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Gu F, Chowdhary BP, Andersson L, Harbitz I, Gustavsson I. Assignment of the bovine immunoglobulin gamma heavy chain (IGHG) gene to chromosome 21q24 by in situ hybridization. Hereditas 2008; 117:237-40. [PMID: 1295852 DOI: 10.1111/j.1601-5223.1992.tb00020.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
By the use of in situ hybridization, the bovine immunoglobulin gamma heavy chain (IGHG) gene was assigned to chromosome 21q24. Fifteen percent of the total grains were scored on chromosome 21, with about 65 percent of these grains located on the q24 band. The present results confirm a previous synteny study and provide the precise chromosomal localization of this gene in the cattle genome.
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Gu F, Harbitz I, Chowdhary BP, Bosnes M, Gustavsson I. Chromosomal localization of the hormone sensitive lipase (LIPE) and insulin receptor (INSR) genes in pigs. Hereditas 2008; 117:231-6. [PMID: 1295851 DOI: 10.1111/j.1601-5223.1992.tb00019.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Using rat hormone sensitive lipase (LIPE) and human insulin receptor (INSR) cDNA probes, the LIPE gene was assigned to chromosome 6p11-q21 and the INSR gene to chromosome 2q11-q21 in pigs by in situ hybridization. In humans, these two genes are located on the q and p arms of chromosome 19, respectively. The present results provide the first in situ hybridization mapping data for porcine chromosome 2.
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Gu F, Harbitz I, Chowdhary BP, Chaudhary R, Gustavsson I. Localization of the 6-phosphogluconate dehydrogenase (PGD) gene in horses by in situ hybridization. Hereditas 2008; 117:93-5. [PMID: 1399707 DOI: 10.1111/j.1601-5223.1992.tb00012.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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Wang A, Bagalkot V, Gu F, Alexis F, Vasilliou C, Cima M, Jon S, Farokhzad O. Novel Targeted Aptamer-superparamagnetic Iron Oxide Nanoparticle Bioconjugates for Combined Prostate Cancer Imaging and Therapy. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.203] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Gu F, Chalaturnyk R. Numerical Simulation of Stress and Strain Due to Gas Sorption/Desorption and Their Effects on In Situ Permeability of Coalbeds. ACTA ACUST UNITED AC 2006. [DOI: 10.2118/06-10-05] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract
Most past studies on coal shrinkage/swelling due to gas adsorption/ desorption were based on experiments under no constraint conditions. In this paper, the changes of stress and strain measured on one coal specimen under uniaxial compression in a vacuum and under axial constraint conditions during CO2 adsorption are presented and numerically simulated. The simulation results show that a linear elastic deformation model, suitable to isotropic continuum media but widely assumed in analytical permeability models, cannot adequately simulate the deformation behaviour of coal mass even under uniaxial compression in a vacuum. The equivalent continuum medium (ECC) model considering the discontinuities of coal mass is successfully applied to simulate the deformation behaviour of the specimen for the uniaxial compression case and the axial constraint case before the occurrence of shear failure in the specimen.
A detailed review of the analytical permeability models is presented and their limitations in application are discussed in this paper. The permeability, in situ stress, and production simulated with two representative analytical permeability models are compared with those calculated using the discontinuum medium coupled (DMC) permeability model and the coupled simulation. The results indicate that the DMC model provides better estimates of permeability and production than the analytical permeability models because it considers the influence of many factors such as the discontinuities and anisotropies that are ignored in analytical permeability models.
Introduction
A comprehensive review made by Gu and Chalaturnyk(1) indicated that the permeability of a coalbed (i.e., the permeability of cleat (fracture) since matrix is almost impermeable) is the most important parameter for pressure depletion coalbed methane production (CBM) and enhanced coalbed methane recovery (ECBM). However, the permeability of a coalbed is not constant but varies drastically during production due to the changes of stress and/ or strain which result from the alternations of in situ conditions such as pressures, gas desorption or absorption, and temperature. In general, a decrease in pressure causes an increase of effective stresses, a cleat compression or closure, and a decrease of permeability. Concurrently, the decrease in pressure initiates gas desorption from coal resulting in shrinkage of the coal matrix, the widening or expansion of cleat apertures, and an increase of permeability. Field results have shown that the permeability of a coalbed decreases with an increase of minimum effective stresses (corresponding to increasing depth)(2). Mavor and Vaughn(3) illustrated that the permeability of three wells increased 2.7 to 7 times after producing for 3 to 4 years, according to field well tests. The results of work by van der Meer and Fokker(4) indicated that the permeability of a coalbed decreased from 3.65 mD to 0.985 mD due to the injection of CO2. Due to its significant influence on production, the dynamic change of permeability must be considered in the simulations predicting and evaluating CBM and ECBM processes.
