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Deng C, Xiong C, Huo J, Liu Y, Man Y, Qu Y. Posterior open wound healing in immediate implant placement using reactive soft tissue versus absorbable collagen sponge: a retrospective cohort study. Int J Oral Maxillofac Surg 2024; 53:436-443. [PMID: 38103945 DOI: 10.1016/j.ijom.2023.11.009] [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: 03/19/2023] [Revised: 10/13/2023] [Accepted: 11/15/2023] [Indexed: 12/19/2023]
Abstract
The soft and hard tissue healing of open wounds in immediate implant placement are yet to be explored. The aim of this study was to compare the clinical outcomes of open wound healing using reactive soft tissue (RST) and absorbable collagen sponge (ACS). Forty implants placed immediately in posterior sockets were included; autologous RST was used in 20 and ACS substitute was used in 20. Soft tissue healing was primarily assessed through a novel scoring system and the evaluation of gingival recession. The horizontal bone width (HBW) and interproximal marginal bone level (MBL) were measured on radiographs to observe the hard tissue healing. No significant difference in total soft tissue healing score was observed at 2 weeks postoperatively. Notably, the ACS group showed better tissue colour (P = 0.016) but worse fibrous repair (P = 0.043) scores than the RST group. Gingival recession levels were comparable in the two groups, both before tooth extraction and after placement of the restoration. Regarding hard tissue, HBW and MBL changes showed no intergroup differences. Within the limitations of this study, both RST and ACS seemed effective for open wound closure, achieving ideal soft and hard tissue healing in immediate implant placement.
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Affiliation(s)
- C Deng
- State Key Laboratory of Oral Diseases and National Center for Stomatology and National Clinical Research Center for Oral Diseases and Department of Oral Implantology, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - C Xiong
- State Key Laboratory of Oral Diseases and National Center for Stomatology and National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - J Huo
- State Key Laboratory of Oral Diseases and National Center for Stomatology and National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Y Liu
- State Key Laboratory of Oral Diseases and National Center for Stomatology and National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Y Man
- State Key Laboratory of Oral Diseases and National Center for Stomatology and National Clinical Research Center for Oral Diseases and Department of Oral Implantology, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Y Qu
- State Key Laboratory of Oral Diseases and National Center for Stomatology and National Clinical Research Center for Oral Diseases and Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.
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Xiong C, Chen P, Jiang ML, Chang BW, Niu CS. [Early brain imaging changes and its influence on electrode impedance after implantation of 3.0 T MRI-compatible deep brain stimulation system in Parkinson's disease subthalamic nucleus]. Zhonghua Yi Xue Za Zhi 2023; 103:3809-3815. [PMID: 38123221 DOI: 10.3760/cma.j.cn112137-20231009-00682] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Objective: To analyze the imaging changes of in the early period after subthalamic nucleus (STN) deep brain stimulation (DBS) surgery for Parkinson's disease (PD) and its impact on electrode impedance by the application of 3.0T MRI-compatible devices. Methods: A retrospective analysis was performed for the data of 43 PD patients who underwent 3.0T MRI-compatible STN-DBS surgery from October 2022 to April 2023 at the First Affiliated Hospital of USTC(Anhui Provincial Hospital), including 27 males and 16 females, aged 43-68 (56±5) years. All patients underwent postoperative 3.0T MRI, CT scans,and impedance measurements 1 week postoperatively.Fifteen patients underwent 3.0T MRI and impedance measurements 1 month postoperatively. The differences in impedance of electrode contacts before and after the 3.0T MRI scans were compared. The occurrence of peri-lead cerebral edema (PLE) in patients was analyzed, as well as the differences in PLE detection rates between the two imaging methods, and the differences in the incidence and volume of PLE at different microelectrode recordings, the occurrence and detection of postoperative PLE, and different microelectrode recording (MER) times and different time nodes were compared. The correlation between electrode impedance and the volume of edema around the nucleus was analyzed. Results: All 43 patients successfully underwent surgery, with a total of 86 electrodes implanted. There was no significant difference in electrode impedance values before and after the 3.0T MRI examinations at 1 week and 1 month postoperatively. The PLE detection rate with 3.0T MRI was 95.12%(39/43), which is significantly higher than that of CT imaging 17.07% (7/43)(χ2=50.705, P<0.001). One week after surgery, the incidence and volume of PLE were higher in the multiple MER group compared with the single MER group, but the difference was not statistically significant. The volume of PLE [M(Q1, Q3) 0 (0, 1.211) cm3] at 1 month was significantly smaller than that at 1 week [0.243 (0, 2.914) cm3] (Z=-3.408, P=0.001). The impedance of electrode contacts within 1 month postoperatively showed a trend of initial decrease followed by an increase, which was negatively correlated with SE volume(r=-0.317, P=0.014). Conclusions: The application of 3.0T MRI-compatible DBS devices in the surgical treatment of PD patients improves the accuracy of early postoperative imaging assessment. The electrode impedance is more stable as the edema around the nucleus subsided at 1 month after surgery, which is suitable for the first program control.
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Affiliation(s)
- C Xiong
- Department of Neurosurgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Anhui Provincial Key Laboratory of Brain Function and Disease, Hefei 230001, China
| | - P Chen
- Department of Neurosurgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Anhui Provincial Key Laboratory of Brain Function and Disease, Hefei 230001, China
| | - M L Jiang
- Department of Neuroelectrophysiology, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230036, China
| | - B W Chang
- Department of Neurosurgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Anhui Provincial Key Laboratory of Brain Function and Disease, Hefei 230001, China
| | - C S Niu
- Department of Neurosurgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Anhui Provincial Key Laboratory of Brain Function and Disease, Hefei 230001, China
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Chen P, Xiong C, Jiang ML, Zhuang HX, Mei JM, Niu CS. [Analysis of complications and learning curve effects related to deep brain stimulation surgery in 822 Parkinson's disesase patients with the same surgeon]. Zhonghua Yi Xue Za Zhi 2023; 103:3822-3827. [PMID: 38123223 DOI: 10.3760/cma.j.cn112137-20231030-00945] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Objective: To analyze the complications related to deep brain stimulation(DBS) surgery in Parkinson's disease(PD) patients and to determine whether there is a learning curve effect in terms of complications. Methods: Retrospective analysis of the DBS surgical data of 822 PD patients performed by the same surgeon at the First Affiliated Hospital of the University of Science and Technology of China (Anhui Provincial Hospital) from December 2012 to December 2022. The complications related to DBS were evaluated and analyzed the complications of every 100 DBS surgery were further analyzed. Results: A total of 822 PD patients, 453 males and 369 females, aged 31-80 years old, were included. The minimum follow-up period after DBS surgery is 6 months. Surgical related complications occurred in 55 patients (6.69%), including 5 patients (0.61%) with slight bleeding around the electrode, 1 patient (0.12%) with cerebral infarction, 4 patients (0.49%) with postoperative epilepsy, 42 patients (5.11%) with postoperative delirium, 2 patients (0.24%) with respiratory distress, and 1 patient (0.12%) with acute cardiac insufficiency. There were 16 cases (1.94%) of hardware related complications in DBS, of which 4 cases (0.48%) had infection, 1 case (0.12%) had a broken angle at the connection between the pulse generator and the extension wire, 8 cases (0.97%) had an excessively tight extension wire, and 3 cases (0.36%) had an IPG bag hematoma. In the infected cases, 2 patients removed IPG and extension wires. There were 7 cases (0.85%) of stimulus related complications, including 4 cases (0.61%) with programmed sensory abnormalities, 1 case (0.12%) with postoperative abnormal movements and dance like movements, and 2 cases (0.24%) with psychiatric symptoms. A comprehensive analysis was conducted on the above complications, among which 8 cases (0.97%) were relatively serious complications. After active treatment, satisfactory results were achieved, and none of them affected the patient's DBS treatment effect and no patients died. For every 100 cases of DBS surgery complications were analyzed, the percentage of complications decreased significantly from 14.50% (58 cases) in the first 400 cases to 4.73% (20 cases) in the last 400 cases (P<0.001). Conclusion: DBS surgery is safe and has an acceptable low incidence of complications. The incidence of complications also decreases with the accumulation of experience, showing a learning curve effect.
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Affiliation(s)
- P Chen
- Department of Neurosurgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Anhui Provincial Key Laboratory of Brain Function and Disease, Hefei 230001, China
| | - C Xiong
- Department of Neuroelectrophysiology, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230036, China
| | - M L Jiang
- Department of Neuroelectrophysiology, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230036, China
| | - H X Zhuang
- Department of Neurosurgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Anhui Provincial Key Laboratory of Brain Function and Disease, Hefei 230001, China
| | - J M Mei
- Department of Neurosurgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Anhui Provincial Key Laboratory of Brain Function and Disease, Hefei 230001, China
| | - C S Niu
- Department of Neurosurgery, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Anhui Provincial Key Laboratory of Brain Function and Disease, Hefei 230001, China
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Henriques-Santos BM, Xiong C, Pietrantonio PV. Automated analysis of feeding behaviors of females of the mosquito Aedes aegypti using a modified flyPAD system. Sci Rep 2023; 13:20188. [PMID: 37980438 PMCID: PMC10657447 DOI: 10.1038/s41598-023-47277-4] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 11/11/2023] [Indexed: 11/20/2023] Open
Abstract
Mosquitoes present a global health challenge due to their ability to transmit human and animal pathogens upon biting and blood feeding. The investigation of tastants detected by mosquitoes and their associated feeding behaviors is needed to answer physiological and ecological questions that could lead to novel control methods. A high-throughput system originally developed for research in fruit flies feeding behavior, the flyPAD, was adapted and tested for behaviors associated with the interaction or consumption of liquid diets offered to females of the mosquito Aedes aegypti Liverpool strain. Females were given water, sucrose solution and sheep blood in choice and non-choice assays. The volume ingested was evaluated with fluorescein. The placement of the system on a heated surface allowed blood consumption, and without females puncturing a membrane. The flyPAD system recorded nine feeding behavioral variables, of which the number of sips and number of activity bouts correlated with meal volume ingested for both sucrose solution and blood. The adaptation to mosquitoes of the flyPAD system differentiated feeding behavior variables between two feeding deterrents, capsaicin, and caffeine. The flyPAD has potential to quickly assess diverse tastants in both sucrose and blood and may contribute to characterizing more precisely their mode of action.
