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Recent advances in polyoxometalates acid-catalyzed organic reactions

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Chinese Chemical Letters 2023年第5期34卷 143-154页

作者： yu-feng liu Chang-Wen Hu Guo-Ping Yang Jiangxi Province Key Laboratory of Synthetic Chemistry Jiangxi Key Laboratory for Mass Spectrometry and InstrumentationEast China University of TechnologyNanchang 330013China Key Laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Polyoxometalates(POMs)have conducive properties such as controlled Bronsted and Lewis acidity,high thermal stability,nontoxic nature,tunable solubility,and less *** have been extensively applied in catalytic organic reactions and have an exciting prospect for industrial *** review summarized recent progress in the application of POMs as acid catalysts for various organic reactions including C-C bond formation,C-N bond formation,C-O bond formation,heterocyclic synthesis reactions,cyanosilylation and hydrolysis *** POMs catalysts including heteropoly acids(HPAs)and cationic functionalized HPAs with Bronsted acidity,HPAs supported on non-precious metal support with Bronsted acidity(or both Bronsted and Lewis acidity),transition metal substituted POMs with Lewis acidity were applied in above *** review attempts to provide up-to-date information about POMs acid-catalyzed organic reactions and propose future prospects.

关键词： Polyoxometalates Acid catalysis C-C bond formation C-N bond formation C-O bond formation Heterocyclic synthesis Cyanosilylation and hydrolysis reactions

Clinicopathological and immunohistochemical analysis of gastrointestinal stromal tumor

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World Journal of Gastroenterology 2006年第26期12卷 4161-4165页

作者： feng-yu liu Ji-Ping Qi feng-Lin Xu Ai-Ping Wu Department of Research Harbin Medical University Harbin 150086 Heilongjiang Province China Department of Pathology First Hospital of Harbin Medical University Harbin 150001 Heilongjiang Province China

AIM： To investigate the clinicopathological features of gastrointestinal stromal tumor （GIST） and to study the reference indexes for malignancy. METHODS： Fifty-two cases of primary GIST were distinguished from a group of gastrointestinal mesenchymal tumors using a panel of antibodies such as CD117 and CD34 by immunohistochemical SP method. Their biological behaviors were analyzed using the expression of p21WAF1 and Bax in 52 cases of GIST. RESULTS： Grossly, the tumor size was between 1.5 cm and 13 cm （mean： 5.5 cm）. Focal areas of hemorrhage, necrosis, or small cyst formation could be seen. Microscopically, the tumor was composed of spindle cells （20 cases）, epithelioid cells （20 cases） and mixed cells （12 cases）. Immunohistochemically, CDl17 and CD34 showed diffuse strong positive expressions, the positive rates were 98.1% and 92.3%. SMA, S-100, NSE, NF and MBP showed focal positive expressions, the positive rates were 48.1%, 28.8%, 25%, 21.2% and 42.3% respectively. Vimentins were all positive desmin and CgA were all negative. In normal adult stomach and intestine, the immunoreactive staining for CD117 and CD34 showed immunoreactive interstitial cells of Cajal in myenteric neuroplexus. Among the 52 cases of GIST, 27 were positive for p21WAF1 （51.9%）, 29 for Bax （55.8%）. The expression of p21WAF1 and Bax had no significent difference with the localization, size, histological subtype of GIST, but had a significent difference with the histological grade （P = 0.000, respectively）, p21WAF1 expression had a positive correlation to Bax expression （r = 0.461, P = 0.001, k = 0.459）. CONCLUSION： GIST has complicated arrangements and various cell types. Positivity of CD117 and CD34 is the most valuable factor in diagnosing GIST. Expression of p21WAF1 and Bax plays an important role in potential malignancy and malignancy rather than in benign GIST. p21WAF1 and Bax may be used as the markers in the assessment of GIST malignant potential.

