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1.
J Am Chem Soc ; 146(15): 10599-10607, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38567740

RESUMO

The success of electrochemical CO2 reduction at high current densities hinges on precise interfacial transportation and the local concentration of gaseous CO2. However, the creation of efficient CO2 transportation channels remains an unexplored frontier. In this study, we design and synthesize hydrophobic porous Cu2O spheres with varying pore sizes to unveil the nanoporous channel's impact on gas transfer and triple-phase interfaces. The hydrophobic channels not only facilitate rapid CO2 transportation but also trap compressed CO2 bubbles to form abundant and stable triple-phase interfaces, which are crucial for high-current-density electrocatalysis. In CO2 electrolysis, in situ spectroscopy and density functional theory results reveal that atomic edges of concave surfaces promote C-C coupling via an energetically favorable OC-COH pathway, leading to overwhelming CO2-to-C2+ conversion. Leveraging optimal gas transportation and active site exposure, the hydrophobic porous Cu2O with a 240 nm pore size (P-Cu2O-240) stands out among all the samples and exhibits the best CO2-to-C2+ productivity with remarkable Faradaic efficiency and formation rate up to 75.3 ± 3.1% and 2518.2 ± 8.1 µmol h-1 cm-2, respectively. This study introduces a novel paradigm for efficient electrocatalysts that concurrently addresses active site design and gas-transfer challenges.

2.
EMBO J ; 43(8): 1499-1518, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38528181

RESUMO

The intestinal pathogen Salmonella enterica rapidly enters the bloodstream after the invasion of intestinal epithelial cells, but how Salmonella breaks through the gut-vascular barrier is largely unknown. Here, we report that Salmonella enters the bloodstream through intestinal CX3CR1+ macrophages during early infection. Mechanistically, Salmonella induces the migration/invasion properties of macrophages in a manner dependent on host cell actin and on the pathogen effector SteC. SteC recruits host myosin light chain protein Myl12a and phosphorylates its Ser19 and Thr20 residues. Myl12a phosphorylation results in actin rearrangement, and enhanced migration and invasion of macrophages. SteC is able to utilize a wide range of NTPs other than ATP to phosphorylate Myl12a. We further solved the crystal structure of SteC, which suggests an atypical dimerization-mediated catalytic mechanism. Finally, in vivo data show that SteC-mediated cytoskeleton manipulation is crucial for Salmonella breaching the gut vascular barrier and spreading to target organs.


Assuntos
Cadeias Leves de Miosina , Salmonella enterica , Cadeias Leves de Miosina/genética , Cadeias Leves de Miosina/metabolismo , Actinas/metabolismo , Células Epiteliais/metabolismo , Macrófagos/metabolismo
3.
J Xray Sci Technol ; 31(4): 745-756, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37092211

RESUMO

OBJECTIVE: The aim of this study is to investigate the radiation dose and image quality of head CT using SPS and OBTCM techniques. METHODS: Three anthropomorphic head phantoms (1-yr-old, 5-yr-old, and adult) were used. Images were acquired using four modes (Default protocol, OBTCM, SPS, and SPS+OBTCM). Absorbed dose to the lens, anterior brain (brain_A), and posterior brain (brain_P) was measured and compared. Image noise and CNR were assessed in the selected regions of interest (ROIs). RESULTS: Compared with that in the Default protocol, the absorbed dose to the lens reduced by up to 28.33%,71.38%, and 71.12% in OBTCM, SPS, and SPS+OBTCM, respectively. The noise level in OBTCM slightly (≤1.45HU) increased than that in Default protocol, and the SPS or SPS+OBTCM mode resulted in a quantitatively small increase (≤2.58HU) in three phantoms. There was no significant difference in CNR of different phantoms under varies scanning modes (p > 0.05). CONCLUSIONS: During head CT examinations, the SPS mode can reduce the radiation dose while maintaining image quality. SPS+OBTCM couldn't further effectively reduce the absorbed dose to the lens for 1-yr and 5-yr-old phantoms. Thus, SPS mode in pediatric and SPS+OBTCM mode in adult are better than other modes, and should be used in clinical practice.


