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1.
Artículo en Inglés | MEDLINE | ID: mdl-38683872

RESUMEN

Although ventricular capture during the atrial threshold test is possible, there are rare reports on the insulation defect and inactive leads thereof. In this case, we present a pacemaker-dependent patient with a history of pacemaker generator replacements. The patient experienced ventricular capture induced by atrial pacing due to adhesion of the atrial and ventricular leads with an insulation defect. The atrial lead was abandoned and a new lead was implanted. However, there was a significant decrease in ventricular impedance detected shortly after the new lead was implanted. When observing the phenomenon of atrial pacing-induced ventricular depolarization, one uncommon reason to consider is lead adhesive wear. It is important to pay attention to the contact and bending sites of the leads.

3.
Front Pharmacol ; 14: 1243505, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38089059

RESUMEN

Background: We hypothesize that the poor survival outcomes of end-stage kidney disease (ESKD) patients undergoing hemodialysis are associated with a low filtering efficiency and selectivity. The current gold standard criteria using single or several markers show an inability to predict or disclose the treatment effect and disease progression accurately. Methods: We performed an integrated mass spectrometry-based metabolomic and proteomic workflow capable of detecting and quantifying circulating small molecules and proteins in the serum of ESKD patients. Markers linked to cardiovascular disease (CVD) were validated on human induced pluripotent stem cell (iPSC)-derived cardiomyocytes. Results: We identified dozens of elevated molecules in the serum of patients compared with healthy controls. Surprisingly, many metabolites, including lipids, remained at an elevated blood concentration despite dialysis. These molecules and their associated physical interaction networks are correlated with clinical complications in chronic kidney disease. This study confirmed two uremic toxins associated with CVD, a major risk for patients with ESKD. Conclusion: The retained molecules and metabolite-protein interaction network address a knowledge gap of candidate uremic toxins associated with clinical complications in patients undergoing dialysis, providing mechanistic insights and potential drug discovery strategies for ESKD.

4.
Am J Pathol ; 193(10): 1501-1516, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37676196

RESUMEN

Chronic kidney disease (CKD) is characterized by the accumulation of uremic toxins and renal tubular damage. Tryptophan-derived uremic toxins [indoxyl sulfate (IS) and kynurenine (Kyn)] are well-characterized tubulotoxins. Emerging evidence suggests that transmembrane and immunoglobulin domain-containing 1 (TMIGD1) protects tubular cells and promotes survival. However, the direct molecular mechanism(s) underlying how these two opposing pathways crosstalk remains unknown. We posited that IS and Kyn mediate tubular toxicity through TMIGD1 and the loss of TMIGD1 augments tubular injury. Results from the current study showed that IS and Kyn suppressed TMIGD1 transcription in tubular cells in a dose-dependent manner. The wild-type CCAAT enhancer-binding protein ß (C/EBPß) enhanced, whereas a dominant-negative C/EBPß suppressed, TMIGD1 promoter activity. IS down-regulated C/EBPß in primary human renal tubular cells. The adenine-induced CKD, unilateral ureteric obstruction, and deoxycorticosterone acetate salt unilateral nephrectomy models showed reduced TMIGD1 expression in the renal tubules, which correlated with C/EBPß expression. C/EBPß levels negatively correlated with the IS and Kyn levels. Inactivation of TMIGD1 in mice significantly lowered acetylated tubulin, decreased tubular cell proliferation, caused severe tubular damage, and worsened renal function. Thus, the current results demonstrate that TMIGD1 protects renal tubular cells from renal injury in different models of CKD and uncovers a novel mechanism of tubulotoxicity of tryptophan-based uremic toxins.