关键词： Gastrointestinal stromal tumor p21WAF1 Bax

Scapular bone grafting with allograft pin fixation for repair of bony Bankart lesions: A biomechanical study

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World Journal of Clinical Cases 2021年第32期9卷 9783-9791页

作者： Ming Lu Hai-Peng Li yu-Jie liu Xue-Zhen Shen feng Gao Bo Hu yu-feng liu Medical School of Chinese PLA Beijing 100853China The Fourth Comprehensive Service and Support Center The PLA Beijing Administration of Veterans Service Affairs DepartmentBeijing 100191China Department of Orthopedics The Fourth Medical CenterChinese PLA General HospitalBeijing 100853China Capital Medical University Beijing Luhe Hospital Beijing 100000China National Institute of Sports Medicine Beijing 100000China The Second Department of Orthopedics Beijing Chaoyang Integrative Medicine Emergency Medical CenterBeijing 100022China

BACKGROUND Severe bony Bankart lesions are a difficult challenge in clinical treatment and *** current treatment methods consist mostly of Latarjet-Bristow surgery and its modified *** good results have been achieved,there are also complications such as coracoid fracture,bone graft displacement,and vascular and nerve *** To analyze the techniques and biomechanical properties of transversely fixing a bone block from the scapular spine using bone allograft pins with suture threads to repair bony Bankart *** Fresh human shoulder joint specimens and a cadaver specimen model for scapular bone grafting with allograft pin fixation for repair of bony Bankart lesions were *** the humeral rotation angles were 0°,30°,60°and 90°,and the axial loads were 30 N,40 N,and 50 N,the humerus displacement was studied by biomechanical *** When the angle of external rotation of the humerus was 0°,30°,60°,and 90°,with axial loads of 30 N,40 N,and 50 N,the data of the normal control group,allograft pin repair group,and titanium alloy hollow screw repair group were compared with each other by the q-test,which showed that there were no statistically differences among the three groups(P>0.05).CONCLUSION The joints repaired with bone block from the scapular spine transversely fixed with allograft bony pins to repair bony Bankart lesions show good mechanical *** bone block has similar properties to normal glenohumeral joints in terms of biomechanical stability.

关键词： Bankart lesion Scapular spine Allograft bone Biomechanical

Elevated Neurosteroids in the Lateral Thalamus Relieve Neuropathic Pain in Rats with Spared Nerve Injury

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Neuroscience Bulletin 2016年第4期32卷 311-322页

作者： Meng Zhang Jia liu Meng-Meng Zhou Honghai Wu Yanning Hou yun-feng Li yuxin Yin Lemin Zheng feng-yu liu Ming Yi You Wan Neuroscience Research Institute Peking UniversityBeiiing 100191 China Institute of Systems Biomedicine Peking UniversityBeijing 100191 China Department of Pharmacy Bethune International PeaceHospital Shijiazhuang Shijiazhuang 050082 China Department of New Drug Evaluation Beijing Institute ofPharmacology and Toxicology Beijing 100007 China Institute of Cardiovascular Sciences and Institute of SystemsBiomedicine and Key Laboratory of MolecularCardiovascular Sciences of the Ministry of Education PekingUniversity Beijing 100191 China Key Laboratory for Neuroscience Ministry of Education/National Health and Family Planning Commission School ofBasic Medical Sciences Peking University Beijing 100191China Department of Neurobiology School of Basic MedicalSciences Peking University Beijing 100191 China

Neurosteroids are synthesized in the nervous system from cholesterol or steroidal precursors imported from peripheral sources. These compounds are important allosteric modulators of γ-aminobutyric acid A receptors （GABAARs）, which play a vital role in pain modulation in the lateral thalamus, a main gate where somatosensory information enters the cerebral cortex. Using high-perfor mance liquid chromatography/tandem mass spectrometry, we found increased levels of neurosteroids （pregnenolone, progesterone, deoxycorticosterone, allopregnanolone, and tetrahydrodeoxycorticosterone） in the chronic stage of neuropathic pain （28 days after spared nerve injury） in *** expression of the translocator protein TSPO, the upstream steroidogenesis rate-limiting enzyme, increased at the same time. In vivo stereotaxic microinjection of neurosteroids or the TSPO activator AC-5216 into the lateral thalamus （AP -3.0 mm, ML 4-3.0 mm, DV 6.0 mm） alleviated the mechanical allodynia in neuropathic pain, while the TSPO inhibitor PK 11195 exacerbated it. The analgesic effects of AC-5216 and neurosteroids were sig- nificantly attenuated by the GABAAR antagonist bicuculline. These results suggested that elevated neurosteroids in the lateral thalamus play a protective role in the chronic stage of neuropathic pain.

