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The inline gas-liquid cyclone separator has been gradually used in oil & gas industry due to its high separation efficiency and less footprint. However, under the inlet flow conditions with large range of gas volume fractions, the research on structure design and separation performance are seriously insufficient. The preliminary structural design of the inline gas-liquid separator was carried out according to the particle separation theory, and the key structural parameters were optimized by using the Response Surface Method (RSM) together with Computational Fluid Dynamics (CFD). The structure optimization has improved the degassing efficiency by 17.44% and dehydration efficiency by 7.59%. With air and water as working medium, the separation performance of the inline gas-liquid cyclone separator was experimentally investigated in laboratory under a large range of gas volume fractions. The results show that the separation efficiency for both degassing and dehydration can exceed 80% with the inlet gas volume fraction ranges from 0.2 to 0.8. The optimum normalized flow split and liquid volume flow rate are 0.9 –1.2 and 8 m3/h, respectively. [ABSTRACT FROM AUTHOR]

Background: Most arthropods are famous for their large reproductive capacity, with the ovary playing a vital role in the process. The study of the regulatory mechanisms of ovarian development may have the potential for a reproduction‐based pest management strategy. GATA‐binding transcription factors (GATAs) as important regulatory factors mediate many physiological processes, including development, immunity, insecticide resistance and reproduction. The Pannier (pnr), a member of GATA family, was confirmed to be involved in ovarian development of Bactrocera dorsalis in our previous study. However, the direct evidence of pnr regulating the fly ovarian development is still lacking. Results: We used CRISPR/Cas9 to create Bdpnr loss‐of‐function mutations. Homozygous Bdpnr−/− mutants were nonviable, with most individuals dying during embryogenesis, some surviving to the larval stages, and the remaining few dying during pupation. In contrast, heterozygous individuals reached the adult stage, but ovarian development was disrupted, with concomitant decreases in egg laying and hatching rates. We also found that two genes encoding vitellogenin proteins (BdVg1 and BdVg2) and the vitellogenin receptor (BdVgR) were significantly down‐regulated in heterozygous mutants compared to wild‐type controls. Conclusion: These results indicate that Bdpnr is required for embryonic and post‐embryonic development, including the formation of ovaries. Bdpnr could therefore be considered as a molecular target for tephritid fly pest control. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: The current diagnosis of Parkinson's disease (PD) is mainly based on the typical clinical manifestations. However, 60% dopaminergic neurons have died when the typical clinical manifestations occur. Predictive neurobiomarkers may help identify those PD patients having non-motor disorders or in different stage and achieving the aim of early diagnosis. Up to date, few if any neuroimaging techniques have been described useful for non-movement disorders diagnosis in PD patients. Here, we investigated the alteration of metabolites in PD patients in different stage of PD and non-motor symptoms including sleep, gastrointestinal and cognitive dysfunction, by using the 1H-MRS. Methods: A total of 48 subjects were included between 2017 and 2019: 37 PD (15 men, age 47–82 years) and 11 healthy people (8 men, age 49–74 years). All participants underwent MRI and multi-voxel 1H-MRS examination within 3 days in admission. Six kinds of metabolites, such as creatine (Cr), N-acetyl aspartate/creatine (NAA/Cr), N-acetyl aspartate/choline (NAA/Cho), choline/creatine (Cho/Cr), lipid/creatine (LL/Cr), and myo-Inositol/creatine ratio (mI/Cr) were tested among the PD group and the control groups. Statistical analyses and correlation analyses were performed by using SPSS. The p < 0.05 was considered statistically significant. Results: Compared late PD group with a control group or early group, higher Cr ratio and lower NAA/Cr ratio were observed in the late PD group (p < 0.05). The mI/Cr in the late PD group was also lower than that in the early PD group (p < 0.05). Regarding the relationship between metabolites and NMS, Cho/Cr was higher in the sleep disorder group, whereas mI/Cr was lower in the gastrointestinal dysfunction group in comparison with the non-symptom groups. Moreover, Cr, Cho/Cr, mI/Cr, and LL/Cr were identified to have higher concentrations in the cognitive group in thalamus. Conclusions: Proton magnetic resonance spectroscopy is an advanced tool to quantify the metabolic changes in PD. Three biomarkers (Cr, NAA/Cr, and mI/Cr) were detected in the late stage of PD, suggesting that these markers might be potential to imply the progression of PD. In addition, subgroups analysis showed that MRS of thalamus is a sensitive region for the detection of cognitive decline in PD, and the alteration of neurochemicals (involving Cr, Cho, mI, and LL) may be promising biomarkers to predict cognitive decline in PD. [ABSTRACT FROM AUTHOR]

