651
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Cao Z, Wang W, Xiao X, Chen K, Liang X, Yu D. High-Level Expression and Purification of an Analgesic Peptide from Buthus martensii Karch. Protein Pept Lett 2007; 14:247-51. [PMID: 17346228 DOI: 10.2174/092986607780090883] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BmK AngM1, a scorpion peptide isolated from Buthus martensii Karch was reported to exhibit potential analgesic effect. But the relative low content of this toxin in crude venom limits its further characterization. In this study, we constructed an expression vector and transformed into E.coli. The BmK AngM1 was expressed as a fusion protein in the soluble fraction and was purified by Nickel affinity chromatography. Subsequently, the purified fusion protein was cleaved by enterokinase and was further purified by reverse-phase HPLC. We purified 25 mg recombinant BmK AngM1 (rBmK AngM1) from 1 L bacterial culture. The molecular weight of rBmK AngM1 determined by ESI-MS was 7240.4 Da which was the expected size for correctly processed. Analgesic bioassay studies of rBmK AngM1 exhibited its potential analgesic effect comparable to that of the natural BmK AngM1 peptide.
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652
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Chen HY, Einstein DR, Chen K, Vesely I. Computational modeling of vascular clamping: a step toward simulating surgery. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2006:302-3. [PMID: 17282173 DOI: 10.1109/iembs.2005.1616404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The objective of this study was to simulate clamping of the aorta. It is computationally demanding and involves contact between clamp and aorta, large deformations, and fluid-structure interactions (FSI). Models of the aortic root and clamp were created and solve in ADINA, a Finite Element Analysis package. The tissue model was created using a non-linear material. Fluid-structure interactions (FSI) were modeled. The deformation profile of the simulated aorta matched well with that of the real tissue. Clamping of a fluid-filled pressurized aorta, an important first step towards simulating of surgical procedures, was successfully modeled. The simulation was validated by clamping experiments. The modeling techniques developed are also applicable to pre-operative planning of cardiovascular surgery.
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653
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Limmer J, Schönamsgruber E, Chen K, Lush C, Burns C, Ellero C, Kesty N, Herrmann K. Gewichtsabnahme adipöser Patienten nach Pramlintide-Gabe ist mit anhaltend verminderter Kalorienaufnahme verbunden. DIABETOL STOFFWECHS 2007. [DOI: 10.1055/s-2007-982420] [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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654
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Chen K, Yu C, Chen P, Cheng A. 485 POSTER The inhibition of P13K/Akt pathway as a major molecular determinant of bortezomib-induced apoptosis in hepatocellular carcinoma cells. EJC Suppl 2006. [DOI: 10.1016/s1359-6349(06)70490-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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655
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Fawaz W, Chen K. OPN09-04: SSTF: A 'Shortest Setup Time First' Optical Connections Setup Management Approach with Quantifiable Success Rate. ACTA ACUST UNITED AC 2006. [DOI: 10.1109/glocom.2006.409] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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656
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Knorr C, Beck J, Beuermann C, Chen K, Ding N, Gatphayak K, Huang LS, Laenoi W, Brenig B. Chromosomal assignment of porcine oncogenic and apoptopic genes CACNA2D2, TUSC4, ATP2A1, COL1A1, TAC1, BAK1 and CASP9. Anim Genet 2006; 37:523-5. [PMID: 16978189 DOI: 10.1111/j.1365-2052.2006.01507.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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657
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Yan J, Ling S, Liu H, Zhang H, Song X, Xiu B, Chen K, Wang G, Zhu C. Induction of strong cytotoxic T-lymphocyte responses to hepatitis C virus with recombinant poly-epitope in BALB/c mice. Viral Immunol 2006; 19:64-73. [PMID: 16553551 DOI: 10.1089/vim.2006.19.64] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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658
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Chen K, Cole J, Conger C, Draskovic J, Lohr M, Klein K, Scheidemantel T, Schiffer P. Packing grains by thermal cycling. Nature 2006; 442:257. [PMID: 16855580 DOI: 10.1038/442257a] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2006] [Accepted: 06/15/2006] [Indexed: 11/09/2022]
Abstract
A long-standing problem in managing the behaviour of a collection of solid grains concerns the nature of the grain packing, a property that is typically controlled by how the grains are poured or shaken. Here we show that a systematic and controllable increase in granular packing can be induced by simply raising and then lowering the temperature, without the input of mechanical energy. This thermal processing may have important practical implications for the handling and storage of granular materials.
