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Wen X, Fang G, Li H, Jiang Z, Du X, Liao Z, Liu R, Huang G, Meng F, Liao W, Zhang Z. CircIRAK3 exerts negative feedback regulation on inflammation by binding to HNRNP U and destabilizing proinflammatory cytokine mRNA in osteoarthritis and chondrogenesis. Int J Biol Macromol 2024; 256:128453. [PMID: 38016613 DOI: 10.1016/j.ijbiomac.2023.128453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 11/22/2023] [Accepted: 11/24/2023] [Indexed: 11/30/2023]
Abstract
Osteoarthritis (OA) is the most prevalent age-related and degenerative joint disease with limited treatment options. Previous studies have identified the therapeutic effects of mesenchymal stem cells (MSCs) therapy. Nevertheless, chronic inflammation impedes MSCs therapeutic effect. There have been reports suggesting that circular RNAs (circRNAs) are involved in OA and chondrogenesis. The combination of MSCs and circRNAs in therapies appears to be a promising option. In this study, we identified circIRAK3 as a significant regulator in cartilage degeneration and chondrogenesis through high-throughput sequencing analyses. We observed increased circIRAK3 in OA cartilage and during MSCs chondrogenesis. Knockdown of circIRAK3 resulted in excessive apoptosis, inhibited proliferation, and degradation of chondrocytes, along with the inhibition of MSCs chondrogenesis. Mechanistically, circIRAK3 bound to HNRNP U and competitively prevented its binding to IL-1β, TNFα, and IL6 mRNA, thereby promoting mRNA degradation. Notably, circIRAK3 expression in plasma increased with higher OARSI scores. Intra-articular injection of adeno-associated virus-circIRAK3 delayed cartilage degeneration and reduced inflammation in DMM mouse model. Our study highlights a compensatory regulation network of circIRAK3 in chondrocytes in response to inflammation. CircIRAK3 has the potential to serve as a new therapeutic target for OA. Furthermore, therapies targeting circIRAK3 combined with MSCs hold promise.
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Affiliation(s)
- Xingzhao Wen
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou, Guangdong 510080, China; Department of Medicine, Solna, Karolinska Institutet, Centre for Molecular Medicine, Karolinska University Hospital, Stockholm 171 64, Sweden
| | - Guibin Fang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou, Guangdong 510080, China
| | - Hongyi Li
- Department of Orthopaedics, Qingyuan People's Hospital/the Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan, China
| | - Zongrui Jiang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou, Guangdong 510080, China
| | - Xue Du
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou, Guangdong 510080, China
| | - Zhuangyao Liao
- Department of Orthopedics, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510120, China
| | - Ruonan Liu
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou, Guangdong 510080, China
| | - Guiwu Huang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou, Guangdong 510080, China
| | - Fangang Meng
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou, Guangdong 510080, China
| | - Weiming Liao
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou, Guangdong 510080, China
| | - Zhiqi Zhang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou, Guangdong 510080, China.
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Fang G, Wen X, Jiang Z, Du X, Liu R, Zhang C, Huang G, Liao W, Zhang Z. FUNDC1/PFKP-mediated mitophagy induced by KD025 ameliorates cartilage degeneration in osteoarthritis. Mol Ther 2023; 31:3594-3612. [PMID: 37838829 PMCID: PMC10727975 DOI: 10.1016/j.ymthe.2023.10.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/12/2023] [Accepted: 10/11/2023] [Indexed: 10/16/2023] Open
Abstract
Osteoarthritis (OA) is the most common joint disease, but no disease-modifying drugs have been approved for OA treatment. Mitophagy participates in mitochondrial homeostasis regulation by selectively clearing dysfunctional mitochondria, which might contribute to cartilage degeneration in OA. Here, we provide evidence of impaired mitophagy in OA chondrocytes, which exacerbates chondrocyte degeneration. Among the several classic mitophagy-regulating pathways and receptors, we found that FUNDC1 plays a key role in preserving chondrocyte homeostasis by inducing mitophagy. FUNDC1 knockdown in vitro and knockout in vivo decreased mitophagy and exacerbated mitochondrial dysfunction, exacerbating chondrocyte degeneration and OA progression. FUNDC1 overexpression via intra-articular injection of adeno-associated virus alleviated cartilage degeneration in OA. Mechanistically, our study demonstrated that PFKP interacts with and dephosphorylates FUNDC1 to induce mitophagy in chondrocytes. Further analysis identified KD025 as a candidate drug for restoring chondrocyte mitophagy by increasing the FUNDC1-PFKP interaction and thus alleviating cartilage degeneration in mice with DMM-induced OA. Our study highlights the role of the FUNDC1-PFKP interaction in chondrocyte homeostasis via mitophagy induction and identifies KD025 as a promising agent for treating OA by increasing chondrocyte mitophagy.
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Affiliation(s)
- Guibin Fang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou 510080, Guangdong, China; Department of Orthopedics, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou 510080, China
| | - Xingzhao Wen
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou 510080, Guangdong, China; Department of Medicine, Solna, Karolinska Institutet, and Centre for Molecular Medicine, Karolinska University Hospital, 171 64 Stockholm, Sweden
| | - Zongrui Jiang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou 510080, Guangdong, China
| | - Xue Du
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou 510080, Guangdong, China
| | - Ruonan Liu
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou 510080, Guangdong, China
| | - Chengyun Zhang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou 510080, Guangdong, China
| | - Guiwu Huang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou 510080, Guangdong, China
| | - Weiming Liao
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou 510080, Guangdong, China
| | - Zhiqi Zhang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China; Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Guangzhou 510080, Guangdong, China.
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Saenz FR, Dabaja B, Fang G, Daver N, Kantarjian HM, Spiotto MT. Irradiated Extramedullary Acute Myeloid Leukemia Increases Survival in a Leukemic Mouse Model. Int J Radiat Oncol Biol Phys 2023; 117:S161. [PMID: 37784404 DOI: 10.1016/j.ijrobp.2023.06.255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) The systemic nature of AML likely limits their immunogenicity because antigen presentation is primarily mediated by splenic dendritic cells, which induces immune tolerance. Since antigen presentation in tissue draining lymph nodes can induce anti-tumor immune responses, we hypothesized that local irradiation of cutaneous, extramedullary leukemias will increase immunogenic cell death, dendritic cell maturation and improved survival. MATERIALS/METHODS A murine AML cell line C1498 was assessed for immunogenic markers calreticulin (CALR), HMGB1 and cGAS-STING pathway using fluorescence cytometry and qRT-PCR. Syngeneic mice were injected with C1498 subcutaneously to model extramedullary lesions and intravenously to model systemic leukemias. Cells and subcutaneous tumor were focally irradiated with 2 Gy or 8 Gy. Two-way ANOVA and Student's t-test were used for paired-wise comparisons. Survival was estimated by Kaplan-Meier plot and groups were compared using log-rank test. RESULTS C1498 cells or tumors irradiated with 2 Gy or 8 Gy showed increased CALR and HMGB1 as well as (cGAS/Md21b1; 5-fold; p<0.001) and interferon alpha (Ifna; 3-fold; p<0.001) after 48h (18- and 4-fold, respectively; p<0.05) compared to not treated controls (NTC). Irradiated C1498 subcutaneous tumors displayed increased CD11b-positive cells (9-fold; p<0.001), CD11c (6-fold; p<0.001), and MHCII-positive CD11c cells (4-fold; p<0.01) in irradiated tumors compared to NTC. Irradiation of subcutaneous C1498 tumors increased median survival in mice also injected with C1498 cells intravenously compared to non-irradiated mice bearing systemic leukemias (46 vs. 25 days; p<0.01). Irradiation of C1498 tumors combined with anti-PDL1 treatment further increased median survival in our leukemia model compared to untreated controls (>50 vs. <30 days; p<0.001). CONCLUSION Irradiated extramedullary AML increased immunogenic markers and activation of immune effector cells that correlated with increased survival in mice also bearing systemic leukemia. These results suggest focal irradiation of extramedullary AML may facilitate eradiation of systemic leukemias.
