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Yin F, Luo SL, Yuan F, Peng Z, Zhou W, Fang L, Cai JF. Regulation different network analysis of rheumatoid arthritis (RA) and osteoarthritis (OA). EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2013; 17:2504-2511. [PMID: 24089231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
BACKGROUND Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic synovitis that progresses to destruction of cartilage and bone. AIM The purpose of this study was to employ microarray analysis combined with bioinformatics techniques to evaluate differential gene expression in BM-derived mononuclear cells obtained from patients with rheumatoid arthritis (RA) or osteoarthritis (OA) to study the pathogenesis of this disease. MATERIALS AND METHODS Gene expression profiles in BM-derived mononuclear cells from 9 RA and 10 OA patients were obtained from GEO. RESULTS The bone marrow (BM) mononuclear cells showed 2581 up-regulated and 649 down-regulated genes in RA patients relative to the OA group: Our analysis indicated that several differentially expressed genes might play crucial roles in RA development, including SP1, RARA, ETS1, ETS2, FOS and ESR1. CONCLUSIONS Further analysis predicted these genes might be involved in RA through cancer related pathways and immunity related pathways. Furthermore, these genes may serve as novel therapeutic targets for the treatment of RA.
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Han T, Zeng F, Li Z, Liu L, Wei M, Guan Q, Liang X, Peng Z, Liu M, Qin J, Zhang S, Jia B. Biochemical characterization of a recombinant pullulanase from Thermococcus kodakarensis
KOD1. Lett Appl Microbiol 2013; 57:336-43. [DOI: 10.1111/lam.12118] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 06/10/2013] [Accepted: 06/10/2013] [Indexed: 11/27/2022]
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Liu RX, Li QZ, Xing LL, Peng Z, Zhu CM, Yang ZH. Genotyping of clinical Mycobacterium tuberculosis isolates based on eight loci of MIRU-VNTR. Int J Tuberc Lung Dis 2013; 17:243-5. [PMID: 23317961 DOI: 10.5588/ijtld.12.0777] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Genotyping that differentiates between strains of Mycobacterium tuberculosis based on variations in the genome of the organism is a useful tool for molecular epidemiological studies of tuberculosis. In the present study, we identified a combination of five mycobacterial interspersed repetitive unit (MIRU) loci and three variable numbers of tandem repeats (VNTR) loci of M. tuberculosis that showed a discriminatory power comparable to that of the 15 to 24 loci-based typing proposed for international standardisation in analysing 210 paediatric isolates obtained from Chongqing, China.
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Zhao L, Chen J, Cheng L, Wang X, Du J, Wang F, Peng Z. Effects of Enterococcus faecalis lipoteichoic acid on receptor activator of nuclear factor-κB ligand and osteoprotegerin expression in periodontal ligament fibroblasts. Int Endod J 2013; 47:163-72. [PMID: 23710898 DOI: 10.1111/iej.12127] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 04/17/2013] [Indexed: 01/01/2023]
Abstract
AIM To investigate the influence of Enterococcus faecalis lipoteichoic acid (LTA) on the key bone resorption-regulating proteins, receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG) in human periodontal ligament fibroblasts (PDL cells). METHODOLOGY Periodontal ligament cells were subjected to various concentrations of LTA. Cell viability was then determined by methyl thiazolyl tetrazolium (MTT) assay, whilst the expression levels of RANKL and OPG were investigated by enzyme-linked immunosorbent assay (ELISA) and Western blotting. The effect of the inhibitors [IL-1 receptor-associated kinase (IRAK)-1/4, p38 mitogen-activated protein kinase (MAPK) (SB203580)] on LTA-stimulated RANKL/OPG activation was examined. Cell viability and RANKL/OPG ratio in PDL cells were also analysed by MTT assay and Western blotting. Data were analysed using one-way anova or t-test at a significance level of P = 0.05. RESULT Cell viability was reduced significantly in the LTA group in a dose-dependent fashion (P < 0.05). In addition, LTA was found to upregulate the protein expression of RANKL, OPG and their relative ratio in PDL cells (P < 0.05). The optimal concentration of LTA used in PDL cells was determined to be 10 μg mL(-1) . Following IRAK1/4 and p38MAPK inhibition, LTA-stimulated increases of RANKL/OPG ratio were significantly reduced (P < 0.05). CONCLUSION Enterococcus faecalis LTA could upregulate the expression of RANKL and OPG at different rates, suggesting a potential role for LTA in the bone resorption process of refractory apical periodontitis through the regulation of RANKL and OPG. In addition, IRAK1/4 and p38MAPK signalling involving RANKL/OPG may contribute to inflammatory responses from PDL cells.