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659
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DelParigi A, Chen K, Salbe AD, Hill JO, Wing RR, Reiman EM, Tataranni PA. Successful dieters have increased neural activity in cortical areas involved in the control of behavior. Int J Obes (Lond) 2006; 31:440-8. [PMID: 16819526 DOI: 10.1038/sj.ijo.0803431] [Citation(s) in RCA: 182] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To investigate whether dietary restraint, a landmark of successful dieting, is associated with specific patterns of brain responses to the sensory experience of food and meal consumption. DESIGN AND SUBJECTS Cross-sectional study of the brain's response to the sensory experience of food and meal consumption in nine successful dieters (age: 38+/-7 years, body fat (%): 28+/-3) and 20 non-dieters (age: 31+/-9 years, body fat (%): 33+/-9), all women. MEASUREMENTS Changes in brain activity in response to the sensory experience of food and meal consumption were assessed by using positron emission tomography and (15)O water as a radiotracer. Body fatness was assessed by dual X-ray absorptiometry. Subjective ratings of hunger and fullness were measured by visual analogue scale. Dietary restraint, disinhibition and hunger were assessed by the Three Factor Eating Questionnaire. RESULTS Successful dieters had a significantly higher level of dietary restraint compared to non-dieters. In response to meal consumption, successful dieters had a greater activation in the dorsal prefrontal cortex (DPFC), dorsal striatum and anterior cerebellar lobe as compared to non-dieters. In response to the same stimulation, the orbitofrontal cortex (OFC) was significantly more activated in non-dieters as compared to successful dieters. Dietary restraint was positively correlated with the response in the DPFC and negatively with the response in the OFC. The responses in the DPFC and OFC were negatively intercorrelated. CONCLUSION Cortical areas involved in controlling inappropriate behavioral responses, such as the DPFC, are particularly activated in successful dieters in response to meal consumption. The association between the degree of dietary restraint and the coordinated neural changes in the DPFC and OFC raises the possibility that cognitive control of food intake is achieved by modulating neural circuits controlling food reward.
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660
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Chen K, Stone MB, Barry R, Lohr M, McConville W, Klein K, Sheu BL, Morss AJ, Scheidemantel T, Schiffer P. Flux through a hole from a shaken granular medium. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 74:011306. [PMID: 16907088 DOI: 10.1103/physreve.74.011306] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2005] [Revised: 04/26/2006] [Indexed: 05/11/2023]
Abstract
We have measured the flux of grains from a hole in the bottom of a shaken container of grains. We find that the peak velocity of the vibration, v max, controls the flux, i.e., the flux is nearly independent of the frequency and acceleration amplitude for a given value of v max. The flux decreases with increasing peak velocity and then becomes almost constant for the largest values of v max. The data at low peak velocity can be quantitatively described by a simple model, but the crossover to nearly constant flux at larger peak velocity suggests a regime in which the granular density near the container bottom is independent of the energy input to the system.
