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1.
Artif Intell Med ; 151: 102846, 2024 May.
Article in English | MEDLINE | ID: mdl-38547777

ABSTRACT

BACKGROUND AND OBJECTIVES: Generating coherent reports from medical images is an important task for reducing doctors' workload. Unlike traditional image captioning tasks, the task of medical image report generation faces more challenges. Current models for generating reports from medical images often fail to characterize some abnormal findings, and some models generate reports with low quality. In this study, we propose a model to generate high-quality reports from medical images. METHODS: In this paper, we propose a model called Hybrid Discriminator Generative Adversarial Network (HDGAN), which combines Generative Adversarial Network (GAN) with Reinforcement Learning (RL). The HDGAN model consists of a generator, a one-sentence discriminator, and a one-word discriminator. Specifically, the RL reward signals are judged on the one-sentence discriminator and one-word discriminator separately. The one-sentence discriminator can better learn sentence-level structural information, while the one-word discriminator can learn word diversity information effectively. RESULTS: Our approach performs better on the IU-X-ray and COV-CTR datasets than the baseline models. For the ROUGE metric, our method outperforms the state-of-the-art model by 0.36 on the IU-X-ray, 0.06 on the MIMIC-CXR and 0.156 on the COV-CTR. CONCLUSIONS: The compositional framework we proposed can generate more accurate medical image reports at different levels.


Subject(s)
Deep Learning , Diagnostic Imaging , Image Processing, Computer-Assisted , Neural Networks, Computer , Datasets as Topic , Diagnostic Imaging/methods , Image Processing, Computer-Assisted/methods , Radiography, Thoracic , Thorax/diagnostic imaging , Humans
2.
Exp Mol Pathol ; 136: 104889, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38316203

ABSTRACT

Pruritus, also known as itching, is a complex sensation that involves the activation of specific physiological and cellular receptors. The skin is innervated with sensory nerves as well as some receptors for various sensations, and its immune system has prominent neurological connections. Sensory neurons have a considerable impact on the sensation of itching. However, immune cells also play a role in this process, as they release pruritogens. Disruption of the dermal barrier activates an immune response, initiating a series of chemical, physical, and cellular reactions. These reactions involve various cell types, including keratinocytes, as well as immune cells involved in innate and adaptive immunity. Collective activation of these immune responses confers protection against potential pathogens. Thus, understanding the molecular and cellular mechanisms that contribute to pruritus in host skin is crucial for the advancement of effective treatment approaches. This review provides a comprehensive analysis of the present knowledge concerning the molecular and cellular mechanisms underlying itching signaling in the skin. Additionally, this review explored the integration of these mechanisms with the broader context of itch mediators and the expression of their receptors in the skin.


Subject(s)
Pruritus , Skin , Humans , Pruritus/genetics , Pruritus/metabolism , Keratinocytes , Sensory Receptor Cells/metabolism , Signal Transduction
3.
ACS Synth Biol ; 12(12): 3506-3513, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37948662

ABSTRACT

There is a growing need for applications capable of handling large synthesis biology experiments. At the core of synthetic biology is the process of cloning and manipulating DNA as plasmids. Here, we report the development of an application named DNAda capable of writing automation instructions for any given DNA construct design generated by the J5 DNA assembly program. We also describe the automation pipeline and several useful features. The pipeline is particularly useful for the construction of combinatorial DNA assemblies. Furthermore, we demonstrate the platform by constructing a library of polyketide synthase parts, which includes 120 plasmids ranging in size from 7 to 14 kb from 4 to 7 DNA fragments.


Subject(s)
DNA , Synthetic Biology , Plasmids/genetics , DNA/genetics , Gene Library , Automation , Cloning, Molecular
4.
Molecules ; 27(7)2022 Mar 30.
Article in English | MEDLINE | ID: mdl-35408641

