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1.
Neurol Sci ; 45(5): 2149-2163, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37994964

RESUMO

OBJECTIVE: Subarachnoid hemorrhage (SAH) is associated with high rates of mortality and permanent disability. At present, there are few definite clinical tools to predict prognosis in SAH patients. The current study aims to develop and assess a predictive nomogram model for estimating the 28-day mortality risk in both non-traumatic or post-traumatic SAH patients. METHODS: The MIMIC-III database was searched to select patients with SAH based on ICD-9 codes. Patients were separated into non-traumatic and post-traumatic SAH groups. Using LASSO regression analysis, we identified independent risk factors associated with 28-day mortality and incorporated them into nomogram models. The performance of each nomogram was assessed by calculating various metrics, including the area under the curve (AUC), net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis (DCA). RESULTS: The study included 999 patients with SAH, with 631 in the non-traumatic group and 368 in the post-traumatic group. Logistic regression analysis revealed critical independent risk factors for 28-day mortality in non-traumatic SAH patients, including gender, age, glucose, platelet, sodium, BUN, WBC, PTT, urine output, SpO2, and heart rate and age, glucose, PTT, urine output, and body temperature for post-traumatic SAH patients. The prognostic nomograms outperformed the commonly used SAPSII and APSIII systems, as evidenced by superior AUC, NRI, IDI, and DCA results. CONCLUSION: The study identified independent risk factors associated with the 28-day mortality risk and developed predictive nomogram models for both non-traumatic and post-traumatic SAH patients. The nomogram holds promise in guiding prognosis improvement strategies for patients with SAH.


Assuntos
Hemorragia Subaracnoídea Traumática , Hemorragia Subaracnóidea , Humanos , Nomogramas , Hemorragia Subaracnóidea/complicações , Área Sob a Curva , Glucose , Prognóstico , Estudos Retrospectivos
2.
J Food Sci Technol ; 61(3): 563-572, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38327855

RESUMO

Pathogenic bacteria contaminations and related diseases in food industries is an urgent issue to solve. The present study aimed to explore natural food biopreservatives from microorganisms. Using dilution-plate method, a strain BBW1542 with antimicrobial activities against various foodborne pathogenic bacteria was isolated from the seabed silt of Beibu Gulf, which was identified as Bacillus subtilis by the morphological observation and 16S rDNA sequences. The antimicrobial substances of B. subtilis BBW1542 exhibited an excellent stability under cool/heat treatment, UV irradiation, acid/alkali treatment, and protease hydrolysis. The genome sequencing analysis and antiSMASH prediction indicated that B. subtilis BBW1542 contained the gene cluster encoding lipopeptides and bacteriocin subtilosin A. MALDI-TOF-MS analysis showed that the lipopeptides from B. subtilis BBW1542 contained C14 and C15 surfactin homologues, together with fengycin homologues of C18 fengycin A/C16 fengycin B and C19 fengycin A/C17 fengycin B. In silico analysis showed that an eight-gene (sboA-albABCDEFG) operon was involved in the biosynthesis of subtilosin A in B. subtilis BBW1542, and the encoded subtilosin A presented an evident closed-loop structure containing 35 amino acids with a molecular weight of 3425.94 Da. Overall, the antagonistic B. subtilis BBW1542 displayed significant resource value and offered a promising alternative in development of food biopreservation. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05864-3.

3.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 49(1): 135-144, 2024 Jan 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38615175

RESUMO

Advance care planning (ACP) is designed to ensure that patients lacking autonomous decision-making capacity receive medical services in accordance with their expectations and preferences. Individuals with advanced cancer are a crucial target for ACP implementation. However, the current practice of ACP in this group in China is suboptimal, demanding high-quality implementation evidence to strengthen ACP in the clinical practice of patients with advanced cancer. The existing literature can be summarized into 27 pieces of evidence across 7 dimensions, including initiation time, intervention content, intervention providers, intervention modalities, communication skills, outcome indicators, and environmental support. The aforementioned evidence could provide crucial support for improving ACP implementation for patients with advanced cancer. Subsequent research efforts should integrate patient preferences and explore the most suitable implementation strategies for ACP in the Chinese population with advanced cancer, considering diverse aspects such as traditional culture, ACP education and training, legislative support, and healthcare system refinement.