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661
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Yang C, Yu C, Chen K, Lin Z, Kuo S, Hwang T, Cheng A, Yang P. A phase II study of gefitinib as first line treatment for good performance advanced or metastatic non-small cell lung cancer in East Asian patients. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.7167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
7167 Background: Gefitinib is an effective treatment for chemotherapy-treated nonsmall cell lung cancer (NSCLC) in East Asian patients. There were only limited prospective studies on the use of gefitinib in chemonaive advanced or metastatic NSCLC patients. Methods: Eligibility included histological or cytological proven chemonaive stage IIIB/IV NSCLC, measurable disease, ECOG performance status of 0–2, good organ functions and candidate for platinum-based chemotherapy. Patients were treated with 250mg gefitinib per day. Tumor assessments were performed every two months by RECIST criteria. Responding patients were treated until progression. Patients with stable disease more than 2 months may continue treatment or shift to chemotherapy. The primary objective of this study was overall response rate of patients. Secondary objectives included 1-year progression-free survival, overall survival, and ancillary biomarker studies. Simon’s two-stage design was used to aim at a response rate more than 20%. Forty-four patients were planned in stage one and the study will be terminated if 5 or less patients responded to the treatment. A total of 106 patients are planned. Results: The planned interim analysis on the first 44 patients is reported here. There were 13 male and 31 female, median age was 63 (range 39–86), ECOG performance status of 0/1/2 were 0/40/4. 33 patients were nonsmokers. 39 patients had adenocarcinoma. The side effects of the treatment were mild and well accepted by patients. There were 24/9/10/1 patients with PR/SD/PD/NE. Overall response rate was 54.5% and disease control rate was 75%. The response rates for female / adenocarcinoma / nonsmoker were 58%/59%/61% respectively. The response rates for male / non-adenocarcinoma / smoker patients were 46%/20%/36%. The median time to progression for all patients was 6.3 months. Conclusions: Gefitinib is a very effective treatment for East Asian chemonaive advanced or metastatic NSCLC patients. Although the patients’ number was small, the response rates for patients with one unfavorable predictive factor were comparable to the response rates of patients receiving combination chemotherapy. The response rates and duration for 106 patients will be presented in the meeting. [Table: see text]
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662
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Del Parigi A, Chen K, Reiman EM. Is the brain representation of hunger normal in the Prader-Willi syndrome? Int J Obes (Lond) 2006; 31:390; author reply 390-1. [PMID: 16755279 DOI: 10.1038/sj.ijo.0803411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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663
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Huang J, Li T, Chen K, Wu J. An approach of encoding for prediction of splice sites using SVM. Biochimie 2006; 88:923-9. [PMID: 16626852 DOI: 10.1016/j.biochi.2006.03.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2004] [Revised: 03/06/2006] [Accepted: 03/09/2006] [Indexed: 11/18/2022]
Abstract
In splice sites prediction, the accuracy is lower than 90% though the sequences adjacent to the splice sites have a high conservation. In order to improve the prediction accuracy, much attention has been paid to the improvement of the performance of the algorithms used, and few used for solving the fundamental issues, namely, nucleotide encoding. In this paper, a predictor is constructed to predict the true and false splice sites for higher eukaryotes based on support vector machines (SVM). Four types of encoding, which were mono-nucleotide (MN) encoding, MN with frequency difference between the true sites and false sites (FDTF) encoding, Pair-wise nucleotides (PN) encoding and PN with FDTF encoding, were applied to generate the input for the SVM. The results showed that PN with FDTF encoding as input to SVM led to the most reliable recognition of splice sites and the accuracy for the prediction of true donor sites and false sites were 96.3%, 93.7%, respectively, and the accuracy for predicting of true acceptor sites and false sites were 94.0%, 93.2%, respectively.
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664
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Xu L, Chen J, Yu B, Dong W, Chen K, Luo H, Zhu Y. Effect of progesterone on calcium activated potassium currents and intracellular calcium in guinea pig colon myocytes. ACTA ACUST UNITED AC 2006; 27:475-82. [PMID: 16258592 DOI: 10.1358/mf.2005.27.7.896759] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
AIMS To study the effects of progesterone on contractile activity of smooth muscle strips and on ion currents and intracellular Ca2+ ([Ca2+]i) intensity in single colonic myocytes in guinea pig proximal colons. METHODS Strips and single cells were dissected from female guinea pig proximal colon. Contraction of strips through an isotonic transducer was assessed and the responsible currents to progesterone were recorded with EPC-9 amplifier in nystatin perforated whole-cell configuration. Detection of [Ca2+]i fluorescence loading fura-2 acetoxymethylester (fura-2/AM) was measured with confocal microscope. RESULTS Progesterone significantly inhibited contraction of guinea pig colon strips in a dose-dependent pattern. Inhibitory concentration 50 (IC50) of progesterone in longitudinal strips and circular strips was, respectively, 9.7 microM and 1.0 nM. Iberiotoxin (IbTX) partially blocked inhibition of progesterone in both oriented smooth muscle strips. Ca2+ activated K+ (K(Ca)) channel currents recorded by depolarizing pulse protocol were enhanced by progesterone to 138% +/- 13% (n = 9, p < 0.01), and to 143% +/- 12% (n = 8, p < 0.01) when perfused with 10 mcM onapristone. Progesterone reduced L-Ca2+ currents to 67% +/- 6% (n = 7, p < 0.01) and had no effect with 5 microM nicardipine in bath solution. [Ca2+]i fluorescence was reduced by progesterone to 75% +/- 12% (n = 8, p < 0.01). CONCLUSION Progesterone decreases the contraction of colonic smooth muscles by enhancing K(Ca) currents and reducing Ca2+ influx.
