28 results on '"Tongyu Li"'
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2. Influence of the 1,3-Bis(trimethylsilyl)cyclopentadienyl Ligand on the Reactivity of the Uranium Phosphinidene [η5-1,3-(Me3Si)2C5H3]2U(═P-2,4,6-iPr3C6H2)(OPPh3)
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Shichun Wang, Guohua Hou, Yi Heng, Tongyu Li, Marc D. Walter, and Guofu Zi
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Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Trimethylsilyl ,Cyclopentadienyl complex ,Phosphinidene ,Ligand ,Organic Chemistry ,chemistry.chemical_element ,Reactivity (chemistry) ,Physical and Theoretical Chemistry ,Uranium ,Medicinal chemistry - Published
- 2021
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3. Synthesis and reactivity of the uranium phosphinidene metallocene [η5-1,3-(Me3Si)2C5H3]2U(P-2,4,6-iPr3C6H2)(OPMe3): influence of the coordinated Lewis base
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Guofu Zi, Yi Heng, Marc D. Walter, Guohua Hou, Tongyu Li, and Shichun Wang
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Inorganic Chemistry ,chemistry.chemical_compound ,Denticity ,chemistry ,Ligand ,Phosphinidene ,Yield (chemistry) ,Molecule ,Reactivity (chemistry) ,Lewis acids and bases ,Medicinal chemistry ,Metallocene - Abstract
This paper describes the synthesis and reactivity of [η5-1,3-(Me3Si)2C5H3]2U(P-2,4,6-iPr3C6H2)(OPMe3) (6) which is accessible from a ligand exchange reaction between [η5-1,3-(Me3Si)2C5H3]2U(P-2,4,6-iPr3C6H2)(OPPh3) (2) and Me3PO at ambient temperature. Phosphinidene 6 exhibits no reactivity towards internal alkynes, but readily reacts with various hetero-unsaturated molecules such as isothiocyanates, aldehydes, nitriles, isonitriles, and organic azides, forming uranium sulfido, oxido, imido, and uranaheterocyclic compounds. Nevertheless, with the bidentate ortho-dicyanobenzene o-C6H4(CN)2 the zwitterionic species [η5-1,3-(Me3Si)2C5H3]2U[NHC(N){C6H4CP(2,4,6-iPr3C6H2)CH2PMe2O}] (13) is isolated in good yield. Moreover, 6 converts with Ph2S2 to the uranium(III) phenylthiolate compound [η5-1,3-(Me3Si)2C5H3]2USPh(OPMe3) (7) in good isolated yield. Furthermore, the influence of the Lewis base on the reactivity of the uranium phosphinidene metallocenes has also been evaluated.
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- 2021
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4. Reactivity studies involving a Lewis base supported terminal uranium phosphinidene metallocene [η5-1,3-(Me3C)2C5H3]2U(P-2,4,6-iPr3C6H2)(OPMe3)
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Gouhua Hou, Tongyu Li, Yi Heng, Shichun Wang, Deqiang Wang, Guofu Zi, and Marc D. Walter
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chemistry.chemical_classification ,Double bond ,010405 organic chemistry ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Phosphinidene ,Salt metathesis reaction ,Molecule ,Reactivity (chemistry) ,Lewis acids and bases ,Metallocene ,Derivative (chemistry) - Abstract
The Lewis base supported terminal uranium phosphinidene metallocene [η5-1,3-(Me3C)2C5H3]2U([double bond, length as m-dash]P-2,4,6-iPr3C6H2)(OPMe3) (2) could be isolated from a salt metathesis reaction in toluene at ambient temperature between [η5-1,3-(Me3C)2C5H3]2U(Cl)Me (1) and 2,4,6-iPr3C6H2PHK in the presence of Me3PO, and its structure and reactivity were probed in detail. No reaction of 2 with internal alkynes was observed, but it reacts in the presence of various heterounsaturated molecules such as CS2, isothiocyanates, aldehydes, imines, diazenes, carbodiimides, nitriles, isonitriles, diazoalkane, and organic azides, forming carbodithioates, sulfidos, oxidos, metallaheterocycles, and imido complexes, in good yields. Moreover, on reaction with the diazoalkane derivative Me3SiCHN2 the pseudophosphinimido uranium(iii) complex [η5-1,3-(Me3C)2C5H3]2U(N[double bond, length as m-dash]P-2,4,6-iPr3C6H2)(OPMe3) (20) can be isolated in good yield.
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- 2021
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5. Rhodium‐Catalyzed C−H Functionalization of N ‐(2‐Pyrimidyl)indole with Internal Alkynes: Formation of Unexpected Products by Regulating the Amount of Silver Acetate
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Tongyu Li, Zhuo Wang, Chen Chen, and Bolin Zhu
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Indole test ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,chemistry.chemical_element ,Surface modification ,Silver acetate ,General Chemistry ,Catalysis ,Rhodium - Published
- 2019
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6. A general prodrug nanohydrogel platform for reduction-triggered drug activation and treatment of taxane-resistant malignancies
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Jie Yao, Xiaowei Shi, Tongyu Li, Yuchen Wang, Hangxiang Wang, and Shijiang Fang
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Drug ,media_common.quotation_subject ,0206 medical engineering ,Biomedical Engineering ,Context (language use) ,Antineoplastic Agents ,02 engineering and technology ,Pharmacology ,Biochemistry ,Biomaterials ,Activation, Metabolic ,Mice ,Therapeutic index ,In vivo ,Neoplasms ,medicine ,Tumor Microenvironment ,Animals ,Humans ,Prodrugs ,Molecular Biology ,media_common ,Taxane ,Chemistry ,General Medicine ,Prodrug ,021001 nanoscience & nanotechnology ,020601 biomedical engineering ,Cabazitaxel ,Taxoids ,0210 nano-technology ,Biotechnology ,Nanogel ,medicine.drug - Abstract
Chemotherapy has been widely used for treating the vast majority of cancer patients. Unfortunately, only a fraction of patients can respond to chemotherapies, but these patients still experience severe side effects. In this context, a wide range of nanotherapeutic platforms have been developed with the aim of improving treatment outcomes while reducing drug toxicities. Nanohydrogels are highly appealing "smart" biocompatible and biodegradable vehicles for either local or systemic delivery of bioactive compounds. Here, we developed prodrug hydrogelators that can undergo one-step distillation-precipitation polymerization to form systemically injectable nanohydrogels. The optimized nanohydrogels were capable of rapidly releasing active agents (e.g., the cytotoxic agent cabazitaxel or the PI3K molecular inhibitor PI103) in response to the reducing tumor microenvironment, while drug release was very slow in the absence of the reductive reagent glutathione. Cabazitaxel-loaded nanogels showed preferential tumor accumulation, and administration of nanogels produced durable tumor regression in a docetaxel-resistant cervical tumor xenograft-bearing mouse model. More significantly, nanogel-based therapy was proven to demonstrate a higher safety profile than solution-based free cabazitaxel. Collectively, this study provides an alternative formulation that meets the essential requirements of high stability in the blood, spontaneous drug release at diseased sites, favorable safety in vivo, and translational capacity for further investigations. STATEMENT OF SIGNIFICANCE: Chemotherapy remains a considerable challenge and only a fraction of patients can respond to chemotherapies. Here we report an intratumoral reducing agent-activatable, tumor-targeting prodrug nanogel platform for therapeutic delivery. To this end, two anticancer agents (e.g., cytotoxic cabazitaxel or PI3K molecular inhibitor PI103) are tested. Prodrug nanogels are stable in the blood but performed reduction-triggered release of chemically unmodified drug molecules in cancerous tissues. Cabazitaxel-loaded nanogels exhibit satisfactory anticancer performance in a preclinical docetaxel-resistant tumor model. This is a practical and expedient approach that combines the prodrug strategy and nanogel scaffold to re-engineer a hydrophobic and toxic anticancer drug. The approach also is broadly applicable for the formulation of other agents to improve the therapeutic index.
