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1.
J Am Chem Soc ; 146(15): 10550-10558, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38584353

RESUMEN

Implementing the synergistic effects between the metal and the ligand has successfully streamlined the energetics for CO2 activation and gained high catalytic activities, establishing the important breakthroughs in photocatalytic CO2 reduction. Herein, we describe a Ni(II) N-confused porphyrin complex (NiNCP) featuring an acidic N-H group. It is readily deprotonated and exists in an anion form during catalysis. Owing to this functional site, NiNCP gave rise to an outstanding turnover number (TON) as high as 217,000 with a 98% selectivity for CO2 reduction to CO, while the parent Ni(II) porphyrin (NiTPP) was found to be nearly inactive. Our mechanistic analysis revealed a nonclassical reaction pattern where CO2 was effectively activated via the attack of the Lewis-basic ligand. The resulting ligand-bound CO2 adduct could be further reduced to produce CO. This new metal-ligand synergistic effect is anticipated to inspire the design of highly active catalysts for small molecule activations.

2.
Am J Physiol Renal Physiol ; 326(1): F20-F29, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37916289

RESUMEN

We have previously shown that the long-acting ß2-adrenergic receptor (ß2-AR) agonist formoterol induced recovery from acute kidney injury in mice. To determine whether formoterol protected against diabetic nephropathy, the most common cause of end-stage kidney disease (ESKD), we used a high-fat diet (HFD), a murine type 2 diabetes model, and streptozotocin, a murine type 1 diabetes model. Following formoterol treatment, there was a marked recovery from and reversal of diabetic nephropathy in HFD mice compared with those treated with vehicle alone at the ultrastructural, histological, and functional levels. Similar results were seen after formoterol treatment in mice receiving streptozotocin. To investigate effects in humans, we performed a competing risk regression analysis with death as a competing risk to examine the association between Veterans with chronic kidney disease (CKD) and chronic obstructive pulmonary disease (COPD), who use ß2-AR agonists, and Veterans with CKD but no COPD, and progression to ESKD in a large national cohort of Veterans with stage 4 CKD between 2011 and 2013. Veterans were followed until 2016 or death. ESKD was defined as the initiation of dialysis and/or receipt of kidney transplant. We found that COPD was associated with a 25.6% reduction in progression from stage 4 CKD to ESKD compared with no COPD after adjusting for age, diabetes, sex, race-ethnicity, comorbidities, and medication use. Sensitivity analysis showed a 33.2% reduction in ESKD in Veterans with COPD taking long-acting formoterol and a 20.8% reduction in ESKD in Veterans taking other ß2-AR agonists compared with those with no COPD. These data indicate that ß2-AR agonists, especially formoterol, could be a treatment for diabetic nephropathy and perhaps other forms of CKD.NEW & NOTEWORTHY Diabetic nephropathy is the most common cause of ESKD. Formoterol, a long-acting ß2-adrenergic receptor (ß2-AR) agonist, reversed diabetic nephropathy in murine models of type 1 and 2 diabetes. In humans, there was an association with protection from progression of CKD in patients with COPD, by means of ß2-AR agonist intake, compared with those without COPD. These data indicate that ß2-AR agonists, especially formoterol, could be a new treatment for diabetic nephropathy and other forms of CKD.


Asunto(s)
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Fallo Renal Crónico , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Animales , Ratones , Nefropatías Diabéticas/tratamiento farmacológico , Agonistas de Receptores Adrenérgicos beta 2/uso terapéutico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Estreptozocina , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Fumarato de Formoterol/uso terapéutico , Fallo Renal Crónico/tratamiento farmacológico , Fallo Renal Crónico/etiología , Receptores Adrenérgicos/uso terapéutico
3.
Am J Physiol Renal Physiol ; 327(1): F61-F76, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38721661

