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Lam MF, Lo WK, Tang C, Lui SL, Chan TM, Lai KN. Transport of Small Solutes in Peritonitis-free PD Patients. Int J Organ Transplant Med 2005. [DOI: 10.1016/s1561-5413(09)60198-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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277
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Lin J, Huang Y, Ding XX, Cheng C, Tang C, Qi SR. Metal oxide coating on carbon nanotubes by a methanol-thermal method. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2005; 5:932-6. [PMID: 16060156 DOI: 10.1166/jnn.2005.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A methanol-thermal method has been developed to fabricate one-dimensional composite nanowires by coating multiwalled carbon nanotubes with lanthanum oxide and iron oxide, respectively. The coating structure and composition have been investigated by transmission electron microscopy and the X-ray energy dispersive spectrum. Magnetic measurement for the iron oxide coatings indicated that the coercivity has been enhanced after coating. The method reported here provides a novel procedure for the fabrication of one-dimensional composite nanostructures.
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Lin AY, Fisher G, So S, Tang C, Levitt L. A phase II study of imatinib mesylate (IM) in patients (pts) with unresectable hepatocellular carcinoma (HCC). J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.4223] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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279
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Hu L, Li YX, Qu JP, Huang ZX, Huang XT, Ding XX, Tang C, Qi SR. MgO nanowire growth from Mg metal and SiO2. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2004; 4:1071-1075. [PMID: 15656205 DOI: 10.1166/jnn.2004.136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Comparative study on the diameter distribution of MgO nanowires has been carried out. MgO nanowires could be synthesized by the direct reaction between metallic magnesium and silica, and the obtained nanowires have diameters ranging from 50 to 200 nm and lengths of several hundreds nanometers, exhibiting a straight wire. The diameter can be downscaled to smaller than 50 nm, and the nanowire exhibits a curved and twisted one-dimensional structure with lengths up to several micrometers, when a fine support catalyst was used as the reactant. The diameter-controlled growth mechanism was also explained in this work.
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Kloster M, Tang C, Wingreen NS. Finding regulatory modules through large-scale gene-expression data analysis. ACTA ACUST UNITED AC 2004; 21:1172-9. [PMID: 15513996 DOI: 10.1093/bioinformatics/bti096] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
MOTIVATION The use of gene microchips has enabled a rapid accumulation of gene-expression data. One of the major challenges of analyzing this data is the diversity, in both size and signal strength, of the various modules in the gene regulatory networks of organisms. RESULTS Based on the iterative signature algorithm [Bergmann,S., Ihmels,J. and Barkai,N. (2002) Phys. Rev. E 67, 031902], we present an algorithm-the progressive iterative signature algorithm (PISA)-that, by sequentially eliminating modules, allows unsupervised identification of both large and small regulatory modules. We applied PISA to a large set of yeast gene-expression data, and, using the Gene Ontology database as a reference, found that the algorithm is much better able to identify regulatory modules than methods based on high-throughput transcription-factor binding experiments or on comparative genomics.
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Hu L, Li Y, Ding X, Tang C, Qi S. Insight into carbon nanotubes-template reaction at high temperature. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.08.131] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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282
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Zhang B, Wang S, Pang Y, Tang C, Du J. Alteration of heme-oxygenase-carbon monoxide pathway in calcified rat vascular smooth muscle cells. ACTA ACUST UNITED AC 2004; 93:109-15. [PMID: 14963676 DOI: 10.1007/s00392-004-0989-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2003] [Accepted: 06/24/2003] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The aim of the present study was to investigate the changes in heme-oxygenase (HO)-carbon monoxide (CO)-cyclic guanosine monophosphate (cGMP) pathway in clacified rat vascular smooth muscle cells (VSMCs). METHODS Calcification of cultured rat VSMCs was induced by incubation of VSMCs with beta-glycerophosphate. Cellular calcium content, ALP activities and (45)Ca uptake were measured. HO activity, HbCO formation and content of cGMP in VSMCs were determined. Immunocytochemistry for HO-1 expression was observed. RESULTS In comparison of control VSMCs, the cellular calcium content, ALP activity and (45)Ca uptake in calcified VSMCs were obviously increased. Immunocytochemistry showed that HO-1 expression was weak and not well distributed in calcified cells as compared to non-calcified VSMCs, but interestingly, there was stronger staining in calcified nodules than in VSMCs. Compared with VSMCs, HO-1 activity in calcified cells decreased by 42.7% [36.4 +/- 2.8 pmol (mg Pr x h)(-1) vs 63.5 x 5.3 pmol (mg Pr x h)(-1), p < 0.01], and HbCO formation decreased by 39.2% (3.38 x 0.69 micromol/mg Pr vs 5.56 +/- 0.48 micromol/mg Pr, p < 0.05). The cGMP content in calcified VSMCs was 78.1% lower than that of non-calcified VSMCs (4.3 +/- 0.51 vs 19.6 +/- 1.2 pmol/mg, p < 0.01). CONCLUSION The results showed that HO-CO-cGMP pathway in calcified vascular cells obviously changed, which might contribute to disturbance of vascular function.
