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1.
J Hazard Mater ; 416: 125930, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492860

RESUMO

The pollution of heavy metals and organic compounds has received increased attention in recent years. In the current study, a novel biochar-based iron oxide composite (FeYBC) was successfully synthesized using pomelo peel and ferric chloride solution through one-step process at moderate temperature. Results clearly demonstrate that FeYBC exhibited more efficient removal of Cr(VI) and/or phenol compared with the pristine biochar, and the maximum adsorption amounts of Cr(VI) and phenol by FeYBC could reach 24.37 and 39.32 mg g-1, respectively. A series of characterization data suggests that several iron oxides such as Fe2O3, Fe0, FeOOH and Fe3O4 were formed on the FeYBC surface as well as oxygen-containing groups. Thermodynamics study indicates that Cr(VI) and phenol adsorption by FeYBC were endothermic and exothermic processes, respectively. Langmuir adsorption isotherm and pseudo-second order models could better explain the Cr(VI) and phenol adsorption behaviors over FeYBC. The Cr(VI) adsorption might be primarily achieved through the ion exchange and surface complexation and reduction, whereas the π-π interaction and electron donor-acceptor complex mainly contributed to phenol adsorption. The findings indicate that the biochar-based iron oxide composites material was an efficient adsorbent for the remediation of industrial effluents containing Cr(VI) and phenol.


Assuntos
Poluentes Químicos da Água , Água , Adsorção , Carvão Vegetal , Cromo , Compostos Férricos , Cinética , Fenol , Poluentes Químicos da Água/análise
2.
Molecules ; 26(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200734

RESUMO

A simple, rapid, accurate, and selective quantitative method based on 1H nuclear magnetic resonance (qNMR) was successfully established and developed for assessing the purity of dipotassium glycyrrhizinate (KG). In this study, using potassium hydrogen phthalate and fumaric acid as internal standard (IS), several important experimental parameters, such as relaxation delay and pulse angle, were explored. Reliability, specificity, linearity, limit of quantification, precision, stability, and accuracy were also validated. Calibration results obtained from qNMR were consistent with those obtained from HPLC coupled with ultraviolet detection. The proposed method, independent of the reference standard substance, is a useful, reliable, and practical protocol for the determination of KG and glycyrrhizin analogs.

3.
Zookeys ; 1042: 1-22, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34163286

RESUMO

The Oriental pselaphine genus Horniella Raffray, 1905 currently contains 29 species. In this paper, six new species are described: H. nantouensis Zhang, Hu & Yin, sp. nov. and H. taiwanensis Zhang, Hu & Yin, sp. nov. from Taiwan, China; H. bifurca Zhang & Yin, sp. nov. and H. haucki Zhang & Yin, sp. nov. from Thailand; H. khasiensis Zhang & Yin, sp. nov. from northern India; and H. sabahensis Zhang & Yin, sp. nov. from eastern Malaysia. In addition, H. aculeata Yin & Li, 2015, originally described from Yunnan, China, is newly recorded from Thailand.

4.
Zootaxa ; 4949(3): zootaxa.4949.3.11, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33903339

RESUMO

The genus Klimaszewskia Yin Zhang of the pselaphine tribe Tyrini was recently established to include a single species, viz., K. punctata Yin Zhang, from Indonesia (Yin Zhang 2021). However, the generic name was preoccupied by Klimaszewskia Szelegiewicz, 1979 (Hemiptera, Aphididae). In accordance with the International Code of Zoological Nomenclature (ICZN 1999: Article 60.3), a new replacement is here proposed.


Assuntos
Afídeos , Animais , Afídeos/classificação , Afídeos/fisiologia , Classificação
5.
Zootaxa ; 4938(2): zootaxa.4938.2.5, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33756981

RESUMO

Two new species of the genus Batrisodes Reitter, e.g., B. grandiceps sp. nov. and B. grossepunctatus sp. nov., are described from Shaanxi, central China. The two species are morphologically similar to each other in possessing similar cephalic modifications of the male, and the aedeagus with a well-developed endophallus.


Assuntos
Besouros , Distribuição Animal , Animais , China , Masculino
6.
Zootaxa ; 4942(4): zootaxa.4942.4.7, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33757052

RESUMO

A new genus and species of the pselaphine tribe Tyrini, Klimaszewskia punctata gen. et sp. nov., is described and illustrated from Java, Indonesia. Klimaszewskia gen. nov. differs from all other genera of Tyrini primarily by the long, extended maxillary palpus having the fourth palpomere that is mesally expanded near the base, and has an elongate and narrowed apical region, combined with the presence of an antebasal sulcus of the pronotum, and the long first visible tergite. A single female with much larger body size from Nepal, representing a second species of the new genus, is briefly characterized but left unnamed.