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Affiliation(s)
- F R Saenz
- Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - B Dabaja
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - G Fang
- Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - N Daver
- The University of Texas MD Anderson Cancer Center, Houston, TX
| | - H M Kantarjian
- The University of Texas MD Anderson Cancer Center, Houston, TX
| | - M T Spiotto
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
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France G, Volianskis R, Ingram R, Bannister N, Rothärmel R, Irvine MW, Fang G, Burnell ES, Sapkota K, Costa BM, Chopra DA, Dravid SM, Michael-Titus AT, Monaghan DT, Georgiou J, Bortolotto ZA, Jane DE, Collingridge GL, Volianskis A. Differential regulation of STP, LTP and LTD by structurally diverse NMDA receptor subunit-specific positive allosteric modulators. Neuropharmacology 2022; 202:108840. [PMID: 34678377 PMCID: PMC8803579 DOI: 10.1016/j.neuropharm.2021.108840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 10/05/2021] [Accepted: 10/13/2021] [Indexed: 11/30/2022]
Abstract
Different types of memory are thought to rely on different types of synaptic plasticity, many of which depend on the activation of the N-Methyl-D Aspartate (NMDA) subtype of glutamate receptors. Accordingly, there is considerable interest in the possibility of using positive allosteric modulators (PAMs) of NMDA receptors (NMDARs) as cognitive enhancers. Here we firstly review the evidence that NMDA receptor-dependent forms of synaptic plasticity: short-term potentiation (STP), long-term potentiation (LTP) and long-term depression (LTD) can be pharmacologically differentiated by using NMDAR ligands. These observations suggest that PAMs of NMDAR function, depending on their subtype selectivity, might differentially regulate STP, LTP and LTD. To test this hypothesis, we secondly performed experiments in rodent hippocampal slices with UBP714 (a GluN2A/2B preferring PAM), CIQ (a GluN2C/D selective PAM) and UBP709 (a pan-PAM that potentiates all GluN2 subunits). We report here, for the first time, that: (i) UBP714 potentiates sub-maximal LTP and reduces LTD; (ii) CIQ potentiates STP without affecting LTP; (iii) UBP709 enhances LTD and decreases LTP. We conclude that PAMs can differentially regulate distinct forms of NMDAR-dependent synaptic plasticity due to their subtype selectivity. This article is part of the Neuropharmacology Special Issue on ‘Glutamate Receptors – NMDA receptors’. NMDAR-dependent STP, LTP and LTD can be dissociated pharmacologically GluN2A/2B PAM UBP714 potentiates LTP and reduces LTD GluN2C/D PAM CIQ potentiates STP without affecting LTP NMDAR pan-PAM UBP709 potentiates LTD and reduces LTP
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Affiliation(s)
- G France
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - R Volianskis
- Department of Physiology, University of Toronto, Toronto, ON, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, ON, Canada
| | - R Ingram
- Centre for Neuroscience, Surgery and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK
| | - N Bannister
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - R Rothärmel
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - M W Irvine
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - G Fang
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - E S Burnell
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK; University of Exeter, St Luke's Campus, Heavitree Road, Exeter, UK
| | - K Sapkota
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - B M Costa
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, USA & Center for One Health Research, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - D A Chopra
- Department of Pharmacology and Neuroscience, Creighton University School of Medicine, Omaha, Nebraska, USA
| | - S M Dravid
- Department of Pharmacology and Neuroscience, Creighton University School of Medicine, Omaha, Nebraska, USA
| | - A T Michael-Titus
- Centre for Neuroscience, Surgery and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK
| | - D T Monaghan
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - J Georgiou
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, ON, Canada
| | - Z A Bortolotto
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - D E Jane
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - G L Collingridge
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK; Department of Physiology, University of Toronto, Toronto, ON, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, ON, Canada; TANZ Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - A Volianskis
- Schools of Clinical Sciences and Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK; Centre for Neuroscience, Surgery and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK; School of Biosciences, Museum Avenue, Cardiff University, Cardiff, CF10 3AX, UK.
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Ma S, Xian M, Yang B, Fang G, Lou H, Yu W, Wang X, Xian J, Song X, Fan E, Li Y, Zhang L, Wang C. Pathological changes from the originating to the peripheral sites of Sinonasal Inverted Papilloma are the underlying mechanisms of preoperative MRI-tumor origin prediction. Rhinology 2020; 58:59-65. [PMID: 31448805 DOI: 10.4193/rhin19.131] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Our previous study showed that convoluted cerebriform pattern (CCP)-based reverse tracing method in preoperative magnetic resonance imaging (MRI) is a reliable tool in predicting originating site of sinonasal inverted papilloma (SNIP). This study aimed to determine the underlying pathological mechanism of the preoperative MRI-CCP reverse tracing method by assessing the histopathological changes from the origin to the peripheral sites of SNIP. METHODOLOGY The originating site of SNIP was predicted by preoperative MRI in 30 consecutive patients suspected to have primary SNIP. Samples of SNIP originating and peripheral sites were processed by pathological staining for evaluation of stroma score, micro-vessel density (MVD), and tight junction proteins (claudin-5, zonula occludens (ZO)-1 and occludin) expression. RESULTS The originating site of SNIP was accurately predicted by preoperative MRI in all patients. Stroma scores, and MVD were significantly greater in the periphery of SNIP than in the originating site. In contrast, Claudin-5 expression in micro-vessels was greater at the originating site than the periphery. CONCLUSIONS More edematous stroma and intensive micro-vessels with defective tight junction in periphery of SNIP result in more contrast agent diffusing and CCP that can only be observed at the periphery of SNIP on T2 and contrast-enhanced T1 weighted MR images, which may be the mechanisms underlying the CCP reverse tracing method.
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Affiliation(s)
- S Ma
- Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - M Xian
- Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - B Yang
- Department of Radiology, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - G Fang
- Department of Otolaryngology Head and Neck Surgery, Beijing DiTan Hospital, Capital Medical University, Beijing, PR China
| | - H Lou
- Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - W Yu
- Department of Radiology, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - X Wang
- Beijing Key Laboratory of nasal diseases, Beijing Institute of Otolaryngology, Beijing, PR China; Department of Allergy, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - J Xian
- Department of Radiology, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - X Song
- Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - E Fan
- Beijing Key Laboratory of nasal diseases, Beijing Institute of Otolaryngology, Beijing, PR China
| | - Y Li
- Beijing Key Laboratory of nasal diseases, Beijing Institute of Otolaryngology, Beijing, PR China
| | - L Zhang
- Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China; Department of Radiology, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China; Department of Allergy, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - C Wang
- Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
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Zhang L, Fang G, Yu W, Yang B, Wang C, Zhang L. Prediction of malignant sinonasal inverted papilloma transformation by preoperative computed tomography and magnetic resonance imaging. Rhinology 2020; 58:248-256. [PMID: 32441707 DOI: 10.4193/rhin19.240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Accurate preoperative prediction of the malignant transformation of sinonasal inverted papilloma (SNIP) is essential for radical resection of tumours and prevention of recurrence. We here explored the predictive value of preoperative computed tomography (CT) and magnetic resonance imaging (MRI). METHODOLOGY The study was performed on 268 patients with SNIP with (n = 78) or without (n = 190) coexistent malignant transformation. We used univariate and multivariate logistic regression analysis method to screen for independent risk factors, and established a nomogram model. Finally, using receiver operating characteristic curves, we assessed the diagnostic value of the independent risk factors for malignant transformation of SNIP. RESULTS We identified bone erosion on CT, change in convoluted cerebriform pattern (CCP) on MRI, and washout-type time intensity curve (TIC) of dynamic contrast-enhanced (DCE)-MRI were independent predictors of malignant transformation of SNIP. The scores of these three independent risk factors from the nomogram model were 10, 7 and 8, respectively. The area under the receiver operating characteristic curve for predicting SNIP malignancy was 0.954 for the nomogram model, 0.826 for bone erosion, 0.776 for washout-type TIC, and 0.810 for CCP mutation. CONCLUSIONS Of the independent risk factors and related combination identified, the nomogram model based on bone destruction on CT, CCP mutation on MRI, and washout-type TIC of DCE-MRI had the best predictive value for malignant transformation of SNIP.
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Affiliation(s)
- L Zhang
- Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China; Beijing Key Laboratory of nasal diseases, Beijing Institute of Otolaryngology, Beijing, PR China; Department of Otolaryngology Head and Neck Surgery, Beijing DiTan Hospital, Capital Medical University, Beijing, PR China
| | - G Fang
- Department of Otolaryngology Head and Neck Surgery, Beijing DiTan Hospital, Capital Medical University, Beijing, PR China
| | - W Yu
- Department of Radiology, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - B Yang
- Department of Radiology, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - C Wang
- Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China
| | - L Zhang
- Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China; Beijing Key Laboratory of nasal diseases, Beijing Institute of Otolaryngology, Beijing, PR China
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Qiu J, Peng P, Xin M, Wen Z, Chen Z, Lin S, Kuang M, Fu Y, Fang G, Li S, Li C, Mao J, Qin L, Ding Y. ZBTB20-mediated titanium particle-induced peri-implant osteolysis by promoting macrophage inflammatory responses. Biomater Sci 2020; 8:3147-3163. [PMID: 32363359 DOI: 10.1039/d0bm00147c] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Aseptic loosening (AL) caused by wear particles released from implant surfaces is one of the main causes for the failure of artificial joints, which is initiated by macrophage inflammatory responses. Emerging evidence suggests that the member of a broad-complex, tramtrack, bric-a-brac/poxvirus and zinc finger (BTB/POZ) family as well as zinc finger and BTB domain-containing protein 20 (ZBTB20) can inhibit IκBα gene transcription, promote NF-κB activation, and initiate innate immune responses. The molecular mechanism(s) by which ZBTB20 contributes to titanium particle (TiP)-induced macrophage inflammatory responses and osteolysis has not been fully elucidated. Here, we showed that ZBTB20 increased either in the AL group's synovial membranes or in TiP-stimulated bone-marrow-derived macrophages (BMDMs) as compared to that in the control groups. Moreover, the knockdown of ZBTB20 led to the inhibition of proinflammatory factors induced by TiPs in BMDMs, such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interferon-β (IFN-β). Here, we also reported that the knockdown of ZBTB20 suppressed TiP-induced NF-κB activation and M1 polarization as well as stabilized the trans Golgi network (TGN) in BMDMs. The dual-luciferase reporter assay identified the binding between the IκBα promoter and ZBTB20, and IκBα knockdown could rescue the antiinflammatory effects induced by the ZBTB20 knockdown in BMDMs. Finally, we found that sh-ZBTB20 lentivirus injection could reduce TiP-induced osteolysis in mouse calvaria, inhibiting TiP-induced proinflammatory factors and loss of bone volume/total volume (BV/TV) as well as bone mineral density (BMD). These results suggest that ZBTB20 positively regulated NF-κB activation and M1 polarization as well as the production of TGN-derived tubular carriers in BMDMs, playing a positive role in macrophage activation and mouse cranial osteolysis induced by TiPs. It may be a potential therapeutic target for the prevention of aseptic loosening of prostheses.
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Affiliation(s)
- Junxiong Qiu
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China.
