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Compliant mechanism work based on the elasticity of material, dimension of the compliant mechanisms and the shape of flexure hinge. In order to larger workspace, most published works use theoretical models to determine the displacement amplification of the mechanical systems, which is very difficult to do. A simpler method that can still achieve efficiency while designing a mechanism with high displacement gain and low stress that ensures a stable working structure is to use combined grey relational analysis Taguchi method is based on the results of finite element analysis in ANSYS. To do this, first select the design variables for the symmetric differential lever displacement amplifier model. Next step, use Minitab software to design 27 cases. Then use SolidWorks to design 27 models of symmetrical differential displacement amplifier. Next to finite element analysis in ANSYS to obtain displacements and stresses of the symmetrical differential lever compliant mechanism with circular flexure hinge. The results obtained from the finite element model are used for optimization by grey relationship analysis combined with the Taguchi method. The FEM results indicated that the designed variables significantly affected on the displacement and stress of the symmetrical differential lever displacement magnification compliant mechanism. The problem was also confirmed by grey relational analysis with Taguchi method. The predicted and optimal values of the displacement were 0.11276 mm and 0.1179 mm, with error of 4.36%. The input displacement was 0.01 mm, while the displacement magnification ratio was 11.79 times. The results verified by decision-making criteria: TOPSIS method, MOORA method and EDAS method. [ABSTRACT FROM AUTHOR]

Abstract In this work, the friction characteristics of single-layer MoS2 prepared with chemical vapor deposition (CVD) at three different temperatures were quantitatively investigated and compared to those of single-layer MoS2 prepared using mechanical exfoliation. The surface and crystalline qualities of the MoS2 specimens were characterized using an optical microscope, atomic force microscope (AFM), and Raman spectroscopy. The surfaces of the MoS2 specimens were generally flat and smooth. However, the Raman data showed that the crystalline qualities of CVD-grown single-layer MoS2 at 800 °C and 850 °C were relatively similar to those of mechanically exfoliated MoS2 whereas the crystalline quality of the CVD-grown single-layer MoS2 at 900 °C was lower. The CVD-grown single-layer MoS2 exhibited higher friction than mechanically exfoliated single-layer MoS2, which might be related to the crystalline imperfections in the CVD-grown MoS2. In addition, the friction of CVD-grown single-layer MoS2 increased as the CVD growth temperature increased. In terms of tribological properties, 800 °C was the optimal temperature for the CVD process used in this work. Furthermore, it was observed that the friction at the grain boundary was significantly larger than that at the grain, potentially due to defects at the grain boundary. This result indicates that the temperature used during CVD should be optimized considering the grain size to achieve low friction characteristics. The outcomes of this work will be useful for understanding the intrinsic friction characteristics of single-layer MoS2 and elucidating the feasibility of single-layer MoS2 as protective or lubricant layers for micro- and nano-devices.

Nghiên cứu nhằm đánh giá hệ vi sinh vật phân giải lân trên đất phù sa trung tính (huyện Gia Lâm, Hà Nội) và đất phù sa gley (huyện Tiên Lữ, tỉnh Hưng Yên) thuộc hệ thống sông Hồng chuyên trồng lúa (2 vụ/năm) tại thời điểm lúa đang làm đòng. Kết quả phân lập cho thấy, có sự xuất hiện của nhóm vi khuẩn, xạ khuẩn phân giải lân trong các mẫu đất nghiên cứu nhưng hoàn toàn không có mặt của nấm mốc. Nhìn chung, đất phù sa trung tính có mật độ vi sinh vật phân giải lân cao hơn nhưng kém phong phú hơn về số lượng chủng so với đất phù sa gley. Mức độ đa dạng của các chủng vi sinh vật không giống nhau giữa 2 loại đất, thậm chí giữa các mẫu khác nhau trong cùng một loại đất. Có 4 chủng vi khuẩn phân giải lân phổ biến trong đất phù sa trung tính, mật độ dao động từ 15,5-22,9 x104 CFU/g đất; trong khi đó, trên đất phù sa gley phổ biến 4 chủng vi khuẩn và 1 chủng xạ khuẩn, mật độ biến động từ 2,3-17,3 x104 CFU/g đất. Trên cả 2 loại đất, mật độ vi sinh vật phân giải lân vô cơ chiếm ưu thế hơn so với hữu cơ. Tuy nhiên, so với vi sinh vật tổng số, mật độ các nhóm vi sinh vật phân giải lân đều rất thấp, chiếm chưa tới 1% mỗi nhóm. Bên cạnh đó, hoạt tính phân giải lân của chúng không cao, hàm lượng PO43- giải phóng dao động từ 0,70-5,66 mg/l đối với lân dạng Tricalcium phosphate và từ 0,0-1,83 mg/l đối với lân dạng Lecithine.

Collagenases are responsible for collagen degradation, resulting in shrimp muscle softening after death. In this study, biochemical characteristics of collagenases purified from hepatopancreas (CPH) and muscle (CPM) of Litopenaeus vannamei were comparatively investigated. Changes of enzyme activity in shrimp hepatopancreas and muscle presented totally different tendencies, which decreased and increased respectively. Also, the key collagenases in different shrimp body parts were different. The CPH was identified as a highly metal-dependent serine proteinase, while the CPM was identified as a Ba 2+ -dependent metalloproteinase with a maximum activity at 50 °C and pH of 7.0. In terms of degradation behaviors, both CPH and CPM could hydrolyze type I collagen. However, because of diversified cleavage sites and higher efficiency, the CPM was able to degrade collagen more completely. Hence, these findings clarified the collagen degradation mechanism from a new perspective, providing theoretical basis for shrimp texture maintenance., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled Collagenases from hepatopancreas and muscle of Litopenaeus vannamei: Purification, characterization and comparison of their behaviors in collagen degradation., (Copyright © 2025 Elsevier Ltd. All rights reserved.)

