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Wei Y, Bloom P, Lin D, Gu R, Wang WH. Effect of dietary K intake on apical small-conductance K channel in CCD: role of protein tyrosine kinase. Am J Physiol Renal Physiol 2001; 281:F206-12. [PMID: 11457712 DOI: 10.1152/ajprenal.2001.281.2.f206] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have used Western blot to examine the expression of cSrc protein tyrosine kinase (PTK) and protein tyrosine phosphatase (PTP)-1D in the renal cortex, and the patch-clamp technique to determine the role of PTK in mediating the effect of dietary K intake on the small-conductance K (SK) channel in the cortical collecting duct (CCD). When rats were on a K-deficient (KD) diet for 1, 3, 5, and 7 days, the expression of cSrc increased by 40, 90, 140, and 135%, respectively. In contrast, the expression of cSrc in the renal cortex from rats on a high-K (HK) diet for 1, 2, and 3 days decreased by 40, 60, and 75%, respectively. However, the protein level of PTP-1D was not significantly changed by dietary K intake. The addition of 1 microM herbimycin A increased NP(o), a product of channel number (N) and open probability (P(o)) in the CCD from rats on a normal diet or on a KD diet. The increase in NP(o) was 0.30 (normal), 0.45 (1-day KD), 0.65 (3-day KD), 1.55 (5-day KD), and 1.85 (7-day KD), respectively. Treatment of the CCD with herbimycin A from rats on a KD diet increased NP(o) per patch from the control value (0.7) to 1.4 (1-day KD), 1.6 (3-day KD), 2.6 (5-day KD), and 3.5 (7-day KD), respectively. In contrast, HK intake for as short as 1 day abolished the effect of herbimycin A. Furthermore, the expression of ROMK channels in the renal cortex was the same between rats on a KD diet or on a HK diet. Moreover, treatment with herbimycin A did not further increase NP(o) in the CCDs from rats on a HK diet. We conclude that dietary K intake plays a key role in regulating the activity of the SK channels and that PTK is involved in mediating the effect of the K intake on channel activity in the CCD.
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Kao W, Gu R, Jia Y, Wei X, Fan H, Harris J, Zhang Z, Quinn J, Morand EF, Yang YH. A formyl peptide receptor agonist suppresses inflammation and bone damage in arthritis. Br J Pharmacol 2014; 171:4087-96. [PMID: 24824742 PMCID: PMC4243981 DOI: 10.1111/bph.12768] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 03/20/2014] [Accepted: 04/28/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND PURPOSE Annexin A1 (AnxA1) is an endogenous anti-inflammatory protein and agonist of the formyl peptide receptor 2 (FPR2). However, the potential for therapeutic FPR ligands to modify immune-mediated disease has been little explored. We investigated the effects of a synthetic FPR agonist on joint disease in the K/BxN model of rheumatoid arthritis (RA) and RA fibroblast-like synoviocytes (FLS). EXPERIMENTAL APPROACH Arthritis was induced by injection of K/BxN serum at day 0 and 2 in wild-type (WT) or AnxA1(-/-) mice and clinical and histopathological manifestations measured 8-11 days later. WT mice were given the FPR agonist compound 43 (Cpd43) (6 or 30 mg·kg(-1) i.p.) for 4 days. Effects of AnxA1 and Cpd43 on RANKL-induced osteoclastogenesis were assessed in RAW 264.7 cells and human RA FLS and macrophages. KEY RESULTS Treatment with Cpd43 before or after the onset of arthritis reduced clinical disease severity and attenuated synovial TNF-α and osteoclast-associated gene expression. Deletion of AnxA1 in mice exacerbated arthritis severity in the K/BxN model. In vitro, Cpd43 suppressed osteoclastogenesis and NFAT activity elicited by RANKL, and inhibited IL-6 secretion by mouse macrophages. In human RA joint-derived FLS and monocyte-derived macrophages, Cpd43 treatment inhibited IL-6 release, while blocking FPR2 or silencing AnxA1 increased this release. CONCLUSIONS AND IMPLICATIONS The FPR agonist Cpd43 reduced osteoclastogenesis and inflammation in a mouse model of RA and exhibited anti-inflammatory effects in relevant human cells. These data suggest that FPR ligands may represent novel therapeutic agents capable of ameliorating inflammation and bone damage in RA.
