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1.
Sci Rep ; 14(1): 10642, 2024 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724565

RESUMO

Colorectal cancer (CRC) often necessitates cetuximab (an EGFR-targeting monoclonal antibody) for treatment. Despite its clinical utility, the specific operative mechanism of cetuximab remains elusive. This research investigated the influence of PLCB3, a potential CRC oncogene, on cetuximab treatment. We extracted differentially expressed genes from the GSE140973, the overlapping genes combined with 151 Wnt/ß-Catenin signaling pathway-related genes were identified. Then, we conducted bioinformatics analysis to pinpoint the hub gene. Subsequently, we investigated the clinical expression characteristics of this hub gene, through cell experimental, scrutinized the impact of cetuximab and PLCB3 on CRC cellular progression. The study identified 26 overlapping genes. High expression of PLCB3, correlated with poorer prognosis. PLCB3 emerged as a significant oncogene associated with patient prognosis. In vitro tests revealed that cetuximab exerted a cytotoxic effect on CRC cells, with PLCB3 knockdown inhibiting CRC cell progression. Furthermore, cetuximab treatment led to a reduction in both ß-catenin and PLCB3 expression, while simultaneously augmenting E-cadherin expression. These findings revealed PLCB3 promoted cetuximab inhibition on Wnt/ß-catenin signaling. Finally, simultaneous application of cetuximab with a Wnt activator (IM12) and PLCB3 demonstrated inhibited CRC proliferation, migration, and invasion. The study emphasized the pivotal role of PLCB3 in CRC and its potential to enhance the efficacy of cetuximab treatment. Furthermore, cetuximab suppressed Wnt/ß-catenin pathway to modulate PLCB3 expression, thus inhibiting colorectal cancer progression. This study offered fresh perspectives on cetuximab mechanism in CRC.


Assuntos
Proliferação de Células , Cetuximab , Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , Via de Sinalização Wnt , beta Catenina , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Cetuximab/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , beta Catenina/metabolismo , beta Catenina/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Prognóstico , Antineoplásicos Imunológicos/farmacologia
2.
J Ethnopharmacol ; 330: 118234, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38670404

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hai-Honghua medicinal liquor (HHML), an external Chinese herbal formula preparation, is often applied to treat freshly closed tibia/fibular fractures, ankle fractures, and other bone-related disorders, but the related molecular mechanism is unclear. AIM OF THE STUDY: To evaluate the therapeutic effect of HHML in patients with tibial/fibular and ankle fractures, and to explore its related possible mechanism. METHODS AND MATERIALS: A total of 182 patients with tibia/fibular fractures and 183 patients with ankle fractures were enrolled in this study. A randomized, controlled, unblinded clinical trial was designed to evaluate the therapeutic effect of HHML on tibial/fibular and ankle fractures. The chemical compositions of HHML were analyzed by the HPLC-Q-Extractive MS/MS. Furthermore, a rat tibial fracture model was established to evaluate the therapeutic effects of HHML in promoting fracture healing, and the mouse embryonic osteoblasts cell line of MC3T3-E1 was further carried out to explore the mechanisms of HHML on osteoblast differentiation. RESULTS: In the clinical evaluation, HHML treatment significantly shortened the time for pain and swelling in patients with tibial/fibular fractures (P < 0.01) and ankle fractures (P < 0.01), and the incidence of complications was significantly reduced as well. Subsequently, 116 constituents were identified from HHML via HPLC-Q-TOF-MS/MS analysis. In vivo, no obvious changes in weight were observed in HHML-treated rats. Moreover, the levels of bone formation markers (including osteocalcin (OCN), N-terminal propeptide of type I procollagen (PINP), alkaline phosphatase (ALP), calcium (Ca) and substance P) in rat serum were significantly increased in HHML-treated rats compared with model rats (P < 0.05). Micro-CT analysis showed bone mineral density (BMD), bone volume fraction (BV/TV), trabecular thickness (Tb.Th) of the HHML-treated rats were significantly increased (P < 0.05, vs. Model) while trabecular separation (Tb.Sp) and structure model index (SMI) values were significantly reduced (P < 0.05, vs. Model). Histological analysis showed that HHML treatment promoted the healing of fractures and cartilage repair, and increased the osteoblasts and collagen fibers. Furthermore, our results also revealed HHML could promote MC3T3-E1 cells proliferation and osteoblast differentiation via regulation of the runt-related transcription factor 2 (RUNX2), bone alkaline phosphatase (BALP), and OCN by activating phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) pathway, which confirmed by adding PI3K chemical inhibitor of LY294002. CONCLUSION: HHML treatment is a reliable remedy for fractures in tibial and ankle by promotion of osteogenic differentiation via activation of PI3K/Akt pathway.