Despite the discovery of numerous oncogenes in colorectal cancer (CRC), the development of associated drugs is limited, posing a significant challenge for CRC treatment. Identification of novel druggable targets is therefore crucial for the therapeutic development of CRC. Here, we report the first investigation on therapeutics targeting the potent oncogene NUCKS1 to suppress cancer progression. NUCKS1-orientated bioinformatics screening of NUCKS1 inhibitors from our library of tRNA fragments originated from medicinal plants identified tRF-T36, a 5' tRNA fragment of tRNA Asn(GUU) of Chinese yew ( Taxus chinensis ), exhibiting stronger inhibitory effects than taxol against CRC progression. Mechanistically, tRF-T36 binds directly to the 3' UTR of NUCKS1 mRNA to downregulate its expressions via RNAi pathway. High-throughput RNA sequencing indicated that the downregulated NUCKS1 induced by tRF-T36 further inhibits PI3K/Akt pathway, as verified by the significantly efficacy decrease of tRF-T36 mimic in co-treatment with 740Y-P, an agonist of PI3K/Akt pathway. Collectively, our findings emphasize the importance of NUCKS1 as a promising druggable target for CRC. Furthermore, the present study provides the first siRNA sequence, tRF-T36 mimic, as small RNA drug candidate, thereby shedding light on CRC therapeutics., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Matrix metalloproteinases (MMPs) play critical roles in the degradation of collagens, while their mechanism remains unclear. In the present study, the involvement of matrix metalloproteinases (MMPs) in collagen degradation of sea bass muscle during cold storage was explored. Immunohistochemical staining results showed significant degradation of type I collagen in the connective tissue of muscle endomysium during cold storage, thus affecting the muscle structural integrity and quality. Western blot analysis revealed an increment in the α1 chain and a decrease in the β and γ chains of type I collagen. Immunofluorescence staining showed that MMP-2, MMP-9, and MMP-13 were distributed in the endomysium surrounding the muscle fibers. Additionally, the catalytic domains of MMP-2, MMP-9, and MMP-13 with biological activities were successfully expressed. The degradation trend of type I collagen by MMPs under 4 °C was similar to that of muscle collagen during cold storage, suggesting that the degradation of type I collagen was attributed to the cooperative action of the MMPs. In conclusion, our study elucidated that the MMPs-engaged degradation of type I collagen is quite possibly the leading cause of sea bass muscle softening during cold storage.

X-ray images typically contain complex background information and abundant small objects, posing significant challenges for object detection in security tasks. Most existing object detection methods rely on complex networks and high computational costs, which poses a challenge to implement lightweight models. This article proposes Fine-YOLO to achieve rapid and accurate detection in the security domain. First, a low-parameter feature aggregation (LPFA) structure is designed for the backbone feature network of YOLOv7 to enhance its ability to learn more information with a lighter structure. Second, a high-density feature aggregation (HDFA) structure is proposed to solve the problem of loss of local details and deep location information caused by the necked feature fusion network in YOLOv7-Tiny-SiLU, connecting cross-level features through max-pooling. Third, the Normalized Wasserstein Distance (NWD) method is employed to alleviate the convergence complexity resulting from the extreme sensitivity of bounding box regression to small objects. The proposed Fine-YOLO model is evaluated on the EDS dataset, achieving a detection accuracy of 58.3% with only 16.1 M parameters. In addition, an auxiliary validation is performed on the NEU-DET dataset, the detection accuracy reaches 73.1%. Experimental results show that Fine-YOLO is not only suitable for security, but can also be extended to other inspection areas.