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- 2021
7. New Organometallic Ruthenium(II) Compounds Synergistically Show Cytotoxic, Antimetastatic and Antiangiogenic Activities for the Treatment of Metastatic Cancer
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Yuchen Wang, Hangxiang Wang, Chao Chen, Siming Lu, Tongyu Li, Mohamed Kasim Mohamed Subarkhan, Liwei Shu, and Jiahui Jin
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chemistry.chemical_element ,Antineoplastic Agents ,010402 general chemistry ,01 natural sciences ,Catalysis ,Ruthenium ,Bipyridine ,chemistry.chemical_compound ,Mice ,In vivo ,Antimetastatic Agent ,Cell Line, Tumor ,medicine ,Organometallic Compounds ,Animals ,Humans ,Cytotoxicity ,Tube formation ,Cisplatin ,Ovarian Neoplasms ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,General Chemistry ,0104 chemical sciences ,Chorioallantoic membrane ,Cancer research ,Female ,medicine.drug - Abstract
In this study, we newly designed and synthesized a small library of ten structurally related C,N-cyclometalated ruthenium(II) complexes containing various pyridine-functionalized NHC ligand and chelating bipyridyl ligands (e.g., 2,2'-bipyridine, 5,5'-dimethyl-2,2'-bipyridine, and 1,10-phenanthroline (phen)). The complexes were well characterized by NMR, electrospray ionization-mass spectrometry, and single-crystal X-ray structure analyses. Among the new ruthenium(II) derivatives, we identified that the complex Ru8 bearing bulky moieties (i.e., phen and pentamethyl benzene) had the most potent cytotoxicity against all tested cancer cell lines, generating dose- and cell line-dependent IC50 values at the range of 3.3-15.0 μm. More significantly, Ru8 not only efficiently inhibited the metastasis process against invasion and migration of tumor cells but also exhibited potent antivascular effects by suppressing HUVEC cells migration and tube formation in vitro and blocking vessel generation in vivo (chicken chorioallantoic membrane model). In a metastatic A2780 tumor xenograft-bearing mouse model, administration of Ru8 outperformed antimetastatic agent NAMI-A and clinically approved cisplatin in terms of antitumor efficacy and inhibition of metastases to other organs. Overall, these data provided compelling evidence that the new cyclometalated ruthenium complex Ru8 is an attractive agent because of synergistically suppressing bulky tumors and metastasized tumor nudes. Therefore, the complex Ru8 deserves further investigations.
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- 2020
8. Rhodium(<scp>iii</scp>)-catalyzed unreactive C(sp3)–H alkenylation of N-alkyl-1H-pyrazoles with alkynes
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Chang Liu, Tongyu Li, Shaonan Wu, Bolin Zhu, and Chen Chen
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chemistry.chemical_classification ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,chemistry.chemical_element ,Pyrazole ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Medicinal chemistry ,0104 chemical sciences ,Catalysis ,Rhodium ,chemistry.chemical_compound ,Physical and Theoretical Chemistry ,Alkyl - Abstract
The first example of pyrazole-directed rhodium(III)-catalyzed unreactive C(sp3)–H alkenylation with alkynes has been described, which showed a relatively broad substrate scope with good functional group compatibility. Moreover, we demonstrated that the transitive coordinating center pyrazole could be easily removed under mild conditions.
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- 2019
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9. Inhibition of TRPC1 prevents cardiac hypertrophy via NF-κB signaling pathway in human pluripotent stem cell-derived cardiomyocytes
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Jiaxi Shen, Tongyu Li, Tingyu Gong, Xiaochen Wang, Ling Tang, Bing Dai, Jue Wang, Li Wang, Danni Zhou, Fengfeng Guo, Jun Su, Ping Liang, Hao Wang, Fang Yao, Hongkun Wang, and Haodi Wu
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Pluripotent Stem Cells ,0301 basic medicine ,Cardiomegaly ,030204 cardiovascular system & hematology ,Muscle hypertrophy ,TRPC1 ,03 medical and health sciences ,chemistry.chemical_compound ,Transient receptor potential channel ,0302 clinical medicine ,medicine ,Humans ,Myocytes, Cardiac ,Induced pluripotent stem cell ,Molecular Biology ,TRPC Cation Channels ,Base Sequence ,business.industry ,NF-kappa B ,Hypertrophic cardiomyopathy ,NF-κB ,medicine.disease ,Cell biology ,030104 developmental biology ,chemistry ,Heart failure ,Phorbol ,Cardiology and Cardiovascular Medicine ,business ,Signal Transduction - Abstract
Cardiac hypertrophy is an adaptive response against increased workload featuring by an increase in left ventricular mass and a thickening left ventricle wall. Here, we showed the expression of transient receptor potential canonical 1 (TRPC1) is higher in hearts of patients with hypertrophic cardiomyopathy (HCM) or heart failure (HF) than that of normal hearts. To better understand the mechanisms of TRPC1 in regulating cellular hypertrophy of human-based cardiomyocytes, we generated human pluripotent stem cell lines of TRPC1 knockout by CRISPR/Cas9. We demonstrated that knockout of TRPC1 significantly attenuated cardiomyocyte hypertrophy phenotype induced by phorbol 12-myristate 13-acetate, which was associated with abnormal activation of NF-κB. In contrast, overexpression of TRPC1 induced cardiomyocyte hypertrophy, which can be reversed by inhibition of NF-κB. Taken together, we established a stable human-based cardiomyocyte hypertrophy model and highlighted molecular mechanisms underlying TRPC1-mediated hypertrophy, aiding the development of therapeutic drugs for HCM and HF by targeting TRPC1.
