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1.
Proc Natl Acad Sci U S A ; 121(25): e2310793121, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38861592

RESUMEN

mTORC1 is aberrantly activated in renal cell carcinoma (RCC) and is targeted by rapalogs. As for other targeted therapies, rapalogs clinical utility is limited by the development of resistance. Resistance often results from target mutation, but mTOR mutations are rarely found in RCC. As in humans, prolonged rapalog treatment of RCC tumorgrafts (TGs) led to resistance. Unexpectedly, explants from resistant tumors became sensitive both in culture and in subsequent transplants in mice. Notably, resistance developed despite persistent mTORC1 inhibition in tumor cells. In contrast, mTORC1 became reactivated in the tumor microenvironment (TME). To test the role of the TME, we engineered immunocompromised recipient mice with a resistance mTOR mutation (S2035T). Interestingly, TGs became resistant to rapalogs in mTORS2035T mice. Resistance occurred despite mTORC1 inhibition in tumor cells and could be induced by coculturing tumor cells with mutant fibroblasts. Thus, enforced mTORC1 activation in the TME is sufficient to confer resistance to rapalogs. These studies highlight the importance of mTORC1 inhibition in nontumor cells for rapalog antitumor activity and provide an explanation for the lack of mTOR resistance mutations in RCC patients.


Asunto(s)
Carcinoma de Células Renales , Resistencia a Antineoplásicos , Neoplasias Renales , Diana Mecanicista del Complejo 1 de la Rapamicina , Serina-Treonina Quinasas TOR , Animales , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/patología , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Ratones , Humanos , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Microambiente Tumoral/efectos de los fármacos , Línea Celular Tumoral , Sirolimus/farmacología , Mutación , Inhibidores mTOR/farmacología , Inhibidores mTOR/uso terapéutico
2.
PLoS Pathog ; 19(3): e1011288, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36972314

RESUMEN

Exocytosis is a key active process in cells by which proteins are released in bulk via the fusion of exocytic vesicles with the plasma membrane. Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein-mediated vesicle fusion with the plasma membrane is essential in most exocytotic pathways. In mammalian cells, the vesicular fusion step of exocytosis is normally mediated by Syntaxin-1 (Stx1) and SNAP25 family proteins (SNAP25 and SNAP23). However, in Toxoplasma gondii, a model organism of Apicomplexa, the only SNAP25 family protein, with a SNAP29-like molecular structure, is involved in vesicular fusion at the apicoplast. Here, we reveal that an unconventional SNARE complex comprising TgStx1, TgStx20, and TgStx21 mediates vesicular fusion at the plasma membrane. This complex is essential for the exocytosis of surface proteins and vesicular fusion at the apical annuli in T. gondii.


Asunto(s)
Toxoplasma , Animales , Toxoplasma/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Membrana Celular/metabolismo , Exocitosis , Fusión de Membrana , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Mamíferos
3.
Exp Cell Res ; 434(2): 113873, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-38092346

RESUMEN

Neurogenic pulmonary edema secondary to acute brain injury (ABI) is a common and fatal disease condition. However, the pathophysiology of brain-lung interactions is incompletely understood. This study aims to investigate whether sympathetic activation-mediated high fluid shear stress after ABI would damage pulmonary endothelial glycocalyx thus leading to increased pulmonary capillary permeability. The tricuspid annular plane systolic excursion (TAPSE) was detected in a rat model of controlled cortical impact (CCI) and CCI + transection of the cervical sympathetic trunk (TCST). Changes in pulmonary capillary permeability were assessed by analyzing the Evans blue, measuring the dry/wet weight ratio of the lungs and altering protein levels in the bronchoalveolar lavage fluid (BALF). The parallel-plate flow chamber system was used to simulate the fluid shear stress in vitro. Western blotting and immunofluorescence staining were used to determine the expression levels of hyaluronan-binding protein (CEMIP), syndecan-1 and tight junction proteins (TJPs, including claudin-5 and occludin). TCST could restrain cardiac overdrive and sympathetic activation in a rat model of CCI. Compared to the CCI group, the CCI + TCST group showed a reduction of CEMPI (which degrades hyaluronic acid), along with an increase of syndecan-1 and TJPs. CCI + TCST group presented decreasing pulmonary capillary permeability. In vitro, high shear stress (HSS) increased the expression of CEMIP and reduced syndecan-1 and TJPs, which was coordinated with the results in vivo. Our findings show that sympathetic activation-mediated high fluid shear stress after ABI would damage pulmonary endothelial glycocalyx thus leading to increased pulmonary capillary permeability.