There are two types of permeability models that can be used to consider the influence of permeability changes during production in simulations.
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Straume T, Anspaugh LR, Marchetti AA, Voigt G, Minenko V, Gu F, Men P, Trofimik S, Tretyakevich S, Drozdovitch V, Shagalova E, Zhukova O, Germenchuk M, Berlovich S. Measurement of 129 I and 137 Cs in soils from Belarus and reconstruction of 131I deposition from the Chernobyl accident. HEALTH PHYSICS 2006; 91:7-19. [PMID: 16775475 DOI: 10.1097/01.hp.0000184672.67781.a3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
I and Cs have been measured in a large number of soil samples collected throughout the country of Belarus to support efforts for thyroid-dose reconstruction following the Chernobyl accident. Samples of soil consisting of multiple 30-cm-deep cores per site were sampled following a selection process to ensure sites were undisturbed and representative. Samples were measured by accelerator mass spectrometry (AMS) for I, gamma spectrometry for Cs, and gas chromatography (GC) for total iodine. Results show that both I and Cs are retained firmly in the top approximately 15 to 20 cm of the soil. Our results also suggest that the correlation between I and Cs deposition across the country of Belarus is poor; hence, I is a better surrogate for I than is Cs. It was also noted that total iodine concentrations in topsoil from Belarus are low compared with other regions of the world where radiogenic thyroid cancer has been studied.
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Gu F, Chalaturnyk R. Sensitivity Study of Coalbed Methane Production With Reservoir and Geomechanic Coupling Simulation. ACTA ACUST UNITED AC 2005. [DOI: 10.2118/05-10-02] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract
Permeability of coal seams is one of the key factors for the success of coalbed methane (CBM) developments. It is dominated by cleat permeability in coal, which is very sensitive to the change of effective stresses. The coal matrix shrinkage due to methane production also influences cleat permeability. Using an explicit-coupling simulation method, which simultaneously simulates multiphase fluid flow and coal deformation, and a coupling permeability model, which considers the effects of the effective stress change and coal matrix shrinkage on cleat permeability, the sensitivity of CBM production to ten engineering, geologic, and coal intrinsic parameters such as cleat permeability, cleat spacing, well control area, depth, and methane content, etc., were studied in this paper. These parameters are stress and matrix shrinkage related parameters or have significantly influences on CBM production identified from previous studies. The production rate and final gas recovery from conventional simulations and coupling simulations are also compared. Of the parameters studied, permeability, cleat spacing, and in situ stresses were found to be the most sensitive parameters that influence CBM production. Medium sensitivity was found for the coefficient of matrix shrinkage, the Langmuir volume, pressure gradient, and well control area, while the least sensitive parameters included Poisson's ratio, Young's modulus, and the Langmuir pressure.
Introduction
With reserves of 84 ˜ 262 trillion m3 (2,980 ˜ 9,260 trillion ft3) all over the world(1), coalbed methane (CBM) has come to represent a real gas supply to meet current and future natural gas demands. In the United States, CBM accounted for 10% of dry gas reserves and 8% of dry gas production in 2003(2). The worldwide development of CBM is also accelerating in many other countries such as China, Canada, and Australia.
The success of CBM developments depends on many factors, but specific properties of a coal seam remain the fundamental controlling factor. Many people have investigated the effects of coal seam properties on CBM production and recovery(3–6). The studies of Sawyer et al. indicated that cleat (fracture) permeability and relative permeability, not gas diffusion, control long-term productivity, and that optimum well spacing also depends on cleat permeability(3). Reid et al.'s results showed that permeability, initial desorption pressure, and drainage area are the most important reservoir parameters for CBM production(4). Young et al. pointed out that permeability, well spacing, and the degree of coal saturation have the greatest impacts on the long-term performance of CBM wells(5). A completed parametric study by Roadifer et al. illustrated that for coal-only reservoirs (without adjacent sand layers), the five parameters having the most impact on the peak gas rate are, in order of highest to lowest, permeability, free gas saturation, degree of saturation of the coal, damage skin factor, and thickness(6).