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MESH Headings
- Animals
- Annexin A1/deficiency
- Annexin A1/metabolism
- Arthritis, Experimental/drug therapy
- Arthritis, Experimental/metabolism
- Arthritis, Experimental/pathology
- Arthritis, Rheumatoid/drug therapy
- Arthritis, Rheumatoid/metabolism
- Arthritis, Rheumatoid/pathology
- Bone and Bones/drug effects
- Bone and Bones/metabolism
- Bone and Bones/pathology
- Cells, Cultured
- Disease Models, Animal
- Inflammation/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Phenylurea Compounds/administration & dosage
- Phenylurea Compounds/chemistry
- Phenylurea Compounds/pharmacology
- Pyrazoles/administration & dosage
- Pyrazoles/chemistry
- Pyrazoles/pharmacology
- Receptors, Formyl Peptide/agonists
- Receptors, Formyl Peptide/metabolism
- Structure-Activity Relationship
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Saffer LD, Gu R, Corwin JT. An RT-PCR analysis of mRNA for growth factor receptors in damaged and control sensory epithelia of rat utricles. Hear Res 1996; 94:14-23. [PMID: 8789807 DOI: 10.1016/0378-5955(95)00228-6] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Sensory epithelia from normal rat utricles and those cultured with and without neomycin treatment were assayed for the presence of growth factor receptor mRNAs by RT-PCR (reverse transcriptase-polymerase chain reaction). Both undamaged and damaged utricles showed mRNA for Insulin receptor, IGF-I receptor, FGF receptor 1, EGF receptor, and PDGF alpha receptor. Neomycin-damaged sensory epithelia showed less PDGF alpha receptor mRNA than undamaged epithelia, suggesting that this message by expressed at higher copy levels in hair cells than in supporting cells. Consistent with that hypothesis, immunohistochemistry revealed much stronger PDGF alpha receptor staining in the hair cells than in the supporting cells. Preliminary evidence suggests that IGF-I receptor message also may be lowered in neomycin-damaged epithelia.
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MESH Headings
- Animals
- Anti-Bacterial Agents/toxicity
- Base Sequence
- Chickens
- Epithelium/drug effects
- Epithelium/injuries
- ErbB Receptors/genetics
- ErbB Receptors/metabolism
- Female
- Hair Cells, Auditory/drug effects
- Hair Cells, Auditory/injuries
- Hair Cells, Auditory/metabolism
- Immunohistochemistry
- Molecular Sequence Data
- Neomycin/toxicity
- Oligonucleotide Probes
- Organ Culture Techniques
- Polymerase Chain Reaction
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, IGF Type 1/genetics
- Receptor, IGF Type 1/metabolism
- Receptor, Insulin/genetics
- Receptor, Insulin/metabolism
- Receptor, Platelet-Derived Growth Factor alpha
- Receptors, Fibroblast Growth Factor/genetics
- Receptors, Fibroblast Growth Factor/metabolism
- Receptors, Platelet-Derived Growth Factor/genetics
- Receptors, Platelet-Derived Growth Factor/metabolism
- Saccule and Utricle/drug effects
- Saccule and Utricle/injuries
- Saccule and Utricle/metabolism
- Tissue Fixation
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Wei Y, Bloom P, Gu R, Wang W. Protein-tyrosine phosphatase reduces the number of apical small conductance K+ channels in the rat cortical collecting duct. J Biol Chem 2000; 275:20502-7. [PMID: 10787405 DOI: 10.1074/jbc.m000783200] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Previous studies have demonstrated that an increase in the activity of protein-tyrosine kinase (PTK) is involved in the down-regulation of the activity of apical small conductance K(+) (SK) channels in the cortical collecting duct (CCD) from rats on a K(+)-deficient diet (). We used the patch clamp technique to investigate the role of protein-tyrosine phosphatase (PTP) in the regulation of the activity of SK channels in the CCD from rats on a high K(+) diet. Western blot analysis indicated that PTP-1D is expressed in the renal cortex. Application of 1 microm phenylarsine oxide (PAO) or 1 mm benzylphosphonic acid, agents that inhibit PTP, reversibly reduced channel activity by 95%. Pretreatment of CCDs with PAO for 30 min decreased the mean NP(o) reversibly from control value 3.20 to 0.40. Addition of 1 microm herbimycin A, an inhibitor of PTK, had no significant effect on channel activity in the CCDs from rats on a high K(+) diet. However, herbimycin A abolished the inhibitory effect of PAO, indicating that the effect of PAO is the result of interaction between PTK and PTP. Addition of brefeldin A, an agent that blocks protein trafficking from Golgi complex to the membrane, had no effect on channel activity. Moreover, application of colchicine, a microtubule inhibitor, or paclitaxel, a microtubule stabilizer, had no effect on channel activity. In contrast, PAO still reduced channel activity in the presence of brefeldin A, colchicine, or paclitaxel. Furthermore, the effect of PAO on channel activity was absent when the tubules were bathed in 16% sucrose-containing bath solution or treated with concanavalin A. We conclude that PTP is involved in the regulation of the activity of SK channels and that inhibition of PTP may facilitate the internalization of the SK channels.
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Abstract
Ca2+ channels were studied in cell-attached recordings from the basolateral membrane of the bullfrog saccular hair cells with the EPC-9 patch-clamp system. Pipettes contained 110 mM Ba2+ and the membrane potential was zeroed with isotonic potassium aspartate. Data acquisition and analysis were performed using E9SCREEN and M2LAB software. L-type channel was distinguished by a single-channel conductance of 26 pS, activation range between -10 and +40 mV and intense activity even at a holding potential of -40 mV. The L-type channel showed characteristic bursts of brief openings (mode 1) interrupted occasionally by longer openings (mode 2). Bay K 8644 promoted the mode 2 activity and nifedipine inhibited L-type channel activity. Another type of calcium channels, 20 pS channel, was detected by -50 to +10 mV depolarizing steps from a holding potential of -40 or -80 mV. This channel was insensitive to dihydropyridines and resembled the N-type channel.