Asunto(s)
Lesiones Encefálicas , Sindecano-1 , Ratas , Animales , Sindecano-1/metabolismo , Glicocálix/metabolismo , Permeabilidad Capilar , Pulmón/metabolismo , Lesiones Encefálicas/metabolismo
4.
Mol Cell Neurosci ; 128: 103915, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38143048

RESUMEN

BACKGROUND: The EphB receptor tyrosine kinase family participates in intricate signaling pathways that orchestrate neural networks, guide neuronal axon development, and modulate synaptic plasticity through interactions with surface-bound ephrinB ligands. Additionally, Kalirin, a Rho guanine nucleotide exchange factor, is notably expressed in the postsynaptic membrane of excitatory neurons and plays a role in synaptic morphogenesis. This study postulates that Kalirin may act as a downstream effector of EphB3 in epilepsy. This investigation focuses on understanding the link between EphB3 and epilepsy. MATERIALS AND METHODS: Chronic seizure models using LiCl-pilocarpine (LiCl/Pilo) and pentylenetetrazol were developed in rats. Neuronal excitability was gauged through whole-cell patch clamp recordings on rat hippocampal slices. Real-time PCR determined Kalirin's mRNA expression, and Western blotting was employed to quantify EphB3 and Kalirin protein levels. Moreover, dendritic spine density in epileptic rats was evaluated using Golgi staining. RESULTS: Modulation of EphB3 functionality influenced acute seizure severity, latency duration, and frequency of spontaneous recurrent seizures. Golgi staining disclosed an EphB3-driven alteration in dendritic spine density within the hippocampus of epileptic rats, underscoring its pivotal role in the reconfiguration of hippocampal neural circuits. Furthermore, our data propose Kalirin as a prospective downstream mediator of the EphB3 receptor. CONCLUSIONS: Our findings elucidate that EphB3 impacts the action potential dynamics in isolated rat hippocampal slices and alters dendritic spine density in the inner molecular layer of epileptic rat hippocampi, likely through Kalirin-mediated pathways. This hints at EphB3's significant role in shaping excitatory circuit loops and recurrent seizure activity via Kalirin.


Asunto(s)
Epilepsia , Neuronas , Ratas , Animales , Ratas Sprague-Dawley , Estudios Prospectivos , Neuronas/metabolismo , Epilepsia/metabolismo , Convulsiones/metabolismo
5.
Clin Infect Dis ; 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38484128

RESUMEN

BACKGROUND: Oral pre-exposure prophylaxis (PrEP) with emtricitabine/tenofovir disoproxil fumarate (F/TDF) has high efficacy against HIV-1 acquisition. Seventy-two prospective studies of daily oral F/TDF PrEP were conducted to evaluate HIV-1 incidence, drug resistance, adherence, and bone and renal safety in diverse settings. METHODS: HIV-1 incidence was calculated from incident HIV-1 diagnoses after PrEP initiation and within 60 days of discontinuation. Tenofovir concentration in dried blood spots (DBS), drug resistance, and bone/renal safety indicators were evaluated in a subset of studies. RESULTS: Among 17,274 participants, there were 101 cases with new HIV-1 diagnosis (0.77 per 100 person-years; 95% CI 0.63-0.94). In 78 cases with resistance data, 18 (23%) had M184I or V, one (1.3%) had K65R, and three (3.8%) had both mutations. In 54 cases with tenofovir concentration data from DBS, 45 (83.3%), 2 (3.7%), 6 (11.1%), and 1 (1.9%) had average adherence of <2, 2-3, 4-6, and ≥7 doses/week, respectively, and the corresponding incidence was 3.9 (95% CI 2.9-5.3), 0.24 (0.060-0.95), 0.27 (0.12-0.60), and 0.054 (0.008-0.38) per 100 person-years. Adherence was low in younger participants, Hispanic/Latinx and Black participants, cisgender women, and transgender women. Bone and renal adverse event incidence rates were 0.69 and 11.8 per 100 person-years, respectively, consistent with previous reports. CONCLUSIONS: Leveraging the largest pooled analysis of global PrEP studies to date, we demonstrate that F/TDF is safe and highly effective, even with less than daily dosing, in diverse clinical settings, geographies, populations, and routes of HIV-1 exposure.