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Affiliation(s)
| | - Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX, 77843-2475, USA
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Vermunt L, Sutphen C, Dicks E, de Leeuw DM, Allegri R, Berman SB, Cash DM, Chhatwal JP, Cruchaga C, Day G, Ewers M, Farlow M, Fox NC, Ghetti B, Graff-Radford N, Hassenstab J, Jucker M, Karch CM, Kuhle J, Laske C, Levin J, Masters CL, McDade E, Mori H, Morris JC, Perrin RJ, Preische O, Schofield PR, Suárez-Calvet M, Xiong C, Scheltens P, Teunissen CE, Visser PJ, Bateman RJ, Benzinger TLS, Fagan AM, Gordon BA, Tijms BM. Axonal damage and astrocytosis are biological correlates of grey matter network integrity loss: a cohort study in autosomal dominant Alzheimer disease. medRxiv 2023:2023.03.21.23287468. [PMID: 37016671 PMCID: PMC10071836 DOI: 10.1101/2023.03.21.23287468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/06/2023]
Abstract
Brain development and maturation leads to grey matter networks that can be measured using magnetic resonance imaging. Network integrity is an indicator of information processing capacity which declines in neurodegenerative disorders such as Alzheimer disease (AD). The biological mechanisms causing this loss of network integrity remain unknown. Cerebrospinal fluid (CSF) protein biomarkers are available for studying diverse pathological mechanisms in humans and can provide insight into decline. We investigated the relationships between 10 CSF proteins and network integrity in mutation carriers (N=219) and noncarriers (N=136) of the Dominantly Inherited Alzheimer Network Observational study. Abnormalities in Aβ, Tau, synaptic (SNAP-25, neurogranin) and neuronal calcium-sensor protein (VILIP-1) preceded grey matter network disruptions by several years, while inflammation related (YKL-40) and axonal injury (NfL) abnormalities co-occurred and correlated with network integrity. This suggests that axonal loss and inflammation play a role in structural grey matter network changes. Key points Abnormal levels of fluid markers for neuronal damage and inflammatory processes in CSF are associated with grey matter network disruptions.The strongest association was with NfL, suggesting that axonal loss may contribute to disrupted network organization as observed in AD.Tracking biomarker trajectories over the disease course, changes in CSF biomarkers generally precede changes in brain networks by several years.
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Li QF, Song LJ, Yang YY, Dong PP, Mei CJ, Li YX, Zhang JF, Xiong C, Yu CX, Yang K. [Recombinant Schistosoma japonicum egg ribonuclease SjCP1412 inhibits the activation of LX-2 hepatic stellate cells in vitro]. Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi 2023; 34:566-579. [PMID: 36642896 DOI: 10.16250/j.32.1374.2022163] [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] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVE To investigate the effect of recombinant Schistosoma japonicum egg ribonuclease SjCP1412 (rSjCP1412) on proliferation, cell cycle, apoptosis and activation of human hepatic stellate cells LX-2 in vitro, and explore the underlying mechanisms. METHODS The rSjCP1412 protein was expressed in Escherichia coli BL21 by prokaryotic expression, and the highly purified soluble rSjCP1412 protein was prepared by Ni NTA affinity chromatography and urea gradient refolding dialysis. Yeast RNA was digested using 12.5, 25.0, 50.0 µg rSjCP1412 proteins at 37 °C for 2, 3, 4 h, and the enzymatic products were electrophoresed on 1.5% agarose gel to observe the RNAase activity of rSjCP1412 protein. The proliferation of LX-2 cells stimulated by different doses of rSjCP1412 protein for 48 hours was measured using CCK-8 assay, and the apoptosis of LX-2 cells stimulated by different doses of rSjCP1412 protein for 48 hours was detected using the Annexin V-FITC/PI double staining, while the percentage of LX-2 cells at G0/G1, S and G2/M phases of cell cycle following stimulation with different doses of rSjCP1412 protein for 48 h was detected by DAPI staining. The type I collagen, type III collagen and α-smooth muscle actin (α-SMA) mRNA expression was quantified using quantitative florescent real-time PCR (qPCR) assay and Western blotting at transcriptional and translational levels in LX-2 cells following stimulation with different doses of rSjCP1412 protein for 48 h, while soluble egg antigen (SEA) served a positive control and PBS without rSjCP1412 protein as a normal control in the above experiments. The expression of collagen I, α-SMA and Smad4 protein was determined using Western blotting in LX-2 cells following stimulation with rSjCP1412 protein, transforming growth factor-β1 (TGF-β1) alone or in combination, to examine the signaling for the effect of rSjCP1412 protein on LX-2 cells. RESULTS The rSjCP1412 protein was successfully expressed and the highly purified soluble rSjCP1412 protein was prepared, which had a RNase activity. Compared with the normal group, the survival rates of LX-2 cells significantly decreased post-treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein and SEA for 48 h (F = 22.417 and 20.448, both P values < 0.05). The apoptotic rates of LX-2 cells significantly increased post-treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein for 48 h (F = 11.350, P < 0.05), and treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein for 48 h resulted in arrest of LX-2 cells in G0/G1 phase (F = 20.710, P < 0.05). Treatment with 12.5, 25.0, 50.0 µg/mL rSjCP1412 protein for 48 h caused a significant reduction in relative expression levels of collagen I (F = 11.340, P < 0.05), collagen III (F = 456.600, P < 0.05) and α-SMA mRNA (F = 23.100, P < 0.05) in LX-2 cells, and both rSjCP1412 protein and SEA treatment caused a significant reduction in collagen I (F = 1 302.000, P < 0.05), α-SMA (F = 49.750, P < 0.05) and Smad4 protein expression (F = 52.420, P < 0.05) in LX-2 cells. In addition, rSjCP1412 protein treatment inhibited collagen I (F = 66.290, P < 0.05), α-SMA (F = 31.300, P < 0.05) and Smad4 protein expression (F = 27.010, P < 0.05) in LX-2 cells activated by TGF-β1. CONCLUSIONS rSjCP1412 protein may induce apoptosis of LX-2 cells and inhibit proliferation, cell cycle and activation of LX-2 cells through down-regulating Smad4 signaling molecules.
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Affiliation(s)
- Q F Li
- School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China.,Co-first authors
| | - L J Song
- School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China.,National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214064, China.,Co-first authors
| | - Y Y Yang
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214064, China
| | - P P Dong
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214064, China
| | - C J Mei
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214064, China
| | - Y X Li
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214064, China
| | - J F Zhang
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214064, China
| | - C Xiong
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214064, China
| | - C X Yu
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214064, China
| | - K Yang
- School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China.,National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214064, China
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Xiong C, Baker D, Pietrantonio P. A "Dual-Addition" Calcium Fluorescence Assay for the High-Throughput Screening of Recombinant G Protein-Coupled Receptors. J Vis Exp 2022. [PMID: 36533828 DOI: 10.3791/64505] [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] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
G protein-coupled receptors (GPCRs) represent the largest superfamily of receptors and are the targets of numerous human drugs. High-throughput screening (HTS) of random small molecule libraries against GPCRs is used by the pharmaceutical industry for target-specific drug discovery. In this study, an HTS was employed to identify novel small-molecule ligands of invertebrate-specific neuropeptide GPCRs as probes for physiological studies of vectors of deadly human and veterinary pathogens. The invertebrate-specific kinin receptor was chosen as a target because it regulates many important physiological processes in invertebrates, including diuresis, feeding, and digestion. Furthermore, the pharmacology of many invertebrate GPCRs is poorly characterized or not characterized at all; therefore, the differential pharmacology of these groups of receptors with respect to the related GPCRs in other metazoans, especially humans, adds knowledge to the structure-activity relationships of GPCRs as a superfamily. An HTS assay was developed for cells in 384-well plates for the discovery of ligands of the kinin receptor from the cattle fever tick, or southern cattle tick, Rhipicephalus microplus. The tick kinin receptor was stably expressed in CHO-K1 cells. The kinin receptor, when activated by endogenous kinin neuropeptides or other small molecule agonists, triggers Ca2+ release from calcium stores into the cytoplasm. This calcium fluorescence assay combined with a "dual-addition" approach can detect functional agonist and antagonist "hit" molecules in the same assay plate. Each assay was conducted using drug plates carrying an array of 320 random small molecules. A reliable Z' factor of 0.7 was obtained, and three agonist and two antagonist hit molecules were identified when the HTS was at a 2 µM final concentration. The calcium fluorescence assay reported here can be adapted to screen other GPCRs that activate the Ca2+ signaling cascade.
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Affiliation(s)
| | - Dwight Baker
- Department of Biochemistry and Biophysics, Texas A&M University
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Piccirella S, Van Neste L, Fowler C, Masters CL, Fripp J, Doecke JD, Xiong C, Uberti D, Kinnon P. A Conformational Variant of p53 (U-p53AZ) as Blood-Based Biomarker for the Prediction of the Onset of Symptomatic Alzheimer's Disease. J Prev Alzheimers Dis 2022; 9:469-479. [PMID: 35841248 DOI: 10.14283/jpad.2022.52] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Ongoing research seeks to identify blood-based biomarkers able to predict onset and progression of Alzheimer's disease (AD). OBJECTIVE The unfolded conformational variant of p53 (U-p53AZ), previously observed in AD individuals, was evaluated in plasma samples from individuals participating in the Australian Imaging, Biomarkers and Lifestyle (AIBL) cohort for diagnostic and prognostic assessment, validated on a neuropsychological-based diagnosis, over the course of six years. DESIGN Retrospective Longitudinal Prognostic biomarker study. SETTING Single-center study based on the AIBL cohort. PARTICIPANTS 482 participants of the AIBL cohort, aged 60-85 years, without uncontrolled diabetes, vascular disease, severe depression or psychiatric illnesses. MEASUREMENTS The AlzoSure® Predict test, consisting of immunoprecipitation (IP) followed by liquid chromatography (LC) tandem mass spectrometry (MS/MS), was performed to quantify the AZ 284® peptide as readout of U-p53AZ and compared with an independent neuropsychological diagnosis. The amyloid load via amyloid β-positron emission tomography (Aβ-PET) and supporting clinical information were included where possible. RESULTS U-p53AZ diagnostic and prognostic performance was assessed in both time-independent and time-dependent (36, 72 and 90 months following initial sampling) analyses. Prognostic performance of Aβ-PET and survival analyses with different risk factors (gender, Aβ-PET and APOE ε4 allele status) were also performed. U-p53AZ differentiated neuropsychologically graded AD from non-AD samples, and its detection at intermediate/high levels precisely identified present and future symptomatic AD. In both time-independent and time-dependent prognostic analyses U-p53AZ achieved area under the curve (AUC) >98%, significantly higher than Aβ-PET AUCs (between 84% and 93%, P respectively <0.0001 and <0.001). As single factor, U-p53AZ could clearly determine the risk of AD neuropsychological diagnosis over time (low versus intermediate/high U-p53AZ hazard ratio=2.99). Proportional hazards regression analysis identified U-p53AZ levels as a major independent predictor of AD onset. CONCLUSIONS These findings support use of U-p53AZ as blood-based biomarker predicting whether individuals would reach neuropsychologically-defined AD within six years prior to AD diagnosis. Integration of U-p53AZ in screening processes could support refined participant stratification for interventional studies.
