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1.
Ecotoxicol Environ Saf ; 286: 117171, 2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39405963

RESUMO

Ambient fine particulate matter (PM2.5), a vital environmental toxicant, not only adversely affects the cardiovascular and respiratory systems but also potentially exhibits an association with intestinal inflammation and colorectal cancer (CRC). The underlying molecular mechanisms of PM2.5 impacts on CRC are still unclear. In this study, we utilized collected ambient PM2.5 and standard reference material SRM2786 to investigate the toxic effects on the colon through in vivo chronic exposure mouse and in vitro cell culture models. We employed a chronic mouse exposure model to clarify the colonic injury and gut microbiome biomarkers. Prolonged exposure to PM2.5 via oropharyngeal aspiration led to a significant rise in colonic epithelial proliferation and reduced colon length in mice. It triggered characteristics indicative of gut microbiota dysbiosis linked to inflammatory bowel disease. The gut microbiome alternations may serve as a biomarker indicating the colonic health impacts of PM2.5 exposure. PM2.5 and SRM2786-induced cytotoxicity manifested as autophagy dysregulation-mediated abnormal proliferation, IL-8 production, p62/SQSTM1 accumulation, and lysosomal membrane damage in human colon cells WiDr and Caco-2. Both PM2.5 and SRM2786 exposures led to the accumulation of p62/SQSTM1 and compromised lysosomal membrane integrity, showing impaired autophagic flux in WiDr and Caco-2 cells. Finally, we examined the correlations between atmospheric PM2.5 data and biomarkers of colonic inflammation in human population. The serum level of IL-8 was significantly correlated with regional anthropogenic pollutants. In conclusion, our findings elucidate that ambient PM2.5 exhibits adverse effects on colon health manifested as inflammation, aberrant proliferation, and gut dysbiosis, potentially mediated through autophagy dysregulation, thereby highlighting the importance of further research on the impact of environmental pollutants on gastrointestinal health.

2.
Support Care Cancer ; 31(3): 153, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36746815

RESUMO

BACKGROUND: Cancer-related fatigue is a widely prevalent global public health concern with serious consequences. Increasing evidence suggests the effectiveness of exercise intervention in treating cancer-related fatigue, but there is a lack of a summary of relevant literature on the same to help reach a clear consensus. OBJECTIVE: To summarize evidence regarding the efficacy of exercise interventions to reduce cancer fatigue, as determined in systematic reviews (SRs) and/or meta-analyses (MAs). METHOD: From inception to September 2022, PubMed (1948-2022), Embase (1974-2022), Cochrane Library (1993-2022), CINAHL (1937-2022), Web of Science (1997-2022), China Knowledge Resource Integrated Database (1999-2022), Wanfang Database (1993-2022), and Chinese Biomedical Database (1994-2022) were searched for inclusion to the study. Two reviewers independently extracted the data from the included articles. AMSTAR II was to evaluate the methodological quality of the reviews. RESULTS: A total of 46 systematic reviews were assessed for data on exercise intervention in reducing cancer-related fatigue among cancer patients. In addition, some studies have reported adverse events during the exercise intervention period. The quality of the included systematic review was found to be low or critically low. CONCLUSIONS: The present systematic review of systematic reviews supports exercise intervention for reducing cancer-related fatigue. Further higher-quality studies are warranted to improve the level of evidence for exercise interventions for application in the treatment of cancer-related fatigue.


Assuntos
Fadiga , Neoplasias , Humanos , China , Terapia por Exercício , Fadiga/etiologia , Fadiga/terapia , Neoplasias/complicações , Revisões Sistemáticas como Assunto
3.
J Bone Miner Metab ; 40(1): 66-80, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34778905