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- 2019
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10. CHAF1A interacts with TCF4 to promote gastric carcinogenesis via upregulation of c-MYC and CCND1 expression
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Xiuming Liang, Wenjing Shang, Lixin Zheng, Lin Ma, Shuyan Li, Pengpeng Sun, Chunyan Chen, Wei Shao, Tongyu Li, Xiaxia Jia, and Jihui Jia
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0301 basic medicine ,Research paper ,CHAF1A ,Carcinogenesis ,Cell ,medicine.disease_cause ,General Biochemistry, Genetics and Molecular Biology ,Helicobacter Infections ,03 medical and health sciences ,Downregulation and upregulation ,Stomach Neoplasms ,medicine ,Histone chaperone ,Humans ,Gene knockdown ,Helicobacter pylori ,biology ,Oncogene ,Chemistry ,Wnt signaling pathway ,Oncogenes ,General Medicine ,Chromatin Assembly Factor-1 ,030104 developmental biology ,Histone ,medicine.anatomical_structure ,Cancer cell ,biology.protein ,Cancer research ,Gastric cancer - Abstract
Background Histones chaperones have been found to play critical roles in tumor development and progression. However, the role of histone chaperone CHAF1A in gastric carcinogenesis and its underlying mechanisms remain elusive. Methods CHAF1A expression in gastric cancer (GC) was analyzed in GEO datasets and clinical specimens. CHAF1A knockdown and overexpression were used to explore its functions in gastric cancer cells. The regulation and potential molecular mechanism of CHAF1A expression in gastric cancer cells were studied by using cell and molecular biological methods. Findings CHAF1A was upregulated in GC tissues and its high expression predicted poor prognosis in GC patients. Overexpression of CHAF1A promoted gastric cancer cell proliferation both in vitro and in vivo, whereas CHAF1A suppression exhibited the opposite effects. Mechanistically, CHAF1A acted as a co-activator in the Wnt pathway. CHAF1A directly interacted with TCF4 to enhance the expression of c-MYC and CCND1 through binding to their promoter regions. In addition, the overexpression of CHAF1A was modulated by specificity protein 1 (Sp1) in GC. Sp1 transcriptionally enhanced the expression of CHAF1A in GC. Furthermore, CHAF1A expression induced by Helicobacter pylori was Sp1 dependent. Interpretation CHAF1A is a potential oncogene in GC, and may serve as a novel therapeutic target for GC treatment.
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- 2018
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11. Expeditious Synthesis of 6-Fluoroalkyl-Phenanthridines via Palladium-Catalyzed Norbornene-Mediated Dehydrogenative Annulation
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Chen Chen, Han Zheng, Zhuo Wang, Xiaonan Shi, Jinghui Zhao, Dequan Jiao, Bolin Zhu, and Tongyu Li
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Annulation ,010405 organic chemistry ,Aryl ,Organic Chemistry ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Combinatorial chemistry ,0104 chemical sciences ,Catalysis ,Turn (biochemistry) ,chemistry.chemical_compound ,chemistry ,Reagent ,Electrophile ,Physical and Theoretical Chemistry ,Palladium ,Norbornene - Abstract
A novel palladium-catalyzed, norbornene-mediated intermolecular dehydrogenative annulation approach for the synthesis of 6-fluoroalkyl-phenanthridines from aryl iodides and fluorinated imidoyl chlorides, which are important structural motifs for bioactive molecules, is reported. Fluorinated imidoyl chlorides served as a new type of electrophilic reagent in the Catellani-type reaction, which, in turn, could be readily prepared from various anilines and fluorinated carboxylic acids. Control experiments were carried out to study the mechanism of the reaction. This transformation is scalable and tolerates a broad range of functional groups.
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- 2018
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12. Reactivity of Alkyne Insertion and Catalytic Activity of Five‐ and Six‐Membered Cyclometalated Phosphine Complexes of Iridium
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Siyang Xing, Bolin Zhu, Tongyu Li, Kai Liu, and Zhuo Wang
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chemistry.chemical_classification ,010405 organic chemistry ,Chemistry ,Alkyne ,chemistry.chemical_element ,Homogeneous catalysis ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Catalysis ,Inorganic Chemistry ,chemistry.chemical_compound ,Polymer chemistry ,Reactivity (chemistry) ,Iridium ,Phosphine - Published
- 2018
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13. The Hippo pathway as a drug target in gastric cancer
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Yiting Qiao, Tongyu Li, Shusen Zheng, and Hangxiang Wang
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0301 basic medicine ,Cancer Research ,Cell division ,Cellular differentiation ,Antineoplastic Agents ,Disease ,Protein Serine-Threonine Kinases ,Biology ,law.invention ,Metastasis ,03 medical and health sciences ,chemistry.chemical_compound ,Stomach Neoplasms ,law ,Lysophosphatidic acid ,medicine ,Humans ,Hippo Signaling Pathway ,Clinical Trials as Topic ,Hippo signaling pathway ,medicine.disease ,Gene Expression Regulation, Neoplastic ,Crosstalk (biology) ,030104 developmental biology ,Oncology ,chemistry ,Cancer research ,Suppressor ,Signal Transduction - Abstract
The Hippo tumor suppressor pathway is critical for balancing cellular differentiation and proliferation in response to cell-cell contact, mechanical signals and diffusible signals such as lysophosphatidic acid. Hippo pathway signaling is frequently dysregulated in gastric cancer (GC), as well as many other kinds of solid tumors, contributing to multiple aspects of malignant progression including unchecked cell division and metastasis. Considering the importance of this Hippo pathway in cancer, its pharmacological disruption may be of huge benefit in the fight against this disease. In this review, we summarize the components of the Hippo pathway, its crosstalk with other major oncogenic signaling pathways, common mechanisms of its dysregulation, as well as potential therapeutic approaches of targeting this pathway for cancer treatment, specifically in a GC context.
