND: Albuminuria is common and associated with increased risks of end-stage kidney disease and cardiovascular diseases, yet its underlying mechanism remains obscure. Previous genome-wide association studies (GWAS) for albuminuria did not consider gene pleiotropy and primarily focused on European ancestry populations. This study adopted a multi-trait analysis of GWAS (MTAG) approach to jointly analyze two vital kidney traits, estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR) to identify and prioritize the genes associated with UACR. METHODS: Data from the Taiwan Biobank from 2012 to 2023 were analyzed. GWAS of UACR and eGFR were performed separately and the summary statistics from these GWAS were jointly analyzed using MTAG. The polygenic risk scores (PRS) of UACR were constructed for validation. The UACR-associated loci were further fine-mapped and prioritized based on their deleteriousness, eQTL associations, and relatedness to Mendelian kidney diseases. RESULTS: MTAG analysis of the UACR revealed 15 genetic loci, including 12 novel loci. The PRS for UACR was significantly associated with urinary albumin level (P < 0.001) and microalbuminuria (P = 0.001 ∼ 0.045). A list of priority genes was generated. Twelve genes with high priority included the albumin endocytic receptor gene LRP2 and ciliary genes  IFT172. CONCLUSIONS: The findings of this multi-trait GWAS suggest that primary cilia play a role in sensing mechanical stimuli, leading to albumin endocytosis. The priority list of genes warrants further translational investigation to reduce albuminuria.

9.
Retina ; 44(4): 618-626, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38029422

RESUMO

PURPOSE: To compare the efficiency and safety of internal limiting membrane (ILM) peeling between the Sharkskin forceps and End-grasping forceps in various macular diseases. METHODS: It is a prospective cohort block-randomized study conducted in a tertiary medical center. Seventy subjects with macular hole, epiretinal membrane, vitreomacular traction syndrome, or myopic foveoschisis, receiving pars plana vitrectomy and ILM peeling surgery were equally divided into Sharkskin forceps group and End-grasping forceps group. The duration of ILM peeling, the number of attempts to initiate peeling, and peeling-related retinal damage were evaluated by recorded video and optical coherence tomography. RESULTS: In the Sharkskin group, the authors demonstrated significantly fewer attempts to initiate ILM peeling compared with End-grasping group, with an average of 1.9 and 3.1 attempts ( P = 0.0001) and a lower incidence of retinal microstructural damage (20% vs. 45%, P < 0.0001). Moreover, the mean depth of inner retinal injury at the initiating site exhibited distinct difference postoperatively at 3 months between the Sharkskin group then the End-grasping group (4.3 vs. 30.0 µ m, P = 0.001). CONCLUSION: Sharkskin forceps provide better efficiency and outcome in ILM peeling in patients with various vitreomacular interface diseases, including reduced risk of retinal injury and fewer attempts to initiate ILM flap.


Assuntos
Membrana Epirretiniana , Traumatismos Oculares , Perfurações Retinianas , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Membrana Basal/cirurgia , Retina , Membrana Epirretiniana/cirurgia , Perfurações Retinianas/cirurgia , Traumatismos Oculares/complicações , Vitrectomia/métodos , Tomografia de Coerência Óptica
10.
BMC Geriatr ; 24(1): 370, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664604

RESUMO

BACKGROUND: Intrinsic capacity (IC) is a comprehensive indicator of the overall well-being of older adults, and assessing of IC can help identify early stage of disability and tailor intervention to individual needs. However, there is a lack of effective and simple IC assessment tools. This study aimed to establish predictive scoring algorithms of IC to identify older adults at high risk of impaired functional ability. METHODS: We conducted a cross-sectional study in Southern Taiwan, measuring IC using 7 subitems: cognition, locomotion, vitality, vision, hearing, psychological well-being, and medication usage were measured. Functional ability outcomes included frailty, basic activities of daily living, and instrumental activities of daily living (IADL). The capability of 7 domains of IC in predicting functional ability was assessed by multivariable logistic regression. The prediction of capability of scoring algorithms was indicated by receiver operating characteristic (AUC) curves and measures of sensitivity and specificity. RESULTS: A total of 1,152 older adults were recruited and analyzed. Locomotion emerged as a significant predictor of IADL disability and worsening frailty. The IC-based weighted scoring algorism for predicting IADL demonstrated satisfactory capability (AUC: 0.80), as did the algorithm for predicting worsening frailty (AUC: 0.90). The optimal cutoff points for predicting IADL disability and frailty worse were estimated respectively at 13 and 16, with sensitivity/specificity values of 0.74/0.75 for the IADL prediction algorithm and 0.92/0.77 for the frailty prediction algorithm. CONCLUSION: Our 7-domain IC screening tool proves to be sensitive and practical for early identification of functional disability and frailty among community-dwelling older adults in Taiwan.