RESUMEN

The exocyst and Ift88 are necessary for primary ciliogenesis. Overexpression of Exoc5 (OE), a central exocyst component, resulted in longer cilia and enhanced injury recovery. Mitochondria are involved in acute kidney injury (AKI). To investigate cilia and mitochondria, basal respiration and mitochondrial maximal and spare respiratory capacity were measured in Exoc5 OE, Exoc5 knockdown (KD), Exoc5 ciliary targeting sequence mutant (CTS-mut), control Madin-Darby canine kidney (MDCK), Ift88 knockout (KO), and Ift88 rescue cells. In Exoc5 KD, Exoc5 CTS-mut, and Ift88 KO cells, these parameters were decreased. In Exoc5 OE and Ift88 rescue cells they were increased. Reactive oxygen species were higher in Exoc5 KD, Exoc5 CTS-mut, and Ift88 KO cells compared with Exoc5 OE, control, and Ift88 rescue cells. By electron microscopy, mitochondria appeared abnormal in Exoc5 KD, Exoc5 CTS-mut, and Ift88 KO cells. A metabolomics screen of control, Exoc5 KD, Exoc5 CTS-mut, Exoc5 OE, Ift88 KO, and Ift88 rescue cells showed a marked increase in tryptophan levels in Exoc5 CTS-mut (113-fold) and Exoc5 KD (58-fold) compared with control cells. A 21% increase was seen in Ift88 KO compared with rescue cells. In Exoc5 OE compared with control cells, tryptophan was decreased 59%. To determine the effects of ciliary loss on AKI, we generated proximal tubule-specific Exoc5 and Ift88 KO mice. These mice had loss of primary cilia, decreased mitochondrial ATP synthase, and increased tryptophan in proximal tubules with greater injury following ischemia-reperfusion. These data indicate that cilia-deficient renal tubule cells are primed for injury with mitochondrial defects in tryptophan metabolism.NEW & NOTEWORTHY Mitochondria are centrally involved in acute kidney injury (AKI). Here, we show that cilia-deficient renal tubule cells both in vitro in cell culture and in vivo in mice are primed for injury with mitochondrial defects and aberrant tryptophan metabolism. These data suggest therapeutic strategies such as enhancing ciliogenesis or improving mitochondrial function to protect patients at risk for AKI.


Asunto(s)
Lesión Renal Aguda , Cilios , Mitocondrias , Triptófano , Animales , Cilios/metabolismo , Cilios/patología , Mitocondrias/metabolismo , Mitocondrias/patología , Perros , Triptófano/metabolismo , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Lesión Renal Aguda/genética , Células de Riñón Canino Madin Darby , Especies Reactivas de Oxígeno/metabolismo , Túbulos Renales/metabolismo , Túbulos Renales/patología , Ratones , Proteínas Supresoras de Tumor/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/deficiencia , Ratones Noqueados
4.
BMC Med ; 22(1): 171, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38649992

RESUMEN

BACKGROUND: Little is known about the safety and efficacy of discontinuing antiplatelet therapy via LMWH bridging therapy in elderly patients with coronary stents implanted for > 12 months undergoing non-cardiac surgery. This randomized trial was designed to compare the clinical benefits and risks of antiplatelet drug discontinuation via LMWH bridging therapy. METHODS: Patients were randomized 1:1 to receive subcutaneous injections of either dalteparin sodium or placebo. The primary efficacy endpoint was cardiac or cerebrovascular events. The primary safety endpoint was major bleeding. RESULTS: Among 2476 randomized patients, the variables (sex, age, body mass index, comorbidities, medications, and procedural characteristics) and percutaneous coronary intervention information were not significantly different between the bridging and non-bridging groups. During the follow-up period, the rate of the combined endpoint in the bridging group was significantly lower than in the non-bridging group (5.79% vs. 8.42%, p = 0.012). The incidence of myocardial injury in the bridging group was significantly lower than in the non-bridging group (3.14% vs. 5.19%, p = 0.011). Deep vein thrombosis occurred more frequently in the non-bridging group (1.21% vs. 0.4%, p = 0.024), and there was a trend toward a higher rate of pulmonary embolism (0.32% vs. 0.08%, p = 0.177). There was no significant difference between the groups in the rates of acute myocardial infarction (0.81% vs. 1.38%), cardiac death (0.24% vs. 0.41%), stroke (0.16% vs. 0.24%), or major bleeding (1.22% vs. 1.45%). Multivariable analysis showed that LMWH bridging, creatinine clearance < 30 mL/min, preoperative hemoglobin < 10 g/dL, and diabetes mellitus were independent predictors of ischemic events. LMWH bridging and a preoperative platelet count of < 70 × 109/L were independent predictors of minor bleeding events. CONCLUSIONS: This study showed the safety and efficacy of perioperative LMWH bridging therapy in elderly patients with coronary stents implanted > 12 months undergoing non-cardiac surgery. An alternative approach might be the use of bridging therapy with half-dose LMWH. TRIAL REGISTRATION: ISRCTN65203415.