Assuntos
Diferenciação Celular , Medicamentos de Ervas Chinesas , Osteoblastos , Osteogênese , Proteínas Proto-Oncogênicas c-akt , Ratos Sprague-Dawley , Animais , Medicamentos de Ervas Chinesas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Masculino , Osteogênese/efeitos dos fármacos , Humanos , Camundongos , Diferenciação Celular/efeitos dos fármacos , Feminino , Pessoa de Meia-Idade , Adulto , Ratos , Osteoblastos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Consolidação da Fratura/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fraturas Ósseas/tratamento farmacológico , Idoso , Adulto Jovem , Modelos Animais de Doenças
3.
Phytomedicine ; 121: 155113, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37748388

RESUMO

BACKGROUND: Accumulating evidence suggested increasing energy expenditure is a feasible strategy for combating obesity, and browning of white adipose tissue (WAT) to promote thermogenesis might be one of the attractive ways. Hydroxy-α-sanshool (HAS), a natural amide alkaloid extracted from the fruits of Zanthoxylum bungeanum Maxim, possesses lots of benefits in lipid metabolism regulation. METHODS: The anti-obesity effect of HAS was investigated by establishing an animal model of obesity and a 3T3-L1 differentiation cell model. Effects of HAS on the whole-body fat and liver of obese mice, and the role of HAS in inducing browning of white fat were studied by Micro CT, Metabolic cage detection, Cell mitochondrial pressure detection, transmission electron microscopy and cold exposure assays. Furthermore, the Real-time PCR (qPCR), digital PCR (dPCR), western blot, Co-immunoprecipitation (Co-IP), molecular docking, drug affinity responsive target stability (DARTS), Cellular thermal shift assay (CETSA) and other methods were used to investigate the target and mechanisms of HAS. RESULTS: We found that treatment with HAS helped mice combat obesity caused by a high fat diet (HFD) and improve metabolic characteristics. In addition, our results suggested that the anti-obesity effect of HAS is related to increase energy consumption and thermogenesis via induction of browning of WAT. The further investigations uncovered that HAS can up-regulate UCP-1 expression, increase mitochondria number, and elevate the cellular oxygen consumption rates (OCRs) of white adipocytes. Importantly, the results indicated that browning effects of HAS is closely associated with SIRT1-dependent PPAR-γ deacetylation through activating the TRPV1/AMPK pathway, and TRPV1 is the potential drug target of HAS for the browning effects of WAT. CONCLUSIONS: Our results suggested the HAS can promote browning of WAT via regulating AMPK/SIRT-1/PPARγ signaling, and the potential drug target of HAS is the membrane receptor of TRPV1.


Assuntos
PPAR gama , Zanthoxylum , Camundongos , Animais , PPAR gama/metabolismo , Frutas , Simulação de Acoplamento Molecular , Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo Branco , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Alcamidas Poli-Insaturadas/farmacologia , Dieta Hiperlipídica/efeitos adversos , Células 3T3-L1 , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/farmacologia
4.
Cell Cycle ; 22(17): 1807-1826, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37587724

RESUMO

Background: Cancer-associated fibroblast (CAF) exosomal miRNAs have gradually a hot spot in cancer therapy. This study mainly explores the effect of CAF-derived exosomal miR-29b-1-5p on gastric cancer (GC) cells.Methods: CAFs and exosomes were identified by Western blot and transmission electron microscopy. CAF-derived exosomes-GC cells co-culture systems were constructed. Effects of CAF-derived exosomal miR-29b-1-5p on GC cells were determined by cell counting kit-8, flow cytometry, wound healing, Transwell assays and Western blot. The relationship between miR-29b-1-5p and immunoglobulin domain-containing 1 (VSIG1) was assessed by TargetScan, dual-luciferase reporter and RNA immunoprecipitation (RIP) experiments. The interaction between VSIG1 and zonula occluden-1 (ZO-1) was detected by co-immunoprecipitation. Expressions of miR-29b-1-5p, VSIG1 and ZO-1 were determined by quantitative real-time PCR. Vascular mimicry (VM) was detected using immunohistochemistry and tube formation assays. Rescue experiments and xenograft tumor assays were used to further determine the effect of CAF-derived exosomal miR-29b-1-5p/VSIG1 on GC.Results: VM structure, upregulation of miR-29b-1-5p, and downregulation of VSIG1 and ZO-1 were shown in GC tissues. MiR-29b-1-5p targeted VSIG1, which interacted with ZO-1. CAF-derived exosomal miR-29b-1-5p inhibitor suppressed the viability, migration, invasion and VM formation, but promoted the apoptosis of GC cells. MiR-29b-1-5p inhibitor increased levels of VSIG1, ZO-1 and E-cadherin, whilst decreasing levels of VE-cadherin, N-cadherin and Vimentin in vitro and in vivo, which however was partially reversed by shVSIG1. Downregulation of CAF-derived exosomal miR-29b-1-5p impeded GC tumorigenesis and VM structure in vivo by upregulating VSIG1/ZO-1 expression.Conclusion: Downregulation of CAF-derived exosomal miR-29b-1-5p inhibits GC progression via VSIG1/ZO-1 axis.