Assuntos
Redução da Medicação , Proteção Radiológica , Adulto , Humanos , Criança , Doses de Radiação , Proteção Radiológica/métodos , Cabeça/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imagens de Fantasmas
4.
Front Cardiovasc Med ; 9: 1036780, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36465434

RESUMO

Background and objective: Coronary artery bypass grafting (CABG) is the reference standard intervention in coronary artery disease (CAD) patients with three-vessel disease (3VD). We aimed to evaluate the predictive value of left ventricular (LV) dyssynchrony for short-term adverse outcomes in patients with 3VD undergoing CABG with preserved or mildly reduced LV ejection fraction (LVEF). Materials and methods: This study involved ninety-five 3VD patients with preserved or mildly reduced LVEF undergoing scheduled on-pump CABG. The pre-operative diameters and volumes of LV and LVEF were obtained by two-dimensional echocardiography. LV dyssynchrony parameters were acquired by real-time three-dimensional echocardiography (RT-3DE) and analyzed by HeartModel quantification software. And the perfusion index of LV was obtained by contrast echocardiography. The clinical endpoints of short-term adverse outcomes comprised 30-day mortality and/or composite outcomes of postoperative complications. Univariate and multivariate logistic regression analyses were used to identify risk factors for the occurrence of post-CABG short-term adverse outcomes. Results: Short-term adverse outcomes occurred in 12 (12.6%) patients. These patients had higher LV dyssynchrony parameters obtained through RT-3DE. The standard deviation (SD) of the time to minimum systolic volume (Tmsv) corrected by heart rate over 16 segments (Tmsv16-SD%) [odds ratio (OR), 1.362; 95% confidence interval (CI) (1.090-1.702); P = 0.006], one of the LV dyssynchrony parameters, was independently associated with short-term adverse outcomes. Patients with poor synchronization tended to spend more time in the intensive care unit (ICU) and hospital after surgery. Conclusion: Pre-operative LV dyssynchrony parameter Tmsv16-SD% obtained through RT-3DE could be a useful additional predictor of postoperative short-term adverse outcomes in 3VD patients with preserved or mildly reduced LVEF undergoing CABG.

5.
Int J Hypertens ; 2022: 1447425, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248198

RESUMO

Objective: The aim of this study was to investigate the changes of syndecan-4 (SDC-4) during the hypertensive period in two kidney-two clip (2K2C) hypertension rats and compare them to brain natriuretic peptide (BNP) and the echocardiographic parameters for diastolic function evaluation in the rat model of 2K2C hypertension. Methods: A total of 36 Sprague-Dawley (SD) rats were used in this study. Hypertension was induced in 21 by 2K2C surgery, and 15 were sham-operated. Both the 2K2C hypertension group (n = 21) and the sham-operated group (n = 15) were equally divided into 3 subgroups according to the schedules (week 4, week 8, and week 12). Serum SDC-4 and BNP were detected by ELISA, and echocardiography indexes were acquired. Results: The level of SDC-4 and cardiac fibrosis increased gradually as the experiment was processed, and BNP, Tei index, and E/E' followed to be raised as high blood pressure was maintained after four weeks in the 2K2C hypertension rats. In the earlier 4 weeks, only SDC-4 and cardiac fibrosis were significantly increased in 2K2C hypertensive rats in comparison with normotensive rats. And it was shown that SDC-4 was positively correlated with BNP level during the entire study (r = 0.762, p < 0.01). Conclusion: SDC-4 increases gradually during the process of diastolic dysfunction in 2K2C hypertensive rats. SDC-4 is the earliest biomarker reflecting diastolic dysfunction in this model, superior to E/E' and the Tei index. Our results indicate that serum SDC-4 could act as an early biomarker to show diastolic dysfunction.