Asunto(s)
Stents , Humanos , Masculino , Femenino , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/uso terapéutico , Inhibidores de Agregación Plaquetaria/efectos adversos , Heparina de Bajo-Peso-Molecular/administración & dosificación , Heparina de Bajo-Peso-Molecular/uso terapéutico , Heparina de Bajo-Peso-Molecular/efectos adversos , Dalteparina/administración & dosificación , Dalteparina/uso terapéutico , Dalteparina/efectos adversos , Resultado del Tratamiento , Procedimientos Quirúrgicos Operativos/efectos adversos , Hemorragia/inducido químicamente , Placebos/administración & dosificación , Atención Perioperativa/métodos
5.
Small ; 20(28): e2312020, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38326093

RESUMEN

Artificial photocatalytic CO2 reduction (CO2R) holds great promise to directly store solar energy into chemical bonds. The slow charge and mass transfer kinetics at the triphasic solid-liquid-gas interface calls for the rational design of heterogeneous photocatalysts concertedly boosting interfacial charge transfer, local CO2 concentration, and exposure of active sites. To meet these requirements, in this study heterostructures of CdS/MOL (MOL = metal-organic layer) furnishing different redox Co sites are fabricated for CO2R photocatalysts. It is found that the coordination environment of Co is key to photocatalytic activity. The best catalyst ensemble comprising ligand-chelated Co2+ with the bipyridine electron mediator demonstrates a high CO yield rate of 1523 µmol h-1 gcat -1, selectivity of 95.8% and TON of 1462.4, which are ranked among the best seen in literature. Comprehensive photochemical and electroanalytical characterizations attribute the high CO2R performance to the improved photocarrier separation and charge kinetics originated from the proper energy band alignment and coordination chemistry. This work highlights the construction of 2D heterostructures and modulation of transition metal coordination to expedite the charge kinetics in photocatalytic CO2 reduction.

6.
BMC Geriatr ; 24(1): 540, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38907213

RESUMEN

BACKGROUND: Perioperative myocardial injury/infarction (PMI) following noncardiac surgery is a frequent cardiac complication. This study aims to evaluate PMI risk and explore preoperative assessment tools of PMI in patients at increased cardiovascular (CV) risk who underwent noncardiac surgery under the surgical and medical co-management (SMC) model. METHODS: A prospective cohort study that included consecutive patients at increased CV risk who underwent intermediate- or high-risk noncardiac surgery at the Second Medical Center, Chinese PLA General Hospital, between January 2017 and December 2022. All patients were treated with perioperative management by the SMC team. The SMC model was initiated when surgical intervention was indicated and throughout the entire perioperative period. The incidence, risk factors, and impact of PMI on 30-day mortality were analyzed. The ability of the Revised Cardiac Risk Index (RCRI), frailty, and their combination to predict PMI was evaluated. RESULTS: 613 eligible patients (mean [standard deviation, SD] age 73.3[10.9] years, 94.6% male) were recruited consecutively. Under SMC, PMI occurred in 24/613 patients (3.9%). Patients with PMI had a higher rate of 30-day mortality than patients without PMI (29.2% vs. 0.7%, p = 0.00). The FRAIL Scale for frailty was independently associated with an increased risk for PMI (odds ratio = 5.91; 95% confidence interval [CI], 2.34-14.93; p = 0.00). The RCRI demonstrated adequate discriminatory capacity for predicting PMI (area under the curve [AUC], 0.78; 95% CI, 0.67-0.88). Combining frailty with the RCRI further increased the accuracy of predicting PMI (AUC, 0.87; 95% CI, 0.81-0.93). CONCLUSIONS: The incidence of PMI was relatively low in high CV risk patients undergoing intermediate- or high-risk noncardiac surgery under SMC. The RCRI adequately predicted PMI. Combining frailty with the RCRI further increased the accuracy of PMI predictions, achieving excellent discriminatory capacity. These findings may aid personalized evaluation and management of high-risk patients who undergo intermediate- or high-risk noncardiac surgery.


Asunto(s)
Infarto del Miocardio , Complicaciones Posoperatorias , Humanos , Masculino , Femenino , Anciano , Estudios Prospectivos , Infarto del Miocardio/epidemiología , Infarto del Miocardio/diagnóstico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Medición de Riesgo/métodos , Factores de Riesgo , Procedimientos Quirúrgicos Operativos/efectos adversos , Persona de Mediana Edad , Incidencia , Anciano de 80 o más Años , Fragilidad/epidemiología , Fragilidad/diagnóstico , China/epidemiología
7.
Angew Chem Int Ed Engl ; 62(28): e202305558, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37173611

RESUMEN

Silicon semiconductor functionalized with molecular catalysts emerges as a promising cathode for photoelectrochemical (PEC) CO2 reduction reaction (CO2 RR). However, the limited kinetics and stabilities remains a major hurdle for the development of such composites. We herein report an assembling strategy of silicon photocathodes via chemically grafting a conductive graphene layer onto the surface of n+ -p Si followed by catalyst immobilization. The covalently-linked graphene layer effectively enhances the photogenerated carriers transfer between the cathode and the reduction catalyst, and improves the operating stability of the electrode. Strikingly, we demonstrate that altering the stacking configuration of the immobilized cobalt tetraphenylporphyrin (CoTPP) catalyst through calcination can further enhance the electron transfer rate and the PEC performance. At the end, the graphene-coated Si cathode immobilized with CoTPP catalyst managed to sustain a stable 1-Sun photocurrent of -1.65 mA cm-2 over 16 h for CO production in water at a near neutral potential of -0.1 V vs. reversible hydrogen electrode. This represents a remarkable improvement of PEC CO2 RR performance in contrast to the reported photocathodes functionalized with molecular catalysts.

