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1.
Endocr Rev ; 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34792130

RESUMO

The hypocretin/orexin (Hcrt/Orx) system in the perifornical lateral hypothalamus has been recognized as a critical node in a complex network of neuronal systems controlling both physiology and behavior in vertebrates. Our understanding of the Hcrt/Orx system and its array of functions and actions have grown exponentially in merely two decades. This review will examine the latest progress in discerning the roles played by the Hcrt/Orx system in the regulation of homeostatic functions and in the execution of instinctive and learned behaviors. Furthermore, the gaps that currently exist in our knowledge of sex-related differences in this field of study are discussed.

2.
ChemMedChem ; 2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34806311

RESUMO

Magnetic hyperthermia (MHT) uses magnetic iron oxide nanoparticles (MIONs) to irradiate heat when subjected to an alternating magnetic field (AMF), which then trigger a series of biological effects to realize rapid tumor-killing effects. With the deepening in research, MHT has also shown significant potential in achieving anti-tumor immunity. On the other hand, immunotherapy in cancer treatment has gained increasing attention over recent years and excellent results have generally been reported. Using MHT to activate anti-tumor immunity and clarifying its synergistic mechanism, i.e. , immunogenic cell death (ICD) and immunosuppressive tumor microenvironment (TME) reversal, can achieve a synergistically enhanced therapeutic effect on primary tumors and metastatic lesions, and this can prevent cancer recurrence and metastasis, which thus prolong survival. In this review, we discussed the role of MHT when utilized alone and combining MHT with other treatments (such as radiotherapy, photodynamic therapy, and immune checkpoint blockers) in the process of tumor immunotherapy, including antigen release, dendritic cells (DCs) maturation, and activation of CD8 + cytotoxic T lymphocytes. Finally, the challenges and future development of current MHT and immunotherapy are discussed.

3.
Nat Prod Res ; : 1-10, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34758696

RESUMO

Euphorfinoids A and B (1 and 2), a pair of ent-atisane diterpenoid epimers with a vicinal 2,3-diol moiety, together with four known analogues (3-6), were isolated from the roots of wild Euphorbia fischeriana. Their structures were elucidated by spectroscopic analysis, including extensive NMR, HR-ESIMS, NMR calculations, X-ray diffraction, and comparison with structurally related known analogues. Our bioassays have established that compound 1 displayed moderate anti-proliferative effects on Hcc1806 cell line with IC50 15.53 ± 0.21 µM, and compound 5 showed remarkable inhibitory effects against AChE with IC50 32.56 ± 2.74 µM by an in vitro screened experiment.

5.
Mol Ther Oncolytics ; 23: 220-230, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34729397

RESUMO

The progression of breast cancer is closely related to obstructive sleep apnea-hypopnea syndrome (OSAHS). Low concentrations of cannabinoids promote tumor proliferation. However, the role of cannabinoid receptors (CBs) in chronic intermittent hypoxia (CIH)-induced breast cancer has not been reported. The migration and invasion of breast cancer cell lines (MCF-7 and T47D) were measured by scratch assay and transwell assay. Gene and protein expressions were analyzed by qPCR and western blotting. Tumor xenograft mice model were established to evaluate the function of CBs. We observed that chronic hypoxia (CH) and CIH increased CBs expression and promoted migration and invasion in breast cancer. Mice grafted with MCF-7 exhibited obvious tumor growth, angiogenesis, and lung metastasis in CIH compared with CH and control. In addition, CIH induced CBs expression, which subsequently activated insulin-like growth factor-1 receptor (IGF-1R)/AKT/glycogen synthase kinase-3ß (GSK-3ß) axis. Knockdown of CBs alleviated CIH-induced migration and invasion of breast cancer in vitro. Furthermore, CIH exaggerated the malignancy of breast cancer and silencing of CBs suppressed tumor growth and metastasis in vivo. Our study contributed to understanding the role of CIH in breast cancer development modulation.