ABSTRACT

To develop an appropriate sampling strategy to assess the intrauterine exposure to dechlorane plus (DP), we investigated DP levels in sequential maternal blood samples collected in three trimesters of pregnancy, respectively, from women living in Taizhou. The median concentration of DPs (sum of syn-DP and anti-DP) in all samples was 30.5 pg g−1 wet-weight and 5.01 ng g−1 lipid-adjusted weight, respectively. The trimester-related DP concentrations were consistently strongly correlated (p < 0.01), indicating that a single measurement of DP levels could represent intrauterine exposure without sampling from the same female repeatedly; however, the wet-weight levels significantly increased across trimesters (p < 0.05), while the lipid-adjusted levels did not significantly vary. Notably, whether lipid-adjusted weight or wet-weight levels, the variation extent of DP across trimesters was found to be less than 41%, and those for other persistent organic pollutants (POPs) reported in the literature were also limited to 100%. The limitation in variation extents indicated that, regardless of the time of blood collection during pregnancy and how the levels were expressed, a single measurement could be extended to screen for exposure risk if necessary. Our study provides different strategies for sampling the maternal blood to serve the requirement for assessment of in utero exposure to DP.


Subject(s)
Flame Retardants , Hydrocarbons, Chlorinated , Polycyclic Compounds , China , Environmental Monitoring , Female , Flame Retardants/analysis , Humans , Hydrocarbons, Chlorinated/analysis , Lipids , Pregnancy , Pregnant Women
5.
Anal Biochem ; 643: 114544, 2022 04 15.
Article in English | MEDLINE | ID: mdl-34973938

ABSTRACT

This work developed an electrochemical impedance spectroscopy (EIS) sensor for detection of EGFR (epidermal growth factor receptor)-overexpressing tumor cell and preliminary estimation of EGFR expression. Here, EGFR antibodies as the specific antibodies for cancer cells were conjugated on magnetic gold-decorated graphene oxide nanocomposites, which were used to capture the EGFR-overexpressing tumor cells. The magnetically responsive tumor cells were enriched and immobilized on a magnetic glassy carbon electrode (mGCE) surface, leading to increased electron-transfer resistance (Ret) utilized for determination of cells and preliminary evaluation of EGFR expression level. This strategy enables the enrichment, fixation and detection of tumor cells to be accomplished in a facile way. An excellent linearity in the range of 2.0 × 102 - 3.0 × 105 cell mL-1 with the detection limit of 152 cell mL-1 for MDA-MB-231 cells was obtained. Investigation on the expression levels of EGFR on various types of cells was conducted. MDA-MB-231 cells showed a distinctly higher EGFR expression, compared with MHCC97-L and L02 cells, providing the possibility for the EGFR-targeted therapy of the tumors. It is expected that the proposed sensor has the potential to be applied for cancer monitoring.


Subject(s)
Biosensing Techniques , Electrochemical Techniques , Nanocomposites/chemistry , Carbon/chemistry , Electrodes , ErbB Receptors/biosynthesis , ErbB Receptors/metabolism , Gold/chemistry , Graphite/chemistry , Humans , Magnetic Phenomena , Tumor Cells, Cultured
6.
J Clin Med ; 12(1)2022 Dec 30.
Article in English | MEDLINE | ID: mdl-36615092

ABSTRACT

Whether joint replacement surgery can be performed safely on HIV patients is still a matter of debate. This study aimed to report the surgical efficacy and complications of joint replacement surgery in HIV patients. A total of 21 HIV patients and 27 non-HIV patients who underwent arthroplasties in our hospital were retrospectively reviewed. The 21 HIV patients received 29 joint replacement surgeries including 27 cases of total hip arthroplasty (THA) and 2 cases of total knee arthroplasty (TKA). The non-HIV patients received 16 THA, 10 TKA, and 3 unicompartmental arthroplasty (UKA). The length of hospital stay of HIV patients was significantly lower than that of non-HIV patients. At the last follow-up, there were no significant complications both in the HIV group and the non-HIV groups. No medical staff had any occupational exposure. We concluded that joint replacement surgery in HIV patients is safe and effective. Optimization of patients is key to treatment success. Strictly following the standardized protection protocol can prevent the risk of occupational exposure.

