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1.
J Contam Hydrol ; 261: 104287, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38219283

RESUMO

Semi-arid rivers are particularly vulnerable and responsive to the impacts of industrial contamination. Prompt identification and projection of pollutant dynamics are crucial in the accidental pollution incidents, therefore required the timely informed and effective management strategies. In this study, we collected water quality monitoring data from a typical semi-arid river. By water quality inter-correlation mapping, we identified the regularity and abnormal fluctuations of pollutant discharges. Combining the association rule method (Apriori) and characterized pollutants of different industries, we tracked major industrial pollution sources in the Dahei River Basin. Meanwhile, we deployed the integrated multivariate long and short-term memory network (LSTM) to forecast principal contaminants. Our findings revealed that (1) biological oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen, total phosphorus, and ammonia nitrogen exhibited high inter-correlations in water quality mapping, with lead and cadmium also demonstrating a strong association; (2) The main point sources of contaminant were coking, metal mining, and smelting industries. The government should strengthen the regulation and control of these industries and prevent further pollution of the river; (3) We confirmed 4 key pollutants: COD, ammonia nitrogen, total nitrogen, and total phosphorus. Our study accurately predicted the future changes in this water quality index. The best results were obtained when the prediction period was 1 day. The prediction accuracies reached 85.85%, 47.15%, 85.66%, and 89.07%, respectively. In essence, this research developed effective water quality traceability and predictive analysis methods in semi-arid river basins. It provided an effective tool for water quality surveillance in semi-arid river basins and imparts a scientific scaffold for the environmental stewardship endeavors of pertinent authorities.


Assuntos
Aprendizado Profundo , Poluentes Químicos da Água , Qualidade da Água , Monitoramento Ambiental/métodos , Amônia/análise , Poluentes Químicos da Água/análise , Rios/química , Nitrogênio/análise , Fósforo , China , Poluição da Água/análise
2.
J Contam Hydrol ; 260: 104282, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101229

RESUMO

Hulun Lake is facing significant water quality degradation, necessitating effective monitoring for safety. Traditional methods lack the necessary spatial and temporal coverage, underscoring the need for a remote sensing model. In this study, we utilized the Landsat 8 OLI dataset, incorporating cross-section monitoring and field sampling data comprehensively. Employing the random forest algorithm, we constructed a remote sensing inversion model for six water quality parameters in Hulun Lake: chlorophyll-a (Chl-a), total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH3-N), chemical oxygen demand (COD), and dissolved oxygen (DO). The model was applied to the non-freezing period of Hulun Lake from 2016 to 2021, exhibiting commendable performance and generating high-resolution maps. Time series analysis revealed that during the study period, the pollution levels of TN, TP, and COD in Hulun Lake were extremely serious, exceeding the Class V water standard of China's surface water environmental quality standard. Regional analysis indicated lower pollutant concentrations in the central lake area compared to the lake inlet. The inflowing rivers with high pollution adversely impacted Hulun Lake's water quality. To ensure the continued health of Hulun Lake's water quality, it is imperative to monitor lake water quality attentively and implement necessary measures to prevent further deterioration. This study holds crucial importance for shaping and executing ecological protection and restoration strategies for Hulun Lake.


Assuntos
Poluentes Químicos da Água , Qualidade da Água , Monitoramento Ambiental/métodos , Tecnologia de Sensoriamento Remoto , Lagos , Poluentes Químicos da Água/análise , Fósforo , Nitrogênio/análise , Aprendizado de Máquina , China
3.
Clin J Pain ; 39(6): 286-296, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37026763

