1151
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Li G, Li WK. Least absolute deviation estimation for fractionally integrated autoregressive moving average time series models with conditional heteroscedasticity. Biometrika 2008. [DOI: 10.1093/biomet/asn014] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Walton TJ, Li G, Seth R, McArdle SE, Bishop MC, Rees RC. DNA demethylation and histone deacetylation inhibition co-operate to re-express estrogen receptor beta and induce apoptosis in prostate cancer cell-lines. Prostate 2008; 68:210-22. [PMID: 18092350 DOI: 10.1002/pros.20673] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Epigenetic silencing mechanisms are increasingly thought to play a major role in the development of human cancers, including prostate cancer. Promoter CpG island hypermethylation and histone hypoacetylation, catalyzed by DNA methyltransferase (DNMT) and histone deacetylase (HDAC), respectively, are associated with transcriptional repression in a number of cancers. Evidence is accumulating the two mechanisms are dynamically linked, yet few studies have examined a potential interaction in prostate cancer. METHODS LNCaP, DU-145, and PC-3 prostate cancer cells were co-treated with a DNMT inhibitor, 5'-aza-2'-deoxycytidine (5-AZAC), and an HDAC inhibitor, trichostatin A (TSA). Following treatment cells were processed for cell proliferation/apoptosis assays, or harvested for real-time RT-PCR. Assessed target genes were estrogen receptor beta (ERbeta), estrogen receptor alpha (ERalpha), androgen receptor (AR), progesterone receptor (PGR), and prostate specific antigen (PSA). RESULTS In all cell-lines, co-treatment was associated with reduced cell proliferation compared with control groups (P<0.05). A reciprocal rise in caspase activation was identified, indicating apoptosis was the major mechanism of cell death. Most marked effects were seen in the androgen-dependent, AR-positive LNCaP cell-line. In all cell-lines, an additive re-expression of ERbeta was identified in the co-treatment group, a finding not seen for either AR or PSA. CONCLUSION At concentrations associated with gene re-expression, the DNA demethylating agent 5-AZAC and the HDAC inhibitor TSA co-operate to induce apoptosis in prostate cancer cell-lines. Increased apoptosis in the co-treatment group was associated with marked re-expression of ERbeta, raising the possibility of further targeting of prostate cancer cells with ERbeta-selective agents.
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Abstract
Marijuana is the most commonly used illicit drug while its abuse and dependence has an increasing prevalence among the young population. Marijuana smoking affects the circulatory system triggering various cardiovascular events. Of note, recent case reports indicate a possible association with atrial fibrillation (AF). In this article, we provide a brief systematic review of all reported cases implicating marijuana smoking in AF development and we concisely discuss the potential underlying mechanisms as well as the clinical implications of this emerging association.
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Zhao XG, Zheng Y, Liang JM, Chan QCC, Yang XF, Li G, Yang ES. In vivo tumor detection on rabbit with biopsy needle as MRE driver. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2008; 2008:121-124. [PMID: 19162608 DOI: 10.1109/iembs.2008.4649105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Magnetic Resonance Elastography (MRE) is a phase contrast imaging technique to quantitatively measure the elasticity of tissues. Typically, the oscillating driver is placed on the surface of objects to generate shear waves. When it is applied to detect tumors in deep location, the depth penetration of the wave is limited by attenuation and the biopsy procedure has to be performed separately. In this study, we describe a method using biopsy needle as the MRE driver to produce shear waves in tissues. We made comparison between the MRE acquisitions obtained with biopsy needle and surface drivers. Because the well-defined propagation wave pattern reduces the error in wavelength calculation, the acquisitions of biopsy needle driver shows better homogeneity in stiffness map. We also performed the experiment with the biopsy needle for in vivo tumor detection in rabbits. This study demonstrates that the biopsy needle driver is more effective than the surface driver for accurately measuring the stiffness and location of the tumor.
