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1.
Neurobiol Dis ; 179: 106066, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36889483

RESUMO

Although both are myeloid cells located surrounding cerebral vasculature, vessel-associated microglia (VAM) and perivascular macrophages (PVMs) can be distinguished by their distinct morphologies, signatures and microscopic location. As key component of neuro-glia-vascular unit (NGVU), they play prominent roles in neurovasculature development and pathological process of various central nervous system (CNS) diseases, including phagocytosis, angiogenesis, vessel damage/protection and blood flow regulation, therefore serving as potential targets for therapeutics of a broad array of CNS diseases. Herein, we will provide a comprehensive overview of heterogeneity of VAM/PVMs, highlight limitations of current understanding in this field, and discuss possible directions of future investigations.


Assuntos
Doenças do Sistema Nervoso Central , Microglia , Humanos , Microglia/fisiologia , Encéfalo/patologia , Macrófagos , Fagocitose , Doenças do Sistema Nervoso Central/patologia
2.
Polymers (Basel) ; 13(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34833172

RESUMO

In this paper, we describe a comprehensive study of the thermoresponsive properties of statistic copolymers and multiblock copolymers synthesized by poly(glycidol)s (PG) and poly(ethyl glycidyl ether) (PEGE) with different copolymerization methods. These copolymers were first synthesized by ring-opening polymerization (ROP), which was initiated by tert-butylbenzyl alcohol (tBBA) and 1-tert-butyl-4,4,4-tris(dimethylamino)-2,2-bis[tris(dimethylamino)phosphoranylidenamino]-2Λ5,4Λ5-catenadi(phosphazene) (t-Bu-P4) as the catalyst, and then the inherent protective groups were removed to obtain the copolymers without any specific chain end groups. The thermoresponsive property of the statistic copolymer PGx-stat-PEGEy was compared with the diblock copolymer PGx-b-PEGEy, and the triblock copolymers were compared with the pentablock copolymers. Among them, PG-stat-PEGE, PG-b-PEGE-b-PG-b-PEGE-b-PG, and PEGE-b-PG-b-PEGE-b-PG-b-PEGE, and even the specific ratio of PEGE-b-PG-b-PEGE, exhibited LCST-type phase transitions in water, which were characterized by cloud point (Tcp). Although the ratio of x to y affected the value of the Tcp of PGx-stat-PEGEy, we found that the disorder of the copolymer has a decisive effect on the phase-transition behavior. The phase-transition behaviors of PG-b-PEGE, part of PEGE-b-PG-b-PEGE, and PG-b-PEGE-b-PG copolymers in water present a two-stage phase transition, that is, firstly LCST-type and then the upper critical solution temperature (UCST)-like phase transition. In addition, we have extended the research on the thermoresponsive properties of EGE homopolymers without specific α-chain ends.

3.
Chemistry ; 27(44): 11468-11476, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34002909

RESUMO

The reasonable design of the precursor of a carbon-based nanocatalyst is an important pathway to improve catalytic performance. In this study, a simple solvothermal method was used to synthesize [Cu(TPT)(2,5-tdc)] ⋅ 2H2 O (Cu-MOF), which contains N and S atoms, in one step. Further in-situ carbonization of the Cu-MOF as the precursor was used to synthesize Cu/Cux S-embedded N,S-doped porous carbon (Cu/Cux S/NSC) composites. The catalytic activities of the prepared Cu/Cux S/NSC were investigated through catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The results show that the designed Cu/Cux S/NSC has exceptional catalytic activity and recycling stability, with a reaction rate constant of 0.0256 s-1 , and the conversion rate still exceeds 90 % after 15 cycles. Meanwhile, the efficient catalytic reduction of dyes (CR, MO, MB and RhB) confirmed its versatility. Finally, the active sites of the Cu/Cux S/NSC catalysts were analyzed, and a possible multicomponent synergistic catalytic mechanism was proposed.

