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Lodha A, Yee W, Christianson H, Tang S, Sauve R. Do Sga Infants with Bronchopulmonary Dysplasia (Bpd) have Poorer Neurodevelopmental Outcome than Aga Infants with Bpd at 3 Years of Age? Paediatr Child Health 2009. [DOI: 10.1093/pch/14.suppl_a.32ab] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Lodha A, Yee W, Christianson H, Tang S, Sauve R. Prevalence and Severity of Bronchopulmonary Dysplasia (Bpd) in Infants with Birth Weight = 1250 Grams Born Between 1995–2006 in Southern Alberta. Paediatr Child Health 2009. [DOI: 10.1093/pch/14.suppl_a.24aa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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328
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Lin JH, Wu YQ, Tang S, Fan YL, Yang XJ, Jiang ZM, Zou J. Composition and strain measurements of Ge(Si)/Si(001) islands by HRTEM. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:2753-2757. [PMID: 19438031 DOI: 10.1166/jnn.2009.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The distributions of the composition and the strain in the Ge(Si)/Si(001) coherent islands grown by molecular-beam epitaxy are investigated by digital analysis of high resolution transmission electron microscopy (HRTEM) micrographs. Local composition and strain are obtained from the measurement of the lattice displacement based on the Poisson's formula and Vegard's law. The analysis suggests that the islands have high Ge content at the island's central region. The island is partially relaxed by the substrate deformation and strain concentrated around the edge of islands. The alloying of the islands was found due to the Si surface diffusion.
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Xin Y, Qian J, Xu L, Tang S, Gao J, Critchley JA. The impact of smoking and quitting on household expenditure patterns and medical care costs in China. Tob Control 2009; 18:150-5. [PMID: 19158112 PMCID: PMC2655040 DOI: 10.1136/tc.2008.026955] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Accepted: 01/09/2009] [Indexed: 11/11/2022]
Abstract
BACKGROUND Smoking remains very common in Chinese men, and the economic burden caused by cigarette consumption on smokers and their families may be substantial. Using a large nationally representative household survey, the third National Health Services Survey (NHSS, 2003), we estimated the economic impact of smoking on households. METHODS Smoking status of all household members (over 15 years) was collected by interview for the NHSS, and households classified into one of seven categories based on their smoking status. Information on household income and expenditure, and use of health services was also obtained. We assessed both the "direct" costs (reducing funds available for spending on other commodities such as food, education, medical care, etc, using a fractional logit model), and "indirect costs" (increasing medical expenditures, using a log-linear model). RESULTS Every five packets of cigarettes consumed per capita per month reduces household spending on other commodities, most notably on education (by about 17 yuan per capita per annum) and medical care (11 yuan). The effects are greatest among low-income rural households. Households with quitters spend substantially more on medical care than never-smoking households (64 yuan for households with two or more quitters). CONCLUSIONS If a household member smokes, there is less money available for commodities such as education and medical care. Medical care expenditure is substantially higher among households with quitters, as ill-health is the main reason for quitting smoking in China. Smoking impoverishes a substantial number of poorer rural households.
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Ezra M, Kumar P, Tang S, Dahar N. UP.54: The Multidisciplinary Uro-Oncology Team: Auditing Outcomes. Urology 2008. [DOI: 10.1016/j.urology.2008.08.376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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331
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Yue B, Radi SA, Vick BA, Cai X, Tang S, Knapp SJ, Gulya TJ, Miller JF, Hu J. Identifying quantitative trait loci for resistance to Sclerotinia head rot in two USDA sunflower germplasms. PHYTOPATHOLOGY 2008; 98:926-31. [PMID: 18943211 DOI: 10.1094/phyto-98-8-0926] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Sclerotinia head rot is a major disease of sunflower in the world, and quantitative trait loci (QTL) mapping could facilitate understanding of the genetic basis of head rot resistance and breeding in sunflower. One hundred twenty-three F2:3 and F2:4 families from a cross between HA 441 and RHA 439 were studied. The mapping population was evaluated for disease resistance in three field experiments in a randomized complete block design with two replicates. Disease incidence (DI) and disease severity (DS) were assessed. A genetic map with 180 target region amplification polymorphism, 32 simple sequence repeats, 11 insertion-deletion, and 2 morphological markers was constructed. Nine DI and seven DS QTL were identified with each QTL explaining 8.4 to 34.5% of phenotypic variance, suggesting the polygenic basis of the resistance to head rot. Five of these QTL were identified in more than one experiment, and each QTL explained more than 12.9% of phenotypic variance. These QTL could be useful in sunflower breeding. Although a positive correlation existed between the two disease indices, most of the respective QTL were located in different chromosomal regions, suggesting a different genetic basis for the two indices.