8.
Nano Lett ; 21(17): 7354-7362, 2021 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-34448389

RESUMEN

The deployment of Li metal batteries has been significantly tethered by uncontrollable lithium dendrite growth, especially in heavy-duty operations. Herein, we implement an in situ surface transformation tactic exploiting the vapor-phase solid-gas reaction to construct an artificial solid-electrolyte interphase (SEI) of Li2Se on Li metal anodes. The conformal Li2Se layer with high ionic diffusivity but poor electron conductivity effectively restrains the Li/Li+ redox conversion to the Li/Li2Se interface, and further renders a smooth and chunky Li deposition through homogenized Li+ flux and promoted redox kinetics. Consequently, the as-fabricated Li@Li2Se electrodes demonstrate superb cycling stability in symmetric cells at both high capacity and current density. The merits of inhibited dendrite growth and side reactions on the stabilized Li@Li2Se anode are further manifested in Li-O2 batteries, greatly extending the cycling stability and energy efficiency.

9.
Molecules ; 27(9)2022 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-35566095

RESUMEN

As compared to China's overall oil reserves, the reserve share of offshore oilfields is rather significant. However, offshore oilfield circumstances for enhanced oil recovery (EOR) include not just severe temperatures and salinity, but also restricted space on offshore platforms. This harsh oil production environment requires polymers with relatively strong salt resistance, solubility, thickening ability, rapid, superior injection capabilities, and anti-shearing ability. As a result, research into polymers with high viscosity and quick solubility is recognized as critical to meeting the criteria of polymer flooding in offshore oil reservoirs. For the above purposes, a novel hydrophobically associating polymer (HAP) was prepared to be used for polymer flooding of Bohai offshore oilfields. The synthetic procedure was free radical polymerization in aqueous solutions starting at 0 °C, using acrylamide (AM), acrylic acid (AA), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), and poly(ethylene glycol) octadecyl methacrylate (POM) as comonomers. It was discovered that under ideal conditions, the molecular weight of HAP exceeds 2.1 × 107 g⋅mol-1. In a simulated reservoir environment, HAP has substantially greater solubility, thickening property, and salt resistance than conventional polyacrylamide (HPAM), with equivalent molecular weight. Finally, the injectivity and propagation of the two polymers in porous media were investigated. Compared with HPAM, which has a similar molecular weight, HAP solution with the concentration of 0.175% had a much better oil displacement effect in the porous medium, which can enhance oil recovery by 8.8%. These discoveries have the potential to pave the way for chemical EOR in offshore oilfields.


Asunto(s)
Petróleo , Polímeros , Yacimiento de Petróleo y Gas , Polimerizacion , Polímeros/química , Agua de Mar
10.
Angew Chem Int Ed Engl ; 61(12): e202116291, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-34985828

RESUMEN

The performance of lithium-metal batteries is severely hampered by uncontrollable dendrite growth and volume expansion on the metal anodes. Inspired by the "blockchain" concept in data mining, here we utilize a conductive polymer-filled metal-organic framework (MOF) as the lithium host, in which polypyrrole (PPy) serves as the "chain" to interlink Li "blocks" stored in the MOF pores. While the N-rich PPy guides fast Li+ infiltration/extrusion and serves as the nucleation sites for isotropic Li growth, the MOF pores compartmentalize bulk Li deposition for 3D matrix Li storage, leading to low-barrier and dendrite-free Li plating/stripping with superb Coulombic efficiency. The as-fabricated lithium-metal anodes operate over 700 cycles at 5 mA cm-2 in symmetric cells, and 800 cycles at 1 C in full cells with a per-cycle capacity loss of only 0.017 %. This work might open a new chapter for Li-metal anode construction by introducing the concept of "blockchain" management of Li plating/stripping.