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Hu AM, Li JJ, Sun W, Yang DG, Yang ML, Du LJ, Gu R, Gao F, Li J, Chu HY, Zhang X, Gao LJ. Myelotomy reduces spinal cord edema and inhibits aquaporin-4 and aquaporin-9 expression in rats with spinal cord injury. Spinal Cord 2014; 53:98-102. [PMID: 25448191 DOI: 10.1038/sc.2014.209] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 10/15/2014] [Accepted: 10/20/2014] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Spinal cord edema contributes to the pathophysiological mechanisms underlying spinal cord injury (SCI) and is associated with functional recovery after SCI. Early myelotomy may be a promising surgical intervention for reducing SCI-induced edema. However, it remains unclear whether myelotomy can reduce SCI-induced edema. In addition, aquaporin-4 (AQP4) and aquaporin-9 (AQP9) have important roles in the regulation of water homeostasis. Here, we aimed to determine the effects of myelotomy on AQP4 and AQP9 expression and spinal cord edema in a rat model of moderate SCI. METHODS Rats were randomly assigned to three groups: the sham control group (n=22) receiving laminectomy alone; the contusion group (n=44) receiving laminectomy plus contusion; and the myelotomy group (n=44) receiving laminectomy plus contusion followed by myelotomy at 24 h. Functional recovery was estimated by the open-field and inclined plane tests. Spinal cord edema was determined by measuring the water content. The expression of AQP4 and AQP9 was determined by western blot. RESULTS Compared with the contusion group, myelotomy significantly improved the Basso, Beattie and Bresnahan scores in the open-field test and resulted in a higher mean angle value in the incline plane test. Myelotomy significantly reduced SCI-induced edema at 4 and 6 days after SCI, which was accompanied by downregulation of AQP4 and AQP9 expression. CONCLUSION Myelotomy improves locomotor function, reduces edema in rats with SCI and is associated with decreased expression of AQP4 and AQP9.
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Research Support, Non-U.S. Gov't |
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Xu K, Zhang M, Cui D, Fu Y, Qian L, Gu R, Wang M, Shen C, Yu R, Yang T. UCP2 -866G/A and Ala55Val, and UCP3 -55C/T polymorphisms in association with type 2 diabetes susceptibility: a meta-analysis study. Diabetologia 2011; 54:2315-24. [PMID: 21751002 DOI: 10.1007/s00125-011-2245-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Accepted: 06/20/2011] [Indexed: 11/24/2022]
Abstract
AIMS/HYPOTHESIS A meta-analysis was performed to assess the association between the UCP2 -866G/A, UCP2 Ala55Val and UCP3 -55C/T polymorphisms and type 2 diabetes susceptibility. METHODS A literature-based search was conducted to identify all relevant studies. The fixed or random effect pooled measure was calculated mainly at the allele level to determine heterogeneity bias among studies. Further analyses were performed that stratified for ethnicity. RESULTS We examined 17 publications. Stratified analysis for ethnicity and sensitivity analysis revealed that there was no heterogeneity between studies for these variants. Using an additive model, no significant association of the UCP2 -866G/A polymorphism with type 2 diabetes risk was observed, either in participants of Asian (OR 1.05, 95% CI 0.96, 1.16) or of European (OR 1.03, 95% CI 0.99, 1.07) descent. Neither the UCP2 Ala55Val nor the UCP3 -55C/T polymorphism showed any significant association with type 2 diabetes risk in Europeans (OR 1.04, 95% CI 0.98, 1.09 for Ala55Val; OR 1.04, 95% CI 1.00, 1.09 for -55C/T). In contrast, a statistically significant association was observed for both polymorphisms in participants of Asian descent (OR 1.23, 95% CI 1.12, 1.36 for Ala55Val; OR 1.15, 95% CI 1.03, 1.28 for -55C/T). CONCLUSIONS/INTERPRETATION Our meta-analysis suggests that the UCP2 -866G/A polymorphism is unlikely to be associated with increased type 2 diabetes risk in the populations investigated. In contrast, our results indicate that the UCP2 Ala55Val and UCP3 -55C/T polymorphisms may indeed be risk factors for susceptibility to type 2 diabetes in individuals of Asian descent, but not in individuals of European descent. This conclusion warrants confirmation by further studies.
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Meta-Analysis |
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Kirkus M, Grazulevicius J, Grigalevicius S, Gu R, Dehaen W, Jankauskas V. Hole-transporting glass-forming indolo[3,2-b]carbazole-based diepoxy monomer and polymers. Eur Polym J 2009. [DOI: 10.1016/j.eurpolymj.2008.10.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Gu R, Westervelt P, Ratner L. Role of HIV-1 envelope V3 loop cleavage in cell tropism. AIDS Res Hum Retroviruses 1993; 9:1007-15. [PMID: 8280475 DOI: 10.1089/aid.1993.9.1007] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The envelope protein is an important determinant of HIV-1 cell-specific tropism. The gp160 envelope precursor proteins from macrophage-tropic or T lymphoid cell line-tropic strains of HIV-1 were expressed in recombinant vaccinia virus-infected cell lines or primary lymphocytes or macrophages. No significant differences in the kinetics of synthesis of gp160, processing into gp120 and gp41 proteins, N-linked glycosylation, or release of gp120 into the medium were noted with the different envelope proteins. However, gp120 envelope protein shed into the medium was found to be at least partially cleaved at a site within the V3 loop. The gp120 envelope proteins from macrophage-tropic isolates exhibited lower rates of cleavage than those from lymphoid cell line-tropic strains in all cell types examined. Cell-free protease digestion studies also demonstrated relative resistance of the envelopes from macrophage-tropic compared to lymphoid cell line-tropic strains. All recombinant envelope proteins were recognized by monoclonal antibodies directed at gp41 or the C-terminal gp120 epitopes, and no differences in binding to CD4 were noted.