Assuntos
Fibroblastos Associados a Câncer , Exossomos , MicroRNAs , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Junções Íntimas , Regulação para Baixo/genética , Apoptose/genética , MicroRNAs/genética , Domínios de Imunoglobulina , Proliferação de Células , Linhagem Celular Tumoral
5.
Inorg Chem ; 62(1): 401-407, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36537348

RESUMO

The first mixed-valence nanocluster CuI/CuII with the highest percentage of CuII ions was synthesized by using 4-tert-butylcalix[4]arene (Calix4), with the formula DMF2⊂[(CO3)2-@CuII6CuI3(Calix4)3Cl2(DMF)5(H3O)]•DMF (1), as a photothermal nanocluster. Its structure was characterized using single-crystal X-ray diffraction, Fourier-transform infrared spectroscopy, and powder X-ray diffraction. In addition, the charge state and chemical composition of the nanocluster were determined using electrospray ionization spectrometry and X-ray photoelectron spectroscopy (XPS) spectrum. The results of the XPS and X-ray crystallography revealed that there are two independent CuII and CuI centers in nanocluster 1 with the relative abundances of 66.6 and 33.3% for CuII and CuI, respectively. The nanocluster contains three four-coordinated CuI ions with a square-planar geometry and six five-coordinated CuII ions with a square pyramid geometry. The nanocluster shows strong near-infrared optical absorption in the solid state and excellent photothermal conversion ability (the equilibrium temperature ∼78.2 °C) with the light absorption centers in 286-917 nm over previous reported pentanucleus CuI4CuII clusters and CuII compounds.

6.
Front Pharmacol ; 13: 1089558, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36582530

RESUMO

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease characterized by hyperglycemia. The fruits of Zanthoxylum bungeanum Maxim. is a common spice and herbal medicine in China, and hydroxy-α-sanshool (HAS) is the most abundant amide in Z. bungeanum and reported to have significant hypoglycemic effects. The purpose of this study was to evaluate the ameliorative effects of HAS on T2DM and the potential mechanisms responsible for those effects. An acute toxicity test revealed the median lethal dose (LD50) of HAS is 73 mg/kg. C57BL/6 J mice were fed a high-fat diet and given an intraperitoneal injection of streptozotocin (STZ) to induce T2DM in mice to evaluate the hypoglycemic effects of HAS. The results showed that HAS significantly reduced fasting blood glucose, reduced pathological changes in the liver and pancreas, and increased liver glycogen content. In addition, glucosamine (GlcN)-induced HepG2 cells were used to establish an insulin resistance cell model and explore the molecular mechanisms of HAS activity. The results demonstrated that HAS significantly increases glucose uptake and glycogen synthesis in HepG2 cells and activates the PI3K/Akt pathway in GlcN-induced cells, as well as increases GSK-3ß phosphorylation, suppresses phosphorylation of glycogen synthase (GS) and increases glycogen synthesis in liver cells. Furthermore, these effects of HAS were blocked by the PI3K inhibitor LY294002. The results of our study suggest that HAS reduces hepatic insulin resistance and increases hepatic glycogen synthesis by activating the PI3K/Akt/GSK-3ß/GS signaling pathway.

7.
Inorg Chem ; 61(42): 16693-16698, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36239444

RESUMO

The synthesis of nanoclusters from simple structural units is usually a challenging process because of the complexity and unpredictability of the self-assembly process of these types of compounds. Herein, two new neutral 19-nuclearity silver nanoclusters based on alkynyl ligands with the formulas [(CrO4)@Ag19(C≡CtBu)8(Ph2PO2)6(tfa)3(CH3OH)2] (1) and [(SO4)@Ag19(C≡CtBu)8(Ph2PO2)6(tfa)3(CH3OH)2] (2), in which tfa = trifluoroacetate, were synthesized, and their structures were investigated by single-crystal and powder X-ray diffraction, electrospray ionization mass spectrometry, elemental analyses, and Fourier transform infrared spectroscopy. The surface ligands of Ph2PO2H and trifluoroacetate were assembled through hydrogen bonding, metal-aromatic interactions, and coordination bonding around 19 silver atoms as the metal skeletons of the nanoclusters. Sulfate and chromate anions, as a template within the metal skeleton of clusters through bonding with silver atoms, stabilized the structure. In addition, the UV-vis absorption spectroscopy, luminescence properties, and thermal stability of the nanoclusters were investigated.