关键词： Neurosteroids Translocator protein Sparednerve injury Thalamus GABAA receptors

Formaldehyde up-regulates TRPV1 through MAPK and PI3K signaling pathways in a rat model of bone cancer pain

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Neuroscience Bulletin 2012年第2期28卷 165-172页

作者： Ying Han Yan Li Xlng Xlao Jia liu Xiang-Ling Meng feng-yu liu Guo-Gang Xing You Wan Neurosczence Research Institute Department of Neurobiology School of Basic Medical Sciences Key Laboratory forNeuroscience The Ministry of Education / The Ministry of Health Peking University Beijing 100191 China

Objective Our previous study showed that tumor tissue-derived formaldehyde at low concentrations plays an important role in bone cancer pain through activating transient receptor potential vanilloid subfamily member 1 （TRPV 1）. The present study further explored whether this tumor tissue-derived endogenous formaldehyde regulates TRPV1 expres- sion in a rat model of bone cancer pain, and if so, what the possible signal pathways are during the development of this type of pain. Methods A rat model of bone cancer pain was established by injecting living MRMT-1 tumor cells into the tibia. The formaldehyde levels were determined by high performance liquid chromatography, and the expression of TRPV1 was examined with Western blot and RT-PCR. In primary cultured dorsal root ganglion （DRG） neurons, the ex- pression of TRPV1 was assessed after treatment with 100 ~tmol/L formaldehyde with or without pre-addition of PD98059 [an inhibitor for extracellular signal-regulated kinase], SB203580 （a p38 inhibitor）, SP600125 [an inhibitor for c-Jun N- terminal kinase], BIM [a protein kinase C （PKC） inhibitor] or LY294002 [a phosphatidylinositol 3-kinase （PI3K） inhibi- tor]. Results In the rat model of bone cancer pain, formaldehyde concentration increased in blood plasma, bone marrow and the spinal cord. TRPV1 protein expression was also increased in the DRG. In primary cultured DRG neurons, 100 p^mol/L formaldehyde significantly increased the TRPV1 expression level. Pre-incubation with PD98059, SB203580, SP600125 or LY294002, but not BIM, inhibited the formaldehyde-induced increase of TRPV1 expression. Conclusion Formaldehyde at a very low concentration up-regulates TRPV1 expression through mitogen-activated protein kinase and PI3K, but not PKC, signaling pathways. These results further support our previous finding that TRPV1 in peripheral after- ents plays a role in bone cancer pain.

关键词： formaldehyde TRPV1 cancer pain mitogen-activated protein kinase phosphatidylinositol 3-kinase

Formaldehyde increases intracellular calcium concentration in primary cultured hippocampal neurons partly through NMDA receptors and T-type calcium channels

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Neuroscience Bulletin 2012年第6期28卷 715-722页

作者： Ye-Nan Chi Xu Zhang Jie Cai feng-yu liu Guo-Gang Xing You Wan Neuroscience Research Institute and Department of Neurobiology Peking University Key Laboratory for Neuroscience Ministry of Education /Ministry of HealthPeking University

Objective Formaldehyde at high concentrations is a contributor to air pollution. It is also an endogenous metabolic product in cells, and when beyond physiological concentrations, has pathological effects on neurons. Formaldehyde induces mis-folding and aggregation of neuronal tau protein, hippocampal neuronal apoptosis, cognitive impairment and loss of memory functions, as well as excitation of peripheral nociceptive neurons in cancer pain models. Intracellular calcium （[Ca2＋]i） is an important intracellular messenger, and plays a key role in many pathological processes. The present study aimed to investigate the effect of formaldehyde on [Ca2＋]i and the possible involvement of N-methyl-D-aspartate receptors （NMDARs） and T-type Ca2＋ channels on the cell membrane. Methods Using primary cultured hippocampal neurons as a model, changes of [Ca2＋]i in the presence of formaldehyde at a low concentration were detected by confocal laser scanning microscopy. Results Formaldehyde at 1 mmol/L approximately doubled [Ca2＋]i. （2R）-amino-5-phosphonopentanoate （AP5, 25 μmol/L, an NMDAR antagonist） and mibefradil （MIB, 1 μmol/L, a T-type Ca2＋ channel blocker）, given 5 min after formaldehyde perfusion, each partly inhibited the formaldehyde-induced increase of [Ca：＋]i, and this inhibitory effect was reinforced by combined application of AP5 and MIB. When applied 3 min before formaldehyde perfusion, AP5 （even at 50μmol/L） did not inhibit the formaldehyde-induced increase of [Ca2＋]i, but MIB （1 μmol/L） significantly inhibited this increase by 70%. Conclusion These results suggest that formaldehyde at a low concentration increases [Ca2＋]i in cultured hippocampal neurons; NMDARs and T-type Ca2＋ channels may be involved in this process.