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Chang L, Xu J, Yu F, Zhao J, Tang X, Tang C. Taurine protected myocardial mitochondria injury induced by hyperhomocysteinemia in rats. Amino Acids 2004; 27:37-48. [PMID: 15309570 DOI: 10.1007/s00726-004-0096-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2003] [Accepted: 02/18/2004] [Indexed: 11/26/2022]
Abstract
Taurine can protect against cardiovascular diseases, whereas elevated levels of plasma homocysteine are associated with atherosclerotic and thromboembolic cardiovascular diseases. To illustrate the effects of taurine on hyperhomocysteinemia, we observed the myocardial mitochondria dysfunction in the rats with hyperhomocysteinemia induced by diet methionine loading, and the therapeutic effect of taurine. A methionine diet increased plasma homocysteine concentration (133.51 +/- 27.91 micromol/L vs 12.31 +/- 2.58 micromol/L in control, P < 0.01), stimulated the production of reactive oxygen species (ROS) in the myocardial mitochondria, and inhibited the activities of mitochondrial Mn-superoxide dismutase and catalase. The 45Ca uptake and Ca2+-ATPase activity in the myocardial mitochondria were significantly lowered in rats with hyperhomocysteinemia. Taurine supplements effectively attenuated the hyperhomocysteinemia-induced ROS production and inhibition of Mn-superoxide dismutase and catalase activities in the myocardial mitochondria, and increased its 45Ca uptake and Ca2+-ATPase activity. Thus, taurine antagonizes the oxidative stress injury in the myocardial mitochondria induced by the hyperhomocysteinemia.
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Tang C, Chen V. The photocatalytic degradation of reactive black 5 using TiO2/UV in an annular photoreactor. WATER RESEARCH 2004; 38:2775-2781. [PMID: 15207608 DOI: 10.1016/j.watres.2004.03.020] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2003] [Revised: 02/10/2004] [Accepted: 03/12/2004] [Indexed: 05/24/2023]
Abstract
The textile effluent is a major industrial polluter because it is highly colored, containing about 15% unfixed dyes as well as high levels of salts that can potentially be discharged into the environment. Photocatalytic oxidation using an thin gap annular UV reactor with TiO2 was used to break down the colour of a synthetic effluent ranging up to 400 ppm in dye concentration of Reactive Black 5 and up to 80 g/L in NaCl. Results show that the reaction kinetics was dominated by the TiO2 loading, the initial dye concentration, and the dissolved oxygen concentration; with the other parameters showing less significant effects. High rates of decolorization were found, with a linear fit to the Langmuir-Hinshelwood equation yielding a reaction rate constant (k) of 2.45 ppm/min, and an adsorption equilibrium constant (K) of 0.048 ppm(-1) based on color removal. The presence of the combination of high dissolved oxygen (15 ppm) and sodium chloride (up to 80 g/L) was found to enhance the decolorization and mineralization rates of the reactive dye. However, pH was found to not significantly affect the degradation rate. Since textile effluent is strongly alkaline, this result is significant, as no solution neutralisation is required and direct treatment of the effluent is possible.
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Yin W, Liao D, Kusunoki M, Xi S, Tsutsumi K, Wang Z, Lian X, Koike T, Fan J, Yang Y, Tang C. NO-1886 decreases ectopic lipid deposition and protects pancreatic beta cells in diet-induced diabetic swine. J Endocrinol 2004; 180:399-408. [PMID: 15012594 DOI: 10.1677/joe.0.1800399] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The synthetic compound NO-1886 (ibrolipim) is a lipoprotein lipase activator that has been proven to be highly effective in lowering plasma triglycerides. Recently, we found that NO-1886 also reduced plasma free fatty acids and glucose in high-fat/high-sucrose diet-induced diabetic rabbits. In the current study, we investigated the effects of NO-1886 treatment on ectopic lipid deposition and the islet pathology in miniature swine fed a high-fat/high-sucrose diet. Our results showed that feeding this diet to miniature swine caused insulin resistance, increased lipid deposition in non-adipose tissue, such as in the heart, skeletal muscle, liver and pancreas, and also caused pancreatic beta cell damage. However, supplementing 1% NO-1886 (200 mg/kg per day) into the high-fat/high-sucrose diet decreased ectopic lipid deposition, improved insulin resistance, and alleviated the beta cell damage. These results suggest that improvement of lipid disorder, non-adipose tissue steatosis and insulin resistance may be very important for the protection of beta cell damage. Therefore, NO-1886 is potentially beneficial for the treatment of insulin-resistance syndrome.