4.
Acta Psychol (Amst) ; 207: 103084, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32408141

RESUMO

A growing body of evidence suggested that time can be represented separately either on the lateral, sagittal or vertical axis. However, it is still not clear whether these mental time lines from different origins could co-exist, or compete with each other such that if one is selected, the others are inhibited? The present study addressed this question using a multi-dimensional free-choice paradigm with Mandarin speakers in three experiments. The results showed that significant spatial-temporal congruency effects were found both on the lateral and sagittal/vertical axes in the horizontal/coronal plane either in a temporal judgment relevant or irrelevant task. By contrast, the spatial-temporal congruency effects did not appear at the same time on the sagittal and vertical axes in the sagittal plane. These results supported that lateral mental time line could co-exist with the other two, while sagittal and vertical mental time lines could not co-exist with each other. This finding implied that the space-time mapping mechanism is different between the lateral axis and the sagittal and vertical axes, whereas it is the same for the latter two axes.


Assuntos
Percepção Espacial , Percepção do Tempo , Humanos , Julgamento , Tempo
5.
Neurosci Lett ; 686: 101-105, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30193796

RESUMO

A number of near-infrared spectroscopy (NIRS) studies in schizophrenia have shown that there is a significant dysfunction of the prefrontal cortex (PFC) in patients with schizophrenia, but it remains unclear how atypical antipsychotics affect the function of the PFC. To investigate the changes in brain activation patterns in schizophrenia who accepted antipsychotic treatment, we used NIRS to measure the hemodynamic changes of the PFC in patients with schizophrenia at the time of enrollment and after 4 weeks of treatment during a verbal fluency task (VFT). We included 16 schizophrenia and 17 sex- and age- matched healthy controls. Compared with the healthy controls, the VFT performance was significantly worse in patients with schizophrenia, as was the activation of the PFC. Furthermore, after 4 weeks of treatment, there was no significant improvement in VFT performance and the activation of the PFC in schizophrenia. Our results suggest that the function of the PFC and cognitive skills in schizophrenia were significantly impaired and do not improve from a short-term treatment of atypical antipsychotics.


Assuntos
Antipsicóticos/farmacologia , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho , Comportamento Verbal/fisiologia , Adulto , Feminino , Neuroimagem Funcional/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Córtex Pré-Frontal/efeitos dos fármacos , Esquizofrenia/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Comportamento Verbal/efeitos dos fármacos , Adulto Jovem
6.
Nanoscale Res Lett ; 13(1): 55, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29460120

RESUMO

The interlamellar spacing of layered double hydroxides (LDHs) was enlarged by dodecyl sulfonate ions firstly, and then, (3-aminopropyl)triethoxysilane (APS) was chemically grafted (APS/LDHs). The structural characteristics and thermal stability of these prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), reflectance Fourier transform infrared spectrometer (FTIR), thermogravimetric analysis (TG), and elemental analysis (EA) respectively. The CO2 adsorption performance was investigated adopting TG and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The results presented that the CO2 adsorption capacity on APS/LDHs was as high as 90 mg/g and showed no obvious reduction during a five cyclic adsorption-desorption test, indicating its superior performance stability. The DRIFTS results showed that both carbamates and weakly bounded CO2 species were generated on APS/LDHs. The weakly adsorbed species was due to the different local chemical environment for CO2 capture provided by the surface moieties of LDHs like free silanol and hydrogen bonds.

