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1.
Pharmacol Res ; : 107271, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38906202

RESUMO

Colorectal cancer is the second most prevalent and deadly cancer worldwide. The emergence of immune checkpoint therapy has provided a revolutionary strategy for the treatment of solid tumors. However, less than 5% of colorectal cancer patients respond to immune checkpoint therapy. Thus, it is of great scientific significance to develop "potentiators" for immune checkpoint therapy. In this study, we found that knocking down different DNMT and HDAC isoforms could increase the expression of IFNs in colorectal cancer cells, which can enhance the effectiveness of immune checkpoint therapy. Therefore, the combined inhibition of DNMT and HDAC cloud synergistically enhance the effect of immunotherapy. We found that dual DNMT and HDAC inhibitors C02S could inhibit tumor growth in immunocompetent mice but not in immunocompromised nude mice, which indicates that C02S exerts its antitumor effects through the immune system. Mechanistically, C02S could increase the expression of ERVs, which generated the intracellular levels of dsRNA in tumor cells, and then promotes the expression of IFNs through the RIG-I/MDA5-MAVS signaling pathway. Moreover, C02S increased the immune infiltration of DCs and T cells in microenvironment, and enhanced the efficacy of anti-PD-L1 therapy in MC38 and CT26 mice model. These results confirmed that C02S can activate IFNs through the RIG-I/MDA5-MAVS signaling pathway, remodel the tumor immune microenvironment and enhance the efficacy of immune checkpoint therapy, which provides new evidence and solutions for the development of "potentiator" for colorectal cancer immunotherapy.

2.
Ecotoxicol Environ Saf ; 260: 115068, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37257348

RESUMO

The present study systematically analyzed and evaluated the variations in chemical speciation, pollution assessment, and source identification of heavy metals in sediments of Huangpu River. The methods employed included heavy metal concentration, chemical speciation and Cu isotopic compositions analysis. Results showed that the chemical speciation of sediment-bound heavy metals, characterized by significant seasonal variation, shifted from non-residual fractions dominating in spring and summer to residual fractions dominating in autumn and winter. Precipitation was identified as an important factor influencing the chemical speciation of sediment-bound heavy metals. Furthermore, ratio of the secondary phase to the primary phase, RSP (=Cnon-residual/Cresidual) values in Huangpu River sediments were higher than 1 in spring and summer, indicating that sediment-bound heavy metals in Huangpu River were mainly composed of non-residual fractions and could potentially be released into the river water. Principal component analysis (PCA) revealed that navigation, traffic, agricultural, and industrial activities could be the potential sources of heavy metal pollution. Notably, the δ65Cu values in Huangpu River sediments were observed to be isotopically lighter (from -0.37 to +0.18 ‰), suggesting that navigation might be the primary pollution source. These results will not only provide guidance in reducing heavy metal concentrations, but also serve as a crucial basis for policy making regarding heavy metal control.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Rios/química , Estações do Ano , China , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Medição de Risco , Metais Pesados/análise
3.
Int J Mol Sci ; 23(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36499133

RESUMO

For the effective clinical antibacterial application of biomaterials, such as for wound management and tissue repair, the biomaterials need to show proper antibacterial capability as well as non-cytotoxicity. Furthermore, the material needs to have suitable mechanical characteristics for further medical use. Chitosan hydrogel is a potential candidate for various antibacterial biomedical applications due to its amine functionalities that lead to antimicrobial characteristics. Nevertheless, its antimicrobial capability is dependent upon the degree of protonation of amine groups caused by the pH value. Moreover, its mechanical compressive strength may not be high enough for clinical use if not chemically or physically crosslinked. This study utilized a novel chemical crosslinker, mercaptosuccinic acid, to improve its mechanical characteristics. The natural antibacterial agent, cinnamaldehyde, was grafted onto the crosslinked chitosan to improve its antimicrobial capability. Meanwhile, to take advantage of the thiol functionality in the mercaptosuccinic acid, the bactericidal silver nanoparticles were incorporated through silver-thiol covalent bounding. NMR analyses indicated the chitosan was successfully mercaptosuccinic acid-crosslinked and grafted with cinnamaldehyde at different ratios. Combined the results from the mechanical assessment, swelling experiments, antimicrobial assessment, and cytotoxicity assay, the chitosan hydrogel with the highest crosslinked degree and grafted with cinnamaldehyde and silver nanoparticles is of great promise for further clinical uses.