RESUMO

OBJECTIVES: To determine if the frequent use of a combined biofeedback-virtual reality device improves headache-related outcomes in chronic migraine. MATERIALS AND METHODS: In this randomized, controlled pilot study, 50 adults with chronic migraine were randomized to the experimental group (frequent use of a heart rate variability biofeedback-virtual reality device plus standard medical care; n=25) or wait-list control group (standard medical care alone; n=25). The primary outcome was a reduction in mean monthly headache days between groups at 12 weeks. Secondary outcomes included mean change in acute analgesic use frequency, depression, migraine-related disability, stress, insomnia, and catastrophizing between groups at 12 weeks. Tertiary outcomes included change in heart rate variability and device-related user experience measures. RESULTS: A statistically significant reduction in mean monthly headache days between groups was not demonstrated at 12 weeks. However, statistically significant decreases in the mean frequency of total acute analgesic use per month (65% decrease in the experimental group versus 35% decrease in the control group, P <0.01) and depression score (35% decrease in the experimental group versus 0.5% increase in the control group; P <0.05) were shown at 12 weeks. At study completion, more than 50% of participants reported device satisfaction on a 5-level Likert scale. DISCUSSION: Frequent use of a portable biofeedback-virtual reality device was associated with decreases in the frequency of acute analgesic use and in depression in individuals with chronic migraine. This platform holds promise as an add-on treatment for chronic migraine, especially for individuals aiming to decrease acute analgesic use or interested in nonmedication approaches.


Assuntos
Transtornos de Enxaqueca , Adulto , Humanos , Projetos Piloto , Transtornos de Enxaqueca/terapia , Cefaleia , Biorretroalimentação Psicológica , Analgésicos/uso terapêutico , Resultado do Tratamento
4.
Chemosphere ; 318: 137875, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36646182

RESUMO

To alleviate worldwide food safety issues caused by metal contamination, an easily available material is urgently needed for extensive application. In this study, calcium magnesium phosphate fertiliser (Pcm) was applied to a Cd/Cu co-contaminated paddy field in comparison with limestone and organic fertiliser. The results showed that only Pcm is effective in simultaneously reducing Cd uptake by 56.7% and Cu uptake by 36.2% in Oryza saliva L. (rice). The rice yield, reduced mainly by Cu, also increased by 30.1% with respect to the enhancement of soil pH, cation exchange capacity and availability of phosphorus, as well as the reduction in availabilities of Cd and Cu. Additionally, Pcm dramatically shaped the bacterial community structure, with Proteobacteria and Firmicutes predominant in the soils. The beneficial genera Exiguobacterium, Citrobacter, and Acinetobacter, which are vital for phosphate dissolution and Cd/Cu immobilisation, were also enriched. The results demonstrated that the application of Pcm at 0.4% (w:w) was able to enhance both crop quantity and quality in Cd/Cu co-contaminated paddy fields by reducing Cu/Cd availability, promoting rice yield, and reshaping bacterial community structures.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Oryza/química , Fósforo , Fertilizantes , Saliva/química , Poluentes do Solo/análise , Solo/química
5.
Food Chem ; 404(Pt A): 134585, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36444014

RESUMO

The effects of chickpea protein isolate (CPI, 0.5-2 %, w/w) on the techno-functional properties of 50 % reduced-phosphate pork meat batters (RPMBs) were explored. The results showed that 1.5-2 % CPI significantly decreased the cooking loss but significantly increased the emulsion stability, hardness, gumminess, chewiness and yellowness (b*) of RPMBs (P < 0.05). CPI altered molecular characteristics of RPMBs, as demonstrated by the increased storage modulus (G'), the conversion of free water into immobilized water, the reduced intensities of the aliphatic residue Raman bands, the decreased α-helical structure and the formation of well-organized gel networks with evenly distributed small fat globules. Principal component analysis and Pearson's correlation analysis indicated that CPI-induced changes in RPMB techno-functional properties were closely related to molecular characteristics. Hierarchical cluster analysis suggested that RPMBs supplemented with 1.5-2 % CPI were highly similar in techno-functional properties to the high-phosphate group. Therefore, CPI may potentially be used to develop reduced-phosphate meat products.