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Comparative Study |
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Liu J, Li X, Zhang H, Gu R, Wang Z, Gao Z, Xing L. Ubiquitin E3 ligase Itch negatively regulates osteoblast function by promoting proteasome degradation of osteogenic proteins. Bone Joint Res 2017; 6:154-161. [PMID: 28298321 PMCID: PMC5376659 DOI: 10.1302/2046-3758.63.bjr-2016-0237.r1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 01/17/2017] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES Ubiquitin E3 ligase-mediated protein degradation regulates osteoblast function. Itch, an E3 ligase, affects numerous cell functions by regulating ubiquitination and proteasomal degradation of related proteins. However, the Itch-related cellular and molecular mechanisms by which osteoblast differentiation and function are elevated during bone fracture repair are as yet unknown. METHODS We examined the expression levels of E3 ligases and NF-κB members in callus samples during bone fracture repair by quantitative polymerase chain reaction (qPCR) and the total amount of ubiquitinated proteins by Western blot analysis in wild-type (WT) mice. The expression levels of osteoblast-associated genes in fracture callus from Itch knockout (KO) mice and their WT littermates were examined by qPCR. The effect of NF-κB on Itch expression in C2C12 osteoblast cells was determined by a chromatin immunoprecipitation (ChIP) assay. RESULTS The expression levels of WW Domain Containing E3 Ubiquitin Protein Ligase 1 (Wwp1), SMAD Specific E3 Ubiquitin Protein Ligase 1 (Smurf1), SMAD Specific E3 Ubiquitin Protein Ligase 2 (Smurf2) and Itch were all significantly increased in the fracture callus of WT mice, which was associated with elevated expression of NF-κB members and total ubiquitinated proteins. Callus tissue isolated from Itch KO mice expressed higher levels of osteoblast-associated genes, including Runx2, a positive regulator of osteoblast differentiation, but osteoclast-associated genes were not increased. Both NF-κB RelA and RelB proteins were found to bind to the NF-κB binding site in the mouse Itch promoter. CONCLUSIONS Our findings indicate that Itch depletion may have a strong positive effect on osteoblast differentiation in fracture callus. Thus, ubiquitin E3 ligase Itch could be a potential target for enhancing bone fracture healing.Cite this article: J. Liu, X. Li, H. Zhang, R. Gu, Z. Wang, Z. Gao, L. Xing. Ubiquitin E3 ligase Itch negatively regulates osteoblast function by promoting proteasome degradation of osteogenic proteins. Bone Joint Res 2017;6:154-161. DOI: 10.1302/2046-3758.63.BJR-2016-0237.R1.
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Journal Article |
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Gu R, Wei Y, Jiang H, Balazy M, Wang W. Role of 20-HETE in mediating the effect of dietary K intake on the apical K channels in the mTAL. Am J Physiol Renal Physiol 2001; 280:F223-30. [PMID: 11208597 DOI: 10.1152/ajprenal.2001.280.2.f223] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have used the patch-clamp technique to study the effect of dietary K intake on the apical K channels in the medullary thick ascending limb (mTAL) of rat kidneys. The channel activity, defined by the number of channels in a patch and the open probability (NPo), of the 30- and 70-pS K channels, was 0.18 and 0.11, respectively, in the mTAL from rats on a K-deficient diet. In contrast, NPo of the 30- and 70-pS K channels increased to 0.60 and 0.80, respectively, in the tubules from animals on a high-K diet. The concentration of 20-hydroxyeicosatetraenoic acid (20-HETE) measured with gas chromatography-mass spectrometry was 0.8 pg/microg protein in the mTAL from rats on a high-K diet and increased significantly to 4.6 pg/microg protein in the tubules from rats on a K-deficient diet. Addition of N-methylsulfonyl-12,12-dibromododec-11-enamide (DDMS) or 17-octadecynoic acid (17-ODYA), agents that inhibit the formation of 20-HETE, had no significant effect on the activity of the 30-pS K channels. However, DDMS/17-ODYA significantly increased the activity of the apical 70-pS K channel from 0.11 to 0.91 in the mTAL from rats on a K-deficient diet. In contrast, inhibition of the cytochrome P-450 metabolism of arachidonic acid increased NPo from 0.64 to 0.81 in the tubules from animals on a high-K diet. Furthermore, the sensitivity of the 70-pS K channel to 20-HETE was the same between rats on a high-K diet and on a K-deficient diet. Finally, the pretreatment of the tubules with DDMS increased NPo of the 70-pS K channels in the mTAL from rats on a K-deficient diet to 0.76. We conclude that an increase in 20-HETE production is involved in reducing the activity of the apical 70-pS K channels in the mTAL from rats on a K-deficient diet.