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- 2018
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14. Aromatic alkyne insertion into six-membered cyclometalated pyridine complexes of iridium: different insertion modes and structurally novel products
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Zhuo Wang, Xiaodan Chu, Shaowei Zhang, Tongyu Li, and Bolin Zhu
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chemistry.chemical_classification ,010405 organic chemistry ,General Chemical Engineering ,Alkyne ,chemistry.chemical_element ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Pyridine ,Methanol ,Iridium - Abstract
Reactions of 2-benzoylpyridine or 2-benzylpyridine with [Cp*MCl2]2 (M = Ir, Rh) have been carried out in the presence of NaOAc in refluxing methanol, which form the corresponding six-membered cyclometalated products (1–3) except for the reaction of 2-benzylpyridine with [Cp*RhCl2]2. Insertion reactions of two six-membered cyclometalated pyridine iridium complexes (1 and 2) with terminal or internal aromatic alkynes were studied. Terminal alkynes p-XC6H4CCH (X = H, MeO, and F) with 1 give the corresponding five- and seven-membered doubly cycloiridated complexes 4a–c, internal alkynes p-XC6H4CCC6H4X-p (X = H, MeO, and Br) form the similar five- and seven-membered doubly cycloiridated complexes (5a,b) and/or di-insertion products (6a,c), whereas the acyl alkyne PhCCCOPh affords the novel spiro-metalated complex 7. For complex 2, internal alkynes p-XC6H4CCC6H4X-p (X = H, MeO, and Br) form similar five- and seven-membered doubly cycloiridated complexes (8a–c). However, in the case of PhCCCOPh, the reaction gives the novel four-membered cyclometalated complex 9. These results suggest that the products formed by alkyne insertion reactions of the six-membered cycloiridated pyridine complexes are very diverse. Plausible pathways for the formation of these novel insertion products were proposed. Molecular structures of seven cyclometalated complexes were determined by X-ray diffraction.
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- 2018
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15. Akt inhibition improves the efficacy of cabazitaxel nanomedicine in preclinical taxane-resistant cancer models
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Jianqin Wan, Xiaoxiao Hu, Wanzhi Chen, Tongyu Li, Xiaona Chen, and Hangxiang Wang
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Taxane ,business.industry ,Pharmaceutical Science ,Cancer ,Antineoplastic Agents ,Drug resistance ,medicine.disease ,Efficacy ,chemistry.chemical_compound ,Nanomedicine ,Paclitaxel ,chemistry ,Docetaxel ,Drug Resistance, Neoplasm ,Cabazitaxel ,Neoplasms ,Cancer cell ,Cancer research ,Animals ,Humans ,Medicine ,Taxoids ,business ,Proto-Oncogene Proteins c-akt ,medicine.drug - Abstract
Background: Drug resistance continues to be a major clinical challenge in achieving cures in cancer patients. Cabazitaxel has shown the ability to surmount drug resistance through bypassing the transporter-mediated drug expulsion; however, the substantially high toxicity in patients hampered its clinical application. In addition, upregulation of certain self-defense proteins (e.g, Akt) was reportedly involved in drug resistance, which may further compromise the activity of cabazitaxel. We have previously developed several prodrug-based strategies to deliver nanoparticles encapsulating cabazitaxel derivatives in tumors with enhanced efficacy and improved in vivo tolerability. Therefore, we hypothesized that combing cabazitaxel nanotherapeutics with a pan-Akt inhibitor MK-2206 would synergistically eliminate the resistant cancers with reduced systemic toxicity.Methods: Activation of Akt in resistant cancers upon cabazitaxel treatment was determined by western blotting assay. The effect of combing MK-2206 with cabazitaxel on cell viability was evaluated by CCK-8 assay. To improve the in vivo biocompatibility, the delivery of potent cabazitaxel was feasibly achieved via the integration of oligolactide-conjugated cabazitaxel into the PEG-b-PLA matrix. Both the synergism and safety of cabazitaxel nanomedicine-based combination were evaluated through a series of in vitro and in vivo experiments, including Western blotting assay, CCK-8 assay, EdU assay, flow cytometry, migration assay, transwell assay, MTD study, myelosuppression study, nude mouse xenograft, and immunostaining analyses. Results: We found that resistant cells adapted to activate Akt signaling upon cabazitaxel treatment, which potentially discounts the efficacy of cabazitaxel. The addition of MK-2206 reversed this situation and potentiated the activity of cabazitaxel nanomedicine against resistant cells. Mechanistically, suppression of the Akt pathway increased the microtubule-stabilizing effect of cabazitaxel. Their collaboration was demonstrated to maximize the efficacy in a xenograft model bearing paclitaxel-resistant tumors. In particular, the nanoformulation substantially improved drug tolerability in animals, and combined treatment with MK-2206 was proven to be safe for synergistic cancer therapy. Conclusion: The preclinical studies demonstrate the therapeutic efficacy of our binary system consisting of a better-tolerated nanotherapy and a specific pathway modulator against resistant cells, thereby highlighting the potential applications for the clinical treatment of patients with multidrug-resistant malignancies.