6.
J Am Chem Soc ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990188

RESUMEN

Single-atom catalysts (SACs) open up new possibilities for advanced technologies. However, a major complication in preparing high-density single-atom sites is the aggregation of single atoms into clusters. This complication stems from the delicate balance between the diffusion and stabilization of metal atoms during pyrolysis. Here, we present pressure-controlled metal diffusion as a new concept for fabricating ultra-high-density SACs. Reducing the pressure inhibits aggregation substantially, resulting in almost three times higher single-atom loadings than those obtained at ambient pressure. Molecular dynamics and computational fluid dynamics simulations reveal the role of a metal hopping mechanism, maximizing the metal atom distribution through an increased probability of metal-ligand binding. The investigation of the active site density by electrocatalytic oxygen reduction validates the robustness of our approach. The first realization of Ullmann-type carbon-oxygen couplings catalyzed on single Cu sites demonstrates further options for efficient heterogeneous catalysis.

7.
Small ; 20(2): e2305508, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37670540

RESUMEN

Single-atom catalysts (SACs) with specific N-coordinated configurations immobilized on the carbon substrates have recently been verified to effectively alleviate the shuttle effect of lithium polysulfides (LiPSs) in lithium-sulfur (Li─S) batteries. Herein, a versatile molten salt (KCl/ZnCl2 )-mediated pyrolysis strategy is demonstrated to fabricate Zn SACs composed of well-defined Zn-N4 sites embedded into porous carbon sheets with rich pyridine-N defects (Zn─N/CS). The electrochemical kinetic analysis and theoretical calculations reveal the critical roles of Zn-N4 active sites and surrounding pyridine-N defects in enhancing adsorption toward LiPS intermediates and catalyzing their liquid-solid conversion. It is confirmed by reducing the overpotential of the rate-determining step of Li2 S2 to Li2 S and the energy barrier for Li2 S decomposition, thus the Zn─N/CS guarantees fast redox kinetics between LiPSs and Li2 S products. As a proof of concept demonstration, the assembled Li─S batteries with the Zn─N/CS-based sulfur cathode deliver a high specific capacity of 1132 mAh g-1 at 0.1 C and remarkable capacity retention of 72.2% over 800 cycles at 2 C. Furthermore, a considerable areal capacity of 6.14 mAh cm-2 at 0.2 C can still be released with a high sulfur loading of 7.0 mg cm-2 , highlighting the practical applications of the as-obtained Zn─N/CS cathode in Li─S batteries.

8.
Small ; : e2401200, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38984748

RESUMEN

Interfacial chemistry plays a crucial role in determining the electrochemical properties of low-temperature rechargeable batteries. Although existing interface engineering has significantly improved the capacity of rechargeable batteries operating at low temperatures, challenges such as sharp voltage drops and poor high-rate discharge capabilities continue to limit their applications in extreme environments. In this study, an energy-level-adaptive design strategy for electrolytes to regulate interfacial chemistry in low-temperature Li||graphite dual-ion batteries (DIBs) is proposed. This strategy enables the construction of robust interphases with superior ion-transfer kinetics. On the graphite cathode, the design endues the cathode interface with solvent/anion-coupled interfacial chemistry, which yields an nitrogen/phosphor/sulfur/fluorin (N/P/S/F)-containing organic-rich interphase to boost anion-transfer kinetics and maintains excellent interfacial stability. On the Li metal anode, the anion-derived interfacial chemistry promotes the formation of an inorganic-dominant LiF-rich interphase, which effectively suppresses Li dendrite growth and improves the Li plating/stripping kinetics at low temperatures. Consequently, the DIBs can operate within a wide temperature range, spanning from -40 to 45 °C. At -40 °C, the DIB exhibits exceptional performance, delivering 97.4% of its room-temperature capacity at 1 C and displaying an extraordinarily high-rate discharge capability with 62.3% capacity retention at 10 C. This study demonstrates a feasible strategy for the development of high-power and low-temperature rechargeable batteries.