RESUMO

INTRODUCTION: Human umbilical cord blood-derived MSCs (hUC-MSCs) have the potential to differentiate into osteoblasts. This study investigated the function and potential mechanisms of a novel lncRNA LINC02381 in hUC-MSC osteogenic differentiation. MATERIALS AND METHODS: hUC-MSCs were maintained in osteogenic differentiation medium. RT-qPCR assay was performed to assess LINC02381 expression. Alizarin Red S (ARS) and alkaline phosphatase (ALP) staining were performed to evaluate osteogenic differentiation. The interaction between miR-21 and LINC0238/KLF12 was determined by luciferase reporter and RNA immunoprecipitation (RIP) assays. Chromatin immunoprecipitation (ChIP) assay was used to confirm the transcriptional regulation of KLF12 on Wnt4 promoter. The nuclear translocation of ß-catenin was evaluated using immunofluorescence. hUC-MSCs seeded on Bio-Oss Collagen scaffolds were transplanted into nude mice to assess in vivo osteogenesis. Bone formation was observed by H&E and Masson's trichrome staining. OSX and OPN levels were assessed by immunohistochemistry. RESULTS: LINC02381 was up-regulated in the clinical samples of osteoporotic patients. However, LINC02381 expression was reduced during osteogenic differentiation of hUC-MSCs. Enforced expression of LINC02381 suppressed the osteogenic differentiation of hUC-MSCs. Mechanistically, LINC02381 sponged miR-21 to enhance KLF12 expression, which led to the inactivation of Wnt/ß-catenin signaling pathway. Furthermore, miR-21 mimics or KLF12 silencing counteracted LINC02381-induced inhibition of osteogenic differentiation, whereas IWP-4 (an inhibitor of Wnt pathway) abolished this effect. CONCLUSION: In summary, LINC02381 repressed osteogenic differentiation of hUS-MSCs through sponging miR-21 to enhance KLF12-mediated inactivation of Wnt/ß-catenin pathway, indicating that LINC02381 might be a therapeutic target for osteoporosis.


Assuntos
Células-Tronco Mesenquimais , MicroRNAs , Osteogênese , RNA Longo não Codificante/genética , Animais , Diferenciação Celular , Células Cultivadas , Humanos , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Camundongos Nus , MicroRNAs/genética , Osteogênese/genética , Via de Sinalização Wnt/genética , Proteína Wnt4
4.
J Environ Manage ; 318: 115614, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35779296

RESUMO

Since the 24-hr PM2.5 (particle aerodynamic diameter less than 2.5 µm) concentration standard was regulated in Taiwan in 2012, the PM2.5 concentration has been decreasing year by year, but the ozone (O3) concentration remains almost the same. In particular, the daily maximum 8-hr average O3 (MDA8 O3) concentration frequently exceeds the standard. The goal of this study is to find a solution for reducing PM2.5 and O3 simultaneously by numerical modeling. After the Volatile Organic Compounds (VOCS)-limited and nitrogen oxides (NOX)-limited areas were defined in Taiwan, then, in total, 50 scenarios are simulated in this study. In terms of the average in Taiwan, the effect of VOCS emission reduction is better than that of NOX on the decrease in PM2.5 concentration, when the same reduction proportion (20%, 40%) is implemented. While the effect of further NOX emission reduction (60%) will exceed that of VOCS. The decrease in PM2.5 is proportional to the reduction in precursor emissions such as NOX, VOCS, sulfur dioxides (SO2), and ammonia (NH3). The lower reduction of NOX emission for whole Taiwan caused O3 increases on average but higher reduction can ease the increase, which suggests the implement of NOX emission reductions must be cautious. When comparing administrative jurisdictions in terms of grids, districts/towns, and cities/counties, it was found that controlling NOX and VOCS at a finer spatial resolution of control units did not benefit the decrease in PM2.5 but did benefit the decrease in O3. The enhanced O3 control strategies obviously cause a higher decrease of O3 throughout Taiwan due to NOX and VOCS emission changes when they are implemented in the right places. Finally, three sets of short-term and long-term goals of controlling PM2.5 and O3 simultaneously are drawn from the comprehensive rankings for all simulated scenarios, depending on whether PM2.5 or O3 control is more urgent. In principle, the short-term scenarios could be ordinary or enhanced version of O3 decrease with lower NOX/VOCS emissions, while the long-term scenario is enhanced version of O3 decrease plus high emission reductions for all precursors.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , China , Monitoramento Ambiental , Ozônio/análise , Material Particulado/análise , Taiwan , Compostos Orgânicos Voláteis/análise
5.
J Environ Sci (China) ; 118: 67-75, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35305774