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665
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Cusmano-Ozog K, Chen K, Kwan A, Hudgins L. 336 BRACHYDACTYLY A1: IS IT A SINGLE CONDITION? J Investig Med 2006. [DOI: 10.2310/6650.2005.x0004.335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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666
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Cusmano-Ozog K, Chen K, Kwan A, Hudgins L. Brachydactyly A1: Is it a Single Condition? J Investig Med 2006. [DOI: 10.1177/108155890605401s219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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667
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Herrmann K, Chen K, Schönamsgruber E, Lush C, Limmer J, Burns C, Lutz K, Weyer C. Der Effekt von Pramlintide auf das Körpergewicht bei adipösen Probanden mit oder ohne Typ-2 Diabetes. DIABETOL STOFFWECHS 2006. [DOI: 10.1055/s-2006-943953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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668
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Chen K, Hasegawa-Johnson M, Cohen A, Borys S, Sung-Suk Kim, Cole J, Jeung-Yoon Choi. Prosody dependent speech recognition on radio news corpus of American English. ACTA ACUST UNITED AC 2006. [DOI: 10.1109/tsa.2005.853208] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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669
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Chen K, Chiou CF, Plauschinat CA, Frech F, Harper A, Dubois R. Patient satisfaction with antihypertensive therapy. J Hum Hypertens 2005; 19:793-9. [PMID: 15951740 DOI: 10.1038/sj.jhh.1001899] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The objective of the study was to assess factors associated with treatment satisfaction among patients receiving antihypertensive therapy. A weighted cross-sectional online survey was conducted with hypertensive patients participating in a chronic disease panel in the US. Patients on monotherapy with medications from the following classes were identified: ACE inhibitors (ACEIs), angiotensin receptor blockers (ARBs), beta blockers (BBs), calcium channel blockers (CCBs), and diuretics. The control group included patients without treatment. Pairwise comparisons between groups were conducted for factors that may affect patients' satisfaction. The study population had a mean age of 54.7+/-14.2 years and was 56.7% female. Participants with blood pressure (BP) controlled to JNC 7 guidelines were more satisfied with their medication than those with uncontrolled BP (90.3 vs 71.5%, P<0.05). Patients who had not experienced adverse events had higher satisfaction than patients experiencing adverse events (90.9 vs 75.8%, P<0.05). The most frequently self-reported adverse events were frequent urination, sexual dysfunction, and fatigue ranging from 7.0 to 9.6% across classes. The adverse event rates differed by class and were lowest among the ARBs. Patients on ARBs were the most likely to have switched from a previous antihypertensive class as compared to other classes (57.1% ARBs vs 49.8% ACEIs, 38.7% diuretics, 36.3% CCBs, and 31.7% BBs). Physician recommendation was the most common reason for switching. In conclusion, the ability to effectively treat hypertension depends upon a patient's satisfaction with antihypertensive therapy, which may be improved by achieving BP control and minimizing the occurrence of adverse events.
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670
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Johnson SC, Schmitz TW, Moritz CH, Meyerand ME, Rowley HA, Alexander AL, Hansen KW, Gleason CE, Carlsson CM, Ries ML, Asthana S, Chen K, Reiman EM, Alexander GE. Activation of brain regions vulnerable to Alzheimer's disease: the effect of mild cognitive impairment. Neurobiol Aging 2005; 27:1604-12. [PMID: 16226349 PMCID: PMC2627778 DOI: 10.1016/j.neurobiolaging.2005.09.017] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2005] [Revised: 07/29/2005] [Accepted: 09/08/2005] [Indexed: 11/25/2022]
Abstract
This study examined the functionality of the medial temporal lobe (MTL) and posterior cingulate (PC) in mild cognitive impairment amnestic type (MCI), a syndrome that puts patients at greater risk for developing Alzheimer disease (AD). Functional MRI (fMRI) was used to identify regions normally active during encoding of novel items and recognition of previously learned items in a reference group of 77 healthy young and middle-aged adults. The pattern of activation in this group guided further comparisons between 14 MCI subjects and 14 age-matched controls. The MCI patients exhibited less activity in the PC during recognition of previously learned items, and in the right hippocampus during encoding of novel items, despite comparable task performance to the controls. Reduced fMRI signal change in the MTL supports prior studies implicating the hippocampus for encoding new information. Reduced signal change in the PC converges with recent research on its role in recognition in normal adults as well as metabolic decline in people with genetic or cognitive risk for AD. Our results suggest that a change in function in the PC may account, in part, for memory recollection failure in AD.