Assuntos
Atividades Cotidianas , Algoritmos , Avaliação Geriátrica , Vida Independente , Humanos , Idoso , Masculino , Taiwan/epidemiologia , Feminino , Estudos Transversais , Avaliação Geriátrica/métodos , Idoso de 80 Anos ou mais , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Fragilidade/fisiopatologia , Avaliação da Deficiência
11.
Childs Nerv Syst ; 40(3): 933-937, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37982875

RESUMO

Glioblastoma (GBM) is a rare primary brain tumor in children, and extracranial metastases of pediatric GBM are particularly uncommon. We present the case of a 10-year-old girl with pediatric GBM who developed multiple extracranial metastases, including cervical lymph nodes, spine, and lung. We discuss the rarity of extracranial metastases in GBM and explore possible mechanisms of dissemination. The patient underwent surgical resections, radiotherapy, and chemotherapy, but the metastatic disease progressed despite treatment. We emphasize the need to consider extracranial metastases in pediatric GBM patients and adopt multimodal treatment approaches for managing this rare clinical entity. As the survival rates of pediatric GBM patients are improving, awareness of extracranial metastases is crucial for optimizing treatment outcomes.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Feminino , Criança , Humanos , Glioblastoma/diagnóstico por imagem , Glioblastoma/terapia , Glioblastoma/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Terapia Combinada , Resultado do Tratamento
12.
Ophthalmologica ; : 1-10, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39197428

RESUMO

INTRODUCTION: Anti-vascular endothelial growth factor (VEGF) treatment stands as the primary approach for neovascular age-related macular degeneration (nAMD). Faricimab has recently emerged as a novel anti-VEGF option for nAMD. This study aimed to assess the efficacy of faricimab in patients with refractory nAMD. METHOD: This retrospective study focused on refractory nAMD patients treated with faricimab at Taipei Veterans General Hospital from March 2023 to December 2023. Primary outcomes assessed the change in mean best-corrected visual acuity (BCVA) and central retinal thickness (CRT) over the first 4 months. Secondary outcomes included the presence of subretinal and intraretinal fluid (SRF and IRF) and changes in pigment epithelial detachment (PED). Subgroup analysis for the successful and unsuccessful treatment groups was conducted to identify potential confounding factors influencing treatment response. RESULT: This study included 42 eyes with refractory nAMD treated with faricimab. During a 6-month follow-up, no significant improvement in BCVA was observed, while CRT significantly decreased at all time points, except during the 5-month follow-up. Height PED showed significant reduction up to 5 months. The prevalence of SRF decreased significantly, while IRF remained lower but not significant. According to the treatment criteria, 67.4% successfully met the treatment goals. Subgroup analysis between successful and unsuccessful groups showed no significant differences in baseline characteristics, except a higher predominantly serous PED percentage in the successful group. CONCLUSION: Faricimab showed favorable outcomes in refractory nAMD patients. Further investigations are needed to understand the factors contributing to its efficacy.

13.
Eur Arch Otorhinolaryngol ; 281(6): 3265-3268, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38409582

RESUMO

BACKGROUND: Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a maternally inherited mitochondrial disease that affects various systems in the body, particularly the brain, nervous system, and muscles. Among these systems, sensorineural hearing loss is a common additional symptom. METHODS: A 42-year-old female patient with MELAS who experienced bilateral profound deafness and underwent bilateral sequential cochlear implantation (CIs). Speech recognition and subjective outcomes were evaluated. RESULTS: Following the first CI follow-up, the patient exhibited improved speech recognition ability and decided to undergo the implantation of the second ear just two months after the initial CI surgery. The second CI also demonstrated enhanced speech recognition ability. Subjective outcomes were satisfactory for bilateral CIs. CONCLUSIONS: MELAS patients receiving bilateral CIs can attain satisfactory post-CI speech recognition, spatial hearing, and sound qualities.


