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1.
Artigo em Inglês | MEDLINE | ID: mdl-32429582

RESUMO

The water resources of Central Asia play an important role in maintaining the fragile balance of ecosystems and the sustainable development of human society. However, the lack of research on the heavy metals in river waters has a far-reaching influence on public health and the sustainable development in Central Asia. In order to reveal the possible sources of the heavy metals and to assess the associated human health risks, thirty-eight water samples were collected from the rivers of the Issyk-Kul Basin during the period with low river flow (May) and the period with high river flow (July and August), and the hydrochemical compositions and major ions of heavy metals were analyzed. No changes in hydrochemical facies were observed between the two periods and the river water type was calcium bicarbonate. Carbonate dissolution and silicate weathering controlled the variation of cations and anions in river waters from the Issyk-Kul Basin. There were some differences in the sources of heavy metals in water bodies between the two periods. During the period with low river flow, heavy metals (Cr) were closely clustered with major ions, indicating that they were mainly affected by water-rock interactions. During the period with high river flow, all heavy metals studied in this paper had different sources of major ions, and the heavy metals maybe influenced by human activities. From the human health risk assessment, the hazard quotients for all samples were less than 1, reflecting that there was no noncarcinogenic risk in the river waters of the Issyk-Kul Basin during the two sampling periods. However, the water samples with carcinogenic risk of arsenic exceeding the threshold (10-4) accounted for 21.1% of the total, indicating that there were some certain carcinogenic hazards for human health via water drinking with direct oral ingestion. The results are of certain significance for the utilization and protection of water resources in the basin as well as the protection of public health.

2.
Transbound Emerg Dis ; 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32266788

RESUMO

The first documented avian influenza virus subtype H16N3 was isolated in 1975 and is currently detectable in many countries worldwide. However, the prevalence, biological characteristics and threat to humans of the avian influenza virus H16N3 subtype in China remain poorly understood. We performed avian influenza surveillance in major wild bird gatherings across the country from 2017 to 2019, resulting in the isolation of two H16N3 subtype influenza viruses. Phylogenetic analysis showed these viruses belong to the Eurasian lineage, and both viruses presented the characteristics of inter-species reassortment. In addition, the two viruses exhibited limited growth capacity in MDCK and A549 cells. Receptor-binding assays indicated that the two H16N3 viruses presented dual receptor-binding profiles, being able to bind to both human and avian-type receptors, where GBHG/NX/2/2018(H16N3) preferentially bound the avian-type receptor, while GBHG/NX/1/2018(H16N3) showed greater binding to the human-type receptor, even the mice virulence data showed the negative results. Segments from other species have been introduced into the H16N3 avian influenza virus, which may alter its pathogenicity and host tropism, potentially posing a threat to animal and human health in the future. Consequently, it is necessary to increase monitoring of the emergence and spread of avian influenza subtype H16N3 in wild birds.

3.
J Hazard Mater ; 394: 122528, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32200243

RESUMO

In this study, superparamagnetic ß-CD-MnFe2O4 with a large surface area was synthesized via a facile co-precipitation method, with ß-cyclodextrin (ß-CD) acting as a coating agent. The as-prepared ß-CD-MnFe2O4 exhibited better catalytic performance than bare MnFe2O4 in terms of activating peroxymonosulfate (PMS) to degrade 2,4-dichlorophenol (2,4-DCP) over a broad pH range of 5-11. Electron spin resonance spectroscopy (ESR) and free radical quenching experiments indicate that various active species (SO4-/OH/O2-/1O2) are generated in the ß-CD-MnFe2O4/PMS system and that pollutants trapped in the cyclodextrin cavity are quickly degraded. Various reaction parameters of the ß-CD-MnFe2O4/PMS system and the stability of ß-CD-MnFe2O4 were also investigated. The results indicate that ß-CD-MnFe2O4 is promising for use in water purification owing to its excellent magnetic separation and recovery properties and good resistance to humic acid (HA).