RESUMO

In this study, Pb(II) was used as a target heavy metal pollutant, and the metabolism of Shewanella putrefaciens (S. putrefaciens) was applied to achieve reducing conditions to study the effect of microbial reduction on lead that was preadsorbed on graphene oxide (GO) surfaces. The results showed that GO was transformed to its reduced form (r-GO) by bacteria, and this process induced the release of Pb(II) adsorbed on the GO surfaces. After 72 hr of exposure in an S. putrefaciens system, 5.76% of the total adsorbed Pb(II) was stably dispersed in solution in the form of a Pb(II)-extracellular polymer substance (EPS) complex, while another portion of Pb(II) released from GO-Pb(II) was observed as lead phosphate hydroxide (Pb10(PO4)6(OH)2) precipitates or adsorbed species on the surface of the cell. Additionally, increasing pH induced the stripping of oxidative debris (OD) and elevated the content of dispersible Pb(II) in aqueous solution under the conditions of S. putrefaciens metabolism. These research results provide valuable information regarding the migration of heavy metals adsorbed on GO under reducing conditions due to microbial metabolism.


Assuntos
Grafite , Metais Pesados , Shewanella putrefaciens , Chumbo/metabolismo , Metais Pesados/química , Shewanella putrefaciens/metabolismo
6.
Bioorg Chem ; 109: 104710, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33611137

RESUMO

A series of 8-substituted sampangine derivatives have been designed, synthesized and tested for their ability to inhibit cholinesterase and penetrate the blood-brain barrier. Their chelating ability toward Zn2+ and other biologically relevant metal ions was also demonstrated by isothermal titration calorimetry. The new derivatives exhibited high acetylcholinesterase inhibitory activity, high blood-brain barrier penetration ability and high chelating selectivity for Zn2+. Moreover, compound 10 with the strongest binding affinity to Zn2+ was selected for further research. Western blotting analysis, transmission electron microscopy, DCFH-DA assay and paralysis experiment indicated that compound 10 suppressed the formation of Zn2+-Aß complexes, alleviated the Zn2+ induced neurotoxicity and inhibited the production of ROS catalyzed by Zn2+ in Aß42 transgenic C. elegans. Furthermore, compound 10 also inhibited the expressions of pro-inflammatory cytokines, such as NO, TNF-α, IL-6 and IL-1ß, induced by Zn2+ + Aß1-42 in BV2 microglial cells. In general, this work provided new insights into the design and development of potent metal-chelating agents for Alzheimer's disease treatment.


Assuntos
Alcaloides/química , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/química , Caenorhabditis elegans/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/química , Naftiridinas/química , Zinco/química , Animais , Animais Geneticamente Modificados , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Ibuprofeno , Microglia , Oxirredução , Ratos , Espécies Reativas de Oxigênio
7.
Bioorg Chem ; 83: 477-486, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30448726

RESUMO

A series of 6-substituted azaanthraquinone derivatives have been designed, synthesized, and their anti-inflammatory activities, antiaggregation effects on ß-amyloid proteins, anticholinesterase and neuroprotective activity were tested. The new derivatives strongly suppressed NO and iNOS production and modulate the production of cytokines by decreasing TNF-a, IL-1ß and IL-6 formation in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. Meanwhile, the derivatives exhibited a significant in vitro inhibitory activity toward the self-induced Aß aggregation. While, treatment of SH-SY5Y cells overexpressing the Swedish mutant form of human b-amyloid precursor protein (APPsw) with derivatives was associated with significant reduction of Aß42 secretion levels. Moreover, the derivatives exhibited moderate inhibitory potency toward acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Further investigations indicated that compound 7b could attenuate H2O2-induced neurotoxicity toward SH-SY5Y neuroblastoma cells and half of the synthetic compounds were predicted to be able to cross the blood-brain barrier (BBB) to reach their targets in the central nervous system (CNS) according to a parallel artificial membrane permeation assay for BBB. Taken together, azaanthraquinone derivatives targeting multiple pathogenetic factors deserves further investigation for prevention and treatment of AD.