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Peng Z, Liufu Y, Zhang L, Chen J. Syntheses and Properties of New Double-tail Trisiloxane Surfactants with Both Hydrolysis Resistance and High Spreading Ability. TENSIDE SURFACT DET 2013. [DOI: 10.3139/113.110116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
New double-tail trisiloxane surfactants of the general formula R1NR2CH2CH(OH)CH2O(CH2CH2O)xCH3 (R1 = Me3SiOSiMe(CH2)3 · OSiMe3; R2 = Me3SiOSiMe((CH2)3OCH2CH(OH)CH2)OSiMe3; x = 8.4, 12.9, 17.5, 22) have been synthesized. The spreading ability (SA) values of the double-tail trisiloxane surfactants solutions (1.0 × 10−3 mol/L) with average ethoxy units of 8.4, 12.9 and 17.5 on ficus microcarpa leave surface are more than 9 within 3 minutes, and their SA values on the parafilm surface are over 15 within 10 minutes at a concentration of 5.0 × 10−3 mol/L. In alkaline environment (pH = 10.0) the hydrolysis resistant ability (HRA) of the double-tail trisiloxane surfactant containing average ethoxy units of 8.4 with the surface tension of aqueous solution (1.0 × 10−3 mol/L) of less than 23 mN/m over 170 days, is far better than the others’. It is suggested that a more flexible spacer between hydrophobic groups and hydrophilic groups in double-tail trisiloxane surfactants molecules, not only can improve their SA on low-energy solid surfaces, but also improve their HRA.
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Zhou F, Peng Z, Zhang W, Bishop J, Song Q. Is norepinephrine more effective than other vasopressors for septic shock? A systematic review and meta-analysis. Crit Care 2013. [PMCID: PMC3642544 DOI: 10.1186/cc12159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Ma J, Chen P, Xu G, Peng Z, Yang C, Shu D, Wang J, Luo C, Qu H. Sperm competition greatly decreases the time interval when breeder hens are artificially inseminated by different cockerels. J APPL POULTRY RES 2013. [DOI: 10.3382/japr.2012-00532] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Guan Q, Ma Y, Aboud L, Weiss CR, Qing G, Warrington RJ, Peng Z. Targeting IL-23 by employing a p40 peptide-based vaccine ameliorates murine allergic skin and airway inflammation. Clin Exp Allergy 2013; 42:1397-405. [PMID: 22925326 DOI: 10.1111/j.1365-2222.2012.04022.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Studies have found that the IL-23/Th17 pathway plays an important role in the pathogenesis of atopic dermatitis (AD) and severe and steroid-resistant asthma. Targeting IL-23/Th17 pathway with monoclonal antibodies (mAb) has been successful in the reduction of skin and airway inflammation in animal models. However, the mAb has a short half-life, requiring repeated administrations. For the long-term suppression of IL-23/Th17 pathway, we have previously developed an IL-23p40 peptide-based virus-like particle vaccine, which induces long-lasting autoantibodies to IL-23. OBJECTIVE We sought to evaluate the effects of this IL-23p40 peptide-based vaccine on the down-regulation of allergic skin and airway inflammation in mice. METHODS Mice were subcutaneously injected three times with the IL-23p40 vaccine, or the vaccine carrier protein or saline as controls. Two weeks later, mice were epicutaneously sensitized with ovalbumin four times at a 2-week interval. One week after the final sensitization, mice were nasally administrated with ovalbumin daily for 3 days. One day later, bronchoalveolar lavage fluids (BALF), sera, lung and skin tissues were obtained and analysed. RESULTS Mice immunized with the vaccine produced high levels of IgG antibodies to IL-23, p40 and IL-12 that in vitro inhibited IL-23-dependent IL-17 production. The numbers of total cells, neutrophils, and eosinophils in BALF were significantly reduced in the vaccine group, compared with controls. The levels of IL-13, IL-5, IL-23 and, IL-17 in BALF and levels of serum ovalbumin-specific IgE, IgG1, and total IgE were also significantly decreased. Histological analysis showed less inflammation of the lung and skin tissues in the vaccine group, compared with controls. CONCLUSION AND CLINICAL RELEVANCE Administration of an IL-23p40 peptide-based vaccine down-regulates allergic skin and airway inflammation, suggesting that this strategy may be a potential therapeutic approach in the treatment of AD and asthma.