4.
Immunopharmacol Immunotoxicol ; 42(2): 110-118, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32066303

RESUMO

Objective: This paper aims to investigate the dynamic changes of the T-cell receptor (TCR) ß complementarity-determining region 3 (CDR3) repertoire during cyclophosphamide or Cytoxan (CTX) damage or inhibition of bone marrow hematopoiesis caused by a reduction of peripheral blood white blood cells (WBCs) in BALB/c mice.Methods: We analyze TCR CDR3 repertoire of BALB/c mice including (1) NS control group (2) CTX damage group (3) CTX damage + GM-CSF recovery group (4) CTX damage + auto-recovery group.Results: The number of WBCs in the CTX group is significantly lower than that in the NS group and after GM-CSF injection, the GM-CSF group is higher than that in the NS group. The diversity of the CTX damage group is the highest and there is a significant difference in high-frequency clonal proliferation between the CTX damage group and CTX damage + GM-CSF recovery group compared with the NS control group. In addition, the numbers of unique productive CDR3 overlapping numbers in the four experimental groups are similar.Conclusions: These data reveal that CTX significantly reduced the number of WBCs and ratio of high-frequency TCR CDR3 sequences, and indirectly increased the diversity of the TCR CDR3 repertoire. GM-CSF quickly restored the number of WBCs, and partially restored changes in the TCR CDR3 repertoire induced by CTX. Results from monitoring the dynamic changes of the TCR CDR3 repertoire can be used to assess the effects of CTX and GM-CSF on the function of peripheral blood T cells and to explore the possible underlying mechanisms.

5.
Mol Med Rep ; 21(3): 1471-1480, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32016462

RESUMO

Ovarian cancer is a prominent disease that demonstrates high incidence rates in women and often presents multidrug resistance. Propofol has been demonstrated to suppress the malignancy of various types of human cancer; however, the underlying molecular mechanisms of propofol in ovarian cancer remain largely unknown. The present study aimed to investigate whether and how propofol inhibits proliferation and cisplatin (DDP) resistance in ovarian cancer cells. Ovarian cancer cell viability was assessed by the Cell Counting kit­8 assay; apoptosis and cell cycle progression were determined by flow cytometry; the relative expression levels of microRNA (miR)­374a and forkhead box O1 (FOXO1) were analyzed using reverse transcription­quantitative PCR; the binding ability of miR­374a to FOXO1 was assessed by the dual­luciferase reporter assay; cellular sensitivity to DDP was detected using the MTT assay; and finally, the protein expression levels of FOXO1, p27, and Bcl­2­like­protein 11 (Bim) were analyzed by western blotting. Propofol reduced viability, promoted apoptosis and decreased miR­374a expression levels in A2780 cells. In addition, the viability of A2780/DDP cells in the propofol + DDP treatment group was significantly inhibited, and the apoptotic rate was increased. In addition, miR­374a overexpression increased cell viability and the proportion of cells in the S phase, and decreased the proportion of cells in the G0/G1 phase. Conversely, genetic knockdown of miR­374a exerted the opposite effects on cell viability and cell cycle progression. Moreover, miR­374a was demonstrated to bind to FOXO1. Propofol promoted the expression of FOXO1, p27 and Bim, induced cell cycle arrest and decreased ovarian cancer cell viability. In addition, treatment with propofol and DDP regulated FOXO1 and increased apoptosis of ovarian cancer cells. In conclusion, propofol downregulated miR­374a and modulated the FOXO1 pathway to reduce proliferation and DDP resistance in ovarian cancer cells.

6.
Sci Rep ; 10(1): 942, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969620

RESUMO

Using 137Cs and 210Pb dating and multi-proxy evidence from a 41-cm sediment core from Bosten Lake in China, the responses of sediment grain size to environmental changes were reconstructed over the past 150 years. After the end of the Little Ice Age, the climate of the Bosten Lake region became warmer and drier, and the lake water level decreased. The results indicated that the lowest water storage periods occurred at approximately 1920-1930 AD. Decreases in the Siberian High intensity and water vapour transport from the Indian Ocean during this period led to a reduction in the water vapour supply, which resulted in reduced lake levels in the period 1920-1930 AD. Then, the lake was at a high level until the 1960s. The water storage then declined in the 1960s. Since the 1960s, the contents of total organic carbon and total nitrogen have significantly decreased, which is closely related to the significant decline in water level and increased water salinity caused by enhanced water demands. Increased irrigation water demand as a result of expanding cultivated areas and climate change, coupled with a reduced input of water vapour, resulted in the worst water environment in approximately 1980-1990 AD. Since the late 1980s, the water level of the lake has risen, and the lake primary productivity of Bosten Lake has improved. Through the application of statistical methods to grain size data from Bosten Lake combined with the abovementioned data on climate change and human activities, two major potential factors influencing the grain size of terrigenous clastic material were revealed. The first factor, consistent with a grain size of 3.31 µm, is related to the recent increase in agricultural acreage in the Bosten Lake watershed and may reflect increases in atmospheric dust. The second factor, correlated with grain sizes of 11.48 µm and 69.18 µm, can be used to reflect changes in the lake hydrological state. It is suggested that the grain sizes of these lake sediments sensitively reflect changes in the hydrological characteristics of the basin and can be used to reconstruct the history of climate change and human activities.