Assuntos
Peptídeos beta-Amiloides/efeitos dos fármacos , Antraquinonas/farmacologia , Anti-Inflamatórios/farmacologia , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Antraquinonas/síntese química , Antraquinonas/química , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Barreira Hematoencefálica/efeitos dos fármacos , Butirilcolinesterase/metabolismo , Linhagem Celular Tumoral , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Estresse Oxidativo/efeitos dos fármacos , Permeabilidade , Quinolonas/síntese química , Quinolonas/química , Quinolonas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
8.
Mol Divers ; 23(3): 709-722, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30603938

RESUMO

A series of 8- and 11-substituted hybrids of oxoisoaporphine-tetrahydroisoquinoline have been designed and synthesized. The new derivatives strongly suppressed NO and iNOS production and modulated the production of cytokines by decreasing TNF-α and IL-1ß formation in lipopolysaccharide-activated BV-2 microglia and RAW 264.7 macrophages. Meanwhile, incubation of these derivatives with SH-SY5Y cells that were transfected with human APP containing the Swedish mutations significantly decreased the secretion of Aß42. Moreover, these hybrids could strongly inhibit the activity of acetylcholinesterase and butyrylcholinesterase. Further investigations in vivo indicated that the 8-substituted hybrid 3b significantly delayed paralysis caused by Aß1-42 toxicity in GMC101. In sum, these new hybrids could target multiple pathogenetic factors in Alzheimer's disease and merit further investigation.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/química , Aporfinas/química , Fragmentos de Peptídeos/química , Agregados Proteicos/efeitos dos fármacos , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/farmacologia , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Butirilcolinesterase/metabolismo , Linhagem Celular Tumoral , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-1beta/biossíntese , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Terapia de Alvo Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Fragmentos de Peptídeos/metabolismo , Células RAW 264.7 , Fator de Necrose Tumoral alfa/biossíntese
9.
Bioorg Chem ; 76: 228-236, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29195093

RESUMO

A series of 6- and 9-substituted cleistopholine derivatives has been designed, synthesized and investigated to inhibit the aggregation of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and ß-myloid (A ß). Results showed that these synthetic compounds had excellent AChE inhibitory activity and a significant in vitro inhibitory potency toward the self-induced A ß aggregation. When SH-SY5Y cells were treated with these substituted cleistopholine derivatives during they overexpressed the Swedish mutant form of human ß -amyloid precursor protein (APPsw), A ß 42 secretion levels were significantly reduced. According to a parallel artificial membrane permeation assay for BBB, seven out of these sixteen synthetic compounds probably could cross the blood-brain barrier (BBB) to reach their targets in the central nervous system (CNS).


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Antraquinonas/farmacologia , Compostos Aza/farmacologia , Inibidores da Colinesterase/farmacologia , Fragmentos de Peptídeos/antagonistas & inibidores , Acetilcolinesterase/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Antraquinonas/síntese química , Compostos Aza/síntese química , Barreira Hematoencefálica/efeitos dos fármacos , Butirilcolinesterase/metabolismo , Linhagem Celular Tumoral , Inibidores da Colinesterase/síntese química , Electrophorus , Ensaios Enzimáticos , Cavalos , Humanos , Fragmentos de Peptídeos/metabolismo , Permeabilidade/efeitos dos fármacos
10.
Sensors (Basel) ; 18(7)2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29933641

RESUMO

Radiometric calibration for imaging sensors is a crucial procedure to ensure imagery quality. One of the challenges in relative radiometric calibration is to correct detector-level artifacts due to the fluctuation in discrepant responses (spatial) and electronic instability (temporal). In this paper, the integration of the empirical mode decomposition (EMD) with Hilbert⁻Huang transform (HHT) in relative radiometric calibration was explored for a new sensor, FS-5 RSI (remote sensing instrument onboard the FORMOSAT-5 satellite). The key intrinsic mode functions (IMFs) analyzed by HHT were examined with the pre-flight datasets of the FS-5 RSI in temporal and spatial variations. The results show that the EMD⁻HHT method can stabilize and improve the radiometric quality of the FS-5 imagery as well as boost its application ability to a new level. It is noticed that the IMFs of the spatial variation would be disturbed by the instability of the temporal variation. The relative response discrepancies among detector chips can be well calibrated after considering the temporal effect. Taking a test imagery dataset of gain setting G2 as an example, the standard deviation (STD) of the discrepancy in the digital number after calibration was dramatically scaled down compared to the original ones (e.g. , PAN: 66.31 to 1.85; B1: 54.19 to 1.90; B2: 36.50 to 1.49; B3: 32.43 to 1.56; B4: 37.67 to 1.20). The good performance of pre-flight imagery indicates that the EMD⁻HHT approach could be highly practical to the on-orbit relative radiometric calibration of the FS-5 RSI sensor and is applicable to other optical sensors. To our knowledge, the proposed EMD⁻HHT approach is used for the first time to explore relative radiometric calibration for optical sensors.