Polyphenol oxidase (PPO) plays a critical role in decrement of shrimp quality. To obtain active PPO and elucidate its enzymatic properties, PPO from Litopenaeus vannamei (Lv-PPO) was cloned, expressed in E. coli and purified by affinity column chromatography. The Lv-PPO gene was 2076 bp in length encoding 691 amino acids. The recombinant Lv-PPO (rLv-PPO) with a molecular mass of ∼85.0 kDa was successfully expressed and its sequence was verified by LC-MS/MS. rLv-PPO was biologically active with an optimal temperature of 40℃ and an optimal pH of 6.0. Metal ions Cu 2+ and Zn 2+ altered the activity of rLv-PPO by influencing its secondary and tertiary structures. rLv-PPO showed catalytic activity towards l-Dopa and catechol. A specific polyclonal antibody against rLv-PPO was prepared. Western blot analysis revealed that PPO levels were highest in hemolymph, followed by telson, carapace, and eyestalk. Expression of rLv-PPO will assist future studies on the mechanism in shrimp melanosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Objectives: This study addresses the bioavailability challenges associated with oral nicotinamide mononucleotide (NMN) administration by introducing an innovative NMN formulation incorporated with hydroxyapatite (NMN-HAP)., Methods: The NMN-HAP was developed using a wet chemical precipitation and physical adsorption method. To assess its superiority over conventional free NMN, we examined NMN, nicotinamide adenine dinucleotide (NAD+), and nicotinamide riboside (NR) levels in mouse plasma and tissues following oral administration of NMN-HAP., Key Findings: NMN-HAP nanoparticles demonstrated a rod-shaped morphology, with an average size of ~50 nm, along with encapsulation efficiency and drug loading capacity exceeding 40%. In vitro, drug release results indicated that NMN-HAP exhibited significantly lower release compared with free NMN. In vivo studies showed that NMN-HAP extended circulation time, improved bioavailability compared with free NMN, and elevated plasma levels of NMN, NAD+, and NR. Moreover, NMN-HAP administration displayed tissue-specific distribution with a substantial accumulation of NMN, NAD+, and NR in the brain and liver., Conclusion: NMN-HAP represents an ideal formulation for enhancing NMN bioavailability, enabling tissue-specific delivery, and ultimately elevating in vivo NAD+ levels. Considering HAP's biocompatible nature and versatile characteristics, we anticipate that this system has significant potential for various future applications., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Royal Pharmaceutical Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Many factors are responsible for the diminished quality of shrimp during cold storage, while the role of collagen has rarely been studied. This study therefore investigated the relationship between collagen degradation and changes of textural properties of Pacific white shrimp, and its hydrolysis by endogenous proteinases. The textural properties of shrimp decreased gradually along with disruption of shrimp muscle tissues, and the chewiness property of shrimp muscle showed a linear relationship with collagen contents in muscle during 6-day-storage at 4 °C. Pepsin-solubilized collagen in shrimp muscle consisted of one α1 chain and two α2 chains, revealing a typical tripeptide sequence (i.e., Gly-X-Y) in their molecules. In addition, collagen could be hydrolyzed by crude endogenous proteinases extracted from shrimp hepatopancreas, and serine proteinase plays a critical role in the process. These findings strongly suggested that the quality reduction of shrimp during cold storage is closely associated with collagen degradation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Ganoderma lucidum (Ganoderma) is a famous Chinese herbal medicine which has been used clinically for thousands of years in China. Despite numerous studies on triterpenes and polysaccharides, the bioactivity of RNAs abundant in Ganoderma remains unknown. Here, based on LC-MS techniques, dihydrouracil, 5-methyluridine (m 5 U) and pseudouridine were identified at position 19, 52 and 53 of a new tRNA Ile(GAU) which was isolated as the most abundant tRNA species in Ganoderma, and is the first purified tRNA from fungus. Cytotoxic screening of tRNA-half (t-half) and tRNA fragment (tRF) derived from this tRNA, as well as their mimics (t-half or tRF as antisense strand), demonstrated that the double-stranded form, i.e., tRF and t-halve mimics, exhibited stronger cytotoxicity than their single-stranded form, and the cytotoxicity of t-half mimic is significantly stronger than that of tRF mimic. Notably, the cytotoxicity of 3'-t-half mimic is not only much more potent than that of taxol, but also is much more potent than that of ganoderic acids, the major bioactive components in Ganoderma. Furthermore, 3'-t-half mimic_M2 (m 5 U modified) exhibited significantly stronger cytotoxicity than unmodified 3'-t-half mimic, which is consistent with the computational simulation showing that m 5 U modification enhances the stability of the tertiary structure of 3'-t-half mimic. Overall, the present study not only indicates t-halves are bioactive components in Ganoderma which should not be neglected, but also reveals an important role of post-transcriptional modification on tRNA in its fragments' cytotoxicity against cancer cells, which benefits the design and development of RNAi drugs from natural resource., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Objective: To present a multifaceted approach to ophthalmology undergraduate medical education and to assess the efficacy of an eye dissection laboratory in enhancing medical student learning., Design: Curriculum review, validation, and student feedback evaluations., Participants: Year 2 medical students enrolled in the University of Toronto's Doctor of Medicine Program., Methods: Student feedback evaluations were compiled from the University of Toronto undergraduate medical education student surveys before 2012-2016 and following introduction of the redesigned foundations ophthalmology curriculum at the University of Toronto (2017-2018). Students who participated in the Eye Dissection Lab as part of the newly designed curriculum completed the pre- and postsession satisfaction and overall interest in ophthalmology questionnaires and a knowledge-based test., Results: Analysis of 1640 student evaluations demonstrated an increase in ophthalmology curriculum rating following the launch of the foundations ophthalmology curriculum (p = 0.015). Among the 335 students who completed the eye dissection lab, there was a significant increase in the average scores for the satisfaction questionnaire, knowledge-based test, and level of interest in the field of ophthalmology from before and after the session, with improvements in scores noted in 91%, 42%, and 36% of the educational parameters of the participants, respectively (p < 0.001)., Conclusions: The newly designed foundations ophthalmology curriculum and the eye dissection lab at the University of Toronto serve as effective means for enhancing ophthalmology teaching in medical schools across Canada., (Copyright © 2021 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Traditional Chinese medicines (TCMs) have been widely used for treating ischemic heart disease (IHD), and secondary metabolites are generally regarded as their pharmacologically active components. However, the effects of nucleic acids in TCMs remain unclear. We reported for the first time that a 22-mer double-strand RNA consisting of HC83 (a tRNA-derived fragment [tRF] from the 3' end of tRNA Gln(UUG) of ginseng) and its complementary sequence significantly promoted H9c2 cell survival after hypoxia/reoxygenation (H/R) in vitro . HC83&#95;mimic could also significantly improve cardiac function by maintaining both cytoskeleton integrity and mitochondrial function of cardiomyocytes. Further in vivo investigations revealed that HC83&#95;mimic is more potent than metoprolol by >500-fold against myocardial ischemia/reperfusion (MI/R) injury. In-depth studies revealed that HC83 directly downregulated a lncRNA known as myocardial infarction-associated transcript (MIAT) that led to a subsequent upregulation of VEGFA expression. These findings provided the first evidence that TCM-derived tRFs can exert miRNA-like functions in mammalian systems, therefore supporting the idea that TCM-derived tRFs are promising RNA drug candidates shown to have extraordinarily potent effects. In summary, this study provides a novel strategy not only for discovering pharmacologically active tRFs from TCMs but also for efficiently exploring new therapeutic targets for various diseases., Competing Interests: The authors declare no competing interests., (© 2022 The Authors.)