Assuntos
Besouros , Distribuição Animal , Animais , Tamanho Corporal , Feminino
7.
Comput Methods Biomech Biomed Engin ; 24(12): 1302-1309, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33586540

RESUMO

The cervical spine injury is a complicated procedure in the combination of different injury loads and postures. The aim of this study is to investigate the injury mechanism considering different types of cervical curvatures subjected to contusion loads. A finite element model of a cervical spinal cord was constructed. Gray matter, white matter and pia matter were modeled and hyperelastic material properties were assigned. Convergence analysis and validation analysis were carried out. The model was simulated in 3 different spinal curvatures and loaded by 2 directions with 4 compression degrees. The maximum von Mises stress in the whole model was concentrated in the pia matter in all loading cases. When investigating spinal cord injury, the pia matter must be considered. For all three curvatures, the stress in the gray matter and white matter was higher in front-to-back loading condition than that in back-to-front loading condition. The front-to-back impact may cause a larger damage. A back-to-front load damaged the structure around the central canal and a front-to-back contusion load damaged the anterior horn of the spinal cord at most time. From the view of the maximum stress, the lordotic curvature did not show significant buffering effect. However, the pathological curvature had large areas affected and the lordotic curvature showed some benefits to some degree from the view of stress distribution.


Assuntos
Medula Cervical , Contusões , Traumatismos da Medula Espinal , Vértebras Cervicais , Análise de Elementos Finitos , Humanos , Medula Espinal
8.
Neurotox Res ; 39(3): 720-739, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32955723

RESUMO

The activation of microglia is a hallmark of neuroinflammation and contributes to various neurodegenerative diseases. Chronic inorganic arsenic exposure is associated with impaired cognitive ability and increased risk of neurodegeneration. The present study aimed to investigate whether chronic inorganic arsenic-induced learning and memory impairment was associated with microglial activation, and how organic (DMAV 600 µM, MMAV 0.1 µM) and inorganic arsenic (NaAsO2 0.6 µM) affect the microglia. Male C57BL/6J mice were divided into two groups: a control group and a group exposed to arsenic in their drinking water (50 mg/L NaAsO2 for 24 weeks). The Morris water maze was performed to analyze neuro-behavior and transmission electron microscopy was used to assess alterations in cellular ultra-structures. Hematoxylin-eosin and Nissl staining were used to observe pathological changes in the cerebral cortex and hippocampus. Flow cytometry was used to reveal the polarization of the arsenic-treated microglia phenotype and GC-MS was used to assess metabolomic differences in the in vitro microglia BV-2 cell line model derived from mice. The results showed learning and memory impairments and activation of microglia in the cerebral cortex and dentate gyrus (DG) zone of the hippocampus, in mice chronically exposed to arsenic. Flow cytometry demonstrated that BV-2 cells were activated with the treatment of different arsenic species. The GC-MS data showed three important metabolites to be at different levels according to the different arsenic species used to treat the microglia. These included tyrosine, arachidonic acid, and citric acid. Metabolite pathway analysis showed that a metabolic pathways associated with tyrosine metabolism, the dopaminergic synapse, Parkinson's disease, and the citrate cycle were differentially affected when comparing exposure to organic arsenic and inorganic arsenic. Organic arsenic MMAV was predominantly pro-inflammatory, and inorganic arsenic exposure contributed to energy metabolism disruptions in BV-2 microglia. Our findings provide novel insight into understanding the neurotoxicity mechanisms of chronic arsenic exposure and reveal the changes of the metabolome in response to exposure to different arsenic species in the microglia.

