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1.
EMBO Rep ; 24(10): e55043, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37551717

RESUMO

The cardiac endothelium influences ventricular chamber development by coordinating trabeculation and compaction. However, the endothelial-specific molecular mechanisms mediating this coordination are not fully understood. Here, we identify the Sox7 transcription factor as a critical cue instructing cardiac endothelium identity during ventricular chamber development. Endothelial-specific loss of Sox7 function in mice results in cardiac ventricular defects similar to non-compaction cardiomyopathy, with a change in the proportions of trabecular and compact cardiomyocytes in the mutant hearts. This phenotype is paralleled by abnormal coronary artery formation. Loss of Sox7 function disrupts the transcriptional regulation of the Notch pathway and connexins 37 and 40, which govern coronary arterial specification. Upon Sox7 endothelial-specific deletion, single-nuclei transcriptomics analysis identifies the depletion of a subset of Sox9/Gpc3-positive endocardial progenitor cells and an increase in erythro-myeloid cell lineages. Fate mapping analysis reveals that a subset of Sox7-null endothelial cells transdifferentiate into hematopoietic but not cardiomyocyte lineages. Our findings determine that Sox7 maintains cardiac endothelial cell identity, which is crucial to the cellular cross-talk that drives ventricular compaction and coronary artery development.


Assuntos
Vasos Coronários , Células Endoteliais , Animais , Camundongos , Vasos Coronários/metabolismo , Células Endoteliais/metabolismo , Miócitos Cardíacos/metabolismo , Regulação da Expressão Gênica , Endotélio/metabolismo , Fatores de Transcrição SOXF/genética , Fatores de Transcrição SOXF/metabolismo
2.
Langmuir ; 40(18): 9688-9701, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38654502

RESUMO

Rubidium (Rb) and cesium (Cs) have important applications in highly technical fields. Salt lakes contain huge reserves of Rb and Cs with industrial significance, which can be utilized after extraction. In this study, a composite magnetic adsorbent (Fe3O4@ZIF-8@AMP, AMP = ammonium phosphomolybdate) was prepared and its adsorption properties for Rb+ and Cs+ were studied in simulated and practical brine. The structure of the adsorbent was characterized by SEM, XRD, N2 adsorption-desorption, FT-IR, and vibrating sample magnetometer (VSM). The adsorbent had good adsorption affinity for Rb+ and Cs+. The Langmuir model and pseudo-second-order dynamics described the adsorbing isotherm and kinetic dates, respectively. The adsorption capacity and adsorption rate of Fe3O4@ZIF-8@AMP were increased by 1.86- and 2.5-fold compared with those of powdered crystal AMP, owing to the large specific surface area and high dispersibility of the adsorbent in the solution. The adsorbent was rapidly separated from the solution within 17 s using an applied magnetic field owing to the good magnetic properties. The composite adsorbent selectively adsorbed Rb+ and Cs+ from the practical brine even in the presence of a large number of coexisting ions. The promising adsorbent can be used to extract Rb+ and Cs+ from aqueous solutions.

3.
Nutr Metab Cardiovasc Dis ; 34(1): 206-213, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37996371

RESUMO

BACKGROUND AND AIMS: Serum uric acid (SUA) has been reported to be associated with inflammation, and elevated SUA is increasingly prevalent in adolescents. The systemic immune-inflammation index (SII) is an innovative and integrated inflammatory indicator that has not yet been studied with SUA in adolescents. We therefore aimed to investigate the potential relationship between SII and SUA in U.S. adolescents. METHODS AND RESULTS: A total of 5,568 adolescents aged 12-19 years from NHANES 2009-2018 were analyzed. SII was calculated as platelet count × neutrophil count/lymphocyte count. Elevated SUA was defined as ≥ 5.5 mg/dL. SII was Ln-transformed for analysis for the skewed distribution. Multivariate linear and multiple logistic regression analyses were conducted to explore the association of SII with SUA and elevated SUA. A generalized additive model and a fitted smoothing curve were also performed. The prevalence of elevated SUA was 35.4 %. Multivariate linear regression analyses indicated that LnSII was positively associated with SUA level (ß = 0.15, 95 % CI: 0.09-0.20). Multiple logistic analyses indicated that LnSII was associated with a 38 % increased risk of elevated SUA (OR = 1.38, 95 % CI: 1.11-1.70). The smooth curve fitting showed that the associations of LnSII with SUA and elevated SUA were linear. Besides, subgroup analyses showed a stronger association between LnSII and SUA in adolescents aged ≥17 years (P for interaction <0.05). CONCLUSIONS: SII was positively associated with SUA level and elevated SUA in U.S. adolescents, particularly in populations aged ≥17 years.