6.
Front Neurosci ; 16: 947282, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090281

RESUMO

Objective: To validate the clinical reliability of an individualized CT image-guided' free-hand catheter technique (CTGFC) for basal ganglia hematoma (BGH) evacuation. Methods: From January 2017 to December 2020, 58 cases of patients with BGH who underwent catheter evacuation were enrolled. The surgery was conducted using the CTGFC (n = 31) or stereotactic catheter technique (STC, n = 27). The authors evaluated the baseline characteristics, operation-related indicators, postoperative complications, hospitalization-related indicators, short-term and long-term functional outcomes, and mortality rate 1 year after surgery. Results: All patients underwent BGH evacuation under non-general anesthesia in the CTGFC group. The operative time (p < 0.01) and operation costs (p < 0.05) were significantly shorter in the CTGFC group than that in the STC group (p < 0.01). Comparable results were found in the catheter indwelling duration, residual hematoma volume, hematoma evacuation rate, incidence of postoperative complications, hospital ICU stay, and hospital costs between these two groups (p > 0.05). The duration of hospital stay was remarkably shorter in the CTGFC group than that in the STC group (p < 0.01). There were no differences in terms of the short-time functional outcomes score at discharge, including the Glasgow outcome scale (GOS) score, the activities of daily living (ADL) score, and the Karnofsky performance score (KPS). Moreover, comparable findings were also found in the 1-year postoperative GOS score, ADL score, KPS score, and mortality rate between these two groups. Conclusion: The simple CTGFC-assisted surgery was a safe and reliable option for BGH evacuation, especially in primary medical institutes and emergency situations with limited medical resources.

7.
mBio ; 13(3): e0020722, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35532216

RESUMO

Iron limitation is a universal strategy of host immunity during bacterial infection. However, the mechanisms by which pathogens antagonize host nutritional immunity have not been fully elucidated. Here, we identified a requirement for the UMPylator YdiU for this process in Salmonella. The expression of YdiU was dramatically induced by the metal starvation signal. The intracellular iron content was much lower in the ΔydiU strain than in wild-type Salmonella, and the ΔydiU strain exhibited severe growth defect under metal deficiency environments. Genome-wide expression analyses revealed significantly decreased expression of iron uptake genes in ΔydiU strain compared with the wild-type strain. Interestingly, YdiU did not affect the expression level of the major iron uptake regulator Fur but directly UMPylated Fur on its H118 residue in vivo and in vitro. UMPylation destroyed the Fur dimer, promoted Fur aggregation, and eliminated the DNA-binding activity of Fur, thus abolishing the ability of Fur to inhibit iron uptake. Restricting Fur to the deUMPylated state dramatically eliminates Salmonella iron uptake in iron deficiency environments. In parallel, YdiU facilitates Salmonella survival within host cells by regulating the iron uptake pathway. IMPORTANCE Salmonella is the major pathogen causing bacterial enteric illness in both humans and animals. Iron availability is strictly controlled upon Salmonella entry into host cells. The mechanisms by which Salmonella balances the acquisition of sufficient iron while preventing a toxic overload has not been fully understood. Here, we reveal a novel regulation process of iron acquisition mediated by the UMPylator YdiU. Fur acts as the central regulator of bacterial iron homeostasis. YdiU UMPylates Fur on H118 and prevents Fur from binding to target DNA, thus activating the expression of iron uptake genes under iron-deficient conditions. We describe the first posttranslational modification-based regulation of Fur and highlight a potential mechanism by which Salmonella can adapt to eliminate host nutritional immunity.


Assuntos
Deficiências de Ferro , Proteínas Repressoras , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Ferro/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Salmonella/genética , Salmonella/metabolismo
8.
Cell Rep ; 32(12): 108161, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32966796

RESUMO

Sensing stressful conditions and adjusting the cellular metabolism to adapt to the environment are essential activities for bacteria to survive in variable situations. Here, we describe a stress-related protein, YdiU, and characterize YdiU as an enzyme that catalyzes the covalent attachment of uridine-5'-monophosphate to a protein tyrosine/histidine residue, an unusual modification defined as UMPylation. Mn2+ serves as an essential co-factor for YdiU-mediated UMPylation. UTP and Mn2+ binding converts YdiU to an aggregate-prone state facilitating the recruitment of chaperones. The UMPylation of chaperones prevents them from binding co-factors or clients, thereby impairing their function. Consistent with the recent finding that YdiU acts as an AMPylator, we further demonstrate that the self-AMPylation of YdiU padlocks its chaperone-UMPylation activity. A detailed mechanism is proposed based on the crystal structures of Apo-YdiU and YdiU-AMPNPP-Mn2+ and on molecular dynamics simulation models of YdiU-UTP-Mn2+ and YdiU-UTP-peptide. In vivo data demonstrate that YdiU effectively protects Salmonella from stress-induced ATP depletion through UMPylation.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Manganês/metabolismo , Transdução de Sinais , Estresse Fisiológico , Uridina Monofosfato/metabolismo , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Biocatálise , Modelos Moleculares , Chaperonas Moleculares/metabolismo , Agregados Proteicos , Domínios Proteicos , Salmonella typhimurium/metabolismo , Salmonella typhimurium/ultraestrutura , Relação Estrutura-Atividade , Especificidade por Substrato , Uridina Trifosfato/metabolismo
9.
Echocardiography ; 36(10): 1944-1946, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31654441