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Suri HS, Li G, Gajic O. Epidemiology of Acute Respiratory Failure and Mechanical Ventilation. Intensive Care Med 2008. [PMCID: PMC7121586 DOI: 10.1007/978-0-387-77383-4_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Acute respiratory failure, and the need for mechanical ventilation, remains one of the most common reasons for admission to the intensive care unit (ICU). The burden of acute respiratory failure is high in terms of mortality and morbidity as well as the cost of its principal treatment, mechanical ventilation. Very few epidemiologic studies have evaluated the prevalence and outcome of acute respiratory failure and mechanical ventilation in general. Most of the published literature has focused on specific forms of acute respiratory failure, particularly acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). In this chapter, we provide a brief review of the pathophysiology of acute respiratory failure, its definition and classification, and then present the incidence and outcomes of specific forms of acute respiratory failure from epidemiologic studies.
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Duggan D, Zheng SL, Knowlton M, Benitez D, Dimitrov L, Wiklund F, Robbins C, Isaacs SD, Cheng Y, Li G, Sun J, Chang BL, Marovich L, Wiley KE, Balter K, Stattin P, Adami HO, Gielzak M, Yan G, Sauvageot J, Liu W, Kim JW, Bleecker ER, Meyers DA, Trock BJ, Partin AW, Walsh PC, Isaacs WB, Gronberg H, Xu J, Carpten JD. Two Genome-wide Association Studies of Aggressive Prostate Cancer Implicate Putative Prostate Tumor Suppressor Gene DAB2IP. J Natl Cancer Inst 2007; 99:1836-44. [DOI: 10.1093/jnci/djm250] [Citation(s) in RCA: 217] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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1157
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Schwartz JH, Li G, Yang Q, Suri V, Ross JJ, Alexander EA. Role of SNAREs and H+-ATPase in the targeting of proton pump-coated vesicles to collecting duct cell apical membrane. Kidney Int 2007; 72:1310-5. [PMID: 17805241 DOI: 10.1038/sj.ki.5002500] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recycling of H(+)-ATPase to the apical plasma membrane, mediated by vesicular exocytosis and endocytosis, is an important mechanism for controlling H(+) secretion by the collecting duct. We hypothesized that SNAREs (soluble N-ethylmaleimide-sensitive factor attachment proteins) may be involved in the targeting of H(+)-ATPase-coated vesicles. Using a tissue culture model of collecting duct H(+) secretory cells (inner medullary collecting duct (IMCD) cells), we demonstrated that they express the proteins required for SNARE-mediated exocytosis and form SNARE-fusion complexes upon stimulation of H(+)-ATPase exocytosis. Furthermore, exocytic amplification of apical H(+)-ATPase is sensitive to clostridial toxins that cleave SNAREs and thereby inhibit secretion. Thus, SNAREs are critical for H(+)-ATPase cycling to the plasma membrane. The process in IMCD cells has a feature distinct from that of neuronal cells: the SNARE complex includes and requires the vesicular cargo (H(+)-ATPase) for targeting. Using chimeras and truncations of syntaxin 1, we demonstrated that there is a specific cassette within the syntaxin 1 H3 domain that mediates binding of the SNAREs and a second distinct H3 region that binds H(+)-ATPase. Utilizing point mutations of the B1 subunit of the H(+)-ATPase, we document that this subunit contains specific targeting information for the H(+)-ATPase itself. In addition, we found that Munc-18-2, a regulator of exocytosis, plays a multifunctional role in this system: it regulates SNARE complex formation and the affinity of syntaxin 1 for H(+)-ATPase.
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Zhao XG, Zheng Y, Chan QCC, Yang XF, Li G, Yang ES. Biopsy needle as MRE driver for tumor detection. ACTA ACUST UNITED AC 2007; 2007:2050-2. [PMID: 18002389 DOI: 10.1109/iembs.2007.4352723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Magnetic Resonance Elastography (MRE) is a phase contrast imaging technique to quantitatively measure the elasticity of tissues. Typically, an oscillating driver is placed on the surface to generate the shear waves. The depth penetration of the wave is limited by attenuation and the biopsy procedure has to be done separately. In this study, we use a biopsy needle as the driver to detect the 15% porcine gel inclusion in a 10% porcine gel phantom which simulates a tumor in tissues. We also perform the experiment with the biopsy needle for in-vivo tumor detection in rabbits. It is shown that the biopsy needle driver can accurately measure the stiffness and location of the tumor.