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- 2021
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16. ZNF830 mediates cancer chemoresistance through promoting homologous-recombination repair
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Xiaorui Shi, Liqian Zhou, Tongyu Li, Wei Liu, Hangxiang Wang, Tian Xie, Jianqin Wan, Xu Liu, Yiting Qiao, Guo Chen, Yaru Shi, Fu Wang, Qi Zeng, Hui Xie, Jianxiang Chen, and Youwei Sun
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0301 basic medicine ,Genome instability ,Lung Neoplasms ,DNA damage ,Kruppel-Like Transcription Factors ,Regulator ,Mice, Nude ,Antineoplastic Agents ,Ataxia Telangiectasia Mutated Proteins ,Genome Integrity, Repair and Replication ,Biology ,Genomic Instability ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Stomach Neoplasms ,Cell Line, Tumor ,Genetics ,medicine ,Animals ,Humans ,Hydroxyurea ,DNA Breaks, Double-Stranded ,Phosphorylation ,Zinc finger ,Binding Sites ,Endodeoxyribonucleases ,Osteoblasts ,Nuclear Proteins ,Recombinational DNA Repair ,Cancer ,Epithelial Cells ,DNA, Neoplasm ,medicine.disease ,Survival Analysis ,Xenograft Model Antitumor Assays ,030104 developmental biology ,chemistry ,Drug Resistance, Neoplasm ,Cancer cell ,Cancer research ,Camptothecin ,Female ,Carrier Proteins ,Homologous recombination ,DNA ,Protein Binding - Abstract
Homologous recombination (HR), which mediates the repair of DNA double-strand breaks (DSB), is crucial for maintaining genomic integrity and enhancing survival in response to chemotherapy and radiotherapy in human cancers. However, the mechanisms of HR repair in treatment resistance for the improvement of cancer therapy remains unclear. Here, we report that the zinc finger protein 830 (ZNF830) promotes HR repair and the survival of cancer cells in response to DNA damage. Mechanistically, ZNF830 directly participates in DNA end resection via interacting with CtIP and regulating CtIP recruitment to DNA damage sites. Moreover, the recruitment of ZNF830 at DNA damage sites is dependent on its phosphorylation at serine 362 by ATR. ZNF830 directly and preferentially binds to double-strand DNA with its 3′ or 5′ overhang through the Zinc finger (Znf) domain, facilitating HR repair and maintaining genome stability. Thus, our study identified a novel function of ZNF830 as a HR repair regulator in DNA end resection, conferring the chemoresistance to genotoxic therapy for cancers those that overexpress ZNF830.
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- 2017
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17. The Expression of the Δ6 Fatty Acyl Desaturase-Like Gene from Pacific White Shrimp (Litopenaeus vannamei) Under Different Salinities and Dietary Lipid Compositions
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Erchao Li, Jian G. Qin, Ke Chen, Chang Xu, Tongyu Li, Liqiao Chen, and Zhixin Xu
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0301 basic medicine ,biology ,Linoleic acid ,Dietary lipid ,Litopenaeus ,Scylla paramamosain ,Aquatic Science ,Portunus trituberculatus ,biology.organism_classification ,Shrimp ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Fatty acid desaturase ,chemistry ,Biochemistry ,biology.protein ,Hepatopancreas - Abstract
The synthesis of highly unsaturated fatty acids (HUFAs) from C18 fatty acids in the Pacific white shrimp, Litopenaeus vannamei, has long been debated in terms of the limited capacity or even the existence of fatty acid desaturase and elongase. In the present study, a Δ6 fatty acyl desaturase (Fad)-like gene was identified and characterized with a full length of 1,491 bp, including a 39-bp 5′-UTR (untranslated region), a 108-bp 3′-UTR, and a 1,344 bp open reading frame encoding a 448 amino acid protein. The protein contained a cytochrome b5-like heme/steroid binding domain and a Fad domain. The Δ6 Fad-like protein of L. vannamei shared 70%–77% sequence homology with those of Macrobrachium nipponense, Scylla paramamosain, Portunus trituberculatus and Eriocheir sinensis. When salinity was reduced from 30 to 3, Δ6 Fad-like gene expression significantly increased in the gills, muscles, eyestalk, and hepatopancreas (P < 0.05). The highest expression was observed in the hepatopancreas under salinity 3 i...
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- 2017
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18. Cover Feature: New Organometallic Ruthenium(II) Compounds Synergistically Show Cytotoxic, Antimetastatic and Antiangiogenic Activities for the Treatment of Metastatic Cancer (Chem. Eur. J. 66/2020)
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Mohamed Kasim Mohamed Subarkhan, Chao Chen, Yuchen Wang, Hangxiang Wang, Jiahui Jin, Tongyu Li, Siming Lu, and Liwei Shu
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Cancer chemotherapy ,Chemistry ,Organic Chemistry ,Cancer ,chemistry.chemical_element ,General Chemistry ,medicine.disease ,Catalysis ,Ruthenium ,Feature (computer vision) ,medicine ,Cancer research ,Cytotoxic T cell ,Cover (algebra) ,Cytotoxicity - Published
- 2020
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19. Novel NHC-coordinated ruthenium(II) arene complexes achieve synergistic efficacy as safe and effective anticancer therapeutics
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Chang Xu, Chao Chen, Tongyu Li, Siming Lu, Fangzhou Luo, and Hangxiang Wang
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Cell cycle checkpoint ,Cell ,Intracellular Space ,Antineoplastic Agents ,Apoptosis ,01 natural sciences ,Ruthenium ,Mice ,Structure-Activity Relationship ,03 medical and health sciences ,Coordination Complexes ,Heterocyclic Compounds ,Cell Line, Tumor ,Drug Discovery ,medicine ,Animals ,Humans ,Cytotoxic T cell ,Neoplasm Metastasis ,030304 developmental biology ,Pharmacology ,Cisplatin ,0303 health sciences ,Dose-Response Relationship, Drug ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Benzene ,Drug Synergism ,General Medicine ,Xenograft Model Antitumor Assays ,0104 chemical sciences ,Cell killing ,medicine.anatomical_structure ,Tumor progression ,Cancer cell ,Cancer research ,Safety ,Reactive Oxygen Species ,medicine.drug - Abstract
There is an urgent need for more effective, less toxic cancer therapy agents. Motivated by this need, we synthesized a small panel of N-heterocyclic carbene (NHC)-coordinated ruthenium(II) arene complexes Ru1–Ru6 with the formula [Ru(p-cymene)(L)Cl]PF6 (L = NHC ligand with varying substituents). Cell-based in vitro studies revealed that despite the structural similarity, Ru1–Ru6 exhibited distinct cytotoxic activities against cancer cells. In particular, Ru4 and Ru6, which bear n-octyl and pentamethylbenzyl motifs, respectively, were the most active at inducing apoptosis. In human ovarian A2780 cancer cells, Ru4 and Ru6 showed the highest cytotoxicities with IC50 values of 2.74 ± 0.15 μM and 1.98 ± 0.10 μM, respectively, and they were approximately 2-fold more potent than cisplatin (IC50 = 5.55 ± 0.37 μM). In addition to the cell killing capacity, inhibition of cell migration was validated by using these two optimized complexes. Mechanistic studies revealed that Ru4 and Ru6 complexes induced apoptosis in a caspase-dependent manner, primarily through intracellular reactive oxygen species (ROS) overproduction and cell cycle arrest at G1 phase. Furthermore, in a preclinical metastatic model of A2780 tumor xenograft, administration of Ru4 and Ru6 (20 μmol/kg) resulted in a marked inhibition of tumor progression and metastasis. Finally, a substantially alleviated systemic toxicity was observed for both complexes in comparison with cisplatin in animals. Overall, this study greatly increases our understanding of NHC-coordinated Ru(II) arene metallodrugs, aiding further investigation of their therapeutic potential in the treatment of metastatic cancers.
