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1.
J Environ Sci (China) ; 101: 361-372, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33334531

RESUMO

Chemical speciation can fundamentally affect the potential toxicity and bioavailability of heavy metals. The transformation of heavy metal speciation and change of bioavailability were investigated in an anaerobic digestion (AD) system using four different substrates (pig manure (PM), cattle manure (CAM), chicken manure (CHM) and rice straw (RS)). The results obtained indicated that the total contents of heavy metals in PM, CHM and CAM were higher than in RS and decreased in the order Zn > Cu > Ni > Pb > As > Cd in all substrates. Moreover, the speciation with the largest proportion for each heavy metal was the same both in the different substrates and the biogas residues. Among them, Zn, Ni, Cd and As were mainly in the reducible fraction (F2), while Cu was mainly in the oxidizable fraction (F3) and Pb occurred predominantly in the residual fraction (F4). Our results further indicated that the AD process had a greater effect on the speciation of heavy metals in CHM and PM, but less on CAM and RS. The rates of change in bioavailability followed the order PM > CHM > CAM > RS. Changes in organic matter, humic acid or local metal ion environment as a result of AD were inferred as likely mechanisms leading to the transformation of heavy metal speciation. These results enhanced our understanding of the behavior of heavy metals in AD and provided a new perspective for the treatment and disposal of the substrates.


Assuntos
Metais Pesados , Anaerobiose , Animais , Disponibilidade Biológica , Bovinos , Substâncias Húmicas , Esterco , Suínos
2.
Brain Behav ; 13(7): e3062, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37161559

RESUMO

BACKGROUND: The discovery of the glymphatic system and meningeal lymphatic vessels challenged the traditional view regarding the lack of a lymphatic system in the central nervous system. It is now known that the intracranial lymphatic system plays an important role in fluid transport, macromolecule uptake, and immune cell trafficking. Studies have also shown that the function of the intracranial lymphatic system is significantly associated with neurological diseases; for example, an impaired intracranial lymphatic system can lead to Tau deposition and an increased lymphocyte count in the brain tissue of mice with subarachnoid hemorrhage. METHODS: In this study, we assessed the changes in the intracranial lymphatic system after intracerebral hemorrhage and the regulatory effects of repeated transcranial magnetic stimulation on the glymphatic system and meningeal lymphatic vessels in an intracerebral hemorrhage (ICH) model of male mice. Experimental mice were divided into three groups: Sham, ICH, and ICH + repeated transcranial magnetic stimulation (rTMS). Three days after ICH, mice in the ICH+rTMS group were subjected to rTMS daily for 7 days. Thereafter, the function of the intracranial lymphatic system, clearance of RITC-dextran and FITC-dextran, and neurological functions were evaluated. RESULTS: Compared with the Sham group, the ICH group had an impaired glymphatic system. Importantly, rTMS treatment could improve intracranial lymphatic system function as well as behavioral functions and enhance the clearance of parenchymal RITC-dextran and FITC-dextran after ICH. CONCLUSION: Our results indicate that rTMS can abrogate ICH-induced brain parenchymal metabolite clearance dysfunction by regulating intracranial lymphatic drainage.


Assuntos
Dextranos , Estimulação Magnética Transcraniana , Masculino , Camundongos , Animais , Dextranos/metabolismo , Hemorragia Cerebral , Encéfalo
3.
J Phys Condens Matter ; 32(45): 455703, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32688349

RESUMO

Negative thermal expansion (NTE) is an abnormal physical behavior that has promising applications for high precision thermal control. Since Prussian blue analogues have the two central linking atoms of -C≡N-, they have large structure flexibility and are suitable to explore new NTE materials. However, understanding the nature of structure flexibility from the point of view of chemical bonding is important and urgent. Here, we adopt for the first time first-principles calculations to predict that the cubic TiCo(CN)6 and ScCo(CN)6 have NTE behavior. The calculated results for M in MCo(CN)6 (M = Fe, Ti and Co) indicated that the Sc-N bond is the strongest, but with the weakest direction dependence among the M-N bonds in the three systems. The lattice dynamics calculations results revealed that the low-frequency phonon vibration modes for NTE in MCo(CN)6 have much stronger relationship with the M-N bond feature. The present work reveals the important role of the related bond in the NTE open-framework materials.