tRNAs purified from non-pathogenic Escherichia coli strains (NPECSs) possess cytotoxic properties on colorectal cancer cells. In the present study, the bioactivity of tRNA halves and tRNA fragments (tRFs) derived from NPECSs are investigated for their anticancer potential. Both the tRNA halves and tRF mimics studied exhibited significant cytotoxicity on colorectal cancer cells, with the latter being more effective, suggesting that tRFs may be important contributors to the bioactivities of tRNAs derived from the gut microbiota. Through high-throughput screening, the EC83 mimic, a double-strand RNA with a 22-nucleotide (nt) 5'-tRF derived from tRNA-Leu(CAA) as an antisense chain, was identified as the one with the highest potency (50% inhibitory concentration [IC 50 ] = 52 nM). Structure-activity investigations revealed that 2'- O -methylation of the ribose of guanosine (Gm) may enhance the cytotoxic effects of the EC83 mimic via increasing the stability of its tertiary structure, which is consistent with the results of in vivo investigations showing that the EC83-M2 mimic (Gm modified) exhibited stronger antitumor activity against both HCT-8 and LoVo xenografts. Consistently, 4-thiouridine modification does not. This provides the first evidence that the bioactivity of tRF mimics would be impacted by chemical modifications. Furthermore, the present study provides the first evidence to suggest that novel tRNA fragments derived from the gut microbiota may possess anticancer properties and have the potential to be potent and selective therapeutic molecules. IMPORTANCE While the gut microbiota has been increasingly recognized to be of vital importance for human health and disease, the current literature shows that there is a lack of attention given to non-pathogenic Escherichia coli strains. Moreover, the biological activities of tRNA fragments (tRFs) derived from bacteria have rarely been investigated. The findings from this study revealed tRFs as a new class of bioactive constituents derived from gut microorganisms, suggesting that studies on biological functional molecules in the intestinal microbiota should not neglect tRFs. Research on tRFs would play an important role in the biological research of gut microorganisms, including bacterium-bacterium interactions, the gut-brain axis, and the gut-liver axis, etc. Furthermore, the guidance on the rational design of tRF therapeutics provided in this study indicates that further investigations should pay more attention to these therapeutics from probiotics. The innovative drug research of tRFs as potent druggable RNA molecules derived from intestinal microorganisms would open a new area in biomedical sciences.

Drug discovery from plants usually focuses on small molecules rather than such biological macromolecules as RNAs. Although plant transfer RNA (tRNA)-derived fragment (tRF) has been associated with the developmental and defense mechanisms in plants, its regulatory role in mammals remains unclear. By employing a novel reverse small interfering RNA (siRNA) screening strategy, we show that a tRF mimic (antisense derived from the 5' end of tRNA His(GUG) of Chinese yew) exhibits comparable anti-cancer activity with that of taxol on ovarian cancer A2780 cells, with a 16-fold lower dosage than that of taxol. A dual-luciferase reporter assay revealed that tRF-T11 directly targets the 3' UTR of oncogene TRPA1 mRNA. Furthermore, an Argonaute-RNA immunoprecipitation (AGO-RIP) assay demonstrated that tRF-T11 can interact with AGO2 to suppress TRPA1 via an RNAi pathway. This study uncovers a new role of plant-derived tRFs in regulating endogenous genes. This holds great promise for exploiting novel RNA drugs derived from nature and sheds light on the discovery of unknown molecular targets of therapeutics., Competing Interests: The authors declare no competing interests., (© 2022 The Author(s).)

Background: Cholangiocarcinoma is a devastating disease with a 2% 5-year survival if the disease has spread outside the liver. The enzyme aspartate beta-hydroxylase (ASPH) has been demonstrated to be highly expressed in cholangiocarcinoma but not in normal bile ducts and found to stimulate tumor cell migration. In addition, it was found that targeting ASPH inhibits cholangiocarcinoma malignant progression. However, it is not clear whether targeting ASPH with the small molecule inhibitor MO-I-1182 suppresses cholangiocarcinoma metastasis. The current study aims to study the efficacy of MO-I-1182 in suppressing cholangiocarcinoma metastasis., Methods: The analysis was performed in vitro and in vivo with a preclinical animal model by using molecular and biochemical strategies to regulate ASPH expression and function., Results: Knockdown of ASPH substantially inhibited cell migration and invasion in two human cholangiocarcinoma cell lines. Targeting ASPH with a small molecule inhibitor suppressed cholangiocarcinoma progression. Molecular mechanism studies demonstrated that knockdown of ASPH subsequently suppressed protein levels of the matrix metalloproteinases. The ASPH knockdown experiments suggest that this enzyme may modulate cholangiocarcinoma metastasis by regulating matrix metalloproteinases expression. Furthermore, using an ASPH inhibitor in a rat cholangiocarcinoma intrahepatic model established with BED-Neu-CL#24 cholangiocarcinoma cells, it was found that targeting ASPH inhibited intrahepatic cholangiocarcinoma metastasis and downstream expression of the matrix metalloproteinases., Conclusion: ASPH may modulate cholangiocarcinoma metastasis via matrix metalloproteinases expression. Taken together, targeting ASPH function may inhibit intrahepatic cholangiocarcinoma metastasis and improve survival.