Assuntos
Planejamento Antecipado de Cuidados , Neoplasias , Humanos , Povo Asiático , China , Cognição , Neoplasias/terapia
4.
J Biol Chem ; 298(9): 102292, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35868557

RESUMO

Katanin p60 ATPase-containing subunit A1 (KATNA1) is a microtubule-cleaving enzyme that regulates the development of neural protrusions through cytoskeletal rearrangements. However, the mechanism underlying the linkage of the small ubiquitin-like modifier (SUMO) protein to KATNA1 and how this modification regulates the development of neural protrusions is unclear. Here we discovered, using mass spectrometry analysis, that SUMO-conjugating enzyme UBC9, an enzyme necessary for the SUMOylation process, was present in the KATNA1 interactome. Moreover, GST-pull down and co-immunoprecipitation assays confirmed that KATNA1 and SUMO interact. We further demonstrated using immunofluorescence experiments that KATNA1 and the SUMO2 isoform colocalized in hippocampal neurites. We also performed a bioinformatics analysis of KATNA1 protein sequences to identify three potentially conserved SUMOylation sites (K77, K157, and K330) among vertebrates. Mutation of K330, but not K77 or K157, abolished KATNA1-induced microtubule severing and decreased the level of binding observed for KATNA1 and SUMO2. Cotransfection of SUMO2 and wildtype KATNA1 in COS7 cells increased microtubule severing, whereas no effect was observed after cotransfection with the K330R KATNA1 mutant. Furthermore, in cultured hippocampal neurons, overexpression of wildtype KATNA1 significantly promoted neurite outgrowth, whereas the K330R mutant eliminated this effect. Taken together, our results demonstrate that the K330 site in KATNA1 is modified by SUMOylation and SUMOylation of KATNA1 promotes microtubule dynamics and hippocampal neurite outgrowth.


Assuntos
Katanina , Microtúbulos , Crescimento Neuronal , Sumoilação , Adenosina Trifosfatases/metabolismo , Animais , Células COS , Chlorocebus aethiops , Células HEK293 , Humanos , Katanina/genética , Katanina/metabolismo , Microtúbulos/enzimologia , Microtúbulos/genética , Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo
5.
Biochem Biophys Res Commun ; 643: 77-87, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36587525

RESUMO

Investigating novel mechanisms of neurite outgrowth via cytoskeleton is critical for developing therapeutic strategies against neural disorders. Rab3A is a vesicle-related protein distributed throughout the nervous system, but the detailed mechanism related to cytoskeleton remains largely unknown. Our previous reports show that spastin serves microtubule to regulate neurite outgrowth. Here, we asked whether Rab3A could function via modulating spastin during neuronal development. The results revealed that Rab3A colocalized with spastin in cultured hippocampal neurons. Immunoprecipitation assays showed that Rab3A physically interacted with spastin in rat brain lysates. Rab3A overexpression significantly induced spastin degradation; this effect was reversed by leupeptin- or MG-132- administration, suggesting the lysosomal and ubiquitin-mediated degradation system. Immunofluorescence staining further confirmed that Rab3A and spastin immune-colocalized with the lysosome marker lysotracker. In COS7 cells, Rab3A overexpression significantly downregulated spastin expression and abolished the spastin-mediated microtubule severing. Furthermore, overexpression inhibited while genetic knockdown of Rab3A promoted neurite outgrowth. However, this inhibitory effect on neurite outgrowth in hippocampal neurons could be reversed via co-transfection of spastin, indicating that Rab3A functions via its interaction protein spastin. In general, our data identify an interaction between Rab3A and spastin, and this interaction affects the protein stability of spastin and eliminates its microtubule severing function, thereby modulating neurite outgrowth.


Assuntos
Adenosina Trifosfatases , Paraplegia Espástica Hereditária , Animais , Ratos , Adenosina Trifosfatases/metabolismo , Neuritos/metabolismo , Crescimento Neuronal , Neurônios/metabolismo , Proteína rab3A de Ligação ao GTP , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/metabolismo , Espastina/metabolismo , Espastina/farmacologia
6.
World J Microbiol Biotechnol ; 39(8): 196, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37183209