Assuntos
Implante Coclear , Implantes Cocleares , Síndrome MELAS , Humanos , Feminino , Adulto , Síndrome MELAS/complicações , Implante Coclear/métodos , Perda Auditiva Neurossensorial/cirurgia , Perda Auditiva Neurossensorial/etiologia , Percepção da Fala
14.
Environ Toxicol ; 39(1): 457-469, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37792803

RESUMO

Irinotecan (IRI), an anticancer drug to treat colon cancer patients, causes cytotoxic effects on normal cells. Phenethyl isothiocyanate (PEITC), rich in common cruciferous plants, has anticancer activities (induction of cell apoptosis) in many human cancer cells, including colon cancer cells. However, the anticancer effects of IRI combined with PEITC on human colon cancer cells in vitro were unavailable. Herein, the aim of this study is to focus on the apoptotic effects of the combination of IRI and PEITC on human colon cancer HCT 116 cells in vitro. Propidium iodide (PI) exclusion and Annexin V/PI staining assays showed that IRI combined with PEITC decreased viable cell number and induced higher cell apoptosis than that of IRI or PEITC only in HCT 116 cells. Moreover, combined treatment induced higher levels of reactive oxygen species (ROS) and Ca2+ than that of IRI or PEITC only. Cells pre-treated with N-acetyl-l-cysteine (scavenger of ROS) and then treated with IRI, PEITC, or IRI combined with PEITC showed increased viable cell numbers than that of IRI or PEITC only. IRI combined with PEITC increased higher caspase-3, -8, and -9 activities than that of IRI or PEITC only by flow cytometer assay. IRI combined with PEITC induced higher levels of ER stress-, mitochondria-, and caspase-associated proteins than that of IRI or PEITC treatment only in HCT 116 cells. Based on these observations, PEITC potentiates IRI anticancer activity by promoting cell apoptosis in the human colon HCT 116 cells. Thus, PEITC may be a potential enhancer for IRI in humans as an anticolon cancer drug in the future.


Assuntos
Apoptose , Neoplasias do Colo , Humanos , Irinotecano/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Células HCT116 , Linhagem Celular Tumoral , Isotiocianatos/farmacologia , Neoplasias do Colo/tratamento farmacológico
15.
J Formos Med Assoc ; 123(3): 307-317, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37586973

RESUMO

Studies have highlighted the significant involvement of kidney pericytes in renal fibrosis. Kidney pericytes, classified as interstitial mesenchymal cells, are extensively branched, collagen-producing cells that closely interact with endothelial cells. This article aims to provide an overview of the recent advancements in understanding the physiological functions of pericytes and their roles in kidney diseases. In a healthy kidney, pericytes have essential physiological function in angiogenesis, erythropoietin (EPO) production, and the regulation of renal blood flow. Nevertheless, pericyte-myofibroblast transition has been identified as the primary cause of disease progression in acute kidney injury (AKI)-to-chronic kidney disease (CKD) continuum. Our recent research has demonstrated that hypoxia-inducible factor-2α (HIF-2α) regulates erythropoietin production in pericytes. However, this production is repressed by EPO gene hypermethylation and HIF-2α downregulation which were induced by transforming growth factor-ß1-activated DNA methyltransferase and activin receptor-like kinase-5 signaling pathway during renal fibrosis, respectively. Additionally, AKI induces epigenetic modifications in pericytes, rendering them more prone to extracellular matrix production, cell migration and proliferation, thereby contributing to subsequent capillary rarefaction and renal fibrosis. Further investigation into the specific functions and roles of different subpopulations of pericytes may contribute for the development of targeted therapies aimed at attenuating kidney disease and mitigating their adverse effects.


Assuntos
Injúria Renal Aguda , Eritropoetina , Nefropatias , Insuficiência Renal Crônica , Humanos , Pericitos/metabolismo , Células Endoteliais/metabolismo , Rim/patologia , Eritropoetina/genética , Injúria Renal Aguda/patologia , Fibrose , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
16.
J Emerg Med ; 66(2): 249-257, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38262784