Assuntos
Inflamação , Ácido Úrico , Humanos , Adolescente , Inquéritos Nutricionais , Inflamação/diagnóstico , Inflamação/epidemiologia , Linfócitos , Contagem de Leucócitos
4.
Proc Natl Acad Sci U S A ; 118(43)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34663729

RESUMO

The CO electrooxidation is long considered invincible in the proton exchange membrane fuel cell (PEMFC), where even a trace level of CO in H2 seriously poisons the anode catalysts and leads to huge performance decay. Here, we describe a class of atomically dispersed IrRu-N-C anode catalysts capable of oxidizing CO, H2, or a combination of the two. With a small amount of metal (24 µgmetal⋅cm-2) used in the anode, the H2 fuel cell performs its peak power density at 1.43 W⋅cm-2 When operating with pure CO, this catalyst exhibits its maximum current density at 800 mA⋅cm-2, while the Pt/C-based cell ceases to work. We attribute this exceptional catalytic behavior to the interplay between Ir and Ru single-atom centers, where the two sites act in synergy to favorably decompose H2O and to further facilitate CO activation. These findings open up an avenue to conquer the formidable poisoning issue of PEMFCs.

5.
Exp Eye Res ; 234: 109599, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37488009

RESUMO

Limbal epithelial stem cells are not only critical for corneal epithelial homeostasis but also have the capacity to change from a relatively quiescent mitotic phenotype to a rapidly proliferating cell in response to population depletion following corneal epithelial wounding. Pax6+/- mice display many abnormalities including corneal vascularization and these aberrations are consistent with a limbal stem cell deficiency (LSCD) phenotype. FoxC1 has an inhibitory effect on corneal avascularity and a positive role in stem cell maintenance in many tissues. However, the role of FoxC1 in limbal epithelial stem cells remains unknown. To unravel FoxC1's role(s) in limbal epithelial stem cell homeostasis, we utilized an adeno-associated virus (AAV) vector to topically deliver human FOXC1 proteins into Pax6 +/- mouse limbal epithelium. Under unperturbed conditions, overexpression of FOXC1 in the limbal epithelium had little significant change in differentiation (PAI-2, Krt12) and proliferation (BrdU, Ki67). Conversely, such overexpression resulted in a marked increase in the expression of putative limbal epithelial stem cell markers, N-cadherin and Lrig1. After corneal injuries in Pax6 +/- mice, FOXC1 overexpression enhanced the behavior of limbal epithelial stem cells from quiescence to a highly proliferative status. Overall, the treatment of AAV8-FOXC1 may be beneficial to the function of limbal epithelial stem cells in the context of a deficiency of Pax6 function.


Assuntos
Doenças da Córnea , Epitélio Corneano , Limbo da Córnea , Animais , Humanos , Camundongos , Córnea , Doenças da Córnea/metabolismo , Desbridamento , Células Epiteliais , Epitélio Corneano/metabolismo , Limbo da Córnea/metabolismo , Células-Tronco
6.
Br J Nutr ; 130(12): 2114-2122, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-37424297