The traditional detection of telomerase activity is mainly based on the polymerase chain reaction (PCR), which has the disadvantages of being time-consuming and susceptible to interferences; thus, here, we propose a facile method for the fabrication of fluorescent tungsten oxide quantum dots (WOx QDs) and employ them for telomerase activity sensing. It is found that the fluorescence of WOx QDs can be significantly quenched by hemin based on the inner filter effect (IFE). However, in the presence of telomerase, the primer-DNA can be extended to generate repeating units of TTAGGG to form G-quadruplex and thus, hemin can be encapsulated to reduce its absorbance, resulting in decreased IFE and efficient fluorescence recovery of WOx QDs. Based on the fluorescence changes of IFE between hemin and WOx QDs, the telomerase activity within the range of 50–30 000 HeLa cells can be detected and the lowest detection amount can reach 17 cells. The method exhibits good versatility that can also be applied to telomerase detection in A549 and L929 cells. In addition, because of the good biocompatibility of the sensor, it can be used for the real-time monitoring of telomerase activity in living cells, thus showing great potential in tumor diagnosis and inhibitor drug screening. [ABSTRACT FROM AUTHOR]

A facile and sensitive method for the quantitative detection of telomerase and in situ imaging of intracellular telomerase is developed by using a graphene oxide (GO)-based fluorescent nanosensor. The nanosensor consists of a fluorescent DNA (P1) adsorbed on the GO surface. Here, GO serves not only as a fluorescence quencher but also as a carrier to successfully transport P1 into cancer cells as a signal reporter. P1 is a dye-labeled single-stranded DNA complementary to the telomeric repeated sequence, and initially the combination of P1 and GO exhibits minimal background fluorescence. When telomerase extends its repeat units of TTAGGG on the 3′-end of the primer-DNA, the fluorescence of P1 is subsequently recovered because the telomeric repeated sequence can hybridize with P1 and liberate it from the GO surface. This method enables the determination of telomerase activity down to 10 cells. For the in situ detection of telomerase, upon endocytosis of the P1/GO combinatorial probe into living cancer cells, the intracellular telomerase extends its primer to produce the telomeric repeated sequence and then turns on the fluorescence of P1, which can be directly monitored by confocal laser scanning microscopy. The feasibility of the assay is further investigated by treating with telomerase-related drugs, and the results demonstrate its potential in antitumor drug screening and cancer therapy evaluation. [ABSTRACT FROM AUTHOR]

Telomerase, as a potential biomarker for early cancer diagnostics and therapies, has attracted considerable interests concerning its detection and monitoring. Herein, we develop a novel method for sensitive detection of telomerase activity by designing a gold nanoparticles/graphene oxide (AuNPs/GO) probe. The AuNPs were functionalized with a telomerase substrate (TS) primer and a 6-carboxy-fluorescein (FAM)-modified complementary DNA (P1). In the absence of telomerase, P1 exists in the random-coiled conformation, and the fluorescence resonance energy transfer (FRET) from FAM to AuNPs and GO results in efficient fluorescence quenching. In the presence of telomerase, the multiple hybridization between TS extension products and P1 leads to the conformation transition of P1 from single-stranded DNA to double-stranded rigid structure, and thus the FRET process can be prevented with the efficient fluorescence recovery. The metal enhanced fluorescence (MEF) effect between FAM and AuNPs can further effectively enhance the fluorescence of FAM, and thus the sensitivity and specificity of telomerase detection can be remarkably improved. It is worth mentioning that the proposed strategy does not need to design complex hairpin structure and allows the measurement of telomerase activity in three crude cell extracts equivalent to 7 HeLa cells, 8 A549 cells and 8 L929 cells in 1 h. In addition, the present sensing platform can be applied to inhibitor screening, in situ telomerase imaging, and intracellular drug delivery. Image 1 • The metal enhanced fluorescence effect can be regulated to generate significant fluorescence enhancement. • Weak background fluorescence can be realized via efficient fluorescence resonance energy transfer. • Telomerase activity down to 7 HeLa cells can be sensitively detected. • The method facilitates cellular imaging, inhibitor screening and drug delivery. [ABSTRACT FROM AUTHOR]