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Paine E, Gu R, Ratner L. Structure and expression of the human T-cell leukemia virus type 1 envelope protein. Virology 1994; 199:331-8. [PMID: 8122365 DOI: 10.1006/viro.1994.1131] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The structure and expression of the HTLV-1 envelope protein was examined using T lymphoid cell lines infected with HTLV-1 and recombinant vaccinia viruses expressing the HTLV-1 envelope. Pulse-chase experiments demonstrated that the envelope precursor, gp62, had a half-life of 7-12 hr. N-glycosylation of the precursor protein was examined using tunicamycin and endoglycosidase H. These studies revealed that at least four and possibly five potential N-glycosylation sites were utilized. In addition, the envelope precursor was found to sediment on sucrose gradients as high-molecular-weight complexes, in positions consistent with the formation of dimers and smaller amounts of higher multimeric forms. Finally, the recombinant vaccinia system was used to express mutants designed to analyze the role in HTLV-1 envelope processing of the cytoplasmic tail and the membrane-spanning domain.
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Wang Y, Gao BY, Yue QY, Wei JC, Zhou WZ, Gu R. Color removal from textile industry wastewater using composite flocculants. ENVIRONMENTAL TECHNOLOGY 2007; 28:629-37. [PMID: 17624103 DOI: 10.1080/09593332808618824] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
In this study, the decolorization of textile wastewater using composite flocculants was examined. It was composed of Fe(III) flocculants and polydimethyldiallylammonium chloride (PDMDAAC). The color removal efficiency of the composite flocculants was compared with that of individual flocculants, ferric chloride (FeCl3), polyferric chloride (PFC) and PDMDAAC, respectively. The results showed that the composite flocculants were more efficient than individual ones in color removal. The color removal efficiency of the composite flocculants was found to be related to the weight percentage of PDMDAAC (Wp), basicity (B) of PFC and molecular weight (MW) of PDMDAAC. The removal rate is higher at a larger Wp and MW value and lower B value. Chemical oxygen demand (COD) removal from textile wastewater was also investigated in this study. During color removal by the composite flocculants, only up to 20% COD could be removed from the textile wastewater. FeCl3 was then used to further remove the remaining COD from the decolorized wastewater. This two-step treatment of textile wastewater could achieve a 91.6% reduction in COD and an 88.9% reduction in color.
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Yang DG, Li JJ, Gu R, Yang ML, Zhang X, Du LJ, Sun W, Gao F, Hu AM, Wu YY, He JG, Feng YT, Chu HY. Optimal time window of myelotomy in rats with acute traumatic spinal cord injury: a preliminary study. Spinal Cord 2013; 51:673-8. [PMID: 23752264 DOI: 10.1038/sc.2013.56] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 04/17/2013] [Accepted: 04/23/2013] [Indexed: 12/19/2022]
Abstract
OBJECTIVES Pathophysiological mechanisms underlying spinal cord injury (SCI) partially involve edema and formation of a hematoma. Myelotomy seems to be a promising intervention. However, the appropriate timing of myelotomy is still unknown in SCI. Here we aimed to determine the timing of microsurgical myelotomy in an animal model of SCI. METHODS The SCI model was contusion-induced with a new york university impactor. Sixty-five adult female rats were randomly divided into the following groups: laminectomy alone (the 'sham group', SG), laminectomy plus contusion (the 'contusion group', CG) or laminectomy plus contusion followed by myelotomy at 8, 24 or 48 h (8 h-MTG [myelotomy-treated group], 24 h-MTG or 48 h-MTG). Functional recovery was evaluated via the open field test and the inclined plane test every week after SCI. The percentage of spared white matter area (SWMA) and ultrastructure characteristics of the injured dorsolateral spinal cord were determined on the 42nd day after SCI. RESULTS Compared with the CG, myelotomy at 8 h-MTG or 24 h-MTG greatly improved the BASSO-BEATTIE- BRESNAHAN scores (P<0.008), whereas the 48 h-MTG showed less efficacy (P=0.023). All myelotomy groups showed higher mean angle values in an inclined plane test (P<0.005) and had greater percentages of SWMA than the CG. Rats in the 24 h-MTG showed a higher intra-axonal fraction and myelin fraction than those in 48 h-MTG (P<0.005). CONCLUSION Myelotomy up to 48 h after SCI improves recovery in rats. The potential time window of myelotomy may be between 8 and 24 h after SCI.