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671
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Arasappan A, Njoroge FG, Chan TY, Bennett F, Bogen SL, Chen K, Gu H, Hong L, Jao E, Liu YT, Lovey RG, Parekh T, Pike RE, Pinto P, Santhanam B, Venkatraman S, Vaccaro H, Wang H, Yang X, Zhu Z, Mckittrick B, Saksena AK, Girijavallabhan V, Pichardo J, Butkiewicz N, Ingram R, Malcolm B, Prongay A, Yao N, Marten B, Madison V, Kemp S, Levy O, Lim-Wilby M, Tamura S, Ganguly AK. Hepatitis C virus NS3-4A serine protease inhibitors: SAR of moiety with improved potency. Bioorg Med Chem Lett 2005; 15:4180-4. [PMID: 16087332 DOI: 10.1016/j.bmcl.2005.06.091] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2005] [Revised: 06/28/2005] [Accepted: 06/29/2005] [Indexed: 11/22/2022]
Abstract
We have discovered that introduction of appropriate amino acid derivatives at P'2 position improved the binding potency of P3-capped alpha-ketoamide inhibitors of HCV NS3 serine protease. X-ray crystal structure of one of the inhibitors (43) bound to the protease revealed the importance of the P'2 moiety.
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672
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Jiang QT, Lee TKM, Chen K, Wong HL, Zheng JS, Giesy JP, Lo KKW, Yamashita N, Lam PKS. Human health risk assessment of organochlorines associated with fish consumption in a coastal city in China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2005; 136:155-65. [PMID: 15809117 DOI: 10.1016/j.envpol.2004.09.028] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2004] [Accepted: 09/17/2004] [Indexed: 05/20/2023]
Abstract
Food consumption is an important route of human exposure to organochlorines (OCs). In order to assess the potential health risks associated with these contaminants due to fish consumption, five species of fish were collected from a local market in Zhoushan City, an island in the East China Sea. Dioxin-like compounds, such as polychlorinated dibenzo-p-dioxins/ dibenzofurans, in the fish samples were screened by H4IIE-luc cell bioassay, and the concentrations of specific organochlorines were measured by gas chromatograph-electron capture detector (GC-ECD). The bioassay results indicated that concentrations of dioxin-like compounds in the fish samples were below detection limit (0.64 pg/mL). The concentrations of OC pesticides and PCBs ranged from 0.67 to 13 and 0.24 to 1.4 ng/g wet wt., respectively. Significantly, concentrations of p,p'-DDE in fish meat were comparatively high (average 3.9 ng/g wet wt.) compared with the other OC pesticides. The daily fish consumption, based on a dietary survey conducted among 160 local healthy residents, was determined to be 105 g/person. The relevant cancer benchmark concentrations of HCB, dieldrin, chlordane, DDTs and PCBs were 0.36, 0.04, 1.6, 1.7, and 0.29 ng/kg per day, respectively, based on the local diet. The hazard ratios (HRs), based on non-cancer endpoints were all less than 1.0, while the HRs based on cancer were greater than 1.0 for certain contaminants based on the 95th centile concentration in fish tissue.