Assuntos
Quitosana , Nanopartículas Metálicas , Quitosana/química , Hidrogéis/química , Prata/química , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Tiomalatos , Aminas
4.
Angew Chem Int Ed Engl ; 60(10): 5386-5393, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33236483

RESUMO

Reprogramming tumor-associated macrophages to an antitumor M1 phenotype by photodynamic therapy is a promising strategy to overcome the immunosuppression of tumor microenvironment for boosted immunotherapy. However, it remains unclear how the reactive oxygen species (ROS) generated from type I and II mechanisms, relate to the macrophage polarization efficacy. Herein, we design and synthesize three donor-acceptor structured photosensitizers with varied ROS-generating efficiencies. Surprisingly, we discovered that the extracellular ROS generated from type I mechanism are mainly responsible for reprogramming the macrophages from a pro-tumor type (M2) to an anti-tumor state (M1). In vivo experiments prove that the photosensitizer can trigger photodynamic immunotherapy for effective suppression of the tumor growth, while the therapeutic outcome is abolished with depleted macrophages. Overall, our strategy highlights the designing guideline of macrophage-activatable photosensitizers.


Assuntos
Antineoplásicos/uso terapêutico , Reprogramação Celular/efeitos dos fármacos , Macrófagos/metabolismo , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Compostos de Anilina/síntese química , Compostos de Anilina/efeitos da radiação , Compostos de Anilina/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/efeitos da radiação , Linhagem Celular Tumoral , Feminino , Imunoterapia , Luz , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/imunologia , Neoplasias/patologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/efeitos da radiação , Células RAW 264.7
5.
Sensors (Basel) ; 20(2)2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-31963751

RESUMO

Aiming at the requirement of rapid recognition of the wearer's gait stage in the process of intelligent hybrid control of an exoskeleton, this paper studies the human body mixed motion pattern recognition technology based on multi-source feature parameters. We obtain information on human lower extremity acceleration and plantar analyze the relationship between these parameters and gait cycle studying the motion state recognition method based on feature evaluation and neural network. Based on the actual requirements of exoskeleton per use, 15 common gait patterns were determined. Using this, the studies were carried out on the time domain, frequency domain, and energy feature extraction of multi-source lower extremity motion information. The distance-based feature screening method was used to extract the optimal features. Finally, based on the multi-layer BP (back propagation) neural network, a nonlinear mapping model between feature quantity and motion state was established. The experimental results showed that the recognition accuracy in single motion mode can reach up to 98.28%, while the recognition accuracy of the two groups of experiments in mixed motion mode was found to be 92.7% and 97.4%, respectively. The feasibility and effectiveness of the model were verified.


Assuntos
Exoesqueleto Energizado , Extremidade Inferior/fisiologia , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Acelerometria/métodos , Marcha/fisiologia , Humanos , Movimento/fisiologia
6.
Environ Monit Assess ; 191(4): 253, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30919162

RESUMO

The technology for remediating heavy metal-contaminated soil is considerably limited because heavy metals do not undergo decomposition. Off-site reuse has emerged as the main technique for treating heavy metal-contaminated soil. Soil is the primary material in red brick making; and in the sintering procedure, heavy metals could solidify and stabilize within bricks. In this study, lead-, nickel-, and chromium-contaminated soils were collected from multiple agricultural fields. The sintering process was performed using a kiln that was for making red bricks. The sintering temperature was approximately 1000 °C. Soil and brick samples, before and after sintering, were analyzed for metal extraction concentration and binding form distribution. After sintering, the concentrations of Pb, Ni, and Cr determined through X-ray fluorescence approximated the concentrations in the soil. However, in the bricks, the bioavailability concentration of Pb, Ni, and Cr is less than 1% of that in the soil; the toxicity characteristic leaching procedure (TCLP) leaching concentration of Pb in the bricks was only 4% of that in the soil, and the leaching concentrations of Ni and Cr were lower than the detectable concentration. For the aqua regia extraction method, in the bricks, the Pb, Ni, and Cr were extracted and the concentrations accounted for 4.6%, 8.8%, and 9.4% of the concentrations in the soil, respectively. After sintering, more than 95% of Ni and Cr in the bricks were in residual fractions. The sintering process has the ability to stabilize the heavy metals in the contaminated soil.