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Research Support, Non-U.S. Gov't |
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Abstract
BACKGROUND Chinese herbal medicines are commonly used to treat sore throat in China and among Chinese people worldwide. Their efficacy in treating sore throat has not previously been systematically reviewed. OBJECTIVES To assess the efficacy and safety of Chinese herbal medicines for patients with sore throat. SEARCH STRATEGY We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 3, 2006) which contains the Acute Respiratory Infections Group's specialised register; MEDLINE (1966 to August 2006); EMBASE (1980 to August 2006); AMED (1985 to August 2006); the Chinese Biomedical Database (CBM) (1975 to August 2006), and China National Knowledge Infrastructure (CNKI) (1994 to August 2006). SELECTION CRITERIA We only included randomised controlled trials (RCTs) assessing Chinese herbal medicines for the treatment of sore throat with the outcomes of recovery, inefficacy, and adverse events. DATA COLLECTION AND ANALYSIS One review author contacted the trial authors of claimed RCTs. Three review authors extracted and analysed the data. MAIN RESULTS Seven trials involving 1253 participants were included. All trials were identified as being of methodologically poor quality (C category). All of the Chinese herbal preparations in this review were inadequately characterised and were assessed in one trial only. It is highly likely that there was selection bias or detection bias, or both, in all of the included trials. Conflict of interest may have been another factor in producing a positive result in three studies as the prepared drugs were made in the trial author's hospital. We did not perform a meta-analysis and the results of the studies are reported separately. Three formulations were shown to be superior to the control in improving recovery: Ertong Qingyan Jiere Koufuye was more effective than Fufang Shuanghua Koufuye for acute pharyngitis (OR 1.54, 95% Cl 1.11 to 5.74); Yanhouling mixture was more effective than the gentamicin atomised inhalation for acute pharyngitis (OR 5.39, 95% CI 2.69 to 10.81) for acute pharyngitis; and Qinganlan Liyan Hanpian was more effective than Fufang Caoshanhu Hanpian for chronic pharyngitis (OR 2.25, 95% CI 1.08 to 4.67). Four four formulations were shown to be equal in efficacy to the control. AUTHORS' CONCLUSIONS Based on the existing evidence included in this review, the efficacy of Chinese herbal medicine for treating sore throat is controversial and questionable. We cannot recommend any kind of Chinese medical herbal formulation as an effective remedy for sore throat, due to the lack of high quality clinical trials.
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Zhai S, Jiang S, Gu R, Yang W, Wang P. Effects of impulse noise on cortical response threshold and inner ear activity of succinic dehydrogenase and acetylcholinesterase in guinea pigs. Acta Otolaryngol 1998; 118:813-6. [PMID: 9870625 DOI: 10.1080/00016489850182495] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The effects of impulse noise (firecrackers at 170 dB SPL, 1, 10, 20 rounds) on auditory cortical response threshold (CRT) and activity of succinic dehydrogenase (SDH) and acetylcholinesterase (AchE) in the inner ear were studied in 37 guinea pigs. The results showed that extent of damage in the cochlea was related to amount of exposure to the noise. Exposure to 10 rounds resulted in temporal threshold shift (TTS); to 20 rounds the result was permanent threshold shift (PTS). For the period when TTS existed, inverse correlation was noticed between enzyme activity change and CRT shift. The correlation could not be established when PTS was induced. The results suggest that the pathomechanism of PTS was more complex than that of TTS. The significance of the results is discussed.
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Hu X, Huang S, Gu R, Yuan C, Ge H, Chen Y. An oxygen-insensitive degradable resist for fabricating metallic patterns on highly curved surfaces by UV-nanoimprint lithography. Macromol Rapid Commun 2014; 35:1712-8. [PMID: 25186342 DOI: 10.1002/marc.201400251] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 06/30/2014] [Indexed: 11/07/2022]
Abstract
In this paper, an oxygen-insensitive degradable resist for UV-nanoimprint is designed, com-prising a polycyclic degradable acrylate monomer, 2,10-diacryloyloxymethyl-1,4,9,12-tetraoxa-spiro [4.2.4.2] tetradecane (DAMTT), and a multifunctional thiol monomer pentaerythritol tetra(3-mercaptopropionate) (PETMP). The resist can be quickly UV-cured in the air atmosphere and achieve a high monomer conversion of over 98%, which greatly reduce the adhesion force between the resist and the soft mold. High conversion, in company with an adequate Young's modulus (about 1 GPa) and an extremely low shrinkage (1.34%), promises high nanoimprint resolution of sub-50 nm. The cross-linked resist is able to break into linear molecules in a hot acid solvent. As a result, metallic patterns are fabricated on highly curved surfaces via the lift off process without the assistance of a thermoplastic polymer layer.
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Abstract
BACKGROUND Measles is an infectious disease caused by Morbillivirus. Chinese physicians believe that medicinal herbs are effective in alleviating symptoms and preventing complications. Chinese herbal medicines are dispensed according to the particular symptoms. OBJECTIVES To assess the effectiveness and possible adverse events of Chinese medicinal herbs in treating measles. SEARCH STRATEGY We searched the Cochrane Central Register of Controlled Clinical Trials (CENTRAL) (The Cochrane Library Issue 4, 2005); MEDLINE (1966 to June 2005); EMBASE (1980 to June 2005); the Chinese Biomedical Database (1976 to June 2005); VIP Information (1989 to June 2005); China National Knowledge Infrastructure (CNKI) (1994 to June 2005); and the metaRegister of Controlled Trials was searched for ongoing trials. SELECTION CRITERIA Randomised controlled trials (RCTs) in which patients with measles without complications were treated with Chinese medicinal herbs were included. DATA COLLECTION AND ANALYSIS The primary outcome measure was death from any cause. The secondary outcome measure was improvement of overall symptoms. The tertiary outcome measure was fever clearance time. MAIN RESULTS We identified 28 trials which claimed to use random allocation. Nineteen study authors were contacted by telephone and we discovered that the allocation methods they had used were not actually randomised. Three studies were excluded because the patients experienced complications. We were unable to contact the remaining six authors. These require further assessment and have been allocated to the 'Studies awaiting assessment' section. AUTHORS' CONCLUSIONS Two authors independently assessed trial quality and extracted data. We interviewed by telephone the study authors for missing information regarding random allocation of the study process. Some trials allocated the participants according to the sequence they were admitted to the trials, that is to say, by using a pseudo-random allocation method. None of the trials concealed the allocation or blinding method. We hope future randomised controlled trials (RCTs) in this field will be conducted.