RESUMO

The antagonistic Bacillus amyloliquefaciens HY2-1 was a marine microbiology that was isolated previously from the seabed silt of Beibu Gulf in China by dual culture with Penicillium digitatum. As a continuous study, the present work focused on evaluating the antimicrobial activity, identifying the produced active components, and revealing the fermentation characteristics of B. amyloliquefaciens HY2-1, respectively. It was found that B. amyloliquefaciens HY2-1 exhibited a broad-spectrum antimicrobial activity against the tested seven phytopathogenic fungi and five pathogenic bacteria by producing Bacillus lipopeptides such as fengycin A (C14 to C19 homologues) and surfactin (C14 and C15 homologues). Morphological observation of P. digitatum under light microscope, scanning electron microscopy, transmission electron microscopy, and fluorescence microscope inferred that B. amyloliquefaciens exerted the antagonistic activity by damaging the fungal cell membrane, thus inhibiting the mycelium growth and sporification of phytopathogenic fungi. As a marine microbiology, our results showed that B. amyloliquefaciens could survive and metabolize even at the culture condition with 110 g/L of NaCl concentration, and the produced antimicrobial compounds exhibited excellent thermostability and acid-alkali tolerance. The dynamic models were further constructed to theoretically analyze the fermentation process of B. amyloliquefaciens HY2-1, suggesting that the synthesis of antimicrobial compounds was coupled with both cell growth and cell biomass. In conclusion, the marine lipopeptides-producing B. amyloliquefaciens HY2-1 showed a promising prospect to be explored as a biocontrol agent for plant disease control of crops and postharvest preservation of fruits and vegetables, especially due to its outstanding stress resistance and the broad-spectrum and effective antagonist on various phytopathogenic fungi.


Assuntos
Anti-Infecciosos , Bacillus amyloliquefaciens , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Bacillus amyloliquefaciens/metabolismo , Fermentação , Cinética , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Lipopeptídeos/metabolismo
7.
Nurs Crit Care ; 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041106

RESUMO

BACKGROUND: Spinal fracture is a common traumatic condition in orthopaedics, accounting for 5%-6% of total body fractures, and is a high-risk factor for venous thromboembolism (VTE), which seriously affects patient prognosis. AIM: The aim of this study was to determine the impact of VTE prophylaxis on the prognosis of patients with spinal fractures in intensive care units (ICUs) and to provide a scientific basis for clinical treatment and nursing. DESIGN: A retrospective study of patients with spinal fractures from the multicenter eICU Collaborative Research Database. METHOD: The outcomes of this study were ICU mortality and in-hospital mortality. Patients were divided into the VTE prophylaxis (VP) and no VTE prophylaxis (NVP) groups according to whether they had undergone VTE prophylaxis during their ICU admission. The association between groups and outcomes were analysed using Kaplan-Meier (KM) survival curve, log-rank test and the Cox proportional-hazards regression model. RESULTS: This study included 1146 patients with spinal fractures: 330 in the VP group and 816 in the NVP group. KM survival curves and log-rank tests revealed that both ICU and in-hospital survival probabilities in the VP group were significantly higher than in the NVP group. After the Cox model was adjusted for all covariates, the hazard ratio for ICU mortality in the VP group was 0.38 (0.19-0.75); the corresponding value for in-hospital mortality in the VP group was 0.38 (0.21-0.68). CONCLUSIONS: VTE prophylaxis is associated with reduced ICU and in-hospital mortality in patients with spinal fractures in ICUs. More research is necessary to further define specific strategies and optimal timing for VTE prophylaxis. RELEVANCE TO CLINICAL PRACTICE: This study provides the basis that VTE prophylaxis may be associated with improved prognosis in patients with spinal fractures in ICUs. In clinical practice, an appropriate modality should be selected for VTE prophylaxis in such patients.

8.
Andrologia ; 54(1): e14287, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34755909

RESUMO

In this study, we aimed to investigate the effect of gap junction (GJ) on apoptosis of smooth muscle. Forty adult male guinea pigs were randomly divided into four groups with 10 guinea pigs in each group. Adeno-associated virus (AAV) and Gap27 were injected at the root of the corpus cavernosum. Two weeks later, the corpus cavernosum tissue was taken to be tested. The expression of Cx43 and α-SMC protein was detected by immunofluorescence and Western blotting. The content of corpus cavernosum smooth muscle was detected by Masson trichrome staining. Apoptosis was detected by TUNEL staining and Western blotting. The results showed that Gap27 did not affect Cx43 but decreased the expression of smooth muscle. The results of TUNEL staining and detection of apoptosis-related proteins showed that apoptosis was induced by Gap27. In addition, we found that corpus cavernosum injection of AAV could induce obvious apoptosis. In this study, we examined the effect of inhibition of gap junction on smooth muscle, and suggested that the decrease of gap junction function may be a potential mechanism of smooth muscle apoptosis.