8.
Nanoscale ; 14(29): 10321-10326, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35818748

RESUMO

Two superatomic solids, a bi-cluster compound, [Ag6(3S)4(OTf)4][Ag6(3S)4(CCtBu)4](OTf)2 [Ag6(0)·Ag6(i)], and a homologous nanocluster, [Ag6(3S)4(tfa)4] (Ag6), have been described here, which are both close-packed in the crystal lattice with the ligation of trithiane. Their aggregation-state-dependent absorption and fluorescence properties could be ascribed to the enhanced intercluster charge-transfer in the crystalline state.

9.
Dalton Trans ; 51(15): 6053-6060, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35353105

RESUMO

To enhance light absorption in the visible region for the utilization of sunlight, eight mixed-valence polynuclear CuI/CuII clusters have been synthesized for evaluating their photothermal conversion performance. They are fabricated considering the ligand's electron density distribution inhomogeneity using 1,2,3-triazole (3N) or tetrazole (4N) and different mono-phosphine ligands. We report here the synthesis, crystal structure, characterization, optical properties, and photothermal conversion performance of these clusters. X-ray crystal structures reveal that those pentanuclear clusters are neutral clusters with octahedrally-coordinated copper(II) ion being surrounded by four tetrahedrally coordinated copper(I) ions. Interestingly, with the introduction of the mixed-valence centers, these compounds show additional light absorption centers in 350-600 nm via the IVCT transition mechanism, compared with our previously reported Cu(II) compounds. These clusters show excellent photothermal conversion performance, with an average equilibrium temperature (∼60 °C) and a temperature increment (∼40 °C), which are also superior to Cu(II) complexes (the average equilibrium temperature ∼55 °C). This work proves that it is possible to design and prepare new polynuclear mixed-valence CuI/CuII clusters for achieving high-performance photothermal conversion materials.

10.
J Healthc Eng ; 2021: 9174055, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707800

RESUMO

BACKGROUND: Breast cancer (BRCA) is one of the most common cancers and the leading cause of cancer-related death in women. RNA-binding proteins (RBPs) play an important role in the emergence and pathogenesis of tumors. The target RNAs of RBPs are very diverse; in addition to binding to mRNA, RBPs also bind to noncoding RNA. Noncoding RNA can cause secondary structures that can bind to RBPs and regulate multiple processes such as splicing, RNA modification, protein localization, and chromosomes remodeling, which can lead to tumor initiation, progression, and invasion. METHODS: (1) BRCA data were downloaded from The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC) databases and were used as training and testing datasets, respectively. (2) The prognostic RBPs-related genes were screened according to the overlapping differentially expressed genes (DEGs) from the TCGA database. (3) Univariate Cox proportional hazard regression was performed to identify the genes with significant prognostic value. (4) Further, we used the LASSO regression to construct a prognostic signature and validated the signature in the TCGA and ICGC cohort. (5) Besides, we also performed prognostic analysis, expression level verification, immune cell correlation analysis, and drug correlation analysis of the genes in the model. RESULTS: Four genes (MRPL13, IGF2BP1, BRCA1, and MAEL) were identified as prognostic gene signatures. The prognostic model has been validated in the TCGA and ICGC cohorts. The risk score calculated with four genes signatures could largely predict overall survival for 1, 3, and 5 years in patients with BRCA. The calibration plot demonstrated outstanding consistency between the prediction and actual observation. The findings of online database verification revealed that these four genes were significantly highly expressed in tumors. Also, we observed their significant correlations with some immune cells and also potential correlations with some drugs. CONCLUSION: We constructed a 4-RBPs-based prognostic signature to predict the prognosis of BRCA patients, and it has the potential for treating and diagnosing BRCA.


Assuntos
Neoplasias da Mama , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Feminino , Humanos , Prognóstico , RNA Mensageiro , Proteínas de Ligação a RNA/genética
11.
Chin J Traumatol ; 24(2): 88-93, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33526264

RESUMO

PURPOSE: This research examined road traffic injury mortality and morbidity disparities across of country development status, and discussed the possibility of reducing country disparities by various actions to accelerate the pace of achieving Sustainable Development Goals target 3.6 - to halve the number of global deaths and injuries from road traffic accidents by 2020. METHODS: Data for road traffic mortality, morbidity, and socio-demographic index (SDI) were extracted by country from the estimates of the Global Burden of Disease study, and the implementation of the three types of national actions (legislation, prioritized vehicle safety standards, and trauma-related post-crash care service) were extracted from the Global Status Report on Road Safety by World Health Organization. We fitted joinpoint regression analysis to identify and quantify the significant rate changes from 2011 to 2017. RESULTS: Age-adjusted road traffic mortality decreased substantially for all the five SDI categories from 2011 to 2017 (by 7.52%-16.08%). Age-adjusted road traffic mortality decreased significantly as SDI increased in the study time period, while age-adjusted morbidity generally increased as SDI increased. Subgroup analysis by road user yielded similar results, but with two major differences during the study period of 2011 to 2017: (1) pedestrians in the high SDI countries experienced the lowest mortality (1.68-1.90 per 100,000 population) and morbidity (110.45-112.72 per 100,000 population for incidence and 487.48-491.24 per 100,000 population for prevalence), and (2) motor vehicle occupants in the high SDI countries had the lowest mortality (4.07-4.50 per 100,000 population) but the highest morbidity (428.74-467.78 per 100,000 population for incidence and 1025.70-1116.60 per 100,000 population for prevalence). Implementation of the three types of national actions remained nearly unchanged in all five SDI categories from 2011 to 2017 and was consistently stronger in the higher SDI countries than in the lower SDI countries. Lower income nations comprise the heaviest burden of global road traffic injuries and deaths. CONCLUSION: Global road traffic deaths would decrease substantially if the large mortality disparities across country development status were reduced through full implementation of proven national actions including legislation and law enforcement, prioritized vehicle safety standards and trauma-related post-crash care services.