11.
Opt Express ; 25(10): 12061-12068, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28788759

RESUMO

It is well known that the absorption efficiency of a suspended monolayer graphene in the optical wavelength rang is only 2.3%, which limits its optoelectronic applications. In this work, we numerically demonstrate dual-band absorption enhancement of monolayer graphene at optical frequency, with the maximum absorption efficiency reaching to about 70% under optimum conditions. The dual-band absorption enhancement arises from the excitations of surface plasmon polaritons and magnetic dipole resonances in metamaterials. The monolayer graphene is sandwiched between a periodic array of Ag nanodisks and a SiO2 spacer supported on an Ag substrate. The resonance wavelengths of two absorption bands arising from surface plasmon polaritons and magnetic dipole resonances can be easily tuned by the array period and the diameter of the Ag nanodisks, respectively. Our designed graphene light absorber may find some potential applications in optoelectronic devices, such as photodetectors.

12.
Nanotechnology ; 28(6): 065406, 2017 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-28071604

RESUMO

A facile anion exchange strategy was applied to the synthesis of porous NiS hexagonal nanoplates (NiS HNPs) as an electrode material for supercapacitors. It was found that Na2S concentration is a key factor to achieve porous NiS hexagonal nanoplates with well-defined architecture. Porous NiS hexagonal nanoplates exhibited a specific capacitance of 1897 F g-1 at a current density of 1 A g-1. NiS HNPs//activated carbon (AC) asymmetric supercapacitor (ASC) shows a long cycle lifespan (about 100% capacity retention after 4000 cycles at a current density of 3 A g-1) with a maximum energy density of 11.6 Wh kg-1 at a large loading mass of about 30 mg. Impressively, two NiS HNPs//AC ASCs in series could light up a red LED for about 30 min. The remarkable electrochemical performance of NiS HNPs is ascribed to their unique hierarchical porous architectures. The anion exchange method is a facile and versatile strategy for the synthesis of metal sulfides with high performance for energy storage.

13.
Environ Res ; 158: 753-758, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28750344

RESUMO

Aerosols affect the insolation at ground and thus the Aerosol Optical Depth (AOD, a measure of aerosol pollution) plays an important role on the variation of the Physiological Equivalent Temperature (PET) at locations with different aerosol climatology. The aerosol effects upon PET were studied for the first time at four East Asian cities by coupling a radiative transfer model and a human thermal comfort model which were previously well evaluated. Evident with the MODIS and AERONET AOD observations, the aerosol pollution at Beijing and Seoul was higher than at Chiayi (Taiwan) and Hong Kong. Based on the AERONET data, with background AOD levels the selected temperate cities had similar clear-sky PET values especially during summertime, due to their locations at similar latitudes. This also applied to the sub-tropical cities. Increase in the AOD level to the seasonal average one led to an increase in diffuse solar radiation and in turn an increase in PET for people living in all the cities. However, the heavy aerosol loading environment in Beijing and Seoul in summertime (AODs > 3.0 in episodic situations) reduced the total radiative flux and thus PET values in the cities. On the contrary, relatively lower episodic AOD levels in Chiayi and Hong Kong led to strong diffuse and still strong direct radiative fluxes and resulted in higher PET values, relative to those with seasonal averaged AOD levels. People tended to feel from "hot" to "very hot" during summertime when the AOD reached their average levels from the background level. This implies that in future aerosol effects add further burden to the thermal environment apart from the effects of greenhouse gas-induced global warming. Understanding the interaction between ambient aerosols and outdoor thermal environment is an important first step for effective mitigation measures such as urban greening to reduce the risk of human heat stress. It is also critical to make cities more attractive and enhancing to human well-being to achieve enhancing sustainable urbanization as one of the principal goals for the Nature-based Solutions.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pequim , Cidades , Monitoramento Ambiental , Hong Kong , Humanos , Modelos Biológicos , Modelos Teóricos , Seul , Taiwan , Sensação Térmica
14.
Bioorg Med Chem ; 24(22): 6031-6039, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27720328