关键词： formaldehyde intracellular calcium neuronal activation NMDA receptors T-type calcium channels

Two sandwich-type uranyl-containing polytungstates catalyze aerobic synthesis of benzimidazoles

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Rare Metals 2024年第3期43卷 1316-1322页

作者： yu-feng liu Qi-Long Hu Xue-Jiao Chen Ke Li Pei Luo Guo-Ping Yang School of Chemistry and Material Science Jiangxi Province Key Laboratory of Synthetic ChemistryJiangxi Key Laboratory for Mass Spectrometry and InstrumentationEast China University of TechnologyNanchang330013China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen518055China

Diversified synthetic strategies are extremely important for the structural diversity of uranium-containing polyoxometalates(U-POMs)and their functional ***,two sandwich-type U-POMs were reported,which are Na_(5.6)K_(6.4)[(UO_(2))(H_(2)O)(TeW_(9)O_(33))]_(2)·21H_(2)O(UTeW_(9))and Na_(8.9)K_(2.7)H_(1.19)[K_(0.79)(UO_(2))_(2.21)(PW_(9)O_(34))_(2)]·12H_(2)O(UPW_9)using in-situ strategy and lacunary precursor strategy,***_9 shows a typical Keggin-typeopen or half-sandwich configuration.

关键词： configuration expansion sandwich

Bromination of N-phenyloxypropyl-N'-ethyl-4,4'-bipyridium in cucurbit[8]uril molecular reactor

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Chinese Chemical Letters 2017年第2期28卷 463-466页

作者： Tian-Tian Li Lan-Lan Wen Hai-Long Ji feng-yu liu Shi-Guo Sun State Key Laboratory of Fine Chemicals School of Chemistry Dalian University of Technology Key Laboratory of Xinjiang Endemic Phytomedicine Resources Ministry of Education School of Pharmacy Shihezi University

CB[n]（n= 6-8） is a family of synthetic macrocyclic host molecules composed of n glycoluril units,which can be employed as molecular reactor.N-Phenyloxypropyl-N＇-ethyl-4,4＇-bipyridium（1） was designed to form a host-guest inclusion complex with CB[n]（n = 6-8）,subsequently,the bromination reaction of 1 and its corresponding inclusion complexes was investigated in this *** the case of 1/CB[8],the folded including mode is quite helpful to acquire 1-bormination product completely through intramolecular charge transfer（ICT）,and CB[8]can provide a safe bromination environment for 1.

关键词： Cucurbituril Molecular reactor Intramolecular charge transfer(ICT) Bromination Inclusion

Electrochemiluminescence of 1,8-Naphthalimide-Modified Carbon Nitride for Cu^(2+) Detection

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Journal of Analysis and Testing 2022年第3期6卷 296-307页

作者： feng-yu liu Tong-Kai Zhang Yi-Long Zhao Hong-Xia Ning Fu-Sheng Li State Key Laboratory of Fine Chemicals School of ChemistryDalian University of TechnologyDalian 116024China State Key Laboratory of Fine Chemicals Institute of Artif cial PhotosynthesisDUT-KTH Joint Education and Research Centre on Molecular DevicesDalian University of TechnologyDalian 116024China

It is essential to screen novel luminophores and co-reactants for the development of electrochemiluminescence(ECL)*** this work,a series of 1,8-naphthalimide-modified graphitic carbon nitride(CN/1,8-NDI_(x))ECL luminophores were successfully developed for the quantitative determination of Cu^(2+)with K_(2)S_(2)O_(8)as a *** CN/1,8-NDI_(x)was immobilized on the surface of the glassy carbon electrode(GCE),a strong ECL signal could be produced(at a potential of-1.3 V ***/AgCl),which was threefold stronger than that of unmodified g-C_(3)N_(4).The intensity of ECL could be linearly quenched by Cu^(2+)over a concentration range from 5×10^(-9)to 1×10^(-4)mol/L,and with a low limit of detection(LOD)of0.86 nmol/*** results may provide a new perspective on the novel ECL platforms development.

关键词： Electrochemiluminescence Carbon nitride Quantification Cu^(2+)ion detection