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Kirkpatrick G, Ferguson KA, Gao H, Tang S, Chow V, Yuen BH, Ma S. A comparison of sperm aneuploidy rates between infertile men with normal and abnormal karyotypes. Hum Reprod 2008; 23:1679-83. [DOI: 10.1093/humrep/den126] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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333
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Sahai A, Tang S, Challacombe B, Murphy D, Dasgupta P. Laparoscopic upper urinary tract surgery for benign and malignant conditions. Does aetiology have an effect on health-related quality of life? Int J Clin Pract 2007; 61:2026-9. [PMID: 17997809 DOI: 10.1111/j.1742-1241.2007.01472.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
INTRODUCTION We present health-related quality of life (HRQoL) data on a cohort of patients undergoing upper urinary tract laparoscopy for a variety of benign and malignant conditions. PATIENTS AND METHODS The Short Form 8 (SF-8) Health Survey is a validated HRQoL questionnaire that calculates scores for physical (PCS8) and mental (MCS8) components of health. It was administered prospectively to 58 patients. Radical nephrectomy or nephroureterectomy was carried out for upper tract malignancy (n = 21). Laparoscopy for benign disease (n = 37) included simple nephrectomy for giant hydronephrosis and small non-functioning kidneys, de-roofing of renal cysts and pyeloplasty. Data were collected before and 6 weeks after surgery. RESULTS The mean pre- and postsurgery scores were 45.99; 47.43 and 43.93; 51.54 for PCS8 and MCS8 respectively. With regard to the PCS8 score, there was no significant difference before or after surgery (p = 0.585) or when analysing the benign (p = 0.343) or malignant (p = 0.509) groups individually. The MCS8 score, however, showed a significant increase after surgery (p < 0.0001). This remained significant when analysing just the benign (p < 0.0009) or the malignant (p < 0.0003) groups but neither group was more significant than the other (p = 0.750). CONCLUSIONS Laparoscopic upper urinary tract surgery significantly improves mental and does not appear to reduce physical HRQoL in patients regardless of aetiology, 4 weeks following surgery. Interestingly, those operated on for malignant conditions do not have a greater improvement in mental health when compared with benign disease.
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Zhou Y, Zhu Q, Chen JM, Wang YQ, Liu J, Sun R, Tang S. Observation and simulation of net primary productivity in Qilian Mountain, western China. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2007; 85:574-84. [PMID: 17129660 DOI: 10.1016/j.jenvman.2006.04.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2005] [Revised: 12/12/2005] [Accepted: 04/03/2006] [Indexed: 05/12/2023]
Abstract
We modeled net primary productivity (NPP) at high spatial resolution using an advanced spaceborne thermal emission and reflection radiometer (ASTER) image of a Qilian Mountain study area using the boreal ecosystem productivity simulator (BEPS). Two key driving variables of the model, leaf area index (LAI) and land cover type, were derived from ASTER and moderate resolution imaging spectroradiometer (MODIS) data. Other spatially explicit inputs included daily meteorological data (radiation, precipitation, temperature, humidity), available soil water holding capacity (AWC), and forest biomass. NPP was estimated for coniferous forests and other land cover types in the study area. The result showed that NPP of coniferous forests in the study area was about 4.4 tCha(-1)y(-1). The correlation coefficient between the modeled NPP and ground measurements was 0.84, with a mean relative error of about 13.9%.