11.
Int J Mol Sci ; 22(10)2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-34064901

RESUMEN

To characterize the mechanisms by which the highly conserved exocyst trafficking complex regulates eye physiology in zebrafish and mice, we focused on Exoc5 (also known as sec10), a central exocyst component. We analyzed both exoc5 zebrafish mutants and retinal pigmented epithelium (RPE)-specific Exoc5 knockout mice. Exoc5 is present in both the non-pigmented epithelium of the ciliary body and in the RPE. In this study, we set out to establish an animal model to study the mechanisms underlying the ocular phenotype and to establish if loss of visual function is induced by postnatal RPE Exoc5-deficiency. Exoc5-/- zebrafish had smaller eyes, with decreased number of melanocytes in the RPE and shorter photoreceptor outer segments. At 3.5 days post-fertilization, loss of rod and cone opsins were observed in zebrafish exoc5 mutants. Mice with postnatal RPE-specific loss of Exoc5 showed retinal thinning associated with compromised visual function and loss of visual photoreceptor pigments. Abnormal levels of RPE65 together with a reduced c-wave amplitude indicate a dysfunctional RPE. The retinal phenotype in Exoc5-/- mice was present at 20 weeks, but was more pronounced at 27 weeks, indicating progressive disease phenotype. We previously showed that the exocyst is necessary for photoreceptor ciliogenesis and retinal development. Here, we report that exoc5 mutant zebrafish and mice with RPE-specific genetic ablation of Exoc5 develop abnormal RPE pigmentation, resulting in retinal cell dystrophy and loss of visual pigments associated with compromised vision. Together, these data suggest that exocyst-mediated signaling in the RPE is required for RPE structure and function, indirectly leading to photoreceptor degeneration.


Asunto(s)
Células Fotorreceptoras/patología , Degeneración Retiniana , Epitelio Pigmentado de la Retina/patología , Proteínas de Transporte Vesicular/fisiología , Trastornos de la Visión/patología , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células Fotorreceptoras/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Trastornos de la Visión/metabolismo , Pez Cebra
12.
J Biol Chem ; 294(17): 6710-6718, 2019 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-30824539

RESUMEN

The exocyst is a highly conserved protein complex found in most eukaryotic cells and is associated with many functions, including protein translocation in the endoplasmic reticulum, vesicular basolateral targeting, and ciliogenesis in the kidney. To investigate the exocyst functions, here we exchanged proline for alanine in the highly conserved VXPX ciliary targeting motif of EXOC5 (exocyst complex component 5), a central exocyst gene/protein, and generated stable EXOC5 ciliary targeting sequence-mutated (EXOC5CTS-m) Madin-Darby canine kidney (MDCK) cells. The EXOC5CTS-m protein was stable and could bind other members of the exocyst complex. Culturing stable control, EXOC5-overexpressing (OE), Exoc5-knockdown (KD), and EXOC5CTS-m MDCK cells on Transwell filters, we found that primary ciliogenesis is increased in EXOC5 OE cells and inhibited in Exoc5-KD and EXOC5CTS-m cells. Growing cells in collagen gels until the cyst stage, we noted that EXOC5-OE cells form mature cysts with single lumens more rapidly than control cysts, whereas Exoc5-KD and EXOC5CTS-m MDCK cells failed to form mature cysts. Adding hepatocyte growth factor to induce tubulogenesis, we observed that EXOC5-OE cell cysts form tubules more efficiently than control MDCK cell cysts, EXOC5CTS-m MDCK cell cysts form significantly fewer tubules than control cell cysts, and Exoc5-KD cysts did not undergo tubulogenesis. Finally, we show that EXOC5 mRNA almost completely rescues the ciliary phenotypes in exoc5-mutant zebrafish, unlike the EXOC5CTS-m mRNA, which could not efficiently rescue the phenotypes. Taken together, these results indicate that the exocyst, acting through the primary cilium, is necessary for renal ciliogenesis, cystogenesis, and tubulogenesis.


Asunto(s)
Cilios/fisiología , Quistes/patología , Túbulos Renales/crecimiento & desarrollo , Riñón/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animales , ADN Complementario/genética , Perros , Técnicas de Silenciamiento del Gen , Humanos , Enfermedades Renales/patología , Células de Riñón Canino Madin Darby , Mutagénesis Sitio-Dirigida , Unión Proteica , Transporte de Proteínas , ARN Mensajero/metabolismo , Proteínas de Transporte Vesicular/genética , Pez Cebra
13.
Circulation ; 140(16): 1331-1341, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31387361