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1159
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Ablikim M, Bai JZ, Ban Y, Cai X, Chen HF, Chen HS, Chen HX, Chen JC, Chen J, Chen YB, Chu YP, Dai YS, Diao LY, Deng ZY, Dong QF, Du SX, Fang J, Fang SS, Fu CD, Gao CS, Gao YN, Gu SD, Gu YT, Guo YN, Guo ZJ, Harris FA, He KL, He M, Heng YK, Hou J, Hu HM, Hu JH, Hu T, Huang GS, Huang XT, Ji XB, Jiang XS, Jiang XY, Jiao JB, Jin DP, Jin S, Lai YF, Li G, Li HB, Li J, Li RY, Li SM, Li WD, Li WG, Li XL, Li XN, Li XQ, Liang YF, Liao HB, Liu BJ, Liu CX, Liu F, Liu F, Liu HH, Liu HM, Liu J, Liu JB, Liu JP, Liu J, Liu Q, Liu RG, Liu ZA, Lou YC, Lu F, Lu GR, Lu JG, Luo CL, Ma FC, Ma HL, Ma LL, Ma QM, Mao ZP, Mo XH, Nie J, Olsen SL, Ping RG, Qi ND, Qin H, Qiu JF, Ren ZY, Rong G, Ruan XD, Shan LY, Shang L, Shen CP, Shen DL, Shen XY, Sheng HY, Sun HS, Sun SS, Sun YZ, Sun ZJ, Tang X, Tong GL, Varner GS, Wang DY, Wang L, Wang LL, Wang LS, Wang M, Wang P, Wang PL, Wang WF, Wang YF, Wang Z, Wang ZY, Wang Z, Wei CL, Wei DH, Weng Y, Wu N, Xia XM, Xie XX, Xu GF, Xu XP, Xu Y, Yan ML, Yang HX, Yang YX, Ye MH, Ye YX, Yu GW, Yuan CZ, Yuan Y, Zang SL, Zeng Y, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HQ, Zhang HY, Zhang JW, Zhang JY, Zhang SH, Zhang XY, Zhang Y, Zhang ZX, Zhang ZP, Zhao DX, Zhao JW, Zhao MG, Zhao PP, Zhao WR, Zhao ZG, Zheng HQ, Zheng JP, Zheng ZP, Zhou L, Zhu KJ, Zhu QM, Zhu YC, Zhu YS, Zhu ZA, Zhuang BA, Zhuang XA, Zou BS. Measurements ofJ/ψandψ(2S)decays intoΛΛ¯π0andΛΛ¯η. Int J Clin Exp Med 2007. [DOI: 10.1103/physrevd.76.092003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abstract
Background. RNA interference, a conserved mechanism in which a sequence‐specific gene‐silencing process is mediated by small interfering RNA (siRNA), is a promising method of gene therapy in treating a variety of viral diseases. Aim. To investigate the antiviral effects of siRNA on herpes simplex virus type 1 (HSV‐1) replication in Vero cells. Methods. The antiviral effects of siRNA duplexes targeting the VP16 and DNA polymerase genes of HSV‐1 were evaluated by yield‐reduction and plaque‐reduction assays. The effect of siRNA on the expression of target genes was measured by real‐time quantitative reverse transcription PCR. Results. Two siRNA duplexes (siRNA‐1, targeting VP16, and siRNA‐4, targeting DNA polymerase), were found to be highly effective in inhibiting HSV‐1 replication. siRNA‐1 and siRNA‐4 reduced HSV‐1 replication by around 2 log10 and 1 log10 in the yield‐‐reduction assay and by ∼85% and ∼70% in the plaque‐reduction assay, respectively. Significant decreases in the mRNA level of VP16 and DNA polymerase genes were detected after viral infection in the Vero cells pretreated with siRNA‐1 and siRNA‐4, respectively. Conclusion. These results indicate that siRNA can potently inhibit HSV‐1 replication in vitro, suggesting that siRNA‐based antiviral therapy may be a potential effective therapeutic alternative for patients with HSV‐1 infection.