RESUMO

Iodine is a vital trace element in the human body and is associated with several important coronary artery disease (CAD) risk factors. We aimed to explore the correlation between urinary iodine concentration (UIC) and CAD. Data from 15 793 US adults in the National Health and Nutrition Examination Survey (2003-2018) were analysed. We conducted multivariable logistic regression models and fitted smoothing curves to study the correlation between UIC and CAD. Furthermore, we performed subgroup analysis to investigate possible effect modifiers between them. We found a J-shaped association between UIC and CAD, with an inflection point at Lg UIC = 2·65 µg/l. This result indicated a neutral association (OR 0·89; 95 % CI 0·68, 1·16) between UIC and CAD as Lg UIC < 2·65 µg/l, but the per natural Lg [UIC] increment was OR 2·29; 95 % CI 1·53, 3·43 as Lg UIC ≥ 2·65 µg/l. An interaction between diabetes and UIC might exist. The increase in UIC results in an increase in CAD prevalence (OR 1·84, 95 % CI 1·32, 2·58) in diabetes but results in little to no difference in non-diabetes (OR 0·98, 95 % CI 0·77, 1·25). The J-shaped correlation between UIC and CAD and the interaction between diabetes and UIC should be confirmed in a prospective study with a series of UIC measurements. If excessive iodine precedes CAD, then this new finding could guide clinical practice and prevent iodine deficiency from being overcorrected.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus , Iodo , Adulto , Humanos , Estados Unidos/epidemiologia , Inquéritos Nutricionais , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/induzido quimicamente , Estudos Prospectivos
7.
Gene Ther ; 29(1-2): 81-93, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34257417

RESUMO

Mutations in the gene for Retinitis Pigmentosa GTPase Regulator (RPGR) cause the X-linked form of inherited retinal degeneration, and the majority are frameshift mutations in a highly repetitive, purine-rich region of RPGR known as the OFR15 exon. Truncation of the reading frame in this terminal exon ablates the functionally important C-terminal domain. We hypothesized that targeted excision in ORF15 by CRISPR/Cas9 and the ensuing repair by non-homologous end joining could restore RPGR reading frame in a portion of mutant photoreceptors thereby correcting gene function in vivo. We tested this hypothesis in the rd9 mouse, a naturally occurring mutant line that carries a frameshift mutation in RPGRORF15, through a combination of germline and somatic gene therapy approaches. In germline gene-edited rd9 mice, probing with RPGR domain-specific antibodies demonstrated expression of full length RPGRORF15 protein. Hallmark features of RPGR mutation-associated early disease phenotypes, such as mislocalization of cone opsins, were no longer present. Subretinal injections of the same guide RNA (sgRNA) carried in AAV sgRNA and SpCas9 expression vectors restored reading frame of RPGRORF15 in a subpopulation of cells with broad distribution throughout the retina, confirming successful correction of the mutation. These data suggest that a simplified form of genome editing mediated by CRISPR, as described here, could be further developed to repair RPGRORF15 mutations in vivo.


Assuntos
Degeneração Retiniana , Retinose Pigmentar , Animais , Sistemas CRISPR-Cas , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Edição de Genes , Camundongos , Mutação , Degeneração Retiniana/genética , Degeneração Retiniana/terapia , Retinose Pigmentar/genética , Retinose Pigmentar/metabolismo , Retinose Pigmentar/terapia
8.
Int J Mol Sci ; 23(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36232661

RESUMO

The adsorption separation and extraction of low-concentration boron from salt-lake brine have great significance. Magnetic separation avoids the problem of adsorbent granulation and improves the usage efficiency. The silicon-based adsorbents have attracted interest due to their superior acid and alkali resistance, in which polyhydroxy graphene enhances the adsorption of boron ions. Herein different boron adsorbents, derived by magnetic separation, were developed and characterized by SEM, TEM, XPS, VSM, FT-IR, and XRD analysis. The adsorption-desorption performance of boron adsorbents with different compositions was evaluated. The isotherms and kinetics parameters of the boron extraction were evaluated based on adsorption-desorption tests. The graphene-based magnetic adsorbent (Go-Fe3O4@SiO2@mSiO2-Glu) registered a high boron adsorption capacity of 23.90 mg/g at pH = 9 in the boron solution and 24.84 mg/g for East Taigener salt-lake brine. The Na+, Mg2+, Ca2+, and Cl- ions have little interference with the boron adsorption. The adsorbents exhibit magnetic separation performance and good cycle life. The results showed that acid-alkali desorption solution has little effect on the adsorbents, and the composite of graphene enhances the adsorption of boron ions. The adsorbents developed in this study are promising to recover boron from low-concentration boron-containing salt-lake brines.