6.
Front Biosci (Landmark Ed) ; 26(10): 799-812, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34719207

RESUMO

Objective: Nucleus pulposus cells (NPCs) are cells extracted from the intervertebral disc and are important for research into intervertebral disc degeneration (IVDD). NPCs live in an avascular and relatively hypoxic environment. Cobalt chloride (CoCl2) has been used in many cell studies to mimic hypoxia. The objective of this study was to explore the possibility of using CoCl2 to induce mimetic-hypoxia for NPCs and the comparison with hypoxia (1% O2) in vitro. Materials and methods: Rat nucleus pulposus cells of Passage 3-5 were used in this research. Cell viability, rate of cell apoptosis, ROS (reactive oxygen species) generation, cell migration, extracellular pH and extracellular matrix metabolism were determined to compare the influence of hypoxia (1% O2) and CoCl2 on NPCs. Results: We found that the effects of CoCl2 on NPCs was dose-dependent. At the proper concentration, CoCl2 could be used to elicit chemical hypoxia for nucleus pulposus cells in vitro and many biological effects, analogous to physical hypoxia (1% O2), could be achieved such as enhanced cell viability, decreased apoptosis and activated extracellular matrix metabolism. On the other hand, CoCl2 mimetic-hypoxia did not affect NPCs glycolysis and migration compared to physical hypoxia. In addition, high concentration of CoCl2 (>200 µM) is harmful to NPCs with high rates of apoptosis and ECM (extracellular matrix) degradation. Conclusions: It is feasible and convenient to use CoCl2 to induce chemical mimetic hypoxia for culturing NPCs on the premise of appropriate concentration. But in aspects of cell migration and glycolysis, CoCl2 could not achieve similar results with physical hypoxia. This study may provide a convenient method and enlightenment to induce mimetic-hypoxia for researchers studying NPCs and IVVD.

7.
Front Physiol ; 12: 753914, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34751218

RESUMO

Glyphodes pyloalis Walker (Lepidoptera: Pyralidae) is a destructive mulberry pest, causing great damage to mulberry in China. Heat shock proteins (Hsps) are involved in various signal pathways and regulate lots of physiological processes in insects. The function of Hsps in G. pyloalis, however, has still received less attention. Here, we identified five Hsp genes from G. pyloalis transcriptome dataset including two Hsp70 family genes (GpHsp71.3 and GpHsp74.9) and three Hsp90 family genes (GpHsp82.4, GpHsp89, and GpHsp93.4). Quantitative Real-time PCR validation revealed that all Hsps of G. pyloalis have significant expression in pupal and diapause stage, at which the larvae arrest the development. Expressions of GpHsp71.3 and GpHsp82.4 were increased significantly after thermal treatment at 40°C, and this upregulation depended on heat treatment duration. Furthermore, silencing GpHsp82.4 by RNA interference led to a significant increase in mortality of G. pyloalis larvae under the heat stress compared to the control group. After starvation stress, the expression levels of GpHsp82.4 and GpHsp93.4 were significantly increased. At last, after being parasitized by the parasitoid wasp Aulacocentrum confusum, Hsp70 and Hsp90 genes of G. pyloalis were decreased significantly in the early stage of parasitization and this moderation was affected by time post-parasitization. This study highlights the function of G. pyloalis Hsps in response to environmental stress and provides a perspective for the control of this pest.

8.
Cell Death Discov ; 7(1): 335, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34741025

RESUMO

Endogenous clocks generate rhythms in gene expression, which facilitates the organisms to cope through periodic environmental variations in accordance with 24-h light/dark time. A core question that needs to be elucidated is how such rhythms proliferate throughout the cells and regulate the dynamic physiology. In this study, we demonstrate the role of REGγ as a new regulator of circadian clock in mice, primary MEF, and SY5Y cells. Assessment of circadian conduct reveals a difference in circadian period, wheel mode, and the ability to acclimate the external light stimulus between WT and KO littermates. Compared to WT mice, REGγ KO mice attain the phase delay behavior upon light shock at early night. During the variation of 12/12 h light/dark (LD) exposure, levels of Per1, Per2, Cry1, Clock, Bmal1, and Rorα circadian genes in suprachiasmatic nucleus are significantly higher in REGγ KO than in WT mice, concomitant with remarkable changes in BMAL1 and PER2 proteins. In cultured cells depleted of REGγ, serum shock induces early response of the circadian genes Per1 and Per2 with the cyclic rhythm maintained. Mechanistic study indicates that REGγ directly degrades BMAL1 by the non-canonical proteasome pathway independent of ATP and ubiquitin. Silencing BMAL1 abrogates the changes in circadian genes in REGγ-deficient cells. However, inhibition of GSK-3ß, a known promoter for degradation of BMAL1, exacerbates the action of REGγ depletion. In conclusion, our findings define REGγ as a new factor, which functions as a rheostat of circadian rhythms to mitigate the levels of Per1 and Per2 via proteasome-dependent degradation of BMAL1.