9.
J Environ Manage ; 278(Pt 1): 111518, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33113397

RESUMO

Nowadays, nanoscale zero valent iron (nZVI) has been extensively applied for the decontamination of various pollutants, but passivation of nZVI severely affects its reactivity in use. In this study, ultrasound (US)-assisted catalytic reduction of Cr(VI) by an acid mine drainage based nZVI (AMD-nZVI) coupling with FeS2 system was systematically examined. Results show that the presence of FeS2 and US induced a synergistic enhancement of Cr(VI) removal by AMD-nZVI. Nearly 98% of Cr(VI) removal was achieved by AMD-nZVI/FeS2/US process within 60 min under optimal reaction conditions. Several coexisting substances with lower concentration including Pb(II), Ni(II), bisphenol A (BPA) and 2,4-diclorophenol (2,4-DCP) could be effectively removed in simultaneous manner with Cr(VI) removal. The inhibitory order of water matrix species on Cr(VI) removal was NO3- > PO43- > HCO3- > Ca2+ > Mg2+ > Cl-, and a serious suppression effect was induced by humic acid (HA). Addition of ethylene diamine tetra-acetic acid (EDTA) and citric acid (CA) could enhance Cr(VI) removal rate. An enhanced reaction mechanism was proposed, which involved the regeneration of more Fe2+ and H+ by AMD-nZVI/FeS2/US process, leading to the reduction of Cr(VI) by AMD-nZVI and FeS2 into Cr(III) species inculding Cr2O3 and Cr(OH)3. This study well demonstrates that AMD-nZVI/FeS2/US process is considered as a potential candidate for the remediation of Cr(VI) in real wasterwater.


Assuntos
Ferro , Poluentes Químicos da Água , Ácidos , Adsorção , Cromo/análise , Água , Poluentes Químicos da Água/análise
10.
Carbohydr Res ; 495: 108088, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32807356

RESUMO

We report the preparation of multivalent amide-sialoside-decorated human serum albumin (HSA) and bovine serum albumin (BSA) as mimics of natural mucin and bioshields against influenza virus infection. Free sialic acid with an amine on C-2 was covalently attached to the protein scaffolds using di-(N-succinimidyl) adipate. Dynamic light scattering (DLS) showed that the synthetic neomucins were able to act as bioshields and aggregate the influenza virion particles. The dissociation constants (KD) of the interactions between the prepared glycoconjugates and three different viral strains were measured by isothermal titration calorimetry (ITC) indicating the multivalent presentation of sialyl ligands on the HSA and BSA backbones can dramatically enhance the adsorbent capability compared to the corresponding monomeric sialoside. Hemagglutinin inhibition (HAI) and neuraminidase inhibition (NAI) assays showed that the glycoconjugates acted as moderate HA and NA inhibitors, thus impeding viral infection. Moreover, the different binding affinities of the glycoproteins to HA and NA proteins from different influenza viruses demonstrated the importance of HA/NA balance in viral replication and evolution. These findings provide a foundation for the development of antiviral drugs and viral adsorbent materials based on mimicking the structure of mucin.


Assuntos
Antivirais/farmacologia , Glicerol/farmacologia , Influenza Humana/prevenção & controle , Mucinas/metabolismo , Orthomyxoviridae/efeitos dos fármacos , Estearatos/farmacologia , Amidas/química , Amidas/farmacologia , Animais , Antivirais/química , Bovinos , Combinação de Medicamentos , Glicerol/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Estrutura Molecular , Mucinas/química , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Soroalbumina Bovina/metabolismo , Albumina Sérica Humana/metabolismo , Ácidos Siálicos/química , Ácidos Siálicos/farmacologia , Estearatos/química
13.
Nat Commun ; 10(1): 1981, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-31040273

RESUMO

Cardiovascular and metabolic disease (CMD) remains a main cause of premature death worldwide. Berberine (BBR), a lipid-lowering botanic compound with diversified potency against metabolic disorders, is a promising candidate for ameliorating CMD. The liver is the target of BBR so that liver-site accumulation could be important for fulfilling its therapeutic effect. In this study a rational designed micelle (CTA-Mic) consisting of α-tocopheryl hydrophobic core and on-site detachable polyethylene glycol-thiol shell is developed for effective liver deposition of BBR. The bio-distribution analysis proves that the accumulation of BBR in liver is increased by 248.8% assisted by micelles. Up-regulation of a range of energy-related genes is detectable in the HepG2 cells and in vivo. In the high fat diet-fed mice, BBR-CTA-Mic intervention remarkably improves metabolic profiles and reduces the formation of aortic arch plaque. Our results provide proof-of-concept for a liver-targeting strategy to ameliorate CMD using natural medicines facilitated by Nano-technology.