Assuntos
Grafite , Poluentes Químicos da Água , Adsorção , Álcalis , Boro , Glucose , Grafite/química , Cetoácidos , Lagos , Fenômenos Magnéticos , Sais , Silício , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier
9.
BMC Cardiovasc Disord ; 21(1): 452, 2021 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-34537003

RESUMO

BACKGROUND: Light-chain cardiac amyloidosis (AL-CA) has been highly valued in developed countries, but in developing countries, the recognition and diagnosis of this condition is still limited. There are currently few reports on a large number of Chinese patients with AL-CA. The present study aimed to report real-world clinical characteristics and prognosis of AL-CA in China. METHODS AND RESULTS: Consecutive patients with AL-CA diagnosed at the Second Xiangya Hospital of Central South University between June 2012 and September 2020 were reviewed. A total of 170 patients with AL-CA have been recruited, whose mean ages were 60.81 ± 10.46. 70.59% of the patients were male. They were from eight provinces in southern China, 55.7% were referred patients, and 37.3% had been misdiagnosed previously. 64 (37.6%) patients received chemotherapy. The median survival time for patients with AL-CA was 8.00 months, and survival time for patients who received chemotherapy was 13.00 months, which was significantly longer than that of patients with palliative treatment (13.00 vs 6.00, p = 0.004). CONCLUSIONS: Although clinicians have improved their understanding of AL-CA in recent years, the prognosis of AL-CA is still poor, and the misdiagnosis rate and missed diagnosis rate are still very high in China. It is imperative to improve the recognition and early diagnosis of this condition, which may require multidisciplinary collaboration among cardiologists, hematologists and nephrologists.


Assuntos
Cardiomiopatias/diagnóstico , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico , Idoso , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/mortalidade , China , Comorbidade , Diagnóstico Precoce , Feminino , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/tratamento farmacológico , Amiloidose de Cadeia Leve de Imunoglobulina/mortalidade , Masculino , Pessoa de Meia-Idade , Diagnóstico Ausente , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
10.
Int J Med Sci ; 18(15): 3533-3543, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34522180

RESUMO

Importance: Despite the availability of a vaccine against the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), humans will have to live with this virus and the after-effects of the coronavirus disease 2019 (COVID-19) infection for a long time. Cholesterol plays an important role in the infection and prognosis of SARS-CoV-2, and the study of its mechanism is of great significance not only for the treatment of COVID-19 but also for research on generic antiviral drugs. Observations: Cholesterol promotes the development of atherosclerosis by activating NLR family pyrin domain containing 3 (NLRP3), and the resulting inflammatory environment indirectly contributes to COVID-19 infection and subsequent deterioration. In in vitro studies, membrane cholesterol increased the number of viral entry sites on the host cell membrane and the number of angiotensin-converting enzyme 2 (ACE2) receptors in the membrane fusion site. Previous studies have shown that the fusion protein of the virus interacts with cholesterol, and the spike protein of SARS-CoV-2 also requires cholesterol to enter the host cells. Cholesterol in blood interacts with the spike protein to promote the entry of spike cells, wherein the scavenger receptor class B type 1 (SR-B1) plays an important role. Because of the cardiovascular protective effects of lipid-lowering therapy and the additional anti-inflammatory effects of lipid-lowering drugs, it is currently recommended to continue lipid-lowering therapy for patients with COVID-19, but the safety of extremely low LDL-C is questionable. Conclusions and Relevance: Cholesterol can indirectly increase the susceptibility of patients to SARS-CoV-2 and increase the risk of death from COVID-19, which are mediated by NLRP3 and atherosclerotic plaques, respectively. Cholesterol present in the host cell membrane, virus, and blood may also directly participate in the virus cell entry process, but the specific mechanism still needs further study. Patients with COVID-19 are recommended to continue lipid-lowering therapy.