9.
IEEE Trans Cybern ; PP2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34606469

RESUMO

Task allocation is a crucial issue of mobile crowdsensing. The existing crowdsensing systems normally select the optimal participants giving no consideration to the sudden departure of mobile users, which significantly affects the sensing quality of tasks with a long sensing period. Furthermore, the ability of a mobile user to collect high-precision data is commonly treated as the same for different types of tasks, causing the unqualified data for some tasks provided by a competitive user. To address the issue, a dynamic task allocation model of crowdsensing is constructed by considering mobile user availability and tasks changing over time. Moreover, a novel indicator for comprehensively evaluating the sensing ability of mobile users collecting high-quality data for different types of tasks at the target area is proposed. A new Q-learning-based hyperheuristic evolutionary algorithm is suggested to deal with the problem in a self-learning way. Specifically, a memory-based initialization strategy is developed to seed a promising population by reusing participants who are capable of completing a particular task with high quality in the historical optima. In addition, taking both sensing ability and cost of a mobile user into account, a novel comprehensive strength-based neighborhood search is introduced as a low-level heuristic (LLH) to select a substitute for a costly participant. Finally, based on a new definition of the state, a Q-learning-based high-level strategy is designed to find a suitable LLH for each state. Empirical results of 30 static and 20 dynamic experiments expose that this hyperheuristic achieves superior performance compared to other state-of-the-art algorithms.

10.
Appl Opt ; 60(23): 6837-6842, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613163

RESUMO

We propose a new, to the best of our knowledge, compound technique to measure high-dynamic-range blood flow rate in a large-diameter vessel, which combines the dynamic scattering light (DLS) and the laser speckle contrast imaging (LSCI) methods, possessing the advantages of the high temporal resolution of DLS and the robust property of LSCI. By controlling the second-order spatial correlations of the laser speckle through two imaging systems, the speckle temporal intensity autocorrelation function g2(t) and the decorrelation time τc are directly measured using a high-speed camera. It turns out the enhanced spatial second-order correlation helps to measure the blood flow with higher dynamic range and that the measured parameter ß and the blood flow dynamics n were accurately determined. For further improvement the dynamic range, the modified LSCI method was adopted, and the decorrelation time as a function of blood flow rate was constructed. It reveals the feasibility of measuring the high flow rate in large-diameter vessels and provides significant guidance for the future biomedical study of the myocardial perfusion in coronary artery bypass grafting, ghost imaging, and ghost cytometry.

11.
Neurol Res ; : 1-13, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34592910

RESUMO

OBJECTIVE: Ischemic stroke is a major cause of death in the global population, with a high disability and mortality rate. Lack of regenerative ability is considered to be the fundamental cause. This study aims to determine the effect of Shh pathway, which mediates regenerative signaling in response to CNS injury, on myelin repair and Olig1 expression in focal ischemic lesions in the rat. METHODS: A model of middle cerebral artery occlusion (MCAO) was established using the intraluminal suture method where the middle cerebral artery (MCA) was restricted for 120 min. Cyclopamine, a specific inhibitor of Shh, or saline was administered 12 h after MCAO surgery and lasted for 7 days. After MCA occlusion, male Sprague-Dawley rats were randomly allocated to cyclopamine- or saline-treated groups. A group of no-injection animals after MCAO were used as controls. The Shh signaling pathway, myelinogenesis-related factor MBP and Olig1 were testedby immunohistochemistry and RT-PCR assay. RESULTS: The levels of Shh and its component Gli1 were elevated from 1 d up to 14 d following ischemia, indicating that the Shh-Gli1 axis was broadly reactivated. Treatment with cyclopamine can partially block the Shh signaling pathway, prevent myelin repair, and decrease the Olig1 expression following ischemic stroke. CONCLUSION: That blockade of Shh signaling concurrently with the creation of a lesion aggravated ischemic myelin damage, probably via its downstream effects on Olig1 transcription. Shh plays a contributory role during regeneration in the CNS, thereby providing promising new therapeutic strategies to assist in recovery from ischemic stroke.