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Tang S, Chen JM, Zhu Q, Li X, Chen M, Sun R, Zhou Y, Deng F, Xie D. LAI inversion algorithm based on directional reflectance kernels. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2007; 85:638-48. [PMID: 17129659 DOI: 10.1016/j.jenvman.2006.08.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2004] [Revised: 12/06/2005] [Accepted: 08/23/2006] [Indexed: 05/12/2023]
Abstract
Leaf area index (LAI) is an important ecological and environmental parameter. A new LAI algorithm is developed using the principles of ground LAI measurements based on canopy gap fraction. First, the relationship between LAI and gap fraction at various zenith angles is derived from the definition of LAI. Then, the directional gap fraction is acquired from a remote sensing bidirectional reflectance distribution function (BRDF) product. This acquisition is obtained by using a kernel driven model and a large-scale directional gap fraction algorithm. The algorithm has been applied to estimate a LAI distribution in China in mid-July 2002. The ground data acquired from two field experiments in Changbai Mountain and Qilian Mountain were used to validate the algorithm. To resolve the scale discrepancy between high resolution ground observations and low resolution remote sensing data, two TM images with a resolution approaching the size of ground plots were used to relate the coarse resolution LAI map to ground measurements. First, an empirical relationship between the measured LAI and a vegetation index was established. Next, a high resolution LAI map was generated using the relationship. The LAI value of a low resolution pixel was calculated from the area-weighted sum of high resolution LAIs composing the low resolution pixel. The results of this comparison showed that the inversion algorithm has an accuracy of 82%. Factors that may influence the accuracy are also discussed in this paper.
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Huang F, Yang Q, Chen L, Tang S, Liu W, Yu X. Renal pathological change in patients with type 2 diabetes is not always diabetic nephropathy: a report of 52 cases. Clin Nephrol 2007; 67:293-7. [PMID: 17542338 DOI: 10.5414/cnp67293] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
AIMS The present study examined the relationship between clinical features and renal histological changes in the Type 2-diabetic patients and evaluated the usefulness of renal biopsy in the diagnosis of diabetic versus non-diabetic kidney disease. METHODS 52 patients with Type 2-diabetic mellitus were retrospectively analyzed for differential clinical, laboratory features and pathological characteristics including overt proteinuria (> 0.5 g/day), elevated serum creatinine and/or the development of hematuria. RESULTS Of 52 patients, 20 cases (38.5%) showed no detectable diabetic lesions and, thus, were diagnosed as non-diabetic renal disease (NDRD), while 32 patients (61.5%) exhibited diabetic nephropathy. Interestingly, while 29 patients showed diabetic nephropathy (DN) alone, NDRD was also found in 3 patients with DN. Clinically, 24 out of 52 patients (46.16%) had a diagnosis consistent with the pathological findings, while 10 (19.23%) were diagnosed incorrectly. Compared to NDRD patients, patients with DN had prolonged diabetic history with or without retinopathy, while 25% of patients with NDRD exhibited mesangial proliferative glomerulonephritis. CONCLUSIONS NDRD was a common feature in Type 2-diabetic patients with renal involvement. The absence of retinopathy and short periods of diabetic history may be useful indicators for diagnosis of NDRD clinically.
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Lee S, Wood O, Tang S, Hu J, Machuca A, Kerby S, Awazi B, Vockley C, Hewlett I. Detection of emerging HIV variants in blood donors from urban areas of Cameroon. AIDS Res Hum Retroviruses 2007; 23:1262-7. [PMID: 17961114 DOI: 10.1089/aid.2006.0301] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The U.S. Food and Drug Administration has licensed several assays for use in donor testing and management of persons with human immunodeficiency virus (HIV) infection. However, the performance of these assays for detection and quantitation of emerging HIV genetic variants has not been studied extensively. We tested 240 human plasma specimens collected from two urban blood centers in Cameroon where HIV genetic diversity and recombinant HIV strains are highly prevalent, using several FDA licensed assays. The testing record in Cameroon indicated that 149 specimens were HIV antibody positive and 91 specimens were negative using a rapid HIV-1/2 antibody assay in routine use in Cameroon blood centers. Both sets of samples were evaluated in the FDA laboratory using four ELISA tests for HIV-1 group M, HIV-1 group O, and HIV-2 antibodies, one IFA for HIV-1 antibody, one Western blot for HIV-1, one HIV-1 p-24 antigen assay, and three nucleic acid tests (NAT). Our results indicate that the assays had high sensitivity for detection of emerging genetic variants, although a small number of samples harboring circulating recombinant forms (CRFs) found in Cameroon were not always consistently detected by a few assays. These findings may be due to the evolving genetic diversity of HIV strains in Cameroon.