Assuntos
Cromo/análise , Materiais de Construção , Monitoramento Ambiental , Chumbo/análise , Níquel/análise , Poluentes do Solo/análise , Solo/química , Agricultura , Disponibilidade Biológica , Poluição Ambiental , Metais Pesados/análise
7.
BMC Cancer ; 18(1): 758, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30041611

RESUMO

BACKGROUND: With the development of sequencing technologies, there may be some disputes on sequencing analysis. The aim of this study was to investigate different allele frequency thresholds of mutations in targeted genes on prognostic analyses using a panel of cancer associated gene exons (CAGE) in oral squamous cell carcinoma (OSCC). METHODS: Forty-six patients were included in this study. Twelve genes were sequenced and analyzed using next-generation sequencing from formalin-fixed paraffin-embedded tissues. Allele frequency thresholds of 10, 5, and 3% were used for prognostic analyses. RESULTS: With a mean sequence depth of 3199-fold, 99% of CAGE were represented by at least 10 reads. Ninety-four non-synonymous (missense [70.2%], nonsense [11.7%], splice site [10.6%], and insertion/deletion [7.5%]) mutations were detected in 40 OSCC patients with an allele frequency threshold of 10%. TP53 (78.3%), NOTCH1 (30.4%), CASP8 (13.0%), CDKN2A (10.9%), and CDH1 (6.5%) were the most frequently mutated genes. Using allele frequency thresholds of 10, 5, and 3%, there were no significant differences in clinical outcomes between patients with non-synonymous mutations and wild type genotypes. CONCLUSIONS: TP53, NOTCH1, CASP8, CDKN2A, and CDH1 are the most frequently mutated genes in OSCC patients. The allele frequency threshold used in this study does not affect the results of clinical outcome analysis.


Assuntos
Alelos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Bucais/genética , Mutação , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Adulto , Idoso , Caspase 8/genética , Inibidor p16 de Quinase Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p18/genética , Feminino , Genes p53 , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Prognóstico , Receptor Notch1/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade
8.
Environ Sci Technol ; 49(11): 6838-45, 2015 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-25955238

RESUMO

Magnetic CuO-Fe3O4 composite was fabricated by a simple hydrothermal method and characterized as a heterogeneous catalyst for phenol degradation. The effects of pH and bicarbonate ions on catalytic activity were extensively evaluated in view of the practical applications. The results indicated that an increase of solution pH and the presence of bicarbonate ions were beneficial for the removal of phenol in the CuO-Fe3O4 coupled with persulfate (PS) process. Almost 100% mineralization of 0.1 mM phenol can be achieved in 120 min by using 0.3 g/L CuO-Fe3O4 and 5.0 mM PS at pH 11.0 or in the presence of 3.0 mM bicarbonate. The positive effect of bicarbonate ion is probably due to the suppression of copper leaching as well as the formation of Cu(III). The reuse of catalyst at pH0 11.0 and 5.6 showed that the catalyst remains a high level of stability at alkaline condition (e.g., pH0 11.0). On the basis of the characterization of catalyst, the results of metal leaching and EPR studies, it is suggested that phenol is mainly destroyed by the surface-adsorbed radicals and Cu(III) resulting from the reaction between PS and Cu(II) on the catalyst. Taking into account the widespread presence of bicarbonate ions in waste streams, the CuO-Fe3O4/PS system may provide some new insights for contaminant removal from wastewater.


Assuntos
Bicarbonatos/química , Cobre/química , Poluentes Ambientais/química , Compostos Férricos/química , Compostos Orgânicos/química , Sulfatos/química , Catálise , Concentração de Íons de Hidrogênio , Íons , Microscopia Eletrônica de Varredura , Oxirredução , Fenol/química , Espectroscopia Fotoeletrônica , Difração de Raios X
9.
Acta Pharmacol Sin ; 35(2): 301-10, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24335842

RESUMO

AIM: To develop a novel 3D-QSAR approach for study of the epidermal growth factor receptor tyrosine kinase (EGFR TK) and its inhibitors. METHODS: One hundred thirty nine EGFR TK inhibitors were classified into 3 clusters. Ensemble docking of these inhibitors with 19 EGFR TK crystal structures was performed. Three protein structures that showed the best recognition of each cluster were selected based on the docking results. Then, a novel QSAR (ensemble-QSAR) building method was developed based on the ligand conformations determined by the corresponding protein structures. RESULTS: Compared with the 3D-QSAR model, in which the ligand conformations were determined by a single protein structure, ensemble-QSAR exhibited higher R2 (0.87) and Q2 (0.78) values and thus appeared to be a more reliable and better predictive model. Ensemble-QSAR was also able to more accurately describe the interactions between the target and the ligands. CONCLUSION: The novel ensemble-QSAR model built in this study outperforms the traditional 3D-QSAR model in rationality, and provides a good example of selecting suitable protein structures for docking prediction and for building structure-based QSAR using available protein structures.