7.
Medicine (Baltimore) ; 99(2): e18725, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914088

RESUMO

The NOTCH signaling pathway plays a crucial role in cell phenotype and transformation. Single nucleotide polymorphisms (SNPs) may regulate gene expression to trigger bladder cancer susceptibility. Here, we aimed to explore the relationships between genetic variants in the NOTCH pathway and bladder cancer progression.We screened SNPs located in NOTCH pathway genes using the 1000 Genomes Project dataset (CHB). A case-control cohort study including 580 bladder cancer cases and 1101 controls was conducted to genotype the candidate SNPs. The expression quantitative trait locus (eQTL) and bioinformatics analyses were performed to explore the biological function of the SNPs' host gene and their relationship. Kaplan-Meier analysis was performed to assess the association between host gene expression and bladder cancer patient prognosis.The rs7944701 in the intron of mastermind-like 2 (MAML2) had the strongest signal and was related to bladder cancer risk (OR = 1.329, 95% CI = 1.115-1.583, P = .001). eQTL analysis showed that rs7944701 with a C allele was negatively associated with mastermind-like 2 (MAML2) expression (TT versus TC/CC). Bioinformatics analysis indicated that MAML2expression was lower in bladder cancer tissues than in non-tumor tissues (P = 5.46 × 10). Additionally, bladder cancer patients with high MAML2 expression had a significantly poorer prognosis (HR = 1.53, 95% CI = 1.29-1.82, P = .010).The rs7944701 in MAML2 was strongly associated with bladder cancer susceptibility in a Chinese population. This genetic variant and its host gene could be a potential novel biomarker for individuals suffering from bladder cancer.


Assuntos
Transativadores/genética , Neoplasias da Bexiga Urinária/genética , China , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Íntrons , Estimativa de Kaplan-Meier , Masculino , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Transdução de Sinais
8.
Aust J Rural Health ; 28(2): 124-131, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31960537

RESUMO

OBJECTIVE: To study the effect of nurse-led counselling on the anxiety symptoms and the quality of life following percutaneous coronary intervention for stable coronary artery disease. DESIGN: Randomised control trial. SETTING: Rural and remote China. PARTICIPANTS: Rural and remote patients were consecutively recruited from a medical centre located in China between January and December 2014. INTERVENTIONS: The control group received standard pre-procedure information from a ward nurse on the processes of the hospitalisation and percutaneous coronary intervention, and post-procedural care. The intervention group received a structured 30-minute counselling session the day before and 24 hours after the percutaneous coronary intervention, by nurse consultants with qualifications in psychological therapies and counselling. The health outcomes were assessed by a SF-12 scale and the Seattle Angina Questionnaire at 6 and 12 months after percutaneous coronary intervention. The anxiety and depression symptoms were evaluated by a Zung anxiety and depression questionnaire. MAIN OUTCOME MEASURES: Cardiac outcomes, quality of life and mental health status. RESULTS: Eighty patients were randomly divided into control (n = 40) and intervention groups (n = 40). There was a significant increase in the scores of the three domains of Seattle Angina Questionnaire 12 months after percutaneous coronary intervention in the intervention group (P < .01). The mental health and physical health scores also increased (P < .01). In the control group, the mean scores of Zung self-rating anxiety scale 12 months following percutaneous coronary intervention were higher than the baseline scores, and higher than in the intervention group (P < .01). CONCLUSIONS: Counselling by a clinician qualified in psychological therapies and counselling significantly reduces anxiety symptoms and improves quality of life.