RESUMO

BACKGROUND: Patients present to emergency departments (EDs) from a variety of backgrounds, which may help inform decision making. OBJECTIVE: This study investigated the clinical characteristics and outcomes of outpatient department (OPD)-referred patients and self-referred patients in the ED. METHODS: We selected nontrauma ED adult patients from a tertiary teaching hospital in Taiwan between August 1, 2020, and October 31, 2020. The acuity levels were determined by dichotomizing the triage classification scores. After propensity score matching, we compared the hospitalization, mortality, and length of ED stay of OPD-referred and self-referred patients. We categorized the patients into "emergency" or "urgent" subgroups according to their triage information and then analyzed the effects of different severity levels. Statistical significance was set at p < 0.05. RESULTS: A total of 564 OPD-referred and 11,959 self-referred patients were included. After propensity score matching, the OPD-referred patients (n = 564), compared with self-referred patients (n = 564), had a higher admission rate (49.8% vs. 28.9%; p < 0.001; odds ratio [OR] 2.44). Among the emergency subgroup patients, there was no significant difference between OPD-referred patients (n = 131) and self-referred patients (n = 138) regarding the admission rate (p = 0.257) or the mortality rate (p = 0.253). Among the urgent subgroup patients, OPD-referred patients (n = 433), compared with self-referred patients (n = 426), had a significantly higher admission rate (46.0% vs. 20.2%; p < 0.001; OR 3.36), but not mortality rate (2.1% vs. 0.5%; p = 0.064). Regarding the length of ED stay, OPD-referred and self-referred patients had a significant difference only in the "urgent and discharged" subgroup (5.8 vs. 2.3 h; p < 0.001). CONCLUSIONS: OPD-referred ED patients might have more severe and complex conditions and need comprehensive care management.


Assuntos
Hospitalização , Pacientes Ambulatoriais , Adulto , Humanos , Serviço Hospitalar de Emergência , Alta do Paciente , Hospitais de Ensino , Estudos Retrospectivos
17.
J Formos Med Assoc ; 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39389802

RESUMO

BACKGROUND: The effect of exact classes of lipid-lowering drugs (LLDs) on preventing major adverse cardiovascular events (MACEs) and poor renal outcomes is not well characterized in the chronic kidney disease (CKD) population. METHODS: We performed a frequentist random-effects network meta-analysis of randomized controlled trials (RCTs) to evaluate the protective effect of the LLDs in non-dialysis CKD patients. The PubMed, Embase, Web of Science, and Cochrane Library databases were systematically searched for relevant trials published before March 31, 2024. The primary outcome was the incidence of MACEs. The secondary outcomes comprised all-cause mortality, end-stage kidney disease, changes in estimated glomerular filtration rate (eGFR) and proteinuria, and safety. RESULTS: Forty-nine eligible RCTs with 77,826 participants with non-dialysis CKD were included. With moderate confidence in the evidence, rosuvastatin and atorvastatin showed statistically significantly more efficacy in reducing the risk of MACE, with a pooled risk ratio of 0.55 (95% CI 0.33-0.91) for rosuvastatin and 0.67 (0.49-0.90) for atorvastatin, respectively, compared with the control group. For the change in the eGFR, atorvastatin (mean difference [MD], 1.40; 95% CI, 0.61 to 2.18), rosuvastatin (MD, 1.73; 95% CI, 0.63 to 2.83), and statin plus ezetimibe (MD, 2.35; 95% CI, 0.44 to 4.26) showed statistically significant increases in the mean eGFR. CONCLUSION: In patients with non-dialysis CKD, there is sufficient evidence to show that rosuvastatin and atorvastatin were statistically significantly more effective and preferable in reducing the risk of MACE and increasing the mean eGFR compared with the control group.

18.
Microsurgery ; 44(4): e31186, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38716649

RESUMO

INTRODUCTION: Free flap transfer for head and neck defects has gained worldwide acceptance. Because flap failure is a devastating outcome, studies have attempted to identify risk factors-including renal failure. We sought to determine whether end-stage renal disease (ESRD) patients undergoing dialysis are at increased risk of flap failure following microsurgical head and neck reconstruction. PATIENTS AND METHODS: The study's participants were patients who underwent free flap reconstruction in the head and neck region at Hualien Tzu Chi Hospital between January 2010 and December 2019. We used the National Health Insurance "Specific Diagnosis and Treatment Code" to identify patients undergoing dialysis; these patients comprised the dialysis group, whose members were matched to a non-dialysis group for age and gender. The dependent variables were flap survival rate, take-back rate, and flap failure risk between the dialysis and non-dialysis groups. RESULTS: We included 154 patients in the dialysis (n = 14) and non-dialysis (n = 140) groups. The groups were similar in terms of age and most comorbidities, except diabetes mellitus, hypertension, and coronary artery disease, which were more prevalent in the dialysis group. The dialysis and non-dialysis groups had similar flap survival rates (100% vs. 92.9%; p = .600). Twenty-three patients underwent take-back surgery, most in the non-dialysis group (14.3% vs. 15.0%; p = 1.000). Patients in the dialysis group were more likely to have prolonged intensive care unit stays; however, dialysis alone did not predict flap failure (OR: 0.83; p = .864). CONCLUSION: This study found no significant differences in free flap survival and take-back rates between patients with and without dialysis. Dialysis did not increase the risk of flap failure following microsurgical head and neck reconstruction in this study; however, prospective, randomized controlled trials are needed.