The results of the above-mentioned studies clearly indicate that cleat permeability is likely the most important factor for CBM production. However, in all these investigations, permeability was considered as a constant.
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Hassanane MS, Gu F, Chowdhary BP, Andersson L, Gustavsson I. In situ hybridization mapping of the immunoglobulin gamma heavy chain (IGHG) gene to chromosome 20q23-q25 in river buffaloes. Hereditas 2004; 118:285-8. [PMID: 8376176 DOI: 10.1111/j.1601-5223.1993.t01-1-00285.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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60
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Hassanane MS, Chowdhary BP, Gu F, Andersson L, Gustavsson I. Mapping of the interferon gamma (IFNG) gene in river and swamp buffaloes by in situ hybridization. Hereditas 2004; 120:29-33. [PMID: 8206782 DOI: 10.1111/j.1601-5223.1994.00029.x] [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: 01/29/2023] Open
Abstract
In situ hybridization technique was applied using a tritiated (3H) bovine IFNG cDNA probe to regionally localize the gene on river and swamp buffalo chromosomes. The hybridization signals peaked on the 4q23-->q26 bands in river buffaloes and on the 1p24-->p26 bands in swamp buffaloes. The results are compared to the localization of the same gene in cattle. Possible evolutionary conservation in the Bovidae is discussed.
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61
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Lin M, Li B, Gu F, Yue Y, Huang Y, Chen Q, Zeng G, Xia J. [Study on psychoprophylaxis and monoamines neurotransmitter of patients with burning mouth syndrome]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 2001; 32:576-8. [PMID: 12528553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE Burning mouth syndrome (BMS) is a chronic ache disease, usually occurring in middle aged and old women. This study sought to understand the psychopathologic aspect and monoamines neurotransmitters in the plasma of the patients with BMS. METHODS Thirty cases were selected (26 females, 4 males); 30 normal control subjects were similar to the BMS cases on age and sex. All subjects were required to complete the Eysenck personality questionnaire (EPQ), and the Self-report Symptom Inventory, Symptom Check List-90 (SCL-90) questionnaire. In case a subject's L (lie) score exceeded 50, she (he) would be removed from the test. 2 ml of blood was drawn from the subject under restine conditions with a fast in the morning to examine norepinephrine and epinephrine contents by high efficient liquid chromatography. Chi-square test, analysis of variance and t'-test were performed. RESULTS The BMS group had higher scores of nervousness (N) and poikilergasia (P) and lower score of extro/introversion (E) as compared with the control (P < 0.05). The personality types in BMS group were focused on introversion and instability, but in the control group the types were focused on extroversion and stability (P < 0.05). The scores of 9 emotional factors of BMS group were significantly higher than those of the control group (P < 0.05), which indicated that the BMS patients had suffered from serial psychic disorders. The level of plasma norepinephrine in the BMS patients was higher than that of the control (P < 0.01). CONCLUSION The personality of BMS patients raised body response to harmful stimulations, and obvious psychic disorders in the patient may cause the functional disorders in central and sympathetic nervous systems, which may be associated with BMS' occurrence.
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Boudreaux B, MacMillan F, Teutloff C, Agalarov R, Gu F, Grimaldi S, Bittl R, Brettel K, Redding K. Mutations in both sides of the photosystem I reaction center identify the phylloquinone observed by electron paramagnetic resonance spectroscopy. J Biol Chem 2001; 276:37299-306. [PMID: 11489879 DOI: 10.1074/jbc.m102327200] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The core of photosystem I (PS1) is composed of the two related integral membrane polypeptides, PsaA and PsaB, which bind two symmetrical branches of cofactors, each consisting of two chlorophylls and a phylloquinone, that potentially link the primary electron donor and the tertiary acceptor. In an effort to identify amino acid residues near the phylloquinone binding sites, all tryptophans and histidines that are conserved between PsaA and PsaB in the region of the 10th and 11th transmembrane alpha-helices were mutated in Chlamydomonas reinhardtii. The mutant PS1 reaction centers appear to assemble normally and possess photochemical activity. An electron paramagnetic resonance (EPR) signal attributed to the phylloquinone anion radical (A(1)(-)) can be observed either transiently or after illumination of reaction centers with pre-reduced iron-sulfur clusters. Mutation of PsaA-Trp(693) to Phe resulted in an inability to photo-accumulate A(1)(-), whereas mutation of the analogous tryptophan in PsaB (PsaB-Trp(673)) did not produce this effect. The PsaA-W693F mutation also produced spectral changes in the time-resolved EPR spectrum of the P(700)(+) A(1)(-) radical pair, whereas the analogous mutation in PsaB had no observable effect. These observations indicate that the A(1)(-) phylloquinone radical observed by EPR occupies the phylloquinone-binding site containing PsaA-Trp(693). However, mutation of either tryptophan accelerated charge recombination from the terminal Fe-S clusters.