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Wulff JP, Temeyer KB, Tidwell JP, Schlechte KG, Xiong C, Lohmeyer KH, Pietrantonio PV. Pyrokinin receptor silencing in females of the southern cattle tick Rhipicephalus (Boophilus) microplus is associated with a reproductive fitness cost. Parasit Vectors 2022; 15:252. [PMID: 35818078 PMCID: PMC9272880 DOI: 10.1186/s13071-022-05349-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 05/28/2022] [Indexed: 12/12/2022] Open
Abstract
Background Rhipicephalusmicroplus is the vector of deadly cattle pathogens, especially Babesia spp., for which a recombinant vaccine is not available. Therefore, disease control depends on tick vector control. However, R.microplus populations worldwide have developed resistance to available acaricides, prompting the search for novel acaricide targets. G protein-coupled receptors (GPCRs) are involved in the regulation of many physiological processes and have been suggested as druggable targets for the control of arthropod vectors. Arthropod-specific signaling systems of small neuropeptides are being investigated for this purpose. The pyrokinin receptor (PKR) is a GPCR previously characterized in ticks. Myotropic activity of pyrokinins in feeding-related tissues of Rhipicephalussanguineus and Ixodesscapularis was recently reported. Methods The R.microplus pyrokinin receptor (Rhimi-PKR) was silenced through RNA interference (RNAi) in female ticks. To optimize RNAi, a dual-luciferase assay was applied to determine the silencing efficiency of two Rhimi-PKR double-stranded RNAs (dsRNA) prior to injecting dsRNA in ticks to be placed on cattle. Phenotypic variables of female ticks obtained at the endpoint of the RNAi experiment were compared to those of control female ticks (non-injected and beta-lactamase dsRNA-injected). Rhimi-PKR silencing was verified by quantitative reverse-transcriptase PCR in whole females and dissected tissues. Results The Rhimi-PKR transcript was expressed in all developmental stages. Rhimi-PKR silencing was confirmed in whole ticks 4 days after injection, and in the tick carcass, ovary and synganglion 6 days after injection. Rhimi-PKR silencing was associated with an increased mortality and decreased weight of both surviving females and egg masses (P < 0.05). Delays in repletion, pre-oviposition and incubation periods were observed (P < 0.05). Conclusions Rhimi-PKR silencing negatively affected female reproductive fitness. The PKR appears to be directly or indirectly associated with the regulation of female feeding and/or reproductive output in R.microplus. Antagonists of the pyrokinin signaling system could be explored for tick control. Graphical abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-022-05349-w.
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Affiliation(s)
- Juan P Wulff
- Department of Entomology, Texas A&M University, College Station, TX, 77843-2475, USA
| | - Kevin B Temeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), 2700 Fredericksburg Road, Kerrville, TX, 78028-9184, USA
| | - Jason P Tidwell
- Cattle Fever Tick Research Laboratory, USDA-ARS, 22675 N. Moorefield Rd. Building 6419, Edinburg, TX, 78541-5033, USA
| | - Kristie G Schlechte
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), 2700 Fredericksburg Road, Kerrville, TX, 78028-9184, USA
| | - Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX, 77843-2475, USA
| | - Kimberly H Lohmeyer
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), 2700 Fredericksburg Road, Kerrville, TX, 78028-9184, USA
| | - Patricia V Pietrantonio
- Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), 2700 Fredericksburg Road, Kerrville, TX, 78028-9184, USA.
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Xiong C, Wulff JP, Nachman RJ, Pietrantonio PV. Myotropic Activities of Tick Pyrokinin Neuropeptides and Analog in Feeding Tissues of Hard Ticks (Ixodidae). Front Physiol 2022; 12:826399. [PMID: 35242048 PMCID: PMC8887807 DOI: 10.3389/fphys.2021.826399] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 12/20/2021] [Indexed: 12/19/2022] Open
Abstract
Neuropeptides regulate many important physiological processes in animals. The G protein-coupled receptors of corresponding small neuropeptide ligands are considered promising targets for controlling arthropod pests. Pyrokinins (PKs) are pleiotropic neuropeptides that, in some insect species, stimulate muscle contraction and modulate pheromone biosynthesis, embryonic diapause, and feeding behavior. However, their function remains unknown in ticks. In this study, we reported the myotropic activity of tick endogenous PKs and a PK agonist analog, PK-PEG8 (MS[PEG8]-YFTPRLa), on feeding tissues of two tick species representing the family Ixodidae lineages, namely, Prostriata (Ixodes scapularis) and Metastriata (Rhipicephalus sanguineus). First, we predicted the sequences of two periviscerokinins (PVK), one with a derived ending RNa and five PKs encoded by the CAPA peptide precursor from R. sanguineus and found the encoded PKs were identical to those of R. microplus identified previously. The pharynx-esophagus of both tick species responded with increased contractions to 10 μM of the endogenous PK as well as to PK-PEG8 but not to the scrambled PK peptide, as expected. A dose-dependent myotropic activity of the PK-PEG8 was found for both tick species, validating the analog activity previously found in the pyrokinin recombinant receptor assay. In agreement with the tissue activity elicited, we quantified the relative transcript abundance of R. sanguineus PK receptor in unfed female ticks and found it was the highest in the feeding tissues extracted from the capitulum and lowest in the reproductive tissue. This is the first report of the activity of pyrokinins in ticks. These findings strongly indicate the potential role of PKs in regulating tick blood feeding and therefore, making the tick PK receptor a potential target for interference.
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Affiliation(s)
- Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX, United States
| | - Juan P Wulff
- Department of Entomology, Texas A&M University, College Station, TX, United States
| | - Ronald J Nachman
- Insect Neuropeptide Lab, Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, USDA-ARS, College Station, TX, United States
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Xiong C, Yang Y, Nachman RJ, Pietrantonio PV. Tick CAPA propeptide cDNAs and receptor activity of endogenous tick pyrokinins and analogs: Towards discovering pyrokinin function in ticks. Peptides 2021; 146:170665. [PMID: 34600038 DOI: 10.1016/j.peptides.2021.170665] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/16/2021] [Accepted: 09/27/2021] [Indexed: 02/06/2023]
Abstract
Pyrokinins (PKs) are pleiotropic neuropeptides with significant roles in invertebrate physiology. Although functions of PKs are known in insects, there is a lack of knowledge of PK-encoding genes and PKs functions in ticks. Herein the first tick cDNAs of the capability (capa) gene were cloned from the southern cattle tick, Rhipicephalus microplus (Acari: Ixodidae), and the blacklegged tick, Ixodes scapularis. Each cDNA encoded one periviscerokinin and five different pyrokinins. Two PKs were identical in sequence in the two species. The three PKs unique to R. microplus (Rhimi-CAPA-PK1, -PK2, and -PK5) were tested on the recombinant R. microplus pyrokinin receptor using a calcium bioluminescence assay. The Rhimi-CAPA-PKs acted as agonists with EC50s ranging from 101-188 nM. Twenty PK analogs designed for enhanced bioavailability and biostability were tested on the receptor. Five of these were designed based on the sequences of the three unique Rhimi-CAPA-PKs. Eight PK analogs were also agonists; four of them were full agonists that exhibited comparable efficacy to the native Rhimi-CAPA-PKs, with EC50 ranging from 401 nM-1.9 μM. The structure-activity relationships (SAR) of all analogs were analyzed. Our results suggested that a positively charged, basic lysine at the variable position X of the PK active core (FXPRLamide) conferred enhanced affinity to the analogs in their interaction with the tick receptor. These analogs are promising tools to elucidate the pyrokinin function in ticks in vivo as these analogs are expected to have prolonged hemolymph residence time in comparison to the native peptides.
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Affiliation(s)
- Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX, 77843, USA
| | - Yunlong Yang
- Department of Entomology, Texas A&M University, College Station, TX, 77843, USA.
| | - Ronald J Nachman
- Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, 2881 F/B Road, College Station, TX, 77845, USA.