RESUMO

Primary cardiac neoplasms are rare, and the pericardial schwannoma has an even lower occurrence. We report a case of pericardial schwannoma in China, which is the eighth reported case adding to the existing literature on pericardial schwannoma, and this is the first case reported complicated with massive pericardial effusion. Pericardial schwannomas are usually benign, but they can sometimes have a malignant tendency and cause life-threatening complications. Thus, it should be managed aggressively and completely resected.


Assuntos
Ecocardiografia/métodos , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/diagnóstico por imagem , Neurilemoma/complicações , Neurilemoma/diagnóstico por imagem , Derrame Pericárdico/complicações , Derrame Pericárdico/diagnóstico por imagem , Adulto , China , Neoplasias Cardíacas/cirurgia , Humanos , Masculino , Neurilemoma/cirurgia , Derrame Pericárdico/cirurgia , Pericárdio/diagnóstico por imagem , Pericárdio/cirurgia , Tomografia Computadorizada por Raios X/métodos
10.
Mol Genet Metab Rep ; 21: 100513, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31534909

RESUMO

GM1 gangliosidosis is an autosomal recessive neurodegenerative disorder caused by the deficiency of lysosomal ß-galactosidase (ß-gal) and resulting in accumulation of GM1 ganglioside. The disease spectrum ranges from infantile to late onset and is uniformly fatal, with no effective therapy currently available. Although animal models have been useful for understanding disease pathogenesis and exploring therapeutic targets, no relevant human central nervous system (CNS) model system has been available to study its early pathogenic events or test therapies. To develop a model of human GM1 gangliosidosis in the CNS, we employed CRISPR/Cas9 genome editing to target GLB1 exons 2 and 6, common sites for mutations in patients, to create isogenic induced pluripotent stem (iPS) cell lines with lysosomal ß-gal deficiency. We screened for clones with <5% of parental cell line ß-gal enzyme activity and confirmed GLB1 knockout clones using DNA sequencing. We then generated GLB1 knockout cerebral organoids from one of these GLB1 knockout iPS cell clones. Analysis of GLB1 knockout organoids in culture revealed progressive accumulation of GM1 ganglioside. GLB1 knockout organoids microinjected with AAV9-GLB1 vector showed a significant increase in ß-gal activity and a significant reduction in GM1 ganglioside content compared with AAV9-GFP-injected organoids, demonstrating the efficacy of an AAV9 gene therapy-based approach in GM1 gangliosidosis. This proof-of-concept in a human cerebral organoid model completes the pre-clinical studies to advance to clinical trials using the AAV9-GLB1 vector.