Assuntos
Lesões Acidentais/epidemiologia , Lesões Acidentais/mortalidade , Acidentes de Trânsito/estatística & dados numéricos , Países em Desenvolvimento/estatística & dados numéricos , Pedestres/estatística & dados numéricos , Desenvolvimento Sustentável , Lesões Acidentais/prevenção & controle , Acidentes de Trânsito/legislação & jurisprudência , Acidentes de Trânsito/prevenção & controle , Humanos , Incidência , Renda/estatística & dados numéricos , Morbidade , Prevalência , Fatores Socioeconômicos , Desenvolvimento Sustentável/tendências , Fatores de Tempo
12.
Parasit Vectors ; 13(1): 592, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33228764

RESUMO

BACKGROUND: Acanthamoeba spp. are free-living amoeba that are ubiquitously distributed in the environment. This study examines pathogenic Acanthamoeba cysteine proteases (AcCPs) belonging to the cathepsin L-family and explores the mechanism of AcCP3 interaction with host cells. METHODS: Six AcCP genes were amplified by polymerase chain reaction (PCR). Quantitative real-time PCR was used to analyse the relative mRNA expression of AcCPs during the encystation process and between pre- and post-reactivated trophozoites. To further verify the role of AcCP3 in these processes, AcCP3 recombinant proteins were expressed in Escherichia coli, and the hydrolytic activity of AcCP3 was determined. The influence of the AcCP3 on the hydrolytic activity of trophozoites and the toxicity of trophozoites to human corneal epithelial cells (HCECs) was examined by inhibiting AcCP3 expression using siRNA. Furthermore, the levels of p-Raf and p-Erk were examined in HCECs following coculture with AcCP3 gene knockdown trophozoites by Western blotting. RESULTS: During encystation, five out of six AcCPs exhibited decreased expression, and only AcCP6 was substantially up-regulated at the mRNA level, indicating that most AcCPs were not directly correlated to encystation. Furthermore, six AcCPs exhibited increased expression level following trophozoite reactivation with HEp-2 cells, particularly AcCP3, indicating that these AcCPs might be virulent factors. After refolding of recombinant AcCP3 protein, the 27 kDa mature protein from the 34 kDa pro-protein hydrolysed host haemoglobin, collagen and albumin and showed high activity in an acidic environment. After AcCP3 knockdown, the hydrolytic activity of trophozoite crude protein against gelatin was decreased, suggesting that these trophozoites had decreased toxicity. Compared with untreated trophozoites or negative control siRNA-treated trophozoites, AcCP3-knockdown trophozoites were less able to penetrate and damage monolayers of HCECs. Western blot analysis showed that the activation levels of the Ras/Raf/Erk/p53 signalling pathways in HCECs decreased after inhibiting the expression of trophozoite AcCP3. CONCLUSIONS: AcCP6 was correlated to encystation. Furthermore, AcCP3 was a virulent factor in trophozoites and participated in the activation of the Ras/Raf/Erk/p53 signalling pathways of host cells.


Assuntos
Acanthamoeba castellanii/enzimologia , Acanthamoeba castellanii/genética , Acanthamoeba castellanii/patogenicidade , Cisteína Proteases/metabolismo , Catepsina L/genética , Cisteína Proteases/genética , Expressão Gênica , Células HeLa , Interações Hospedeiro-Parasita , Humanos , Encistamento de Parasitas , Proteínas de Protozoários/genética , Proteínas Recombinantes/genética , Alinhamento de Sequência , Trofozoítos/química , Trofozoítos/genética , Trofozoítos/metabolismo
13.
Materials (Basel) ; 13(7)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230850