7.
Int J Mol Sci ; 24(1)2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36613454

ABSTRACT

Bacterial leaf streak (BLS) caused by Xanthomonas oryzae pv. oryzicola (Xoc) is one of the most important quarantine diseases in the world. Breeding disease-resistant varieties can solve the problem of prevention and treatment of BLS from the source. The discovery of the molecular mechanism of resistance is an important driving force for breeding resistant varieties. In this study, a BLS-resistant near isogenic line NIL-bls2 was used as the material. Guangxi Xoc strain gx01 (abbreviated as WT) and its mutant strain (abbreviated as MT) with a knockout type III effectors (T3Es) gene were used to infect rice material NIL-bls2. The molecular interaction mechanism of rice resist near isogenic lines in response to infection by different pathogenic strains was analyzed by transcriptome sequencing. The results showed that there were 415, 134 and 150 differentially expressed genes (DEGs) between the WT group and the MT group at 12, 24 and 48 h of post inoculation (hpi). Through GO and KEGG enrichment analysis, it was found that, compared with non-pathogenic strains, the T3Es secreted by pathogenic strains inhibited the signal transduction pathway mediated by ethylene (ET), jasmonic acid (JA) and salicylic acid (SA), and the MAPKK (MAPK kinase) and MAPKKK (MAPK kinase kinase) in the MAPK (mitogen-activated protein kinase) cascade reaction, which prevented plants from sensing extracellular stimuli in time and starting the intracellular immune defense mechanism; and inhibited the synthesis of lignin and diterpenoid phytochemicals to prevent plants from establishing their own physical barriers to resist the invasion of pathogenic bacteria. The inhibitory effect was the strongest at 12 h, and gradually weakened at 24 h and 48 h. To cope with the invasion of pathogenic bacteria, rice NIL-bls2 material can promote wound healing by promoting the synthesis of traumatic acid at 12 h; at 24 h, hydrogen peroxide was degraded by dioxygenase, which reduced and eliminated the attack of reactive oxygen species on plant membrane lipids; and at 48 h, rice NIL-bls2 material can resist the invasion of pathogenic bacteria by promoting the synthesis of lignin, disease-resistant proteins, monoterpene antibacterial substances, indole alkaloids and other substances. Through transcriptome sequencing analysis, the molecular interaction mechanism of rice resistance near isogenic lines in response to infection by different pathogenic strains was expounded, and 5 genes, Os01g0719300, Os02g0513100, Os03g0122300, Os04g0301500, and Os10g0575100 closely related to BLS, were screened. Our work provides new data resources and a theoretical basis for exploring the infection mechanism of Xoc strain gx01 and the resistance mechanism of resistance gene bls2.


Subject(s)
Oryza , Xanthomonas , Virulence/genetics , Lignin/metabolism , China , Plant Breeding , Gene Expression Profiling , Oryza/microbiology , Plant Diseases/microbiology
8.
Adv Healthc Mater ; 10(22): e2101515, 2021 11.
Article in English | MEDLINE | ID: mdl-34558227

ABSTRACT

Numerous nanomedicines currently emerge to reduce the dramatic threat in antibiotics resistance for antibacterial application against severe bacterial infections, while it is restricted by over-reacted immune response to pathogenic bacteria. Herein, enzymatic activity is introduced into the zeolitic imidazolate framework-8 (ZIF-8) to achieve sterilization by releasing Zn ions, as well as inflammation regulation through the variable valence of Mn ions that are uniformly doped into its framework. Within this simple metal organic framework (MOF) structure design, Mn-ZIF-8 possesses the co-existence of Mn2+ /Mn4+ to endow the nanocomposite with the anti-inflammatory capabilities, which can be adjusted through the redox environment. The enzymatic activity of Mn ions and superiority of pore structure of ZIF-8 are effectively combined to realize the substrate selection via reactant molecular size and high-efficiency internal catalytic performance. By such design, this nanocomposite would not only exhibit an excellent antibacterial performance against pathogenic bacteria, but also reshape the inflammatory immunity by regulating macrophage polarization to suppress over-reacted inflammation, leading to a favorably therapeutic efficiency on bacteria-infected wound healing in animal models. Taken together, this nanoplatform provides effective approach for accelerating infected wound healing via bacteria killing and inflammation modulation, and may be extended for the therapy of other severe bacteria-induced infections.