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Li G, Guion P, Ning H, Citrin D, Xie H, Capala J, Arora B, Camphausen K, Singh A, Miller R. A Pancreas Motion Study Using Automatic Image Segmentation of Time-Resolved, Single-Slice MR Images. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.2289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Miller R, Ning H, Justus B, Huston A, Li G, Chang J, Capala J, Xie H, Citrin D, Camphausen K. Use of an Optical Fiber Dosimeter to Measure Small Field Output Factors in Stereotactic Radiosurgery. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.1990] [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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1163
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Tang F, Qu L, Xu Y, Ma R, Chen S, Li G. Practical Synthesis of Structurally Important Spirodiamine Templates. SYNTHETIC COMMUN 2007. [DOI: 10.1080/00397910701571599] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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1164
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Li G, Hu WZ, Dong J, Qian D, Hsieh D, Hasan MZ, Morosan E, Cava RJ, Wang NL. Anomalous Metallic State of Cu0.07TiSe2: an optical spectroscopy study. PHYSICAL REVIEW LETTERS 2007; 99:167002. [PMID: 17995282 DOI: 10.1103/physrevlett.99.167002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Revised: 06/30/2007] [Indexed: 05/25/2023]
Abstract
We report an optical spectroscopy study on the newly discovered superconductor Cu0.07TiSe2. Consistent with the development from a semimetal or semiconductor with a very small indirect energy gap upon doping TiSe2, it is found that the compound has a low carrier density. Most remarkably, the study reveals a substantial shift of the screened plasma edge in reflectance towards high energy with decreasing temperature. This phenomenon, rarely seen in metals, indicates either a sizable increase of the conducting carrier concentration or/and a decrease of the effective mass of carriers with reducing temperature. We attribute the shift primarily to the latter effect.
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larrat B, Chan QC, Yang XF, Li G, Yang ES, Fink M, Sinkus R. 8C-6 Anisotropic Viscoelastic Properties of the Corpus Callosum - Application of High-Resolution 3D MR-Elastography to an Alzheimer Mouse Model. ACTA ACUST UNITED AC 2007. [DOI: 10.1109/ultsym.2007.175] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Li G, Sokal I, Quinn JF, Leverenz JB, Brodey M, Schellenberg GD, Kaye JA, Raskind MA, Zhang J, Peskind ER, Montine TJ. CSF tau/Abeta42 ratio for increased risk of mild cognitive impairment: a follow-up study. Neurology 2007; 69:631-9. [PMID: 17698783 DOI: 10.1212/01.wnl.0000267428.62582.aa] [Citation(s) in RCA: 195] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Processes of Alzheimer disease (AD) likely begin years prior to the onset of cognitive impairment (latent AD), progress though a prodromal phase of mild cognitive impairment (MCI), and culminate in dementia. While many studies have evaluated CSF tau and Abeta(42) as biomarkers of the dementia or prodromal stages of AD, we are unaware of any study to evaluate these potential CSF biomarkers of latent AD. METHODS We determined the ratio of CSF tau/Abeta(42) (T/Abeta) using Luminex reagents in 129 control individuals that spanned from 21 to 100 years of age; for comparison we included patients with MCI (n = 12), probable AD (n = 21), or other neurodegenerative diseases (n = 12). RESULTS We identified 16% of the control group with abnormally elevated CSF T/Abeta; all were 53 years or older. Using age-matched controls with normal CSF T/Abeta we showed that the high CSF T/Abeta subgroup of controls had significantly increased frequency of the epsilon4 allele of the apolipoprotein E gene and significantly increased risk of conversion to MCI during follow-up of up to 42 months suggesting that they had latent AD at the time of lumbar puncture. CONCLUSIONS These generally applicable methods establish cutoff values to identify control individuals at increased risk of conversion to mild cognitive impairment which may be useful to people weighing the risk-benefit ratio of new preventive therapeutics and to researchers striving to enrich clinical trial populations with people with latent Alzheimer disease.