4.
Clin Neurol Neurosurg ; 198: 106172, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32942133

RESUMO

BACKGROUND: Although several risk factors of the multiple intracranial aneurysms (MIAs) formation has been reported, the results are controversial. We aimed to find out the risk factors of MIAs formation by analyzing our clinic data combined with a meta-analysis. MATERIAL AND METHODS: A retrospective review work of medical records for the patients with aneurysms was undertaken. Univariate analysis was used to examine all mentioned variables. Binary logistic regression analysis was used to identify the risk factors of MIAs formation. RESULTS: In the retrospective review work, a total of 565 patients with aneurysm were included in this study. Of these 565 participants, 449 patients suffered SIAs and 116 patients suffered MIAs. Univariate analysis showed a significant difference in terms of female, cigarette smoking, family history of hypertension, and primary hypertension between the SIAs and MIAs group. The binary logistic regression analysis showed that the female (OR = 1.624), primary hypertension (OR = 1.563), and family history of hypertension (OR = 2.496) were independent risk factors of the formation of MIAs (for each P < 0.05). With regard to the meta-analysis results, it revealed that there was significant difference in the rates of female (P < 0.001), cigarette smoking (P < 0.001), primary hypertension (P = 0.001), and higher age (P = 0.011) among the MIAs patients. CONCLUSIONS: A higher rate of the formation of MIAs is closely associated with the elder and female. Patients with hypertension history, cigarette smoking, and family primary hypertension history also affected the formation of MIAs, these risk factors should be a guard against.


Assuntos
Aneurisma Intracraniano/epidemiologia , Feminino , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Aneurisma Intracraniano/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
5.
Chem Biol Drug Des ; 94(2): 1488-1493, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30932330

RESUMO

A series of compounds similar to Pracinostat that contained benzimidazole ring and N-hydroxyacrylamide attached at 5- or 6-position were designed, synthesized, and evaluated as HDAC inhibitors. It was interesting to find that the corresponding derivative 1 with N-hydroxyacrylamide attached at 5-position was a potent HDAC inhibitor while the others at 6-position were not. This is the first time to demonstrate the position difference plays important role in the HDAC inhibitory activities of the cinnamic hydroxamates.


Assuntos
Benzimidazóis , Inibidores de Histona Desacetilases , Benzimidazóis/química , Benzimidazóis/farmacologia , Células HeLa , Desacetilase 6 de Histona/antagonistas & inibidores , Desacetilase 6 de Histona/metabolismo , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Humanos
7.
World Neurosurg ; 95: 341-347, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27544338

RESUMO

OBJECTIVE: To study the curative effect and prognosis of patients with basal ganglia cerebral hemorrhages treated using a transcortical-sulcus approach and compare with results obtained using the traditional cerebral cortex approach. METHODS: Clinical data were collected from 106 patients with hypertensive hemorrhage in the basal ganglia who were treated using either a transcortical-sulcus approach or traditional cerebral cortex approach. The rate of rehemorrhage, incidence of epilepsy, and 3-month efficacy (defined by an activities of daily living score) rate between the 2 groups were compared. RESULTS: The 3-month efficacy rates of patients treated using the transcortical-sulcus and traditional cerebral cortex surgical approaches were 78.4% and 60%, respectively (P < 0.05). The incidence of epilepsy was lower in the transcortical-sulcus approach group compared with the traditional approach group, and significant differences were detected between the 2 groups (P < 0.05). CONCLUSIONS: The transcortical-sulcus approach can significantly improve the prognosis of patients with intracerebral hemorrhages in the basal ganglia and reduce the incidence of postoperative seizures.