Subject(s)
Zeolites , Animals , Anti-Bacterial Agents/pharmacology , Imidazoles , Immunity , Immunomodulation , Ions , Manganese , Wound Healing
9.
Small ; 17(41): e2101505, 2021 10.
Article in English | MEDLINE | ID: mdl-34499411

ABSTRACT

Macrophage polarization toward M1 phenotype (pro-inflammation) is closely associated with the destructive phase of periodontal inflammation. Nanoceria is verified to inhibit M1 polarization of macrophages by the favorable ability of reactive oxygen species (ROS) scavenging. However, the function of nanoceria on macrophage polarization toward M2 phenotype (anti-inflammation) in reparative phase of periodontal inflammation is quite limited. In this work, by introducing an antioxidant drug quercetin onto nano-octahedral ceria, synergistic and intense regulation of host immunity against periodontal disease is realized. Such nanocomposite can control the phenotypic switch of macrophages by not only inhibition of M1 polarization for suppressing the damage in the destructive phase but also promotion of M2 polarization for regenerating the surrounding tissues in reparative phase of periodontal disease. As-prepared nanocomposite can effectively increase the M2/M1 ratio of macrophage polarization in inflammatory cellular models by lipopolysaccharide stimulation. More importantly, the nanocomposite also exerts an improved therapeutic potential against local inflammation by significant downregulation of pro-inflammatory cytokines and upregulation of anti-inflammatory cytokines in an animal model with periodontal inflammation. Therefore, this newly developed nanomedicine is efficient in ROS scavenging and driving pro-inflammatory macrophages to the anti-inflammatory phenotype to eliminate inflammation, thereby providing a promising candidate for treating periodontal inflammation.


Subject(s)
Nanocomposites , Quercetin , Animals , Inflammation/drug therapy , Macrophage Activation , Macrophages
10.
Biomed Pharmacother ; 128: 110372, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32521458

ABSTRACT

The heavy burden of oral diseases such as oral cancers, dental caries, periodontitis, etc. and their consequence on the patient's quality of life demonstrated an urgent demand for developing effective therapeutics. Quercetin as a natural derived flavonoid, could be utilized in the therapeutic formulation of various diseases such as diabetes, breast cancer and asthma, owing to its prominent pharmacological values. In the last decade, the applications of quercetin as a natural compound in oral treatment have attracted increasing interest due to its multifunction including antioxidant, antibacterial, anti-inflammatory and antineoplastic activities. Besides, considering the low bioavailability of quercetin, great efforts have been made in its drug delivery systems to address the problem of limited application. Therefore, this review summarized the cutting-edge researches on versatile effects and enhanced bioavailability of quercetin resulting from innovative drug delivery systems, particularly focused on its potential against oral diseases. The application of quercetin would provide novel and promising therapeutic approach for clinical treatment, promoting the development of global dental public health.


Subject(s)
Drug Carriers , Mouth Diseases/drug therapy , Quercetin/administration & dosage , Administration, Oral , Animals , Biological Availability , Drug Compounding , Humans , Quercetin/chemistry , Quercetin/pharmacokinetics
11.
Article in English | MEDLINE | ID: mdl-32596233

ABSTRACT

Nowadays, the heavy burden of oral diseases such as dental caries, periodontitis, endodontic infections, etc., and their consequences on the patients' quality of life indicate a strong need for developing effective therapies. Bacterial infections played an important role in the field of oral diseases, in-depth insight of such oral diseases have given rise to the demand for antibacterial therapeutic strategies. Recently, microporous frameworks have attracted tremendous interest in antibacterial application due to their well-defined porous structures for drug delivery. In addition, intensive efforts have been made to enhance the antibacterial performance of microporous frameworks, such as ion doping, photosensitizer incorporation as building blocks, and surface modifications. This review article aims on the major recent developments of microporous frameworks for antibacterial applications against oral diseases. The first part of this paper puts concentration on the cutting-edge researches on the versatile antibacterial strategies of microporous materials via drug delivery, inherent activity, and structural modification. The second part discusses the antibacterial applications of microporous frameworks against oral diseases. The applications of microporous frameworks not only have promising therapeutic potential to inhibit bacterial plaque-initiated oral infectious diseases, but also have a wide applicability to other biomedical applications.