Background: Tumor-associated antigens (TAAs) can be targeted in cancer therapy. We previously identified a monoclonal antibody (mAb) 12C7, which presented anti-tumor activity in lung cancer stem cells (LCSCs). Here, we aimed to identify the target antigen for 12C7 and confirm its role in LCSCs., Methods: Immunofluorescence was used for antigen localization. After targeted antigen purification by electrophoresis and immunoblot, the antigen was identified by LC-MALDI-TOF/TOF mass spectrometry, immunofluorescence, and immunoprecipitation. The overexpression or silence of ENO1 was induced by lentiviral transduction. Self-renewal, growth, and invasion of LCSCs were evaluated by sphere formation, colony formation, and invasion assay, respectively. High-throughput transcriptome sequencing (RNA-seq) and bioinformatics analysis were performed to analyze downstream targets and pathways of targeted antigen., Results: Targeted antigen showed a surface antigen expression pattern, and the 43-55 kDa protein band was identified as α-enolase (ENO1). Self-renewal, growth, and invasion abilities of LCSCs were remarkably inhibited by ENO1 downregulation, while enhanced by ENO1 upregulation. RNA-seq and bioinformatics analysis eventually screened 4 self-renewal-related and 6 invasion-related differentially expressed genes. GSEA analysis and qRT-PCR verified that ENO1 regulated self-renewal, invasion-related genes, and pathways. KEGG pathway analysis and immunoblot demonstrated that ENO1 inactivated AMPK pathway and activated mTOR pathway in LCSCs., Conclusions: ENO1 is identified as a targeted antigen of mAb 12C7 and plays a pivotal role in facilitating self-renewal, growth, and invasion of LCSCs. These findings provide a potent therapeutic target for the stem cell therapy for lung cancer and have potential to improve the anti-tumor activity of 12C7.

Transfer RNAs (tRNAs) are the most heavily modified RNA species. Liquid chromatography coupled with mass spectrometry (LC-MS/MS) is a powerful tool for characterizing tRNA modifications, which involves pretreating tRNAs with base-specific ribonucleases to produce smaller oligonucleotides amenable to MS. However, the quality and quantity of products from base-specific digestions are severely impacted by the base composition of tRNAs. This often leads to a loss of sequence information. Here, we report a method for the full-range profiling of tRNA modifications at single-base resolution by combining site-specific RNase H digestion with the LC-MS/MS and RNA-seq techniques. The key steps were designed to generate high-quality products of optimal lengths and ionization properties. A linear correlation between collision energies and the m/z of oligonucleotides significantly improved the information content of collision-induced dissociation (CID) spectra. False positives were eliminated by up to 95% using novel inclusion criteria for collecting a census of modifications. This method is illustrated by the mapping of mouse mitochondrial tRNA His(GUG) and tRNA Val(UAC) , which were hitherto not investigated. The identities and locations of the five species of modifications on these tRNAs were fully characterized. This approach is universally applicable to any tRNA species and provides an experimentally realizable pathway to the de novo sequencing of post-transcriptionally modified tRNAs with high sequence coverage.