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Li C, Peng Z, Skoog L, Hjelm-Eriksson M, Ährlund-Richter L, Harmenberg U, Pawitan Y, Cedermark GC, Nistér M, Nilsson S. A Prostate Cancer Expression Signature to Predict Survival Benefit of Primary Hormone Therapy. Ann Oncol 2012. [DOI: 10.1016/s0923-7534(20)33463-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Peng Z, Guan Q, Warrington R. Letter to the Editor. Clin Exp Allergy 2012. [DOI: 10.1111/j.1365-2222.2012.04067.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Wang Y, Li J, Chen J, Liu L, Peng Z, Ding J, Ding K. From cirrhosis to hepatocellular carcinoma in HCV-infected patients: genes involved in tumor progression. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2012; 16:995-1000. [PMID: 22913147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
BACKGROUND Hepatocellular carcinoma (HCC) is an aggressive tumor with poor prognosis. Understanding molecular changes in hepatocellular carcinoma should improve identification of risk factors in molecular subtypes and provide potential targets for early detection and therapy. AIM The present study aimed to analyze the molecular mechanism of the transition from hepatitis C virus (HCV) induced cirrhosis to HCV induced HCC using microarray analysis combined with bioinformatics techniques. METHODS, To accomplish this, we performed the differential coexpression analysis of hepatic gene expression in samples of HCV-cirrhotic patients with and without HCC. Total 465 genes were identified and some of them were used to construct a regulatory network. RESULTS Our analysis indicated that several differentially co-express genes might play crucial roles in HCC development, including NA3C2, AHR, MYC, FOXO1 and FOSB. Further analysis predicted these genes might be involved in HCC through pathways of "ribosome", "steroid biosynthesis", "spliceosome" and so on. Moreover, these genes may serve as potential therapeutic targets for the treatment of HCC. CONCLUSIONS In conclusion, our findings confirm the presence of multiple molecular alterations during HCV-infected HCC hepatocarcinogenesis and indicate the possibility for identifying prognostic factors associated with HCC progression.
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Ning Y, Hu X, Ling J, Du Y, Liu J, Liu H, Peng Z. Candida albicans survival and biofilm formation under starvation conditions. Int Endod J 2012; 46:62-70. [PMID: 22757642 DOI: 10.1111/j.1365-2591.2012.02094.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 05/30/2012] [Indexed: 11/30/2022]
Abstract
AIM To investigate the survival and biofilm formation capacity of Candida albicans in starvation and under anaerobic conditions. METHODOLOGY Candida albicans growth and survival were monitored in vitro for up to 8 months. Fungal suspensions from late exponential, stationary and starvation phases were incubated on human dentine, polystyrene and glass slides. Scanning electron microscopy (SEM) was used to observe the process of biofilm formation. 2,3-bis(2-Methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxyanilide inner salt (XTT) reduction assay was performed to quantify the biofilm formation capability, and confocal laser scanning microscopy (CLSM) was used to study and make semi-quantitative comparisons of the ultrastructure of biofilms formed on human dentine. 'XTT bioactivity' and 'COMSTAT results' were analysed by two-way analysis of variance (ANOVA) and one-way ANOVA, respectively. RESULTS Candida albicans survived for over six months. SEM demonstrated that starving C. albicans produced mature biofilms on different substrata. C. albicans of the same growth phase incubated on human dentine displayed significantly higher biofilm formation capability than on polystyrene or glass slides (P < 0.05). Biofilm formation capability by starving cells was significantly lower than that in exponential or stationary phases (P < 0.05). CLSM revealed that biofilms formed by starvation-phase cells were less complex, had a higher roughness coefficient and surface/volume ratio (P < 0.05). CONCLUSIONS Candida albicans cells can survive and form biofilms in anaerobic and nutrient-limited conditions and may pose a treatment challenge.