12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1424-1428, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34627420

RESUMO

OBJECTIVE: To investigate the relationship between hypoxia inducible factor 1 (HIF1α) and Wilms' tumor 1associating protein (WTAP) expression level in t(8;21) acute myeloid leukemia cells. METHODS: The t(8;21) acute myeloid leukemia cell lines, including SKNO-1 and Kasumi-1 were treated by Echinomycin for 24 h, RT-qPCR and Western blot were used to detect the expression levels of WTAP mRNA and the protein. The CoCl 2 was used to induce the hypoxia of the cells for 24 h, the expression levels of HIF1α, WTAP protein were detected by Western blot. RESULTS: The expression level of WTAP mRNA and the protein in the echinomycin treated group was significantly lower than those in the control group (P<0.01). The expression level of WTAP protein in the CoCl2 treated group was significantly higher than those in the control group (P<0.05). CONCLUSION: The inhibition of HIF1-α could down-regulates the expression of WTAP, while the up-regulation of HIF1α could up-regulates the expression of WTAP, which shows that there is a positive correlation of HIF1α and WTAP expression. This result suggesting that HIF1α may be involves in the expression regulation of WTAP gene.


Assuntos
Proteínas de Ciclo Celular , Leucemia Mieloide Aguda , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Leucemia Mieloide Aguda/genética , Proteínas Nucleares , Fatores de Processamento de RNA , RNA Mensageiro
14.
Mol Med Rep ; 24(6)2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34643252

RESUMO

Axon regeneration after lesions to the central nervous system (CNS) is largely limited by the presence of growth inhibitory molecules expressed in myelin. Nogo­A is a principal inhibitor of neurite outgrowth, and blocking the activity of Nogo­A can induce axonal sprouting and functional recovery. However, there are limited data on the expression of Nogo­A after CNS lesions, and the mechanism underlying its influences on myelin growth remains unknown. The aim of the present study was to observe the time course of Nogo­A after cerebral ischemia/reperfusion in rats using immunohistochemistry and western blot techniques, and to test the effect of its inhibitor Nogo extracellular peptide 1­40 (NEP1­40) on neural plasticity proteins, growth­associated binding protein 43 (GAP­43) and microtubule associated protein 2 (MAP­2), as a possible mechanism underlying myelin suppression. A classic model of middle cerebral artery occlusion (MCAO) was established in Sprague­Dawley rats, which were divided into three groups: i) MCAO model group; ii) MCAO + saline group; and iii) MCAO + NEP1­40 group. Rats of each group were divided into five subgroups by time points as follows: days 1, 3, 7, 14 and 28. Animals that only received sham operation were used as controls. The Nogo­A immunoreactivity was located primarily in the cytoplasm of oligodendrocytes. The number of Nogo­A immunoreactive cells significantly increased from day 1 to day 3 after MCAO, nearly returning to the control level at day 7, increased again at day 14 and decreased at day 28. Myelin basic protein (MBP) immunoreactivity in the ipsilateral striatum gradually decreased from day 1 to day 28 after ischemia, indicating myelin loss appeared at early time points and continuously advanced during ischemia. Then, intracerebroventricular infusion of NEP1­40, which is a Nogo­66 receptor antagonist peptide, was administered at days 1, 3 and 14 after MCAO. It was observed that GAP­43 considerably increased from day 1 to day 7 and then decreased to a baseline level at day 28 compared with the control. MAP­2 expression across days 1­28 significantly decreased after MCAO. Administration of NEP1­40 attenuated the reduction of MBP, and upregulated GAP­43 and MAP­2 expression at the corresponding time points after MCAO compared with the MCAO + saline group. The present results indicated that NEP1­40 ameliorated myelin damage and promoted regeneration by upregulating the expression of GAP­43 and MAP­2 related to neuronal and axonal plasticity, which may aid with the identification of a novel molecular mechanism of restriction in CNS regeneration mediated by Nogo­A after ischemia in rats.