Background: Acute respiratory infections (ARIs) remain a significant public threat with high morbidity and mortality worldwide; viruses are significant pathogens that cause ARIs. This study was conducted to better understand the epidemiological characteristics of respiratory viruses circulating in southern China., Methods: We collected 22,680 respiratory samples from ARI patients in 18 hospitals in southern China during 2009-2018; seven common respiratory viruses including Flu, RSV, PIV, hMPV, ADV, HCoV, and HBoV were screened using in-house real-time PCR., Results: Of all samples, 9760 ARI cases (9760/22680, 43.03%) tested positive for the seven common respiratory viruses. The most detected virus was Flu (14.15%), followed by RSV (10.33%) and PIV (5.43%); Flu-A, PIV3, and HCoV-OC43 were the predominant subtypes. Although most of the viruses were detected in male inpatients, Flu was more likely detected in female outpatients. Flu infection was more likely to cause URTI (upper respiratory tract infection), whereas RSV infection was more likely to cause pneumonia and bronchitis. The prevalence of Flu was particularly high in 2009. The epidemic level was found notably high in 2014-2018 for RSV, in 2016-2018 for PIV, in the summer of 2018 for ADV, in the summer of 2016 and winter of 2018 for HCoV, and in the summer of 2011 and autumn of 2018 for HBoV. The co-detection rate of the seven viruses was 4.70%; RSV, PIV, and Flu were the most commonly co-detected viruses., Conclusions: This work demonstrates the epidemiological characteristics of seven common respiratory viruses in ARI patients in southern China., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Human respiratory syncytial virus (RSV) is one of the most important pathogens that cause acute respiratory infections in children and immunocompromised adults. This work was conducted to understand the epidemiological and phylogenetic features of RSV in southern China during 2011-2016., Methods: A total of 16 024 nasopharyngeal swabs were collected from patients with respiratory infections in 14 hospitals, and screened for RSV and seven other respiratory viruses using real-time PCR. Six hundred and twenty-three RSV-positive samples from 13 hospitals were further analyzed for subtypes. G gene sequencing and phylogenetic analysis were performed based on 46 RSV-A and 15 RSV-B strains., Results: RSV was detected in 9.5% of the 16 024 specimens, the highest among the eight respiratory viruses screened. Most of these specimens came from inpatients and children under 3 years of age. The incidence of RSV-A (9.4%) was higher than that of RSV-B (4.4%) in children (<15 years), but not in adults (0.64% vs. 0.58%). A 2-year RSV-A dominance followed by a 1-year RSV-B dominance pattern was found. The co-detection rate of RSV was 25.1%. The main prevalent genotypes were NA1, ON1, and BA9. The prevalent RSV-A genotype in 2011-2012 was NA1, close to Chongqing and Brazil, but a new Hong Kong ON1 genotype was introduced and became the prevalent genotype in Guangzhou in 2014-2015. Deduced amino acid sequence analysis confirmed the ongoing evolution and a high selection pressure of RSV-A and B strains, especially in RSV-A ON1 and NA1 genotypes., Conclusions: This study demonstrated the molecular epidemiological characteristics of RSV in patients with respiratory infections in southern China., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Transfer RNAs (tRNAs) are the most abundant class in small non-coding RNAs which have been proved to be pharmacologically active. In the present study, we evaluated the potential anticancer activities of tRNAs from Escherichia coli MRE 600 to investigate the relationship between non-pathogenic Escherichia coli strain and colorectal cancer. To purify individual tRNAs, we firstly developed a two-dimensional liquid chromatography (2D-LC) and successfully obtained two pure tRNAs. Nuclease mediated base-specific digestions coupled with UHPLC-MS/MS techniques led to an identification of these two tRNAs as tRNA-Val(UAC) and tRNA-Leu(CAG) with typical cloverleaf-like secondary structure. MTT assay demonstrated that both tRNA-1 and tRNA-2 exhibit strong cytotoxicity with IC 50 of 113.0 nM and 124.8 nM on HCT-8 cells in a dose-dependent manner. Further clonogenic assay revealed that the purified tRNAs exhibit significant inhibition in colony formation with survival percentage of 79.0 ± 1.6 and 71.2 ± 2.2 at the concentration of 100 nM. These findings provided evidences of anticancer activities of tRNAs from non-pathogenic Escherichia coli strain, indicating that the pharmacological effects of these neglected biomacromolecules from microorganisms should be emphasized. This study put new insights into the therapeutic effects of intestinal microorganism on human diseases, therefore broadened our knowledge of the biological functions of gut microbiota., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: MCOLN1 (mucolipin subfamily, member 1) was first identified as an autophagic regulator, which was essential for efficient fusion of both autophagosomes and late endosomes with lysosomes. This study is aimed at investigating the role of MCOLN1 in the development of pancreatic ductal adenocarcinoma (PDAC)., Methods: Immunohistochemistry (IHC) assay was conducted to evaluate the expression level of MCOLN1 in 82 human PDAC tumor tissues. Overall survival (OS) and recurrence-free survival (RFS) analysis was performed to assess the prognosis of patients. Colony formation and MTT assays [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide] were performed to measure the proliferation capacity of tumor cells. The expression level of related genes was measured by RT-PCR (reverse transcription polymerase chain reaction) and western blot assays. The animal model was used to examine the effects of indicated protein on tumorigenesis in vivo., Results: The results of IHC showed that a high level of MCOLN1 expression was associated with the poor clinical characteristics of PDAC patients. OS and RFS were significantly worse in patients with high MCOLN1 expression. Silencing of MCOLN1 dramatically blocked the proliferation of PDAC cells. Mechanism studies confirmed that knockdown of MCOLN1 decreased the expression of Ki67 and PCNA (proliferating cell nuclear antigen), two markers of cell proliferation. In vivo, MCOILN1 depletion reduced the formation and growth of tumors in mice., Conclusion: The high level of MCOLN1 expression was associated with poor clinical outcomes of PDAC patients. MCOLN1 ablation could inhibit PDAC proliferation of both in vitro and in vivo, which provide a new insight and novel therapeutic target for the treatment of PDAC., Competing Interests: The authors have declared that no competing financial interest exists.

Although current quetiapine labeling recommends that its dosage should be lowered 6-fold when coadministered with strong cytochrome P450 (CYP)3A inhibitors, a reported case of coma in a patient receiving quetiapine with lopinavir and ritonavir prompted the reevaluation of labeling recommendations for the dosing of quetiapine when coadministered with human immunodeficiency virus (HIV) protease inhibitors. Literature and database (FDA Adverse Event Reporting System and United States Symphony Health Solutions' Integrated Dataverse Database) searches allowed us to identify cases of coma and related adverse events involving the coadministration of quetiapine and HIV protease inhibitors and to estimate the frequency of concomitant use. Literature review and physiologically based pharmacokinetic modeling allowed us to estimate the potential for CYP3A inhibition to contribute to adverse events related to HIV protease inhibitor-quetiapine coadministration. We identified excess sedation following coadministration of quetiapine and an HIV protease inhibitor in 3 reports without obvious confounders. In prescription claims data, 0.4% of quetiapine patients were dispensed a concurrent ritonavir prescription. The quetiapine dose was not reduced on ritonavir initiation in 90% of therapy episodes. Available data indicate to us that all HIV protease inhibitors combined with ritonavir are likely to be strong CYP3A inhibitors. We predicted that ritonavir would increase quetiapine exposure comparable to the strong CYP3A inhibitor ketoconazole. The current dosing recommendations for use of quetiapine with strong CYP3A inhibitors (ie, 6-fold lower quetiapine dose) are appropriate and should be followed when quetiapine is coadministered with HIV protease inhibitors., (© Published 2018. This article is a U.S. Government work and is in the public domain in the USA.)