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Peng Z, Chien SY, Redfern SAT. Dynamic mechanical relaxation and loss in the incommensurate phase of quartz. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:255403. [PMID: 22647673 DOI: 10.1088/0953-8984/24/25/255403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The dynamic mechanical properties of quartz have been studied as a function of temperature across the α-β phase transition and in the vicinity of the incommensurate (IC) phase on cooling from the β phase. The mechanical response of the IC phase shows strong anelasticity for measurement of Young's modulus (closely related to C(11) in our geometry) with modulated stress driven at 1 Hz. The dynamic shear modulus does not show similar strong effects in its imaginary component, although a very weak anomaly is barely detectable in the real part of the modulus. Our results indicate that the incommensurate microstructures within the quartz transition interval are susceptible to dilatational stress with relaxation times around 1 s.
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Li X, Zhang D, Xiao S, Peng Z. Four novel mutations of the ATP2C1 gene in Chinese patients are associated with familial benign chronic pemphigus. Clin Exp Dermatol 2012; 37:797-9. [PMID: 22607350 DOI: 10.1111/j.1365-2230.2012.04364.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Guan Q, Moreno S, Weiss C, Gefei Q, Halayko A, Warrington R, Peng Z. Myeloid Derived Suppressor Cells Attenuate Murine Allergic Airway Inflammation. J Allergy Clin Immunol 2012. [DOI: 10.1016/j.jaci.2011.12.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Thompson A, Peng Z, Pastrana M, Haq I, Okun M, Foote K. 1.234 INTRAOPERATIVE SMILE IN A MULTIPLE SCLEROSIS PATIENT WITH MEDICATION-REFRACTORY TREMOR. Parkinsonism Relat Disord 2012. [DOI: 10.1016/s1353-8020(11)70292-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Xing L, Liu R, Li Q, Peng Z, Zhu C. Clinical and genotypic characteristics of childhood tuberculosis in Chongqing, China. Eur J Clin Microbiol Infect Dis 2011; 31:1735-9. [PMID: 22161015 DOI: 10.1007/s10096-011-1494-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 11/09/2011] [Indexed: 11/24/2022]
Abstract
The aims of this study were to assess the prevalence of isolates of Beijing lineage in childhood tuberculosis (TB) and the association between strain family and clinical characteristics. A total of 105 children aged less than 18 years with culture-confirmed TB were evaluated by spoligotyping and the 12-locus mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) scheme. Of 105 isolates spoligotyped, the major spoligotypes found were Beijing plus Beijing-like lineages (64.8%), followed by T1 lineages (12.3%) and MANU2 lineages (5.7%). MIRU typing identified 72 types that defined 17 clusters and 55 unique isolates. The largest cluster was 223325173533, which belongs to the Beijing lineage. Children in rural areas accounted for 68.8% and 50.5% of the children with TB were older than 5 years. Extrapulmonary tuberculosis accounted for 67.6%, and tuberculous meningitis (TBM) 53.3%. There was no association with clinical characterization (P>0.05). In conclusion, Beijing isolates are the dominant genotype family in children in China. Beijing and non-Beijing strains did not differ in their propensities to cause extrapulmonary tuberculosis in general or meningitis in particular and there was no significant difference between children infected with Beijing strains and those infected with non-Beijing strains with respect to the clinical features.