Assuntos
COVID-19/complicações , Hipercolesterolemia/complicações , Enzima de Conversão de Angiotensina 2/metabolismo , Antivirais/uso terapêutico , Aterosclerose/fisiopatologia , COVID-19/diagnóstico , COVID-19/terapia , Membrana Celular/metabolismo , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Endocitose , Humanos , Hipercolesterolemia/diagnóstico , Hipercolesterolemia/terapia , Inflamação , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/sangue , Prognóstico , SARS-CoV-2 , Receptores Depuradores Classe B/metabolismo , Tratamento Farmacológico da COVID-19
11.
Int Heart J ; 62(3): 540-545, 2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-33952805

RESUMO

This study aims to evaluate the impact of the coronavirus disease 2019 (COVID-19) pandemic on patient admissions to Hunan's cardiac intensive care units (CCUs).We conducted a retrospective, single-center study. Data were collected from patients who were confirmed to have critical cardiovascular disease and admitted to the CCU of the Second Xiangya Hospital of Central South University, Hunan, from January 23 to April 23, 2020. Compared with the same period in 2019, the results show that the number of hospitalization decreased by 19.6%; the inhospital mortality rate of CCU was decreased (28.57% versus 16.67%; odds ratio (OR), 0.50; 95% confidence interval (CI), 0.251-0.996; P = 0.047); hospital stay was decreased (7.97 versus 12.36, P < 0.001); hospital emergency percutaneous coronary intervention (PCI) rate in patients with acute coronary syndromes (ACS) significantly decreased (76.00% versus 39.00%, P < 0.001); among this, the PCI rate of patients with ST-segment elevation myocardial infarction (STEMI) decreased (76.32% versus 55.17%, P = 0.028) as well. In addition, the number of patients transferred from other hospitals significantly decreased (76.79% versus 56.67%, P = 0.002), and the number of patients transferred from other cities also decreased by 10.75%.During the outbreak of the COVID-19 epidemic in Hunan Province, the number of patients admitted to CCU decreased, as well as the mortality rate; fewer patients with severe cardiovascular disease can be transported to better hospitals from remote rural areas. In addition to epidemic prevention and control, experts in China should focus on improved emergency transport medical services to reduce this impact.


Assuntos
COVID-19 , Doenças Cardiovasculares/mortalidade , Unidades de Cuidados Coronarianos/tendências , Mortalidade Hospitalar/tendências , Admissão do Paciente/tendências , Transferência de Pacientes/tendências , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/terapia , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos
12.
Lab Invest ; 100(8): 1068-1079, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32341517

RESUMO

Increased permeability and growth (angiogenesis) of blood vessels play a key role in joint swelling and pannus formation in inflammatory arthritis, a family of diseases influenced by reproductive hormones. The hormone prolactin (PRL) protects against joint inflammation, pannus formation, and bone destruction in adjuvant-induced arthritis and these effects may involve its proteolytic conversion to vasoinhibin, a PRL fragment that inhibits angiogenesis and vasopermeability. Here, we show that the intra-articular injection of an adeno-associated virus type-2 (AAV2) vector encoding vasoinhibin reduced joint inflammation, the hyperplasia, vascular density, and vasopermeability of the pannus, and the loss of bone in mice subjected to antigen-induced arthritis. In agreement, the AAV2 vasoinhibin vector reduced the expression of proinflammatory cytokines (interleukin-1ß, interleukin-6), an endothelial cell marker (platelet endothelial cell-adhesion molecule 1), and proangiogenic molecules [vascular endothelial growth factor (VEGF), VEGF receptor 2, and hypoxia-inducible factor 1α] in the arthritic joint. Also, vasoinhibin reduced the synovial vasopermeability induced by the intra-articular injection of VEGF in healthy mice. Finally, vasoinhibin signals by blocking the phosphorylation/activation of endothelial nitric oxide synthase (eNOS) at Ser1179 and the AAV2 vasoinhibin vector inhibited the enhanced phosphorylation of eNOS Ser1179 in the arthritic joint. We conclude that vasoinhibin reduces joint inflammation and bone loss in arthritis by inhibiting pannus angiogenesis and vasopermeability via the blockage of VEGF-induced eNOS activation. These findings suggest the potential therapeutic benefit of AAV2-mediated vasoinhibin gene delivery in arthritis.