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Xiong C, Baker D, Pietrantonio PV. A random small molecule library screen identifies novel antagonists of the kinin receptor from the cattle fever tick, Rhipicephalus microplus (Acari: Ixodidae). Pest Manag Sci 2021; 77:2238-2251. [PMID: 33415807 DOI: 10.1002/ps.6249] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 12/17/2020] [Accepted: 01/07/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND The southern cattle tick, Rhipicephalus microplus, is a primary vector of the deadly bovine disease babesiosis. Worldwide populations of ticks have developed resistance to acaricides, underscoring the need for novel target discovery for tick control. The arthropod-specific R. microplus kinin receptor is such a target, previously validated by silencing, which resulted in female reproductive fitness costs, including a reduced percentage of eggs hatching. RESULTS In order to identify potent small molecules that bind and activate or inhibit the kinin receptor, a high-throughput screening (HTS) assay was developed using a CHO-K1 cell line expressing the recombinant tick kinin receptor (BMLK3 ). A total of ~20 000 molecules from a random in-house small molecule library were screened in a 'dual-addition' calcium fluorescence assay. This was followed by dose-response validation of the hit molecules identified both from HTS and an in silico screen of ~390 000 molecules. We validated 29 antagonists, 11 of them were full antagonists with IC50 values between 0.67 and 8 μmol L-1 . To explore the structure-activity relationships (SAR) of the small molecules, we tested the activities of seven analogs of the most potent identified antagonist, additionally discovering three full antagonists and four partial antagonists. These three potent antagonists (IC50 < 3.2 μmol L-1 ) were validated in vitro using the recombinant mosquito kinin receptor and showed similar antagonistic activities. In vivo, these three compounds also inhibited the mosquito hindgut contraction rate induced by a myotropic kinin agonist analog 1728. CONCLUSION Antagonists identified in this study could become pesticide leads and are reagents for probing the kinin signaling system. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX, USA
| | - Dwight Baker
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
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Wen Y, Xiang G, Xiong C, Yang Y, Zhang J. Isolated left subclavian artery with right aortic arch and bilateral ductus arteriosus: a challenging fetal diagnosis. Ultrasound Obstet Gynecol 2021; 57:500-501. [PMID: 32250490 DOI: 10.1002/uog.22039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/20/2020] [Accepted: 03/27/2020] [Indexed: 06/11/2023]
Affiliation(s)
- Y Wen
- Department of Ultrasound, The Fifth People's Hospital of Chengdu, Chengdu, Sichuan Province, China
| | - G Xiang
- Department of Ultrasound, The Fifth People's Hospital of Chengdu, Chengdu, Sichuan Province, China
| | - C Xiong
- Department of Ultrasound, The Fifth People's Hospital of Chengdu, Chengdu, Sichuan Province, China
| | - Y Yang
- Department of Radiology, The Women and Children's Hospital of Chengdu, Chengdu, Sichuan Province, China
| | - J Zhang
- Department of Ultrasound, The Fifth People's Hospital of Chengdu, Chengdu, Sichuan Province, China
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Xiong C, Kaczmarek K, Zabrocki J, Nachman RJ, Pietrantonio PV. Activity of native tick kinins and peptidomimetics on the cognate target G protein-coupled receptor from the cattle fever tick, Rhipicephalus microplus (Acari: Ixodidae). Pest Manag Sci 2020; 76:3423-3431. [PMID: 31794138 DOI: 10.1002/ps.5704] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 11/13/2019] [Accepted: 11/28/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Kinins are multifunctional neuropeptides that regulate key insect physiological processes such as diuresis, feeding, and ecdysis. However, the physiological roles of kinins in ticks are unclear. Furthermore, ticks have an expanded number of kinin paracopies in the kinin gene. Silencing the kinin receptor (KR) in females of Rhipicephalus microplus reduces reproductive fitness. Thus, it appears the kinin signaling system is important for tick physiology and its disruption may have potential for tick control. RESULTS We determined the activities of endogenous kinins on the KR, a G protein-coupled receptor, and identified potent peptidomimetics. Fourteen predicted R. microplus kinins (Rhimi-K), and 11 kinin analogs containing aminoisobutyric acid (Aib) were tested. The latter incorporated tick kinin sequences and/or were modified for enhanced resistance to arthropod peptidases. A high-throughput screen using a calcium fluorescence assay in 384-well plates was performed. All tested kinins and Aib analogs were full agonists. The most potent kinin and two kinin analogs were equipotent. Analogs 2414 ([Aib]FS[Aib]WGa) and 2412 ([Aib]FG[Aib]WGa) were the most active with EC50 values of 0.9 and 1.1 nM, respectively, matching the EC50 of the most potent tick kinin, Rhimi-K-14 (QDSFNPWGa) (EC50 = 1 nM). The potent analog 2415 ([Aib]FR[Aib]WGa, EC50 = 6.8 nM) includes both Aib molecules for resistance to peptidases and a positively charged residue, R, for enhanced water solubility and amphiphilic character. CONCLUSION These tick kinins and pseudopeptides expand the repertoire of reagents for tick physiology and toxicology towards finding novel targets for tick management. © 2019 Society of Chemical Industry.
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Affiliation(s)
- Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX, USA
| | - Krzysztof Kaczmarek
- Institute of Organic Chemistry, Lodz University of Technology, Lodz, Poland
- Insect Neuropeptide Lab, Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, College Station, TX, USA
| | - Janusz Zabrocki
- Institute of Organic Chemistry, Lodz University of Technology, Lodz, Poland
- Insect Neuropeptide Lab, Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, College Station, TX, USA
| | - Ronald J Nachman
- Insect Neuropeptide Lab, Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, College Station, TX, USA
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Silbernagel KM, Jechorek RP, Carver CN, Horter BL, Lindberg KG, Aleo V, Anderson G, Bannach B, Bulthaus M, Cha K, Dixon K, Hemming B, Horter B, Iannucci; M, Johnson A, Johnson K, Kaufer A, Kemp S, King J, Kupski B, Kusch S, Luebbert B, Lyke H, Makepeace; C, Otten N, Schomogy T, Strand S, Xiong C. 3M™ Petrifilm™ Staph Express Count Plate Method for the Enumeration of Staphylococcus aureus in Selected Dairy Foods: Collaborative Study. J AOAC Int 2019. [DOI: 10.1093/jaoac/86.5.963] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The 3M™ Petrifilm™ Staph Express Count plate method was compared with AOAC Official Method 975.55 for the enumeration of Staphylococcus aureus in selected foods. Five foods—ice cream, raw milk, yogurt, whey powder, and cheese—were analyzed for S. aureus by 12 collaborating laboratories. For each food tested, the collaborators received 8 blind test samples consisting of a control sample, a low inoculation level, a medium inoculation level, and a medium inoculation level with background flora, each in duplicate. The mean log10 counts for the methods were comparable for all 5 foods. The repeatability and reproducibility variances of the 24 h Petrifilm Staph Express Count plate method were similar to those of the 72 h standard method.
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Xiong C. The impact of newly diagnosed diabetes mellitus on cancer-free survival in patients without colorectal polyps: A secondary analysis of Korean multicenter cancer cohort. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz421.008] [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: 11/14/2022] Open
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Liu B, Wu W, Liu Z, Wang H, He J, Xiong C. P4363The predictive capacity of two- and three-dimensional echocardiography detected right ventricular strain in disease severity of pre-capillary pulmonary hypertension. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0768] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Pulmonary hypertension (PH) patients have poor prognosis due to progressive right ventricular (RV) dysfunction. As a low-cost and non-invasive tool, echocardiography is by far the most widely used technique to investigate the RV structure and function in PH patients. Recent studies showed that RV longitudinal strain (RVLS) measured by two- or three-dimensional echocardiography (2DE, 3DE) was correlated with RV function parameters and have the potential to predict the prognosis of PH patients. However, few studies have compared the value of 2DE- and 3DE- RVLS to predict disease severity of pre-capillary PH patients. Therefore, our study aims to compare the capacity of RVLS assessed by 3DE and 2DE in predicting disease severity of pre-capillary PH patients.
Methods
We consecutively enrolled 57 patients (18 males and 39 females, 35±13 years) with pre-capillary PH diagnosed by right heart catheterization in our center. Standard transthoracic echocardiography was performed in all participants. 2DE- RVLS were obtained from speckle-tracking analyses using GE EchoPAC version 201; while 3DE- RVLS were analyzed by TomTec 4D RV-Function 2.0. On the basis of the risk assessment strategy of 2015 ESC Guidelines for the diagnosis and treatment of pulmonary hypertension, all the participants were classified into low risk or intermediate-high risk groups. Linear regression analyses were performed to evaluate the correlations between RVLS and peak oxygen consumption (PVO2). In addition, receive operating characteristic curves (ROC) were used to compare the predictive values of 2DE- and 3DE-RVLS and identify the optimal cut points for the detection of low risk based on the risk assessment strategy of 2015 ESC Guidelines.
Results
Linear regression analyses showed a significant correlation between PVO2 and 2DE- RVLS (r=−0.484, P<0.001), while a relatively weaker correlation was observed between PVO2 and 3DE- RVLS (r=−0.299, P=0.024). ROC curve showed 2DE-RVEF had a better capacity to classify pre-capillary PH patients into low or intermediate-high risk groups (2DE- vs 3DE-: AUC=0.78, P=0.003 vs AUC=0.69, P=0.044). Optimal cut-offs found 2DE-RVEF <−13.85% had a 73.3% sensibility and 75.0% specificity to predict low risk.
Conclusions
Both two- and three-dimensional echocardiography detected RVLS had the potential to evaluate disease severity of pre-capillary PH patients, but the former may have a better predictive capacity.
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Affiliation(s)
- B Liu
- Fuwai Hospital- Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - W Wu
- Fuwai Hospital- Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Z Liu
- Fuwai Hospital- Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - H Wang
- Fuwai Hospital- Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - J He
- Fuwai Hospital- Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - C Xiong
- Fuwai Hospital- Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Xiong C, Baker D, Pietrantonio PV. The Cattle Fever Tick, Rhipicephalus microplus, as a Model for Forward Pharmacology to Elucidate Kinin GPCR Function in the Acari. Front Physiol 2019; 10:1008. [PMID: 31447698 PMCID: PMC6692460 DOI: 10.3389/fphys.2019.01008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 07/22/2019] [Indexed: 12/12/2022] Open
Abstract
The success of the acaricide amitraz, a ligand of the tick tyramine/octopamine receptor (a G protein-coupled receptor; GPCR), stimulated interest on arthropod-specific GPCRs as targets to control tick populations. This search advances tick physiology because little is known about the pharmacology of tick GPCRs, their endogenous ligands or their physiological functions. Here we explored the tick kinin receptor, a neuropeptide GPCR, and its ligands. Kinins are pleiotropic insect neuropeptides but their function in ticks is unknown. The endogenous tick kinins are unknown and their cDNAs have not been cloned in any species. In contrast, more than 271 insect kinin sequences are available in the DINeR database. To fill this gap, we cloned the kinin cDNA from the cattle fever tick, Rhipicephalus microplus, which encodes 17 predicted kinins, and verified the kinin gene structure. We predicted the kinin precursor sequences from additional seven tick species, including Ixodes scapularis. All species showed an expansion of kinin paracopies. The "kinin core" (minimal active sequence) of tick kinins FX1X2WGamide is similar to those in insects. Pro was predominant at the X2 position in tick kinins. Toward accelerating the discovery of kinin function in ticks we searched for novel synthetic receptor ligands. We developed a dual-addition assay for functional screens of small molecules and/or peptidomimetics that uses a fluorescent calcium reporter. A commercial library of fourteen small molecules antagonists of mammalian neurokinin (NK) receptors was screened using this endpoint assay. One acted as full antagonist (TKSM02) with inhibitory concentration fifty (IC50) of ∼45 μM, and three were partial antagonists. A subsequent calcium bioluminescence assay tested these four antagonists through kinetic curves and confirmed TKSM02 as full antagonist and one as partial antagonist (TKSM14). Antagonists of NK receptors displayed selectivity (>10,000-fold) on the tick kinin receptor. Three peptidomimetic ligands of the mammalian NK receptors (hemokinin 1, antagonist G, and spantide I) were tested in the bioluminescence assay but none were active. Forward approaches may accelerate discovery of kinin ligands, either as reagents for tick physiological research or as lead molecules for acaricide development, and they demonstrate that selectivity is achievable between mammalian and tick neuropeptide systems.