Assuntos
Disfunção Erétil , Miócitos de Músculo Liso , Animais , Apoptose , Comunicação , Junções Comunicantes , Cobaias , Humanos , Masculino , Músculo Liso , Pênis , Ratos , Ratos Sprague-Dawley
9.
J Pediatr Nurs ; 64: e15-e23, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35125274

RESUMO

PROBLEM: Mental health issues in adolescents are public health concerns worldwide including China. However, there is a lack of research examining the role of parental absence status, life skills, and personality traits on the mental health of adolescents in rural China. METHOD: The purpose of this cross-sectional study was to examine the role of parental absence status, life skills, and personality traits on the mental health of adolescents in rural China. This study used self-developed demographic questionnaire, Mental Health Test (MHT), Middle School Student Life Skills Rating Scale, and Eysenck Personality Questionnaire. Binary logistic regression analyses were performed to examine the associated factors on different domains of MHT. RESULTS: Adolescents in rural China reported high proportion of mental health disorders (MHDs), including learning anxiety, sensitiveness, self-accusation, and physical symptoms tendency. Although 75.6% experienced parental absence, this was not associated with MHT after controlling for all other variables. Better mental health was correlated with life skills including communication skills, interpersonal morality, self-efficacy, and stress coping. The instability-neuroticism personality trait was positively associated with MHDs. DISCUSSION: Adolescents in rural China reported high positive rates of MHDs. Communication skills, interpersonal morality, self-efficacy, ability to cope with stress and Instability-neuroticism were important associated factors of MHDs. APPLICATION TO PRACTICE: Life skills and personality are two important factors that should be considered when assessing the mental health status of adolescents and formulating interventions.


Assuntos
Personalidade , Estado Epiléptico , Adolescente , China/epidemiologia , Estudos Transversais , Nível de Saúde , Humanos , Pais , Inquéritos e Questionários
10.
Molecules ; 27(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36144481

RESUMO

A large amount of hemp polysaccharides remain in industrial hemp residues (IHR) after cannabidiol extraction, resulting in the waste of resources. Therefore, the systematic study of hemp polysaccharides is beneficial to the development of IHR in the future. In this study, the extraction of industrial hemp residues polysaccharide (IHRPs) was optimized by single-factor experiment and orthogonal experimental design. The optimum heating extraction conditions were extraction temperature 98 °C, solid-liquid ratio 1:10, extraction time 1 h, number of successive extractions 2, and pH at 4. The extraction ratio and the polysaccharide content were 20.12 ± 0.55% and 12.35 ± 0.26% at the conditions, respectively. Besides, the best alcohol precipitation conditions were pumping with 2 L/h, stirring continuously, and ice-water bath for 4 h. The crude IHRPs was further purified by column chromatography and the polysaccharide/protein contents of purified IHRPs were 34.44% and 1.61%. IHRPs was mainly made up of ten monosaccharides and some non-sugar components including organic acids, flavonoids, steroids, and glycoside. The FT-IR demonstrated the polysaccharide skeleton of IHRPs. Moreover, the DPPH and ABTS scavenging rate of IHRPs were 76.00% and 99.05% at the concentrations of 1 mg/mL. IHRPs could promote the epidermal cells proliferation and healing of cell scratches. Meanwhile, IHRPs could promoted the expression of anti-aging-related genes. Overall, IHRPs could be a desirable natural source of antioxidants and anti-aging products in many aspects.


Assuntos
Canabidiol , Cannabis , Antioxidantes/química , Flavonoides , Glicosídeos , Gelo/análise , Monossacarídeos/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(11): 1298-1305, 2021 Nov 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-34911866

RESUMO

Adverse childhood experience (ACE) is potentially negative experience that occurs between 0 and 18 years old. The ACE adolescents have prominent mental health problems such as emotional regulation disorder, unstable interpersonal relationship, poor coping ability, and cognitive dysfunction. Until now, the factors affecting the mental health of ACE adolescents are not clear, but it is certain that the ecosystem in which ACE adolescents life affects their mental health. Specifically, the parent-child relationship, the school environment, the peer relationship in the micro-system, and the interaction between the parent-child relationship and other interpersonal relationship in the meso-system have been confirmed to be significantly related to the mental health of ACE adolescents. In the appearance system, the neighborhood cohesion, the level of family income, the educational level of parents and the different social and cultural background in the macro-system all have different degrees of impact on the development of ACE adolescents' psychological behaviors. In the diachronic system, the time and frequency of suffering from ACE have different effects on the mental health regarding the ACE adolescents.