9.
J Ethnopharmacol ; 251: 112503, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-31891798

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Conyza blinii H.Lév. is a type of natural plant distributed in southwest of China. Its dried overground section can be used in traditional Chinese medicine (TCM) for treating infections, inflammations and occasionally cancers. CBS (Conyza blinii saponin), mainly composed of triterpenoidal saponins of Conyza blinii H.Lév. CBS is considered as the major active fraction of this species. The current investigation have focused on the mechanisms of CBS with regard to its anti-cancer activity. Hence it is of high relevance of identifying the anti-cancer efficacy of ethnomedicine. AIM OF THE STUDY: To understand the anti-cancer mechanism of CBS using both in vitro and in vivo experiments. MATERIALS AND METHODS: CBS (Conyza blinii saponin) was obtained as described previously. We tested the anti-cancer activity of CBS using in vitro HeLa cell models and in vivo animal models. We adopted immunoblot, RT-PCR (reverse transcription polymerase chain reaction), luciferase reporter assay and flow cytometry to study relevant proteins, genes, pathways and cellular ROS (reactive oxygen species) responsible for anti-cancer activity of CBS. More, 24 tumour-xenografted mice were grouped randomly as 'control', 'cisplatin' (as positive control), 'low dose' and 'high dose' groups. The IL-1ß, TNF-α, PGE2 and IL-2 in the blood serum and the tumour tissue of mice were measured. RESULTS AND CONCLUSIONS: We have found that CBS is capable of inducing apoptotic cancer cell death via both caspase-dependent and -independent pathways. CBS inhibits the activation of TGF-ß signaling pathway in a dose- and time-dependent manner. Phospho-ERK, phospho-JNK and phospho-p38 MAPK are significantly suppressed by CBS. Furthermore, some inflammation mediators including IL-1ß, TNF-α and PGE2 from animal samples were found decreased in CBS-treated mice models. In contrast, the level of IL-2, a cytokine commonly used for treating cancers, increased reversely. Last, we have discovered that CBS is able to decrease the expression of Nrf2, inhibit the activation of ARE and increase ROS level in HeLa cells. In summary, we have confirmed that the anti-cancer activity of CBS is possibly related to its TGF-ß, MAPK, Nrf2 signaling pathways as well as some cancer related inflammation mediators and cytokines.

10.
J Hazard Mater ; 384: 121345, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31605975

RESUMO

The development of highly active and multifunctional carbocatalysts modified with heteroatoms or metal species is crucial for practical environmental remediation applications. In this study, nitrogen-doped porous carbon embedded with highly dispersed CoO nanodots (CoO-N-C) was successfully prepared from a biomass-derived Schiff base polymer for the first time. The morphology analysis shows that CoO nanodots were embedded in the N doped carbon layer with size of ∼6.5 nm. CoO-N-C catalyst exhibited excellent 4-CP adsorption efficiency as well as excellent catalytic performance in the activation of peroxymonosulfate (PMS) for 4-CP degradation. Total organic carbon (TOC) removal was close to 99.7% and involved a combination of adsorption and degradation processes. Singlet oxygen (1O2) was found to be the dominant oxidative species for 4-CP degradation. The underlying mechanism of these processes were elucidated, and it was found that the introduction of CoO nanodots in CoO-N-C not only enhanced radical catalytic processes, but also significantly enhanced the non-radical catalytic processes of PMS activation. This derived from the synergistic effect between the embedded CoO nanodots and doped nitrogen for the increase of electron density on carbon surface of catalyst, thereby accelerating the electron transfer process for PMS activation and improving the catalytic performance.