11.
J Clin Res Pediatr Endocrinol ; 11(4): 400-409, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31208162

RESUMO

Objective: To explore the clinical presentation and molecular genetic characteristics of a cohort of congenital hyperinsulinism (CHI) patients from southern China and also to explore the most appropriate therapeutic approaches. Methods: We retrospectively reviewed a cohort of 65 children with CHI. Mutational analysis was performed for KCNJ11 and ABCC8 genes. The GLUD1 gene was sequenced in patients with hyperammonaemia. GCK gene sequencing was performed in those patients with no mutation identified in the ABCC8, KCNJ11 or GLUD1 genes. Results: ABCC8 mutations were identified in 16 (25%) of the cohort, GLUD1 mutations were identified in five children, and no KCNJ11 or GCK mutations were identified. Moreover, some unique features of ABCC8 gene mutations in southern Chinese CHI patients were found in this study. The most common mutation was a deletion/insertion mutation p.Thr1042GlnfsX75 was found in five unrelated patients, which possibly represents a relatively common mutation in southern China. Five novel ABCC8 mutations were detected. The mutations were p.Phe5SerfsX72, p.Gln273ArgfsX85, p.Leu724del, p.Asp1447Gly and IVS 25-1G>T. Five compound heterozygous mutations of ABCC8 gene were identified in this study, and three of these patients were diazoxide-responsive. Forty patients were diazoxide-responsive, 13 patients were diazoxide-unresponsive and 12 patients received dietary treatment only. A pancreatectomy was performed in 10 patients who were unresponsive to medical treatment. Conclusion: To the best of our knowledge, this is the first study of CHI in south China. Mutations in ABCC8 are the most common causes of CHI in this cohort. Diazoxide and dietary treatment were effective in most patients. Multicentre studies are necessary to obtain the long-term follow-up characteristics of such patients at a national level.


Assuntos
Glicemia/efeitos dos fármacos , Hiperinsulinismo Congênito/genética , Hiperinsulinismo Congênito/terapia , Análise Mutacional de DNA , Diazóxido/uso terapêutico , Carboidratos da Dieta/administração & dosagem , Glutamato Desidrogenase/genética , Mutação , Pancreatectomia , Receptores de Sulfonilureias/genética , Biomarcadores/sangue , Glicemia/genética , Glicemia/metabolismo , Criança , Pré-Escolar , China , Hiperinsulinismo Congênito/sangue , Hiperinsulinismo Congênito/diagnóstico , Estudos Transversais , Diazóxido/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Lactente , Recém-Nascido , Masculino , Pancreatectomia/efeitos adversos , Fenótipo , Valor Preditivo dos Testes , Estudos Retrospectivos , Resultado do Tratamento
12.
BMC Cardiovasc Disord ; 19(1): 9, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30621585

RESUMO

BACKGROUND: Takotsubo cardiomyopathy (TCM) is a brief ventricular dysfunction that usually occurs after emotional or physical stress. Here, we report a patient who underwent cardiac surgery and then developed TCM during the postoperative period. CASE PRESENTATION: A 51-year-old woman was admitted to our hospital complaining of chest tightness, palpitations and dyspnoea after activity. An echocardiogram performed by our hospital showed rheumatic heart disease (severe mitral stenosis and regurgitation) with normal cardiac function and wall motion. After mitral valve replacement, this patient developed heart failure with low blood pressure and tachycardia. Urgent bedside echocardiography demonstrated akinesis in the middle and apical segments of the left ventricle and a depressed ejection fraction (EF) of 36%. Myocardial contrast echocardiography (MCE) showed similar enhancement intensity in the basal, middle and apical segments. Quantitative analysis showed approximately equivalent maximum intensity in these regions. The diagnosis was considered TCM instead of myocardial infarction. Then, an intra-aortic balloon pump was inserted to maintain effective circulation and reduce the postcardiac load. Given ventilation therapy, postoperative anticoagulation therapy and anti-infection treatment, the patient recovered quickly. In the follow-up examination, the patient remained asymptomatic and showed normalization of ventricular wall motion in the apical segment. CONCLUSION: This report presents a case of TCM in which MCE was used to demonstrate intact microvascular perfusion despite apical akinesis. This report might support the use of MCE as a substitute for invasive coronary angiography.


Assuntos
Meios de Contraste/administração & dosagem , Ecocardiografia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Insuficiência da Valva Mitral/cirurgia , Estenose da Valva Mitral/cirurgia , Fosfolipídeos/administração & dosagem , Cardiopatia Reumática/cirurgia , Hexafluoreto de Enxofre/administração & dosagem , Cardiomiopatia de Takotsubo/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/fisiopatologia , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/fisiopatologia , Valor Preditivo dos Testes , Cardiopatia Reumática/diagnóstico por imagem , Cardiopatia Reumática/fisiopatologia , Cardiomiopatia de Takotsubo/etiologia , Cardiomiopatia de Takotsubo/fisiopatologia , Cardiomiopatia de Takotsubo/terapia , Resultado do Tratamento , Função Ventricular Esquerda
13.
Chem Commun (Camb) ; 54(73): 10347-10350, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30151527

RESUMO

Stable mesoporous nickel (Ni) films can be prepared using polystyrene-b-poly-(oxyethylene) (PS-b-PEO) micelles as sacrificial templates. In this method, positively charged Ni precursors form hydrogen bonds with the PEO segments of the micelles, which are then co-electrodeposited on the surface of a working electrode. Changing the applied voltage during electrodeposition modifies the deposition rate and ultimately controls the architecture of the mesoporous Ni film.