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Fu JF, Shi JY, Zhao WL, Li G, Pan Q, Li JM, Hu J, Shen ZX, Jin J, Chen FY, Chen SJ. MassARRAY assay: a more accurate method for JAK2V617F mutation detection in Chinese patients with myeloproliferative disorders. Leukemia 2007; 22:660-3. [PMID: 17728780 DOI: 10.1038/sj.leu.2404931] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
MESH Headings
- Biomarkers, Tumor/genetics
- China/epidemiology
- Female
- Gene Frequency
- Genotype
- Humans
- Hypereosinophilic Syndrome/enzymology
- Hypereosinophilic Syndrome/epidemiology
- Hypereosinophilic Syndrome/genetics
- Janus Kinase 2/genetics
- Leukemia, Myeloid/enzymology
- Leukemia, Myeloid/epidemiology
- Leukemia, Myeloid/genetics
- Male
- Mutation, Missense
- Myeloproliferative Disorders/enzymology
- Myeloproliferative Disorders/epidemiology
- Myeloproliferative Disorders/genetics
- Oligonucleotide Array Sequence Analysis/methods
- Point Mutation
- Polymerase Chain Reaction/methods
- Polymorphism, Restriction Fragment Length
- Polymorphism, Single Nucleotide
- Sensitivity and Specificity
- Sequence Analysis, DNA
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
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1168
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Li G, Larson EB, Sonnen JA, Shofer JB, Petrie EC, Schantz A, Peskind ER, Raskind MA, Breitner JCS, Montine TJ. Statin therapy is associated with reduced neuropathologic changes of Alzheimer disease. Neurology 2007; 69:878-85. [PMID: 17724290 DOI: 10.1212/01.wnl.0000277657.95487.1c] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Treatment with 3-hydroxy-3-methylglutaryl-coenzyme-A reductase inhibitors ("statins") has been associated in some epidemiologic studies with reduced risk of Alzheimer disease (AD). However, direct evidence of statin effects on neuropathologic markers of AD is lacking. We investigated whether antecedent statin exposure is associated with neuritic plaque (NP) or neurofibrillary tangle (NFT) burden in a population-based sample of human subjects. METHODS Brain autopsies were performed on 110 subjects, ages 65 to 79 years, who were cognitively normal at enrollment into the Adult Changes in Thought Study. Neuropathologic findings were compared between statin users with > or =3 prescriptions of > or =15 pills of simvastatin, pravastatin, lovastatin, or atorvastatin vs nonusers, based on pharmacy dispensing records. RESULTS After controlling for age at death, gender, cognitive function at study entry, brain weight, and presence of cerebral microvascular lesions, the odds ratio (OR) for each unit increase in Braak NFT stage in statin users vs nonusers was 0.44 (95% CI: 0.20 to 0.95). The OR for each unit increase in Consortium to Establish a Registry for Alzheimer's Disease (CERAD) staging of NPs did not deviate significantly from unity (OR 0.69; 95% CI: 0.32 to 1.52). However, the risk for typical AD pathology (Braak stage > or = IV and CERAD rating > or = moderate) was reduced in statin users (OR 0.20; 95% CI: 0.05 to 0.86). CONCLUSIONS These findings demonstrate an association between antecedent statin use and neurofibrillary tangle burden at autopsy. Additional study is needed to examine whether statin use may be causally related to decreased development of Alzheimer disease-related neuropathologic changes.