Assuntos
Receptores ErbB/antagonistas & inibidores , Relação Quantitativa Estrutura-Atividade , Sítios de Ligação , Cristalografia por Raios X/métodos , Ligantes , Conformação Molecular
10.
Zhong Yao Cai ; 37(9): 1573-6, 2014 Sep.
Artigo em Zh | MEDLINE | ID: mdl-25857156

RESUMO

OBJECTIVE: To establish the quantitative model of naringin in Citrus Grandis Exocarpium by near infrared reflectance spectroscopy(NIRS). METHODS: NIRSs of 54 Citrus Grandis Exocarpium samples were collected and pretreated by TQ Analyst 8.0 software with first derivative + Norris filter. The wavebands in 10,000-4000 cm(-1) were collected and 9 numbers of factors were used. The calibration model was built with partial least squares (PLS). RESULTS: The quantitative calibration model had good correlation coefficients (r = 0.9927) and low root mean square error of calibration (RMSEC = 0.0746). Root mean square error of prediction (RMSEP) was 0.282. The average rate of recovery of validation was 101.65% (n = 9). CONCLUSION: The quantitative calibration model is trustworthy and it can be used to predict naringin in Citrus Grandis Exocarpium accurately. This simple, fast and non-destructive advantages of NIRS can be used for quality control and exploitation of Citrus Grandis Exocarpium.


Assuntos
Citrus , Espectroscopia de Luz Próxima ao Infravermelho , Calibragem , Flavanonas , Análise dos Mínimos Quadrados
11.
Artigo em Inglês | MEDLINE | ID: mdl-38039179

RESUMO

Magnetorheological (MR) fluid exhibits the ability to modulate its shear state through variations in magnetic field intensity, and is widely used for applications requiring damping. Traditional MR dampers use the current in the coil to adjust the magnetic field strength, but the accumulated heat can cause the magnetic field strength to decay if it works for a long time. In order to deal with this shortcoming, a novel MR damper is proposed in this paper, which is based on a variable displacement permanent magnet to adjust the output resistance torque and applied to an exoskeleton joint for human load transfer assistance. A finite element model is used to determine the size parameters of the magnet and separator, so that the maximum output torque is optimal and the torque is uniformly distributed with the magnet displacement. The MR damper was characterized and calibrated on the experimental bench to make it controllable. The novel design enables the torque mass density of the MR damper to reach 8.83Nmm/g, the torque volume density to reach 48.7N/mm2, and has stability for long-term operation. Based on the torque control method proposed, a preliminary human experiment is conducted. The ground reaction force (GRF) data of the subjects is analyzed here, which represents the effect of load transfer to the exoskeleton. Compared with no exoskeleton, the GRF with exoskeleton is significantly reduced: the peak GRF in early stance phase is reduced by 24.14%, and in late stance phase is reduced by 19.77%. Based on our net load benefit (NLB) and net force benefit (NFB) evaluation indicators, the effectiveness of the proposed MR damper exoskeleton for human weight bearing assistance is established.


Assuntos
Exoesqueleto Energizado , Humanos , Imãs , Extremidade Inferior , Fenômenos Mecânicos
12.
J Hazard Mater ; 465: 133247, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38141293

RESUMO

Antibiotics have attracted global attention because of their potential ecological and health risks. The emission, multimedia fate and risk of 18 selected antibiotics in the entire Yangtze River basin were evaluated by using a level Ⅳ fugacity model. High antibiotic emissions were found in the middle and lower reaches of the Yangtze River basin. The total antibiotic emissions in the Yangtze River basin exceeded 1600 tons per year between 2013 and 2021. The spatial distribution of antibiotics concentration was the upper Yangtze River > middle Yangtze River > lower Yangtze River, which is positively correlated with animal husbandry size in the basin. Temperature and precipitation increases may decrease the antibiotic concentrations in the environment. Transfer fluxes showed that source emission inputs, advection processes, and degradation fluxes contributed more to the total input and output. High ecological risks in the water environment were found in 2018, 2019, 2020, and 2021. The comprehensive health risk assessment through drinking water and fish consumption routes showed that a small part of the Yangtze River basin is at medium risk, and children have a relatively high degree of health risk. This study provides a scientific basis for the pollution control of antibiotics at the basin scale.