12.
Mitochondrial DNA B Resour ; 5(3): 2469-2470, 2020 Jun 16.
Article in English | MEDLINE | ID: mdl-33457830

ABSTRACT

In this study, the complete chloroplast genome of Pholidota yunnanensis is presented, which represents first complete plastid genome of the genus Pholidota in the subtribe Coelogyninae. The chloroplast genome size is 159,729 bp, including a GC content of 37.3% and 135 genes (89 protein-coding genes, 38 tRNA genes, 8 rRNA genes). The genome structure is typical quadripartite, consisting of a pair of inverted repeat regions (26,638 bp) separated by a large single-copy region (LSC, 87,610 bp) and a small single-copy region (SSC, 18,843 bp). Phylogenetic analysis among 15 species based on cp genomes recovered a well-supported phylogenetic tree and indicated a close relationship between Pholidota yunnanensis and Pleione bulbocodioides.

13.
J Diabetes Res ; 2019: 6757428, 2019.
Article in English | MEDLINE | ID: mdl-31886284

ABSTRACT

Osteocyte plays an essential role in bone metabolism by regulating osteoblast and osteoclast activities. Dysfunction or apoptosis of osteocyte will severely endanger the bone homeostasis and result in bone diseases such as osteoporosis. Osteoporosis has been considered as one of the diabetes complications; however, the mechanism is still to be discovered. Advanced glycation end products (AGEs), as the main pathogenic factor of diabetes mellitus, have the capacity to induce osteocyte apoptosis thus sabotaging bone homeostasis. Here, we examined the role of AGE during osteocyte apoptosis and how this effect would affect osteocyte's regulation of osteoblast and osteoclast. Mouse osteocyte-like MLO-Y4 cells were used to study the properties of osteocyte and to examine its biological and pathological function. MTT assay and Annexin V assay showed that AGE significantly induce MLO-Y4 cell apoptosis. qPCR and Western blot results have shown that AGE upregulates proapoptotic gene p53 and its downstream target gene Bax, which leads to enhanced activation of caspase-3, thus inducing apoptosis in MLO-Y4 cells. Increased expression of sclerostin and RANKL in osteocytes has shown that AGE induces osteocyte dysfunction thus severely damaging the bone homeostasis by decreasing osteoblast and increasing osteoclast activities. Furthermore, the role of the transcription factor FOXO1, which is intensely associated with apoptosis, has been determined. Western blot has shown that AGE significantly decreases Akt activities. Immunofluorescence has shown that AGE promotes FOXO1 nuclei localization and enhances FOXO1 expression. Silencing of FOXO1 suppressed AGE-enhanced apoptosis; mRNA and protein expressions of cleaved caspase-3, sclerostin, and RANKL were downregulated as well. Moreover, exogenous FOXO1 increased caspase-3 mRNA levels and caspase-3 transcriptional activity. Lastly, ChIP assay has established the capacity of FOXO1 binding directly on the caspase-3, sclerostin, and RANKL promoter region in AGE environment, providing the mechanism of the AGE-induced osteocyte apoptosis and dysfunction. Our results have shown that FOXO1 plays a crucial role in AGE-induced osteocyte dysfunction and apoptosis through its regulation of caspase-3, sclerostin, and RANKL. This study provides new insight into diabetes-enhanced risk of osteoporosis given the critical role of AGE in the pathogenesis of diabetes and the essential part of osteocyte in bone metabolism.


Subject(s)
Apoptosis/drug effects , Forkhead Box Protein O1/metabolism , Glycation End Products, Advanced/toxicity , Osteocytes/drug effects , Serum Albumin, Bovine/toxicity , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Animals , Binding Sites , Caspase 3/genetics , Caspase 3/metabolism , Cell Line , Forkhead Box Protein O1/genetics , Gene Expression Regulation , Mice , Osteocytes/metabolism , Osteocytes/pathology , Promoter Regions, Genetic , RANK Ligand/genetics , RANK Ligand/metabolism , Signal Transduction , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
14.
Int J Mol Sci ; 20(24)2019 Dec 06.
Article in English | MEDLINE | ID: mdl-31817689