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Li G, Satyamoorthy K, Herlyn M. Dynamics of cell interactions and communications during melanoma development. CRITICAL REVIEWS IN ORAL BIOLOGY AND MEDICINE : AN OFFICIAL PUBLICATION OF THE AMERICAN ASSOCIATION OF ORAL BIOLOGISTS 2007; 13:62-70. [PMID: 12097238 DOI: 10.1177/154411130201300107] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Melanoma development not only involves genetic and epigenetic changes that take place within the cell, but also involves processes determined collectively by micro-environmental factors, including cell-cell interactions and communications. During the transition from normal cells to benign and malignant lesions, and subsequently to metastatic cancer, stepwise changes in intercellular communications provide tumor cells with the ability to overcome cell-cell adhesion and micro-environmental controls from the host and to invade surrounding tissues and disperse to distant locations. Cadherins are major cell-cell adhesion molecules involved in the development and maintenance of skin. E-cadherin expressed in normal melanocytes mediates growth and invasion control by keratinocytes. Progressive loss of E-cadherin and gain of N-cadherin during melanoma development not only free melanoma cells from control by keratinocytes, but also provide new adhesion properties, resulting in switched partnerships with fibroblasts and vascular endothelial cells. The cadherin subtype switching also dictates gap junctional specificity in melanocytic cells during tumor development. This selective intercellular communication may contribute to the regulation of cell growth, differentiation, apoptosis, and migration of melanocytic cells in both physiologic and pathologic conditions. Abnormal up-regulation of the immunoglobin repeat-containing cell adhesion molecules Mel-CAM and L1-CAM potentiates invasion and migration of melanoma. Thus, abnormal expression of intercellular adhesion receptors and dysregulated intercellular communication underlies melanoma development and progression.
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Zheng Y, Li G, Chen M, Chan QCC, Hu SG, Zhao XN, Ehman RL, Lam EY, Yang ES. Magnetic Resonance Elastography with Twin Pneumatic Drivers for Wave Compensation. ACTA ACUST UNITED AC 2007; 2007:2611-3. [DOI: 10.1109/iembs.2007.4352864] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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1171
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Li G, Qi XP, Wu XY, Liu FK, Xu Z, Chen C, Yang XD, Sun Z, Li JS. Verapamil modulates LPS-induced cytokine production via inhibition of NF-kappa B activation in the liver. Inflamm Res 2007; 55:108-13. [PMID: 16673153 DOI: 10.1007/s00011-005-0060-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
OBJECTIVE To investigate the effect of verapamil on Lipopolysaccharide (LPS)-induced cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-10 (IL-10)] and nuclear factor kappa B (NF-kappa B) in the liver. METHODS AND MATERIALS Adult male Sprague-Dawley rats were randomly divided into seven groups of eight rats each: control rats treated with saline (0.9 % NaCl); rats treated with saline and then challenged intraperitoneally with LPS (10 mg/kg); rats treated intraperitoneally with different levels of verapamil (1, 2.5, 5, 10 mg/kg) and then challenged with LPS (10 mg/kg); and rats treated only with verapamil (10 mg/kg). TNF-alpha, IL-6, IL-10 and NF-kappa B in the liver tissues were investigated as well as the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) one hour after LPS injection. RESULTS LPS alone stimulated production of TNF-alpha, IL-6 and IL-10, and activated NF-kappa B in the liver. Pretreatment with verapamil before LPS challenge reduced acute liver injury, down-regulated production of LPS-induced pro-inflammatory cytokines (TNF-alpha and IL-6), up-regulated production of anti-inflammatory cytokines (IL-10) and inhibited NF-kappa B activation in the liver in a dose-dependent manner. CONCLUSION Verapamil can attenuate acute liver injury by down-regulating the production of TNF-alpha and IL-6 and up-regulating IL-10 in the liver, possibly via inhibition of NF-kappa B.
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Li G, Hu WZ, Qian D, Hsieh D, Hasan MZ, Morosan E, Cava RJ, Wang NL. Semimetal-to-semimetal charge density wave transition in 1T-TiSe(2). PHYSICAL REVIEW LETTERS 2007; 99:027404. [PMID: 17678260 DOI: 10.1103/physrevlett.99.027404] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Indexed: 05/16/2023]
Abstract
We report an infrared study on 1T-TiSe(2), the parent compound of the newly discovered superconductor Cu(x)TiSe(2). Previous studies of this compound have not conclusively resolved whether it is a semimetal or a semiconductor-information that is important in determining the origin of its unconventional charge density wave (CDW) transition. Here we present optical spectroscopy results that clearly reveal that the compound is metallic in both the high-temperature normal phase and the low-temperature CDW phase. The carrier scattering rate is dramatically different in the normal and CDW phases and the carrier density is found to change with temperature. We conclude that the observed properties can be explained within the scenario of an Overhauser-type CDW mechanism.