9.
Small ; 20(24): e2308304, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38308419

RESUMEN

Lithium-ion batteries (LIBs) has been developed over the last three decades. Increased amount of silicon (Si) is added into graphite anode to increase the energy density of LIBs. However, the amount of Si is limited, due to its structural instability and poor electronic conductivity so a novel approach is needed to overcome these issues. In this work, the synthesized chromium silicide (CrSi2) doped Si nanoparticle anode material achieves an initial capacity of 1729.3 mAh g-1 at 0.2C and retains 1085 mAh g-1 after 500 cycles. The new anode also shows fast charge capability due to the enhanced electronic conductivity provided by CrSi2 dopant, delivering a capacity of 815.9 mAh g-1 at 1C after 1000 cycles with a capacity degradation rate of <0.05% per cycle. An in situ transmission electron microscopy is used to study the structural stability of the CrSi2-doped Si, indicating that the high control of CrSi2 dopant prevents the fracture of Si during lithiation and results in long cycle life. Molecular dynamics simulation shows that CrSi2 doping optimizes the crack propagation path and dissipates the fracture energy. In this work a comprehensive information is provided to study the function of metal ion doping in electrode materials.

10.
Small ; 20(8): e2305991, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37858930

RESUMEN

The application of Si anodes is hindered by some critical issues such as large volume changes of bare Si and fragile solid-electrolyte interface (SEI), resulting in low coulombic efficiency and rapid capacity decay. Herein, a multifunctional SEI film with high content of LiF is in situ constructed via the surface grafting of carbon-fluorine functionalized groups on silicon nanoparticles (SiNPs) during cycling. Mechanical study demonstrates that the incorporation of LiF with high modulus and unbroken carbon-fluorine groups with highly elastic guarantee the rigid-soft coupling SEI film on Si electrode. Furthermore, it is demonstrated that the rigid-soft coupling SEI film can effectively accommodate the volume expansion of Si nanoparticles during lithiation process, with the electrode expanding rate of only 114.16% after 100 cycles (263.87% for bare Si without surface modification). Afterward, with the aid of well-designed rigid-soft coupling SEI, the initial Coulomb efficiency of 89.8% is achieved, showing a reversible capacity of 1477 mAh g-1 after 200 cycles at 1.2 A g-1 . This work provides a simple and efficient solution that can potentially facilitate the practical application of Si anodes.

11.
Cancer Causes Control ; 35(5): 799-815, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38206498

RESUMEN

PURPOSE: One in six incident cancers in the U.S. is a second primary cancer (SPC). Although primary cancers vary considerably by race and ethnicity, little is known about the population-based occurrence of SPC across these groups. METHODS: Using Surveillance, Epidemiology, and End Results (SEER) 12 data and relative to the general population, we calculated standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) for SPC among 2,457,756 Hispanics, non-Hispanic Asian American/Pacific Islanders (NHAAPI), non-Hispanic black (NHB), and non-Hispanic whites (NHW) cancer survivors aged 45 years or older when diagnosed with a first primary cancer (FPC) from 1992 to 2015. RESULTS: The risk of second primary bladder cancer after first primary prostate cancer was higher than expected in Hispanic (SIR = 1.18, 95% CI: 1.01-1.38) and NHAAPI (SIR = 1.41, 95% CI: 1.20-1.65) men than NHB and NHW men. Among women with a primary breast cancer, Hispanic, NHAAPI, and NHB women had a nearly 1.5-fold higher risk of a second primary breast cancer, while NHW women had a 6% lower risk. Among men with prostate cancer whose SPC was diagnosed 2 to <12 months, NHB men were at higher risk for colorectal cancer and Hispanic and NHW men for non-Hodgkin's lymphoma. In the same time frame for breast cancer survivors, Hispanic and NHAAPI women were significantly more likely than NHB and NHW women to be diagnosed with a second primary lung cancer. CONCLUSION: Future studies of SPC should investigate the role of shared etiologies, stage of diagnosis, treatment, and lifestyle factors after cancer survival across different racial and ethnic populations.