Asunto(s)
Insuficiencia Renal Crónica , Triptófano , Humanos , Animales , Ratones , Tóxinas Urémicas , Riñón/fisiología , Dominios de Inmunoglobulinas , Glicoproteínas de Membrana
5.
J Vis Exp ; (185)2022 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-35938794

RESUMEN

Murine models are employed to probe various aspects of peritoneal dialysis (PD), such as peritoneal inflammation and fibrosis. These events drive peritoneal membrane failure in humans, which remains an area of intense investigation due to its profound clinical implications in managing patients with end-stage kidney disease (ESKD). Despite the clinical importance of PD and its related complications, current experimental murine models suffer from key technical challenges that compromise the models' performance. These include PD catheter migration and kinking and usually warrant earlier catheter removal. These limitations also drive the need for a greater number of animals to complete a study. Addressing these drawbacks, this study introduces technical improvements and surgical nuances to prevent commonly observed PD catheter complications in a murine model. Moreover, this modified model is validated by inducing peritoneal inflammation and fibrosis using lipopolysaccharide injections. In essence, this paper describes an improved method to create an experimental model of PD.


Asunto(s)
Fallo Renal Crónico , Diálisis Peritoneal , Animales , Cateterismo/métodos , Catéteres de Permanencia , Fibrosis , Humanos , Inflamación , Ratones , Diálisis Peritoneal/efectos adversos , Diálisis Peritoneal/métodos
6.
Am J Pathol ; 192(8): 1167-1185, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35710032

RESUMEN

Aberrant hyperactivation of Wnt signaling, driven by nuclear ß-catenin in the colonic epithelium, represents the seminal event in the initiation and progression of colorectal cancer (CRC). Despite its established role in CRC tumorigenesis, clinical translation of Wnt inhibitors remains unsuccessful. Late SV40 factor (LSF; encoded by TFCP2) is a transcription factor and a potent oncogene. The current study identified a chemotype, named factor quinolinone inhibitors (FQIs), that specifically inhibits LSF DNA-binding, partner protein-binding, and transactivation activities. The role of LSF and FQIs in CRC tumor growth was examined. Herein, the study showed that LSF and ß-catenin interacted in several CRC cell lines irrespective of their mutational profile, which was disrupted by FQI2-34. FQI2-34 suppressed Wnt activity in CRC cells in a dose-dependent manner. Leveraging both allogeneic and syngeneic xenograft models showed that FQI2-34 suppressed CRC tumor growth, significantly reduced nuclear ß-catenin, and down-regulated Wnt targets such as axis inhibition protein 2 (AXIN-2) and SRY-box transcription factor 9, in the xenograft cells. FQI2-34 suppressed the proliferation of xenograft cells. Adenocarcinomas from a series of stage IV CRC patients revealed a positive correlation between LSF expression and Wnt targets (AXIN-2 and SRY-box transcription factor 9) within the CRC cells. Collectively, this study uncovers the Wnt inhibitory and CRC growth-suppressive effects of these LSF inhibitors in CRC cells, revealing a novel target in CRC therapeutics.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Trasplante de Células Madre Hematopoyéticas , Proteína Axina/metabolismo , Línea Celular Tumoral , Proliferación Celular , Neoplasias del Colon/tratamiento farmacológico , Neoplasias Colorrectales/patología , Proteínas de Unión al ADN/metabolismo , Regulación Neoplásica de la Expresión Génica , Xenoinjertos , Humanos , Factores de Transcripción/metabolismo , Vía de Señalización Wnt , beta Catenina/metabolismo
7.
J Am Soc Nephrol ; 33(3): 565-582, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35091451

RESUMEN

BACKGROUND: Endothelial cell injury is a common nidus of renal injury in patients and consistent with the high prevalence of AKI reported during the coronavirus disease 2019 pandemic. This cell type expresses integrin α5 (ITGA5), which is essential to the Tie2 signaling pathway. The microRNA miR-218-5p is upregulated in endothelial progenitor cells (EPCs) after hypoxia, but microRNA regulation of Tie2 in the EPC lineage is unclear. METHODS: We isolated human kidney-derived EPCs (hkEPCs) and surveyed microRNA target transcripts. A preclinical model of ischemic kidney injury was used to evaluate the effect of hkEPCs on capillary repair. We used a genetic knockout model to evaluate the effect of deleting endogenous expression of miR-218 specifically in angioblasts. RESULTS: After ischemic in vitro preconditioning, miR-218-5p was elevated in hkEPCs. We found miR-218-5p bound to ITGA5 mRNA transcript and decreased ITGA5 protein expression. Phosphorylation of 42/44 MAPK decreased by 73.6% in hkEPCs treated with miR-218-5p. Cells supplemented with miR-218-5p downregulated ITGA5 synthesis and decreased 42/44 MAPK phosphorylation. In a CD309-Cre/miR-218-2-LoxP mammalian model (a conditional knockout mouse model designed to delete pre-miR-218-2 exclusively in CD309+ cells), homozygotes at e18.5 contained avascular glomeruli, whereas heterozygote adults showed susceptibility to kidney injury. Isolated EPCs from the mouse kidney contained high amounts of ITGA5 and showed decreased migratory capacity in three-dimensional cell culture. CONCLUSIONS: These results demonstrate the critical regulatory role of miR-218-5p in kidney EPC migration, a finding that may inform efforts to treat microvascular kidney injury via therapeutic cell delivery.


