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The development of messenger RNA (mRNA) vaccines and therapeutics necessitates the production of high-quality in vitro-transcribed mRNA drug substance with specific critical quality attributes (CQAs), which are closely tied to the uniformity of linear DNA template. The supercoiled plasmid DNA is the precursor to the linear DNA template, and the supercoiled DNA percentage is commonly regarded as a key in-process control (IPC) during the manufacturing of linear DNA template. In this study, we investigate the influence of supercoiled DNA percentage on key mRNA CQAs, including purity, capping efficiency, double-stranded RNA (dsRNA), and distribution of poly(A) tail. Our findings reveal a significant impact of supercoiled DNA percentage on mRNA purity and in vitro transcription yield. Notably, we observe that the impact on mRNA purity can be mitigated through oligo-dT chromatography, alleviating the tight range of DNA supercoiled percentage to some extent. Overall, this study provides valuable insights into IPC strategies for DNA template chemistry, manufacturing, and controls (CMC) and process development for mRNA drug substance.
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Real-time monitoring of broken rails in heavy haul railways is crucial for ensuring the safe operation of railway lines. U78CrV steel is a common material used for heavy haul line rails in China. In this study, the semi-analytical finite element (SAFE) method is employed to calculate the dispersion curves and modal shapes of ultrasonic guided waves in U78CrV heavy steel rails. Guided wave modes that are suitable for detecting rail cracks across the entire cross-section are selected based on the total energy of each mode and the vibration energy in the rail head, web, and foot. The excitation method for the chosen mode is determined by analyzing the energy distribution of the mode shape on the rail surface. The ultrasonic guided wave (UGW) signal in the rail is analyzed using ANSYS three-dimensional finite element simulation. The group velocity of the primary mode in the guided wave signal is obtained through continuous wavelet transform to confirm the existence of the selected mode. It is validated that the selected mode can be excited by examining the similarity between the vibration shapes of a specific rail section and all modal vibration shapes obtained through SAFE. Through simulation and field verification, the guided wave mode selected and excited in this study demonstrates good sensitivity to cracks at the rail head, web, and foot, and it can propagate over distances exceeding 1 km in the rail. By detecting the reflected signal of the selected mode or the degree of attenuation of the transmitted wave, long-distance monitoring of broken rails in heavy-haul railway tracks can be achieved.
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Multi-focus image fusion is a method to extend the depth of field to generate fully focused images. The effective detection of image focusing pixels and the optimization of image regions are the key to it. A method based on multidimensional structure and edge-guided correction (MSEGC) is proposed. The pixel-level focusing evaluation function is redesigned to preserve image details and non-texture regions. Edge-guided decision correction is used to suppress edge artifacts. With public data and semiconductor detection images for verification, the results show that compared with other methods, the objective evaluation is improved by 22-50%, providing better vision.
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Increasing evidence has indicated that microRNAs (miRNAs/miRs) play an important role in the occurrence and development of various types of cancer. The aim of the present study was to investigate the role and underlying molecular mechanisms of miR-195-5p in laryngeal cancer cell proliferation, migration and invasion. Reverse transcription-quantitative PCR (RT-qPCR) was performed to measure the expression levels of miR-195-5p in laryngeal carcinoma cell lines. The expression levels of miR-195-5p and E2F transcription factor 3 (E2F3) were modified by transfection with miR-195-5p mimics and pcDNA3.1-E2F3. A luciferase reporter assay was used to verify the association between miR-195a-5p and E2F3. Cell Counting Kit-8, cell wound healing and Transwell invasion assays were used to detect the biological functions of laryngeal cancer cells. The expression of epithelial-mesenchymal transition (EMT)-associated genes was evaluated by western blotting and RT-qPCR. The results revealed that the expression of miR-195-5p was decreased in laryngeal cancer cell lines. The overexpression of miR-195-5p inhibited the proliferation, migration, invasion and EMT of laryngeal cancer cells. Dual-luciferase reporter assays revealed that miR-195-5p could directly target E2F3 and that there was a negative association between them. E2F3 overexpression significantly attenuated the inhibitory effects of the overexpression of miR-195-5p on the proliferation, migration, invasion and EMT of laryngeal cancer cells. Collectively, the findings of the present study demonstrated that the overexpression of miR-195-5p significantly inhibited the progression of laryngeal cancer cells, and these effects may be mediated via the downregulation of the expression of E2F3.