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Tang S, Zhou Y, Li R, Chen Q, Xiao X. Pharmacokinetics and lung-targeting characterization of a newly formulated enrofloxacin preparation. J Vet Pharmacol Ther 2007; 30:443-50. [PMID: 17803737 DOI: 10.1111/j.1365-2885.2007.00895.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new lung-targeting and controlled releasing preparation, enrofloxacin microsphere, was formulated and its physical properties, stability, pharmacokinetics and lung-targeting characteristics were tested in this study. The enrofloxacin microsphere prepared was demonstrated round and regular, which was easy to be dispersed and stable in both light stability test and heat stability test. Following intravenous administration of a single dose in dog, the drug concentration-time data in the lung were fitted most suitably with three-compartment open model. Compared with enrofloxacin injection (Baytril, half-life of distribution phase in the lung was shortened from 0.72 to 0.16 h, half-life of elimination phase in the lung was prolonged from 5.15 to 33.86 h and clearance of drug concentration in the lung was decreased from 0.603 to 0.267 L/h/kg. Lung-targeting parameters, including the relative intake rate (Re), targeting efficacy (Te) and the ratio of peak concentration (Ce), were calculated according to the pharmacokinetic parameters. The results showed that Re (2.48) and Ce (4.27) of the lung was much greater than that of other tissues and the ratio of Te(microsphere) to Te(Baytril) increased by a factor of 1.77 (compared with liver) to 3.51 (compared with spleen). Therefore, the enrofloxacin microsphere prepared in this study had controlled releasing and lung-targeting effects in dog.
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Pishnyak OP, Tang S, Kelly JR, Shiyanovskii SV, Lavrentovich OD. Levitation, lift, and bidirectional motion of colloidal particles in an electrically driven nematic liquid crystal. PHYSICAL REVIEW LETTERS 2007; 99:127802. [PMID: 17930554 DOI: 10.1103/physrevlett.99.127802] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2007] [Indexed: 05/25/2023]
Abstract
We study electric-field-induced dynamics of colloids in a nematic cell, experimentally and by computer simulations. Solid particles in the nematic bulk create director distortions of dipolar type. Elastic repulsion from the walls keeps the particles in the middle of cell. The ac electric field reorients the dipoles and lifts them to top or bottom, depending on dipole orientation. Once near the walls, the colloids are carried along two antiparallel horizontal directions by nematic backflow. Computer simulations of the backflow agree with the experiment.
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Zhao X, Jiang H, Sun Z, Tang S, Zhou C, Cong Z, Tayo G, Tan Z. Effect of rice straw in the diet for growing goats on site
and extent of digestion and N balance. JOURNAL OF ANIMAL AND FEED SCIENCES 2007. [DOI: 10.22358/jafs/66794/2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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341
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Pisarska M, Kuo F, Tang S, Khan S. Forkhead L2 (FOXL2), a gene associated with premature ovarian failure is likely regulated through phosphorylation. Fertil Steril 2007. [DOI: 10.1016/j.fertnstert.2007.07.582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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342
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Tang S, Chen J, Zhang Z. Structured models for recombinant human interleukin-11 fermentation. Biochem Eng J 2007. [DOI: 10.1016/j.bej.2007.01.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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343
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Li Z, Zou HY, Shao CP, Tang S, Wang DM. Identification of a novel HLA-B*56 allele, B*5618 and an extension of B*2736 by sequence-based typing. ACTA ACUST UNITED AC 2007; 69:365-6. [PMID: 17389027 DOI: 10.1111/j.1399-0039.2006.00796.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report the identification of a novel human leukocyte antigen (HLA)-B*56 allele, B*5618 and an extension of B*2736 that were found during routine high-resolution sequence-based typing in Chinese Han individual. The B*5618 allele has 4nt changes from B*5610 in exon 3, The B*2736 allele has 10nt changes from B*270401 in exons 3-4.