Asunto(s)
Lesión Renal Aguda/etiología , Lesión Renal Aguda/metabolismo , Células Progenitoras Endoteliales/metabolismo , Células Progenitoras Endoteliales/patología , Integrina alfa5/metabolismo , MicroARNs/fisiología , Lesión Renal Aguda/patología , Animales , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor TIE-2/fisiología , Transducción de Señal/fisiología
8.
J Clin Invest ; 132(1)2022 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-34752422

RESUMEN

Chronic kidney disease (CKD) imposes a strong and independent risk for peripheral artery disease (PAD). While solutes retained in CKD patients (uremic solutes) inflict vascular damage, their role in PAD remains elusive. Here, we show that the dietary tryptophan-derived uremic solutes including indoxyl sulfate (IS) and kynurenine (Kyn) at concentrations corresponding to those in CKD patients suppress ß-catenin in several cell types, including microvascular endothelial cells (ECs), inhibiting Wnt activity and proangiogenic Wnt targets in ECs. Mechanistic probing revealed that these uremic solutes downregulated ß-catenin in a manner dependent on serine 33 in its degron motif and through the aryl hydrocarbon receptor (AHR). Hindlimb ischemia in adenine-induced CKD and IS solute-specific mouse models showed diminished ß-catenin and VEGF-A in the capillaries and reduced capillary density, which correlated inversely with blood levels of IS and Kyn and AHR activity in ECs. An AHR inhibitor treatment normalized postischemic angiogenic response in CKD mice to a non-CKD level. In a prospective cohort of PAD patients, plasma levels of tryptophan metabolites and plasma's AHR-inducing activity in ECs significantly increased the risk of future adverse limb events. This work uncovers the tryptophan metabolite/AHR/ß-catenin axis as a mediator of microvascular rarefaction in CKD patients and demonstrates its targetability for PAD in CKD models.


Asunto(s)
Miembro Posterior/irrigación sanguínea , Indicán/metabolismo , Isquemia/metabolismo , Quinurenina/metabolismo , Insuficiencia Renal Crónica/metabolismo , Triptófano/metabolismo , Vía de Señalización Wnt , Anciano , Anciano de 80 o más Años , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Humanos , Isquemia/etiología , Isquemia/patología , Ratones , Persona de Mediana Edad , Receptores de Hidrocarburo de Aril/metabolismo , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/patología
9.
ACS Cent Sci ; 7(7): 1156-1165, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34341769

RESUMEN

As the COVID-19 pandemic continues to spread, investigating the processes underlying the interactions between SARS-CoV-2 and its hosts is of high importance. Here, we report the identification of CD209L/L-SIGN and the related protein CD209/DC-SIGN as receptors capable of mediating SARS-CoV-2 entry into human cells. Immunofluorescence staining of human tissues revealed prominent expression of CD209L in the lung and kidney epithelia and endothelia. Multiple biochemical assays using a purified recombinant SARS-CoV-2 spike receptor-binding domain (S-RBD) or S1 encompassing both N termal domain and RBD and ectopically expressed CD209L and CD209 revealed that CD209L and CD209 interact with S-RBD. CD209L contains two N-glycosylation sequons, at sites N92 and N361, but we determined that only site N92 is occupied. Removal of the N-glycosylation at this site enhances the binding of S-RBD with CD209L. CD209L also interacts with ACE2, suggesting a role for heterodimerization of CD209L and ACE2 in SARS-CoV-2 entry and infection in cell types where both are present. Furthermore, we demonstrate that human endothelial cells are permissive to SARS-CoV-2 infection, and interference with CD209L activity by a knockdown strategy or with soluble CD209L inhibits virus entry. Our observations demonstrate that CD209L and CD209 serve as alternative receptors for SARS-CoV-2 in disease-relevant cell types, including the vascular system. This property is particularly important in tissues where ACE2 has low expression or is absent and may have implications for antiviral drug development.