Assuntos
Gânglios da Base/cirurgia , Córtex Cerebral/cirurgia , Hipertensão/cirurgia , Hemorragia Intracraniana Hipertensiva/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Gânglios da Base/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Hipertensão/diagnóstico por imagem , Hemorragia Intracraniana Hipertensiva/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/prevenção & controle , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/cirurgia , Estudos Retrospectivos , Convulsões/diagnóstico por imagem , Convulsões/prevenção & controle
8.
Adv Mater ; 25(27): 3664-9, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23696475

RESUMO

Supramolecular steric hindrance designs make pyrene-functionalized spiro[fluorene-9,7'-dibenzo[c,h]acridine]-5'-one (Py-SFDBAO) assemble into 2D nanostructures that facilitate aqueous phase large-area synthesis of high-quality and uniform crystalline thin films. Thin-film diodes using aqueous nanosheets as active layers exhibit a non-volatile bistable electrical switching feature with ON/OFF ratios of 6.0 × 10(4) and photoswitching with conductive gains of 10(2) -10(3). Organic nanosheets are potentially key components for eco-friendly aqueous dispersed organic nano-inks in the application of printed and flexible electronics.


Assuntos
Nanoestruturas/química , Hidrocarbonetos Policíclicos Aromáticos/química , Compostos de Espiro/química , Desenho de Equipamento , Modelos Moleculares , Estrutura Molecular , Hidrocarbonetos Policíclicos Aromáticos/síntese química , Compostos de Espiro/síntese química , Água/química
9.
ACS Nano ; 6(4): 3027-33, 2012 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-22420637

RESUMO

We report a green and efficient method for chemoselective deoxidization of graphene oxide via the ultraviolet irradiation catalyzed with 2,2,6,6-tetramethyl-4-piperidinol. While the sp(2)-hybridized oxygen functional groups are removed after the reduction, the epoxy and hydroxyl groups are retained in the chemoselectively reduced graphene oxide (CrGO). The obtained CrGO nanosheets exhibit the high solubility and excellent electronic stability, which allows for the fabrication of thin film devices through a solution processing. As a proof of concept, a CrGO-based write-once-read-many-times memory device with the desirable stability and long-time operation is fabricated.


Assuntos
Aminas/química , Técnicas de Química Sintética/métodos , Grafite/química , Química Verde/métodos , Óxidos/química , Óxidos/síntese química , Processos Fotoquímicos , Catálise , Modelos Moleculares , Conformação Molecular , Oxirredução , Piperidinas/química , Solventes/química , Especificidade por Substrato
10.
ACS Nano ; 6(6): 5309-19, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22575153

RESUMO

Nonplane molecules with multiple large aromatic planes could be promising candidates to form various polyhedral micro/nanocrystals by manipulating the different π···π stacking, tuning the cohesive energies of crystal facets, and controlling the kinetic growth process. Spirocyclic aromatic hydrocarbons (SAHs) not only have two cross-shaped aromatic planes but also offer the feature of supramolecular steric hindrance, making it favorable for the heterogeneous kinetic growth into highly symmetric polyhedra. Herein, we report that a novel SAH compound, spiro[fluorene-9,7'-dibenzo[c,h]acridine]-5'-one (SFDBAO), can self-assemble into various monodispersed shapes such as hexahedra, octahedra, and decahedra through the variation of either different types of surfactants, such as Pluronic 123 (P123) and cetyltrimethyl ammonium bromide (CTAB), or growth parameters. In addition, the possible mechanism of crystal facet growth has been proposed according to the SEM, XRD, TEM, and SAED characterization of organic polyhedral micro/nanocrystals. The unique cruciform-shaped SAHs have been demonstrated as fascinating supramolecular synthons for various highly symmetric polyhedral assembling.


Assuntos
Nanopartículas/química , Nanopartículas/ultraestrutura , Hidrocarbonetos Policíclicos Aromáticos/síntese química , Cristalização/métodos , Cinética , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
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