Asunto(s)
Etnicidad , Neoplasias Primarias Secundarias , Programa de VERF , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Supervivientes de Cáncer/estadística & datos numéricos , Etnicidad/estadística & datos numéricos , Incidencia , Neoplasias Primarias Secundarias/epidemiología , Neoplasias Primarias Secundarias/etnología , Grupos Raciales/estadística & datos numéricos , Factores de Riesgo , Estados Unidos/epidemiología , Hispánicos o Latinos , Asiático Americano Nativo Hawáiano y de las Islas del Pacífico , Negro o Afroamericano , Blanco
12.
Brief Bioinform ; 23(1)2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-34791021

RESUMEN

The innovation of biotechnologies has allowed the accumulation of omics data at an alarming rate, thus introducing the era of 'big data'. Extracting inherent valuable knowledge from various omics data remains a daunting problem in bioinformatics. Better solutions often need some kind of more innovative methods for efficient handlings and effective results. Recent advancements in integrated analysis and computational modeling of multi-omics data helped address such needs in an increasingly harmonious manner. The development and application of machine learning have largely advanced our insights into biology and biomedicine and greatly promoted the development of therapeutic strategies, especially for precision medicine. Here, we propose a comprehensive survey and discussion on what happened, is happening and will happen when machine learning meets omics. Specifically, we describe how artificial intelligence can be applied to omics studies and review recent advancements at the interface between machine learning and the ever-widest range of omics including genomics, transcriptomics, proteomics, metabolomics, radiomics, as well as those at the single-cell resolution. We also discuss and provide a synthesis of ideas, new insights, current challenges and perspectives of machine learning in omics.


Asunto(s)
Inteligencia Artificial , Aprendizaje Automático , Biología Computacional/métodos , Genómica/métodos , Proteómica/métodos
13.
Plant Physiol ; 192(2): 1569-1583, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-36864608

RESUMEN

Although microRNA408 (miR408) is a highly conserved miRNA, the miR408 response to salt stress differs among plant species. Here, we show that miR408 transcripts are strongly repressed by salt stress and methyl viologen treatment in maize (Zea mays). Application of N, N1-dimethylthiourea partly relieved the NaCl-induced down-regulation of miR408. Transgenic maize overexpressing MIR408b is hypersensitive to salt stress. Overexpression of MIR408b enhanced the rate of net Na+ efflux, caused Na+ to locate in the inter-cellular space, reduced lignin accumulation, and reduced the number of cells in vascular bundles under salt stress. We further demonstrated that miR408 targets ZmLACCASE9 (ZmLAC9). Knockout of MIR408a or MIR408b or overexpression of ZmLAC9 increased the accumulation of lignin, thickened the walls of pavement cells, and improved salt tolerance of maize. Transcriptome profiles of the wild-type and MIR408b-overexpressing transgenic maize with or without salt stress indicated that miR408 negatively regulates the expression of cell wall biogenesis genes under salt conditions. These results indicate that miR408 negatively regulates salt tolerance by regulating secondary cell wall development in maize.


Asunto(s)
Tolerancia a la Sal , Zea mays , Tolerancia a la Sal/genética , Zea mays/metabolismo , Lignina/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Estrés Salino/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
Cardiovasc Diabetol ; 23(1): 233, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965574

RESUMEN

BACKGROUND: Artificial sweeteners are widely popular worldwide as substitutes for sugar or caloric sweeteners, but there are still several important unknowns and controversies regarding their associations with cardiovascular disease (CVD). We aimed to extensively assess the association and subgroup variability between artificial sweeteners and CVD and CVD mortality in the UK Biobank cohort, and further investigate the modification effects of genetic susceptibility and the mediation role of type 2 diabetes mellitus (T2DM). METHODS: This study included 133,285 participants in the UK Biobank who were free of CVD and diabetes at recruitment. Artificial sweetener intake was obtained from repeated 24-hour diet recalls. Cox proportional hazard models were used to estimate HRs. Genetic predisposition was estimated using the polygenic risk score (PRS). Furthermore, time-dependent mediation was performed. RESULTS: In our study, artificial sweetener intake (each teaspoon increase) was significantly associated with an increased risk of incident overall CVD (HR1.012, 95%CI: 1.008,1.017), coronary artery disease (CAD) (HR: 1.018, 95%CI: 1.001,1.035), peripheral arterial disease (PAD) (HR: 1.035, 95%CI: 1.010,1.061), and marginally significantly associated with heart failure (HF) risk (HR: 1.018, 95%CI: 0.999,1.038). In stratified analyses, non-whites were at greater risk of incident overall CVD from artificial sweetener. People with no obesity (BMI < 30 kg/m2) also tended to be at greater risk of incident CVD from artificial sweetener, although the obesity interaction is not significant. Meanwhile, the CVD risk associated with artificial sweeteners is independent of genetic susceptibility, and no significant interaction exists between genetic susceptibility and artificial sweeteners in terms of either additive or multiplicative effects. Furthermore, our study revealed that the relationship between artificial sweetener intake and overall CVD is significantly mediated, in large part, by prior T2DM (proportion of indirect effect: 70.0%). In specific CVD subtypes (CAD, PAD, and HF), the proportion of indirect effects ranges from 68.2 to 79.9%. CONCLUSIONS: Our findings suggest significant or marginally significant associations between artificial sweeteners and CVD and its subtypes (CAD, PAD, and HF). The associations are independent of genetic predisposition and are mediated primarily by T2DM. Therefore, the large-scale application of artificial sweeteners should be prudent, and the responses of individuals with different characteristics to artificial sweeteners should be better characterized to guide consumers' artificial sweeteners consumption behavior.