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- 2020
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20. Chemical Derivatization of the Anticancer Agent Cabazitaxel Using a Polyunsaturated Fatty Acid for Safe Drug Delivery
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Zhongjie Lu, Yiting Qiao, Jianqin Wan, Tongyu Li, Jiaping Wu, Liqian Zhou, Hangxiang Wang, Shusen Zheng, Haiyang Xie, and Lulu Ren
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0301 basic medicine ,Drug ,030103 biophysics ,media_common.quotation_subject ,Biomedical Engineering ,Pharmaceutical Science ,Medicine (miscellaneous) ,Bioengineering ,Antineoplastic Agents ,Pharmacology ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,Drug Delivery Systems ,In vivo ,medicine ,Animals ,Humans ,General Materials Science ,Derivatization ,media_common ,chemistry.chemical_classification ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,chemistry ,Tolerability ,Cabazitaxel ,Drug delivery ,Fatty Acids, Unsaturated ,Taxoids ,medicine.drug ,Polyunsaturated fatty acid ,Conjugate - Abstract
The utilization of nonionic surfactants is a practical way to formulate hydrophobic chemotherapeutics, facilitating the clinical translation of drug candidates during the development process. However, since the drug toxicity in patients is primarily determined by the cytotoxic drugs themselves, such a formulation approach is unable to improve the drug tolerability. Therefore, additional strategies for enhancing drug safety profiles are necessary when considering the use of surfactants as formulation excipients. Using cabazitaxel as a target agent, we show that the miscibility of α-linolenic acid (LNA)tethered cabazitaxel conjugate 1 with polysorbate 80 (Tween 80) was enhanced. Upon further blending with aqueous solutions, conjugate 1 formed stable colloidal nanoemulsions with Tween 80. Thus, the nanoemulsions are systemically injectable and suitable for preclinical studies. Compared with parent cabazitaxel, conjugate 1 displayed a substantial improvement in its safety profile in animals. Therapeutic studies in a mouse xenograft model of human cancer further demonstrated the effectiveness of conjugate 1 in suppressing tumor growth. These results suggest that attaching flexible lipid chains to the highly toxic cabazitaxel generates a new drug entity that is more compatible with Tween 80-based formulations than its free drug form. This new entity retains its antitumor activity while improving its tolerability in vivo.
- Published
- 2018
21. Comparative transcriptome analysis reveals molecular strategies of oriental river prawn Macrobrachium nipponense in response to acute and chronic nitrite stress
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Ke Chen, Jinyun Ye, Zhixin Xu, Erchao Li, Jianguang Qin, Tongyu Li, Zhili Ding, and Liqiao Chen
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0301 basic medicine ,Arginine ,Aquatic Science ,Biology ,Serine ,Transcriptome ,03 medical and health sciences ,chemistry.chemical_compound ,Stress, Physiological ,Lysosome ,medicine ,Animals ,Environmental Chemistry ,Nitrite ,Nitrites ,Sequence Analysis, RNA ,Gene Expression Profiling ,General Medicine ,Metabolism ,030104 developmental biology ,medicine.anatomical_structure ,Gene Expression Regulation ,chemistry ,Biochemistry ,Glycine ,Palaemonidae ,Macrobrachium nipponense - Abstract
Macrobrachium nipponense is an economically and nutritionally important species threatened by ambient superfluous nitrite. De novo RNA-Seq was used to explore the molecular mechanism in M. nipponense exposed to the acute nitrite stress (26.05 mg/L nitrite-N) for 24 h and the chronic nitrite stress (1.38 mg/L nitrite-N) for 28 d A total of 175.13 million reads were obtained and assembled into 58,871 unigenes with an average length of 1028.7 bp and N50 of 1294 bp. Under the acute and chronic nitrite stress trials, 2824 and 2610 unigenes were significantly expressed. In GO analysis and KEGG pathway analysis, 30 pathways were significantly different between the two treatments while four pathways were in common and the markedly altered pathways were divided into four sections as immunity, metabolism, cell and others. The immunity section revealing the different depth of immunity provoked by nitrite stress contained the most pathways including the important pathways as phagosome, folate biosynthesis, glycerolipid metabolism, glycine, serine and threonine metabolism, amino sugar and nucleotide sugar metabolism under the acute nitrite stress, and lysosome, alanine, aspartate and glutamate metabolism, arginine and proline metabolism under the chronic nitrite stress. This is the first report of responses of M. nipponense under acute and chronic nitrite stress through de novo transcriptome sequencing on the transcriptome level. The results of transcriptome analysis improve our understanding on the underlying molecular mechanisms coping with nitrite stress in crustacean species.