Assuntos
Rios , Poluentes Químicos da Água , Animais , Criança , Humanos , Antibacterianos/análise , Multimídia , Monitoramento Ambiental , China , Medição de Risco , Poluentes Químicos da Água/análise
13.
Cell Death Discov ; 10(1): 143, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490978

RESUMO

The existing conventional treatments for breast cancer, including immune checkpoint blockade, exhibit limited effects in some cancers, particularly triple-negative breast cancer. Epigenetic alterations, specifically DNMT and HDAC alterations, are implicated in breast cancer pathogenesis. We demonstrated that DNMTs and HDACs are overexpressed and positively correlated in breast cancer. The combination of DNMT and HDAC inhibitors has shown synergistic antitumour effects, and our previously designed dual DNMT and HDAC inhibitor (termed DNMT/HDACi) 15a potently inhibits breast cancer cell proliferation, migration, and invasion and induces apoptosis in vitro and in vivo. Mechanistically, 15a induces a viral mimicry response by promoting the expression of endogenous retroviral elements in breast cancer cells, thus increasing the intracellular level of double-stranded RNA to activate the RIG-I-MAVS pathway. This in turn promotes the production of interferons and chemokines and augments the expression of interferon-stimulated genes and PD-L1. The combination of 15a and an anti-PD-L1 antibody had an additive effect in vivo. These findings indicate that this DNMT/HDACi has immunomodulatory functions and enhances the effectiveness of immune checkpoint blockade therapy. A novel dual DNMT and HDAC inhibitor induces viral mimicry, which induces the accumulation of dsRNA to activate tumoral IFN signalling and cytokine production to enhance the immune response in breast cancer.

14.
J Environ Manage ; 120: 114-9, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23507250

RESUMO

Arsenic (As) in groundwater and surface water is a worldwide problem possessing a serious threat to public health. In this study, a magnetic ferrite, was synthesized and investigated for its As(V) removal efficiency. The adsorption of As(V) by magnetic ferrite exhibited an L-shaped nonlinear isotherm, suggesting limiting binding sites on the adsorbent surface. The As K-edge X-Ray Absorption Near-Edge Structure (XANES) revealed that the adsorbed As(V) on ferrite was not reduced to more toxic As(III) by Fe(2+) in the ferrite structure. The maximum As adsorption capacity of ferrite was 14 mg/g at pH 3 and decreased with increasing pH due to enhanced electrostatic repulsion between As(V) and the adsorbent surface. Desorption of As(V) using six different acid and salt solutions showed that the desorption rate decreased in an order of H3PO4 > Na3PO4 > H2SO4 > Na2SO4 > HCl > HNO3. These results suggest that magnetic ferrite without surface modification is an effective adsorbent for removing As(V) from water, which was confirmed by the effective removal of As(V) from contaminated groundwater using this material. The used material can then be recovered using a magnet because of its paramagnetism; the adsorbed As(V) on the material can be recovered using H3PO4 or Na3PO4 solutions.


Assuntos
Arseniatos/química , Compostos Férricos/química , Purificação da Água/métodos , Absorção
15.
Huan Jing Ke Xue ; 44(6): 3184-3197, 2023 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-37309937