RESUMEN

BACKGROUND: Bicuspid aortic valve (BAV) disease is a congenital defect that affects 0.5% to 1.2% of the population and is associated with comorbidities including ascending aortic dilation and calcific aortic valve stenosis. To date, although a few causal genes have been identified, the genetic basis for the vast majority of BAV cases remains unknown, likely pointing to complex genetic heterogeneity underlying this phenotype. Identifying genetic pathways versus individual gene variants may provide an avenue for uncovering additional BAV causes and consequent comorbidities. METHODS: We performed genome-wide association Discovery and Replication Studies using cohorts of 2131 patients with BAV and 2728 control patients, respectively, which identified primary cilia genes as associated with the BAV phenotype. Genome-wide association study hits were prioritized based on P value and validated through in vivo loss of function and rescue experiments, 3-dimensional immunohistochemistry, histology, and morphometric analyses during aortic valve morphogenesis and in aged animals in multiple species. Consequences of these genetic perturbations on cilia-dependent pathways were analyzed by Western and immunohistochemistry analyses, and assessment of aortic valve and cardiac function were determined by echocardiography. RESULTS: Genome-wide association study hits revealed an association between BAV and genetic variation in human primary cilia. The most associated single-nucleotide polymorphisms were identified in or near genes that are important in regulating ciliogenesis through the exocyst, a shuttling complex that chaperones cilia cargo to the membrane. Genetic dismantling of the exocyst resulted in impaired ciliogenesis, disrupted ciliogenic signaling and a spectrum of cardiac defects in zebrafish, and aortic valve defects including BAV, valvular stenosis, and valvular calcification in murine models. CONCLUSIONS: These data support the exocyst as required for normal ciliogenesis during aortic valve morphogenesis and implicate disruption of ciliogenesis and its downstream pathways as contributory to BAV and associated comorbidities in humans.


Asunto(s)
Estenosis de la Válvula Aórtica/patología , Válvula Aórtica/anomalías , Cilios/fisiología , Cardiopatías Congénitas/patología , Enfermedades de las Válvulas Cardíacas/patología , Animales , Válvula Aórtica/metabolismo , Válvula Aórtica/patología , Estenosis de la Válvula Aórtica/genética , Enfermedad de la Válvula Aórtica Bicúspide , Estudios de Casos y Controles , Cilios/patología , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genotipo , Cardiopatías Congénitas/genética , Enfermedades de las Válvulas Cardíacas/genética , Enfermedades de las Válvulas Cardíacas/metabolismo , Humanos , Ratones , Ratones Noqueados , Polimorfismo de Nucleótido Simple , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Pez Cebra , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
14.
J Biol Chem ; 292(36): 14814-14826, 2017 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-28729419

RESUMEN

We previously have shown that the highly conserved eight-protein exocyst trafficking complex is required for ciliogenesis in kidney tubule cells. We hypothesized here that ciliogenic programs are conserved across organs and species. To determine whether renal primary ciliogenic programs are conserved in the eye, and to characterize the function and mechanisms by which the exocyst regulates eye development in zebrafish, we focused on exoc5, a central component of the exocyst complex, by analyzing both exoc5 zebrafish mutants, and photoreceptor-specific Exoc5 knock-out mice. Two separate exoc5 mutant zebrafish lines phenocopied exoc5 morphants and, strikingly, exhibited a virtual absence of photoreceptors, along with abnormal retinal development and cell death. Because the zebrafish mutant was a global knockout, we also observed defects in several ciliated organs, including the brain (hydrocephalus), heart (cardiac edema), and kidney (disordered and shorter cilia). exoc5 knockout increased phosphorylation of the regulatory protein Mob1, consistent with Hippo pathway activation. exoc5 mutant zebrafish rescue with human EXOC5 mRNA completely reversed the mutant phenotype. We accomplished photoreceptor-specific knockout of Exoc5 with our Exoc5 fl/fl mouse line crossed with a rhodopsin-Cre driver line. In Exoc5 photoreceptor-specific knock-out mice, the photoreceptor outer segment structure was severely impaired at 4 weeks of age, although a full-field electroretinogram indicated a visual response was still present. However, by 6 weeks, visual responses were eliminated. In summary, we show that ciliogenesis programs are conserved in the kidneys and eyes of zebrafish and mice and that the exocyst is necessary for photoreceptor ciliogenesis and retinal development, most likely by trafficking cilia and outer-segment proteins.


Asunto(s)
Cilios/metabolismo , Exocitosis , Células Fotorreceptoras de Vertebrados/metabolismo , Retina/metabolismo , Animales , Ratones , Ratones Endogámicos C57BL , Mutación , Células Fotorreceptoras de Vertebrados/patología , Retina/patología , Proteínas de Transporte Vesicular/deficiencia , Proteínas de Transporte Vesicular/metabolismo , Pez Cebra
15.
Lasers Med Sci ; 32(2): 397-403, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28013415