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- 2016
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- View/download PDF
22. Response of gut health and microbiota to sulfide exposure in Pacific white shrimp Litopenaeus vannamei
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Erchao Li, Yantong Suo, Jian G. Qin, Zhimin Gu, Yongyi Jia, Liqiao Chen, and Tongyu Li
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0301 basic medicine ,Sulfide ,Litopenaeus ,Gene Expression ,Aquatic Science ,Sulfides ,Microbiology ,Arthropod Proteins ,03 medical and health sciences ,chemistry.chemical_compound ,Immune system ,Penaeidae ,Environmental Chemistry ,Animals ,Shellfish ,chemistry.chemical_classification ,Androstenols ,biology ,fungi ,Aquatic animal ,04 agricultural and veterinary sciences ,General Medicine ,biology.organism_classification ,Immunity, Innate ,Shrimp ,Gastrointestinal Microbiome ,Gastrointestinal Tract ,030104 developmental biology ,chemistry ,040102 fisheries ,0401 agriculture, forestry, and fisheries ,Tumor necrosis factor alpha ,Water Pollutants, Chemical ,Toxicant - Abstract
Sulfide is a natural and widely distributed toxicant. It can be commonly found on the interface between water and sediment in the aquatic environment. The Pacific white shrimp Litopenaeus vannamei starts life in the benthic zone soon after the mysis stage, an early stage of post larvae. Therefore, L. vannamei is inevitably affected by exposure to sulfide released from pond sediment. This study explored the toxicant effect of different concentrations of sulfide on the intestinal health and microbiota of Pacific white shrimp by monitoring the change of expression of inflammatory, immune related cytokines, and the structure of the intestinal microbiota. The gut histology, expressions of inflammatory and immune related cytokines (tumor necrosis factor-alpha, C-type lectin 3, myostatin and heat shock transcription factor 1), and the microbiota were determined in L. vannamei after exposure to 0 (control), 425.5 (1/10 LC 50-96 h), and 851 μg/L (1/5 LC 50-96 h) of sulfide for 21 days. With the increase of sulfide concentration, intestinal injury was aggravated and the inflammatory and immune related cytokines generated a range of reactions. The expression of myostatin (MSTN) was significantly down-regulated by the concentration of sulfide exposure. No difference in the expression of heat shock transcription factor 1 (HSF1) was found between the control and shrimp exposed to 425.5 μg/L, but significantly higher HSF1 expression was found in shrimp exposed to 851 μg/L of sulfide. Significantly higher values of tumor necrosis factor-alpha (TNF-α) and C-type lectin 3 (CTL3) were found in the shrimp exposed to 425.5 μg/L of sulfide compared to the control, but a lower value was found in the shrimp exposed to 851 μg/L (P 0.05). Sulfide also changed the intestinal microbial communities. The abundance of pathogenic bacteria, such as Cyanobacteria, Vibrio and Photobacterium, increased significantly with exposure to the increasing concentration of sulfide. The abundance of some anti-stress bacteria, such as Chlorobi and Fusobacterium, increased. Nitrospirae which can alleviate nitrite toxicity decreased. Microbacterium, Parachlamydia, and Shewanella were all commonly found and down-regulated in both sulfide groups, which is associated with an adaptation to sulfide stimulation. This study indicates that chronic exposure to sub-lethal levels of sulfide could lead to damage of the gut structure, stimulate the response of the inflammatory and immune systems, and shape the structure of the gut microbiota in L. vannamei.
- Published
- 2016
23. Energy metabolism and metabolomics response of Pacific white shrimp Litopenaeus vannamei to sulfide toxicity
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Yantong Suo, Yongyi Jia, Erchao Li, Liqiao Chen, Zhixin Xu, Jian G. Qin, Tongyu Li, and Zhimin Gu
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0301 basic medicine ,Blood Glucose ,Sulfide ,Health, Toxicology and Mutagenesis ,Carboxylic Acids ,Hepatopancreas ,010501 environmental sciences ,Aquatic Science ,Biology ,Sulfides ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Penaeidae ,Animals ,Metabolomics ,Amino Acids ,Chronic toxicity ,0105 earth and related environmental sciences ,chemistry.chemical_classification ,L-Lactate Dehydrogenase ,Muscles ,Tricarboxylic acid ,biology.organism_classification ,Shrimp ,Lactic acid ,030104 developmental biology ,chemistry ,Biochemistry ,Succinic acid ,Pyruvic acid ,Energy Metabolism ,Glycogen ,Water Pollutants, Chemical - Abstract
The toxicity and poisoning mechanisms of sulfide were studied in Litopenaeus vannamei from the perspective of energy metabolism and metabolomics. The lethal concentrations of sulfide in L. vannamei (LC50) at 24 h, 48 h, 72 h, and 96 h were determined. Sulfide at a concentration of 0, 1/10 (425.5 μg/L), and 1/5 (851 μg/L) of the LC50 at 96 h was used to test the metabolic responses of L. vannamei for 21 days. The chronic exposure of shrimp to a higher sulfide concentration of 851 μg/L decreased shrimp survival but did not affect weight gain or the hepatopancreas index. The glycogen content in the hepatopancreas and muscle and the activity of hepatopancreas cytochrome C oxidase of the shrimp exposed to all sulfide concentrations were significantly lower, and the serum glucose and lactic acid levels and lactic acid dehydrogenase activity were significantly lower than those in the control. Metabolomics assays showed that shrimp exposed to sulfide had lower amounts of serum pyruvic acid, succinic acid, glycine, alanine, and proline in the 425.5 μg/L group and phosphate, succinic acid, beta-alanine, serine, and l-histidine in the 851 μg/L group than in the control. Chronic sulfide exposure could disturb protein synthesis in shrimp but enhance gluconeogenesis and substrate absorption for ATP synthesis and tricarboxylic acid cycles to provide extra energy to cope with sulfide stress. Chronic sulfide exposure could adversely affect the health status of L. vannamei, as indicated by the high amounts of serum n-ethylmaleamic acid, pyroglutamic acid, aspartic acid and phenylalanine relative to the control. This study indicates that chronic exposure of shrimp to sulfide can decrease health and lower survival through functional changes in gluconeogenesis, protein synthesis and energy metabolism.