ABSTRACT

Chirality is an important property of molecules. The study of biological activity and toxicity of chiral molecules has important theoretical and practical significance for toxicology, pharmacology, and environmental science. The toxicological significance of chiral ionic liquids (ILs) has not been well revealed. In the present study, the enantiomeric joint toxicities of four pairs of chiral ILs 1-alkyl-3-methylimidazolium lactate to Allivibrio fischeri were systematically investigated by using a comprehensive approach including the co-toxicity coefficient (CTC) integrated with confidence interval (CI) method (CTCICI), concentration-response curve (CRC), and isobole analysis. The direct equipartition ray (EquRay) design was used to design five binary mixtures of enantiomers according to molar ratios of 1:5, 2:4, 3:3, 4:2, and 5:1. The toxicities of chiral ILs and their mixtures were determined using the microplate toxicity analysis (MTA) method. Concentration addition (CA) and independent action (IA) were used as the additive reference models to construct the predicted CRC and isobole of mixtures. On the whole, there was an enantioselective toxicity difference between [BMIM]D-Lac and [BMIM]L-Lac, and [HMIM]D-Lac and [HMIM]L-Lac, while no enantioselective toxicity difference was observed for [EMIM]D-Lac and [EMIM]L-Lac, and [OMIM]D-Lac and [OMIM]L-Lac. Thereinto, the enantiomer mixtures of [BMIM]D-Lac and [BMIM]L-Lac, and [HMIM]D-Lac and [HMIM]L-Lac presented antagonistic action, and the enantiomer mixtures of [EMIM]D-Lac and [EMIM]L-Lac, and [OMIM]D-Lac and [OMIM]L-Lac overall presented additive action. Moreover, the greatest antagonistic toxicity interaction occurred at the equimolar ratio of enantiomers. Based on these results, we proposed two hypotheses, (1) chiral molecules with enantioselective toxicity difference tended to produce toxicity interactions, (2) the highest or lowest toxicity was usually at the equimolar ratio and its adjacent ratio for the enantiomer mixture. These hypotheses will need to be further validated by other enantiomer mixtures.


Subject(s)
Aliivibrio fischeri/drug effects , Ionic Liquids/chemistry , Ionic Liquids/pharmacology , Stereoisomerism
15.
PhytoKeys ; 136: 97-106, 2019.
Article in English | MEDLINE | ID: mdl-31892815

ABSTRACT

P. wenshanica S.C.Chen & Z.H.Tsi and P. subcalceata Gagnep. have long been recognized as synonyms of P. leveilleana Schltr. In the present study, detailed morphological comparisons suggest that specimens referred to as P. wenshanica and P. subcalceata differ significantly in both vegetative and floral characters from those of P. leveilleana. Here we resurrect P. wenshanica and P. subcalceata as independent species. Key diagnostic characters essential for delineating identities of these species are presented.

16.
Genes Dev ; 32(19-20): 1309-1314, 2018 10 01.
Article in English | MEDLINE | ID: mdl-30228203

ABSTRACT

The mitochondrial cytoplasmic surface serves as a processing site for numerous RNAs from budding yeast to metazoans. We report that budding yeast mitochondrial outer membrane (MOM) proteins that are subunits of the translocase of the outer mitochondrial membrane (Tom70 and Tom 22) and sorting and assembly machinery (Sam37) are required for efficient pretransfer RNA (pre-tRNA) splicing. Defective pre-tRNA splicing in MOM mutants is due not to loss of respiratory metabolism but instead inefficient targeting/tethering of tRNA splicing endonuclease (SEN) subunits to mitochondria. Schizosaccharomyces pombe SEN subunits also localize to mitochondria, and Tom70 is required for this localization and pre-tRNA splicing. Thus, the role of MOM protein in targeting/tethering SEN subunits to mitochondria has been conserved for >500 million years.