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673
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Chen K, Wang R, Wen SY, Li J, Wang SQ. Relationship of P450 2C9 genetic polymorphisms in Chinese and the pharmacokinetics of tolbutamide. J Clin Pharm Ther 2005; 30:241-9. [PMID: 15896241 DOI: 10.1111/j.1365-2710.2005.00639.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: 11/30/2022]
Abstract
AIM To study the relationship between P450 2C9 genetic polymorphisms and the pharmacokinetics of tolbutamide in Chinese subjects. METHODS P450 2C9 genotype was determined by oligonucleotide microarray. Using tolbutamide as a probe of P450 2C9 activity, P450 2C9 phenotype in 20 healthy individuals expressing the P450 2C9*1/*1, *1/*3 and *3/*3 genotypes were evaluated. After administration of 500 mg tolbutamide, plasma and urine samples were collected from each subject over a 24-h period. The tolbutamide and its metabolites' concentrations in human plasma and urine were determined by solid-phase extraction and HPLC. RESULTS Tolbutamide AUC0-->infinity increased by 20 and 116%, and T(1/2) increased by 60 and 813%, respectively, in subjects expressing the P4502C9*1/*3 and *3/*3 genotypes compared with *1/*1 subjects. Reductions in tolbutamide oral clearance (68 and 11%) and formation clearance (39 and 3%) were detected in the *1/*3 and *3/*3 individuals, respectively, compared with */*1 subjects. CONCLUSION The P450 2C9 activity was significantly reduced in *1 heterozygotes compared with *1 homozygotes, and the metabolism of tolbutamide was more severely impaired in *3/*3 individuals compared with those expressing *1/*3. Using tolbutamide as a P450 2C9 probe, P450 2C9 genotype was the major determinant of P450 2C9 phenotype.
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674
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Sun Y, Li JY, He JS, Zhou LX, Chen K. Tissue microarray analysis of multiple gene expression in intestinal metaplasia, dysplasia and carcinoma of the stomach. Histopathology 2005; 46:505-14. [PMID: 15842632 DOI: 10.1111/j.1365-2559.2005.02111.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AIMS To study multiple gene expression patterns and their roles in the process of gastric carcinogenesis. METHODS AND RESULTS Using a high-throughput tissue microarray technique, 169 specimens from gastric carcinomas, precursor lesions and normal mucosa were immunostained on a series of tissue chips for p53, p21(WAF1/CIP1) cyclin E, Bcl-2, c-met and mucin 5AC expression. The overexpression of p53 was observed in 10.7% of low-grade dysplasia (LGD), 38.1% of high-grade dysplasia (HGD) and 39.6% of intestinal type gastric carcinoma (IGC). Expression of p21(WAF1/CIP1) was found in 47.6% of incomplete intestinal metaplasia (IM), 36.7% of dysplasia (Dys) and 29.5% of IGC. The overexpression of cyclin E was more frequently present in carcinomas than in Dys (P < 0.05); moreover, high-level expression (> 25% in extent) of cyclin E was observed only among IGC. Abnormal Bcl-2 expression was present in 81.0% of incomplete IM, 69.4% of Dys and 22.9% of IGC. Along with progression of the lesion, the expression of c-met increased; in contrast, mucin 5AC decreased gradually. CONCLUSIONS The specific expression pattern in incomplete IM was mucin 5AC+/Bcl-2+/p53-/cyclin E-, while mucin 5AC-/cyclin E+ was specific for IGC. p53 was useful for distinguishing LGD from HGD. High-level expression of cyclin E might be an indicator for malignant transformation of dysplasia.
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675
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Chen K, Zou Y. Iodine nutritional status of adults during a period of salt iodization. J Public Health (Oxf) 2005; 26:144-6. [PMID: 15284316 DOI: 10.1093/pubmed/fdh129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND To measure the iodine nutritional status of island adults in Zhoushan, China. METHODS A comparison study was carried out in eight villages. These were selected from iodized salt and non-iodized salt districts of Zhoushan island by random sampling. The Mann-Whitney test was used to compare the urinary iodine concentration and dietary iodine intake between the two districts. RESULTS The median of urinary iodine concentration in the non-iodized salt group was 90 micrograms/l, which was lower than 194 micrograms/l in the iodized salt group (u = 14.673; p < 0.000), whereas the median of daily dietary iodine intake in the two groups was 128 and 147 micrograms, respectively (u = 1.847; p = 0.065). There was no significant correlation between dietary iodine intake and urinary iodine concentration (p = 0.095). CONCLUSIONS Salt iodization is necessary. Special characteristics of the island diet should also be considered.
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