Assuntos
Cicer , Carne de Porco , Carne Vermelha , Cicer/genética , Fosfatos , Suínos/genética , Água , Animais
6.
Sci Total Environ ; 795: 148870, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34243009

RESUMO

Traditional lake phytoplankton diversity studies do not take into account the impact of ecological protection and restoration project policies. Here, a difference-in-differences (DID) model, which is commonly used to analyze the relative importance of economic factors, was used to evaluate the impact of such policies on phytoplankton diversity in lakes. Dongping Lake was used as the experimental group, and the upstream Nansi Lake was used as the control group. The phytoplankton diversity index of the experimental group and the control group was used as the explanatory variable of the DID model. Six environmental and socioeconomic factors, temperature and precipitation, were used as control variables in the DID model. The effects of ecological protection and restoration project policy on phytoplankton diversity in lakes were analyzed. Under the influence of policy implementation, the phytoplankton diversity in the experimental lake was improved by 2.79% compared with that in the control lake. Temperature and precipitation were the main factors affecting phytoplankton diversity in the two connected shallow lakes in the Shandong Peninsula. This study verified that DID models can be used to quantitatively analyze the impact of ecological protection and restoration project policies on phytoplankton diversity in lakes.


Assuntos
Lagos , Fitoplâncton , China , Nitrogênio/análise , Fósforo/análise , Água
7.
Integr Cancer Ther ; 20: 1534735421996822, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33660534

RESUMO

BACKGROUND: Tamoxifen is one of the medicines for adjuvant endocrine therapy of hormone-dependent breast cancer. However, development of resistance to tamoxifen occurs inevitably during treatment. This study aimed to determine whether sensitivity of tamoxifen-resistant breast cancer cells (TAM-R) could be reinstated by tetrandrine (Tet). METHODS: All experiments were conducted in TAM-R cells derived from the MCF-7 breast cancer cell line by long-term tamoxifen exposure. Cell growth, apoptosis, and autophagy were end-points that evaluated the effect of Tet (0.9 µg/ml, 1.8 µg/ml, and 3.75 µg/ml) alone or in combination with TAM (1 µM). Cell apoptosis was determined by an ELISA assay and autophagy was determined by fluorescent staining using the Enzo autophagy detection kit. Immunoblotting was used to evaluate markers for apoptosis, autophagy, and related signal pathway molecules. RESULTS: Growth of TAM-R cells was significantly inhibited by Tet. Combination of Tet with tamoxifen induced a greater inhibition on cell growth than tamoxifen alone, which was predominantly due to enhancement of pro-apoptotic effect of TAM by Tet. Autophagy was significantly inhibited in TAM-R cells treated with Tet plus TAM as shown by increased autophagosomes and the levels of LC3-II and p62. At 0.9 µg/ml, Tet increased the levels of both apoptosis and autophagy markers. Among them increase in p53 levels was more dramatic. CONCLUSIONS: Tet as a monotherapy inhibits TAM-R cells. Tet potentiates the pro-apoptotic effect of TAM via inhibition of autophagy.


Assuntos
Benzilisoquinolinas , Neoplasias da Mama , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Apoptose , Benzilisoquinolinas/farmacologia , Benzilisoquinolinas/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Células MCF-7 , Tamoxifeno/farmacologia
8.
Int J Nanomedicine ; 13: 7633-7646, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538448

RESUMO

BACKGROUND: Development of the burgeoning number of photothermal therapy (PTT) agents has drawn a huge amount of interest, since PTT treatment is a powerful and effective alternative to traditional treatments. Optimal PTT agents should integrate some essential preconditions including negligible systemic toxicity, deep penetration into tumor tissues, and maximum laser energy absorbance. Unfortunately, only few of the PTT agents reported could meet all of the above mentioned conditions. METHODS: Here, we report a brand new PTT agent through the encapsulation of NaGdF4:Yb,Tm@ NaGdF4:Yb (UCNPs) and an organic compound (C3) into poly-e-caprolactone-polyethylene-polyglycol (PCL-PEG) (PL-UC-C3 NPs). RESULTS: UCNPs as an up-conversion material and C3 as a PTT agent both feature low cytotoxicity, and most importantly, UCNPs with superior conversion efficiency could efficiently absorb the energy of a 980 nm laser, transform the near-infrared laser light into visible light, and translate the palingenetic visible light to C3. The usage of a 980 nm laser ensures a deeper penetration and lower energy, while the highly efficient absorption and transformation process confers a cascade amplified hyperthermia for tumor treatment. CONCLUSION: In this regard, our research provides a powerful and robust breakthrough for florescence/computed tomography imaging-guided PTT treatment, lighting up the clinical application in cancer treatment.