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Metformin and berberine are often combined for treating diabetes. In the present study, we evaluated the drug-drug pharmacokinetic interaction between metformin and berberine after oral co-administration in vivo and the underlying mechanism. As revealed by comparison with the metformin-only group, berberine significantly decreased the maximum plasma concentration (Cmax), area under the curve from 0 to 4â¯h (AUC0-4h), and urinary and bile excretion, and increased the kidney tissue concentration of metformin in rats. The non-everted intestinal sac study showed that berberine inhibited the absorption of metformin, and in transfected Madin-Darby canine kidney (MDCK)-rat organic cation transporter 1 (MDCK-rOCT1), MDCK-rat organic cation transporter 2 (MDCK-rOCT2), and MDCK-rat multidrug and toxin extrusion 1 (MDCK-rMATE1) cells, berberine significantly inhibited metformin transport mediated by OCT1, OCT2, and MATE1 in a concentration-dependent manner with half-maximal inhibitory concentration (IC50) values of 18.8, 1.02, and 10.7⯵M, respectively. In contrast, co-administration of metformin increased the Cmax and AUC0-4h of berberine with no significant difference in pharmacokinetics parameters between co-administration and berberine-only groups. Furthermore, metformin increased kidney and liver concentrations and reduced the urinary and biliary excretion of berberine. Metformin (≥1 or ≥0.3â¯mM) decreased berberine transport in MDCK-rOCT1, MDCK-rOCT2, and MDCK-rMATE1 cells. However, metformin did not affect berberine concentration in MDCK-multidrug resistance protein 1 cells. These results suggest that the combination of metformin and berberine induced a pharmacokinetic interaction by cooperatively inhibiting OCT and MATE1-mediated transport.
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Antiportadores/metabolismo , Berberina/farmacocinética , Proteínas de Transporte de Catecolaminas en la Membrana Plasmática/metabolismo , Hipoglucemiantes/farmacocinética , Metformina/farmacocinética , Proteínas de Transporte de Catión Orgánico/metabolismo , Transportador 2 de Cátion Orgánico/metabolismo , Tejido Adiposo/metabolismo , Animales , Antiportadores/genética , Berberina/sangre , Proteínas de Transporte de Catecolaminas en la Membrana Plasmática/genética , Perros , Interacciones Farmacológicas , Femenino , Hipoglucemiantes/sangre , Mucosa Intestinal/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Células de Riñón Canino Madin Darby , Masculino , Metformina/sangre , Músculo Esquelético/metabolismo , Proteínas de Transporte de Catión Orgánico/genética , Transportador 2 de Cátion Orgánico/genética , Ratas Sprague-DawleyRESUMEN
As the irreversibility of hair cell loss in mammals is among the main reasons giving rise to permanent hearing loss, studies have been focused on the development of biological technologies to generate new hair cells as a means of replacing lost hair cells. Bone marrow-derived mesenchymal stem cells (BMSCs) possess the capacity to differentiate into hair cell-like cells, and may find applications in the regeneration of mammalian cochlear hair cells. In order to efficiently induce BMSCs into hair cells, alginate microcapsules co-delivering rat bone marrow-derived mesenchymal stem cells (rBMSCs) and anti-EGF monoclonal antibody (mAb) were developed to examine the feasibility of differentiating rBMSC into hair cell-likes cells in vitro and in vivo by taking advantage of epidermal growth factor (EGF) ligands. In vitro analysis showed that anti-EGF mAbs bonded with exogenous EGF ligands activated the EGF receptors on rBMSCs, enhancing the expression of myosin 7a (a hair cell marker) and Notch1 (supporting cell marker) via the EGFR/Ras/Raf/ERK1/2 signal pathway. In in vivo experiments, alginate microcapsules loaded with rBMSCs (2 × 106 cells per microcapsule) together with Iso mAbs or anti-EGF mAbs were grafted into guinea pig cochlea. After 6 weeks of treatment, immunofluorescence analyses indicated that the rBMSCs embedded into anti-EGF microcapsules were more efficiently transformed into hair cells compared with the group with Iso mAb microcapsules and displayed an ordered arrangement in Reissner's membranes. The results highlighted the significance of engineering the microenvironment of stem cells for hair cell differentiation, and particularly the advantage of hair cell differentiation of rBMSCs by recruiting host EGF ligands via tethered mAbs. In conclusion, this strategy of co-embedding rBMSCs and anti-EGF mAb in alginate microcapsules is a promising modality for the regeneration of hair cell-like cells.
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This study observes the therapeutic detoxification of quercetin, a well-known flavonoid, against carbon tetrachloride (CCl4) induced acute liver injury in vivo and explores its mechanism. Quercetin decreased CCl4-increased serum activities of alanine and aspartate aminotransferases (ALT/AST) when orally taken 30 min after CCl4 intoxication. The results of a histological evaluation further evidenced the ability of quercetin to protect against CCl4-induced liver injury. Quercetin decreased the CCl4-increased malondialdehyde (MDA) and reduced the glutathione (GSH) amounts in the liver. It also reduced the enhanced immunohistochemical staining of the 4-hydroxynonenal (4-HNE) in the liver induced by CCl4. Peroxiredoxin (Prx) 1, 2, 3, 5, 6, thioredoxin reductase 1 and 2 (TrxR1/2), thioredoxin 1 and 2 (Trx1/2), nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) all play critical roles in maintaining cellular redox homeostasis. Real-time polymerase chain reaction (PCR) results demonstrated that quercetin reversed the decreased mRNA expression of all those genes induced by CCl4. In conclusion, our results demonstrate that quercetin ameliorates CCl4-induced acute liver injury in vivo via alleviating oxidative stress injuries when orally taken after CCl4 intoxication. This protection may be caused by the elevation of the antioxidant capacity induced by quercetin.