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Wu JP, Kirk TB, Peng Z, Miller K, Zheng MH. UTILIZATION OF TWO-DIMENSIONAL FAST FOURIER TRANSFORM AND POWER SPECTRAL ANALYSIS FOR ASSESSMENT OF EARLY DEGENERATION OF ARTICULAR CARTILAGE. ACTA ACUST UNITED AC 2011. [DOI: 10.1142/s0218957705001564] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Degeneration of articular cartilage begins from deterioration of the collagen fibres in the superficial zone. Standard histology using 2D imaging technique is often used to determine the microstructure of collagen fibres and the physiological functions of articular cartilage. However, information of the 3D collageneous structure in the cartilage could be lost and misinterpreted in 2D observations. In contrast, confocal microscopy permits studying the 3D internal structure of bulk articular cartilage with minimal physical disturbing. Using fibre optic laser scanning confocal microscopy, a 3D histology has been previously developed to visualize the collagen matrix in the superficial zone by means of identifying the early arthritic changes in articular cartilage. In this study, we characterized the collagen orientation in the superficial zone of normal cartilage, the cartilage with surface disruption and fibrillated cartilage using Fast Fourier transforms and power spectral analysis techniques. Thus, we have established an objective method for assessing the early pathology changes in the articular cartilage.
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Sun G, Jin P, Li M, Lu Y, Liu X, Li F, Xie Z, Ding J, Peng Z. Percutaneous vertebroplasty for pain management in spinal metastasis with epidural involvement. Technol Cancer Res Treat 2011; 10:267-74. [PMID: 21517133 DOI: 10.7785/tcrt.2012.500202] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Percutaneous vertebroplasty (PVP) has been widely used for the treatment of painful malignant lesions of the spine. Spinal metastasis with epidural involvement, with or without symptoms of neurologic compression, is regarded by some authors as a contraindication or relative contraindication to the procedure. To evaluate safety and effectiveness of PVP in pain management of spinal metastasis with epidural involvement, we retrospectively analyzed PVP in 32 patients with metastatic disease, who presented with at least one vertebral lesion with destruction of the posterior vertebral body wall or epidural extension of tumor. Among these patients, nine had signs of spinal cord or cauda equina compression. Procedural safety was evaluated by any post-procedure adverse events. The PVP analgesic efficacy was evaluated by follow-up neurological examination. Pain intensity was scored on a visual analog scale scored from 0 (no pain) to 10 (maximum pain intensity). The effective pain relief was defined as at least 50% improvement in pain score as compared with pre- procedure baseline. Follow-up assessments were performed at 1 day; 1 week; 1, 3, and 6 months after the procedure. Fifty-three vertebrae in 32 patients were treated in this group. Analgesic efficacy in survival patients was rated at 97% (31/32) at 1day and 1 week, 86.7% (26/30) at 1 month, 82.3% (24/29) at 3 months, and 76.9% (20/26) at 6 months after procedure. Leakage of PMMA was detected in 64% (33/53) treated vertebrae. No systemic complications were observed in all treated patients.
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Zhang Y, Ryder OA, Fan Z, Zhang H, He T, He G, Zhang A, Fei L, Zhong S, Chen H, Zhang C, Yang M, Zhu F, Peng Z, Pu T, Chen Y, Yao M, Guo W. Sequence variation and genetic diversity in the giant panda. ACTA ACUST UNITED AC 2011; 40:210-6. [PMID: 18726318 DOI: 10.1007/bf02882050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/1996] [Indexed: 10/22/2022]
Abstract
About 336-444 bp mitochondrial D-loop region and tRNA gene were sequenced for 40 individuals of the giant panda which were collected from Mabian, Meigu, Yuexi, Baoxing, Pingwu, Qingchuan, Nanping and Baishuijiang, respectively. 9 haplotypes were found in 21 founders. The results showed that the giant panda has low genetic variations, and that there is no notable genetic isolation among geographical populations. The ancestor of the living giant panda population perhaps appeared in the late Pleistocene, and unfortunately, might have suffered bottleneck attacks. Afterwards, its genetic diversity seemed to recover to some extent.
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Tajik N, Peng Z, Kuyanov P, LaPierre RR. Sulfur passivation and contact methods for GaAs nanowire solar cells. NANOTECHNOLOGY 2011; 22:225402. [PMID: 21454946 DOI: 10.1088/0957-4484/22/22/225402] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The effect of sulfur passivation on core-shell p-n junction GaAs nanowire (NW) solar cells has been investigated. Devices of two types were investigated, consisting of indium tin oxide contact dots or opaque Au finger electrodes. Lateral carrier transport from the NWs to the contact fingers was achieved via a p-doped GaAs surface conduction layer. NWs between the opaque contact fingers had sidewall surfaces exposed for passivation by sulfur. The relative cell efficiency increased by 19% upon passivation. The contribution of the thin film grown between the NWs to the total cell efficiency was estimated by removing the NWs using a sonication procedure. Mechanisms of carrier transport and photovoltaic effects are discussed on the basis of spatially resolved laser scanning measurements.