Assuntos
Berberina/farmacologia , Hipoglicemiantes/uso terapêutico , Nanotecnologia/métodos , Animais , Células CACO-2 , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/tratamento farmacológico , Dislipidemias/sangue , Dislipidemias/tratamento farmacológico , Células Hep G2 , Humanos , Hipoglicemiantes/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Doenças Metabólicas/sangue , Doenças Metabólicas/tratamento farmacológico , Camundongos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
J Asian Nat Prod Res ; 21(9): 928-938, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31111726

RESUMO

This study investigated the therapeutic effects of a water-soluble biphenyl compound, WLP-S-14, in acute-on-chronic liver failure (ACLF). Wistar rats were injected intraperitoneally with porcine serum twice a week for 8 weeks prior to administration of 600 mg/kg D-galactosamine and 50 µg/kg lipopolysaccharide to induce ACLF. Study groups were treated intravenously with saline or with 100 or 200 mg/kg WLP-S-14. WLP-S-14 ameliorated ACLF with significant reductions in the mortality rate and transaminase levels, indicating improved liver function. The mechanism underlying these effects may involve decreased levels of tumor necrosis factor-α and interleukin-6, with associated inhibition of apoptotic pathways.


Assuntos
Compostos de Bifenilo/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Animais , Compostos de Bifenilo/química , Galactosamina/toxicidade , Lipopolissacarídeos/toxicidade , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Estrutura Molecular , Distribuição Aleatória , Ratos , Ratos Wistar , Soro
15.
Life Sci ; 217: 8-15, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30500551

RESUMO

AIMS: The apoptosis and autophagy play an important role in the pathogenesis of sepsis-induced cardiac dysfunction. Previous studies have demonstrated that melatonin protects against cardiac dysfunction during sepsis. In addition, silent information regulator 1 (SIRT1) is a therapeutic target for sepsis-induced myocardial dysfunction. The aims of this study were to investigate whether SIRT1 was involved in melatonin's cardioprotection during sepsis and the mechanisms. MATERIALS AND METHODS: In this study, twenty-four male C57BL/6 mice were randomly assigned to four groups: Control group, LPS group, LPS + Melatonin group and LPS + Melatonin + EX527 group. Mice were treated with lipopolysaccharide for 8 h with or without melatonin or EX527. The cardiac function, myocardial injury biomarkers, cardiac histopathology, cardiomyocyte apoptosis, autophagosome as well as the protein expressions of SIRT1, cleaved caspase-3, LC3-II/LC3-I ratio and p62 in the myocardium were assayed. KEY FINDINGS: The results demonstrated that melatonin significantly improved cardiac function, decreased creatine kinase (CK) and creatine kinase-MB (CK-MB) levels, attenuated myocardial architecture destruction, inhibited cardiomyocyte apoptosis and increased cardiac autophagy as compared with the LPS group. In addition, melatonin significantly increased SIRT1 protein expression in the myocardium of mice with sepsis, while inhibition of SIRT1 by EX527 abolished melatonin's cardioprotection during sepsis. SIGNIFICANCE: In this study, we found that melatonin protected against sepsis-induced cardiac dysfunction by regulating apoptosis and autophagy via activation of SIRT1 in mice.


Assuntos
Apoptose/efeitos dos fármacos , Cardiotônicos/uso terapêutico , Cardiopatias/etiologia , Cardiopatias/prevenção & controle , Melatonina/uso terapêutico , Sepse/complicações , Sirtuína 1/metabolismo , Animais , Autofagia/efeitos dos fármacos , Coração/efeitos dos fármacos , Coração/fisiopatologia , Cardiopatias/metabolismo , Cardiopatias/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia , Sepse/metabolismo , Sepse/fisiopatologia , Sirtuína 1/análise
16.
Biomaterials ; 141: 13-28, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28666099

RESUMO

Small active RNA (saRNA)-induced gene activation (RNAa) is a novel strategy to treat cancer. Our previous work proved that the p21-saRNA-322 successfully hindered colorectal cancer growth by activating p21 gene. However, the barrier for successful saRNA therapy is lack of efficient drug delivery. In the present study, a rectal delivery system entitled p21-saRNA-322 encapsulated tumor-selective lipopolyplex (TSLPP-p21-saRNA-322) which consist of PEI/p21-saRNA-322 polyplex core and hyaluronan (HA) modulated lipid shell was developed to treat colorectal cancer. Our results showed that this system maintained at the rectum for more than 6 h and preferentially accumulated at tumor site. CD44 knock down experiment instructed that the superb cellular uptake of TSLPP-p21-saRNA-322 attributed to HA-CD44 recognition. An orthotopic model of bio-luminescence human colorectal cancer in mice was developed using microsurgery and TSLPP-p21-saRNA-322 demonstrated a superior antitumor efficacy in vitro and in vivo. Our results provide preclinical proof-of-concept for a novel method to treat colorectal cancer by rectal administration of TSLPP formulated p21-saRNA-322.