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63
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Gu F, Jin Z, Zhang D. [The etiology and clinical characteristics of central diabetes insipidus, a retrospective study of 408 cases]. ZHONGHUA YI XUE ZA ZHI 2001; 81:1166-71. [PMID: 11769702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To study the etiology and clinical characteristics of central diabetes insipidus (CDI). METHODS The clinical data of 408 cases with CDI treated in Peking Union Medical College Hospital between 1956 and 2000, including 113 cases caused by tumors in sella region, were analyzed retrospectively. Follow-up for three months to 16 years was made to 35 cases of CDI without etiological diagnosis during the first visit. RESULTS Most of the cases among children and youngsters fell ill at the age of 8-12 years, while most of the adult cases fell ill at the age of 25-35 years. Idiopathic CDI accounted for 52%. CDI caused by tumor in sella region accounted for about 33% among the child and youngster cases, among which germinoma made up about 65%. CDI caused by tumor in sella region accounted for about 22% in adult cases. Trauma-induced CDI accounted for 11% among adult cases, and about 5% among child and youngster cases. All the CDI cases caused by histiocytosis X, accounting for 3%, were children. A correct diagnosis was made within the period of two years' follow-up among 86% of the cases. For those with brain tumors, the long-term survival rate reached 80% with radiotherapy and/or operation performed without delay. CONCLUSION GH deficiency accompanied with growth failure is a potential indicator of CDI caused by space occupying lesion in sella region. A sudden alleviation of polydipsia may indicate the dysfunction of adrenal cortex. MRI is the most valuable examination means for tumor in sella region. Regular clinical follow-up with serial brain MRI may discover the covert tumor in sella region in cases diagnosed originally as idiopathic CDI. The cases without a correct diagnosis during the first visit should be followed-up every 3 to 6 months. The prognosis of the patients with CDI without tumor is satisfactory after ADH replacement. Radiotherapy is the most effective treatment of germinoma in sella region.
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64
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Meng X, Xu J, Gu F. Generalized dimension of the intersection between EEGs. BIOLOGICAL CYBERNETICS 2001; 85:313-318. [PMID: 11592628 DOI: 10.1007/s004220000231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The generalized dimension defined by [Mandelbrot (1995) J Fourier Anal Appl special J.P. Kahane issue: 409-432] was applied to studying the interrelationship between various parts of human cerebral cortex in different functional conditions. Taking EEG signals from different brain areas as different sets, the generalized dimensions of their intersections were calculated to describe the interrelationship between them. The results showed that the generalized dimensions of intersections in different brain states decreased according to the following order: rest with eyes open, closed, light sleep, and deep sleep. The generalized dimensions of intersections related to the left or right temporal lobe were higher than the others when the subjects was doing mental arithmetic, and there was a decrease when the subjects listened to soft classical music. In addition, it was found that there was a noticeable difference in singular spectra between epileptic patients and normal subjects, irrespective of whether the epileptic patient was experiencing a seizure or not.
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Abstract
The trans-Golgi network (TGN) is a major secretory pathway sorting station that directs newly synthesized proteins to different subcellular destinations. The TGN also receives extracellular materials and recycled molecules from endocytic compartments. In this review, we summarize recent progress on understanding TGN structure and the dynamics of trafficking to and from this compartment. Protein sorting into different transport vesicles requires specific interactions between sorting motifs on the cargo molecules and vesicle coat components that recognize these motifs. Current understanding of the various targeting signals and vesicle coat components that are involved in TGN sorting are discussed, as well as the molecules that participate in retrieval to this compartment in both yeast and mammalian cells. Besides proteins, lipids and lipid-modifying enzymes also participate actively in the formation of secretory vesicles. The possible mechanisms of action of these lipid hydrolases and lipid kinases are discussed. Finally, we summarize the fundamentally different apical and basolateral cell surface delivery mechanisms and the current facts and hypotheses on protein sorting from the TGN into the regulated secretory pathway in neuroendocrine cells.