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Tian Y, Peng Z, Gorton D, Xiao Y, Ketheesan N. Immunohistochemical analysis of structural changes in collagen for the assessment of osteoarthritis. Proc Inst Mech Eng H 2011; 225:680-7. [DOI: 10.1177/0954411911402135] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Collagen fibrillation within articular cartilage (AC) plays a key role in joint osteoarthritis (OA) progression and, therefore, studying collagen synthesis changes could be an indicator for use in the assessment of OA. Various staining techniques have been developed and used to determine the collagen network transformation under microscopy. However, because collagen and proteoglycan coexist and have the same index of refraction, conventional methods for specific visualization of collagen tissue is difficult. This study aimed to develop an advanced staining technique to distinguish collagen from proteoglycan and to determine its evolution in relation to OA progression using optical and laser scanning confocal microscopy (LSCM). A number of AC samples were obtained from sheep joints, including both healthy and abnormal joints with OA grades 1 to 3. The samples were stained using two different trichrome methods and immunohistochemistry (IHC) to stain both colourimetrically and with fluorescence. Using optical microscopy and LSCM, the present authors demonstrated that the IHC technique stains collagens only, allowing the collagen network to be separated and directly investigated. Fluorescently-stained IHC samples were also subjected to LSCM to obtain three-dimensional images of the collagen fibres. Changes in the collagen fibres were then correlated with the grade of OA in tissue. This study is the first to successfully utilize the IHC staining technique in conjunction with laser scanning confocal microscopy. This is a valuable tool for assessing changes to articular cartilage in OA.
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Huguet P, Morin A, Gebel G, Deabate S, Sutor A, Peng Z. In situ analysis of water management in operating fuel cells by confocal Raman spectroscopy. Electrochem commun 2011. [DOI: 10.1016/j.elecom.2011.02.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Schuettler J, Peng Z, Zimmer J, Sinn P, von Hagens C, Strowitzki T, Vogt PH. Variable expression of the Fragile X Mental Retardation 1 (FMR1) gene in patients with premature ovarian failure syndrome is not dependent on number of (CGG)n triplets in exon 1. Hum Reprod 2011; 26:1241-51. [PMID: 21335413 DOI: 10.1093/humrep/der018] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Increased expression of the Fragile X Mental Retardation 1 (FMR1) gene in blood cells has been claimed to be associated with variable (CGG)(n) triplet numbers in the 5' untranslated region of this gene. Increased CGG triplet numbers, including that of the so-called premutation range (n= 55-200), were shown to have a risk of <26% to impair ovarian reserve leading to primary ovarian insufficiency and premature ovarian failure (POF). METHODS DNA and RNA samples were isolated from 74 patients with idiopathic POF to evaluate quantitatively the expression of FMR1 in leukocytes and CGG triplet number on FMR1 gene alleles. mRNA levels were normalized and compared with those of control women. Expression of the encoded protein (FMRP) was analysed by immunohistochemistry on ovarian biopsy tissue sections. RESULTS A large variance of the FMR1 transcript level was found in the leukocyte RNA samples, but only in patients with POF, and this variability did not correlate to variance of CGG triplet numbers found on both FMR1 alleles (19 < n > 90). During normal folliculogenesis, FMRP is predominantly expressed in granulosa cells. CONCLUSIONS Our data suggest that FMR1 expression during human folliculogenesis is probably a quantitative trait. Proper function of FMRP in granulosa cells seems to depend on an optimal transcript level. All women with CGG triplet numbers outside the range associated with normal folliculogenesis (26 < n > 34) are therefore expected to have a relaxed FMR1 transcription control. FMR1 transcript levels in leukocytes might therefore be diagnostic for altered FMRP levels in granulosa cells, which will affect the process of folliculogenesis.
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