11.
G3 (Bethesda) ; 10(1): 199-210, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31690562

RESUMO

NALCN (Na + leak channel, non-selective) is a conserved, voltage-insensitive cation channel that regulates resting membrane potential and neuronal excitability. UNC79 and UNC80 are key regulators of the channel function. However, the behavioral effects of the channel complex are not entirely clear and the neurons in which the channel functions remain to be identified. In a forward genetic screen for C. elegans mutants with defective avoidance response to the plant hormone methyl salicylate (MeSa), we isolated multiple loss-of-function mutations in unc-80 and unc-79 C. elegans NALCN mutants exhibited similarly defective MeSa avoidance. Interestingly, NALCN, unc-80 and unc-79 mutants all showed wild type-like responses to other attractive or repelling odorants, suggesting that NALCN does not broadly affect odor detection or related forward and reversal behaviors. To understand in which neurons the channel functions, we determined the identities of a subset of unc-80-expressing neurons. We found that unc-79 and unc-80 are expressed and function in overlapping neurons, which verified previous assumptions. Neuron-specific transgene rescue and knockdown experiments suggest that the command interneurons AVA and AVE and the anterior guidepost neuron AVG can play a sufficient role in mediating unc-80 regulation of the MeSa avoidance. Though primarily based on genetic analyses, our results further imply that MeSa might activate NALCN by direct or indirect actions. Altogether, we provide an initial look into the key neurons in which the NALCN channel complex functions and identify a novel function of the channel in regulating C. elegans reversal behavior through command interneurons.

12.
ChemSusChem ; 13(2): 341-350, 2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31709710

RESUMO

The rapid growth of CO2 emissions, especially from power plants, has led to the urgent need to directly capture and fix CO2 in the flue gas after simple purification rather than energy-intensive gas separation. Herein, imidazolium-functionalized ionic hypercrosslinked porous polymers (HCPs) bearing adjustable surface groups were straightforwardly synthesized through co-hypercrosslinking of benzylimidazole salts and crosslinker through Friedel-Crafts alkylation. Abundant microporosity and relatively high ionic moieties were obtainable in the ethyl-group-tethered ionic HCP, giving a remarkably selective CO2 capture performance with a CO2 uptake of 3.05 mmol g-1 and an ideal adsorbed solution theory (IAST) CO2 /N2 selectivity as high as 363 (273 K, 1 bar). This ionic polymer demonstrated high efficiency in the synthesis of cyclic carbonates from the coupling of various epoxides with the simulated flue gas (15 % CO2 and 85 % N2 ), giving high yields, large turnover numbers (up to 4800), and stable reusability under additive- and solvent-free conditions.

13.
Biomater Sci ; 8(2): 648-656, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31761913

RESUMO

Three SAP (self-assembling peptide)-tagged fluorinases (FLAs), namely, FLA-ELK16, FLA-L6KD and FLA-18A (named after the SAP used for tagging FLA) were successfully engineered. All three SAP-tagged FLAs could be highly over-expressed using engineered E. coli host cells despite being in the form of aggregates (inclusion bodies). It was noted that all three SAP-tagged FLAs exhibited enzymatic activity. It was also observed that all three SAP-tagged FLAs were capable of self-assembly to form nano-sized particles with different dimensions in aqueous solutions. Strikingly, one of the SAP-tagged FLA (FLA-L6KD) displayed improved enzyme activity, thermostability and reusability, which is potentially ideal for bio-transformation. FLA is an exotic enzyme that is capable of catalysing the formation of C-F bonds using inorganic fluorine ions as substrates. This significant feature enables it to incorporate [18F]-fluoride into different small molecules to generate radiopharmaceuticals in PET (positron emission tomography) labeling. In addition, fluorinase is greatly valuable in synthetic biology for incorporating the fluorine element into building blocks to produce non-natural organofluorines or as a biocatalyst for transforming non-native substrates. Our method would be a further step in making FLA-based biocatalysis even 'greener' by enhancing the enzymatic activity, thermostability and reusability of FLA through the introduction of nano-sized aggregates. Enzymes are such nontrivial biomaterials, which can be manifested in different scenarios. Our research expands their reach and tunes their properties by tagging SAP partners. Thus, this methodology can be put into the 'toolbox' of enzymologists, which can be further explored and generalised for others.

14.
Biomater Sci ; 8(1): 201-211, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31664285

RESUMO

Fe3O4 magnetic nanoparticles (MNPs), as one of the most intensively researched NPs, have a range of applications in cancer treatments. In current research, we have focused on the influences of MNPs on cancer cells. We chose polyethyleneimine (PEI) coated MNPs (PEI-MNPs) as a model and they are colloidally stable in biological media. It can be proved that PEI-MNPs result in autophagy induction via mTOR-Akt-p70S6 K and ATG7 signaling pathways. For the first time, we have reported that PEI-MNPs activate both NF-κB and TGF-ß signaling, two key pro-inflammatory pathways, in cancer cells. More significantly, we have found that autophagy induction and NF-κB and TGF-ß activation can be efficiently suppressed through the inhibition of PEI-MNP dependent reactive oxygen species (ROS) over-production. ROS are deemed as a 'double edge sword' for cancer cells, owing to the cancer-suppressing and cancer-promoting actions. Our findings would be useful for designing MNPs induced ROS anti-cancer strategies or diminishing long-term toxic effects.