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Affiliation(s)
- Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX, United States
| | - Dwight Baker
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, United States
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Xiong C, Kaczmarek K, Zabrocki J, Pietrantonio PV, Nachman RJ. Evaluation of Aib and PEG-polymer insect kinin analogs on mosquito and tick GPCRs identifies potent new pest management tools with potentially enhanced biostability and bioavailability. Gen Comp Endocrinol 2019; 278:58-67. [PMID: 30107140 DOI: 10.1016/j.ygcen.2018.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 07/02/2018] [Accepted: 08/01/2018] [Indexed: 11/22/2022]
Abstract
Insect kinins modulate aspects of diuresis, digestion, development, and sugar taste perception in tarsi and labellar sensilla in mosquitoes. They are, however, subject to rapid biological degradation by endogenous invertebrate peptidases. A series of α-aminoisobutyric (Aib) acid-containing insect kinin analogs incorporating sequences native to the Aedes aegypti mosquito aedeskinins were evaluated on two recombinant kinin invertebrate receptors stably expressed in cell lines, discovering a number of highly potent and biostable insect kinin mimics. On the Ae. aegypti mosquito kinin receptor, three highly potent, biostable Aib analogs matched the activity of the Aib-containing biostable insect kinin analog 1728, which previously showed disruptive and/or aversive activity in aphid, mosquito and kissing bug. These three analogs are IK-Aib-19 ([Aib]FY[Aib]WGa, EC50 = 18 nM), IK-Aib-12 (pQKFY[Aib]WGa, EC50 = 23 nM) and IK-Aib-20 ([Aib]FH[Aib]WGa, EC50 = 28 nM). On the Rhipicephalus (Boophilus) microplus tick receptor, IK-Aib-20 ([Aib]FH[Aib]WGa, EC50 = 2 nM) is more potent than 1728 by a factor of 3. Seven other potentially biostable analogs exhibited an EC50 range of 5-10 nM, all of which match the potency of 1728. Among the multi-Aib hexapeptide kinin analogs tested the tick receptor has a preference for the positively-charged, aromatic H over the aromatic residues Y and F in the X1 variable position ([Aib]FX1[Aib]WGa), whereas the mosquito receptor does not distinguish between them. In contrast, in a mono-Aib pentapeptide analog framework (FX1[Aib]WGa), both receptors exhibit a preference for Y over H in the variable position. Among analogs incorporating polyethylene glycol (PEG) polymer attachments at the N-terminus that can confer enhanced bioavailability and biostability, three matched or surpassed the potency of a positive control peptide. On the tick receptor IK-PEG-9 (P8-R[Aib]FF[Aib]WGa) was the most potent. Two others, IK-PEG-8 (P8-RFFPWGa) and IK-PEG-6 (P4-RFFPWGa), were most potent on the mosquito receptor, with the first surpassing the activity of the positive control peptide. These analogs and others in the IK-Aib series expand the toolbox of potent analogs accessible to invertebrate endocrinologists studying the structural requirements for bioactivity and the as yet unknown role of the insect kinins in ticks. They may contribute to the development of selective, environmentally friendly pest arthropod control agents.
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Affiliation(s)
- Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX 77843, USA
| | - Krzysztof Kaczmarek
- Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, 2881 F/B Road, College Station, TX 77845, USA; Institute of Organic Chemistry, Lodz University of Technology, 90-924 Lodz, Poland
| | - Janusz Zabrocki
- Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, 2881 F/B Road, College Station, TX 77845, USA; Institute of Organic Chemistry, Lodz University of Technology, 90-924 Lodz, Poland
| | | | - Ronald J Nachman
- Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, 2881 F/B Road, College Station, TX 77845, USA.
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Xiao W, Gong C, Liu X, Liu Y, Peng S, Luo D, Wang R, Li T, Zhao J, Xiong C, Liang S, Xu H. Association of P2X7R gene with serum lipid profiles in Chinese postmenopausal women with osteoporosis. Climacteric 2019; 22:498-506. [DOI: 10.1080/13697137.2019.1604654] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- W. Xiao
- Department of Pathology, Jiangxi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - C. Gong
- Department of Science and Education, Chest Hospital of Jiangxi Province, Nanchang, Jiangxi, China
| | - X. Liu
- Clinical Medical College, JiangXi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - Y. Liu
- Department of Physiology, JiangXi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - S. Peng
- Basic Medical College, JiangXi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - D. Luo
- Basic Medical College, JiangXi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - R. Wang
- Department of Physiology, JiangXi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - T. Li
- Clinical Medical College, JiangXi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - J. Zhao
- Clinical Medical College, JiangXi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - C. Xiong
- Department of Nursing, The Second Affliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - S. Liang
- Department of Physiology, JiangXi Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - H. Xu
- Department of Physiology, JiangXi Medical College of Nanchang University, Nanchang, Jiangxi, China
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Xiong C, Zhao T, Ren Y, Jiang H, Zhou X. Mathematical modeling of the charging process of Li-S batteries by incorporating the size-dependent Li2S dissolution. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2018.11.159] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Chen S, Meng Y, Shen Y, Ning X, Xiong C, Lin Z, Zheng Q, Zheng Z, Yin P, Huang H, Yao M. Chemotherapy May Not be Necessary in Stage II Nasopharyngeal Carcinoma Treated with Intensity-Modulated Radiation Therapy. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.06.313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Pietrantonio PV, Xiong C, Nachman RJ, Shen Y. G protein-coupled receptors in arthropod vectors: omics and pharmacological approaches to elucidate ligand-receptor interactions and novel organismal functions. Curr Opin Insect Sci 2018; 29:12-20. [PMID: 30551818 PMCID: PMC6296246 DOI: 10.1016/j.cois.2018.05.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/21/2018] [Accepted: 05/23/2018] [Indexed: 05/04/2023]
Abstract
Regulation of many physiological processes in animals, certainly those controlled by neuropeptide hormones, involves G protein-coupled receptors (GPCRs). Our work focusing on endocrine regulation of diuresis and water balance in mosquitoes and ticks started in 1997 with the kinin receptor, at the dawn of the omics era. After the genomic revolution, we began work on the endocrinology of reproduction in the red imported fire ant. We will use the template of this comparative work to summarize key points about GPCRs and signaling, and emphasize the most recent developments in the pharmacology of arthropod neuropeptide GPCRs. We will discuss omics' contributions to the advancement of this field, and its influence on peptidomimetic design while emphasizing work on blood feeding arthropods.
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Affiliation(s)
- Patricia V Pietrantonio
- Department of Entomology, Texas A&M University (TAMU), College Station, TX 77843-2475, United States.
| | - Caixing Xiong
- Department of Entomology, TAMU, College Station, TX 77843-2475, United States
| | - Ronald James Nachman
- Southern Plains Agricultural Research Center, USDA-ARS, College Station, TX 77845, United States
| | - Yang Shen
- Department of Electrical and Computer Engineering, TAMU, College Station, TX 77843-3128, United States
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24
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Luo J, Weng H, Morris JC, Xiong C. Minimizing the Sample Sizes of Clinical Trials on Preclinical and Early Symptomatic Stage of Alzheimer Disease. J Prev Alzheimers Dis 2018; 5:110-119. [PMID: 29616704 DOI: 10.14283/jpad.2018.16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Clinical trials of investigational drugs for Alzheimer disease (AD) increasingly focus on the prodromal (symptomatic) stage of the illness and now its preclinical (asymptomatic) stage. Sensitive and specific cognitive and functional endpoints are needed to track subtle cognitive and functional changes in the early and preclinical stages to minimize sample sizes in these trials. OBJECTIVES To identify informative items in a standard clinical assessment protocol and a psychometric battery that are predictive of onset of dementia symptom. DESIGN Longitudinal retrospective study. SETTING Washington University (WU) Knight Alzheimer Disease Research Center (ADRC). PARTICIPANTS A total of 735 individuals at least 65 years old and cognitively normal at baseline from a longitudinal clinical cohort at the WU Knight ADRC. MEASUREMENTS The annual clinical assessment included a wide spectrum of functional and cognitive domains; a comprehensive psychometric battery was completed about 2 weeks after the clinical evaluation. Psychometricians are blinded to the results of the clinical evaluation and to the prior performance of the participants on the psychometric tests. RESULTS The mean age at baseline of the 735 participants was 74.30 and 62.31% were female. 240 individuals developed prodromal dementia symptoms (consistent with mild cognitive impairment due to AD and with very mild AD dementia) during longitudinal follow-up (mean follow-up=6.79 years). Among a total of 562 items in the clinical and cognitive assessments under analysis, 292 (52%) were identified as informative because their longitudinal changes were predictive of symptomatic onset. When these items were used to form the functional and cognitive composites, the longitudinal rates of changes were free of a learning effect and captured subtle longitudinal progression prior to symptomatic onset. The rates of change were much greater right after the symptomatic onset than those from the functional and cognitive composites formed using non-informative items. Although the sample sizes for prevention trials (prior to symptomatic onset) using the informative items still yield large numbers, the sample sizes for early treatment trial (after symptomatic onset) was much smaller than those derived from all the items or from the non-informative items alone. CONCLUSIONS The antecedent longitudinal changes in nearly half of the items in a clinical assessment protocol and a comprehensive cognitive battery did not show statistically significant ability to predict the dementia symptom onset, and hence may be non-informative to track the preclinical functional and cognitive progression of AD. The remaining items, on the other hand, captured some of the preclinical changes prior to the symptom onset, but performed much better right after the symptom onset. Currently ongoing prevention trials on preclinical AD of elderly individuals may need to re-assess the sample sizes and statistical power.