RESUMO

A series of 8- and 11-substituted oxoisoaporphine derivatives have been designed, synthesized, and tested for their ability to inhibit cholinesterase (ChE) in vitro and in vivo, and self-induced ß-amyloid (Aß) aggregation. Their autophagy activity and blood-brain barrier (BBB) permeability were also assessed. The new derivatives exhibited high AChE inhibitory activity in vivo and in intro. Over half the derivatives exhibited a significant in vitro inhibitory activity toward the self-induced Aß aggregation. While, treatment of SH-SY5Y cells overexpressing the Swedish mutant form of human ß-amyloid precursor protein (APPsw) with derivatives was associated with significant reduction of Aß secretion levels. Moreover, one-third of the synthetic compounds were predicted to be able to cross the BBB to reach their targets in the central nervous system (CNS) according to a parallel artificial membrane permeation assay for BBB. Compounds 5b and 6b were chosen for assessing their autophagy activity. The fluorescence intensity of the BC12921 was decreased significantly after treatment with compounds. The result encourages us to study such compounds thoroughly and systematically.


Assuntos
Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/antagonistas & inibidores , Aporfinas/farmacologia , Autofagia/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Aporfinas/síntese química , Aporfinas/química , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Agregados Proteicos/efeitos dos fármacos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
15.
Angew Chem Int Ed Engl ; 54(28): 8094-9, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-26037656

RESUMO

We have developed a nanosensor for tracking cancer metastasis by noninvasive real-time whole-body optical imaging. The nanosensor is prepared by the formation of co-micelles from a poly(N-vinylpyrrolidone)-conjugated iridium(III) complex (Ir-PVP) and poly(ε-caprolactone)-b-poly(N-vinylpyrrolidone) (PCL-PVP). The near-infrared phosphorescence emission of the nanosensor could be selectively activated in the hypoxic microenvironment induced by cancer cells. The detection ability of the nanosensor was examined in cells and different animal models. After intravenous injection, the nanosensor can be effectively delivered to the lung and lymph node, and cancer cell metastasis through bloodstream or lymphatics can be quickly detected with high signal-to-background ratio by whole-body imaging and organ imaging. Moreover, the nanosensor exhibits good biocompatibility both in vitro and in vivo. The nanosensor is believed to be a powerful tool for the diagnosis of cancer metastasis.


Assuntos
Hipóxia Celular/fisiologia , Técnicas In Vitro/métodos , Irídio/química , Metástase Neoplásica/diagnóstico por imagem , Imagem Óptica/métodos , Animais , Camundongos , Nanopartículas , Cintilografia
16.
Arch Microbiol ; 196(1): 73-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24292154

RESUMO

The influence of gender and obesity on the abundance of human colonic Feacalibacterium prausnitzii is currently unclear. We collected fecal samples from 54 obese and 54 sex- and age-matched normal-weight Chinese adults and quantified the fecal F. prausnitzii as percentage of 16S rRNA gene copies of F. prausnitzii accounting to that of total gut bacteria with quantitative PCR. The fecal F. prausnitzii amount was not significantly different between obese and lean subjects. Men possessed significantly lower level of fecal F. prausnitzii than women, and the significant and positive correlation of fecal F. prausnitzii quantity with fasting glucose level was observed in men, not in women. Our results suggest that the gender effect, in addition to other factors including the geographic location, ethnicity, diet and gut transit times of study subjects, has to be considered when studying the relationship between gut F. prausnitzii and diseases.


Assuntos
Fezes/microbiologia , Bactérias Gram-Positivas/fisiologia , Obesidade/microbiologia , Adulto , China , Feminino , Trato Gastrointestinal/microbiologia , Bactérias Gram-Positivas/genética , Humanos , Masculino , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Fatores Sexuais
17.
Sci Rep ; 14(1): 12008, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796584

RESUMO

Degradation of bond strength due to corrosion of steel strands is of great importance for serviceability of prestressed concrete structures. An analytical model is proposed to demonstrate the effect of corrosion of steel strand on reduction of bond strength. Corrosion expansion force generated by steel strand corrosion before and after corrosion cracking is firstly estimated. Then, the reduced gripping effect of the concrete, change of friction coefficient between the corroded strand and reduction force on the bearing face are considered in calculating the pre-rib extrusion force. Finally, the enhancement of bond strength due to transverse confinement of stirrups is considered and the ultimate bond strength of corroded steel strand is calculated. Comparison of results between the prediction and experimental result shows the proposed model can be used to reasonably evaluate the bond strength. The prediction result of the bond strength model is affected by the degree of strand corrosion, but almost not by the drawing method.