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Fang G, Fu Y, Li S, Qiu J, Kuang M, Lin S, Li C, Ding Y. The USP14-NLRC5 pathway inhibits titanium particle-induced osteolysis in mice by suppressing NF-κB and PI3K/AKT activities. J Biol Chem 2020; 295:7018-7032. [PMID: 32273344 DOI: 10.1074/jbc.ra119.012495] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 03/31/2020] [Indexed: 12/21/2022] Open
Abstract
Total hip arthroplasty (THA) is a widely-used surgical intervention for treating patients with end-stage degenerative and inflammatory osteoarthropathy. However, wear particles from the artificial titanium joint can induce osteolysis, limiting the long-term survivorship of THA. Monocyte/macrophage lineage cells are the key players in the response to wear particles, and the proinflammatory NF-κB and phosphoinositide 3-kinase (PI3K)-AKT Ser/Thr kinase (AKT)-signaling pathways have been shown to be the most important contributors to wear particle-induced osteolysis. In contrast, ubiquitin-specific protease 14 (USP14) specifically removes the polyubiquitin chains from the nucleotide-binding and oligomerization domain (NOD)-like receptor family Caspase recruitment domain (CARD)-containing 5 (NLRC5) and thereby enhances the NLRC5-mediated inhibition of NF-κB signaling. In this study, we aimed to clarify the role of the USP14-NLRC5 pathway in wear particle-induced osteolysis in vitro and in vivo We found that NLRC5 or USP14 overexpression inhibits titanium particle-induced proinflammatory tumor necrosis factor α (TNFα) production and NF-κB pathway activation, and it also decreases M1 macrophage polarization and PI3K/AKT pathway activation. Of note, NLRC5 and USP14 overexpression attenuated titanium particle-induced cranial osteolysis in mice. In conclusion, the findings of our study indicate that the USP14-NLRC5 pathway inhibits titanium particle-induced osteolysis by suppressing the NF-κB and PI3K/AKT pathways both in vitro and in vivo.
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Affiliation(s)
- Guibin Fang
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Yuan Fu
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Shixun Li
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Junxiong Qiu
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Manyuan Kuang
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Sipeng Lin
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Changchuan Li
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Yue Ding
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
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Li C, Ouyang N, Wang X, Liang A, Mo Y, Li S, Qiu J, Fang G, Fu Y, Song B, Chen Z, Ding Y. Association between the ABO blood group and primary knee osteoarthritis: A case-control study. J Orthop Translat 2019; 21:129-135. [PMID: 32309138 PMCID: PMC7152790 DOI: 10.1016/j.jot.2019.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 08/03/2019] [Accepted: 08/07/2019] [Indexed: 02/07/2023] Open
Abstract
Background Recent studies have suggested association between the ABO blood group and inflammation, which was a crucial pathological process of primary knee osteoarthritis. The aim of this study was to investigate the association between the ABO blood group and primary knee osteoarthritis and the severity of primary knee osteoarthritis evaluated by the Kellgren/Lawrence score, as well as the histopathologic association in a subgroup of patients. Methods We performed a retrospective review of patients with primary knee osteoarthritis that served as the case group and a random sampling of healthy blood donors that served as the control group. The severity of knee osteoarthritis at the first outpatient visit was evaluated by the Kellgren/Lawrence scoring system. Further study was performed to investigate the expression of blood group antigens in synovial tissue of the knee in both cases and controls. Results A total of 1126 cases and 30299 controls were involved. The proportion of AB blood group was higher in the case group than in the control group (9.7% vs. 7.8%), and logistic regression revealed that the AB blood group was a risk factor of primary knee osteoarthritis (P = 0.025 and 0.048 for univariate and multivariate analysis, respectively), independent of age (P = 0.973) and sex (P = 0.520). Patients of the blood group AB had a higher Kellgren/Lawrence score (P = 0.017). The immunohistochemical study indicated association between LeY antigen and primary knee osteoarthritis (P = 0.029). Conclusions This study suggested that the blood group AB was associated with primary knee osteoarthritis, as well as its radiological severity. Further study indicated that LeY antigen, which was related to the blood group, was associated with primary knee osteoarthritis. Translational potential of this article This study revealed that blood group AB and LeY antigen was associated with primary knee osteoarthritis, which shed new light on the nature of osteoarthritis, and the development of novel therapy for osteoarthritis.
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Key Words
- ACR, American College of Rheumatology
- ANOVA, analysis of variance
- Blood group
- CI, confidence interval
- FUT, fucosyltransferase
- HR, hazard ratio
- IHC, immunohistochemistry
- IRB, institutional review board
- K/L, Kellgren/Lawrence
- Kellgren/Lawrence
- Knee
- LeY antigen
- OA, osteoarthritis
- Osteoarthritis
- ST, synovial tissue
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Affiliation(s)
- Changchuan Li
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, China
| | - Nengtai Ouyang
- Department of Pathology, Sun Yat-sen Memorial Hospital, China
| | - Xiuju Wang
- Department of Blood Transfusion, Sun Yat-sen Memorial Hospital, China
| | - Anjing Liang
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, China
| | - Yingqian Mo
- Department of Rheumatology and Immunology, Sun Yat-sen Memorial Hospital, China
| | - Shixun Li
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, China
| | - Junxiong Qiu
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, China
| | - Guibin Fang
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, China
| | - Yuan Fu
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, China
| | - Bin Song
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, China
| | - Zhong Chen
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, China
| | - Yue Ding
- Department of Orthopaedic Surgery, Sun Yat-sen Memorial Hospital, China
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Li S, Qiu J, Qin L, Peng P, Li C, Mao J, Fang G, Chen Z, Lin S, Fu Y, Cai W, Ding Y. NOD2 negatively regulated titanium particle-induced osteolysis in mice. Biomater Sci 2019; 7:2702-2715. [PMID: 31065630 DOI: 10.1039/c9bm00306a] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
For patients undergoing total joint replacement (TJR), one of the complications, aseptic loosening, could cause serious consequences, such as revision surgery. In early research, pattern recognition receptors (PRRs) were reported to play vital roles in recognizing wear particles from the prosthesis and initiating an inflammation response. In this research, we aimed to clarify the role of nucleotide-binding and oligomerization domain containing protein 2 (NOD2), one of the PRRs, in macrophage-induced aseptic loosening in vivo and in vitro. High expressions of NOD2 and TNFα were observed from twenty patients who underwent primary or revision total hip replacements (THR). The effect of NOD2 on the activation of inflammation pathways was observed in RAW264.7 cells and CRISPR-Cas9 NOD2-knockout mice. The expressions of NOD2, the NF-κB pathway, the MAPK pathway and proinflammatory cytokine TNF-α in macrophages stimulated by wear particles were up-regulated. Otherwise, inhibition of NOD2 further up-regulated the expressions of NOD2, the NF-κB pathway, the MAPK pathway and TNF-α. Knockdown of the NOD2 gene enhanced the cranial osteolysis induced by titanium particles in a mouse model. In conclusion, our study demonstrated that NOD2 plays a negative role in osteolysis induced by titanium particles in vitro and in vivo.
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Affiliation(s)
- Shixun Li
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
| | - Junxiong Qiu
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
| | - Ling Qin
- Musculoskeletal Research Laboratory Department of Orthopaedics & Taumatology and Innovative Orthopaedic Biomaterial and Drug Translational Research Laboratory of Li Ka Shing Institute of Health Sciences, the Chinese University of Hong Kong, SAR, PR China
| | - Peng Peng
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
| | - Changchuan Li
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
| | - Jiaji Mao
- Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Guibin Fang
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
| | - Zhong Chen
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
| | - Sipeng Lin
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
| | - Yuan Fu
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
| | - Weibin Cai
- Guangdong Engineering & Technology Research Center for Disease-Model Animals, Laboratory Animal Center and Department of Biochemistry, Zhongshan Medical School, Sun Yat-Sen University, Guangzhou 510080, China.
| | - Yue Ding
- Department of Orthopaedic Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.
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Huang T, Zheng X, Fang G, Pan Y, Wang W, Wu M. A novel electrolyte additive for improving the interfacial stability of LiMn2O4 cathode lithium-ion batteries at elevated temperature. RSC Adv 2018; 8:38831-38835. [PMID: 35558326 PMCID: PMC9090668 DOI: 10.1039/c8ra08355j] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 11/05/2018] [Indexed: 11/21/2022] Open
Abstract
Methanesulfonic acid 2,2,3,3-tetrafluoropropyl (TFPMS) is newly explored as a protection additive to improve the interfacial stability of LiMn2O4 cathode/electrolyte at an elevated temperature.