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66
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Pikul S, Dunham KM, Almstead NG, De B, Natchus MG, Taiwo YO, Williams LE, Hynd BA, Hsieh LC, Janusz MJ, Gu F, Mieling GE. Heterocycle-based MMP inhibitors with P2' substituents. Bioorg Med Chem Lett 2001; 11:1009-13. [PMID: 11327577 DOI: 10.1016/s0960-894x(01)00137-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Potent and selective inhibition of matrix metalloproteinases was demonstrated for a series of sulfonamide-based hydroxamic acids. The design of the heterocyclic sulfonamides incorporates a six- or seven-member central ring with a P2' substituent that can be modified. Binding interactions of this substituent at the S2' site are believed to contribute to high inhibitory potency against stromelysin, collagenase-3 and gelatinases A and B, and to provide selectivity against collagenase-1 and matrilysin. An X-ray structure of a stromelysin inhibitor complex was obtained to provide insights into the SAR and selectivity trends observed for the series.
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Natchus MG, Bookland RG, Laufersweiler MJ, Pikul S, Almstead NG, De B, Janusz MJ, Hsieh LC, Gu F, Pokross ME, Patel VS, Garver SM, Peng SX, Branch TM, King SL, Baker TR, Foltz DJ, Mieling GE. Development of new carboxylic acid-based MMP inhibitors derived from functionalized propargylglycines. J Med Chem 2001; 44:1060-71. [PMID: 11297453 DOI: 10.1021/jm000477l] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of carboxylic acids were prepared from a propargylglycine scaffold and tested for efficacy as matrix metalloproteinase (MMP) inhibitors. Detailed SAR for the series is reported for four enzymes within the MMP family. The inhibitors were typically potent against collagenase-3 (MMP-13) and gelatinase A (MMP-2), while they spared collagenase-1 (MMP-1) and only moderately inhibited stromelysin (MMP-3). Compound 40 represents a typical inhibition profile of a compound with reasonable potency. Introduction of polar groups was required in order to generate inhibitors with acceptable water solubility, and this often resulted in a loss of potency as in compound 63. High serum protein binding proved to be a difficult hurdle with many compounds such as 48 showing >99% binding. Some compounds such as 64 displayed approximately 90% binding, but no reliable method was discovered for designing molecules with low protein binding. Finally, selected data regarding the pharmacokinetic behavior of these compounds is presented.
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68
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Natchus MG, Bookland RG, De B, Almstead NG, Pikul S, Janusz MJ, Heitmeyer SA, Hookfin EB, Hsieh LC, Dowty ME, Dietsch CR, Patel VS, Garver SM, Gu F, Pokross ME, Mieling GE, Baker TR, Foltz DJ, Peng SX, Bornes DM, Strojnowski MJ, Taiwo YO. Development of new hydroxamate matrix metalloproteinase inhibitors derived from functionalized 4-aminoprolines. J Med Chem 2000; 43:4948-63. [PMID: 11150165 DOI: 10.1021/jm000246e] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of hydroxamates was prepared from an aminoproline scaffold and tested for efficacy as matrix metalloproteinase (MMP) inhibitors. Detailed SAR for the series is reported for five enzymes within the MMP family, and a number of inhibitors, such as compound 47, display broad-spectrum activity with sub-nanomolar potency for some enzymes. Modifications of the P1' portion of the molecule played a key role in affecting both potency and selectivity within the MMP family. Longer-chain aliphatic substituents in this region of the molecule tended to increase potency for MMP-3 and decrease potency for MMP-1, as exemplified by compounds 48-50, while aromatic substituents, as in compound 52, generated broad-spectrum inhibition. The data is rationalized based upon X-ray crystal data which is also presented. While the in vitro peroral absorption seemed to be less predictable, it tended to decrease with longer and more hydrophilic substituents. Finally, a rat model of osteoarthritis was used to evaluate the efficacy of these compounds, and a direct link was established between their pharmacokinetics and their in vivo efficacy.