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Ablikim M, Bai JZ, Ban Y, Cai X, Chen HF, Chen HS, Chen HX, Chen JC, Chen J, Chen YB, Chu YP, Dai YS, Diao LY, Deng ZY, Dong QF, Du SX, Fang J, Fang SS, Fu CD, Gao CS, Gao YN, Gu SD, Gu YT, Guo YN, Guo ZJ, Harris FA, He KL, He M, Heng YK, Hou J, Hu HM, Hu JH, Hu T, Huang GS, Huang XT, Ji XB, Jiang XS, Jiang XY, Jiao JB, Jin DP, Jin S, Lai YF, Li G, Li HB, Li J, Li RY, Li SM, Li WD, Li WG, Li XL, Li XN, Li XQ, Liang YF, Liao HB, Liu BJ, Liu CX, Liu F, Liu F, Liu HH, Liu HM, Liu J, Liu JB, Liu JP, Liu JLQ, Liu RG, Liu ZA, Lou YC, Lu F, Lu GR, Lu JG, Luo CL, Ma FC, Ma HL, Ma LL, Ma QM, Mao ZP, Mo XH, Nie J, Olsen SL, Ping RG, Qi ND, Qin H, Qiu JF, Ren ZY, Rong G, Ruan XD, Shan LY, Shang L, Shen CP, Shen DL, Shen XY, Sheng HY, Sun HS, Sun SS, Sun YZ, Sun ZJ, Tang X, Tong GL, Varner GS, Wang DY, Wang L, Wang LL, Wang LS, Wang M, Wang P, Wang PL, Wang YF, Wang Z, Wang ZY, Wang Z, Wei CL, Wei DH, Weng Y, Wu N, Xia XM, Xie XX, Xu GF, Xu XP, Xu Y, Yan ML, Yang HX, Yang YX, Ye MH, Ye YX, Yu GW, Yuan CZ, Yuan Y, Zang SL, Zeng Y, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HQ, Zhang HY, Zhang JW, Zhang JY, Zhang SH, Zhang XY, Zhang Y, Zhang ZX, Zhang ZP, Zhao DX, Zhao JW, Zhao MG, Zhao PP, Zhao WR, Zhao ZG, Zheng HQ, Zheng JP, Zheng ZP, Zhou L, Zhu KJ, Zhu QM, Zhu YC, Zhu YS, Zhu ZA, Zhuang BA, Zhuang XA, Zou BS. Measurement of psi2S radiative decays. PHYSICAL REVIEW LETTERS 2007; 99:011802. [PMID: 17678148 DOI: 10.1103/physrevlett.99.011802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Indexed: 05/16/2023]
Abstract
Using 14 x 10(6) psi(2S) events accumulated at the BESII detector, we report first measurements of branching fractions or upper limits for psi(2S) decays into gammapp, gamma2(pi+pi-), gammaKS0K+pi-+c.c., gammaK+K-pi+pi-, gammaK*0K-pi++c.c., gammaK*0K*0, gammapi+pi-pp, gamma2(K+K-), gamma3(pi+pi-), and gamma2(pi+pi-)K+K- with the invariant mass of hadrons below 2.9 GeV/c2. We also report branching fractions of psi(2S) decays into 2(pi+pi-)pi0, omegapi+pi-, omegaf2(1270), b1+/-pi-/+, and pi02(pi+pi-)K+K-.