Asunto(s)
Bancos de Muestras Biológicas , Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Predisposición Genética a la Enfermedad , Humanos , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Reino Unido/epidemiología , Medición de Riesgo , Diabetes Mellitus Tipo 2/mortalidad , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Anciano , Incidencia , Factores de Tiempo , Adulto , Factores de Riesgo , Edulcorantes/efectos adversos , Estudios Prospectivos , Pronóstico , Factores de Riesgo de Enfermedad Cardiaca , Biobanco del Reino Unido
15.
Exp Eye Res ; 239: 109778, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38171475

RESUMEN

Human embryonic stem cell (hESC)- and human induced pluripotent stem cell (hiPSC)-derived retinal pigment epithelium (RPE) therapies are promising alternatives for the treatment of retinal degenerative diseases caused by RPE degeneration. The generation of autologous RPE cells from human adult donors, which has the advantage of avoiding immune rejection and teratoma formation, is an alternative cell resource to gain mechanistic insight into and test potential therapies for RPE degenerative diseases. Here, we found that limbal stem cells (LSCs) from hESCs and adult primary human limbus have the potential to produce RPE cells and corneal stromal stem cells (CSSCs). We showed that hESC-LSC-derived RPE cells (LSC-RPE) expressed RPE markers, had a phagocytic function, and synthesized tropical factors. Furthermore, during differentiation from LSCs to RPE cells, cells became pigmented, accompanied by a decrease in the level of LSC marker KRT15 and an increase in the level of RPE marker MITF. The Wnt signaling pathway plays a role in LSC-RPE fate transition, promotes MITF expression in the nucleus, and encourages RPE fate transition. In addition, we also showed that primary LSCs (pLSCs) from adult human limbus similar to hESC-LSC could generate RPE cells, which was supported by the co-expression of LSC and RPE cell markers (KRT15/OTX2, KRT15/MITF), suggesting the transition from pLSC to RPE cells, and typical polygonal morphology, melanization, RPE cell marker genes expression (TYR, RPE65), tight junction formation by ZO-1 expression, and the most crucial phagocytotic function. On the other hand, both hESC-LSCs and pLSCs also differentiated into CSSCs (LSC-CSSCs) that expressed stem cell markers (PAX6, NESTIN), presented MSC features, including surface marker expression and trilineage differentiation capability, like those in human CSSCs. Furthermore, the capability of pLSC-CSSC to differentiate into cells expressing keratocyte marker genes (ALDH3A1, PTGDS, PDK4) indicated the potential to induce keratocytes. These results suggest that the adult pLSC is an alternative cell resource, and its application provides a novel potential therapeutic avenue for preventing RPE dysfunction-related retinal degenerative diseases and corneal scarring.