RESUMEN

In this study, we aimed to evaluate the impact of preoperative anemia (PA) on oncological outcomes among patients with non-muscle-invasive bladder cancer (NMIBC) treated with GreenLight laser vaporization of bladder tumor (PV-BT). Between January 2010 and December 2015, 407 patients with NMIBC who underwent PV-BT surgery were stratified into normal and anemia groups based on the World Health Organization classification (anemia cutoff value: hemoglobin level, <13.0 m g/dL in men and <12.0 mg/dL in women). The Student's t test and chi-square test were performed to assess the effects of PA on clinical and pathological characteristics of patients with NMIBC. The Kaplan-Meier method was used to investigate the influence of PA on oncological survival outcomes. Before PV-BT, 139 patients (34.2%) were anemic. No significant differences in age, sex, smoking habit, tumor size, focality, grade, and stage were found between the anemia and normal groups. At a median follow-up period of 32.5 months (range, 8-60 months), 74 patients (18.2%) had urothelial recurrence, 30 (7.4%) died from any cause, and 21 (5.2%) died from bladder cancer. In the Kaplan-Meier analysis, preoperative anemia was significantly associated with decreased cancer-specific survival (CSS) and overall survival (OS) of the patients with NMIBC. However, recurrence-free survival (RFS) showed no statistically significant difference between the PA and normal groups. The preoperative anemic patients with NMIBC who underwent PV-BT surgery had worse CSS and OS. PA can be a useful and cost-effective prognostic marker in the clinical practice for NMIBC treatment.


Asunto(s)
Anemia/complicaciones , Terapia por Láser/métodos , Músculos/patología , Cuidados Preoperatorios , Neoplasias de la Vejiga Urinaria/complicaciones , Neoplasias de la Vejiga Urinaria/cirugía , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia/patología , Pronóstico , Neoplasias de la Vejiga Urinaria/patología
16.
Lasers Med Sci ; 32(4): 895-901, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28293871

RESUMEN

The purpose of this study is to assess the safety and efficacy of GreenLight laser photoselective vaporization of the prostate (PVP) for the treatment of benign prostate hyperplasia/lower urinary tract symptoms (BPH/LUTS) in patients with different post-void residual urine (PVR). BPH/LUTS patients treated with PVP from January 2014 to January 2016 were enrolled in the present study. All patients were divided into PVR > 50, 50 ≤ PVR < 400, and PVR ≥ 400 ml groups, and standard general and urological methods for BPH/LUTS were carried out. PVP surgery was performed, and the follow-up outcome was investigated 6 months after surgery. A total of 429 patients were included, and there were no significant differences in comorbid diseases or habits among the three groups. The maximum urinary flow rate (Qmax) differed significantly among the groups (P < 0.001), while patients in the PVR < 50 ml group had higher maximum detrusor pressure (Pdet.max) level than the other two groups (P < 0.001). Patients in 50 ≤ PVR < 400 (P < 0.001) and PVR ≥ 400 (P < 0.001) ml groups were more likely to develop detrusor underactivity than those in the PVR < 50 ml group. All patients were treated with PVP, and there were no severe complications requiring rehospitalization or reoperation except nine designed re-treatments. Follow-up data of 387 patients were available. Significant improvement in outcome parameters (International Prostate Symptom Score [IPSS], Qmax, and PVR) was observed in comparison with baseline measurements for the three groups. PVP significantly improved the IPSS, Qmax, and PVR in patients with different PVR; PVP is a safe and effective procedure for BPH/LUTS patients.


Asunto(s)
Terapia por Láser/métodos , Síntomas del Sistema Urinario Inferior/cirugía , Hiperplasia Prostática/cirugía , Retención Urinaria/cirugía , Anciano , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Resección Transuretral de la Próstata/métodos , Resultado del Tratamiento , Retención Urinaria/etiología
17.
Proc Natl Acad Sci U S A ; 109(9): 3576-81, 2012 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-22323601

RESUMEN

Patterning of the floral organs is exquisitely controlled and executed by four classes of homeotic regulators. Among these, the class B and class C floral homeotic regulators are of central importance as they specify the male and female reproductive organs. Inappropriate induction of the class B gene APETALA3 (AP3) and the class C gene AGAMOUS (AG) causes reduced reproductive fitness and is prevented by polycomb repression. At the onset of flower patterning, polycomb repression needs to be overcome to allow induction of AP3 and AG and formation of the reproductive organs. We show that the SWI2/SNF2 chromatin-remodeling ATPases SPLAYED (SYD) and BRAHMA (BRM) are redundantly required for flower patterning and for the activation of AP3 and AG. The SWI2/SNF2 ATPases are recruited to the regulatory regions of AP3 and AG during flower development and physically interact with two direct transcriptional activators of class B and class C gene expression, LEAFY (LFY) and SEPALLATA3 (SEP3). SYD and LFY association with the AP3 and AG regulatory loci peaks at the same time during flower patterning, and SYD binding to these loci is compromised in lfy and lfy sep3 mutants. This suggests a mechanism for SWI2/SNF2 ATPase recruitment to these loci at the right stage and in the correct cells. SYD and BRM act as trithorax proteins, and the requirement for SYD and BRM in flower patterning can be overcome by partial loss of polycomb activity in curly leaf (clf) mutants, implicating the SWI2/SNF2 chromatin remodelers in reversal of polycomb repression.