Assuntos
Experiências Adversas da Infância , Adolescente , Criança , Pré-Escolar , Ecossistema , Nível de Saúde , Humanos , Lactente , Recém-Nascido , Saúde Mental , Pais
12.
Neurobiol Dis ; 146: 105133, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33049318

RESUMO

Dendritic spines are specialized structures involved in neuronal processes on which excitatory synaptic contact occurs. The microtubule cytoskeleton is vital for maintaining spine morphology and mature synapses. Spastin is related to microtubule-severing proteases and is involved in synaptic bouton formation. However, it is not yet known if spastin can be modified by Small Ubiquitin-like Modifier (SUMO) or how this modification regulates dendritic spines. Spastin was shown to be SUMOylated at K427, and its deSUMOylation promoted microtubule stability. In addition, SUMOylation of spastin was shown to affect signalling pathways associated with long term synaptic depression. SUMOylated spastin promoted the development of dendrites and dendritic spines. Moreover, SUMOylated spastin regulated endocytosis and affected the transport of the AMPA receptor, GluA1. Our findings suggest that SUMOylation of spastin promotes GluA1 internalization and regulates dendritic spine morphology through targeting of microtubule dynamics.


Assuntos
Espinhas Dendríticas/metabolismo , Microtúbulos/metabolismo , Receptores de AMPA/metabolismo , Espastina/metabolismo , Sumoilação/fisiologia , Animais , Depressão Sináptica de Longo Prazo/fisiologia , Neurônios/metabolismo , Ratos Sprague-Dawley , Espastina/farmacologia , Sinapses/fisiologia
13.
Appl Opt ; 59(14): 4557-4565, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32400435

RESUMO

A comprehensive analysis on assembly of dielectric-filled 3D crossed compound parabolic concentrator (CCPC) and concentrator photovoltaic (CPV) module is presented by embracing the consideration of spectral irradiance, incident angles, and breakdown optical losses. The theoretical modeling is supported by experimental validation to evaluate the optical efficiency of the CCPC-CPV module. From our analysis, Fresnel reflection loss of 11.27%, absorption loss of 11.59%, and other losses of 4.79% are obtained to reach the total loss of 27.65% or equivalent solar concentration ratio (SCR) of 4.65 suns out of a geometrical concentration ratio (GCR) of 5.998 suns. Then, indoor and outdoor measurements prove the actual SCR of 4.57 and 4.48 suns, respectively.

14.
Molecules ; 25(17)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847017

RESUMO

Quinoa is known for its rich nutrients and bioactive compounds. In order to elucidate the preliminary structural characteristics and biological activity of polysaccharides from quinoa (QPs), five crude polysaccharides (QPE50, QPE60, QPE70, QPE80 and QPE90) were successively fractionated by gradient ethanol, and their physicochemical properties, antioxidant and antidiabetic activities were analyzed. The results implied that their total sugar contents were 52.82%, 63.69%, 67.15%, 44.56%, and 41.01%, and their weight-average molecular weights were 13,785 Da, 6489 Da, 4732 Da, 3318 Da, and 1960 Da, respectively. Glucose was a predominantly monosaccharide in these QPs, which together in QPE50, QPE60, QPE70, QPE80, and QPE90, respectively, made up 94.37%, 87.92%, 92.21%, 100%, and 100% of the total polysaccharide. Congo red test showed that all five QPs contained triple-helix structure. The Fourier transform-infrared spectroscopy (FT-IR) and X-ray diffractometry (XRD) results suggest that the QPs form a semi-crystalline polymer constituted typical functional groups of polysaccharide including CO, CH and OH. The thermogravimetric analysis (TGA) of QPs showed that weight loss was at about 200 °C and 320 °C. The observation from scanning electron microscope (SEM) and atomic force microscope (AFM) image indicated that the morphology of QPs exhibited spherical shape. Antioxidant and antidiabetic assay exhibited that all five QPs samples had certain antioxidant and antidiabetic activities, and QPE90 showed the best antioxidant and antidiabetic activity. Overall, QPs present a promising natural source of food antioxidants and antidiabetic agents.