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Affiliation(s)
- T. Huang
- Key Laboratory of Optoelectronic Materials Chemistry and Physics
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P. R. China
| | - X. Zheng
- Key Laboratory of Optoelectronic Materials Chemistry and Physics
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P. R. China
| | - G. Fang
- Key Laboratory of Optoelectronic Materials Chemistry and Physics
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P. R. China
| | - Y. Pan
- Key Laboratory of Optoelectronic Materials Chemistry and Physics
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P. R. China
| | - W. Wang
- Key Laboratory of Optoelectronic Materials Chemistry and Physics
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P. R. China
| | - M. Wu
- Key Laboratory of Optoelectronic Materials Chemistry and Physics
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P. R. China
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12
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Yan E, Fang G. THE FACE OF ELDER ABUSE IN ASIA. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- E. Yan
- The University of Hong Kong, Hong Kong, Hong Kong
| | - G. Fang
- The University of Hong Kong, Hong Kong, Hong Kong
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13
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Yan E, Fang G. ABUSE OF OLDER CHINESE BY FAMILY CAREGIVERS. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.1769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- E. Yan
- The Hong Kong Polytechnic University, Hong Kong, Hong Kong,
| | - G. Fang
- The University of Hong Kong, Hong Kong, Hong Kong
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14
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Fang G, Wan L, Mei W, Yu HH, Luo AL. The minimum effective concentration (MEC90) of ropivacaine for ultrasound-guided supraclavicular brachial plexus block. Anaesthesia 2016; 71:700-5. [PMID: 26945818 DOI: 10.1111/anae.13445] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2016] [Indexed: 12/31/2022]
Affiliation(s)
- G. Fang
- Department of Anesthesiology; Tongji Hospital; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
| | - L. Wan
- Department of Anesthesiology; Tongji Hospital; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
| | - W. Mei
- Department of Anesthesiology; Tongji Hospital; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
| | - H. H. Yu
- Department of Anesthesiology; Tongji Hospital; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
| | - A. L. Luo
- Department of Anesthesiology; Tongji Hospital; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
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15
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Qu Z, Fang G, Cui Z, Liu Y. Cell therapy for bone nonunion: a retrospective study. Minerva Med 2015; 106:315-321. [PMID: 26605555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
AIM The aim of this study was to report our experience in augmenting nonunion both with bone marrow mononuclear cells/mesenchymal stem cells (MSCs) and conventional surgical approaches; and for clinical applications, a simple, safe, and reproducible method to effectively treat bone mass loss disease. METHODS A retrospective analysis was performed on stem cell-treated bone nonunion patients from October 1, 2007 to October 1, 2009. Nine patients were categorized into two groups: group 1 consists of 3 patients who received autologous bone marrow mononuclear cells transplantation; group 2 consists of 6 patients who received umbilical cord MSCs (hUC-MSCs) transplantation. All patients accepted conventional surgical treatment and X-ray supervised at 3, 6, and 12 months or so after transplantation, while T cells' subtype was analyzed. RESULTS All patients were followed up for 36 months through recheck Out-patient Department and X-ray examination to observe the fracture healing. The mean time for clinical healing was comparable in both groups. The mean time of fracture lines blurred partly, continuous bone callus formation, marrow flow was 3.5M, 6.2M, and 9.1M, respectively, in the human umbilical cord mesenchymal stem cells (hUC-MSCs) treatment group. The compared healing times were 3.8 M, 7.1M and 10.6 months in autologous bone marrow mononuclear cells transplantation, respectively. The serum levels of CD4, CD56, and HLA-DR in hUC-MSCs graft group were negative, while the serum level of CD8 was 7.8% positive. Clearly, there was no significant difference in the percent of T subsets between the 2 groups of T cells' subtype. CONCLUSION Our study showed that patients treated by allograft-augmentation had no complications, reduced treatment- dissatisfaction. The use of hUC-MSCs should be offered to suitable patients in the preoperative consultation as a valuable alternative for autologous grafting and larger clinical trials should be considered in the future.
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Affiliation(s)
- Z Qu
- Department of Orthopedic Surgery, Siping Hospital of China Medical University, Siping, Jilin, China -
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16
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Guo X, Fang G, Li G, Ma H, Fan H, Yu L, Ma C, Wu X, Deng D, Wei M, Tan D, Si R, Zhang S, Li J, Sun L, Tang Z, Pan X, Bao X. Direct, Nonoxidative Conversion of Methane to Ethylene, Aromatics, and Hydrogen. Science 2014; 344:616-9. [DOI: 10.1126/science.1253150] [Citation(s) in RCA: 905] [Impact Index Per Article: 90.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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17
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Li H, Liang B, Fang G, Gang, Mu F, Xu K, Lizhi N. P0073 Image-guided percutaneous argon–helium cryoablation for painful bone tumours. Eur J Cancer 2014. [DOI: 10.1016/j.ejca.2014.03.117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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18
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Guo Y, Liao Y, Fang G, Dong J, Li Z. Increased nucleobindin-2 (NUCB2) transcriptional activity links the regulation of insulin sensitivity in Type 2 diabetes mellitus. J Endocrinol Invest 2013; 36:883-8. [PMID: 23765387 DOI: 10.3275/9000] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The protein nucleobindin-2 (NUCB2) has been recently identified as a novel satiety regulator. However, its pathophysiological role in humans remains unknown. The aims of the present study are to explore whether plasma NUCB2-1 and NUCB2 transcription activity are increased in newly diagnosed Type 2 diabetes mellitus (nT2DM) and, if so, whether changing NUCB2-1 level is a physiologic response or a compensatory mechanism for impaired insulin action. The nT2DM, impaired glucose tolerance (IGT), and healthy people (NGT, normal glucose tolerance) groups were enrolled in this study. The peripheral and hepatic insulin actions in rats with intracerebroventricular (ICV) NUCB2-1 administration were examined by euglycemic-hyperinsulinemic clamps. Plasma NUCB2-1 levels were elevated in subjects with both nT2DM and IGT compared with normal controls. NUCB2 mRNA and protein contents of muscle and adipose tissues in T2DM patients were also significantly increased compared to controls. ICV NUCB2-1 infusion in rats inhibited hepatic phosphoenolpyruvate carboxykinase (PEPCK) activity, and this was sufficient to induce insulin sensitivity in the liver and peripheral tissues during euglycemic-hyperinsulinemic clamps. In T2DM patients, there were increases in plasma NUCB2-1 levels and increases in NUCB2 mRNA and protein contents in muscle and adipose tissues. These increases are presumably a compensatory response to defective insulin action.
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Affiliation(s)
- Y Guo
- Department of Endocrinology, Yongchuan Hospital, Chongqing Medical University, 402160 Chongqing, China
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19
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Song D, Fang G, Mao SZ, Ye X, Liu G, Gong Y, Liu SF. Chronic intermittent hypoxia induces atherosclerosis by NF-κB-dependent mechanisms. Biochim Biophys Acta Mol Basis Dis 2012; 1822:1650-9. [PMID: 22846605 DOI: 10.1016/j.bbadis.2012.07.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 07/16/2012] [Accepted: 07/23/2012] [Indexed: 02/06/2023]
Abstract
Chronic intermittent hypoxia (CIH) causes atherosclerosis in mice fed a high cholesterol diet (HCD). The mechanisms by which CIH promotes atherosclerosis are incompletely understood. This study defined the mechanistic role of NF-κB pathway in CIH+HCD induced atherosclerosis. Wild type (WT) and mice deficient in the p50 subunit of NF-κB (p50-KO) were fed normal chow diet (ND) or HCD, and exposed to sham or CIH. Atherosclerotic lesions on the en face aortic preparation and cross-sections of aortic root were examined. In WT mice, neither CIH nor HCD exposure alone caused, but CIH+HCD caused evident atherosclerotic lesions on both preparations after 20weeks of exposure. WT mice on ND and exposed to CIH for 35.6weeks did not develop atherosclerotic lesions. P50 gene deletion diminished CIH+HCD induced NF-κB activation and abolished CIH+HCD induced atherosclerosis. P50 gene deletion inhibited vascular wall inflammation, reduced hepatic TNF-α level, attenuated the elevation in serum cholesterol level and diminished macrophage foam cell formation induced by CIH+HCD exposure. These results demonstrate that inhibition of NF-κB activation abrogates the activation of three major atherogenic mechanisms associated with an abolition of CIH+HCD induced atherosclerosis. NF-κB may be a central common pathway through which CIH+HCD exposure activates multiple atherogenic mechanisms, leading to atherosclerosis.
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Affiliation(s)
- D Song
- Centers for Heart and Lung Research and Pulmonary, Critical Care and Sleep Medicine, the Feinstein Institute for Medical Research, Manhasset, NY, USA
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Maurer T, Garrenton L, Oh A, Pitts K, Skelton N, Fauber B, Pan B, Malek S, Stokoe D, Bowman K, Wu J, Giannetti A, Starovasnik M, Mellman I, Jackson P, Rudolph J, Wang W, Fang G. Abstract IA24: Drugging the undruggable: Small-molecule inhibition of Ras oncoprotein. Cancer Res 2011. [DOI: 10.1158/1538-7445.fbcr11-ia24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Ras is a nucleotide-dependent switch that converts from an inactive GDP-bound state to an active GTP-bound state when activated by guanine nucleotide exchange factors, such as SOS. Active RasGTP then binds to and activates downstream signaling effectors. Ras is the most frequently mutated oncogene and hyperactive mutant Ras constitutively signals to effectors to promote cell survival, proliferation and metastasis. Thus, Ras oncoprotein has been considered by the cancer community to be one of the most important oncology drug targets. Despite the enormous interest and extensive exploratory efforts in industry and academia, small molecules that bind to Ras in a well-defined manner and exert inhibitory effects have not been uncovered to date. We report here the identification and characterization of small-molecule inhibitors of the Ras oncoprotein.
To explore a new means of directly targeting Ras, we used a fragment-based lead discovery approach via an NMR-based screen. Hits from the fragment screen were characterized for their interactions with Ras by NMR and X-ray crystallography and for their effects on Ras activation and signaling in reconstituted biochemical assays in vitro and in cellular assays in vivo. From the fragment-based screen, we identified a group of small molecules that each bind to a common site adjacent to the switch I/II regions in the Ras protein. X-ray crystallography studies of three compound-Ras complexes indicate that the binding site can be expanded upon ligand binding. Nucleotide exchange factors, notably SOS, are required to convert inactive RasGDP to active RasGTP. We determined that the compound-binding site is located at the interface of Ras and SOS. A subset of our Ras-binding molecules indeed inhibited SOS-mediated nucleotide exchange. Further mechanistic studies revealed that through steric hindrance the compounds block the formation of the Ras-SOS complex, a key intermediate of the exchange reaction. At the cellular level, our compounds inhibit the formation of active RasGTP and prevent Ras signaling to downstream effectors. To define the potential clinic utility of these compounds, we performed biological characterization of Ras-driven tumors and identified a subset of Ras mutant tumors that depend on nucleotide exchange factors for the activation of Ras, suggesting a specific profile for the use of exchange inhibitors.