18.
mSystems ; 9(8): e0052224, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38980058

RESUMO

The gut microbiota is essential for providing colonization resistance against pathogens. Dietary sugars markedly shift the composition of the intestinal microbiota and alter host susceptibility to enteric infections. Here, we demonstrate the effect of L-arabinose on bacterial infection by using a mouse infection model with Salmonella enterica serovar Typhimurium (S. Tm). In the presence of microbiota, L-arabinose induces a dramatic expansion of Enterobacteriaceae, thereby decreasing the microbiota diversity and causing more severe systemic infection. However, L-arabinose supplementation does not alter the disease progression of Salmonella infection in a microbiota-depleted mouse model. More importantly, short-term supplementation of L-arabinose fails to exert anti-diabetic effects in Salmonella-infected hyperglycemia mice and still promotes infection. Overall, our work reveals that a high intake of dietary L-arabinose supports a bloom of Enterobacteriaceae in Salmonella-infected gut, further accelerating the process of systemic infection.IMPORTANCEL-arabinose is a promising natural sweetener and food additive for the regulation of hyperglycemia. Since diabetic subjects are more susceptible to infections, the safety of dietary L-arabinose in diabetic patients experiencing infection remains a concern. Our findings reveal that L-arabinose exacerbates Salmonella infection outcome by inducing gut microbiota dysbiosis in mice. High dietary intake of L-arabinose may be deleterious for diabetic individuals undergoing infection.


Assuntos
Arabinose , Disbiose , Microbioma Gastrointestinal , Infecções por Salmonella , Salmonella typhimurium , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Disbiose/microbiologia , Arabinose/farmacologia , Camundongos , Infecções por Salmonella/microbiologia , Salmonella typhimurium/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Masculino , Enterobacteriaceae/efeitos dos fármacos
19.
JBI Evid Implement ; 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39445580

RESUMO

INTRODUCTION: Peripheral central venous catheters are common vascular access devices used in patients with tumors. To prevent catheter shedding and displacement, it is essential to use medical adhesives to secure the catheters. Repeated adhesion and removal of medical adhesives can weaken the barrier function of the skin, leading to medical adhesive-related skin injuries (MARSI), which can increase the patients' pain and medical expenses. OBJECTIVES: The objective of this project was to utilize the best evidence to prevent and manage MARSI in tumor patients with peripheral central venous catheters. METHODS: This evidence-based audit and feedback project was theoretically informed by the JBI Evidence Implementation Framework. The framework involves seven phases in which a project team was established; measurable criteria were selected; baseline data were collected; improvement strategies were implemented to address gaps in compliance; a follow-up audit was conducted to assess improvements in compliance; and sustainability measures were considered. The project also used the JBI Practical Application of Clinical Evidence System (PACES) for project management, including data collection and analysis. The JBI Getting Research into Practice (GRiP) approach was also used to support implementation and compliance. RESULTS: In the baseline audit, the compliance rate for the nine audit criteria was low. In the follow-up audit, the compliance rate significantly improved, with each audit criterion exceeding a minimum of 80%, and four audit criteria reaching 100%. Knowledge of MARSI among nurses and patients significantly improved (p  < 0.05) and the incidence of MARSI among patients with peripheral central venous catheters decreased. CONCLUSIONS: This project successfully enhanced nurses' compliance with MARSI prevention and management and increased the knowledge and skills of both nurses and patients about MARSI. SPANISH ABSTRACT: http://links.lww.com/IJEBH/A285.

20.
Microb Cell ; 10(3): 49-62, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36908281

RESUMO

Lactic acid bacteria (LAB) are ubiquitous microorganisms that can colonize the intestine and participate in the physiological metabolism of the host. LAB can produce a variety of metabolites, including organic acids, bacteriocin, amino acids, exopolysaccharides and vitamins. These metabolites are the basis of LAB function and have a profound impact on host health. The intestine is colonized by a large number of gut microorganisms with high species diversity. Metabolites of LAB can keep the balance and stability of gut microbiota through aiding in the maintenance of the intestinal epithelial barrier, resisting to pathogens and regulating immune responses, which further influence the nutrition, metabolism and behavior of the host. In this review, we summarize the metabolites of LAB and their influence on the intestine. We also discuss the underlying regulatory mechanisms and emphasize the link between LAB and the human gut from the perspective of health promotion.

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