RESUMO

This paper reports the improvement of microstructural and hardness properties of 3 mol% yttria-stabilized zirconia (3Y-TZP) ceramics with nano TiO2 powders (with 0, 0.9, 1.8, and 2.7 wt%) added using a low-temperature microwave-assisted sintering of 1250 °C. Even at such a low sintering temperature, all sintered samples had the main phase of tetragonal zirconia (t-ZrO2) without the appearance of the secondary monoclinic phase or TiO2 phase, and had high relative densities, larger than 95%. The grain growth was well developed, and the grain sizes were around 300-600 nm. The Ti and O elements appeared at the grain and grain boundary and increased with the increased nano TiO2 contents identified by the element analysis, although the TiO2 phase did not appear in the X-ray pattern. The Vickers hardness was in the range of 10.5 to 14.5 GPa, which first increased with increasing content till 0.9 wt% and then decreased. With citric acid corrosion treatment for 10 h, the Vickers hardness only decreased from 14.34 GPa to 13.55 GPa with the addition of 0.9 wt% nano TiO2 powder. The experiment results showed that 0.9 wt% nano TiO2 addition can improve the densification as well as the Vickers hardness under a low temperature of microwave-assisted sintering.

14.
Nano Lett ; 20(1): 272-277, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31821008

RESUMO

While various effects of physicochemical parameters (e.g., size, facet, composition, and internal structure) on the catalytic efficiency of nanozymes (i.e., nanoscale enzyme mimics) have been studied, the strain effect has never been reported and understood before. Herein, we demonstrate the strain effect in nanozymes by using Pd octahedra and icosahedra with peroxidase-like activities as a model system. Strained Pd icosahedra were found to display 2-fold higher peroxidase-like catalytic efficiency than unstrained Pd octahedra. Theoretical analysis suggests that tensile strain is more beneficial to OH radical (a key intermediate for the catalysis) generation than compressive strain. Pd icosahedra are more active than Pd octahedra because icosahedra amplify the surface strain field. As a proof-of-concept demonstration, the strained Pd icosahedra were applied to an immunoassay of biomarkers, outperforming both unstrained Pd octahedra and natural peroxidases. The findings in this research may serve as a strong foundation to guide the design of high-performance nanozymes.


Assuntos
Nanoestruturas/química , Paládio/química , Peroxidases/química , Catálise , Oxirredução
15.
Sci Rep ; 9(1): 8616, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197195

RESUMO

In this work, a high thermoelectric figure of merit, zT of 1.9 at 740 K is achieved in Ge1-xBixTe crystals through the concurrent of Seebeck coefficient enhancement and thermal conductivity reduction with Bi dopants. The substitution of Bi for Ge not only compensates the superfluous hole carriers in pristine GeTe but also shifts the Fermi level (EF) to an eligible region. Experimentally, with moderate 6-10% Bi dopants, the carrier concentration is drastically decreased from 8.7 × 1020 cm-3 to 3-5 × 1020 cm-3 and the Seebeck coefficient is boosted three times to 75 µVK-1. In the meantime, based on the density functional theory (DFT) calculation, the Fermi level EF starts to intersect with the pudding mold band at L point, where the band effective mass is enhanced. The enhanced Seebeck coefficient effectively compensates the decrease of electrical conductivity and thus successfully maintain the power factor as large as or even superior than that of the pristine GeTe. In addition, the Bi doping significantly reduces both thermal conductivities of carriers and lattices to an extremely low limit of 1.57 W m-1K-1 at 740 K with 10% Bi dopants, which is an about 63% reduction as compared with that of pristine GeTe. The elevated figure of merit observed in Ge1-xBixTe specimens is therefore realized by synergistically optimizing the power factor and downgrading the thermal conductivity of alloying effect and lattice anharmonicity caused by Bi doping.

16.
J Cell Physiol ; 234(12): 22960-22971, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31127627

RESUMO

Osteoporosis is an ageing disease characterized by elevated osteoclastic bone resorption resulting in bone loss, decrease bone strength, and elevated incidence of fractures. Neferine, a natural compound isolated from the traditional Chinese medicine Nelumbo nucifera (Lotus), has been reported exhibit anti-inflammatory, antioxidant, and anticancer properties. However, its effect on bone remains to be determined. Here we showed that Neferine inhibits RANKL-induced osteoclast formation in a dose- and time-dependent manner. Furthermore, Neferine also demonstrated antiresorptive properties by effectively ameliorating the bone resorptive activity of mature osteoclasts. Mechanistically, Neferine suppressed RANKL-induced activation of NF-κB signaling pathway. This in turn hindered the induction and activation of NFATc1 resulting in downregulation of osteoclast marker genes closely related to differentiation, fusion as well as bone resorption. Interestingly, we found Neferine enhanced the differentiation and bone mineralization activity of MC3T3-E1 preosteoblast cells. Finally, mice treated with Neferine was protected against ovariectomy (OVX)-induced bone loss. The Neferine treatment improved bone volume following ovariectomy and also exhibited less TRAP-positive osteoclasts on bone surface. Collectively our data provide promising evidence that Neferine could be a potential therapeutic application for against osteolytic bone conditions such as osteoporosis.