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69
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Zang Z, Xu H, Yu L, Yang D, Xie S, Shi Y, Li Z, Li J, Wang J, Li M, Guo Y, Gu F. Intravesical immunotoxin as adjuvant therapy to prevent the recurrence of bladder cancer. Chin Med J (Engl) 2000; 113:1002-6. [PMID: 11776112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To assess the intravesical application of immunotoxin as adjuvant therapy to prevent recurrence after tumor resection in bladder cancer patients. METHODS An anti-human immunotoxin against bladder carcinoma, BDI-1-RT, was prepared and its in vitro targeting cytotoxicity estimated. The immunoreactivity of BDI-1-RT with human bladder cancer tissue of different grades and stages was detected by immunohistochemical analysis. After safety test, intravesical administration of BDI-1-RT was performed in 31 patients while mitomycin C (MMC) was used in 36 patients serving as a control group. The recurrence rates and side effects in both groups were recorded. In addition, the development of human anti-mouse antibodies (HAMA) was determined by ELISA, to assess the potential safety of this immunotoxin. RESULTS In our study, BDI-1-RT had immunoreactivity with 81.6% of bladder transitional cell carcinomas. The immunoreactivity of BDI-1-RT correlated with tumor grade. High-grade carcinoma had stronger staining than low-grade (P < 0.05). There was no significant difference between the BDI-1-RT group (10%) and MMC group (19.3%) in recurrence rate (P > 0.05). Side effects, including systemic and local, were more frequent in the MMC group (11 of 36 patients versus 2 of 31, P < 0.05). HAMA was not detected in any of 7 patients. CONCLUSION Immunotoxin may have considerable potential in the prophylaxis of bladder transition cell carcinoma.
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Chen F, Xu J, Gu F, Yu X, Meng X, Qiu Z. Dynamic process of information transmission complexity in human brains. BIOLOGICAL CYBERNETICS 2000; 83:355-366. [PMID: 11039700 DOI: 10.1007/s004220000158] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Based on a complexity analysis of mutual information transmission of EEG developed by us [Xu J, Liu Z, Liu R, Yang Q (1997) Physica D 106: 363-374], dynamic processes of the complexity of mutual information transmission in human brains were studied. To diminish possible problems due to coarse graining preprocessing, some new measures of complexity were used. The results show that, just before and after generalized seizures, the complexities of almost all information transmission between different brain areas drop significantly; there is also a temporary decrease of complexity when subjects shift their attention. The above facts suggest that there is a transient decrease of information transmission complexity when brain state changes occur suddenly. Mental arithmetic tasks activate the left temporal lobe to exchange more information with other brain areas. The results hint that the methods used here might be an approach to observe quick processes in the living brain.
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71
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Gu F, Xi Z, Goldberg IH. DNA damage by thiol-activated neocarzinostatin chromophore at bulged sites. Biochemistry 2000; 39:4881-91. [PMID: 10769146 DOI: 10.1021/bi000007t] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bulge structures in nucleic acids are of general biological significance and are potential targets for therapeutic drugs. It has been shown in a previous study that thiol-activated neocarzinostatin chromophore is able to cleave duplex DNA selectively at a position opposite a single unpaired cytosine or thymine base on the 3' side. In this work, we studied in greater detail the nature of this type of cleavage and the basis for the selectivity of the bulge site cleavage over the usual strand cleavage at a T site in the duplex region by using duplexes containing an internal control and a bulge, which is composed of different types and number of bases. Experimental results indicated that the bulge-induced cleavage is initiated by 5' hydrogen abstraction and is greatly affected by the base composition of the bulge. A single-base bulge, especially when containing a purine, yields higher efficiency and greater selectivity for the bulge-induced cleavage. In particular, a single adenine base gives rise to the highest cleavage yield and provides over 20 times greater selectivity for cleavage at the bulge site compared with the internal control site in duplexes. The binding dissociation constants of postactivated drug for a stem-loop structure containing a one- or two-base bulge in the stem, measured by fluorescence quenching, show that the binding is about 3-4 times stronger for bulge-containing duplexes than for perfect hairpin duplexes. For RNA.DNA hybrid duplexes, where the DNA is the target strand and the RNA is the bulge-containing strand, bulge-induced cleavage was observed, although at low yield. On the other hand, when RNA is the nonbulge strand, no bulge-induced cleavage was found. When the reaction is performed in the absence of oxygen, the major product is a covalent adduct, and it is at the same location as the cleavage site under aerobic conditions.