Assuntos
Artrite Experimental/terapia , Permeabilidade Capilar/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Osteíte/prevenção & controle , Osteoporose/prevenção & controle , Prolactina/farmacologia , Animais , Antígenos , Artrite Experimental/induzido quimicamente , Artrite Experimental/genética , Proteínas de Ciclo Celular/genética , Dependovirus/genética , Terapia Genética/métodos , Vetores Genéticos/genética , Humanos , Articulações/patologia , Masculino , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Osteíte/genética , Osteíte/terapia , Osteoporose/genética , Osteoporose/terapia
13.
Mol Ther ; 27(7): 1327-1338, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31129118

RESUMO

Primary open-angle glaucoma (POAG) is considered a lifelong disease characterized by optic nerve deterioration and visual field damage. Although the disease progression can usually be controlled by lowering the intraocular pressure (IOP), therapeutic effects of current approaches do not last long. Gene therapy could be a promising method for persistent treatment of the disease. Our previous study demonstrated that gene transfer of exoenzyme C3 transferase (C3) to the trabecular meshwork (TM) to inhibit Rho GTPase (Rho), the upstream signal molecule of Rho-associated kinase (ROCK), resulted in lowered IOP in normal rodent eyes. In the present study, we show that the lentiviral vector (LV)-mediated C3 expression inactivates RhoA in human TM cells by ADP ribosylation, resulting in disruption of the actin cytoskeleton and altered cell morphology. In addition, intracameral delivery of the C3 vector to monkey eyes leads to persistently lowered IOP without obvious signs of inflammation. This is the first report of using a vector to transduce the TM of an alive non-human primate with a gene that alters cellular machinery and physiology. Our results in non-human primates support that LV-mediated C3 expression in the TM may have therapeutic potential for glaucoma, the leading cause of irreversible blindness in humans.


Assuntos
ADP Ribose Transferases/genética , ADP Ribose Transferases/metabolismo , Toxinas Botulínicas/genética , Toxinas Botulínicas/metabolismo , Terapia Genética/métodos , Vetores Genéticos/uso terapêutico , Pressão Intraocular , ADP-Ribosilação/genética , Citoesqueleto de Actina/metabolismo , Animais , Câmara Anterior/metabolismo , Células Cultivadas , Vetores Genéticos/administração & dosagem , Glaucoma de Ângulo Aberto/terapia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Lentivirus , Macaca mulatta , Masculino , Distribuição Tecidual , Malha Trabecular/citologia , Malha Trabecular/metabolismo , Transdução Genética , Proteína rhoA de Ligação ao GTP/metabolismo
14.
BMC Geriatr ; 20(1): 149, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321436

RESUMO

BACKGROUND: This study explored the effects of physical activity and sedentary behaviour on the decline of cognitive ability among the elderly. To compensate for the limitations of self-reported physical activity, objective measures were used. METHODS: A cross-sectional survey of 308 aged people mean 68.66 ± 5.377 years, in Nanjing, China, was conducted. Physical activity was measured using the ActiGraph GT3X+, and cognitive function was measured using the Montreal Cognitive Assessment. RESULTS: The overall participant model, adjusted for age, BMI, education, and monthly average income, found that light physical activity (ß = 0.006, p < 0.01), moderate-vigorous physical activity (ß = 0.068, p < 0.001), and total physical activity (ß = 0.006, p < 0.01) had a significant linear relationship with cognitive ability, while sedentary time did not (ß = - 0.020, p>0.05). Further, light physical activity only affects the cognitive ability of elderly females (ß = 0.006, p < 0.05). There was an inverted 'U' association between moderate-vigorous physical activity and cognitive ability. The association models found that moderate-vigorous physical activity in the 22.13 min·day- 1~38.79 min·day- 1 range affected cognitive ability most beneficially, with the highest beta coefficient among all groups (ß = 0.091, p < 0.05). CONCLUSIONS: While physical activity can significantly improve cognitive ability among the elderly, sedentary behaviour is associated with decreased cognitive function across genders.