We conclude that the compounds act as competitive inhibitors of nucleotide exchange to prevent the activation of Ras. The discovery of a binding pocket on Ras with functional significance represents a breakthrough finding that will offer a new direction for therapeutic intervention of Ras. Our findings provide new opportunities to target the “undruggable” Ras oncoprotein.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the Second AACR International Conference on Frontiers in Basic Cancer Research; 2011 Sep 14-18; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2011;71(18 Suppl):Abstract nr IA24.
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Affiliation(s)
- T Maurer
- 1Genentech, Inc., South San Francisco, CA
| | | | - A. Oh
- 1Genentech, Inc., South San Francisco, CA
| | - K. Pitts
- 1Genentech, Inc., South San Francisco, CA
| | | | | | - B. Pan
- 1Genentech, Inc., South San Francisco, CA
| | - S. Malek
- 1Genentech, Inc., South San Francisco, CA
| | - D. Stokoe
- 1Genentech, Inc., South San Francisco, CA
| | | | - J. Wu
- 1Genentech, Inc., South San Francisco, CA
| | | | | | - I. Mellman
- 1Genentech, Inc., South San Francisco, CA
| | | | - J. Rudolph
- 1Genentech, Inc., South San Francisco, CA
| | - W. Wang
- 1Genentech, Inc., South San Francisco, CA
| | - G. Fang
- 1Genentech, Inc., South San Francisco, CA
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Fang G, Maurer T, Garrenton L, Skelton N, Fauber B, Malek S, Giannetti A, Jackson P, Rudolph J, Wang W. Drugging the Undruggable Small-molecule Inhibition of Ras Oncoprotein. Eur J Cancer 2011. [DOI: 10.1016/s0959-8049(11)70114-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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22
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Fang G, Li H, Liu X, Wu S. Experimental Investigation of Performances of Microcapsule Phase Change Material for Thermal Energy Storage. Chem Eng Technol 2010. [DOI: 10.1002/ceat.200900224] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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23
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Li N, Fang G, Zhao L, Wang S. Determination of arsenic in foods by flow injection on-line sorption pre-concentration with hydride generation atomic fluorescence spectrometry. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2009; 26:839-46. [DOI: 10.1080/02652030902774631] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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24
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Chao E, Fang G, Beneke M, Ruchala K, Olivera G. SU-GG-J-144: Photon Detection Efficiency of TomoTherapy® Array Detectors and Impact On MVCT Image Quality. Med Phys 2008. [DOI: 10.1118/1.2961693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Abstract
In a variety of tasks performed in construction sites, coordinated operations of multi-vehicles are foreshadowed to outperform the deployment of a single vehicle in terms of increased capacity and flexibility. This paper presents the application of the particle swarm optimization (PSO) algorithm in deriving drive commands, speed and turning, for the vehicles such that they are steered into and maintained in desirable formations according to an assigned task. The PSO is adopted for its implementation simplicity and relaxing the need for analytical system models. To this end, the coordination of vehicles is posed as an optimization problem minimizing the translational and angular errors between the current vehicle positions and their corresponding targets. Inter-vehicle collisions are mitigated, in this work, by employing a behavioural-based reactive scheme together with a dynamical index rescheduling procedure. Simulation results for coordinated multi-vehicle motions, in benchmark formation patterns, are included to demonstrate the effectiveness of the proposed approach.
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Affiliation(s)
- N. M. Kwok
- ARC Centre for Autonomous Systems, Faculty of Engineering, University of Technology, Sydney, Australia
| | - Q. P. Ha
- ARC Centre for Autonomous Systems, Faculty of Engineering, University of Technology, Sydney, Australia
| | - G. Fang
- School of Engineering, University of Western Sydney, Australia
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26
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Joglekar N, Joshi S, Kakde M, Fang G, Cianciola M, Reynolds S, Mehendale S. Acceptability of PRO2000 vaginal gel among HIV un-infected women in Pune, India. AIDS Care 2007; 19:817-21. [PMID: 17573603 DOI: 10.1080/09540120601133576] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Acceptability of PRO2000 Gel, a candidate vaginal microbicide, among participants of its Phase I safety study in Pune, India is reported here. Forty-two eligible women were enrolled in a study requiring twice daily intra-vaginal product use for 14 consecutive days between menses. Acceptability was assessed at study exit through structured questionnaires among 41 participants who completed the product use, and five focus group discussions involving 31 study participants. The participants generally liked the product (40/41, 97.2%), especially its colour (40, 97.2%) and consistency (35, 85.3%). Thirty-four participants reported sexual intercourse within one hour of product use, at least once during the study period and sexual pleasure was reported to be better or unaffected among (30, 88.2%) participants. Nearly 70% did not like its smell and mentioned preference for a product that would be unnoticeable to the male partner. Participating women were concerned about privacy in usage and storage of the product. Acceptability of PRO2000 vaginal gel was good, but its smell will have to be improved. Counselling to address women's concerns about privacy and storage will be crucial. Women's preference for unnoticeable product indicates their empowerment and willingness to accept female-controlled options for HIV prevention.
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Affiliation(s)
- N Joglekar
- National AIDS Research Institute, Indian Council of Medical Research (ICMR), India.
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Conforti L, Fang G, Beirowski B, Wang MS, Sorci L, Asress S, Adalbert R, Silva A, Bridge K, Huang XP, Magni G, Glass JD, Coleman MP. NAD(+) and axon degeneration revisited: Nmnat1 cannot substitute for Wld(S) to delay Wallerian degeneration. Cell Death Differ 2006; 14:116-27. [PMID: 16645633 DOI: 10.1038/sj.cdd.4401944] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The slow Wallerian degeneration protein (Wld(S)), a fusion protein incorporating full-length nicotinamide mononucleotide adenylyltransferase 1 (Nmnat1), delays axon degeneration caused by injury, toxins and genetic mutation. Nmnat1 overexpression is reported to protect axons in vitro, but its effect in vivo and its potency remain unclear. We generated Nmnat1-overexpressing transgenic mice whose Nmnat activities closely match that of Wld(S) mice. Nmnat1 overexpression in five lines of transgenic mice failed to delay Wallerian degeneration in transected sciatic nerves in contrast to Wld(S) mice where nearly all axons were protected. Transected neurites in Nmnat1 transgenic dorsal root ganglion explant cultures also degenerated rapidly. The delay in vincristine-induced neurite degeneration following lentiviral overexpression of Nmnat1 was significantly less potent than for Wld(S), and lentiviral overexpressed enzyme-dead Wld(S) still displayed residual neurite protection. Thus, Nmnat1 is significantly weaker than Wld(S) at protecting axons against traumatic or toxic injury in vitro, and has no detectable effect in vivo. The full protective effect of Wld(S) requires more N-terminal sequences of the protein.
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Affiliation(s)
- L Conforti
- The Babraham Institute, Cambridge CB2 4AT, UK
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Law PK, Haider K, Fang G, Jiang S, Chua F, Lim YT, Sim E. Human VEGF165-myoblasts produce concomitant angiogenesis/myogenesis in the regenerative heart. Mol Cell Biochem 2004; 263:173-8. [PMID: 15524178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
Bioengineering the regenerative heart may provide a novel treatment for heart failure. On May 14, 2002, a 55-year-old man suffering from ischemic myocardial infarction received 25 injections carrying 465 million cGMP-produced pure myoblasts into his myocardium after coronary artery bypass grafting. As on August 28, 2002, his EKG was normal and showed no arrhythmia. His ejection fraction increased by 13%. He no longer experienced shortness of breath and angina as he did before the treatment. Three myogenesis mechanisms were elucidated with 17 human/porcine xenografts using cyclosporine as immunosuppressant. Some myoblasts developed to become cardiomyocytes. Others transferred their nuclei into host cardiomyocytes through natural cell fusion. As yet others formed skeletal myofibers with satellite cells. De novo production of contractile filaments augmented the heart contractility. Human myoblasts transduced with VEGF165 gene produced six times more capillaries in porcine myocardium than in placebo. Xenograft rejection was not observed for up to 20 weeks despite cyclosporine discontinuation at 6 weeks. Pros and cons of autografts vs. allografts are compared to guide future development of heart cell therapy.
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Affiliation(s)
- Peter K Law
- Cell Therapy Research Foundation, Memphis, TN, USA.
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Law PK, Haider K, Fang G, Jiang S, Chua F, Lim Y, Sim E. Human VEGF165-myoblasts produce concomitant angiogenesis/myogenesis in the regenerative heart. Mol Cell Biochem 2004; 263:173-8. [DOI: 10.1023/b:mcbi.0000041859.60354.f5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Xu M, Zhang S, Li S, Wang T, Chen J, Ou N, Fang G, Wang Q, Li J, Zhang X. [Field application of oral artesunate for preventing Schistosoma japonicum infection]. Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi 2003; 17:241-3. [PMID: 12563776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
AIM To assess the preventive effect of oral artesunate against S. japonicum infection. METHODS Residents in two pilots in the schistosomiasis endemic regions, 562 cases in Yanghe pilot, Wangjiang County and 218 cases in Shashan pilot, Guichi City, Anhui Province, were selected for this study. The residents were divided into two groups. Group I received artesunate 6 mg/kg once every 2 weeks for 4 times 2 wk after contacting with infested water from July to September in 1997. Group II received the same dosage of placebo at the corresponding times. Four weeks after the last administration, stool examination using hatching method and Kato's method was conducted to evaluate the effect. RESULTS In Yanghe pilot, 2 cases were hatching positive in the artesunate-treated group with an infection rate of 0.7% (2/273), while 11 cases were stool positive in placebo group with an infection rate of 3.8% (11/289) and a mean EPG of 26.40 +/- 1.49. In Shashan pilot, all cases in artesunate-treated group were stool negative, while 7 cases were stool positive in the placebo group with an infection rate of 6.3% (7/111), and a mean EPG of 14.23 +/- 2.14. The protection rate of artesunate was 80.9% and 100%, respectively, in the two pilots. CONCLUSION Artesunate can protect the residents from S. japonicum infection effectively.