Assuntos
Hipertermia Induzida , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Fototerapia , Polímeros/química , Tomografia Computadorizada por Raios X , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Morte Celular , Linhagem Celular Tumoral , Endocitose , Fluorescência , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Nanopartículas/ultraestrutura , Neoplasias/sangue , Neoplasias/patologia , Distribuição Tecidual , Carga Tumoral
9.
RSC Adv ; 9(1): 301-306, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-35521564

RESUMO

Multimodal molecular imaging probes have attracted much attention, and they possess great potential to accurately diagnose diseases due to the synergistic superiorities of multiple complementary imaging. Herein, a targeted biocompatible organic nanoplatform (IR-PEG-FA) with a strong optical absorption in the near-infrared window (NIR-I) for photoacoustic imaging (PAI) and excellent second near-infrared (NIR-II) fluorescence imaging property for NIR-II imaging is fabricated. The dual-modal nanoprobe is composed of the small organic dye molecule IR-1061, water-soluble poly(ethylene glycol) (PEG) and folic acid (FA) as the targeted ligands. Depending on the strength of high temporal resolution and preeminent spatial resolution, the targeted biocompatible dual-mode nanoprobe for PAI and NIR-II imaging can provide more detailed date of cancers and diseases, and enables us to specifically diagnose them through quite a precise way.

10.
Mol Cancer Res ; 12(5): 694-702, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24505127

RESUMO

UNLABELLED: Targeting amino acid metabolism has therapeutic implications for aggressive brain tumors. Asparagine is an amino acid that is synthesized by normal cells. However, some cancer cells lack asparagine synthetase (ASNS), the key enzyme for asparagine synthesis. Asparaginase (ASNase) contributes to eradication of acute leukemia by decreasing asparagine levels in serum and cerebrospinal fluid. However, leukemic cells may become ASNase-resistant by upregulating ASNS. High expression of ASNS has also been associated with biologic aggressiveness of other cancers, including gliomas. Here, the impact of enzymatic depletion of asparagine on proliferation of brain tumor cells was determined. ASNase was used as monotherapy or in combination with conventional chemotherapeutic agents. Viability assays for ASNase-treated cells demonstrated significant growth reduction in multiple cell lines. This effect was reversed by glutamine in a dose-dependent manner--as expected, because glutamine is the main amino group donor for asparagine synthesis. ASNase treatment also reduced sphere formation by medulloblastoma and primary glioblastoma cells. ASNase-resistant glioblastoma cells exhibited elevated levels of ASNS mRNA. ASNase cotreatment significantly enhanced gemcitabine or etoposide cytotoxicity against glioblastoma cells. Xenograft tumors in vivo showed no significant response to ASNase monotherapy and little response to temozolomide alone. However, combinatorial therapy with ASNase and temozolomide resulted in significant growth suppression for an extended duration of time. Taken together, these findings indicate that amino acid depletion warrants further investigation as adjunctive therapy for brain tumors. IMPLICATIONS: Findings have potential impact for providing adjuvant means to enhance brain tumor chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Asparaginase/farmacologia , Asparagina/deficiência , Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/análogos & derivados , Animais , Asparaginase/administração & dosagem , Asparaginase/metabolismo , Asparagina/metabolismo , Aspartato-Amônia Ligase/metabolismo , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Dano ao DNA , Dacarbazina/administração & dosagem , Dacarbazina/farmacologia , Sinergismo Farmacológico , Glioblastoma/tratamento farmacológico , Glioblastoma/enzimologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Glutamina/farmacologia , Humanos , Masculino , Meduloblastoma/tratamento farmacológico , Meduloblastoma/enzimologia , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Camundongos , Camundongos Nus , Temozolomida , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Bioconjug Chem ; 19(3): 731-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18278853