15.
Artigo em Chinês | MEDLINE | ID: mdl-34672459

RESUMO

Objective: Insufcient exercise blood pressure response(blunted ABPR) and lower blood pressure during the recovery period (LBP)after exercise are common abnormalities in patients with hypertrophic cardiomyopathy (HCM). The purpose of this study was to analyze the related factors of these two types of abnormal blood pressure response in HCM patients and their relationship with cardiopulmonary function. Methods: A total of 219 consecutive HCM patients who underwent CPET in Fuwai hospital were recruited from April 1, 2018 to Jan 31, 2020 with a complete clinical assessment, including electrocardiography, HOLTER, rest echocardiography and cardiac MRI. One hundred and eleven healthy age- and gender-matched volunteers enrolled as control group. Results: The incidences of blunted ABPR and LBP in HCM patients were much higher than normal control group (8.7% vs 1.8%, P=0.016; 6.8% vs 0.0%, P=0.003, respectively). In HCM group, patients with blunted ABPR combined more coronary artery disease (CAD) (P=0.029), pulmonary hypertension (PH) (P=0.002) and atrial fibrillation/flutter (P=0.036) compared with patients without blunted ABPR. Compared with HCM patients without LBP, the patients with LBP had higher rest left ventricular outflow tract (LVOT) gradient (P=0.017) and left ventricular ejection fraction (P=0.043), more incidence of LVOT obstructive (P=0.015) and systolic anterior motion (P=0.022). After Logistic regression analysis, CAD and PH were independent factor of blunted ABPR, while LBP was only independently associated with rest LVOT gradient. Blunted ABPR was associated with lower Peak VO2, peak heart rate and hear rate reserve, and higher NT-proBNP (P=0.019), VE/VO2 (P=0.000). LBP was not associated with any index of cardiopulmonary function. Conclusion: The incidences of blunted ABPR and LBP in HCM patients were much higher than normal control group. In HCM patients, CAD and PH were independent determinants of blunted ABPR, while LBP was only independently associated with rest LVOT gradient. Patients with blunted ABPR had lower cardiopulmonary function, but LBP was not associated cardiopulmonary function.


Assuntos
Cardiomiopatia Hipertrófica , Teste de Esforço , Pressão Sanguínea , Humanos , Volume Sistólico , Função Ventricular Esquerda
17.
Anal Chim Acta ; 1184: 339054, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34625272

RESUMO

Immobilized antibodies with site-specific, oriented, and covalent pattern are of great significance to improve the sensitivity of solid-phase immunoassay. Here, we developed a novel antibody conjugation strategy that can immobilize antibodies in a directional and covalent manner. In this study, an IgG-Fc binding protein (Z domain) carrying a site-specific photo-crosslinker, p-benzoyl-L-phenylalanine, and a single C-terminal cysteine (Cys) handle was genetically engineered. Upon UV irradiation, the chimeric protein enables the Cys handle to couple with the native antibody in Fc-specific and covalent conjugation pattern, resulting in a novel thiolated antibody. Thus, an approach for the covalent, directional immobilization of antibodies to maleimide-modified magnetic nanoparticles (MNPs) was developed on the basis of the crosslinking between sulfhydryl and maleimide groups. The antibody-conjugated MNPs were applied in MNP-based enzyme-linked immunosorbent assay (ELISA) for the detection of carcinoembryonic antigen. The MNP-based ELISA presented a quantification linear range of 0.1-100 ng mL-1 and detection limit of 0.02 ng mL-1, which was approximately 100 times more sensitive than the traditional microplate ELISA (2.0 ng mL-1). Thus, the proposed antibody immobilization approach can be used in surface functionalization for the sensitive detection of various biomarkers.


Assuntos
Proteínas de Transporte , Nanopartículas de Magnetita , Anticorpos , Antígenos , Magnetismo
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1582-1588, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34627444