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Affiliation(s)
- M Xu
- Anhui Provincial Institute of Schistosomiasis, Wuhu 241000
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Fang G. Spectrophotometric determination of lead in vegetables with dibromo-p-methyl-carboxysulfonazo. Talanta 2002; 57:1155-60. [DOI: 10.1016/s0039-9140(02)00195-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2001] [Revised: 04/01/2002] [Accepted: 04/12/2002] [Indexed: 11/29/2022]
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Wang MS, Fang G, Culver DG, Davis AA, Rich MM, Glass JD. The WldS protein protects against axonal degeneration: a model of gene therapy for peripheral neuropathy. Ann Neurol 2001; 50:773-9. [PMID: 11761475 DOI: 10.1002/ana.10039] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The WldS mouse is a spontaneous mutant that is characterized by the phenotype of delayed degeneration of transected nerves (slow Wallerian degeneration). Molecular genetic analysis identified a mutation in this animal that codes for a unique protein expressed in brain tissue of WldS mice. We asked whether the WldS phenotype, in addition to delaying axonal degeneration after axotomy, might provide neuroprotection against toxic neuropathy. In dorsal root ganglia (DRG) cultures, neurites from WldS transiently exposed to vincristine not only resisted axonal degeneration but resumed growth after withdrawal of the toxin. Neurites from wild type mice died rapidly and did not recover. To prove that the identified mutation and its protein product are responsible for the WldS phenotype, we used an adenoviral gene transfer system to deliver the WldS to rat DRG neurons. Rat neurons expressing the WldS protein were resistant to vincristine-induced axonal degeneration, confirming the functional significance of the identified gene mutation. These data provide evidence that the WldS protein can be neuroprotective against vincristine neuropathy, and possibly other disorders characterized by axonal degeneration. In addition, delivery of this gene to wild type cells can transfer the WldS phenotype, providing the possibility of "gene therapy" for peripheral neuropathy.
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Affiliation(s)
- M S Wang
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
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Fang G, Burger H, Chappey C, Rowland-Jones S, Visosky A, Chen CH, Moran T, Townsend L, Murray M, Weiser B. Analysis of transition from long-term nonprogressive to progressive infection identifies sequences that may attenuate HIV type 1. AIDS Res Hum Retroviruses 2001; 17:1395-404. [PMID: 11679152 DOI: 10.1089/088922201753197060] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Long-term nonprogressive human immunodeficiency virus type 1 (HIV-1) infection and its transition to progressive infection presents an opportunity to identify the molecular determinants of HIV-1 attenuation and pathogenesis. We studied an individual who underwent a transition from long-term nonprogressive to rapidly progressive infection. Because HIV-1 RNA genomes in plasma represent replicating virus, we developed a technique to clone full-length HIV-1 RNA genomes from plasma and used this technique to obtain clones from this individual before and during the transition. Most clones assayed were infectious, demonstrating that the RNA genomes encoded viable virus. Analysis of 20 complete HIV-1 RNA genomic sequences revealed one major difference between sequences found during the two phases of infection. During the nonprogressive phase, the predominant sequences had a large deletion in an Sp1-binding site and adjacent promoter in the U3 part of the long terminal repeat (LTR); when the infection became progressive, all viruses had intact Sp1 and promoter sequences and were derived from a minor species present earlier. Analysis of 184 clones of the LTR region obtained at five time points spanning a 7-year period confirmed this switch. In an in vitro assay, the deletion downregulated LTR-driven transcription of a reporter gene. In addition, analysis of cytotoxic T lymphocyte (CTL) epitopes predicted from the complete viral RNA genomes revealed multiple potential escape mutants that accumulated by the time of progression. These studies suggest that during the nonprogressive phase, the Sp1 enhancer-promoter deletion is likely to have played a role in decreasing replication, thereby attenuating HIV-1. The accumulation of CTL escape mutants suggests that a breakdown in immunologic surveillance may have allowed proliferation of intact virus, thus leading to rapid disease progression. These data reveal the viral and immune interactions characterizing a transition from long-term nonprogressive to rapidly progressive infection.
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Affiliation(s)
- G Fang
- Wadsworth Center, New York State Department of Health, Albany, New York 12201, USA
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Shi J, Fang G, Sheng Y. [Neo-adjuvant chemotherapy for breast cancer]. Zhonghua Zhong Liu Za Zhi 2001; 23:423-5. [PMID: 11810778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To study the value and indications of a neo-adjuvant chemotherapy for breast cancers. METHODS Forty-three breast cancer patients were given the NF neo-adjuvant chemotherapy (Navelbine 25 mg/m2 and 5-Fu 500 mg/m2) for 3 cycles before the operation. Epirubicin (EPI 40 mg/m2) was added in patients with locally advanced lesions. G-CSF 75 micrograms subcutaneous injection was used to increase the white count as needed. RESULTS The overall response rate was 95.0%. Pre-operative neo-adjuvant chemotherapy showed CR in 3 patients (7.5%) and PR in 35 patients (87.5%) even though 2 patients (5.0%) were refractory. The follow-up ranged from 4 to 37 months (median 20 months). All patients are alive though 4 have developed recurrence or metastasis. CONCLUSION The pre-operative neo-adjuvant chemotherapy may preferably be given in 3 cycles from which those who benefit most are the breast cancer patients with inoperable lesions and who are planned to undergo breast-preserving surgery.
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Affiliation(s)
- J Shi
- Changhai Hospital, Shanghai 200433, China
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Abstract
Anaphase-promoting complex (APC), a ubiquitin ligase, controls both sister chromatid separation and mitotic exit. The APC is activated in mitosis and G1 by CDC20 and CDH1, and inhibited by the checkpoint protein MAD2, a specific inhibitor of CDC20. We show here that a MAD2 homolog MAD2B also inhibits APC. In contrast to MAD2, MAD2B inhibits both CDH1-APC and CDC20-APC. This inhibition is targeted to CDH1 and CDC20, but not directly to APC. Unlike MAD2, whose interaction with MAD1 is required for mitotic checkpoint control, MAD2B does not interact with MAD1, suggesting that MAD2B may relay a different cellular signal to APC.
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Affiliation(s)
- J Chen
- Department of Biological Sciences, Stanford University, Stanford, California 94305-5020, USA
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Wu Y, Yang W, Fang G. [Genetic analysis of hereditary factor VII deficiency from a Chinese pedigree]. Zhonghua Yi Xue Za Zhi 2000; 80:904-6. [PMID: 11236630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE To identify the mutation in coagulation factor VII gene from a Chinese patient with hereditary coagulation factor VII deficiency. METHODS The genomic DNA fragments of FVII gene from a propositus and normal subjects were amplified using polymerase chain reaction (PCR), and analyzed with direct sequencing of PCR products. The PCR amplified genomic DNA fragments of FVII gene from the propositus and her family members were analyzed using restriction enzyme Hgic I. RESULTS The FVII gene sequences of normal subjects were identical to the data published, while a missense mutation (TGT-->GGT) was found at codon 329 in FVII gene of the propositus. The heterozygous condition for the mutation was revealed in her three family members. CONCLUSION We have found a novel mutation (TGT-->GGT) at codon 329 in FVII gene of a patient with hereditary FVII deficiency, which leads to a cystein residue replaced by a glysine. PCR combined with restriction enzyme Hgic I digestion would be a rapid diagnostic method for this mutation.
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Affiliation(s)
- Y Wu
- Research Laboratories, PLA Center for Laboratory Medicine, Fuzhou General Hospital, Fuzhou 350025, China
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Abstract
The spindle checkpoint prevents errors in chromosome segregation by inhibiting anaphase onset until all chromosomes have aligned at the spindle equator through attachment of their sister kinetochores to microtubules from opposite spindle poles. A key checkpoint component is the mitotic arrest-deficient protein 2 (Mad2), which localizes to unattached kinetochores and inhibits activation of the anaphase-promoting complex (APC) through an interaction with Cdc20. Recent studies have suggested a catalytic model for kinetochore function where unattached kinetochores provide sites for assembling and releasing Mad2-Cdc20 complexes, which sequester Cdc20 and prevent it from activating the APC. To test this model, we examined Mad2 dynamics in living PtK1 cells that were either injected with fluorescently labeled Alexa 488-XMad2 or transfected with GFP-hMAD2. Real-time, digital imaging revealed fluorescent Mad2 localized to unattached kinetochores, spindle poles, and spindle fibers depending on the stage of mitosis. FRAP measurements showed that Mad2 is a transient component of unattached kinetochores, as predicted by the catalytic model, with a t(1/2) of approximately 24-28 s. Cells entered anaphase approximately 10 min after Mad2 was no longer detectable on the kinetochores of the last chromosome to congress to the metaphase plate. Several observations indicate that Mad2 binding sites are translocated from kinetochores to spindle poles along microtubules. First, Mad2 that bound to sites on a kinetochore was dynamically stretched in both directions upon microtubule interactions, and Mad2 particles moved from kinetochores toward the poles. Second, spindle fiber and pole fluorescence disappeared upon Mad2 disappearance at the kinetochores. Third, ATP depletion resulted in microtubule-dependent depletion of Mad2 fluorescence at kinetochores and increased fluorescence at spindle poles. Finally, in normal cells, the half-life of Mad2 turnover at poles, 23 s, was similar to kinetochores. Thus, kinetochore-derived sites along spindle fibers and at spindle poles may also catalyze Mad2 inhibitory complex formation.