15.
Anticancer Drugs ; 31(2): 131-140, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31850945

RESUMO

MiR-361-5p, a tumor-related microRNA, has been reported to be implicated in the tumorigenesis and progression of diverse types of human malignancies; however, its role in gastric carcinoma remains unclear. This study aimed to explore the biological role of miR-361-5p in gastric carcinoma and clarify the potential mechanisms involved. In the present study, miR-361-5p was found to be significantly downregulated in both gastric carcinoma tissues and cell lines. Functional studies demonstrated that enhanced expression of miR-361-5p suppressed gastric carcinoma cell proliferation in vitro, inhibited tumor growth in vivo, and induced gastric carcinoma cell apoptosis. Moreover, the tumor-suppressing effects of miR-361-5p in gastric carcinoma were abrogated by the miR-361-5p inhibitor treatment. Notably, syndecan-binding protein was downregulated by miR-361-5p via direct binding to its 3' untranslated region in gastric carcinoma cells. Furthermore, syndecan-binding protein expression was discovered to be markedly upregulated and inversely correlated with miR-361-5p expression in gastric carcinoma tissues. Mechanistic studies revealed that restoring the expression of syndecan-binding protein alleviated miR-361-5p-induced inhibitory effects on proliferation of gastric carcinoma cells. Taken together, these findings suggest that miR-361-5p functions as a tumor suppressor in gastric carcinoma by directly targeting syndecan-binding protein and that miR-361-5p might be a novel therapeutic target for gastric carcinoma.

16.
Phys Rev E ; 100(5-1): 052804, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31869990

RESUMO

Controlled cracks are useful in a wide range of applications, including stretchable electronics, microfluidics, sensors, templates, biomimics, and surface engineering. Here we report on the spontaneous formation of hierarchical crack patterns in metal (nickel) films sputter deposited on soft elastic polydimethylsiloxane (PDMS) substrates. The experiment shows that the nickel film generates a high tensile stress during deposition, which is relieved by the formation of disordered crack networks (called primary cracks). Due to the strong interfacial adhesion and soft substrate, the cracks can penetrate into the PDMS substrate deeply. The width and depth of the primary cracks both increase with increasing film thickness, whereas the crack spacing is insensitive to the film thickness. The film pieces dividing by the primary cracks can fracture further when they are triggered by an external disturbance due to the residual tensile stress, resulting in the formation of fine crack networks (called secondary cracks). The width and spacing of the secondary cracks show different behaviors in comparison to the primary cracks. The morphological characteristics, growth behaviors, and formation mechanisms of the primary and secondary cracking modes have been discussed in detail. The report in this work could provide better understanding of two distinct cracking modes with different sizes and morphologies.

17.
Opt Express ; 27(24): 35120-35128, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31878687

RESUMO

Long-term stable entanglement is a crucial aspect in the implementation of reliable quantum information processes. However, long-term continuous variable entanglement generation, especially in type-II non-degenerate optical parametric amplifier, has yet to be reported on. Here, we derive the relationship between entanglement and temperature fluctuations in the crystal of a type-II non-degenerate optical parametric amplifier, and propose a novel method for long-term stable entanglement generation by locking the temperature of the crystal. In the experiment, we obtain a 5.4 dB entanglement lasting two hours. The method holds promise in the generation of a truly usable above 10 dB entanglement and brings us closer to continuous-variable quantum information processing.