RESUMO

The genetic engineering, expression, and validation of a fusion protein of avidin (AV) and a chimeric monoclonal antibody (mAb) to the human insulin receptor (HIR) is described. The 15 kDa avidin monomer was fused to the carboxyl terminus of the heavy chain of the HIRMAb. The fusion protein heavy chain reacted with antibodies specific for human IgG and avidin, and had the same affinity for binding to the HIR extracellular domain as the original chimeric HIRMAb. The fusion protein qualitatively bound biotinylated ligands, but was secreted fully saturated with biotin by COS cells, owing to the high level of biotin in tissue culture medium. Chinese hamster ovary (CHO) cells were permanently transfected with a tandem vector expressing the fusion protein genes, and high expressing cell lines were isolated by methotrexate amplification and dilutional cloning. The product expressed by CHO cells had high binding to the HIR, and migrated as a homogeneous species in size exclusion HPLC and native polyacrylamide gel electrophoresis. The CHO cells were adapted to a 4 week culture in biotin depleted medium, and the HIRMAb-AV fusion protein expressed under these conditions had 1 unoccupied biotin binding site per molecule, based on a [3H]-biotin ultrafiltration assay. The HIRMAb-AV increased biotin uptake by human cells >15-fold, and mediated the endocytosis of fluorescein-biotin, as demonstrated by confocal microscopy. In summary, the HIRMAb-AV fusion protein is a new drug targeting system for humans that can be adapted to monobiotinylated drugs or nucleic acids.


Assuntos
Anticorpos Monoclonais/genética , Anticorpos Monoclonais/farmacologia , Biotina/química , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/farmacologia , Receptores de Droga/efeitos dos fármacos , Animais , Anticorpos Monoclonais/biossíntese , Avidina/química , Biotina/farmacocinética , Western Blotting , Células CHO , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Cromatografia Líquida de Alta Pressão , Cricetinae , Cricetulus , DNA Complementar/biossíntese , DNA Complementar/genética , Diálise , Sistemas de Liberação de Medicamentos , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Engenharia Genética , Humanos , Microscopia Confocal , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Soroalbumina Bovina/química , Ultrafiltração
12.
J Gene Med ; 9(7): 605-12, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17471587

RESUMO

BACKGROUND: The present study examines whether chromosomal derived forms of therapeutic genes can be delivered to brain following intravenous administration. The brain expression of a rat tyrosine hydroxylase (TH) cDNA is compared to the brain expression of a plasmid DNA encoding the 18 kb rat TH gene. METHODS: TH gene expression is measured in cell culture and in vivo in brain in experimental Parkinson's disease (PD). A total of four eukaryotic expression plasmids encoding rat TH were engineered wherein the size of the TH expression cassette ranged from 1.5 kb, in the case of the cDNA form of the gene, to 17.5 kb, in the case of the largest size genomic construct. The TH expression plasmids were delivered to either cultured cells or to rat brain in vivo with Trojan horse liposomes (THLs), which target the non-viral plasmid DNA to cells via cell membrane receptors. RESULTS: The pattern of TH gene expression in cell culture and in vivo was similar: the cDNA form of the TH gene was fast-acting with short duration of action, and the genomic form of the TH gene was slow-acting with longer duration of action. The most sustained replacement of striatal TH enzyme activity in experimental PD was produced by combination gene therapy where both the cDNA and the genomic forms of the TH gene were administered simultaneously. CONCLUSIONS: Eukaryotic expression plasmids encoding genomic forms of therapeutic genes, as large as 18 kb, can be successfully incorporated in THLs and delivered to brain following intravenous administration.


Assuntos
Encéfalo/enzimologia , DNA Complementar/genética , Terapia Genética/métodos , Genoma/genética , Doença de Parkinson/terapia , Tirosina 3-Mono-Oxigenase/genética , Animais , Encéfalo/metabolismo , Células Cultivadas , Corpo Estriado/enzimologia , Humanos , Lipossomos , Neuroglia/enzimologia , Plasmídeos/metabolismo , Ratos , Mapeamento por Restrição , Tirosina 3-Mono-Oxigenase/metabolismo
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