The 5-hydroxymethylcytosine (5hmc) is a newly identified epigenetic modification thought to be regulated by the TET family of proteins. Little information is available about how ethanol consumption may modulate 5hmC formation and alcoholic liver disease (ALD) progression. A rat ALD model was used to study 5hmC in relationship to hepatocyte apoptosis. Human ALD liver samples were also used to validate these findings. It was found that chronic ethanol feeding significantly reduced 5hmC formation in a rat ALD model. There were no significant changes in TET2 and TET3 between the control- and ethanol-fed animals. In contrast, methylcytosine dioxygenase TET1 (TET1) expression was substantially reduced in the ethanol-fed rats and was accompanied by increased hepatocyte apoptosis. Similarly, knockdown of TET1 in human hepatocyte-like cells also significantly promoted apoptosis. Down-regulation of TET1 resulted in elevated expression of the DNA damage marker, suggesting a role for 5hmc in hepatocyte DNA damage as well. Mechanistic studies revealed that inhibition of TET1 promoted apoptotic gene expression. Similarly, targeting TET1 activity by removing cosubstrate promoted apoptosis and DNA damage. Furthermore, treatment with 5-azacitidine significantly mimics these effects, suggesting that chronic ethanol consumption promotes hepatocyte apoptosis and DNA damage by diminishing TET1-mediated 5hmC formation and DNA methylation. In summary, the current study provides a novel molecular insight that TET1-mediated 5hmC is involved in hepatocyte apoptosis in ALD progression.-Ji, C., Nagaoka, K., Zou, J., Casulli, S., Lu, S., Cao, K. Y., Zhang, H., Iwagami, Y., Carlson, R. I., Brooks, K., Lawrence, J., Mueller, W., Wands, J. R., Huang, C.-K. Chronic ethanol-mediated hepatocyte apoptosis links to decreased TET1 and 5-hydroxymethylcytosine formation.

Cholangiocarcinoma (CCA) is a highly lethal and aggressive disease. Recently, IDH1/2 mutations have been identified in approximately 20% of CCAs which suggests an involvement of 2-oxoglutarate (2-OG) -dependent dioxygenases in oncogenesis. We investigated if the 2-OG dependent dioxygenase, aspartate beta-hydroxylase (ASPH) was important in tumor development and growth. Immunoassays were used to clarify how ASPH modulates CCA progression by promoting phosphorylation of the retinoblastoma protein (RB1). A xenograft model was employed to determine the role of ASPH on CCA growth. Knockdown of ASPH expression inhibited CCA development and growth by reducing RB1 phosphorylation. Expression of ASPH promoted direct protein interaction between RB1, cyclin-dependent kinases, and cyclins. Treatment with 2-OG-dependent dioxygenase and ASPH inhibitors suppressed the interaction between RB1 and CDK4 as well as RB1 phosphorylation. Knockdown of ASPH expression inhibited CCA progression and RB1 phosphorylation in vivo and they were found to be highly expressed in human CCAs. Knockdown of ASPH expression altered CCA development by modulating RB1 phosphorylation, as one of the major factors regulating the growth of these tumors., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The zinc finger E-box-binding homeobox 1 (ZEB1) induced the epithelial-mesenchymal transition (EMT) and altered ZEB1 expression could lead to aggressive and cancer stem cell (CSC) phenotypes in various cancers. Tissue specimens from 96 prostate cancer patients were collected for immunohistochemistry and CD34/periodic acid-Schiff double staining. Prostate cancer cells were subjected to ZEB1 knockdown or overexpression and assessment of the effects on vasculogenic mimicry formation in vitro and in vivo. The underlying molecular events of ZEB1-induced vasculogenic mimicry formation in prostate cancer were then explored. The data showed that the presence of VM and high ZEB1 expression was associated with higher Gleason score, TNM stage, and lymph node and distant metastases as well as with the expression of vimentin and CD133 in prostate cancer tissues. Furthermore, ZEB1 was required for VM formation and altered expression of EMT-related and CSC-associated proteins in prostate cancer cells in vitro and in vivo. ZEB1 also facilitated tumour cell migration, invasion and clonogenicity. In addition, the effects of ZEB1 in prostate cancer cells were mediated by Src signalling; that is PP2, a specific inhibitor of the Src signalling, dose dependently reduced the p-Src 527 level but not p-Src 416 level, while ZEB1 knockdown also down-regulated the level of p-Src 527 in PC3 and DU-145 cells. PP2 treatment also significantly reduced the expression of VE-cadherin, vimentin and CD133 in these prostate cancer cells. Src signalling mediated the effects of ZEB1 on VM formation and gene expression., (© 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