Assuntos
Cognição , Exercício Físico , Comportamento Sedentário , Acelerometria , Idoso , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Proc Natl Acad Sci U S A ; 114(20): E3974-E3983, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28465430

RESUMO

Visual information is conveyed from the eye to the brain by distinct types of retinal ganglion cells (RGCs). It is largely unknown how RGCs acquire their defining morphological and physiological features and connect to upstream and downstream synaptic partners. The three Brn3/Pou4f transcription factors (TFs) participate in a combinatorial code for RGC type specification, but their exact molecular roles are still unclear. We use deep sequencing to define (i) transcriptomes of Brn3a- and/or Brn3b-positive RGCs, (ii) Brn3a- and/or Brn3b-dependent RGC transcripts, and (iii) transcriptomes of retinorecipient areas of the brain at developmental stages relevant for axon guidance, dendrite formation, and synaptogenesis. We reveal a combinatorial code of TFs, cell surface molecules, and determinants of neuronal morphology that is differentially expressed in specific RGC populations and selectively regulated by Brn3a and/or Brn3b. This comprehensive molecular code provides a basis for understanding neuronal cell type specification in RGCs.


Assuntos
Encéfalo/metabolismo , Proteínas de Membrana/metabolismo , Células Ganglionares da Retina/metabolismo , Fator de Transcrição Brn-3/metabolismo , Animais , Orientação de Axônios , Encéfalo/embriologia , Comunicação Celular , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Camundongos , Células Ganglionares da Retina/citologia , Transcriptoma
16.
Proc Natl Acad Sci U S A ; 114(10): 2741-2746, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28223508

RESUMO

Intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin and mediate several non-image-forming visual functions, including circadian photoentrainment and the pupillary light reflex (PLR). ipRGCs act as autonomous photoreceptors via the intrinsic melanopsin-based phototransduction pathway and as a relay for rod/cone input via synaptically driven responses. Under low light intensities, where only synaptically driven rod/cone input activates ipRGCs, the duration of the ipRGC response will be determined by the termination kinetics of the rod/cone circuits. Little is known, however, about the termination kinetics of the intrinsic melanopsin-based phototransduction pathway and its contribution to several melanopsin-mediated behaviors. Here, we show that C-terminal phosphorylation of melanopsin determines the recovery kinetics of the intrinsic melanopsin-based photoresponse in ipRGCs, the duration of the PLR, and the speed of reentrainment. In contrast, circadian phase alignment and direct effects of light on activity (masking) are not influenced by C-terminal phosphorylation of melanopsin. Electrophysiological measurements demonstrate that expression of a virally encoded melanopsin lacking all C-terminal phosphorylation sites (C terminus phosphonull) leads to a prolonged intrinsic light response. In addition, mice expressing the C terminus phosphonull in ipRGCs reentrain faster to a delayed light/dark cycle compared with mice expressing virally encoded WT melanopsin; however, the phase angle of entrainment and masking were indistinguishable. Importantly, a sustained PLR in the phosphonull animals is only observed at brighter light intensities that activate melanopsin phototransduction, but not at dimmer light intensities that activate only the rod/cone pathway. Taken together, our results highlight how the kinetics of the melanopsin photoresponse differentially regulate distinct light-mediated behaviors.


Assuntos
Comportamento Animal , Transdução de Sinal Luminoso/genética , Células Ganglionares da Retina/metabolismo , Opsinas de Bastonetes/metabolismo , Animais , Ritmo Circadiano/genética , Cinética , Luz , Transdução de Sinal Luminoso/fisiologia , Camundongos , Técnicas de Patch-Clamp , Fosforilação/genética , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/fisiologia , Reflexo Pupilar/genética , Reflexo Pupilar/fisiologia , Retina/metabolismo , Retina/fisiologia , Células Ganglionares da Retina/fisiologia , Opsinas de Bastonetes/química , Opsinas de Bastonetes/genética , Sinapses/genética , Sinapses/metabolismo , Visão Ocular/genética , Visão Ocular/fisiologia
17.
Angew Chem Int Ed Engl ; 59(33): 13923-13928, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32436324

RESUMO

The applications of the most promising Fe-N-C catalysts are prohibited by their limited intrinsic activities. Manipulating the Fe energy level through anchoring electron-withdrawing ligands is found effective in boosting the catalytic performance. However, such regulation remains elusive as the ligands are only uncontrollably introduced oweing to their energetically unstable nature. Herein, we report a rational manipulation strategy for introducing axial bonded O to the Fe sites, attained through hexa-coordinating Fe with oxygen functional groups in the precursor. Moreover, the O modifier is stabilized by forming the Fe-O-Fe bridge bond, with the approximation of two FeN4 sites. The energy level modulation thus created confers the sites with an intrinsic activity that is over 10 times higher than that of the normal FeN4 site. Our finding opens a novel strategy to manage coordination environments at an atomic level for high activity ORR catalysts.