14.
Plant Cell Environ ; 41(10): 2449-2462, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29869796

RESUMO

Cadmium (Cd) stress is one of the most serious heavy metal stresses limiting plant growth and development. However, the molecular mechanisms underlying Cd-induced root growth inhibition remain unclear. Here, we found that ethylene signalling positively regulates Cd-induced root growth inhibition. Arabidopsis seedlings pretreated with the ethylene precursor 1-aminocyclopropane-1-carboxylic acid exhibited enhanced Cd-induced root growth inhibition, whereas the addition of the ethylene biosynthesis inhibitor aminoethoxyvinyl glycine decreased Cd-induced root growth inhibition. Consistently, ethylene-insensitive mutants, such as ein4-1, ein3-1 eil1-1 double mutant, and EBF1ox, displayed an increased tolerance to Cd. Furthermore, we also observed that Cd inhibited EIN3 protein degradation, a process that was regulated by ethylene signalling. Genetic and biochemical analyses showed that EIN3 enhanced root growth inhibition under Cd stress through direct binding to the promoters and regulating the expression of XTH33 and LSU1, which encode key regulators of cell wall extension and sulfur metabolic process, respectively. Collectively, our study demonstrates that ethylene plays a positive role in Cd-regulated root growth inhibition through EIN3-mediated transcriptional regulation of XTH33 and LSU1 and provides a molecular framework for the integration of environmental signals and intrinsic regulators in modulating plant root growth.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/crescimento & desenvolvimento , Cádmio/farmacologia , Etilenos/metabolismo , Glicosiltransferases/fisiologia , Proteínas Nucleares/fisiologia , Reguladores de Crescimento de Plantas/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Fatores de Transcrição/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA , Ensaio de Desvio de Mobilidade Eletroforética , Regulação da Expressão Gênica de Plantas , Glicosiltransferases/metabolismo , Microscopia Confocal , Proteínas Nucleares/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição/metabolismo , Técnicas do Sistema de Duplo-Híbrido
15.
Plant Physiol ; 177(2): 819-832, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29720555

RESUMO

Auxin has been shown to enhance root growth inhibition under aluminum (Al) stress in Arabidopsis (Arabidopsis thaliana). However, in maize (Zea mays), auxin may play a negative role in the Al-induced inhibition of root growth. In this study, we identified mutants deficient in the maize auxin efflux carrier P-glycoprotein (ZmPGP1) after ethyl methanesulfonate mutagenesis and used them to elucidate the contribution of ZmPGP1 to Al-induced root growth inhibition. Root growth in the zmpgp1 mutant, which forms shortened roots and is hyposensitive to auxin, was less inhibited by Al stress than that in the inbred line B73. In the zmpgp1 mutants, the root tips displayed higher auxin accumulation and enhanced auxin signaling under Al stress, which was also consistent with the increased expression of auxin-responsive genes. Based on the behavior of the auxin-responsive marker transgene, DR5rev:RFP, we concluded that Al stress reduced the level of auxin in the root tip, which contrasts with the tendency of Al stress-induced Arabidopsis plants to accumulate more auxin in their root tips. In addition, Al stress induced the expression of ZmPGP1 Therefore, in maize, Al stress is associated with reduced auxin accumulation in root tips, a process that is regulated by ZmPGP1 and thus causes inhibition of root growth. This study provides further evidence about the role of auxin and auxin polar transport in Al-induced root growth regulation in maize.