Asunto(s)
Células Madre Pluripotentes Inducidas , Células Madre Limbares , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Diferenciación Celular , Células Epiteliales/metabolismo , Pigmentos Retinianos/metabolismo
16.
FASEB J ; 37(12): e23289, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37950635

RESUMEN

Clinically unpredictable retention following fat grafting remains outstanding problems because of the unrevealed mechanism of grafted fat survival. The role of autophagy, a process to maintain cellular homeostasis through recycling cellular debris, has yet been to be reported in fat grafting. This study aims to improve the survival of fat grafting through the autophagy. First, the relationship between cell death and autophagy in the early stage of fat grafting was evaluated through immunostaining, RNA sequencing, and western blot. Next, rapamycin, an autophagic agonist, was used for the culturing of adipose-derived stem cells and adipocytes during ischemia. Cell death, autophagy, and reactive oxygen species (ROS) were assayed. Finally, rapamycin was used to assist fat grafting in nude mice. The results demonstrated that the peak of cell death at the early stage of fat grafting was accompanied by a decrease in autophagy. In vitro, during ischemia, 25 nM was confirmed as the optimal dose of rapamycin that reduces cell death with enhanced autophagy and mitophagy, improved mitochondrial quality as well as decreased ROS accumulation. In vivo, promoted mitophagy, alleviated oxidative stress, and decreased cell apoptosis of rapamycin-treated fat grafts were observed in the early stage. In addition, rapamycin increased the survival of fat grafts with increased neovascularization and reduced fibrosis. We suggested that moderate autophagy induced by rapamycin contribute to enhanced ischemic tolerance and long term survival of fat grafts through mitochondrial quality control.


Asunto(s)
Autofagia , Sirolimus , Ratones , Animales , Especies Reactivas de Oxígeno/metabolismo , Ratones Desnudos , Sirolimus/farmacología , Isquemia , Supervivencia de Injerto , Supervivencia Celular
17.
Vet Res ; 55(1): 79, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886840

RESUMEN

Porcine deltacoronavirus (PDCoV) is an enteropathogenic coronavirus that has been reported to use various strategies to counter the host antiviral innate immune response. The cGAS-STING signalling pathway plays an important role in antiviral innate immunity. However, it remains unclear whether PDCoV achieves immune evasion by regulating the cGAS-STING pathway. Here, we demonstrated that the nonstructural protein 2 (nsp2) encoded by PDCoV inhibits cGAS-STING-mediated type I and III interferon (IFN) responses via the regulation of porcine STING (pSTING) stability. Mechanistically, ectopically expressed PDCoV nsp2 was found to interact with the N-terminal region of pSTING. Consequently, pSTING was degraded through K48-linked ubiquitination and the proteasomal pathway, leading to the disruption of cGAS-STING signalling. Furthermore, K150 and K236 of pSTING were identified as crucial residues for nsp2-mediated ubiquitination and degradation. In summary, our findings provide a basis for elucidating the immune evasion mechanism of PDCoV and will contribute to the development of targets for anti-coronavirus drugs.


Asunto(s)
Deltacoronavirus , Proteínas no Estructurales Virales , Animales , Porcinos , Proteínas no Estructurales Virales/metabolismo , Proteínas no Estructurales Virales/genética , Deltacoronavirus/genética , Deltacoronavirus/fisiología , Enfermedades de los Porcinos/virología , Enfermedades de los Porcinos/inmunología , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Infecciones por Coronavirus/veterinaria , Infecciones por Coronavirus/virología , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/metabolismo , Interferón Tipo I/metabolismo , Interferón Tipo I/genética , Inmunidad Innata , Células HEK293 , Evasión Inmune , Ubiquitinación
18.
BMC Neurol ; 24(1): 243, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009960

RESUMEN

Rheumatoid meningitis (RM) is a rare extra-articular manifestation of rheumatoid arthritis (RA) that has been increasingly recognized by neurologists. However, the diversity of its clinical manifestations makes its diagnosis difficult. RM does not have a unified diagnostic standard, and its link with RA needs to be studied further. Here we report two cases of RM without a history of RA. The first patient, an 80-year-old woman, presented with sudden unilateral limb weakness, with brain MR showing abnormal signals in the leptomeningeal of the right frontal parietal. Subarachnoid hemorrhage was excluded after imaging examination, and infectious meningitis was ruled out after cerebrospinal fluid (CSF) examination. The patient was diagnosed as having RM, she had increased levels of CCP and AKA, the markers of RA, but no history of the disease or other clinical manifestations of it. Another case, a 65-year-old man, was hospitalized with Bell's palsy. We found that he had intracranial imaging changes highly consistent with those characteristic of RM during his routine examination. Except for the left peripheral facial palsy, the patient had no other neurological signs or symptoms and no RA history. After a careful physical examination, we found no joint or other manifestations or serological abnormalities consistent with RA (RF, CCP, AKA, etc.). However, after excluding infection meningitis and considering the patient's unique imaging results, we diagnosed him as having RM. We report these two cases as references for clinical diagnosis and treatment of RM, providing a discussion of our rationale.