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Affiliation(s)
- J Luo
- Chengjie Xiong, Division of Biostatistics, Campus Box 8067, 4523 Clayton Ave., St. Louis, MO, 63110-1093, Phone: 314-362-3635; Fax: 314-362-2693,
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Xiong C, Zhang X. [Progress of clinical correlation research on migraine and glaucoma]. Zhonghua Yan Ke Za Zhi 2018. [PMID: 29518882 DOI: 10.3760/cma.j.issn.0412-4081.2018.03.015] [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] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Migraine is a common primary headache disorder. The estimated annual prevalence rate of migraine in China is 9.3%. Migraine is typically involved with a series of ocular symptoms including glaucoma, visual performance tests relevant to glaucoma exhibited correlation between glaucoma and migraine. Even though migraine patients exhibit no glaucoma-related signs during intermissions of migraine attacks, the results of visual function tests (visual field, electrophysiology, ocular imaging) relevant to glaucoma still indicate abnormalities. It is fairly typical that most of the patients may neglect their ocular problems when migraine breaks out. Epidemiological data suggests an increasing prevalence of migraine patients with glaucoma, particularly normal tension glaucoma. This paper reviews and discusses the effect of migraine on the clinical assessment and diagnosis of glaucoma. (Chin J Ophthalmol, 2018, 54: 224-228).
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Affiliation(s)
- C Xiong
- Affiliated Eye Hospital of Nanchang University, Jiangxi Research Institute of Ophthalmology & Visual Sciences, Jiangxi Provincial Key Laboratory for Ophthalmology, Nanchang 330006, China
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26
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Zhang X, Lee YH, Bell BA, Leong PHW, Rudolph T, Eggleton BJ, Xiong C. Indistinguishable heralded single photon generation via relative temporal multiplexing of two sources. Opt Express 2017; 25:26067-26075. [PMID: 29041268 DOI: 10.1364/oe.25.026067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 10/04/2017] [Indexed: 06/07/2023]
Abstract
Generating N single photons simultaneously is a formidable challenge due to the lack of deterministic single photon sources. Recent work [New J. Phys. 19, 063013 (2017] has proposed a relative multiplexing scheme that can enhance the N single photons probability with a minimum of active switching resources. We experimentally demonstrate relative temporal multiplexing on two photon sources with a 90% additional enhancement over the standard temporal multiplexing scheme demonstrated previously. 88 ± 11% visibility of Hong-Ou-Mandel quantum interference verifies the indistinguishability of the heralded single photons after the synchronization. This proof-of-principle demonstration points out the potential significance of the relative multiplexing scheme for large-scale photonic quantum information processing.
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Gill DM, Xiong C, Rosenberg JC, Pepeljugoski P, Orcutt JS, Green WMJ. Modulator figure of merit for short reach data links. Opt Express 2017; 25:24326-24339. [PMID: 29041377 DOI: 10.1364/oe.25.024326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 09/15/2017] [Indexed: 06/07/2023]
Abstract
The traditional Mach-Zehnder modulator (MZM) figure of merit (FOM) has been defined as (Vπ2)/υ3dBe, and works effectively for LiNbO3 long haul modulators. However, for plasma dispersion based electro-optic modulators, or any modulator that has an inherent relationship between its bandwidth, required drive voltage, and optical insertion loss/gain, this FOM is inappropriate. This is particularly true for short reach links with no optical amplification. In the following, we propose a new modulator FOM (M-FOM) based on device metrics that are essential for short-reach links, such as the peak-to-peak drive voltage, modulator rise-fall time, and relative optical modulation amplitude. Link sensitivity measurements from two MZMs that have different bandwidths and optical losses are compared using our M-FOM to demonstrate its utility. Furthermore, we present a novel application protocol of our M-FOM to provide deeper insight into the relative system impact that modulator performance has on data links with no optical amplification, by taking the ratio of M-FOMs from two modulators driven with the same radio frequency drive power.
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Liu F, Xiong C, Liu N. Chemoreception to aggregation pheromones in the common bed bug, Cimex lectularius. Insect Biochem Mol Biol 2017; 82:62-73. [PMID: 28167332 DOI: 10.1016/j.ibmb.2017.01.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 01/30/2017] [Accepted: 01/31/2017] [Indexed: 06/06/2023]
Abstract
The common bed bug, Cimex lectularius, is an obligate blood-feeding insect that is resurgent worldwide, posing a threat to human beings through its biting nuisance and disease transmission. Bed bug aggregation pheromone is considered a very promising attractant for use in the monitoring and management of bed bugs, but as yet little is known regarding the sensory physiology of bed bugs related to this pheromone. This study examined how the individual components of aggregation pheromone are perceived by the olfactory receptor neurons (ORNs) housed in different types of olfactory sensilla in bed bugs and the molecular basis for the ORNs' responses to the aggregation pheromone. We found that the ORNs in the D olfactory sensilla played a predominant role in detecting all the components of aggregation pheromone except for histamine, which was only recognized by the C sensilla. Bed bugs' E sensilla, which include four functionally distinct groups, showed only a very weak but variant sensitivity (both excitatory and inhibitory) to the components of aggregation pheromone. Functional tests of 15 odorant receptors (ORs) in response to the components of aggregation pheromone revealed that most of these components were encoded by multiple ORs with various tuning properties. This study provides a comprehensive understanding of how bed bug aggregation pheromone is perceived and recognized in the peripheral olfactory system and will contribute useful information to support the development of synthetic attractants for bed bug monitoring and control.
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Affiliation(s)
- Feng Liu
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, USA
| | - Caixing Xiong
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, USA
| | - Nannan Liu
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, USA.
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29
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Gill DM, Green WMJ, Xiong C, Rylyakov A, Schow C, Proesel J, Rosenberg JC, Barwicz T, Khater M, Assefa S, Shank SM, Reinholm C, Kiewra E, Kamlapurkar S, Vlasov YA. Distributed electrode Mach-Zehnder modulator with double-pass phase shifters and integrated inductors. Opt Express 2015; 23:16857-16865. [PMID: 26191697 DOI: 10.1364/oe.23.016857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A novel high-speed Mach-Zehnder modulator (MZM) fully integrated into a 90 nm CMOS process is presented. The MZM features 'double-pass' optical phase shifter segments, and the first use of integrated inductors in a 'velocity-matched' distributed-electrode configuration.
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Zhang X, Jizan I, He J, Clark AS, Choi DY, Chae CJ, Eggleton BJ, Xiong C. Enhancing the heralded single-photon rate from a silicon nanowire by time and wavelength division multiplexing pump pulses. Opt Lett 2015; 40:2489-2492. [PMID: 26030539 DOI: 10.1364/ol.40.002489] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Heralded single photons produced on a silicon chip represent an integrated photon source solution for scalable photonic quantum technologies. The key limitation of such sources is their non-deterministic nature introduced by the stochastic spontaneous four-wave mixing (SFWM) process. Active spatial and temporal multiplexing can improve this by enhancing the single-photon rate without degrading the quantum signal-to-noise ratio. Here, taking advantage of the broad bandwidth of SFWM in a silicon nanowire, we experimentally demonstrate heralded single-photon generation from a silicon nanowire pumped by time and wavelength division multiplexed pulses. We show a 90±5% enhancement on the heralded photon rate at the cost of only 14±2% reduction to the signal-to-noise ratio, close to the performance found using only time division multiplexed pulses. As single-photon events are distributed to multiple wavelength channels, this new scheme overcomes the saturation limit of avalanche single-photon detectors and will improve the ultimate performance of such photon sources.
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31
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Cai Y, Liu T, Fang F, Shen S, Xiong C. Involvement of ICAM-1 in impaired spermatogenesis after busulfan treatment in mice. Andrologia 2015; 48:37-44. [DOI: 10.1111/and.12414] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/05/2015] [Indexed: 01/14/2023] Open
Affiliation(s)
- Y. Cai
- Family Planning Research Institute; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
| | - T. Liu
- Department of Thoracic Surgery; Renmin Hospital of Wuhan University; Wuhan China
| | - F. Fang
- Family Planning Research Institute; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
| | - S. Shen
- Zhong Shen Bioscience Inc.; Wuhan China
| | - C. Xiong
- Family Planning Research Institute; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
- Center for Reproductive Medicine; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
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Abner EL, Schmitt FA, Nelson PT, Lou W, Wan L, Gauriglia R, Dodge HH, Woltjer RL, Yu L, Bennett DA, Schneider JA, Chen R, Masaki K, Katz MJ, Lipton RB, Dickson DW, Lim KO, Hemmy LS, Cairns NJ, Grant E, Tyas SL, Xiong C, Fardo DW, Kryscio RJ. The Statistical Modeling of Aging and Risk of Transition Project: Data Collection and Harmonization Across 11 Longitudinal Cohort Studies of Aging, Cognition, and Dementia. Obs Stud 2015; 1:56-73. [PMID: 25984574 PMCID: PMC4431579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Longitudinal cognitive trajectories and other factors associated with mixed neuropathologies (such as Alzheimer's disease with co-occurring cerebrovascular disease) remain incompletely understood, despite being the rule and not the exception in older populations. The Statistical Modeling of Aging and Risk of Transition study (SMART) is a consortium of 11 different high-quality longitudinal studies of aging and cognition (N=11,541 participants) established for the purpose of characterizing risk and protective factors associated with subtypes of age-associated mixed neuropathologies (N=3,001 autopsies). While brain donation was not required for participation in all SMART cohorts, most achieved substantial autopsy rates (i.e., > 50%). Moreover, the studies comprising SMART have large numbers of participants who were followed from intact cognition and transitioned to cognitive impairment and dementia, as well as participants who remained cognitively intact until death. These data provide an exciting opportunity to apply sophisticated statistical methods, like Markov processes, that require large, well-characterized samples. Thus, SMART will serve as an important resource for the field of mixed dementia epidemiology and neuropathology.