Asunto(s)
Proteína AGAMOUS de Arabidopsis/biosíntesis , Adenosina Trifosfatasas/fisiología , Proteínas de Arabidopsis/fisiología , Arabidopsis/fisiología , Flores/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Homeodominio/fisiología , Proteínas de Dominio MADS/biosíntesis , Proteínas Represoras/antagonistas & inhibidores , Factores de Transcripción/fisiología , Proteína AGAMOUS de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Arabidopsis/biosíntesis , Proteínas de Arabidopsis/genética , Ensamble y Desensamble de Cromatina , Flores/ultraestructura , Proteínas de Dominio MADS/genética , Proteínas del Grupo Polycomb , Mapeo de Interacción de Proteínas , Transcripción Genética
18.
Inorg Chem ; 53(12): 6042-7, 2014 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-24895837

RESUMEN

Five heterometallic 3d-4f coordination polymers based on 1,4,7-triazacyclononane-1,4,7-triyl-tris(methylenephosphonic acid) (notpH6) are reported. Compounds [FeLn(notpH)(H2O)4]ClO4·5H2O [Ln = Nd (FeNd), Gd (FeGd), Sm (FeSm), Eu (FeEu)] are isostructural. All show layer structures in which the Fe(notpH)(2-) unit serves as a metalloligand to link four equivalent Ln(III) ions into a layer. Compound [CuLa(notpH2)(H2O)2]ClO4·3H2O (CuLa) displays a chain structure, where the Cu(notpH2)(2-) unit connects the La(III) ions into a chain. The magnetic properties of FeLn are studied.

19.
Int J Nanomedicine ; 19: 5317-5333, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38859953

RESUMEN

Purpose: The purpose of this study is to address the high mortality and poor prognosis associated with Acute Respiratory Distress Syndrome (ARDS), conditions characterized by acute and progressive respiratory failure. The primary goal was to prolong drug circulation time, increase drug accumulation in the lungs, and minimize drug-related side effects. Methods: Simvastatin (SIM) was used as the model drug in this study. Employing a red blood cell surface-loaded nanoparticle drug delivery technique, pH-responsive cationic nanoparticles loaded with SIM were non-covalently adsorbed onto the surface of red blood cells (RBC), creating a novel drug delivery system (RBC@SIM-PEI-PPNPs). Results: The RBC@SIM-PEI-PPNPs delivery system effectively extended the drug's circulation time, providing an extended therapeutic window. Additionally, this method substantially improved the targeted accumulation of SIM in lung tissues, thereby enhancing the drug's efficacy in treating ARDS and impeding its progression to ARDS. Crucially, the system showed a reduced risk of adverse drug reactions. Conclusion: RBC@SIM-PEI-PPNPs demonstrates promise in ARDS and ARDS treatment. This innovative approach successfully overcomes the limitations associated with SIM's poor solubility and low bioavailability, resulting in improved therapeutic outcomes and fewer drug-related side effects. This research holds significant clinical implications and highlights its potential for broader application in drug delivery and lung disease treatment.


Asunto(s)
Eritrocitos , Síndrome de Dificultad Respiratoria , Simvastatina , Simvastatina/administración & dosificación , Simvastatina/farmacocinética , Simvastatina/química , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Eritrocitos/efectos de los fármacos , Animales , Pulmón/efectos de los fármacos , Humanos , Masculino , Sistema de Administración de Fármacos con Nanopartículas/química , Sistema de Administración de Fármacos con Nanopartículas/farmacocinética , Nanopartículas/química , Nanopartículas/administración & dosificación , Ratones , Polietileneimina/química , Sistemas de Liberación de Medicamentos/métodos , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética
20.
J Phys Chem Lett ; : 7342-7350, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38989694

RESUMEN

Electrocatalytic CO2 reduction (eCO2R) in acid holds promise in renewable electricity-powered CO2 utilization with high efficiency, but the hydrogen evolution reaction (HER) often prevails and results in a low eCO2R selectivity. Here, using cobalt phthalocyanine/Ketjen black (CoPc/KB) as the model catalysts, we systematically study the effect of active site density, operational current density, and hydrated cations on the acidic eCO2R selectivity and decipher it through the componential dynamics of electric double layer (EDL). The optimal CoPc-4/KB demonstrates a near-unity CO Faradaic efficiency from 50 to 400 mA cm-2 and superb operational stability (>120 h) at 100 mA cm-2. Aided by in situ Raman and infrared spectroscopies, we reveal that the proper cations establish an electrostatic shield for mitigating bulk H+ penetration and mediate the interfacial water structure for suppressing HER. This study should elicit further profound thinking on robust eCO2R system design from the perspective of multiphasic and dynamic EDL.

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