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Farrell A, Tang S, Nomura M, Brauner C, von Keyserlingk N, Sloman K. Assessing fish welfare during commercial live hauling. Comp Biochem Physiol A Mol Integr Physiol 2007. [DOI: 10.1016/j.cbpa.2007.01.097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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345
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Zhou W, Liu H, Zhang F, Tang S, Zhu H, Lai M, Kalivas PW. Role of acetylcholine transmission in nucleus accumbens and ventral tegmental area in heroin-seeking induced by conditioned cues. Neuroscience 2006; 144:1209-18. [PMID: 17184925 PMCID: PMC1868450 DOI: 10.1016/j.neuroscience.2006.11.013] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Revised: 11/06/2006] [Accepted: 11/08/2006] [Indexed: 01/21/2023]
Abstract
The involvement of cholinergic transmission in heroin self-administration and the reinstatement of heroin-seeking was examined in rats trained to nose-poke for i.v. heroin. Systemic treatment with physostigmine, an inhibitor of acetylcholinesterase, modestly reduced the acquisition and rate of heroin self-administration, and this suppression of heroin intake was reversed by pretreatment with scopolamine but not by mecamylamine. Following 10-14 days of self-administration, rats were left in the home environment for 14 days. Subsequently, rats were evaluated for extinction of nose-pokes during the first hour after being returned to the self-administration apparatus. One hour later a conditioned stimulus (house light, light in the nose-poke hole, sound of the infusion pump) was presented to initiate cue-induced reinstatement. Physostigmine produced a dose-dependent inhibition of cue-induced reinstatement, but only the dose of 0.5 mg/kg significantly decreased nose-poke responding in the extinction test. Chronic treatment with physostigmine (0.1 mg/kg) did not impair performance during acquisition of heroin self-administration. However, during a subsequent reinstatement test conducted in the absence of physostigmine pretreatment, heroin seeking was significantly below that of rats chronically pretreated with saline. To evaluate brain regions mediating the effects of systemic drug treatment on reinstatement, physostigmine was microinjected into the nucleus accumbens (NAc) or ventral tegmental area (VTA). Microinjection of physostigmine into the NAc prior to presenting conditioned cues inhibited the reinstatement of heroin-seeking, without affecting extinction responding. In contrast, microinjection of physostigmine into the VTA augmented the reinstatement induced by conditioned cues and extinction responding. Inactivation of either NAc or VTA by microinjecting tetrodotoxin blocked both extinction responding and cue-induced reinstatement. These data demonstrate that cholinergic transmission influences heroin self-administration and reinstatement. Moreover, cue-induced reinstatement was inhibited by physostigmine in the NAc and potentiated by cholinergic stimulation in the VTA.
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Tan EK, Zhao Y, Skipper L, Tan MG, Di Fonzo A, Sun L, Fook-Chong S, Tang S, Chua E, Yuen Y, Tan L, Pavanni R, Wong MC, Kolatkar P, Lu CS, Bonifati V, Liu JJ. The LRRK2 Gly2385Arg variant is associated with Parkinson’s disease: genetic and functional evidence. Hum Genet 2006; 120:857-63. [PMID: 17019612 DOI: 10.1007/s00439-006-0268-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Accepted: 09/11/2006] [Indexed: 10/24/2022]
Abstract
Evidence of LRRK2 haplotypes associated with Parkinson's disease (PD) risk was recently found in the Chinese population from Singapore, and a common LRRK2 missense variant, Gly2385Arg, was independently detected as a putative risk factor for PD in the Chinese population from Taiwan. To test the association between the Gly2385Arg variant in a large case-control sample of Chinese ethnicity from Singapore, and to perform functional studies of the wild type and Gly2385Arg LRRK2 protein in human cell lines. In a case-control study involving 989 Chinese subjects, the frequency of the heterozygous Gly2385Arg genotype was higher in PD compared to controls (7.3 vs. 3.6%, odds ratio = 2.1, 95% CI: 1.1-3.9, P = 0.014); these values yield an estimated population attributable risk (PAR) of approximately 4%. In a multivariate logistic regression analysis with the disease group (PD vs. controls) as the dependent variable and the genotype as an independent factor with adjustments made for the effect of age and gender, the heterozygous Gly2385Arg genotype remained associated with an increased risk of PD compared to wild type genotype (odds ratio = 2.67, 95% CI: 1.43-4.99, P = 0.002). The glycine at position 2385 is a candidate site for N-myristoylation, and the Gly2385Arg variant replaces the hydrophobic glycine with the hydrophilic arginine, and increases the net positive charge of the LRRK2 WD40 domain. In transfection studies, we demonstrated that both the wild type and Gly2385Arg variant LRRK2 protein localize to the cytoplasm and form aggregates. However, under condition of oxidative stress, the Gly2385Arg variant was more toxic and associated with a higher rate of apoptosis. Our study lends support to the contention that the Gly2385Arg is a common risk factor for PD in the Chinese population. Our bioinformatics and in-vitro studies also suggest that the Gly2385Arg variant is biologically relevant and it might act through pro-apoptotic mechanisms.