Assuntos
Antioxidantes , Chenopodium quinoa/química , Hipoglicemiantes , Polissacarídeos , Sementes/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Polissacarídeos/química , Polissacarídeos/isolamento & purificação
15.
Molecules ; 23(6)2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29843405

RESUMO

Aspergoterpenins A⁻D (1⁻4), four new bisabolane sesquiterpenoid derivatives, were obtained from the endophytic fungus, Aspergillus versicolor, together with eight known compounds (5⁻12), and their structures were elucidated by a comprehensive analysis of their NMR (Nuclear Magnetic Resonance), MS (Mass Spectrum) and CD (Circular Dichroism) spectra. Aspergoterpenin A (1) was the first example with a characteristic ketal bridged-ring part in the degraded natural bisabolane-type sesquiterpene structures. The compounds 1⁻12 displayed no significant activities against four cancer cell lines (A549, Caski, HepG2 and MCF-7). Further, the antimicrobial activities to Erwinia carotovora sub sp. Carotovora were evaluated, and the results showed that compounds 1⁻12 displayed antimicrobial activities with MIC values ranging from 15.2 to 85.2 µg/mL.


Assuntos
Anti-Infecciosos/farmacologia , Aspergillus/química , Pectobacterium carotovorum/efeitos dos fármacos , Sesquiterpenos/farmacologia , Células A549 , Anti-Infecciosos/química , Linhagem Celular Tumoral , Células Hep G2 , Humanos , Células MCF-7 , Testes de Sensibilidade Microbiana , Estrutura Molecular , Sesquiterpenos/química
16.
Chemistry ; 23(34): 8252-8261, 2017 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-28421629

RESUMO

Heteroatom doping is a promising approach to improve the properties of carbon materials for customized applications. Herein, a series of Cu catalysts supported on boron-doped carbon nanotubes (Cu/xB-CNTs) were prepared for the hydrogenation of dimethyl oxalate (DMO) to ethanol. The structure and chemical properties of boron-doped catalysts were characterized by XRD, TEM, N2 O pulse adsorption, CO chemisorption, H2 temperature-programmed reduction, and NH3 temperature-programmed desorption, which revealed that doping boron into CNT supports improved the Cu dispersion, strengthened the interaction of Cu species with the CNT support, introduced more surface acid sites, and increased the surface area of Cu0 and especially Cu+ sites. Consequently, the catalytic activity and stability of the catalysts were greatly enhanced by boron doping. 100 % DMO conversion and 78.1 % ethanol selectivity could be achieved over the Cu/1B-CNTs catalyst, the ethanol selectivity of which was almost 1.7 times higher than that of the catalyst without boron doping. These results suggest that doping CNTs with boron is an efficient approach to improve the catalytic performance of CNT-based catalysts for hydrogenation of DMO. The boron-doped CNT-based catalyst with improved ethanol selectivity and catalytic stability will be helpful in the development of efficient Cu catalysts supported on non-silica materials for selective hydrogenation of DMO to ethanol.

17.
Neural Plast ; 2017: 8197085, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28758034

RESUMO

Amyloid-ß (Aß) plays an important role in Alzheimer's disease (AD), as oligomeric Aß induces loss of postsynaptic AMPA receptors (AMPARs) leading to cognitive deficits. The loss of postsynaptic AMPARs is mediated through the clathrin-dependent endocytosis pathway, in which endophilin2 is one of the important regulatory proteins. Endophilin2, which is enriched in both the pre- and postsynaptic membrane, has previously been reported to be important for recycling of synaptic vesicles at the presynaptic membrane. However, the role of endophilin2 in oligomeric Aß-induced postsynaptic AMPAR endocytosis is not well understood. In this study, we show that endophilin2 does not affect constitutive AMPAR endocytosis. Endophilin2 knockdown, but not overexpression, resisted oligomeric Aß-induced AMPAR dysfunction. Moreover, endophilin2 colocalized and interacted with GluA1, a subunit of AMPAR, to regulate oligomeric Aß-induced AMPAR endocytosis. Thus, we have determined a role of endophilin2 in oligomeric Aß-induced postsynaptic AMPAR dysfunction, indicating possible directions for preventing the loss of AMPARs in cognitive impairment and providing evidence for the clinical treatment of AD.