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Affiliation(s)
- B J Howell
- Department of Biology, CB#3280, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
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Fang G, Kim CN, Perkins CL, Ramadevi N, Winton E, Wittmann S, Bhalla KN. CGP57148B (STI-571) induces differentiation and apoptosis and sensitizes Bcr-Abl-positive human leukemia cells to apoptosis due to antileukemic drugs. Blood 2000; 96:2246-53. [PMID: 10979973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
The differentiation and apoptosis-sensitizing effects of the Bcr-Abl-specific tyrosine kinase inhibitor CGP57148B, also known as STI-571, were determined in human Bcr-Abl-positive HL-60/Bcr-Abl and K562 cells. First, the results demonstrate that the ectopic expression of the p185 Bcr-Abl fusion protein induced hemoglobin in the acute myeloid leukemia (AML) HL-60 cells. Exposure to low-dose cytosine arabinoside (Ara-C; 10 nmol/L) increased hemoglobin levels in HL-60/Bcr-Abl and in the chronic myeloid leukemia (CML) blast crisis K562 cells, which express the p210 Bcr-Abl protein. As compared with HL-60/neo, HL-60/Bcr-Abl and K562 cells were resistant to apoptosis induced by Ara-C, doxorubicin, or tumor necrosis factor-alpha (TNF-alpha), which was associated with reduced processing of caspase-8 and Bid protein and decreased cytosolic accumulation of cytochrome c (cyt c). Exposure to CGP57148B alone increased hemoglobin levels and CD11b expression and induced apoptosis of HL-60/Bcr-Abl and K562 cells. CGP57148B treatment down-regulated antiapoptotic XIAP, cIAP1, and Bcl-x(L), without affecting Bcl-2, Bax, Apaf-1, Fas (CD95), Fas ligand, Abl, and Bcr-Abl levels. CGP57148B also inhibited constitutively active Akt kinase and NFkappaB in Bcr-Abl-positive cells. Attenuation of NFkappaB activity by ectopic expression of transdominant repressor of IkappaB sensitized HL-60/Bcr-Abl and K562 cells to TNF-alpha but not to apoptosis induced by Ara-C or doxorubicin. Importantly, cotreatment with CGP57148B significantly increased Ara-C- or doxorubicin-induced apoptosis of HL-60/Bcr-Abl and K562 cells. This was associated with greater cytosolic accumulation of cyt c and PARP cleavage activity of caspase-3. These in vitro data indicate that combinations of CGP57148B and antileukemic drugs such as Ara-C may have improved in vivo efficacy against Bcr-Abl-positive acute leukemia.
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Affiliation(s)
- G Fang
- H. Lee Moffitt Cancer Center and Research Institute, University of South Florida, Tampa, FL, USA
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Krijgsveld J, Zaat SA, Meeldijk J, van Veelen PA, Fang G, Poolman B, Brandt E, Ehlert JE, Kuijpers AJ, Engbers GH, Feijen J, Dankert J. Thrombocidins, microbicidal proteins from human blood platelets, are C-terminal deletion products of CXC chemokines. J Biol Chem 2000; 275:20374-81. [PMID: 10877842 DOI: 10.1074/jbc.275.27.20374] [Citation(s) in RCA: 246] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Antibacterial proteins are components of the innate immune system found in many organisms and produced by a variety of cell types. Human blood platelets contain a number of antibacterial proteins in their alpha-granules that are released upon thrombin activation. The present study was designed to purify these proteins obtained from human platelets and to characterize them chemically and biologically. Two antibacterial proteins were purified from platelet granules in a two-step protocol using cation exchange chromatography and continuous acid urea polyacrylamide gel electrophoresis and were designated thrombocidin (TC)-1 and TC-2. Characterization of these proteins using mass spectrometry and N-terminal sequencing revealed that TC-1 and TC-2 are variants of the CXC chemokines neutrophil-activating peptide-2 and connective tissue-activating peptide-III, respectively. TC-1 and TC-2 differ from these chemokines by a C-terminal truncation of 2 amino acids. Both TCs, but not neutrophil-activating peptide-2 and connective tissue-activating peptide-III, were bactericidal for Bacillus subtilis, Escherichia coli, Staphylococcus aureus, and Lactococcus lactis and fungicidal for Cryptococcus neoformans. Killing of B. subtilis by either TC appeared to be very rapid. Because TCs were unable to dissipate the membrane potential of L. lactis, the mechanism of TC-mediated killing most probably does not involve pore formation.
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Affiliation(s)
- J Krijgsveld
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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Wu Y, Wang Y, Lan F, Zhu Z, Fang G, Yang W. A novel missense mutation (C329Q) in factor VII gene. Blood 2000; 95:3638-40. [PMID: 10877552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
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Abstract
The peptide transport protein DtpT of Lactococcus lactis was purified and reconstituted into detergent-destabilized liposomes. The kinetics and substrate specificity of the transporter in the proteoliposomal system were determined, using Pro-[(14)C]Ala as a reporter peptide in the presence of various peptides or peptide mimetics. The DtpT protein appears to be specific for di- and tripeptides, with the highest affinities for peptides with at least one hydrophobic residue. The effect of the hydrophobicity, size, or charge of the amino acid was different for the amino- and carboxyl-terminal positions of dipeptides. Free amino acids, omega-amino fatty acid compounds, or peptides with more than three amino acid residues do not interact with DtpT. For high-affinity interaction with DtpT, the peptides need to have free amino and carboxyl termini, amino acids in the L configuration, and trans-peptide bonds. Comparison of the specificity of DtpT with that of the eukaryotic homologues PepT(1) and PepT(2) shows that the bacterial transporter is more restrictive in its substrate recognition.
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Affiliation(s)
- G Fang
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9751 NN Haren, The Netherlands
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Perkins CL, Fang G, Kim CN, Bhalla KN. The role of Apaf-1, caspase-9, and bid proteins in etoposide- or paclitaxel-induced mitochondrial events during apoptosis. Cancer Res 2000; 60:1645-53. [PMID: 10749135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Ectopic overexpression of Apaf-1 (2.5-fold) in human acute myelogenous leukemia HL-60 cells (HL-60/Apaf-1 cells) induced apoptosis and sensitized HL-60/Apaf-1 cells to etoposide- and paclitaxel-induced apoptosis (C. Perkins et al., Cancer Res., 58: 4561-4566, 1998). In this report, we demonstrate that in HL-60/Apaf-1 cells, the activity of caspase-9 and -3 induced by Apaf-1 overexpression was associated with a significant increase (5-fold) in the cytosolic accumulation of cytochrome c (cyt c), loss of mitochondrial membrane potential (deltapsim), and an increase in the reactive oxygen species. These were also associated with the processing of procaspase-8 and Bid (cytosolic, proapoptotic BH3 domain containing protein). Transient transfection of Apaf-1 into the Apaf-1-containing mouse embryogenic fibroblasts (MEFs; Apaf-1+/- MEFs) or Apaf-1-/- MEFs also induced the processing of procaspase-9 and procaspase-8, Bid cleavage, and apoptosis. These events were secondary to the activity of the downstream caspases induced by Apaf-1. This conclusion is supported by the observation that in HL-60/Apaf-1 cells, ectopic expression of dominant negative caspase-9, its inhibitory short isoform caspase-9b, or XIAP or treatment with the caspase inhibitor zVAD (50 microM) inhibited Apaf-1-induced caspase-8 and Bid cleavage, mitochondrial deltapsim, release of cyt c, and apoptosis. In contrast, a transient transfection of dominant negative caspase-8 or CrmA or exposure to caspase-8 inhibitor zIETD-fmk inhibited the processing of procaspase-8 and Bid but did not inhibit the cytosolic accumulation of cyt c in either the untreated HL-60/Apaf-1 cells or the etoposide-treated HL-60/Apaf-1 and HL-60/neo cells. These results indicate that Apaf-1 overexpression lowers the apoptotic threshold by activating caspase-9 and caspase-3. This triggers the mitochondrial deltapsim and cyt c release into the cytosol through a predominant mechanism other than cleavage of caspase-8 and/or Bid. This mechanism may involve a cytosolic mitochondrial permeability transition factor, which may be processed and activated by the downstream effector caspases, thereby completing an amplifying feedback loop, which triggers the mitochondrial events during apoptosis.
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Affiliation(s)
- C L Perkins
- Division of Clinical and Translational Research, Sylvester Comprehensive Cancer Center, University of Miami School of Medicine, Florida 33136, USA
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Luo X, Fang G, Coldiron M, Lin Y, Yu H, Kirschner MW, Wagner G. Structure of the Mad2 spindle assembly checkpoint protein and its interaction with Cdc20. Nat Struct Biol 2000; 7:224-9. [PMID: 10700282 DOI: 10.1038/73338] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The checkpoint protein Mad2 inhibits the activity of the anaphase promoting complex by sequestering Cdc20 until all chromosomes are aligned at the metaphase plate. We report the solution structure of human Mad2 and its interaction with Cdc20. Mad2 possesses a novel three-layered alpha/beta fold with three alpha-helices packed between two beta-sheets. Using deletion mutants we identified the minimal Mad2-binding region of human Cdc20 as a 40-residue segment immediately N-terminal to the WD40 repeats. Mutagenesis and NMR titration experiments show that a C-terminal flexible region of Mad2 is required for binding to Cdc20. Mad2 and Cdc20 form a tight 1:1 heterodimeric complex in which the C-terminal segment of Mad2 becomes folded. These results provide the first structural insight into mechanisms of the spindle assembly checkpoint.