10.
Quant Imaging Med Surg ; 11(3): 983-997, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33654671

RESUMEN

BACKGROUND: Conventional light sheet fluorescence microscopy (LSFM), or selective plane illumination microscopy (SPIM), enables high-resolution 3D imaging over a large volume by using two orthogonally aligned objective lenses to decouple excitation and emission. The recent development of oblique plane microscopy (OPM) simplifies LSFM design with only one single objective lens, by using off-axis excitation and remote focusing. However, most reports on OPM have a limited microscopic field of view (FOV), typically within 1×1 mm2. Our goal is to overcome the limitation with a new variant of OPM to achieve a mesoscopic FOV. METHODS: We implemented an optical design of mesoscopic scanning OPM to allow the use of low numerical aperture (NA) objective lenses. The angle of the intermediate image before the remote focusing system was increased by a demagnification under Scheimpflug condition such that the light collecting efficiency in the remote focusing system was significantly improved. A telescope composed of cylindrical lenses was used to correct the distorted image caused by the demagnification design. We characterized the 3D resolutions and imaging volume by imaging fluorescent microspheres, and demonstrated the volumetric imaging on intact whole zebrafish larvae, mouse cortex, and multiple Caenorhabditis elegans (C. elegans). RESULTS: We demonstrate a mesoscopic FOV up to ~6×5×0.6 mm3 volumetric imaging, the largest reported FOV by OPM so far. The angle of the intermediate image plane is independent of the magnification as long as the size of the pupil aperture of the objectives is the same. As a result, the system is highly versatile, allowing simple switching between different objective lenses with low (10×, NA 0.3) and median NA (20×, NA 0.5). Detailed microvasculature in zebrafish larvae, mouse cortex, and neurons in C. elegans are clearly visualized in 3D. CONCLUSIONS: The proposed mesoscopic scanning OPM allows using low NA objectives such that centimeter-level FOV volumetric imaging can be achieved. With the extended FOV, simple sample mounting protocol, and the versatility of changeable FOVs/resolutions, our system will be ready for the varieties of applications requiring in vivo volumetric imaging over large length scales.

11.
bioRxiv ; 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-32607506

RESUMEN

As the COVID-19 pandemic continues to spread, investigating the processes underlying the interactions between SARS-CoV-2 and its hosts is of high importance. Here, we report the identification of CD209L/L-SIGN and the related protein CD209/DC-SIGN as receptors capable of mediating SARS-CoV-2 entry into human cells. Immunofluorescence staining of human tissues revealed prominent expression of CD209L in the lung and kidney epithelium and endothelium. Multiple biochemical assays using a purified recombinant SARS-CoV-2 spike receptor binding domain (S-RBD) or S1 encompassing both NTB and RBD and ectopically expressed CD209L and CD209 revealed that CD209L and CD209 interact with S-RBD. CD209L contains two N-glycosylation sequons, at sites N92 and N361, but we determined that only site N92 is occupied. Removal of the N-glycosylation at this site enhances the binding of S-RBD with CD209L. CD209L also interacts with ACE2, suggesting a role for heterodimerization of CD209L and ACE2 in SARS-CoV-2 entry and infection in cell types where both are present. Furthermore, we demonstrate that human endothelial cells are permissive to SARS-CoV-2 infection and interference with CD209L activity by knockdown strategy or with soluble CD209L inhibits virus entry. Our observations demonstrate that CD209L and CD209 serve as alternative receptors for SARS-CoV-2 in disease-relevant cell types, including the vascular system. This property is particularly important in tissues where ACE2 has low expression or is absent, and may have implications for antiviral drug development.