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Gu R, Zhang Z, Carmichael GG. How a small DNA virus uses dsRNA but not RNAi to regulate its life cycle. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2007; 71:293-9. [PMID: 17381309 DOI: 10.1101/sqb.2006.71.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Mouse polyomavirus contains a circular DNA genome, with early and late genes transcribed from opposite strands. At early times after infection, genes encoded from the early transcription unit are predominantly expressed. After the onset of viral DNA replication, expression of genes encoded from the late transcription unit increases dramatically. At late times, late primary transcripts are inefficiently polyadenylated, leading to the generation of multigenomic RNAs that are precursors to mature mRNAs. These transcripts contain sequences complementary to the early RNAs and downregulate early-strand gene expression by inducing RNA editing. Our recent work leads to a model where the production of the multigenomic late RNAs is also controlled by the editing of poly(A) signals, directed by overlapping primary transcripts.
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MESH Headings
- Animals
- Base Sequence
- Gene Expression Regulation, Developmental
- Gene Expression Regulation, Viral
- Genome, Viral
- Mice
- Models, Biological
- Polyomavirus/genetics
- Polyomavirus/growth & development
- Polyomavirus/physiology
- RNA Interference
- RNA Splicing
- RNA, Antisense/genetics
- RNA, Antisense/metabolism
- RNA, Double-Stranded/genetics
- RNA, Double-Stranded/metabolism
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Virus Replication/genetics
- Virus Replication/physiology
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Upadhyay A, Senyschyn D, Santos L, Gu R, Carroll GJ, Jazayeri JA. K/B×N serum transfer arthritis is delayed and less severe in leukaemia inhibitory factor (LIF)-deficient mice. Clin Exp Immunol 2012; 169:71-8. [PMID: 22774981 DOI: 10.1111/j.1365-2249.2012.04601.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
This study is investigating the role of leukaemia inhibitory factor (LIF) in the development of inflammation and joint damage in the mouse K/B×N serum transfer arthritis model. LIF knock-out (LIF(-/-)) mice were generated by mating heterozygote females (LIF(+/-)) with heterozygote males. Arthritis was induced in 8-20-week-old LIF knock-out mice (LIF(-/-)) by intraperitoneal injection of pooled K/B×N sera (50 µl) on days 0 and 2. Clinical disease was scored daily for 6 days. Safranin-O and haematoxylin-stained sections were scored for synovitis, joint space exudate, cartilage degradation and bone damage. RNA was extracted from ankle joints and used to investigate gene expression levels of tumour necrosis factor (TNF)-α, interleukin (IL)-1, LIF, LIF receptor, oncostatin M (OSM), OSM receptor, IL-6 and their common receptor subunit gp130 by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The results show that wild-type mice developed severe clinically overt polyarthritis. In contrast, LIF(-/-) mice showed a more than 50% reduction in clinical arthritis severity. Significantly lower histological scores were observed in LIF(-/-) mice compared to wild-type disease controls. LIF(-/-) mice had histopathological scores that were similar to normal healthy mice. IL-6 subfamily cytokine and receptor subunit expression remained unchanged. The expression levels for IL-6 were reduced significantly in all the diseased mice, whether wild-type or LIF(-/-) mice (P < 0·001), compared to healthy wild-type mice. We conclude that LIF contributes to the development of disease in the K/B×N serum transfer model of arthritis. These results provide further evidence for the role of LIF in inflammation and cartilage bone resorption and provide impetus to test the effects of LIF blockade as a therapeutic strategy in rheumatoid arthritis.