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Affiliation(s)
- E L Abner
- Snders-Brown Center on Aging, University of Kentucky
| | - F A Schmitt
- Oregon Center for Aging & Technology, Oregon Health & Science University
| | - P T Nelson
- Rush Alzheimer's Disease Center, Rush University Medical Center
| | | | - L Wan
- Department of Neurology, Albert Einstein College of Medicine
| | - R Gauriglia
- Department of Laboratory Medicine & Pathology, Mayo Clinic Jacksonville
| | - H H Dodge
- Department of Psychiatry, University of Minnesota
| | - R L Woltjer
- Alzheimer's Disease Research Center, Washington University
| | - L Yu
- School of Public Health and Health Systems, University of Waterloo
| | - D A Bennett
- College of Public Health, University of Kentucky
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Ponce DP, Salech F, Martin C, Silva M, Xiong C, Roe C, Henriquez M, Quest F, Behrens I. Increased Susceptibility to Oxidative Death of Lymphocytes from Alzheimer Patients Correlates with Dementia Severity. Curr Alzheimer Res 2014. [DOI: 10.2174/1567205011666141001113135] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Affiliation(s)
- R. R. Sagar
- Key Laboratory of Advanced Materials (MOE)School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
- Beijing National Center for Electron MicroscopyBeijing 100084, China
| | - X. Zhang
- Key Laboratory of Advanced Materials (MOE)School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
- Beijing National Center for Electron MicroscopyBeijing 100084, China
| | - C. Xiong
- Key Laboratory of Advanced Materials (MOE)School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
- Beijing National Center for Electron MicroscopyBeijing 100084, China
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Zhang Z, Xiong C, Jiang QW. Survey on rabies virus carried by domestic dogs in Henan and Shaanxi Province, China. Int J Infect Dis 2014. [DOI: 10.1016/j.ijid.2014.03.809] [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: 11/29/2022] Open
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36
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Cai Y, Liu T, Li H, Xiong C. Meta-analysis of the association of oestrogen receptor-beta gene RsaI (G/A) and AluI (A/G) polymorphisms with male infertility. Andrologia 2014; 47:257-65. [PMID: 24655068 DOI: 10.1111/and.12254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/05/2014] [Indexed: 11/27/2022] Open
Abstract
A more precise assessment of association of oestrogen receptor-beta genes RsaI(G/A) and AluI(A/G) polymorphisms with male infertility from current contradictory results is the aim of this meta-analysis including five RsaI and six AluI studies respectively. No association was observed between infertility and RsaI or AluI. In the stratified analysis by ethnicity, increased risk was found among Caucasians with GA versus GG (OR = 2.263, 95% CI = 1.073-4.776, I(2) = 57.1%) and dominant model (OR = 2.117, 95% CI = 1.018-4.403, I(2) = 49.0%) of RsaI. It was not observed for AluI. In the stratified analysis by infertility subtypes, a reduced risk in GA of AluI was observed among azoospermia or severe oligospermia (GA versus AA: OR = 0.686, 95% CI = 0.498-0.945, I(2) = 21.2%; recessive model: OR = 1.403, 95% CI = 1.056-1.864, I(2) = 31.7%), and reduced risk was in recessive model (OR = 0.650, 95% CI = 0.446-0.948, I(2) = 0.0%) of subtypes, except for azoospermia or severe oligospermia. However, this finding was not observed in RsaI. The meta-analysis showed GA and GG of AluI are possibly resistant factors for spermatogenesis dysfunction and deteriorated sperm quality.
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Affiliation(s)
- Y Cai
- Family Planning Research Institute, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Xiong C, Vo TD, Collins MJ, Li J, Krauss TF, Steel MJ, Clark AS, Eggleton BJ. Bidirectional multiplexing of heralded single photons from a silicon chip. Opt Lett 2013; 38:5176-5179. [PMID: 24281539 DOI: 10.1364/ol.38.005176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We demonstrate integrated spatial multiplexing of heralded single photons generated from a single 96 μm long silicon photonic crystal waveguide in a bidirectional pump configuration. By using a low-loss fiber-coupled opto-ceramic switch, the multiplexing technique enhances the brightness of the single photon source by 51.2±4.0% while maintaining the coincidence-to-accidental ratio. Compared with the demonstration of multiplexing two individual sources, the bidirectional pump scheme represents a twofold reduction in the footprint of nonlinear devices for future large-scale integration of on-chip single photon sources. The 51.2±4.0% gain will make any quantum operation requiring n photons 1.5(n) times faster.
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Mills SM, Mallmann J, Santacruz AM, Fuqua A, Carril M, Aisen PS, Althage MC, Belyew S, Benzinger TL, Brooks WS, Buckles VD, Cairns NJ, Clifford D, Danek A, Fagan AM, Farlow M, Fox N, Ghetti B, Goate AM, Heinrichs D, Hornbeck R, Jack C, Jucker M, Klunk WE, Marcus DS, Martins RN, Masters CM, Mayeux R, McDade E, Morris JC, Oliver A, Ringman JM, Rossor MN, Salloway S, Schofield PR, Snider J, Snyder P, Sperling RA, Stewart C, Thomas RG, Xiong C, Bateman RJ. Preclinical trials in autosomal dominant AD: implementation of the DIAN-TU trial. Rev Neurol (Paris) 2013; 169:737-43. [PMID: 24016464 DOI: 10.1016/j.neurol.2013.07.017] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [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: 07/15/2013] [Accepted: 07/19/2013] [Indexed: 10/26/2022]
Abstract
The Dominantly Inherited Alzheimer's Network Trials Unit (DIAN-TU) was formed to direct the design and management of interventional therapeutic trials of international DIAN and autosomal dominant Alzheimer's disease (ADAD) participants. The goal of the DIAN-TU is to implement safe trials that have the highest likelihood of success while advancing scientific understanding of these diseases and clinical effects of proposed therapies. The DIAN-TU has launched a trial design that leverages the existing infrastructure of the ongoing DIAN observational study, takes advantage of a variety of drug targets, incorporates the latest results of biomarker and cognitive data collected during the observational study, and implements biomarkers measuring Alzheimer's disease (AD) biological processes to improve the efficiency of trial design. The DIAN-TU trial design is unique due to the sophisticated design of multiple drugs, multiple pharmaceutical partners, academics servings as sponsor, geographic distribution of a rare population and intensive safety and biomarker assessments. The implementation of the operational aspects such as home health research delivery, safety magnetic resonance imagings (MRIs) at remote locations, monitoring clinical and cognitive measures, and regulatory management involving multiple pharmaceutical sponsors of the complex DIAN-TU trial are described.
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Affiliation(s)
- S M Mills
- DIAN-TU, Washington University, 660, S. Euclid Avenue, Campus Box 8111, St. Louis, MO 63108, USA
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40
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Collins M, Xiong C, Rey I, Vo T, He J, Shahnia S, Reardon C, Krauss T, Steel M, Clark A, Eggleton B. Integrated spatial multiplexing of heralded single-photon sources. Nat Commun 2013; 4:2582. [PMID: 24107840 PMCID: PMC3826656 DOI: 10.1038/ncomms3582] [Citation(s) in RCA: 193] [Impact Index Per Article: 17.5] [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: 05/28/2013] [Accepted: 09/10/2013] [Indexed: 11/09/2022] Open
Abstract
The non-deterministic nature of photon sources is a key limitation for single-photon quantum processors. Spatial multiplexing overcomes this by enhancing the heralded single-photon yield without enhancing the output noise. Here the intrinsic statistical limit of an individual source is surpassed by spatially multiplexing two monolithic silicon-based correlated photon pair sources in the telecommunications band, demonstrating a 62.4% increase in the heralded single-photon output without an increase in unwanted multipair generation. We further demonstrate the scalability of this scheme by multiplexing photons generated in two waveguides pumped via an integrated coupler with a 63.1% increase in the heralded photon rate. This demonstration paves the way for a scalable architecture for multiplexing many photon sources in a compact integrated platform and achieving efficient two-photon interference, required at the core of optical quantum computing and quantum communication protocols.
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Affiliation(s)
- M.J. Collins
- Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - C. Xiong
- Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - I.H. Rey
- SUPA, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS, UK
| | - T.D. Vo
- Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
- Maritime Division, Department of Defence, Defence Science and Technology Organisation (DSTO), P.O. Box 44, Pyrmont, New South Wales 2009, Australia
| | - J. He
- Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - S. Shahnia
- Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - C. Reardon
- Department of Physics, University of York, York YO10 5DD, UK
| | - T.F. Krauss
- SUPA, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS, UK
- Department of Physics, University of York, York YO10 5DD, UK
| | - M.J. Steel
- Department of Physics and Astronomy, CUDOS, MQ Photonics Research Centre, Macquarie University, New South Wales 2019, Australia
| | - A.S. Clark
- Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - B.J. Eggleton
- Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
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Cheng D, Xiong C, Li J, Sui C, Wang S, Li H, Jiang X. The effect of mahogunin gene mutant on reproduction in male mice: a new sight for infertility? Andrologia 2012; 46:98-105. [PMID: 23210986 DOI: 10.1111/and.12050] [Citation(s) in RCA: 6] [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] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/04/2012] [Indexed: 01/29/2023] Open
Abstract
Mahogunin is an important mediator of chromogenesis and neurodegeneration. Mahoganoid is a mutation of the mahogunin gene, which causes a pleiotropic phenotype that includes suppression of obesity, spongiform neurodegeneration and improvement of insulin sensitivity. Our previous research found that mahoganoid widely expressed in the male rat reproductive system, and mahoganoid-deficient mice have reduced embryonic viability. But the reproductive change in mahogunin knockout (md(nc) ) male mice has not been reported previously. Here, we report that the mahogunin mRNA also widely exists in reproductive system of male mice, and its mRNA expression in the testis was in accordance with the first spermatogenesis wave cycle. Moreover, we find that md(nc) male mice were able to mate with females but no pups are delivered. Besides, the sperms' active progressive motility and hormone secretion (E2, FSH, LH, PRL) were obviously decreased while abnormal sperm rate showed no significant difference in md(nc) compared to wild-type (WT) male mice. This study indicates the mahogunin deficiency results in the infertility of male mice, disruption of hormones secretion and impaired active progressive motility, which may additionally illuminate the aetiology of male infertility in human.