12.
Cells ; 9(11)2020 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-33142844

RESUMEN

COVID-19 infection has protean systemic manifestations. Experience from previous coronavirus outbreaks, including the current SARS-CoV-2, has shown an augmented risk of thrombosis of both macrovasculature and microvasculature. The former involves both arterial and venous beds manifesting as stroke, acute coronary syndrome and venous thromboembolic events. The microvascular thrombosis is an underappreciated complication of SARS-CoV-2 infection with profound implications on the development of multisystem organ failure. The telltale signs of perpetual on-going coagulation and fibrinolytic cascades underscore the presence of diffuse endothelial damage in the patients with COVID-19. These parameters serve as strong predictors of mortality. While summarizing the alterations of various components of thrombosis in patients with COVID-19, this review points to the emerging evidence that implicates the prominent role of the extrinsic coagulation cascade in COVID-19-related coagulopathy. These mechanisms are triggered by widespread endothelial cell damage (endotheliopathy), the dominant driver of macro- and micro-vascular thrombosis in these patients. We also summarize other mediators of thrombosis, clinically relevant nuances such as the occurrence of thromboembolic events despite thromboprophylaxis (breakthrough thrombosis), current understanding of systemic anticoagulation therapy and its risk-benefit ratio. We conclude by emphasizing a need to probe COVID-19-specific mechanisms of thrombosis to develop better risk markers and safer therapeutic targets.


Asunto(s)
COVID-19/sangre , COVID-19/patología , SARS-CoV-2/patogenicidad , Tromboembolia Venosa/virología , Anticoagulantes/farmacología , Coagulación Sanguínea/efectos de los fármacos , COVID-19/metabolismo , Humanos , Trombosis/metabolismo , Trombosis/fisiopatología , Tromboembolia Venosa/sangre , Tromboembolia Venosa/tratamiento farmacológico , Tromboembolia Venosa/patología
13.
Am J Pathol ; 190(3): 642-659, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31972158

RESUMEN

Ischemia due to hypoperfusion is one of the most common forms of acute kidney injury. We hypothesized that kidney hypoxia initiates the up-regulation of miR-218 expression in endothelial progenitor cells (EPCs) to guide endocapillary repair. Murine renal artery-derived EPCs (CD34+/CD105-) showed down-regulation of mmu-Mir218-5p/U6 RNA ratio after ischemic injury, while in human renal arteries, MIR218-5p expression was up-regulated after ischemic injury. MIR218 expression was clarified in cell culture experiments in which increases in both SLIT3 and MIR218-2-5p expressions were observed after 5 minutes of hypoxia. ROBO1 transcript, a downstream target of MIR218-2-5p, showed inverse expression to MIR218-2-5p. EPCs transfected with a MIR218-5p inhibitor in three-dimensional normoxic culture showed premature capillary formation. Organized progenitor cell movement was reconstituted when cells were co-transfected with Dicer siRNA and low-dose Mir218-5p mimic. A Mir218-2 knockout was generated to assess the significance of miR-218-2 in a mammalian model. Mir218-2-5p expression was decreased in Mir218-2-/- embryos at E16.5. Mir218-2-/- decreased CD34+ angioblasts in the ureteric bud at E16.5 and were nonviable. Mir218-2+/- decreased peritubular capillary density at postnatal day 14 and increased serum creatinine after ischemia in adult mice. Systemic injection of miR-218-5p decreased serum creatinine after injury. These experiments demonstrate that miR-218 expression can be triggered by hypoxia and modulates EPC migration in the kidney.


Asunto(s)
Lesión Renal Aguda/patología , Isquemia/patología , MicroARNs/genética , Proteínas del Tejido Nervioso/metabolismo , Receptores Inmunológicos/metabolismo , Adulto , Anciano , Animales , ARN Helicasas DEAD-box , Modelos Animales de Enfermedad , Células Progenitoras Endoteliales/patología , Femenino , Humanos , Riñón/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microvasos/patología , Persona de Mediana Edad , Proteínas del Tejido Nervioso/genética , Receptores Inmunológicos/genética , Ribonucleasa III , Proteínas Roundabout
14.
Blood Purif ; 49(5): 586-596, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31935721