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Affiliation(s)
- X Luo
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, USA
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Perkins C, Kim CN, Fang G, Bhalla KN. Arsenic induces apoptosis of multidrug-resistant human myeloid leukemia cells that express Bcr-Abl or overexpress MDR, MRP, Bcl-2, or Bcl-x(L). Blood 2000; 95:1014-22. [PMID: 10648417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
We investigated the in vitro growth inhibitory and apoptotic effects of clinically achievable concentrations of As(2)O(3) (0.5 to 2.0 micromol/L) against human myeloid leukemia cells known to be resistant to a number of apoptotic stimuli. These included chronic myelocytic leukemia (CML) blast crisis K562 and HL-60/Bcr-Abl cells, which contain p210 and p185 Bcr-Abl, respectively, and HL-60 cell types that overexpress Bcl-2 (HL-60/Bcl-2), Bcl-x(L) (HL-60/Bcl-x(L)), MDR (HL-60/VCR), or MRP (HL-60/AR) protein. The growth-inhibitory IC(50) values for As(2)O(3) treatment for 7 days against all these cell types ranged from 0.8 to 1.5 micromol/L. Exposure to 2 micromol/L As(2)O(3) for 7 days induced apoptosis of all cell types, including HL-60/Bcr-Abl and K562 cells. This was associated with the cytosolic accumulation of cyt c and preapoptotic mitochondrial events, such as the loss of inner membrane potential (DeltaPsim) and the increase in reactive oxygen species (ROS). Treatment with As(2)O(3) (2 micromol/L) generated the activities of caspases, which produced the cleavage of the BH3 domain containing proapoptotic Bid protein and poly (ADP-ribose) polymerase. Significantly, As(2)O(3)-induced apoptosis of HL-60/Bcr-Abl and K562 cells was associated with a decline in Bcr-Abl protein levels, without any significant alterations in the levels of Bcl-x(L), Bax, Apaf-1, Fas, and FasL. Although As(2)O(3 )treatment caused a marked increase in the expression of the myeloid differentiation marker CD11b, it did not affect Hb levels in HL-60/Bcr-Abl, K562, or HL-60/neo cells. However, in these cells, As(2)O(3 )potently induced hyper-acetylation of the histones H3 and H4. These findings characterize As(2)O(3) as a growth inhibiting and apoptosis-inducing agent against a variety of myeloid leukemia cells resistant to multiple apoptotic stimuli.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/biosynthesis
- ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics
- ATP-Binding Cassette Transporters/biosynthesis
- ATP-Binding Cassette Transporters/genetics
- Acetylation/drug effects
- Antineoplastic Agents/pharmacology
- Apoptosis/drug effects
- Apoptotic Protease-Activating Factor 1
- Arsenic Trioxide
- Arsenicals/pharmacology
- Caspases/metabolism
- Cytochrome c Group/metabolism
- Cytosol/metabolism
- Drug Resistance, Multiple
- Drug Resistance, Neoplasm
- Fas Ligand Protein
- Fusion Proteins, bcr-abl/biosynthesis
- Fusion Proteins, bcr-abl/genetics
- Gene Expression Regulation, Leukemic
- Genes, bcl-2
- HL-60 Cells/drug effects
- Histones/metabolism
- Humans
- Immunophenotyping
- K562 Cells/drug effects
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Macrophage-1 Antigen/biosynthesis
- Macrophage-1 Antigen/genetics
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/genetics
- Mitochondria/metabolism
- Multidrug Resistance-Associated Proteins
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- Oxides/pharmacology
- Protein Biosynthesis
- Protein Processing, Post-Translational/drug effects
- Proteins/genetics
- Proto-Oncogene Proteins/biosynthesis
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins c-bcl-2/biosynthesis
- Proto-Oncogene Proteins c-bcl-2/genetics
- bcl-2-Associated X Protein
- bcl-X Protein
- fas Receptor/biosynthesis
- fas Receptor/genetics
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Affiliation(s)
- C Perkins
- Division of Clinical and Translational Research, Sylvester Comprehensive Cancer Center, University of Miami School of Medicine, Miami, FL 33136, USA
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47
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Fang G, Friesen R, Lanfermeijer F, Hagting A, Poolman B, Konings WN. Manipulation of activity and orientation of membrane-reconstituted di-tripeptide transport protein DtpT of Lactococcus lactis. Mol Membr Biol 1999; 16:297-304. [PMID: 10766129 DOI: 10.1080/096876899294517] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The di-tripeptide transport system (DtpT) of Lactococcus lactis was purified to apparent homogeneity by pre-extraction of crude membrane vesicles with octaethylene glycol monodecyl ether (C10E8), followed by solubilization with n-dodecyl-beta-D-maltoside (DDM) and chromatography on a Ni-NTA resin. The DtpT protein was reconstituted into detergent-destabilized preformed liposomes prepared from E. coli phospholipid/phosphatidylcholine. A variety of detergents were tested for their ability to mediate the membrane reconstitution of DtpT and their effectiveness to yield proteoliposomes with a high transport activity. The highest activities were obtained with TX100, C12E8 and DM, whereas DDM yielded relatively poor activities, in particular when this detergent was used at concentrations beyond the onset of solubilization of the preformed liposomes. Parallel with the low activity, significant losses of lipid were observed when the reconstitution was performed at high DDM concentrations. This explained at least part of the reduced transport activity as the DtpT protein was highly dependent on the final lipid-to-protein ratios in the proteoliposomes. Consistent with the difference in mechanism of DDM- and TX100-mediated membrane protein reconstitution, the orientation of the DtpT protein in the membrane was random with DDM and inside-in when TX100 was used. The methodology to determine the orientation of membrane-reconstituted proteins from the accessibility of cysteines for thiol-specific reagents is critically evaluated.
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Affiliation(s)
- G Fang
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands
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48
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Abstract
Proteolysis controls key transitions at several points in the cell cycle. In mitosis, the activation of a large ubiquitin-protein ligase, the anaphase-promoting complex (APC), is required for anaphase initiation and for exit from mitosis. We show that APC is under complex control by a network of regulatory factors, CDC20, CDH1 and MAD2. CDC20 and CDH1 are activators of APC; they bind directly to APC and activate its cyclin ubiquitination activity. CDC20 activates APC at the onset of anaphase in a destruction box (DB)-dependent manner, while CDH1 activates APC from late anaphase through G1 with apparently a much relaxed specificity for the DB. Therefore, CDC20 and CDH1 control both the temporal order of activation and the substrate specificity of APC, and hence regulate different events during mitosis and G1. Counteracting the effect of CDC20, the checkpoint protein MAD2 acts as an inhibitor of APC. When the spindle-assembly checkpoint is activated, MAD2 forms a ternary complex with CDC20 and APC to prevent activation of APC, and thereby arrests cells at prometaphase. Thus, a combination of positive and negative regulators establishes a regulatory circuit of APC, ensuring an ordered progression of events through cell division.
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Affiliation(s)
- G Fang
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
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49
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Kelly MK, Miller KF, Fang G, Feng G. When days are numbered: calendar structure and the development of calendar processing in English and Chinese. J Exp Child Psychol 1999; 73:289-314. [PMID: 10419645 DOI: 10.1006/jecp.1999.2503] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Unlike English, Chinese uses a numerical system for naming months and days. This study explored whether this difference in naming affects the development of simple calendar calculation. Eight- and 10-year-old children as well as undergraduates in China and the United States were asked to name the day or month that comes a specified time before or after a given day or month. In each age group Chinese speakers primarily used calculation based on calendar names to solve these tasks, while English speakers primarily resorted to reciting the names. The magnitude of these differences was substantial; on difficult tasks Chinese fourth graders performed at speeds comparable to those of English-speaking adults. Implications for models of how linguistic structure affects cognition are discussed.
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Affiliation(s)
- M K Kelly
- Department of Psychology, University of Illinois at Urbana-Champaign, Champaign 61820-6267, USA
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50
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Fang G, Yang YL, Li JS, Zhang ZX. R-dl-verapamil downmodulates multidrug resistance of KBv200 cells to vincristine and doxorubicin. Zhongguo Yao Li Xue Bao 1999; 20:647-50. [PMID: 10678132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
AIM To study the attenuation of multidrug resistance (MDR) by R-dl-verapamil (R-Ver) and the acute animal toxicity of R-Ver, and to compare these results of R-Ver with the results of dl-verapamil (Ver). METHODS Cytotoxicity was determined by tetrazolium (MTT) assay. Cellular accumulation of doxorubicin (Dox) was measured by fluorescence spectrophotometry. Acute animal toxicity was tested by i.p. drug administration in BALB/c mice. RESULTS R-Ver attenuated MDR of KBv200 cells to vincristine (VCR) and Dox. This attenuation ability was dose-related, and was also dependent on drug exposure time. R-Ver 1.25 mumol.L-1 increased the sensitivity of KBv200 cells to VCR (P < 0.01) with a 24-h period of drug exposure. R-Ver downmodulated MDR and increased cellular Dox accumulation of KBv200 cells as effectively as Ver, but possessed lower acute toxicity in BALB/c mice. While LD50 of Ver was 60 (49-73) mg.kg-1, LD50 of R-Ver was 166 (137-202) mg.kg-1. CONCLUSION R-Ver downmodulated the MDR to VCR and Dox at 1.25 mumol.L-1, and this effect on VCR can be realized with drug exposure duration of 24 h.
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Affiliation(s)
- G Fang
- Nanjing University School of Medicine, China.
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