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Affiliation(s)
- D Cheng
- Family Planning Research Institute, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Reproductive medical center, Renmin hospital of WuHan University, Wuhan, China
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Lu J, Zou L, Xiong C, Wang Z, Ma H, Yang W, Cui T, Zhang L, Huang S, Sun Q, Gao J, Meng Q. Development of a time-resolved fluoroimmunoassay of CFP-10 for rapid diagnosis of tuberculous pleural effusion. Clin Biochem 2012. [DOI: 10.1016/j.clinbiochem.2012.07.048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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43
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Zhang X, Zhou Y, Xia W, Wu H, Yao K, Liu H, Xiong C. Effect of pre-freezing conditions on the progressive motility recovery rate of human frozen spermatozoa. Andrologia 2012; 44:343-8. [PMID: 22404132 DOI: 10.1111/j.1439-0272.2012.01289.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/08/2012] [Indexed: 11/28/2022] Open
Abstract
We evaluated the effects of sperm concentration, progressive motility, sperm morphology, duration of abstinence and collection season on the progressive motility recovery rate of human frozen spermatozoa to identify characteristics that predict the progressive motility recovery rate of human frozen spermatozoa and improve the protocol for sperm collecting in sperm banks. A total of 14 190 semen samples donated at Zhejiang human sperm bank of China between September 2006 and June 2011 were collected from 1624 donors. Semen was evaluated according to WHO standard procedures for sperm concentration. Progressive motility, sperm morphology, ejaculate collection season and abstinence time were recorded. After freezing and thawing, the progressive motility was assessed. Results showed that sperm concentration, progressive motility and normal morphology were significantly associated with the progressive motility recovery rate of human frozen spermatozoa. In addition, the abstinence time and collection season also significantly affected progressive motility recovery rate. Our results indicated that sperm concentration, progressive motility and normal morphology could be valuable in predicting the progressive motility recovery rate of human frozen spermatozoa. As such, progressive motility recovery may be improved by donating semen when abstinent for 3-5 days and during seasons other than summer.
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Affiliation(s)
- X Zhang
- Family Planning Research Institute, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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44
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Gai X, Wang RP, Xiong C, Steel MJ, Eggleton BJ, Luther-Davies B. Near-zero anomalous dispersion Ge11.5As24Se64.5 glass nanowires for correlated photon pair generation: design and analysis. Opt Express 2012; 20:776-786. [PMID: 22274423 DOI: 10.1364/oe.20.000776] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We show that highly nonlinear chalcogenide glass nanowire waveguides with near-zero anomalous dispersion should be capable of generating correlated photon-pairs by spontaneous four-wave mixing at frequencies detuned by over 17 THz from the pump where Raman noise is absent. In this region we predict a photon pair correlation of >100, a figure of merit >10 and brightness of ~8×10(8) pairs/s over a bandwidth of >15 THz in nanowires with group velocity dispersion of <5 ps∙km(-1) nm(-1). We present designs for double-clad Ge(11.5)As(24)Se(64.5) glass nanowires with realistic tolerance to fabrication errors that achieve near-zero anomalous dispersion at a 1420 nm pump wavelength. This structure has a fabrication tolerance of 80-170 nm in the waveguide width and utilizes a SiO(2)/Al(2)O(3) layer deposited by atomic layer deposition to compensate the fabrication errors in the film thickness.
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Affiliation(s)
- X Gai
- Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), Research School of Physics and Engineering, The Australian National University, Canberra ACT, Australia.
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45
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Xiong C, Monat C, Clark AS, Grillet C, Marshall GD, Steel MJ, Li J, O'Faolain L, Krauss TF, Rarity JG, Eggleton BJ. Slow-light enhanced correlated photon pair generation in a silicon photonic crystal waveguide. Opt Lett 2011; 36:3413-3415. [PMID: 21886228 DOI: 10.1364/ol.36.003413] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report the generation of correlated photon pairs in the telecom C-band at room temperature from a dispersion-engineered silicon photonic crystal waveguide. The spontaneous four-wave mixing process producing the photon pairs is enhanced by slow-light propagation enabling an active device length of less than 100 μm. With a coincidence to accidental ratio of 12.8 at a pair generation rate of 0.006 per pulse, this ultracompact photon pair source paves the way toward scalable quantum information processing realized on-chip.
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Affiliation(s)
- C Xiong
- Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, NSW 2006, Australia.
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46
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47
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Xiong C, Helt LG, Judge AC, Marshall GD, Steel MJ, Sipe JE, Eggleton BJ. Quantum-correlated photon pair generation in chalcogenide As2S3 waveguides. Opt Express 2010; 18:16206-16216. [PMID: 20721006 DOI: 10.1364/oe.18.016206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We theoretically investigate the generation of quantum-correlated photon pairs through spontaneous four-wave mixing in chalcogenide As(2)S(3) waveguides. For reasonable pump power levels, we show that such photonic-chip-based photon-pair sources can exhibit high brightness (approximately 1 x 10(9) pairs/s) and high correlation (approximately 100) if the waveguide length is chosen properly or the waveguide dispersion is engineered. Such a high correlation is possible in the presence of Raman scattering because the Raman profile exhibits a low gain window at a Stokes shift of 7.4 THz, though it is constrained due to multi-pair generation. As the proposed scheme is based on photonic chip technologies, it has the potential to become an integrated platform for the implementation of on-chip quantum technologies.
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Affiliation(s)
- C Xiong
- Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), Institute for Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Australia.
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Abstract
Cauliflower mosaic virus DNA contains six major open reading frames (ORFs). As only the mRNA corresponding to the transcription of gene VI and its translation product have been isolated, the identification in infected plants of products corresponding to the five other putative genes remains to be established. The present paper reports the detection of an ORF III product by means of antibodies raised against an NH(2)-terminal synthetic peptide of 19 amino acids corresponding to a sequence predicted from the nucleotide sequence of ORF III. The detection of this gene product raises the question of the mechanism of its expression.
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Affiliation(s)
- C Xiong
- Laboratoire de Virologie, Institut de Biologie Moléculaire et Cellulaire du Centre National de la Recherche Scientifique, 15 rue Descartes, 67084 Strasbourg Cédex, France
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Ances BM, Christensen JJ, Teshome M, Taylor J, Xiong C, Aldea P, Fagan AM, Holtzman DM, Morris JC, Mintun MA, Clifford DB. Cognitively unimpaired HIV-positive subjects do not have increased 11C-PiB: a case-control study. Neurology 2010; 75:111-5. [PMID: 20534887 DOI: 10.1212/wnl.0b013e3181e7b66e] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVES Diagnostic challenges exist for differentiating HIV dementia from Alzheimer disease (AD) in older HIV-infected (HIV+) individuals. Similar abnormalities in brain amyloid-beta42 (Alphabeta42) metabolism may be involved in HIV-associated neuropathology and AD. We evaluated the amyloid-binding agent (11)C-Pittsburgh compound B ((11)C-PiB), a biomarker for Alphabeta42 deposition, in cognitively unimpaired HIV+ (n = 10) participants and matched community controls without dementia (n = 20). METHODS In this case-control study, all participants had an (11)C-PiB scan within 2 years of concomitant CSF studies and neuropsychometric testing. Statistical differences between HIV+ and community controls for demographic and clinical values were assessed by chi(2) tests. Participants were further divided into either low (<500 pg/mL) or normal (>or=500 pg/mL) CSF Alphabeta42 groups with Student t tests performed to determine if regional differences in fibrillar amyloid plaque deposition varied with CSF Alphabeta42. RESULTS Regardless of CSF Alphabeta42 level, none of the HIV+ participants had fibrillar amyloid plaques as assessed by increased (11)C-PiB mean cortical binding potential (MCBP) or binding potential within 4 cortical regions. In contrast, some community controls with low CSF Alphabeta42 (<500 pg/mL) had high (11)C-PiB MCBP with elevated binding potentials (>0.18 arbitrary units) within cortical regions. CONCLUSIONS Cognitively unimpaired HIV+ participants, even with low CSF Alphabeta42 (<500 pg/mL), do not have (11)C-PiB parameters suggesting brain fibrillar amyloid deposition. The dissimilarity between unimpaired HIV+ and preclinical AD may reflect differences in Abeta42 production and/or formation of diffuse plaques. Future longitudinal studies of HIV+ participants with low CSF Abeta42 and normal (11)C-PiB are required.
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Affiliation(s)
- B M Ances
- Department of Neurology, Washington University, St Louis, MO 63110, USA.
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Roe CM, Fitzpatrick AL, Xiong C, Sieh W, Kuller L, Miller JP, Williams MM, Kopan R, Behrens MI, Morris JC. Cancer linked to Alzheimer disease but not vascular dementia. Neurology 2009; 74:106-12. [PMID: 20032288 DOI: 10.1212/wnl.0b013e3181c91873] [Citation(s) in RCA: 185] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To investigate whether cancer is associated with Alzheimer disease (AD) and vascular dementia (VaD). METHODS Cox proportional hazards models were used to test associations between prevalent dementia and risk of future cancer hospitalization, and associations between prevalent cancer and risk of subsequent dementia. Participants in the Cardiovascular Health Study-Cognition Substudy, a prospective cohort study, aged 65 years or older (n = 3,020) were followed a mean of 5.4 years for dementia and 8.3 years for cancer. RESULTS The presence of any AD (pure AD + mixed AD/VaD; hazard ratio [HR] = 0.41, 95% confidence interval [CI] = 0.20-0.84) and pure AD (HR = 0.31, 95% CI = 0.12-0.86) was associated with a reduced risk of future cancer hospitalization, adjusted for demographic factors, smoking, obesity, and physical activity. No significant associations were found between dementia at baseline and rate of cancer hospitalizations for participants with diagnoses of VaD. Prevalent cancer was associated with reduced risk of any AD (HR = 0.72; 95% CI = 0.52-0.997) and pure AD (HR = 0.57; 95% CI = 0.36-0.90) among white subjects after adjustment for demographics, number of APOE epsilon4 alleles, hypertension, diabetes, and coronary heart disease; the opposite association was found among minorities, but the sample size was too small to provide stable estimates. No significant association was found between cancer and subsequent development of VaD. CONCLUSIONS In white older adults, prevalent Alzheimer disease (AD) was longitudinally associated with a reduced risk of cancer, and a history of cancer was associated with a reduced risk of AD. Together with other work showing associations between cancer and Parkinson disease, these findings suggest the possibility that cancer is linked to neurodegeneration.
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Affiliation(s)
- C M Roe
- Alzheimer Disease Research Center, Washington University School of Medicine, St. Louis, MO 63110, USA.
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