18.
Angew Chem Int Ed Engl ; 59(32): 13568-13574, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32495981

RESUMO

Synthesis of well-defined atomically mixed alloy nanoparticles on desired substrates is an ultimate goal for their practical application. Herein we report a general approach for preparing atomically mixed AuPt, AuPd, PtPd, AuPtPd NAs(nanoalloys) through single-atom level manipulation. By utilizing the ubiquitous tendency of aggregation of single atoms into nanoparticles at elevated temperatures, we have synthesized nanoalloys on a solid solvent with CeO2 as a carrier and transition-metal single atoms as an intermediate state. The supported nanoalloys/CeO2 with ultra-low noble metal content (containing 0.2 wt % Au and 0.2 wt % Pt) exhibit enhanced catalytic performance towards complete CO oxidation at room temperature and remarkable thermostability. This work provides a general strategy for facile and rapid synthesis of well-defined atomically mixed nanoalloys that can be applied for a range of emerging techniques.

19.
Gene Ther ; 26(9): 386-398, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31308478

RESUMO

Recombinant adeno-associated virus (rAAV) has been widely used for gene delivery in animal models and successfully applied in clinical trials for treating inherited retinal disease. Although subretinal delivery of AAVs can effectively transduce photoreceptors and/or retinal pigmental epithelium (RPE), cells most affected by inherited retinal diseases, the procedure is invasive and complicated, and only delivers the gene to a limited retinal area. AAVs can also be delivered intravitreally to the retina, a much less invasive nonsurgical procedure. However, intravitreal administration of non-modified AAV serotypes tends to transduce only ganglion cells and inner nuclear layer cells. To date, most non-modified AAV serotypes that have been identified are incapable of efficiently transducing photoreceptors and/or RPE when delivered intravitreally. In this study, we investigate the retinal tropism of AAVrh10 vector administered by intravitreal injection to mouse, rat, and rabbit eyes. Our results demonstrate that AAVrh10 is capable of transducing not only inner retinal cells, but also outer retinal cells in all three species, though the transduction efficiency in rabbit was low. In addition, AAVrh10 preferentially transduced outer retinal cells in mouse models of retinal disease. Therefore, AAVrh10 vector could be a useful candidate to intravitreally deliver genes to photoreceptor and RPE cells.


Assuntos
Dependovirus/genética , Retina , Transdução Genética/métodos , Animais , Citomegalovirus/genética , Dependovirus/fisiologia , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Injeções Intravítreas , Masculino , Camundongos , Células Fotorreceptoras/virologia , Coelhos , Ratos , Ratos Sprague-Dawley , Retina/efeitos dos fármacos , Retina/virologia , Doenças Retinianas/terapia , Tropismo Viral
20.
J Am Chem Soc ; 141(50): 19800-19806, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31763837

RESUMO

Emerging as a new frontier in heterogeneous catalysis, single-atom site catalysts (SSCs) have sparked enormous attention and bring about new opportunities to oxygen reduction electrocatalysis. Despite considerable progress achieved recently, most of the reported SSCs suffer from either insufficient activity or unsatisfactory stability, which severely retards their practical application. Here, we demonstrate a novel Ru-SSC with appropriate adsorption free energy of OH* (ΔGOH*) to confer excellent activity and low Fenton reactivity to maintain long-term stability. The as-developed Ru-SSC exhibits encouraging oxygen reduction reaction turnover frequency of 4.99 e- s-1 sites-1, far exceeding the state-of-the-art Fe-SSC counterpart (0.816 e- s-1 sites-1), as a result of Ru energy level regulation via spontaneous OH binding. Furthermore, Ru-SSC exhibits greatly suppressed Fenton reactivity, with restrained generation of reactive oxygen species directly observed, thus endowing the Ru-SSC with much more superior stability (only 17 mV negative shift after 20 000 cycles) than the Fe-SSC counterpart (31 mV). The practical application of Ru-SSC is further validated by its excellent activity and stability in a real fuel cell device.

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