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Tang S, Lai KN. Hepatitis B-related membranous nephropathy should be treated with a specific anti-viral agent. Kidney Int 2006; 70:818. [PMID: 16900222 DOI: 10.1038/sj.ki.5001586] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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348
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Tang S, Tan Z, Zhou C, Jiang H, Jiang Y, Sheng L. A comparison of in vitro fermentation
characteristics of different botanical fractions
of mature maize stover. JOURNAL OF ANIMAL AND FEED SCIENCES 2006. [DOI: 10.22358/jafs/66920/2006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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349
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Tang S, Tao M, McCoy JP, Zheng ZM. Short-term induction and long-term suppression of HPV16 oncogene silencing by RNA interference in cervical cancer cells. Oncogene 2006; 25:2094-104. [PMID: 16369495 DOI: 10.1038/sj.onc.1209244] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
RNA interference-mediated gene silencing has the potential to block gene expression. A synthetic double-stranded small interfering RNA (siRNA) based on a sequence motif of 21 nucleotides from human papillomavirus 16 (HPV16) E6E7 bicistronic RNA was found to be a potent siRNA that suppresses expression of both the E6 and E7 oncogenes in HPV16+ CaSki and SiHa cells. When stably expressed as a short hairpin RNA in these cells, however, siRNA silencing of E6 and E7 expression was efficient only at early cell passages, but became inefficient with increased cell passages despite the continued expression of the siRNA at the same level. The loss of the siRNA function was duplicable in stable p53 siRNA cells, but not in stable lamin A/C siRNA cells, suggesting that it is gene selective. The cells resistant to siRNA function retained normal siRNA processing, duplex unwinding and degradation of the unwound sense strand and RNA-induced silencing complex formation, suggesting that loss of the siRNA function occurred at a later step. Surprisingly, the siRNA-resistant cells were found to express notably a cytoplasmic protein of approximately 50 kDa that specifically and characteristically interacted with the unwound, antisense strand E7 siRNA. Altogether, our data indicate that a potent siRNA targeting to an essential or regulatory gene might induce a cell to develop siRNA-suppressive function.
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Patrawala L, Calhoun T, Schneider-Broussard R, Li H, Bhatia B, Tang S, Reilly JG, Chandra D, Zhou J, Claypool K, Coghlan L, Tang DG. Highly purified CD44+ prostate cancer cells from xenograft human tumors are enriched in tumorigenic and metastatic progenitor cells. Oncogene 2006; 25:1696-708. [PMID: 16449977 DOI: 10.1038/sj.onc.1209327] [Citation(s) in RCA: 709] [Impact Index Per Article: 39.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
CD44 is a multifunctional protein involved in cell adhesion and signaling. The role of CD44 in prostate cancer (PCa) development and progression is controversial with studies showing both tumor-promoting and tumor-inhibiting effects. Most of these studies have used bulk-cultured PCa cells or PCa tissues to carry out correlative or overexpression experiments. The key experiment using prospectively purified cells has not been carried out. Here we use FACS to obtain homogeneous CD44(+) and CD44(-) tumor cell populations from multiple PCa cell cultures as well as four xenograft tumors to compare their in vitro and in vivo tumor-associated properties. Our results reveal that the CD44(+) PCa cells are more proliferative, clonogenic, tumorigenic, and metastatic than the isogenic CD44(-) PCa cells. Subsequent molecular studies demonstrate that the CD44(+) PCa cells possess certain intrinsic properties of progenitor cells. First, BrdU pulse-chase experiments reveal that CD44(+) cells colocalize with a population of intermediate label-retaining cells. Second, CD44(+) PCa cells express higher mRNA levels of several 'stemness' genes including Oct-3/4, Bmi, beta-catenin, and SMO. Third, CD44(+) PCa cells can generate CD44(-) cells in vitro and in vivo. Fourth, CD44(+) PCa cells, which are AR(-), can differentiate into AR(+) tumor cells. Finally, a very small percentage of CD44(+) PCa cells appear to undergo asymmetric cell division in clonal analyses. Altogether, our results suggest that the CD44(+) PCa cell population is enriched in tumorigenic and metastatic progenitor cells.
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