Subject(s)
Endoribonucleases/metabolism , Membrane Proteins/physiology , Mitochondrial Membrane Transport Proteins/physiology , RNA Splicing , RNA, Transfer/metabolism , Saccharomyces cerevisiae Proteins/physiology , Cell Respiration , Membrane Proteins/genetics , Mitochondria/enzymology , Mitochondrial Membrane Transport Proteins/genetics , Mitochondrial Precursor Protein Import Complex Proteins , Mutation , Protein Subunits/metabolism , RNA Transport , Saccharomyces cerevisiae/enzymology , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics , Schizosaccharomyces/enzymology , Schizosaccharomyces/metabolism , Schizosaccharomyces pombe Proteins/metabolism , Schizosaccharomyces pombe Proteins/physiology
17.
Genes Dev ; 32(9-10): 600-601, 2018 05 01.
Article in English | MEDLINE | ID: mdl-29802122

ABSTRACT

Circular RNAs (circRNAs) comprise a recently appreciated category of RNAs that are in high abundance and serve important biological functions. Although several discoveries have been made regarding the biogenesis and functions of circRNAs, their subcellular trafficking has remained largely unknown. In this issue of Genes & Development, Huang and colleagues (pp. 639-644) reported the first study of the nuclear export of circRNAs. Drosophila Hel25E and its human homologs, UAP56 and URH49, are required for nuclear export of circRNAs. Nuclear export of circRNAs is surprisingly length-dependent, and the length measurement mechanism was shown to be controlled by motifs in Hel25E and its homologs consisting of four amino acids.


Subject(s)
DEAD-box RNA Helicases , RNA , Active Transport, Cell Nucleus , Amino Acids , Humans , Protein Transport
18.
Biochim Biophys Acta Gene Regul Mech ; 1861(4): 373-386, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29191733

ABSTRACT

Although tRNAs participate in the essential function of protein translation in the cytoplasm, tRNA transcription and numerous processing steps occur in the nucleus. This subcellular separation between tRNA biogenesis and function requires that tRNAs be efficiently delivered to the cytoplasm in a step termed "primary tRNA nuclear export". Surprisingly, tRNA nuclear-cytoplasmic traffic is not unidirectional, but, rather, movement is bidirectional. Cytoplasmic tRNAs are imported back to the nucleus by the "tRNA retrograde nuclear import" step which is conserved from budding yeast to vertebrate cells and has been hijacked by viruses, such as HIV, for nuclear import of the viral reverse transcription complex in human cells. Under appropriate environmental conditions cytoplasmic tRNAs that have been imported into the nucleus return to the cytoplasm via the 3rd nuclear-cytoplasmic shuttling step termed "tRNA nuclear re-export", that again is conserved from budding yeast to vertebrate cells. We describe the 3 steps of tRNA nuclear-cytoplasmic movements and their regulation. There are multiple tRNA nuclear export and import pathways. The different tRNA nuclear exporters appear to possess substrate specificity leading to the tantalizing possibility that the cellular proteome may be regulated at the level of tRNA nuclear export. Moreover, in some organisms, such as budding yeast, the pre-tRNA splicing heterotetrameric endonuclease (SEN), which removes introns from pre-tRNAs, resides on the cytoplasmic surface of the mitochondria. Therefore, we also describe the localization of the SEN complex to mitochondria and splicing of pre-tRNA on mitochondria, which occurs prior to the participation of tRNAs in protein translation. This article is part of a Special Issue entitled: SI: Regulation of tRNA synthesis and modification in physiological conditions and disease edited by Dr. Boguta Magdalena.


Subject(s)
Cell Nucleus/metabolism , Cytoplasm/metabolism , Mitochondrial Membranes/metabolism , Nucleocytoplasmic Transport Proteins/metabolism , RNA, Transfer/metabolism , Animals , Biological Transport , Endoribonucleases/metabolism , Evolution, Molecular , Fungal Proteins/metabolism , HSP70 Heat-Shock Proteins/metabolism , Nuclear Pore Complex Proteins/metabolism , Plant Proteins/metabolism , RNA Precursors/metabolism , RNA Processing, Post-Transcriptional , RNA-Binding Proteins/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Transcription, Genetic , Vertebrates/metabolism , Yeasts/metabolism
19.
Acupuncture Research ; (6): 163-168, 2018.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-844481