RESUMO

Taipu River is a river spanning two provinces and one city in a demonstration area in the Yangtze River Delta on an ecologically friendly developmentand an important water source in the upper reaches of the Huangpu River in Shanghai. To understand the multi-media distribution characteristics, pollution status, and ecological risk of heavy metals in the Taipu River, the contents of heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb, and Zn) in the sediments of Taipu River were analyzed, and the pollution status and potential ecological risk were evaluated using the Nemerow comprehensive pollution index, geo-accumulation index, and potential ecological risk index methods. In addition, the health risk assessment model was used to assess the health risk of heavy metals in surface water of Taipu River. The results showed that the concentrations of Cd, Cr, Mn, and Ni in the surface water of Taipu River exceeded the class Ⅲ water limit at the upstream point in spring; the concentrations of Sb exceeded the class Ⅲ water limit at all points in winter; the average value of As exceeded the class Ⅲ water limit in overlying water during the wet season; and the average values of As and Cd exceeded the class Ⅲ water limit in pore water during the wet season. The health risk assessment of surface water implied that both adults and children had higher health risk in spring and lower health risk in other seasons. The health risk of children was significantly higher than that of adults, and it mainly came from chemical carcinogenic heavy metal elements As, Cd, and Cr. The average contents of Co, Mn, Sb, and Zn in Taipu River sediments in the four seasons all exceeded the Shanghai soil baseline; the average contents of As, Cr, and Cu in summer, autumn, and winter exceeded the Shanghai soil baseline; and the average contents of Cd, Ni, and Pb in summer and winter exceeded the Shanghai soil baseline. The evaluation results of the Nemerow comprehensive pollution index and geo-accumulation index showed that the pollution degree of the middle reaches of Taipu River was higher than that of the upper and lower reaches, and the Sb pollution was more serious. The potential ecological risk index method revealed that the Taipu River sediment was at a low risk. Cd had a high contribution in both the wet and dry seasons and could be regarded as the main heavy metal of potential ecological risk in the Taipu River sediment.

16.
J Environ Monit ; 14(1): 105-15, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22072144

RESUMO

Fifty-eight sediment samples were collected in 2009 from the bottom of river mouths near Kaohsiung Harbor (Taiwan) and the harbor channel for the analyses of polycyclic aromatic hydrocarbons (PAHs) using gas chromatography-mass spectrometry (GC-MS). Concentrations of total PAHs varied from 39 to 30,521 ng g(-1) (dry weight); samples collected from the mouths of Love River, Canon River, Jen-Gen River, and Salt River showed the highest PAHs concentrations. This indicates that the major sources of sediment PAHs come from those polluted urban rivers and the harbor channel. In samples collected from the Salt River mouth, approximately 43% of the PAHs are identified as PAHs with 2 or 3 rings. However, samples collected from other locations contain predominantly PAHs with 4 rings (32 to 42%) or 5 and 6 rings (36 to 44%). Emissions from traffic-related sources and waste incineration contribute to the majority of PAHs found in most channel and river mouth sediments. However, coal/oil combustion is the main cause of high concentrations of PAHs observed in the Salt River mouth sediments. Principal component analyses with multivariate linear regression (PCA/MLR) have been used to further quantify the source contributions, and the results show that the contributions of coal/oil combustion, traffic-related and waste incineration are 37%, 33% and 30%, respectively.


Assuntos
Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Análise por Conglomerados , Monitoramento Ambiental , Modelos Lineares , Análise Multivariada , Análise de Componente Principal , Água do Mar/química , Taiwan
17.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): m1419-20, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23284382

RESUMO

There are two independent mol-ecules with similar configurations in the asymmetric unit of the title complex, [Pd(C(4)H(3)N(2))I(C(18)H(15)P)(2)]. In each mol-ecule, the geometry around the Pd atom is distorted square-planar, with the Pd atom displaced by 0.0549 (12) and 0.0734 (13) Šfrom the least-squares plane of the I-P-P-C atoms. The PPh(3) ligands are in trans positions, with P-Pd-P angles of 173.12 (4) and 170.29 (4)°, while the pyrazinyl ligands and I atoms, also trans to each other, form C-Pd-I angles of 179.38 (12) and 178.44 (12)°. In the crystal, C-H⋯π inter-actions occur, resulting in a three-dimensional supramolecular architecture.

18.
Artigo em Inglês | MEDLINE | ID: mdl-35030082

RESUMO

This paper presents the E-LEG, a novel semi-passive lower-limb exoskeleton for worker squatting assistance, with motorized tuning of the assistive squatting height. Compared with other passive industrial exoskeletons for the lower-limbs, the E-LEG presents novel design features namely inertial sensor for measuring the tilt angle of thigh and the novel electromagnetic switch for adjusting squat height. These features could enhance the effectiveness of the system. In addition to the introduction to exoskeleton design, this paper also reports the systematic experimental evaluation of human subjects. With the assistance of different conditions, the variability of muscular activity was evaluated in long-term static squatting task. The set of metrics to evaluate the effect of the device included leg muscle activity, plantar pressure fluctuation, plantar pressure center fluctuation and gait angles. Results show that the exoskeleton can reduce the muscular activity of the user during squatting, and it will have little affect the normal gait of the user during walking. In this study, we found that the E-LEG exoskeleton has potential effectiveness in reducing the muscular strain on long-term continuous squatting activities.