7.
PLoS One ; 10(3): e0121147, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25793386

RESUMO

BACKGROUND AND OBJECTIVES: Methylenetetrahydrofolate reductase (MTHFR) polymorphism may be a risk factor for male infertility. However, the epidemiologic studies showed inconsistent results regarding MTHFR polymorphism and the risk of male infertility. Therefore, we performed a meta-analysis of published case-control studies to re-examine the controversy. METHODS: Electronic searches of PubMed, EMBASE, Google Scholar and China National Knowledge Infrastructure (CNKI) were conducted to select eligible literatures for this meta-analysis (updated to June 19, 2014). According to our inclusion criteria and the Newcastle-Ottawa Scale (NOS), only high quality studies that observed the association between MTHFR polymorphism and male infertility risk were included. Crude odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of association between the MTHFR polymorphism and male infertility risk. RESULTS: Twenty-six studies involving 5,575 cases and 5,447 controls were recruited. Overall, MTHFR 677C>T polymorphism showed significant associations with male infertility risk in both fixed effects (CT+TT vs. CC: OR = 1.34, 95% CI: 1.23-1.46) and random effects models (CT+TT vs. CC: OR = 1.39, 95% CI: 1.19-1.62). Further, when stratified by ethnicity, sperm concentration and control sources, the similar results were observed in Asians, Caucasians, Azoo or OAT subgroup and both in population-based and hospital-based controls. Nevertheless, no significant association was only observed in oligo subgroup. CONCLUSIONS: Our results indicated that the MTHFR polymorphism is associated with an increased risk of male infertility. Further well-designed analytical studies are necessary to confirm our conclusions and evaluate gene-environment interactions with male infertility risk.


Assuntos
Predisposição Genética para Doença , Infertilidade Masculina/enzimologia , Infertilidade Masculina/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único/genética , Etnicidade/genética , Humanos , Masculino , Viés de Publicação , Fatores de Risco , Espermatozoides/metabolismo
8.
Ying Yong Sheng Tai Xue Bao ; 15(7): 1171-3, 2004 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-15506092

RESUMO

The bioactivity of Myoporum bontioides extracts to Plutella xylostella was studied with IIPC as evaluated index. The results showed that petroleum ether and chloroform extracts had a higher activity than ethyl acetate and alcohol extracts. At 0.01 gDW x ml(-1), the ODR of petroleum ether and chloroform extracts was 84.69% and 79.90%, and 76.47% and 45.70% after treated 1d and 3d, while the IIPC was 0.1565 and 0.2055, respectively. Provided with a higher concentration of 0.05 gDW x ml(-1), the ODR was 88.52% and 72.25%, and 87.33%, 58.37%, while the IIPC was 0.1125 and 0.2620, respectively. From the chloroform extract of Myopdrum Bontioides, three flavonoids, 2, 3-dihydro-5, 7-dihydroxy-2-phenyl-4H-1-Benzopyran-4-one (I), 3, 5, 7-trihydroxy-2-phenyl-4H-1-Benzopyran-4-one (II) and 5, 7-dihydroxy-3-methoxy-2-(4-methoxyphenyl)-4H-1-Benzopyran-4-one (III), were isolated, and their structure were identified based on the analyses of physical and spectrum data. Among these compounds, (II) had a better bioactivity to Plutella xylostella.


Assuntos
Flavonoides/farmacologia , Controle de Insetos , Mariposas/crescimento & desenvolvimento , Myoporum/química , Animais , Flavonoides/isolamento & purificação , Extratos Vegetais/farmacologia
9.
Ying Yong Sheng Tai Xue Bao ; 15(1): 149-52, 2004 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15139209

RESUMO

This study showed that the volatile oils from Myoporum bontioides had a significant repellent action on Plutella xylostella. When Plutella xylostella adults entered into the 4-arm selective olfactometer, the preferred times and average staying duration, in the order from more to less, were 3, 1, 4, and 2 arms, which showed a tendency of keeping away from the treatment arms. The males were more sensitive to the volatile oils than the females, when the velocity of flow was 200 ml.min-1. On the first day of the 3rd bioassay, the oviposition deterrent rate and IIPC of the volatile oils on Plutella xylostella adults was 94.48% and 0.0552, respectively. A liquid component of the volatile oils from Myoporum bontioides was isolated, purified, and identified as myoporone.


Assuntos
Mariposas , Myoporum/química , Óleos Voláteis/farmacologia , Controle Biológico de Vetores , Animais , Feminino , Masculino
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