ABSTRACT

OBJECTIVE: To assess the effect of electroacupuncture (EA) on chronic inflammatory response of Leydig cells in aged rats with low testosterone, so as to investigate its underlying mechanism of anti-male reproductive aging. METHODS: Twenty-four 20 months old SD rats were randomly divided into EA, medication and aged control groups (n= 8 in each), and other 8 young SD rats (2 months of age) were used as the youth control group. EA (2 Hz/100 Hz, 1 mA) was applied to "Guanyuan"(CV 4) and bilate-ral "Shenshu"(BL 23) for 15 min, once daily for 8 weeks except the weekends. The medication group received abdominal subcutaneous injection of testosterone propionate (7 mg• kg-1• 3 d-1) for 8 weeks. The aged control group and the youth control group received subcutaneous injection of 0.9% normal saline, with the same dose and same treatment frequency as those of the medication group. The rats' physical power was assessed according to the exhausted swimming duration, and the levels of serum total testosterone (TT) and free testosterone(FT) were determined by ELISA. The pathological changes of the testis tissue were detected by using H.E.staining, and the immunoactivity of cyclooxygenase-2 (COX-2) in Leydig cells was detected by immunohisto-chemistry. The expression levels of nuclear factor-κB p 65 (NF-κB p 65), COX-2, interleukin-1 β (IL-1 β) and tumor necrosis factor-α (TNF-α) proteins in the testis tissues were determined by Western blot. RESULTS: Before and after treatment, the exhaustive swimming duration and the levels of serum TT and FT in the aged control group were significantly lower than those of the youth control group (P < 0.01). After the treatment, the exhaustive swimming duration and serum TT and FT in the EA and medication groups were notably higher than those in the aged control group (P<0.01). HE staining showed that the incompleteness of basement membrane of spermatogenic tubules, reduction of spermatogenic cells and supporting cells and irregularity of Leydig cells in the testis tissue of the aged rats were relatively milder after EA intervention. Compared with the youth control group, the expression levels of NF-κB p 65 and COX-2, IL-1 β and TNF-α in the testicular tissue were significantly higher in the aged control group (P<0.01),while in compared with the aged control group, the expression levels of NF-κB p 65, COX-2, IL-1 β and TNF-α proteins were significantly down-regulated in the EA group (P<0.01). CONCLUSION: EA intervention can improve the physical power of the aged rats with low testosterone, which may be related to its effects in up-regulating TT and FT levels, and in reducing chronic inflammatory response in the testis tissue.

20.
Genes Dev ; 31(21): 2186-2198, 2017 11 01.
Article in English | MEDLINE | ID: mdl-29212662

ABSTRACT

Eukaryotic transfer RNAs (tRNAs) are exported from the nucleus, their site of synthesis, to the cytoplasm, their site of function for protein synthesis. The evolutionarily conserved ß-importin family member Los1 (Exportin-t) has been the only exporter known to execute nuclear export of newly transcribed intron-containing pre-tRNAs. Interestingly, LOS1 is unessential in all tested organisms. As tRNA nuclear export is essential, we previously interrogated the budding yeast proteome to identify candidates that function in tRNA nuclear export. Here, we provide molecular, genetic, cytological, and biochemical evidence that the Mex67-Mtr2 (TAP-p15) heterodimer, best characterized for its essential role in mRNA nuclear export, cofunctions with Los1 in tRNA nuclear export. Inactivation of Mex67 or Mtr2 leads to rapid accumulation of end-matured unspliced tRNAs in the nucleus. Remarkably, merely fivefold overexpression of Mex67-Mtr2 can substitute for Los1 in los1Δ cells. Moreover, in vivo coimmunoprecipitation assays with tagged Mex67 document that the Mex67 binds tRNAs. Our data also show that tRNA exporters surprisingly exhibit differential tRNA substrate preferences. The existence of multiple tRNA exporters, each with different tRNA preferences, may indicate that the proteome can be regulated by tRNA nuclear export. Thus, our data show that Mex67-Mtr2 functions in primary nuclear export for a subset of yeast tRNAs.


Subject(s)
Active Transport, Cell Nucleus/genetics , Proteome/genetics , RNA, Transfer/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Gene Silencing , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Nuclear Pore Complex Proteins/genetics , Nuclear Pore Complex Proteins/metabolism , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Nucleocytoplasmic Transport Proteins/genetics , Nucleocytoplasmic Transport Proteins/metabolism , Protein Binding , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism
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