Assuntos
Benzilisoquinolinas/farmacologia , Fatores de Transcrição NFATC/genética , Osteogênese/efeitos dos fármacos , Osteoporose/genética , Ligante RANK/genética , Células 3T3 , Animais , Antioxidantes/farmacologia , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Diferenciação Celular/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , NF-kappa B/genética , Osteoclastos/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Osteoporose/patologia , Transdução de Sinais/efeitos dos fármacos
17.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-817899

RESUMO

OBJECTIVE: To study the pathogenic spectrum and the clinical characteristics of viral diarrhea in children.METHODS: The study was conducted in 400 children with viral diarrhea hospitalized in Children's Hospital from January to December in 2016. The stool specimens(about 5 mL)were collected for detection from the children on the day of hospitalization. The ELISA method and PCR method were used to detect the genotypes of HUCV,HADV,HAsta V and HRV in stool specimens,and the clinical data of children were collected at the same time. RESULTS: In 2016,the total positive rate of HRV,HUCV,EAd V and HAst V in the stool specimens of children with viral diarrhea was 59%(236 cases). The positive detection rates of the four viruses were 178 cases(75.42%),68 cases(28.81%),12 cases(5.08%)and 5 cases(2.12%)respectively,of which 11.42% were double mixed infection and 41% were of unknown pathogens. The HRVG6(93.63%,147 cases)and P3(91.08%)as well as G6[P3](90.45%)combination were the popular superior type in 2016,and about 11.79%couldn't be typed. Norovirus accounted for 92.65% of the calicivirus viruses,and GⅡ accounted for 98.41%. About 81.79%of the children(193 cases)hospitalized for viral diarrhea were less than 24 months old. Pathogens were different at different peak age. The peak season of onset was fromJanuary to March and December. The main clinical manifestations were diarrhea,vomiting and fever. CONCLUSION: It is essential to determine the unknown pathogens and improve the pathogenic spectrum in children with viral diarrhea. Viral diarrhea is often accompanied by extraintestinal clinical manifestations.

18.
Parasit Vectors ; 11(1): 604, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30477573

RESUMO

BACKGROUND: Acanthamoeba spp. can cause serious human infections, including Acanthamoeba keratitis, granulomatous amoebic encephalitis and cutaneous acanthamoebiasis. Cysteine biosynthesis and the L-serine metabolic pathway play important roles in the energy metabolism of Acanthamoeba spp. However, no study has confirmed the functions of cysteine synthase (AcCS) in the cysteine pathway and phosphoglycerate dehydrogenase (AcGDH) or phosphoserine aminotransferase (AcSPAT) in the non-phosphorylation serine metabolic pathway of Acanthamoeba. METHODS: The AcCS, AcGDH and AcSPAT genes were amplified by PCR, and their recombinant proteins were expressed in Escherichia coli. Polyclonal antibodies against the recombinant proteins were prepared in mice and used to determine the subcellular localisation of each native protein by confocal laser scanning microscopy. The enzymatic activity of each recombinant protein was also analysed. Furthermore, each gene expression level was analysed by quantitative PCR after treatment with different concentrations of cysteine or L-serine. RESULTS: The AcCS gene encodes a 382-amino acid protein with a predicted molecular mass of 43.1 kDa and an isoelectric point (pI) of 8.11. The AcGDH gene encodes a 350-amino acid protein with a predicted molecular mass of 39.1 kDa and a pI of 5.51. The AcSPAT gene encodes a 354-amino acid protein with a predicted molecular mass of 38.3 kDa and a pI of 6.26. Recombinant AcCS exhibited a high cysteine synthesis activity using O-acetylserine and Na2S as substrates. Both GDH and SPAT catalysed degradation, rather than synthesis, of serine. Exogenous L-serine or cysteine inhibited the expression of all three enzymes in a time- and dose-dependent manner. CONCLUSIONS: This study demonstrated that AcCS participates in cysteine biosynthesis and serine degradation via the non-phosphorylation serine metabolic pathway, providing a molecular basis for the discovery of novel anti-Acanthamoeba drugs.


Assuntos
Acanthamoeba castellanii/enzimologia , Acanthamoeba castellanii/genética , Cisteína/metabolismo , Redes e Vias Metabólicas/genética , Serina/metabolismo , Acanthamoeba castellanii/efeitos dos fármacos , Acanthamoeba castellanii/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Cisteína/biossíntese , Cisteína/farmacologia , Cisteína Sintase/genética , Cisteína Sintase/imunologia , Cisteína Sintase/metabolismo , Sistemas de Liberação de Medicamentos , Escherichia coli/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/genética , Glicólise , Camundongos , Microscopia Confocal , Fosfoglicerato Desidrogenase/genética , Fosfoglicerato Desidrogenase/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Serina/biossíntese , Serina/farmacologia , Desidrogenase do Álcool de Açúcar/genética , Desidrogenase do Álcool de Açúcar/imunologia , Desidrogenase do Álcool de Açúcar/metabolismo , Transaminases/genética , Transaminases/imunologia , Transaminases/metabolismo
19.
Parasit Vectors ; 11(1): 379, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-29970143