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- 2016
24. Molecular characterization and expression of AMP-activated protein kinase in response to low-salinity stress in the Pacific white shrimp Litopenaeus vannamei
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Jianguang Qin, Tongyu Li, Xiaodan Wang, Liqiao Chen, Shifeng Wang, Erchao Li, Chang Xu, Ke Chen, and Zhixin Xu
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0301 basic medicine ,Salinity ,Time Factors ,Transcription, Genetic ,Physiology ,AMP-Activated Protein Kinases ,Biochemistry ,Gene Expression Regulation, Enzymologic ,03 medical and health sciences ,AMP-activated protein kinase ,Penaeidae ,Stress, Physiological ,Gene expression ,Animals ,Humans ,Amino Acid Sequence ,Protein kinase A ,Molecular Biology ,chemistry.chemical_classification ,Messenger RNA ,biology ,AMPK ,04 agricultural and veterinary sciences ,Metabolism ,biology.organism_classification ,Amino acid ,Rats ,030104 developmental biology ,chemistry ,Organ Specificity ,040102 fisheries ,biology.protein ,0401 agriculture, forestry, and fisheries ,Hepatopancreas ,Cattle ,Energy Metabolism - Abstract
AMP-activated protein kinase (AMPK) serves as a major regulator of cellular energy metabolism by activating ATP production pathways and blocking ATP consumption. However, information on AMPK genes in aquatic animals is limited. In this study, three subunits of AMPK were cloned from the Pacific white shrimp Litopenaeus vannamei. The full-length cDNAs of the α, β and γ subunits were 1617, 1243 and 3467bp long, respectively, with open reading frames of 1566, 873 and 2988bp encoding for 521, 290 and 996 amino acids, respectively. Amino acid sequence alignments of the three subunits showed that the functional domains in the L. vannamei proteins retained the highest similarity with those of other animals, at 89%, 58%, and 75%, respectively. The expression levels of the three subunits were higher in the muscle and gills than in the eyestalk and hepatopancreas. The mRNA levels of AMPK-α and AMPK-β were up-regulated in the hepatopancreas and muscle after acute low-salinity stress at 3psu for 6h compared with control salinity at 20psu. After 8-week salinity stress at 3psu, AMPK-α and AMPK-β mRNA levels in the hepatopancreas were significantly higher than those of the control at 30psu. However, in the muscle only AMPK-γ mRNA was significantly up-regulated at low salinity relative to controls. Muscle and hepatopancreas showed increases in AMPK protein after 6h exposure to low salinity, but there were no differences seen after long term acclimation. The change patterns of protein were slightly differing from the mRNA patterns due to the distinguishing function of individual subunits of AMPK. These findings confirm that three AMPK subunits are present in L. vannamei and that all encode proteins with conserved functional domains. The three AMPK subunits are all regulated at the transcriptional and protein levels to manage excess energy expenditure during salinity stress.
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- 2016
25. Photodetectors Based on Micro-nano Structure Material
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Yu Yu, Wuyue Wang, Weihua Li, Gong Wang, Yulei Wang, Zhiwei Lu, Sensen Li, Wanli Zhao, Yuhai Li, Tongyu Liu, and Xiusheng Yan
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photodetector ,micro-nano structure ,performance ,fabrication ,applications ,Chemistry ,QD1-999 - Abstract
Photodetectors converting optical signals into electrical signals have been widely utilized and have received more and more attention in scientific research and industrial fields including optical interconnection, optical communication, and environmental monitoring. Herein, we summarize the latest development of photodetectors with different micro-nano structures and different materials and the performance indicators of photodetectors. Several photodetectors, such as flexible, ultraviolet two-dimensional (2D) microscale, and dual-band photodetectors, are listed in this minireview. Meanwhile, the current bottleneck and future development prospects of the photodetector are discussed.
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- 2022
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26. Graphene Passively Q-Switched Nd:YAG Laser by 885 nm Laser Diode Resonant Pumping
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Liwei Xu, Yingyi Li, Jun Cai, Wanli Zhao, Tongyu Liu, Tongyu Dai, Youlun Ju, and Yu Ding
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Nd:YAG ,passively Q-switched ,graphene ,resonant pumping ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
A graphene passively Q-switched Nd:YAG laser experienced resonant pumping by an 885 nm laser diode (LD), as demonstrated in this paper. In the continuous-wave operation, the maximum average output power was up to 1.8 W with the absorbed pump power being 11.7 W, and the slope efficiency was 51.2%. In the Q-switching operation, the maximum average output power was up to 639 mW with a pulse width of 2.06 μs at the repetition frequency of 102.7 kHz, while the slope efficiency and the beam quality factor M2 were 25.3% and 1.25, respectively.
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- 2022
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27. A Diode Pumped Middle Infrared Laser Based on Ho: GdVO4 Crystal
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Yu Ding, Tongyu Liu, and Mengmeng Yan
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middle infrared band ,diode-pumped laser ,Ho: GdVO4 crystal ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Ho: GdVO4 crystal is the host material for the production of laser working in the middle infrared range. In this contribution, the characteristic parameters of the Ho: GdVO4 crystal were measured, and the material was used as a gain medium to build a diode-pumped laser for the first time, to reach a laser output at 2047.9 nm. The output beam quality factor M2 was measured to be 1.4 and 1.3 in x-direction and y-direction, respectively. In addition, the influence of the transmittance of the output mirror on the generation of laser was obtained through exploration. The results showed that the laser wavelength blue-shifted as the output transmittance increased.
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- 2021
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28. Tailorable Brillouin Light Scattering in a Lithium Niobate Waveguide
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Wuyue Wang, Yu Yu, Yunfei Li, Zhenxu Bai, Gong Wang, Kai Li, Changyu Song, Zhiyong Wang, Sensen Li, Yulei Wang, Zhiwei Lu, Yuhai Li, Tongyu Liu, and Xiusheng Yan
- Subjects
stimulated Brillouin scattering ,lithium niobate ,tunable phonon frequency ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Stimulated Brillouin scattering (SBS) lasers based on silicon waveguides with large SBS gain have been widely used in frequency tunable laser emissions, mode-locked pulse lasers, low-noise oscillators, optical gyroscopes and other fields. However, among SBS lasers, the realization of Brillouin laser output often requires a longer waveguide length, which not only increases waveguide loss but also increase the size of the device. As a new medium, lithium niobate has been fabricated into a new type of hybrid structure. Meanwhile, the width of a suspended waveguide is adjusted to tune the phonon frequency of an SBS laser based on lithium niobate substrate. Simulation results show that the tunable forward SBS effect is realized in a lithium niobate-suspended optical waveguide, showing a larger forward stimulated Brillouin scattering gain of 0.31 W−1m−1. The tunable phonon frequency ranges from 1 to 15 GHz. Therefore, utilizing the photon–phonon conversion effect, the waveguide system with LiNbO3 will pave a new way forward with better integration.
- Published
- 2021
- Full Text
- View/download PDF
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