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72
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Gu F. Epidemiological survey of benign prostatic hyperplasia and prostatic cancer in China. Chin Med J (Engl) 2000; 113:299-302. [PMID: 11775222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To evaluate the prevalence of benign prostatic hyperplasia (BPH) and prostatic cancer (CaP) in the mainland of China. METHODS The incidence of BPH and CaP in urological hospital was investigated in 1997 in 26 provinces and 4 metropolises scattered over the mainland of China. The change of hospital incidences of BPH and CaP in the Institute of Urology, Beijing Medical University from 1951 to 1997 was also reviewed. RESULTS The incidence of BPH and CaP in 1997 in 187 hospitals scattered over the mainland of China was 16.1% (15,459/95,749) and 1.5% (1389/95,749), respectively. The incidence of BPH and CaP in the Institute of Urology, Beijing University from 1951 to 1960 was 7.6% and 0.6%, respectively, while it was 18.5% and 3.4% from 1991 to 1997. CONCLUSION The hospital incidence of BPH and CaP is rising rapidly in China, but CaP is still not a common disease in China.
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Gu F, Gruenberg J. ARF1 regulates pH-dependent COP functions in the early endocytic pathway. J Biol Chem 2000; 275:8154-60. [PMID: 10713138 DOI: 10.1074/jbc.275.11.8154] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Coat proteins of the COP family were recently shown by us and others to be involved in membrane transport in the endocytic pathway, in addition to their known functions in the biosynthetic pathway. We have also shown that membrane association of endosomal COPs depends on the acidic endosomal pH, in contrast to biosynthetic COPs. In this paper, we report that both membrane recruitment of endosomal COPs and in vitro biogenesis of transport intermediates destined for late endosomes, depend on a cytosolic factor, which we identified as the small GTP-binding protein ARF1. Our data indicate that ARF1 does not act via activation of an endosomal phospholipase D. We also find that ARF1 membrane association is regulated by the endosomal pH, and that this controls the pH-dependent association of endosomal COPs. These studies thus show that ARF1 regulates COP functions in the endocytic pathway, and indicate that ARF1 acts as the cytosolic component of a transmembrane pH-sensing mechanism.
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Cheng M, De B, Pikul S, Almstead NG, Natchus MG, Anastasio MV, McPhail SJ, Snider CE, Taiwo YO, Chen L, Dunaway CM, Gu F, Dowty ME, Mieling GE, Janusz MJ, Wang-Weigand S. Design and synthesis of piperazine-based matrix metalloproteinase inhibitors. J Med Chem 2000; 43:369-80. [PMID: 10669564 DOI: 10.1021/jm990366q] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A new generation of cyclic matrix metalloproteinase (MMP) inhibitors derived from dl-piperazinecarboxylic acid has been described. The design involves: incorporation of hydroxamic acid as the bidentate chelating agent for catalytic Zn(2+), placement of a sulfonamide group at the 1N-position of the piperazine ring to fill the S1' pocket of the enzyme, and finally attachment of diverse functional groups at the 4N-position to optimize potency and peroral absorption. A unique combination of all three elements produced inhibitor 20 with high affinity for MMPs 1, 3, 9, and 13 (24, 18, 1.9, and 1.3 nM, respectively). X-ray crystallography data obtained for MMP-3 cocrystallized with 20 gave detailed information on key binding interactions defining an overall scaffold geometry for piperazine-based MMP inhibitors.
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Cheng M, De B, Almstead NG, Pikul S, Dowty ME, Dietsch CR, Dunaway CM, Gu F, Hsieh LC, Janusz MJ, Taiwo YO, Natchus MG, Hudlicky T, Mandel M. Design, synthesis, and biological evaluation of matrix metalloproteinase inhibitors derived from a modified proline scaffold. J Med Chem 1999; 42:5426-36. [PMID: 10639284 DOI: 10.1021/jm9904699] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The synthesis and structure-activity relationship (SAR) studies of a series of proline-based matrix metalloproteinase inhibitors are described. The data reveal a remarkable potency enhancement in those compounds that contain an sp(2) center at the C-4 carbon of the ring relative to similar, saturated compounds. This effect was noted in compounds that contained a functionalized oxime moiety or an exomethylene at C-4, and the potencies were typically <10 nM for MMP-3 and <100 nM for MMP-1. Comparisons were then made against compounds with similar functionality where the C-4 carbon was reduced to sp(3) hybridization and the effect was typically an order of magnitude loss in potency. A comparison of compounds 14 and 34 exemplifies this observation. An X-ray structure was obtained for a stromelysin-inhibitor complex which provided insights into the SAR and selectivity trends observed within the series. In vitro intestinal permeability data for many compounds was also accumulated.
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