RESUMEN

INTRODUCTION: Catheter-related blood stream infection (CRBSI), the most common complication of central vein catheter (CVC), was closely associated with high morbidity and mortality in hemodialysis (HD) patients. Conjunction with systemic antibiotic, antibiotic lock (ABL) is an important therapeutic option to salvage the catheter. With extra antimicrobial and biofilm removing properties, urokinase plasminogen activator (uPA)-based ABL could have a potential role in the treatment of CRBSI. OBJECTIVE: In this study, we aimed to explore effectiveness of uPA-based (ABL) on microorganisms embedded in biofilms in vitro and CVC salvage rate in HD patients with CRBSI. METHODS: In vitro, we induced biofilms formation on the surface of HD catheter by mimicking the development of CRBSI. Applying uPA with or without antibiotics on the kinds of microorganism biofilms to explore its antimicrobial and biofilm removing properties. In vivo, 86 HD patients diagnosed as CRBSI were retrospectively enrolled to see effectiveness of uPA-based ABL on catheter salvage rate as compare to heparin-based ABL. RESULTS: uPA was effect to Staphylococcus epidermidis biofilms compared to Staphylococcus aureus, Escherichia coli, and Candida albicans. Less biofilm residues made the regrowth of S. epidermidis also limited. The combination of uPA with antibiotic showed better antimicrobial and antibiofilm activity than uPA alone or heparin-based ABL in vitro and in vivo. Among HD patients, uPA-based ABL did not cause any obvious adverse affects, and it was more effective in treating coagulase-negative Staphylococci related CRBSI than other microorganisms. CONCLUSIONS: The combination of uPA and a therapeutic plasma concentration of sensitive antibiotic can work together to effectively remove coagulase-negative S. epidermidis embedded in biofilms in vitro. uPA-based ABL is safe and effective therapeutic intervention for HD patients with CRBSI, especially compared to heparin-based ABL.


Asunto(s)
Bacterias/crecimiento & desarrollo , Fenómenos Fisiológicos Bacterianos , Biopelículas/crecimiento & desarrollo , Infecciones Relacionadas con Catéteres , Catéteres Venosos Centrales/microbiología , Desinfección , Diálisis Renal , Activador de Plasminógeno de Tipo Uroquinasa/administración & dosificación , Bacterias/clasificación , Infecciones Relacionadas con Catéteres/microbiología , Infecciones Relacionadas con Catéteres/prevención & control , Femenino , Humanos , Masculino , Persona de Mediana Edad
15.
ACS Appl Bio Mater ; 3(1): 59-67, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35019427

RESUMEN

Iron can enter the electron-rich cavities of graphitic carbon nitride (g-C3N4). On account of this phenomenon, Fe-doped g-C3N4 (Fe-g-C3N4) was prepared as a peroxidase mimetic by using one-step pyrolysis of urea and FeCl3·6H2O. Compared to g-C3N4, Fe-g-C3N4 has a large specific surface area due to the presence of mesopores and cracks, a smaller band gap, and a high loading of Fe in its structure. Thus, Fe-g-C3N4 exhibits greater peroxidase activity with a more obvious color change when using 3,3',5,5'-tetramethylbenzidine (TMB) as a substrate in the presence of hydrogen peroxide (H2O2). The color of a mixture of TMB and Fe-g-C3N4 gradually deepens with increasing concentrations of H2O2. Accordingly, a rapid, sensitive, and low-cost colorimetric assay for the detection of H2O2 was developed. After optimization, this method boasts a wide linear dynamic range for H2O2 detection from 0.005 to 400 µM (r2 = 0.9971) with a detection limit of 0.005 µM. Because H2O2 is a main product of glucose oxidation by glucose oxidase (GOx), a colorimetric assay for glucose detection was also realized, with a linear dynamic range of 1-1000 µM (r2 = 0.9996) and a detection limit of 0.5 µM. These assays were applied to the quantitative detection of H2O2 in milk and glucose in human serum, respectively.