Assuntos
Alumínio/toxicidade , Ácidos Indolacéticos/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Zea mays/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Meristema/efeitos dos fármacos , Meristema/genética , Meristema/metabolismo , Mutação , Ácidos Naftalenoacéticos/farmacologia , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transdução de Sinais , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
16.
Int J Biol Sci ; 14(5): 542-548, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29805305

RESUMO

Smad ubiquitin regulatory factor 2 (Smurf2) is a HECT domain-containing E3 ubiquitin ligase. Together with its closely related homolog Smurf1, Smurf2 was initially recognized as a negative regulator of transforming growth factor-ß (TGF-ß) and bone morphogenetic protein (BMP) signaling, but subsequent studies have expanded its function to regulate many different signaling pathways and play important roles in genomic stability, cell polarity, tissue homeostasis and carcinogenesis. Mice with conventional knockout of Smurf1 or Smurf2 alleles are viable, but conventional Smurf1 and Smurf2 double knockout mice were early embryonic lethal. In order to study the physiological function of Smurfs during late stage of embryonic development or in adult animals, we generated Smurf2flox/flox mice carrying a targeted mutation for conditional Smurf2 gene inactivation. We demonstrated that Cre-mediated recombination using Alb-Cre, a Cre line expressed in hepatocyte, results in specific deletion of the gene in liver tissue. We also showed that Cre-mediated recombination in mouse embryonic fibroblasts (MEFs) with Smurf2flox/flox genotype resulted in generation of Smurf2 knockout MEFs, and Smurf2 deficiency affects multiple signaling pathways. Therefore, this animal model will be useful to study the distinct roles of Smurf2 in different tissues at different ages.


Assuntos
Recombinação Genética , Ubiquitina-Proteína Ligases/genética , Alelos , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Feminino , Fibroblastos/metabolismo , Genótipo , Heterozigoto , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Genéticos , Transdução de Sinais , Distribuição Tecidual , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina-Proteína Ligases/fisiologia
17.
Am J Reprod Immunol ; 79(6): e12843, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29516577

RESUMO

PROBLEM: Prokineticin 2 (PK2), a pro-inflammatory peptide, is highly expressed in primary spermatocytes. However, systematic research on PK2 and testicular inflammation is lacking to date. METHOD OF STUDY: An experimental autoimmune orchitis (EAO) model was established to detect the expression of PK2 and its receptor (prokineticin receptor 1, PKR1) 50 and 80 days after immunization. PK2 siRNA sequence was injected into the rat rete testis to downregulate the expression of PK2. PK2 was over-expressed in the testis by injecting PK2 protein through the rat rete testis at different concentrations. Testicular morphology and expression of inducible nitric oxide synthase (iNOS) were detected after the intervention. RESULTS: Results showed that PK2 and PKR1 were upregulated in EAO at 50 days and downregulated at 80 days. PK2 over-expression contributed to the apoptosis of spermatogenic epithelial cells and increased infiltration of the inflammatory cells, whereas PK2 under-expression showed no change. Furthermore, iNOS expression was increased significantly when PK2 was over-expressed. CONCLUSION: This finding demonstrated that the PK2/PKR1 signals may have an essential role in the regulation of testicular inflammation through iNOS. PK2 interference may represent a novel and promising therapeutic strategy for the clinical management of orchitis.


Assuntos
Doenças Autoimunes/metabolismo , Hormônios Gastrointestinais/metabolismo , Inflamação/metabolismo , Neuropeptídeos/metabolismo , Orquite/metabolismo , Testículo/metabolismo , Animais , Apoptose/fisiologia , Modelos Animais de Doenças , Regulação para Baixo/fisiologia , Células Epiteliais , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/metabolismo , Espermatócitos/metabolismo , Regulação para Cima/fisiologia
18.
Endocr Pract ; 23(12): 1379-1386, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29019716