RESUMO

AbstractObjective: To analyze the liver injury and coagulation dysfunction in COVID-19 severe/critical type patients. METHODS: The clinical data of 53 COVID-19 patients were collected from a single center in Wuhan from February 8, 2020 to March 25, 2020. The patients were divided into severe type group (38 patients) and critical type group (15 patients). The clinical characteristics, indexes of liver function, coagulation function and inflammatory markers were analyzed retrospectively. According to the degree of abnormal liver function in the process of diagnosis and treatment, the patients were divided into three groups: combined liver injury, mild abnormal liver function and normal liver function group. Statistical analysis was performed by using Student t test, Mann-Whitney U test, Kruskal-Wallis test and Chi-square test. RESULTS: Among the 53 patients, 29 were male (54.7%) and 24 were female (45.3%), the median age was 57(27-80) years old. The time from onset to admission was (11.5±7.7) days. The levels of AST, TBIL, DBIL, ALP, GGT, LDH, D-dimer, PCT and hsCRP in critical patients were higher than those in severe patients (P<0.05). The levels of Alb in critical patients was lower than those in severe patients (P<0.05). Among the 53 patients, 34 (64%) patients showed abnormal elevation of ALT, AST or TBIL, while 4 (7.5%) patients showed the criteria of COVID-19 with liver injury. After the patients were grouping according to the degree of liver dysfunction, the levels of ALP, GGT and D-dimer of the patients in the liver injury group were significantly higher than those in the normal liver function group, D-dimer levels of the patients in the liver injury group was significantly higher than those in the mild abnormal liver function group, while the levels of ALP and GGT in the mild abnormal liver function group were significantly higher than those in the normal liver function group, and the differences were statistically significant(P<0.05). CONCLUSION: In this group, the patients with COVID-19 severe/critical type have a certain proportion of liver injury accompanied by significantly increased D-dimer levels, critical type patients have more severe liver function and coagulation dysfunction, which may promote the progression of COVID-19.


Assuntos
Transtornos da Coagulação Sanguínea , COVID-19 , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Fígado , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2
19.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3299-3310, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34658216

RESUMO

A comprehensive measurement of green economic efficiency in the Yellow River Delta region can provide a reference basis for achieving ecological protection and high-quality development. We constructed an evaluation system of green economic efficiency in counties based on multi-source remote sensing data. We adopted the Super-EBM model that considered non-expected output to make a comprehensive measurement of green economic efficiency in Yellow River Delta counties, used the kernel density function estimation method to portray the characteristics of spatial and temporal evolution, and finally used the system generalized moment estimation method to identify influen-cing factors. The results showed that the comprehensive efficiency and pure technical efficiency of the green economy in the Yellow River Delta counties showed a fluctuating upward trend from 2000 to 2015. The scale efficiency showed a rapid increase and then stayed stable in a 'Γ' type trend, while the increase in comprehensive efficiency transformed from being driven by scale-technology to being led by technology. The comprehensive efficiency and pure technical efficiency of the green economy in the Yellow River Delta counties showed an evolutionary trend from 'club convergence' to 'overall convergence', with the low efficiency counties formed a 'catch-up effect' on the high efficiency counties and the scale efficiency toward a balanced and smooth development. The comprehensive efficiency of green economy and its decomposition efficiency spatially formed a 'mountain' pattern, which was high in the middle, low in the two wings, and the high value area concentrated in the headland of the Yellow River Delta and along the coast of Laizhou Bay. The high-value area showed the characteristics of a northwest-southeast shift, and the east and west wings of the Yellow River Delta formed low-value subsidence areas. Industrial structure, population concentration level, and fixed asset investment intensity had positive effects on green economic efficiency, while population urbanization rate had negative effects on green economic efficiency. There was an obvious 'environmental Kuznets' effect between green economic efficiency and economic development level.


Assuntos
Desenvolvimento Econômico , Rios , China , Indústrias , Urbanização
20.
Nanoscale ; 13(41): 17648-17654, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34664606

RESUMO

Liposome-based immunoassay (LIA) is an attractive protocol for amplifying the detection signals because of the excellent ability of liposomes to encapsulate signal marker compounds. The antigen-binding activity of the conjugated antibodies on the liposomal surface is crucial for the specificity and sensitivity of LIA. We present here a general platform to ensure that antibodies can conjugate onto the surface of liposomes in a site-specific and oriented manner. A His-handle-modified antibody with Fc region-specific and covalent conjugation was first fabricated using a photoactivatable ZBpa-His tag that was engineered using the aminoacyl-tRNA synthetase/suppressor tRNA technique. Based on the high affinity between the His tag and divalent metal ions, the novel His-modified antibody was oriented onto the surface of nickel ion-modified liposomes encapsulating horseradish peroxidase. With the prostate-specific antigen as a model, the detection efficiency of the new immunoliposomes was evaluated by chemiluminescence immunoassay. The immunoliposomes exhibited a limit of detection of 0.2 pg mL-1, which was a six time improvement compared with that of the chemical-coupled antibody-liposome conjugates. Thus, the proposed immunoliposomes are expected to hold potential applications for the sensitive detection of various biomarkers in complicated serum samples.


Assuntos
Imunoconjugados , Lipossomos , Anticorpos , Antígenos , Humanos , Imunoensaio , Masculino
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