16.
Nat Prod Res ; 34(12): 1687-1693, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30449168

RESUMEN

A new naturally occurring trinoreudesmane sesquiterpene, artahongkongol A (1), together with seven known eudesmane sesquiterpenes (2-8), was isolated from the stems and leaves of Artabotrys hongkongensis Hance. Among them, 1 is a rare trinoreudesmane sesquiterpene containing 12 carbon atoms on the carbon skeleton. All known compounds (2-8) were isolated from the genus Artabotrys for the first time. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1-8 showed significant inhibitory effects against various human cancer cell lines with IC50 values ranging from 0.57 to 15.68 µM.


Asunto(s)
Annonaceae/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Sesquiterpenos de Eudesmano/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Concentración 50 Inhibidora , Estructura Molecular , Hojas de la Planta/química , Tallos de la Planta/química , Sesquiterpenos de Eudesmano/química , Sesquiterpenos de Eudesmano/farmacología
17.
Blood ; 134(26): 2399-2413, 2019 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-31877217

RESUMEN

Patients with malignancy are at 4- to 7-fold higher risk of venous thromboembolism (VTE), a potentially fatal, yet preventable complication. Although general mechanisms of thrombosis are enhanced in these patients, malignancy-specific triggers and their therapeutic implication remain poorly understood. Here we examined a colon cancer-specific VTE model and probed a set of metabolites with prothrombotic propensity in the inferior vena cava (IVC) ligation model. Athymic mice injected with human colon adenocarcinoma cells exhibited significantly higher IVC clot weights, a biological readout of venous thrombogenicity, compared with the control mice. Targeted metabolomics analysis of plasma of mice revealed an increase in the blood levels of kynurenine and indoxyl sulfate (tryptophan metabolites) in xenograft-bearing mice, which correlated positively with the increase in the IVC clot size. These metabolites are ligands of aryl hydrocarbon receptor (AHR) signaling. Accordingly, plasma from the xenograft-bearing mice activated the AHR pathway and augmented tissue factor (TF) and plasminogen activator inhibitor 1 (PAI-1) levels in venous endothelial cells in an AHR-dependent manner. Consistent with these findings, the endothelium from the IVC of xenograft-bearing animals revealed nuclear AHR and upregulated TF and PAI-1 expression, telltale signs of an activated AHR-TF/PAI-1 axis. Importantly, pharmacological inhibition of AHR activity suppressed TF and PAI-1 expression in endothelial cells of the IVC and reduced clot weights in both kynurenine-injected and xenograft-bearing mice. Together, these data show dysregulated tryptophan metabolites in a mouse cancer model, and they reveal a novel link between these metabolites and the control of the AHR-TF/PAI-1 axis and VTE in cancer.


Asunto(s)
Neoplasias del Colon/complicaciones , Modelos Animales de Enfermedad , Metaboloma , Inhibidor 1 de Activador Plasminogénico/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Tromboplastina/metabolismo , Tromboembolia Venosa/etiología , Animales , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Femenino , Humanos , Masculino , Ratones , Ratones Desnudos , Transducción de Señal , Triptófano/metabolismo , Tromboembolia Venosa/metabolismo , Tromboembolia Venosa/patología , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Sci Rep ; 9(1): 20257, 2019 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-31882749

RESUMEN

Casitas B lymphoma (c-Cbl) is an E3 ubiquitin ligase and a negative regulator of colorectal cancer (CRC). Despite its high expression in immune cells, the effect of c-Cbl on the tumor microenvironment remains poorly understood. Here we demonstrate that c-Cbl alters the tumor microenvironment and suppresses Programmed cell death-1 (PD-1) protein, an immune checkpoint receptor. Using syngeneic CRC xenografts, we observed significantly higher growth of xenografts and infiltrating immune cells in c-Cbl+/- compared to c-Cbl+/+ mice. Tumor-associated CD8+ T-lymphocytes and macrophages of c-Cbl+/- mice showed 2-3-fold higher levels of PD-1. Functionally, macrophages from c-Cbl+/- mice showed a 4-5-fold reduction in tumor phagocytosis, which was restored with an anti-PD-1 neutralizing antibody suggesting regulation of PD-1 by c-Cbl. Further mechanistic probing revealed that C-terminus of c-Cbl interacted with the cytoplasmic tail of PD-1. c-Cbl destabilized PD-1 through ubiquitination- proteasomal degradation depending on c-Cbl's RING finger function. This data demonstrates c-Cbl as an E3 ligase of PD-1 and a regulator of tumor microenvironment, both of which were unrecognized components of its tumor suppressive activity. Advancing immune checkpoint and c-Cbl biology, our study prompts for probing of PD-1 regulation by c-Cbl in conditions driven by immune checkpoint abnormalities such as cancers and autoimmune diseases.