Nephrotoxicity has long been the most severe and life-threatening side-effect of cisplatin, whose anticancer effect is therefore restricted. Previous pathological studies have shown that both renal cortex and medulla could be injured by cisplatin. Our TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling) assay results further uncovered that medulla subjected more severe injury than cortex. In order to depict the underlying metabolic mechanism of spatial difference in response to cisplatin, in the present study, mass spectrometry-based untargeted metabolomics approach was applied to profile renal cortex and medulla metabolites of rat after receiving a single dose of cisplatin (2.5, 5 or 10 mg/kg). Eventually, 53 and 55 differential metabolites in cortex and medulla were screened out, respectively. Random forest, orthogonal partial least squares-discriminant analysis and metabolic cumulative fold change analysis revealed that metabolic changes in medulla were more obviously dose-dependent than those in cortex, which confirmed the conclusion that medulla was more sensitive to cisplatin exposure. Furthermore, 29 intermediates were recognized as the most contributive metabolites for the sensitivity difference. Metabolic pathways interrupted by cisplatin mainly included amino acid, energy, lipid, pyrimidine, purine, and creatine metabolism. Our findings provide new insight into the mechanism study of cisplatin-induced nephrotoxicity. [ABSTRACT FROM AUTHOR]

Highlights • Cancer-associated telomerase activity can be detected with QDs-SA biosensor. • The detection limit of telomerase can be down to 13 Hela cells and 9 A549 cells. • The QDs-SA biosensor allows intracellular telomerase tracking and imaging. • Inhibitor screening can be realized in vitro and in vivo. Abstract In order to overcome the shortcomings of traditional methods for telomerase activity detection of time-consuming and susceptibility to interferences in cell extracts, here, we develop a semiconductor quantum dots-streptavidin conjugates (QDs-SA)-based biosensor for sensitive detection of telomerase activity. In the absence of telomerase, the aggregation and thus the fluorescence quenching of QDs-SA can be observed in buffer solution due to charge shielding effect. In the presence of telomerase and biotin-dATP, QDs-SA will bind to telomerase elongation products due to the high affinity between the biotin and streptavidin, protecting the QDs-SA from aggregation and retaining their strong fluorescence. This sensor exhibited good fluorescence responses toward telomerase activity from HeLa cells in the range of 40–1000 cells with a detection limit of 13 cells or A549 cells within the linear range of 20–500 cells with a detection limit of 9 cells. Furthermore, the sensor can be used to efficiently monitor the evolution of telomerase activity in living cells, demonstrating great potential in tumor diagnosis and inhibitor drug screening. [ABSTRACT FROM AUTHOR]

Determination of hydrogen peroxide (H 2 O 2 ) with high sensitivity and selectivity in living cells is a challenge for evaluating the diverse roles of H 2 O 2 in the physiological and pathological processes. In this work, we present novel surface enhanced Raman scattering (SERS) nanosensors, 4-carboxyphenylboronic acid (4-CA) modified gold nanoparticles (Au NPs/4-CA), for sensing H 2 O 2 in living cells. The nanosensors are based on that the H 2 O 2 -triggered oxidation reaction with the arylboronate on Au NPs would liberate the phenol, thus causing changes of the SERS spectra of the nanosensors. The results show the nanosensors feature higher selectivity for H 2 O 2 over other reactive oxygen species, abundant competing cellular thiols and biologically relevant species, as well as excellent sensitivity with a low detection limit of 80 nM, which fulfills the requirements for detection of H 2 O 2 in a biological system. In addition, the SERS nanosensors exhibit long term stability against time and pH, and high biocompatibility. More importantly, the presented nanosensors can be successfully used for monitoring changes of H 2 O 2 levels within living biological samples upon oxidative stress, which opens up new opportunities to study its cellular biochemistry. [ABSTRACT FROM AUTHOR]