Assuntos
Retalhos de Tecido Biológico , Neoplasias de Cabeça e Pescoço , Falência Renal Crônica , Microcirurgia , Procedimentos de Cirurgia Plástica , Diálise Renal , Humanos , Masculino , Feminino , Falência Renal Crônica/terapia , Falência Renal Crônica/complicações , Pessoa de Meia-Idade , Retalhos de Tecido Biológico/transplante , Procedimentos de Cirurgia Plástica/métodos , Microcirurgia/métodos , Neoplasias de Cabeça e Pescoço/cirurgia , Neoplasias de Cabeça e Pescoço/complicações , Idoso , Estudos Retrospectivos , Sobrevivência de Enxerto , Fatores de Risco , Adulto
19.
Int J Mol Sci ; 25(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38791301

RESUMO

Psychological stress increases risk of gastrointestinal tract diseases. However, the mechanism behind stress-induced gastrointestinal injury is not well understood. The objective of our study is to elucidate the putative mechanism of stress-induced gastrointestinal injury and develop an intervention strategy. To achieve this, we employed the restraint stress mouse model, a well-established method to study the pathophysiological changes associated with psychological stress in mice. By orally administering gut-nonabsorbable Evans blue dye and monitoring its plasma levels, we were able to track the progression of gastrointestinal injury in live mice. Additionally, flow cytometry was utilized to assess the viability, death, and inflammatory status of splenic leukocytes, providing insights into the stress-induced impact on the innate immune system associated with stress-induced gastrointestinal injury. Our findings reveal that neutrophils represent the primary innate immune leukocyte lineage responsible for stress-induced inflammation. Splenic neutrophils exhibited elevated expression levels of the pro-inflammatory cytokine IL-1, cellular reactive oxygen species, mitochondrial burden, and cell death following stress challenge compared to other innate immune cells such as macrophages, monocytes, and dendritic cells. Regulated cell death analysis indicated that NETosis is the predominant stress-induced cell death response among other analyzed regulated cell death pathways. NETosis culminates in the formation and release of neutrophil extracellular traps, which play a crucial role in modulating inflammation by binding to pathogens. Treatment with the NETosis inhibitor GSK484 rescued stress-induced neutrophil extracellular trap release and gastrointestinal injury, highlighting the involvement of neutrophil extracellular traps in stress-induced gastrointestinal inflammation. Our results suggest that neutrophil NETosis could serve as a promising drug target for managing psychological stress-induced gastrointestinal injuries.


Assuntos
Inflamação , Neutrófilos , Restrição Física , Estresse Psicológico , Animais , Camundongos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Estresse Psicológico/complicações , Estresse Psicológico/imunologia , Inflamação/patologia , Masculino , Camundongos Endogâmicos C57BL , Armadilhas Extracelulares/metabolismo , Gastroenteropatias/etiologia , Modelos Animais de Doenças , Espécies Reativas de Oxigênio/metabolismo
20.
Molecules ; 29(15)2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39124977

RESUMO

The steady low-Reynolds-number rotation of a chain of coaxial soft spheres (each with an impermeable hard core covered by a permeable porous layer) about the axis in a viscous fluid is analyzed. The particles may be unequally spaced, and may differ in the permeability and inner and outer radii of the porous surface layer as well as angular velocity. By using a method of boundary collocation, the Stokes and Brinkman equations for the external fluid flow and flow within the surface layers, respectively, are solved semi-analytically. The particle interaction effect increases as the relative gap thickness between adjacent particles or their permeability decreases, which can be significant as the gap thickness approaches zero. A particle's hydrodynamic torque is reduced (its rotation is enhanced) when other particles rotate in the same direction at equivalent or greater angular velocities, but increases (its rotation is hindered) when other particles rotate in the opposite direction at arbitrary angular velocities. For particles with different radii or permeabilities, the particle interaction has a greater effect on smaller or more permeable particles than on larger or less permeable particles. For the rotation of three particles, the presence of the third particle can significantly affect the hydrodynamic torques acting on the other two particles. For the rotation of numerous particles, shielding effects between particles can be substantial. When the permeability of porous layers is low, relative fluid motion is barely felt by the hard cores of the soft particles. The insights gained from this analysis on the effects of interactions among rotating soft particles may be of great importance in many physicochemical applications of colloidal suspensions.

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