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Peretz M, Bogin O, Tel-Or S, Cohen A, Li G, Chen JS, Burstein Y. Molecular cloning, nucleotide sequencing, and expression of genes encoding alcohol dehydrogenases from the thermophile Thermoanaerobacter brockii and the mesophile Clostridium beijerinckii. Anaerobe 2007; 3:259-70. [PMID: 16887600 DOI: 10.1006/anae.1997.0083] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/1996] [Accepted: 03/27/1997] [Indexed: 11/22/2022]
Abstract
Proteins play a pivotal role in thermophily. Comparing the molecular properties of homologous proteins from thermophilic and mesophilic bacteria is important for understanding the mechanisms of microbial adaptation to extreme environments. The thermophile Thermoanaerobacter (Thermoanaerobium) brockii and the mesophile Clostridium beijerinckii contain an NADP(H)-linked, zinc-containing secondary alcohol dehydrogenase (TBADH and CBADH) showing a similarly broad substrate range. The structural genes encoding the TBADH and the CBADH were cloned, sequenced, and highly expressed in Escherichia coli. The coding sequences of the TB adh and the CB adh genes are, respectively, 1056 and 1053 nucleotides long. The TB adh gene encoded an amino acid sequence identical to that of the purified TBADH. Alignment of the deduced amino acid sequences of the TB and CB adh genes showed a 76% identity and a 86% similarity, and the two genes had a similar preference for codons with A or T in the third position. Multiple sequence alignment of ADHs from different sources revealed that two (Cys-46 and His-67) of the three ligands for the catalytic Zn atom of the horse-liver ADH are preserved in TBADH and CBADH. Both the TBADH and CBADH were homotetramers. The substrate specificities and thermostabilities of the TBADH and CBADH expressed inE. coli were identical to those of the enzymes isolated from T. brockii and C. beijerinckii, respectively. A comparison of the amino acid composition of the two ADHs suggests that the presence of eight additional proline residues in TBADH than in CBADH and the exchange of hydrophilic and large hydrophobic residues in CBADH for the small hydrophobic amino acids Pro, Ala, and Val in TBADH might contribute to the higher thermostability of the T. brockii enzyme.
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Li G, Zhang Y, Cheng KY, Scarpace PJ. Lean rats with hypothalamic pro-opiomelanocortin overexpression exhibit greater diet-induced obesity and impaired central melanocortin responsiveness. Diabetologia 2007; 50:1490-9. [PMID: 17505816 DOI: 10.1007/s00125-007-0685-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2007] [Accepted: 03/15/2007] [Indexed: 11/26/2022]
Abstract
AIMS/HYPOTHESIS Central pro-opiomelanocortin (Pomc) gene therapy ameliorates genetic- or age-related obesity. We hypothesised that this treatment would delay or prevent dietary obesity in young, lean rats. MATERIALS AND METHODS Recombinant adeno-associated virus encoding Pomc (rAAV-Pomc) was delivered bilaterally into the basomedial hypothalamus of lean rats for 42 days. Food intake, body weight, serum hormones, brown adipose tissue (BAT) uncoupling protein 1 (UCP1) and mRNA levels of hypothalamic neuropeptides and melanocortin receptors were assessed. Beginning on day 43, half of the rats remained on chow while the others received a high-fat diet for 89 days. We examined energy balance and responsiveness to the melanocortin agonist melanotan II (MTII) or the antagonist SHU9119. RESULTS Pomc gene delivery produced elevated hypothalamic Pomc mRNA (fourfold) and alpha-melanocyte-stimulating hormone levels in the arcuate nucleus (twofold). Food intake and body weight were not altered by rAAV-Pomc in rats fed standard-chow. In rAAV-Pomc rats at day 42, perirenal fat and serum leptin decreased but overall visceral adiposity did not; expression of the hypothalamic agouti-related protein (Agrp) mRNA was elevated, whereas expression of melanocortin 3 and 4 receptor mRNA was reduced; BAT UCP1 protein increased nearly fourfold. The rAAV-Pomc rats fed the high-fat diet consumed more energy and gained more body weight compared with chow- or high-fat-fed controls that did not receive Pomc gene delivery. The anorexic response to MTII was impaired, whereas the orexigenic effect of SHU9119 was enhanced by rAAV-Pomc pretreatment. CONCLUSIONS/INTERPRETATION Delivery of the Pomc gene alters energy homeostasis in lean rats, predisposing them to diet-induced obesity. Diminished hypothalamic melanocortin receptors, increased Agrp expression, and potential rewiring of brain circuits may underlie the exacerbated obesity.
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