Assuntos
Exoesqueleto Energizado , Fenômenos Biomecânicos , Marcha/fisiologia , Humanos , Perna (Membro)/fisiologia , Extremidade Inferior , Caminhada
19.
Huan Jing Ke Xue ; 43(6): 3066-3076, 2022 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-35686776

RESUMO

The surface sediments were collected from 25 sampling points in the Qingpu District of the Yangtze River Delta integration demonstration area, and the total organic carbon (TOC), total nitrogen (TN), organic carbon isotope (δ13C), and nitrogen isotope (δ15N) content in the samples were analyzed. The distribution characteristics and potential sources of organic matter in the surface sediments were discussed in detail, and the organic pollution index was also evaluated. The results showed that the ω(TOC) in the surface sediments of 31 sampling points in Qingpu District was 0.21%-3.55%, with an average value of 1.18%; ω(TN) ranged from 0.02% to 0.23%, with an average value of 0.09%. The δ13C ranged from -28.04‰ to -10.80 ‰, with an average of -22.28‰, and the δ15N ranged from 2.28‰ to 11.19‰, with an average of 5.76‰. The TOC content was significantly correlated with the TN content. Source analysis showed that the organic matter in the surface sediments of the study area was mainly affected by soil organic matter, sewage organic matter, and terrestrial plants. The calculation results of the contribution rate based on IsoSource software showed that the relative contribution rate of soil organic matter was relatively high (0.3%-96.8%), and domestic sewage had a certain contribution to the organic matter source of most sampling points. In addition, the selected end-member substances had certain differences in the contribution of organic matter sources in samples of different land use types. The evaluation index of organic pollution in the surface sediments of the study area ranged from 0.006-0.745, with an average value of 0.163, indicating that the organic pollution of the study area was considered lightly polluted. Among them, the pollution of sampling points around the Jinze Reservoir was more serious than that in other areas, indicating that there was a potential risk of eutrophication in this area, which requires certain attention.


Assuntos
Rios , Poluentes Químicos da Água , Carbono/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Nitrogênio/análise , Esgotos/análise , Solo , Poluentes Químicos da Água/análise
20.
Investig Clin Urol ; 63(3): 262-272, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35437960

RESUMO

PURPOSE: The selection of open prostatectomy (OP) over transurethral laser surgery is controversial for large volume prostates. Thus, we aim to compare the efficacy and safety of transurethral laser versus OP, and provide the latest evidence of clinical practice for large-sized benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: This meta-analysis used Review Manager V5.3 software and the systematic literature search of Cochrane Library, Embase, PubMed, and Web of Science datasets was performed for citations published from 2000 to 2020 that compared transurethral laser with OP for the treatment of large BPH. Variables of interest assessing the two techniques included clinical characteristics, and the perioperation-, effectiveness-, and complication-related outcomes. RESULTS: The meta-analysis included twelve studies containing 1,514 patients, with 792 laser and 722 OP. The transurethral laser group was associated with shorter hospital stay and catheterization duration, and less hemoglobin decreased in the perioperative variables. There was no significant difference in the international prostate symptom score, post-void residual urine volume, maximum flow rate, and quality of life score. Transurethral laser group had a significantly lower incidence of blood transfusion than OP group (odds ratio, 0.10; 95% confidence interval, 0.05 to 0.19; p<0.001; I²=8%), and no statistical differences were found with respect to the other complications. CONCLUSIONS: Both OP and transurethral laser prostatectomy are effective and safe treatments for large prostate adenomas. With these advantages of less blood loss and transfusion, and shorter catheterization time and hospital stay, laser may be a better choice for large BPH.


Assuntos
Hiperplasia Prostática , Ressecção Transuretral da Próstata , Humanos , Lasers , Masculino , Prostatectomia/efeitos adversos , Prostatectomia/métodos , Hiperplasia Prostática/cirurgia , Qualidade de Vida , Ressecção Transuretral da Próstata/efeitos adversos , Ressecção Transuretral da Próstata/métodos , Resultado do Tratamento
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