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Gu R, McCutcheon S, Chen CJ. Development of Weather-Dependent Flow Requirements for River Temperature Control. ENVIRONMENTAL MANAGEMENT 1999; 24:529-540. [PMID: 10501865 DOI: 10.1007/s002679900252] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
/ Streamflow influences biological processes, habitat, and ecological integrity of streams in a number of vital ways. The establishment of weather-dependent minimum flows is essential to the protection of the aquatic environment and wildlife habitat from the adverse impacts of high water temperatures and to the effective utilization of the assimilative capacity of instream flows. In this study, weather-dependent flow requirements for summer river temperature control are derived from quantitative temperature-flow relationships. Correlation and regression of historical data and an analytical solution to the basic heat balance equation are employed to quantify the impacts of stream flow on river temperatures. Five-year continuous field measurements from the Platte River, Nebraska, USA, are used to illustrate the practical application in water-quality management. The methods and results demonstrate the feasibility of temperature control through streamflow management to meet water temperature standards and protect the aquatic biota by setting the appropriate weather-related minimum river discharges. The flow requirements are evaluated by a comparison with a critical discharge. Information provided in this paper will assist in planning streamflow regulation, design of river and reservoir operations, and application of water-quality criteria in environmental management.KEY WORDS: River discharges; Flow management; Habitat; Water quality; Weather; Wildlifehttp://link.springer-ny.com/link/service/journals/00267/bibs/24n4p529.html</HEA
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Jiang L, Gu R, Li X, Mu D. Simple and rapid detection Aspergillus fumigatus by loop-mediated isothermal amplification coupled with lateral flow biosensor assay. J Appl Microbiol 2021; 131:2351-2360. [PMID: 33788361 DOI: 10.1111/jam.15092] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 03/05/2021] [Accepted: 03/24/2021] [Indexed: 11/30/2022]
Abstract
AIMS We have developed a new diagnostic technique, termed loop-mediated isothermal amplification coupled with lateral flow biosensor (LAMP-LFB), which has been successfully applied to the detection of Aspergillus fumigatus. MATERIAL AND METHODS A set of six LAMP primers was designed according to the A. fumigatus-specific anxC4 gene, which specifically recognized eight different regions of the target sequence. The LFB was employed for reporting the A. fumigatus-LAMP results, and the visual readouts were obtained within 2 min. The strains of A. fumigatus species and non-A. fumigatus species were used to test the assay's sensitivity and examine the analytical specificity of the target assay. Optimal LAMP conditions were 66°C for 50 min. The limit of detection is 100 fg. No cross-reactions were obtained, and the specificity of LAMP-LFB assay was 100%. The whole process of the assay, including 20 min of DNA preparation, 50 min of constant temperature amplification, and 2 min of detection by the sensor strip, took a total of 72 min (less than 75 min). Among 89 sputum specimens for clinical evaluation, 10 (11·23%) samples were A. fumigatus-positive by LAMP-LFB and traditional culture method, 9 (10·11%) samples were A. fumigatus-positive by PCR method. Compared with culture method, the diagnostic accuracy of LAMP-LFB method was 100%. CONCLUSIONS The novel LAMP-LFB detection technology established in the current research is a rapid and reliable detection tool for A. fumigatus. SIGNIFICANCE AND IMPACT OF THE STUDY This novel LAMP-LFB assay can quickly, specifically and sensitively detect A. fumigatus, thereby speeding up the detection process and increasing the detection rate. In addition, it can also be used as a new molecular method for detection of A. fumigatus in clinical and laboratory areas.
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Fu BT, Jiang SC, Gu R, Ottaviani F, Rosignoli M, Paludetti G. 40-Hz auditory event-related potential in normal adults. AUDIOLOGY : OFFICIAL ORGAN OF THE INTERNATIONAL SOCIETY OF AUDIOLOGY 1988; 27:247-52. [PMID: 3190564 DOI: 10.3109/00206098809081595] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
40-Hz event-related potentials (AERP) in response to 0.5-, 1-, 2- and 4-kHz tone pips were studied in 45 subjects (18 males and 27 females) in order to assess their reliability and threshold in normal adults and to study the effects of stimulus frequency and intensity on their latency and amplitude. In all subjects well-formed and reproducible 40-Hz AERP were detected, thus showing a good reliability of 40-Hz AERP to tone pips. The response was always detectable within 15 dB nHL intensity level and showed a sequence of positive (P1, P2 and P3) and negative (N1, N2 and N3) waves. It has also been observed that the latency of the first component following the acoustic stimulus decreased at increasing stimulus frequency and intensity, while the amplitude of the whole response increased upon increasing stimulus intensity. It can be suggested that the 40-Hz AERP to tone pips may represent a useful tool in assessing auditory threshold in the low-frequency range.
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Corwin JT, Warchol ME, Saffer LD, Finley JE, Gu R, Lamber PR. Growth factors as potential drugs for the sensory epithelia of the ear. CIBA FOUNDATION SYMPOSIUM 2007; 196:167-82; discussion 182-7. [PMID: 8866134 DOI: 10.1002/9780470514863.ch12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The highly ordered structures of the hearing and balance organs of vertebrate ears go through a coordinated sequence of cellular and morphogenetic events. It is to be expected that protein growth factors and other extracellular signals will regulate many events during embryonic development of the ear, including the induction of the ear, the specific induction of sensory epithelia, the proliferation of the cells that form the sensory epithelia, the differentiation of the sensory and supporting cells, and the attraction and maintenance of innervation. After embryonic development, growth factors will support cell survival and innervation of new sensory cells. In damaged sensory epithelia, supplementation of the normal growth factors in these tissues has the potential to influence cellular responses to trauma, to reduce cell death and to promote the replacement of dead cells through renewed proliferation and differentiation, so as to improve hearing and balance health via preventive and restorative treatments. Assessment of the influences of specific growth factors on the sensory epithelia of vertebrate ears is at an early stage: this paper provides a brief account of what we know from studies of normal and experimentally manipulated epithelia, discusses the current questions and suggests directions for future studies.
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Wu T, Gu R, Zhang M, Liu G. Chinese medicinal herbs for measles. THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS 2005. [DOI: 10.1002/14651858.cd005531] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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