Asunto(s)
Artritis Reumatoide , Meningitis , Humanos , Femenino , Artritis Reumatoide/complicaciones , Artritis Reumatoide/diagnóstico , Anciano de 80 o más Años , Meningitis/diagnóstico , Meningitis/complicaciones , Anciano , Masculino , Imagen por Resonancia Magnética
19.
Clin Chem Lab Med ; 62(2): 353-360, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-37746851

RESUMEN

OBJECTIVES: Cardiac troponin (cTn) is the key biomarker for diagnosis of acute coronary syndrome (ACS). We performed a complete assessment of the high-sensitivity cardiac troponin I (hs-cTnI) (CLIA) assay on the analytical performance and clinical diagnostic performance, which was compared with Abbott ARCHITECT hs-cTnI assay. METHODS: Sex-specific 99th percentile upper reference limits (URLs) were determined from a healthy population of 424 males and 408 females. High-sensitivity performance was assessed by examining the imprecision at sex-specific URLs and the detectable results above LoD in a cohort of healthy population. The diagnostic performance of the hs-cTnI (CLIA) assay was validated in a population of 934 patients with suspected ACS. RESULTS: The 99th percentile URLs were 15.3 ng/L for female, 31.3 ng/L for male and 24.2 ng/L for overall population. The total imprecision near the sex-specific 99th percentile URLs were <5 %. 76.74 % of females, 97.12 % of males and 86.69 % of overall population had cTnI values exceeding the LoD, which met the criteria of high-sensitivity troponin assay. No cross-reactivity or interference was identified. The diagnostic sensitivity, specificity, PPV, NPV, and AUC of hs-cTnI (CLIA) assay were 97.97 , 90.70, 79.02, 99.21 % and 0.9885, respectively, which were comparable to ARCHITECT hs-cTnI assay. CONCLUSIONS: hs-cTnI (CLIA) assay is a high-sensitivity troponin I method with high precision, sensitivity and specificity. The clinical diagnostic performance of hs-cTnI (CLIA) is comparable to the established ARCHITECT hs-cTnI assay. Mindray's hs-cTnI (CLIA) assay is an attractive alternative for diagnosis of myocardial infarction with a high level of accuracy and safety.


Asunto(s)
Síndrome Coronario Agudo , Infarto del Miocardio , Humanos , Masculino , Femenino , Troponina I , Sensibilidad y Especificidad , Infarto del Miocardio/diagnóstico , Síndrome Coronario Agudo/diagnóstico , Bioensayo , Biomarcadores , Troponina T
20.
J Nat Prod ; 87(4): 1092-1102, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38557062

RESUMEN

As an important bioactive molecular backbone, drimane meroterpenoids have drawn a great deal of attention from both pharmacologists and chemists. Inspired by the prevalidated success of conformational restriction in the discovery of novel pharmaceutical leads, two distinct tetracyclic drimane meroterpenoids, (-)-pelorol and (+)-aureol, were synthesized from the inexpensive starting material (-)-sclareol through 10 and 8 steps with 5.6% and 5.4% overall yield, respectively. The mild conditions, operational facility, and scalability enabled the expedient synthesis and biological exploration of not only natural products themselves but also their mimics. The first agrochemical exploration showed (-)-pelorol and (+)-aureol possessed good antifungal activity against Rhizoctonia solani, with EC50 values of 7.7 and 6.9 µM, respectively. This revealed that tetracyclic drimane meroterpenoids are valuable models for antifungal lead discovery.


Asunto(s)
Antifúngicos , Rhizoctonia , Antifúngicos/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Estructura Molecular , Rhizoctonia/efectos de los fármacos , Terpenos/farmacología , Terpenos/síntesis química , Terpenos/química , Estereoisomerismo , Sesquiterpenos/farmacología , Sesquiterpenos/síntesis química , Sesquiterpenos/química , Sesquiterpenos Policíclicos/farmacología , Pruebas de Sensibilidad Microbiana
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