RESUMO

OBJECTIVE: Hyperprolactinemia has been associated with endothelial dysfunction and a wide range of cardiovascular risk factors, thus it can potentially lead to cardiac dysfunction. The present study was designed to interrogate our hypothesis that hyperprolactinemia can contribute to preclinical impaired left ventricular function. METHODS: Thirty-one prolactinoma patients and 60 healthy volunteers were prospectively recruited. Left ventricular function was evaluated using conventional two dimensions and M-mode echocardiography, as well as Doppler tissue imaging (DTI). RESULTS: The Tei index (0.45 ± 0.06 vs. 0.41 ± 0.03, P = .005) and ratio of transmitral and myocardial early diastolic velocities (E/Em; 6.30 ± 1.45 vs. 5.64 ± 0.69, P = .045) were significantly higher, and septal systolic velocity (Sm; 9.88 ± 1.45 vs. 11.58 ± 1.28 cm/s, P<.001) was significantly lower in prolactinoma patients. Furthermore, significant motional abnormalities were detected in regional segments of prolactinoma patients. Pearson's correlation analysis revealed that prolactin level was inversely associated with Sm (r = -0.373, P = .009) and late diastolic phase (Am; r = -0.293, P = .043). Moreover, inverse correlations between prolactin and partial left ventricular segment wall motion were found, including the basal (r = -0.363, P = .014), middle (r = -0.418, P = .004), and apical segment (r = -0.574, P<.001) of the posterior ventricular septum. Multivariate linear regression analysis revealed that prolactin (ß = -0.28, 95% confidence interval -0.011 to 0, P = .035), as a single factor, can significantly predict decreased Sm, independent of traditional vascular risk factors. CONCLUSION: Our results suggest that subclinical cardiac dysfunction occurs in untreated prolactinoma patients and is characterized by impaired systolic and diastolic function of the left ventricle, as well as regional segment motional abnormality. ABBREVIATIONS: A = transmitral late diastolic velocity Am = late diastolic phase Apo = apolipoprotein DTI = Doppler tissue imaging E = transmitral early diastolic velocity Em = myocardial early diastolic velocity FMD = flow-mediated dilation HOMA-IR = homeostasis model assessment of insulin resistance hsCRP = high-sensitivity C-reactive protein IMT = intima media thickness LDL-C = low-density lipoprotein cholesterol LV = left ventricular PPCM = postpartum cardiomyopathy Sm = septal systolic velocity.


Assuntos
Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/fisiopatologia , Prolactinoma/complicações , Prolactinoma/fisiopatologia , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Assintomáticas , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Ecocardiografia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/diagnóstico , Prolactinoma/diagnóstico , Fatores de Risco , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia
19.
Nanoscale ; 9(36): 13829, 2017 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-28895969

RESUMO

Correction for 'Gold-loaded nanoporous iron oxide nanocubes: a novel dispersible capture agent for tumor-associated autoantibody analysis in serum' by Sharda Yadav et al., Nanoscale, 2017, 9, 8805-8814.

20.
Nanoscale ; 9(25): 8805-8814, 2017 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-28627551

RESUMO

Autoantibodies are produced against tumor associated antigens (TAAs) long before the appearance of any symptoms and thus can serve as promising, non-invasive biomarkers for early diagnosis of cancer. Current conventional methods for autoantibody detection are highly invasive and mostly provide diagnosis in the later stages of cancer. Herein we report a new electrochemical method for early detection of p53 autoantibodies against colon cancer using a strategy that combines the strength of gold-loaded nanoporous iron oxide nanocube (Au@NPFe2O3NC)-based capture and purification while incorporating the inherent simplicity, inexpensive, and portable nature of the electrochemical and naked-eye colorimetric readouts. After the functionalisation of Au@NPFe2O3NC with p53 antigens, our method utilises a two-step strategy that involves (i) magnetic capture and isolation of autoantibodies using p53/Au@NPFe2O3NC as 'dispersible nanocapture agents' in serum samples and (ii) subsequent detection of autoantibodies through a peroxidase-catalyzed reaction on a commercially available disposable screen-printed electrode or naked-eye detection in an Eppendorf tube. This method has demonstrated a good sensitivity (LOD = 0.02 U mL-1) and reproducibility (relative standard deviation, %RSD = <5%, for n = 3) for detecting p53 autoantibodies in serum and has also been successfully applied to analyse a small cohort of clinical samples obtained from colorectal cancer. We believe that the highly inexpensive, rapid, sensitive, and specific nature of our assay could potentially aid in the development of an early diagnostic tool for cancer and related diseases.


Assuntos
Autoanticorpos/sangue , Biomarcadores Tumorais/sangue , Compostos Férricos , Ouro , Nanopartículas Metálicas , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nanoporos , Reprodutibilidade dos Testes , Proteína Supressora de Tumor p53/imunologia
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