RESUMO

BACKGROUND: Babesiosis is caused by the invasion of erythrocytes by parasites of the Babesia spp. Babesia microti is one of the primary causative agents of human babesiosis. To better understand the status of the disease, discovering key biomarkers of the different infection stages is crucial. RESULTS: This study investigated B. microti infection in the mouse model from 0 to 270 days post-infection (dpi), using blood smears, PCR assays and ELISA. PCR assays showed a higher sensitivity when compared to microscopic examination. Specific IgG antibodies could be detected from 7 days to 270 dpi. Two-dimensional electrophoresis was combined with western blotting and mass spectrometric analysis to screen for specific reactive antigens during both the peak parasitaemia period (7 dpi) and IgG antibody response peak period (30 dpi) by the infected mice plasma. The 87 positive reactive proteins were identified and then expressed with the wheat germ cell-free system. Protein microarrays of all 87 targeted proteins were produced and hybridized with the serial plasma of infected mice model. Based on the antigen reaction profile during the infection procedure, 6 antigens were selected and expressed in Escherichia coli. Due to an early response to IgM, lower immunoreactivity levels of IgG after two months and higher immunoreactivity level IgG during nine months, four recombinant proteins were selected for further characterization, namely rBm2D97(CCF75281.1), rBm2D33(CCF74637.1), rBm2D41(CCF75408.1) and rBm7(CCF73510.1). The diagnostic efficacy of the four recombinant protein candidates was evaluated in a clinical setting using babesiosis patient plasma. The rBm2D33 showed the highest sensitivity with a positive rate of 62.5%. Additional characterization of the two candidate proteins using a mouse vaccination assay, demonstrated that rBm2D41 could reduce peak parasitaemia by 37.4%, indicating its efficacy in preventing severe babesiosis. CONCLUSIONS: The detection technologies of microscopic examination, PCR assays and antibody tests showed different sensitivities and accuracy during the different stages of B. microti infection. Antibody detection has a unique significance for B. microti infection in the asymptomatic stages. Using immunoreactivity profiles, biomarkers for disease progression were identified and represent useful information for future the diagnosis and vaccine development for this serious disease of public health significance.


Assuntos
Babesia microti/imunologia , Babesiose/diagnóstico , Babesiose/imunologia , Progressão da Doença , Proteínas Recombinantes/isolamento & purificação , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Babesia microti/fisiologia , Babesiose/sangue , Biomarcadores/sangue , Confiabilidade dos Dados , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Eritrócitos/parasitologia , Feminino , Humanos , Imunoglobulina G/sangue , Camundongos , Parasitemia/diagnóstico , Parasitemia/parasitologia , Análise Serial de Proteínas/métodos , Proteômica , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade
20.
Infect Dis Poverty ; 7(1): 34, 2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-29699585

RESUMO

BACKGROUND: Primary pulmonary amoeba is very rare and here we report a case of a 68-year-old man presenting with primary pulmonary amoeba after undergoing chemotherapy for lung adenocarcinoma. CASE PRESENTATION: In October 2016, the man aged 68 was admitted to our hospital because of repeated cough for 8 months and hemoptysis for 1 month. He was diagnosed lung adenocarcinoma and underwent surgery in 2012 without receiving chemotherapy. In March 2016, the patients suffered recurrence of cancer and was treated with chemotherapy. After 2 months of chemotherapy, the patient had consistent cough with white sputum, and chest CT showed a local lung nodule. The physicians suspected that the patient had pulmonary infectious diseases, and he was treated with empirical antibacterial treatment. However, his symptom wasn't relieved and later the percutaneous lung biopsy found trophozites of Entamoeba histolytica. After administration of metronidazole, the symptoms of the patient were markedly relieved and the lesions were absorbed. CONCLUSIONS: In such cases where patients with pulmonary nodules were in immunodeficiency state and had adequate but ineffective anti-bacterial treatment, Entamoeba histolytica infection could be one of the rare causes. Percutaneous lung biopsy should be recommended and specific dying for parasites should be done when necessary.


Assuntos
Amebíase/diagnóstico , Antiprotozoários/uso terapêutico , Entamoeba histolytica/isolamento & purificação , Pneumopatias Parasitárias/diagnóstico , Metronidazol/uso terapêutico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Adenocarcinoma de Pulmão , Idoso , Amebíase/tratamento farmacológico , Amebíase/parasitologia , Antineoplásicos/uso terapêutico , China , Humanos , Pneumopatias Parasitárias/tratamento farmacológico , Pneumopatias Parasitárias/parasitologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/cirurgia , Masculino
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