Assuntos
Neoplasias Colorretais/terapia , Inibidor de Quinase Dependente de Ciclina p21/genética , Técnicas de Transferência de Genes , Terapia Genética/métodos , RNA/uso terapêutico , Ativação Transcricional , Animais , Ciclo Celular , Colo/metabolismo , Colo/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Sistemas de Liberação de Medicamentos/métodos , Células HT29 , Humanos , Receptores de Hialuronatos/genética , Ácido Hialurônico/análogos & derivados , Lipídeos/química , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , RNA/administração & dosagem , RNA/genética , Reto/metabolismo , Reto/patologia
17.
Molecules ; 22(7)2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28671639

RESUMO

We have developed a new method to prepare 4-acetoxy substituted 5(4H)-oxazolones by direct oxidation of N-benzoyl amino-acids using hypervalent iodine. The method is efficient, economical and easy to perform for the synthesis of quaternary substituted amino acid derivatives. We used online FTIR monitoring techniques to analyze the reaction, and gave a plausible reaction mechanism.


Assuntos
Aminoácidos/química , Iodo/química , Oxazolona/química , Catálise , Estrutura Molecular , Oxirredução
18.
Molecules ; 21(1): E8, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26729072

RESUMO

Seven metabolites of 2',3',5'-tri-O-acetyl-N6-(3-hydroxyphenyl) adenosine (WS070117) were synthesized by deacetylation, hydrolysis, cyclization, sulfonylation and glycosylation reactions, respectively. All these compounds, which could be useful as material standards for metabolic research, were characterized by NMR and HPLC-MS (ESI) analyses.


Assuntos
Adenosina/análogos & derivados , Adenosina/química , Ciclização , Glicosilação , Hidrólise , Estrutura Molecular
19.
Neurosci Lett ; 560: 81-5, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24370596

RESUMO

Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases are the main enzymes that produce oxidative stress, which plays an important role in painful diabetic neuropathy. Curcumin has been reported to exert an antinociceptive effect in a rat model of diabetic neuropathy by suppressing oxidative stress in the spinal cord. However, it remains unknown whether the mechanism by which curcumin ameliorates diabetic neuropathy can be attributed to spinal NADPH oxidases. This study was designed to determine the effect of curcumin on diabetic neuropathy and to investigate its precise mechanism in relation to NADPH oxidase-mediating oxidative stress in the spinal cord. Diabetic neuropathy was induced in Sprague-Dawley rats by intraperitoneal injection with 1% streptozotocin (STZ; 60 mg/kg). After the onset of diabetic neuropathy, a subset of the diabetic rats received daily intragastric administrations of curcumin (200mg/kg) or intraperitoneal injections of apocynin (2.5mg/kg) for 14 consecutive days, whereas other diabetic rats received equivalent volumes of normal saline (NS). STZ resulted in diabetic neuropathy with hyperglycemia and a lower paw withdrawal threshold (PWT), accompanied by elevations in the expression of the NADPH oxidase subunits p47(phox) and gp91(phox) and in the levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA) and a reduction in superoxide dismutase (SOD) activity (P<0.05) in the spinal cord. Both curcumin and apocynin ameliorated diabetic neuropathy. In conclusion, curcumin attenuated neuropathic pain in diabetic rats, at least partly by inhibiting NADPH oxidase-mediating oxidative stress in the spinal cord.


Assuntos
Antioxidantes/farmacologia , Curcumina/farmacologia , Neuropatias Diabéticas/tratamento farmacológico , NADPH Oxidases/antagonistas & inibidores , Estresse Oxidativo/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Acetofenonas/farmacologia , Animais , Antioxidantes/uso terapêutico , Peso Corporal/efeitos dos fármacos , Curcumina/uso terapêutico , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/fisiopatologia , Peróxido de Hidrogênio/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/fisiopatologia , Masculino , Malondialdeído/metabolismo , NADPH Oxidases/metabolismo , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Estreptozocina , Superóxido Dismutase/metabolismo
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