Human coronavirus (HCoV) is one of the most common causes of respiratory tract infection throughout the world. To investigate the epidemiological and genetic variation of HCoV in Guangzhou, south China, we collected totally 13048 throat and nasal swab specimens from adults and children with fever and acute upper respiratory infection symptoms in Gunazhou, south China between July 2010 and June 2015, and the epidemiological features of HCoV and its species were studied. Specimens were screened for HCoV by real-time RT-PCR, and 7 other common respiratory viruses were tested simultaneously by PCR or real-time PCR. HCoV was detected in 294 cases (2.25%) of the 13048 samples, with most of them inpatients (251 cases, 85.4% of HCoV positive cases) and young children not in nursery (53.06%, 156 out of 294 HCoV positive cases). Four HCoVs, as OC43, 229E, NL63 and HKU1 were detected prevalent during 2010-2015 in Guangzhou, and among the HCoV positive cases, 60.20% were OC43, 16.67% were 229E, 14.97% were NL63 and 7.82% were HKU1. The month distribution showed that totally HCoV was prevalent in winter, but differences existed in different species. The 5 year distribution of HCoV showed a peak-valley distribution trend, with the detection rate higher in 2011 and 2013 whereas lower in 2010, 2012 and 2014. The age distribution revealed that children (especially those <3 years old) and old people (>50 years) were both high risk groups to be infected by HCoV. Of the 294 HCoV positive patients, 34.69% (101 cases) were co-infected by other common respiratory viruses, and influenza virus was the most common co-infecting virus (30/101, 29.70%). Fifteen HCoV-OC43 positive samples of 2013-2014 were selected for S gene sequencing and phylogenetic analysis, and the results showed that the 15 strains could be divided into 2 clusters in the phylogenetic tree, 12 strains of which formed a separate cluster that was closer to genotype G found in Malaysia. It was revealed for the first time that genotype B and genotype G of HCoV-OC43 co-circulated and the newly defined genotype G was epidemic as a dominant genotype during 2013-2014 in Guanzhou, south China.

Prostate cancer (PCa) is one of the most common malignant tumors and the second leading cause of cancer-related death among males. Bax-interacting factor-1 (Bif-1) is a member of Endophilin family, which binds to and activates the BAX protein in response to the apoptosis signaling pathway. Loss of Bif-1 may suppress the intrinsic pathway of apoptosis and promote tumorigenesis, but there is also converse evidence that Bif-1 could in part be responsible for the tumorigenesis and the role of Bif-1 in PCa development is not clear. In the present study, we aimed to understand the relationships between Bif-1 expression and PCa development. The mRNA and protein expression levels of Bif-1 in PCa cell lines, benign prostatic hyperplasia (BPH) (n=100) and PCa tissues (n=100, including low Gleason-scored PCa n=43 and high Gleason-scored PCa n=57) were detected and the effects of Bif-1 overexpression on the apoptosis, proliferation and migration in LNCaP cells were explored. Bif-1 mRNA levels of PCa cell lines were analyzed by real-time PCR and the protein levels were detected by western blotting. Bif-1 expression in BPH and PCa samples was detected by immunohistochemistry. To build Bif-1 overexpression PCa cells, Bif-1 gene was transfected into LNCaP cells by pcDNA3.1(+)‑Bif-1 vector. Cell apoptosis was detected by flow cytometric analysis, cell proliferation measured by 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide (MTT) assay and cell migration was analyzed by wound‑healing assay. The results proved that Bif-1 is downregulated in both PCa cell lines (P<0.01) and clinical samples (P<0.05), and Bif-1 expression is suppressed with the cancer progression (BPH vs. PCa P<0.01, and low Gleason-scored PCa vs. high Gleason-scored PCa P<0.05). Overexpression of Bif-1 could significantly inhibit cell proliferation (P<0.05) and enhancing PCa cell apoptosis (P<0.05), but it did not affect the migration ability (P>0.05). Our findings give strong evidence that Bif-1 is involved in PCa tumorigenesis and acts as a suppressor in PCa progression, and may have significance in understanding the process of PCa development.

To understand the clinical epidemiology and molecular characteristics of human bocavirus (HBoV) infection in children with diarrhoea in Guangzhou, South China, we collected 1128 faecal specimens from children with diarrhoea from July 2010 to December 2012. HBoV and five other major enteric viruses were examined using real-time polymerase chain reaction. Human rotavirus (HRV) was the most prevalent pathogen, detected in 250 (22·2%) cases, followed by enteric adenovirus (EADV) in 76 (6·7%) cases, human astrovirus (HAstV) in 38 (3·4%) cases, HBoV in 17 (1·5%) cases, sapovirus (SaV) in 14 (1·2%) cases, and norovirus (NoV) in 9 (0·8%) cases. Co-infections were identified in 3·7% of the study population and 23·5% of HBoV-positive specimens. Phylogenetic analysis revealed 14 HBoV strains to be clustered into species HBoV1 with only minor variations among them. Overall, the detection of HBoV appears to partially contribute to the overall detection gap for enteric infections, single HBoV infection rarely results in severe clinical outcomes, and HBoV sequencing data appears to support conserved genomes across strains identified in this study.

A rapid method based on pressurized liquid extraction followed by high-performance liquid chromatography coupled with evaporative light scattering detection was firstly developed for the quantitative analysis of two bioactive triterpenoids (acankoreoside A and acankoreagenin) in the leaves of Schefflera octophylla and Schefflera actinophylla. The analysis was performed on an Agilent Zorbax SB-Aq column (4.6 × 50 mm, 3.5 μm) with gradient elution of 0.1% formic acid and acetonitrile. Calibration curves of two analytes showed good linearity (R(2) > 0.9990) within the tested ranges. This novel method is simple, rapid and accurate, and the results of quantification showed that contents of each investigated compound is significant high in natural S. octophylla (6.36-14.83%), which indicated that natural S. octophylla as potential medicinal resource. Furthermore, hierarchical clustering analysis based on the typical peaks of acankoreoside A and acankoreagenin from the 17 tested samples showed that natural and cultured Schefflera species were in different clusters, which could provide a means of discriminating between Schefflera species from different origins. Thus, acankoreoside A and acankoreagnin could be selected markers for quality control of S. octophylla and S. actinophylla., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)