Asunto(s)
Linfocitos T CD8-positivos/metabolismo , Neoplasias Colorrectales/genética , Receptor de Muerte Celular Programada 1/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Proto-Oncogénicas c-cbl/genética , Ubiquitina-Proteína Ligasas/genética , Animales , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica , Humanos , Macrófagos/metabolismo , Ratones Noqueados , Fosforilación , Receptor de Muerte Celular Programada 1/metabolismo , Proteínas Proto-Oncogénicas c-cbl/metabolismo , Carga Tumoral/genética , Microambiente Tumoral/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
19.
Int Urol Nephrol ; 51(12): 2255-2265, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31646460

RESUMEN

Kidney injury molecule-1 (KIM-1) staining has been shown to be very useful in identifying acute proximal tubular injury, but its sensitivity, specificity and predicting values for the recovery of renal function after injury in renal biopsies have not been well established. In the first study, we randomly selected 184 renal biopsies from a wide age range of patients (children to elderly) with various renal diseases. KIM-1 staining scores were significantly correlated with serum creatinine (sCr) levels (P < 0.05) in all age groups. Receiver-operating characteristic curve (ROC) was generated to evaluate true-positive rate (sensitivity) and true-negative rate (1-specificity). The area under the curve (AUC) in pediatric cases was 0.74, which demonstrated KIM-1 was a fair index in correlating with sCr. In adults, the AUC was 0.87, indicating that KIM-1 was an even better index in the adult population in correlating to sCr. The second study was to determine whether KIM-1 could be a potential predictor of the recovery of acute kidney injury (AKI), and 51 indicated native biopsies with acute tubular injury were randomly selected for KIM-1 staining and sCr follow-up over a 6-month period. A higher KIM-1/sCr ratio (0.57 ± 0.06) was significantly and positively associated with a better reduction in sCr over 6 months. In summary, our data demonstrated that KIM-1 staining in renal biopsies is a sensitive and specific marker to identify acute tubular injury and KIM-1/sCr ratio is useful for predicting the recovery of renal function after injury, although some patients' sCr levels cannot return to their baseline levels.


Asunto(s)
Lesión Renal Aguda/patología , Receptor Celular 1 del Virus de la Hepatitis A/análisis , Túbulos Renales , Riñón/química , Riñón/patología , Lesión Renal Aguda/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , Biopsia , Creatinina/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reacción del Ácido Peryódico de Schiff , Valor Predictivo de las Pruebas , Recuperación de la Función , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
20.
Biology (Basel) ; 8(4)2019 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-31561587

RESUMEN

This paper adopts the Design-Expert software to design an orthogonal experiment with a pulse voltage amplitude of 30 kV, processing time of three minutes, and a pulse width of 45 µs as the center points, in order to study the effects of the pulsed electric field on the cell wall and infection activity of Rhizoctonia solani. High-voltage pulse power was used to treat the bacteria solution with the pulsed electric field. Untreated Rhizoctonia solani were used as the control group. Transmission electron microscope images were used to analyze the cell wall damage. ANOVA was performed on the experimental results and the fitting degree of the model was good (F>>1). Response surface analysis was used to optimize the parameters based on chitin content and polygalacturonase activity. The optimal treatment conditions were obtained as a pulse voltage amplitude of 25 kV, processing time of 2.54 min, and a pulse width of 34.35 µs. On this basis, experiments were designed to verify the optimized conditions. The results demonstrated that, under the optimal processing conditions, the damage index of the cell wall of Rhizoctonia solani was 9.59% lower in chitin content and 83.05% lower in polygalacturonase activity compared with those of the control group. All indexes were significantly different (P < 0.001), which is consistent with the parameter optimization results. The results provide a theoretical basis for the pulsed electric field assisted sterilization and reference for the design of plant protection machinery in the latter stage.

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