Assuntos
Aciltransferases/metabolismo , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Endocitose , Fragmentos de Peptídeos/metabolismo , Receptores de AMPA/metabolismo , Animais , Hipocampo/metabolismo , Humanos , Neurônios/metabolismo , Ratos Sprague-Dawley
18.
Opt Express ; 23(15): A841-57, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26367685

RESUMO

This paper presents an approach to optimize the electrical performance of dense-array concentrator photovoltaic system comprised of non-imaging dish concentrator by considering the circumsolar radiation and slope error effects. Based on the simulated flux distribution, a systematic methodology to optimize the layout configuration of solar cells interconnection circuit in dense array concentrator photovoltaic module has been proposed by minimizing the current mismatch caused by non-uniformity of concentrated sunlight. An optimized layout of interconnection solar cells circuit with minimum electrical power loss of 6.5% can be achieved by minimizing the effects of both circumsolar radiation and slope error.

19.
Environ Sci Technol ; 49(20): 12363-71, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26384045

RESUMO

Reduction of Cr(VI) is often deemed necessary to detoxify chromium contaminants; however, few investigations utilized this reaction for the purpose of treating other industrial wastewaters. Here a widely used Cr(VI)-sulfite reaction system was upgraded to simultaneously transform multiple pollutants, namely, the reduction of Cr(VI) and oxidation of sulfite and other organic/inorganic pollutants in an acidic solution. As(III) was selected as a probe pollutant to examine the oxidation capacity of a Cr(VI)-sulfite system. Both (•)OH and SO4(•-) were considered as the primary oxidants for As(III) oxidation, based on the results of electron spin resonance, fluorescence spectroscopy, and specific radicals quenching. As(III)-scavenging, oxidative radicals greatly accelerated Cr(VI) reduction and simultaneously consumed less sulfite. In comparison with a Cr(VI)-H2O2 system with 50 µM Cr(VI), Cr(VI), the sulfite system had excellent performance for both As(III) oxidation and Cr(VI) reduction at pH 3.5. Moreover, in this escalated process, less sulfite was required to reduce Cr(VI) than the traditional Cr(VI) reduction by sulfite process. This effectively improves the environmental compatibility of this Cr(VI) detoxification process, alleviating the potential for SO2 release and sulfate ion production in water. Generally, this study provides an excellent example of a "waste control by waste" strategy for the detoxification of multiple industrial pollutants.


Assuntos
Cromo/química , Sulfitos/química , Poluentes Químicos da Água/química , Peróxido de Hidrogênio/química , Oxidantes/química , Oxirredução , Águas Residuárias/química
20.
Neural Plast ; 2015: 371496, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26682072

RESUMO

Endophilin isoforms perform distinct characteristics in their interactions with N-type Ca(2+) channels and dynamin. However, precise functional differences for the endophilin isoforms on synaptic vesicle (SV) endocytosis remain unknown. By coupling RNA interference and electrophysiological recording techniques in cultured rat hippocampal neurons, we investigated the functional differences of three isoforms of endophilin in SV endocytosis. The results showed that the amplitude of normalized evoked excitatory postsynaptic currents in endophilin1 knockdown neurons decreased significantly for both single train and multiple train stimulations. Similar results were found using endophilin2 knockdown neurons, whereas endophilin3 siRNA exhibited no change compared with control neurons. Endophilin1 and endophilin2 affected SV endocytosis, but the effect of endophilin1 and endophilin2 double knockdown was not different from that of either knockdown alone. This result suggested that endophilin1 and endophilin2 functioned together but not independently during SV endocytosis. Taken together, our results indicate that SV endocytosis is sustained by endophilin1 and endophilin2 isoforms, but not by endophilin3, in primary cultured hippocampal neurons.


Assuntos
Aciltransferases/fisiologia , Endocitose , Hipocampo/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neurônios/fisiologia , Vesículas Sinápticas/fisiologia , Aciltransferases/metabolismo , Animais , Células Cultivadas , Potenciais Pós-Sinápticos Excitadores , Células HEK293 , Hipocampo/enzimologia , Hipocampo/metabolismo , Humanos , Proteínas do Tecido Nervoso/metabolismo , Neurônios/enzimologia , Neurônios/metabolismo , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/fisiologia , Ratos , Ratos Sprague-Dawley
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