18.
Horm Cancer ; 10(4-6): 177-189, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713780

RESUMO

In hepatocellular carcinoma (HCC), the hypoxic tumor microenvironment can drive enhance tumor malignancy and recurrence. The microRNA (miRNA) miR-196-5p has been shown to modulate the progression of several cancer types, but its roles in HCC remain uncertain. In the present report we observed significant miR-196-5p downregulation in HCC tissues and cells, and we found that the expression of this miRNA significantly impaired the proliferation and metastatic potential of HCC in vitro and in vivo. We identified high-mobility group AT-hook 2 (HMGA2) as a miR-196-5p target gene that was associated with the ability of miR-196-5p to modulate the progression of HCC. Expression of miR-196-5p and HMGA2 were correlated with the clinical characteristics and poor outcomes in patients with HCC. Finally, we found that hypoxic conditions were linked with reduced miR-196-5p expression in the context of HCC. Together these results highlight the role for miR-196-5p as an inhibitor of the proliferation and metastasis of HCC via the targeting of HMGA2, with this novel hypoxia/miR-196-5p/HMGA2 pathway serving as a potential target for future therapeutic intervention.

19.
Chem Res Toxicol ; 32(12): 2479-2487, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31714069

RESUMO

The current study aimed to examine the anticancer activity of HTF-1, a cardiac glycoside (CG) isolated from Helleborus thibetanus Franch, using a cell-based model and to discover the underlying mechanisms with specific focus on autophagy. We found that HTF-1 was able to potently decrease the viability of several cancer cell lines especially for HeLa cervical carcinoma cells. It was discovered that HTF-1 dose dependently induced overproduction of ROS in HeLa cells, and the cell viability can be rescued when adding ROS scavenger N-acetyl-l-cysteine (NAC). More, we found that HTF-1 induced ROS-independent autophagy in concentration- and time-dependent manners in HeLa cells. This can be collectively verified by LC3-II and p62 abundance and also eGFP-LC3 puncta assay, bafilomycin clamp experiment, and acidotropic dye fluorescent labeling experiment. Additionally, TEM examination showed more autophagic vacuoles for HTF-1-treated HeLa cells. In HeLa cells, pretreatment with wortmannin (an inhibitor of the initial stages of autophagy to block autophagosome formation, thus, it should weaken the autophagy induction effect of HTF-1) decreased the autophagic flux and partially antagonized cell death induced by HTF-1, indicating that autophagy induced by HTF-1 played a cancer-suppressing role. Furthermore, coadministration of BAF (as a distal inhibitor of autophagy) with HTF-1 demonstrated a synergistic anticancer effect against HeLa cells. We believe that our work will enrich the understanding of CGs and especially anticarcinoma activity, also, pave the way for natural-product-based anticancer drug development.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31717917

RESUMO

In the Syr Darya River watershed, 225 samples from three different layers in 75 soil profiles were collected from irrigated areas in three different spatial regions (I: n = 29; II: n = 17; III: n = 29), and the spatial and vertical variation characteristics of potentially toxic elements (Cd, Co, Cu, Ni, and Zn) and a metallic element (Mn) were studied. The human health risks and enrichment factors were also evaluated in the Syr Darya River watershed of the Aral Sea Basin in Kazakhstan. There were significant differences in the contents of heavy metals in the different soil layers in the different sampling regions. Based on element variation similarity revealed by hierarchical cluster analysis, the elemental groupings were consistent in the different layers only in region I. For regions II and III, the clustered elemental groups were the same between surface layer A and B, but differed from those in the deep layer C. In sampling region I, the heavy metals in surface soils were significantly correlated with the ones in deep layers, reflecting that they were mainly affected by the elemental composition of parent materials. In region II, the significant correlations only existed for Cu, Mn, and Zn between the surface and deep layers. The similar phenomenon with significant correlation was also observed for heavy metals in sampling region III, except for Cd. Finally, enrichment factor was used to study the mobilization and enrichment of potentially toxic elements. The enrichment factors of Zn, Cu, and Cd in surface layer A that were greater than 1.5 accounted for 1.16%, 6.79%, and 24.36% of sampling region I, respectively. In sampling region II, the enrichment factors of Zn, Cu, Cd, and Co that were greater than 1.5 accounted for 0.03%, 4.76%, 0.54%, and 9.03% of the total area, respectively. In sampling region III, only the enrichment factors of Zn, Cu, and Cd that exceeded 1.5 accounted for 0.24%, 4.90%, and 6.89% of the total area, respectively. Although the contents of the heavy metals were not harmful to human health, the effects of human activities on the heavy metals in the irrigated soils revealed by enrichment factors have been shown in this study area.

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