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Beardsley DJS, Tang C, Chen BG, Lamborn C, Gomes E, Srimatkandada V. The disulfide-rich region of platelet glycoprotein (GP) IIIa contains hydrophilic peptide sequences that bind anti-GPIIIa autoantibodies from patients with immune thrombocytopenic purpura (ITP). Biophys Chem 2003; 105:503-15. [PMID: 14499914 DOI: 10.1016/s0301-4622(03)00111-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: 11/16/2022]
Abstract
Immune thrombocytopenic purpura (ITP) is an autoimmune blood disease caused by autoantibody-mediated destruction of blood platelets. Platelet glycoprotein (GP) IIb/IIIa is a common target for antiplatelet autoantibodies. The present studies were undertaken (1). to confirm whether the disulfide rich repeat region of GPIIIa contains target epitopes for antiplatelet antibodies in patients with ITP; (2). to determine whether these antigens were defined by peptide sequences in the absence of post-translational modification; and (3). to correlate observed immunologic reactivity with the recently solved X-ray crystallographic structure of an analogous integrin complex, the vitronectin receptor, alpha(V)beta(3). Recombinant fusion proteins of four GPIIIa extracellular sequences were prepared and purified. Immunoblotting results with purified recombinant peptides showed potent reactivity of 16 of 24 ITP patient serum anti-GPIIb/IIIa antibodies with the fusion protein containing the GPIIIa sequence of residues from 468 to 691. These results are consistent with a report by Kekomaki et al. that a 50 kDa chymotryptic digestion product of GPIIIa isolated from blood platelets contains target epitopes for serum antiplatelet antibodies in 16 of 33 ITP patients. Smaller peptides including residues 446-501 and residues 593-691 each reacted with only 5 of the 24 patient sera; furthermore all but 3 of these interactions were very weak. Visualization of the conformation of the extracellular portion of alpha(V)beta(3) reveals the location of the 222-residue antigenic GPIIIa (beta(3)) peptide 'B' at the immediately extracellular region of the protein that includes a beta-tail domain and several integrin-EGF domains. In summary, predictions of hydrophilicity, surface accessibility and antigenicity and the three dimensional structure of the beta(3) integrin correlate with autoantibody binding to a recombinant GPIIIa peptide 'B' containing residues 468-691.
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Longino J, Mullen B, Benghuzzi H, Tucci M, Tang C, Storey R, Puckett A. Evaluation of novel biodegradable cyclic carbonate polyester copolymers for cytocompatibility using MRC-5 cells. BIOMEDICAL SCIENCES INSTRUMENTATION 2003; 39:306-11. [PMID: 12724911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
The objective of this work was to synthesize and characterize a novel series of biodegradable cyclic carbonate polyester copolymers based on lactide and 5-methyl-5-benzyloxy-carbonyl-1,3-dioxan-2-one (MBC). Two compositions were selected for characterization. One copolymer was based on a racemic mixture of 1-lactide with 15.4 mole % MBC and the other was based on 1-lactide with 8.2 mole % MBC. These polymers contain carboxylic acid moieties along the backbone that may be used for tethering bioactive agents, forming ionic crosslinks or be reacted with vinyl containing monomers to allow free radical crosslinking. The initial materials evaluated have the carboxylic acid functionalities blocked with benzene. These polymers and the de-blocked versions may have potential applications for hard and soft tissue scaffolds, control drug delivery matrixes or a variety of other applications in medicine. The copolymer samples were pressed into 7.0-mm diameter disk using a KBr press. The disks were then sterilized using U.V radiation under a laminar flow hood. After sterilization, the copolymer disks were submerged in 2 ml of media and placed in a CO2 regulated incubator at 37 degrees C. A total of six groups per phase (n = 7 test tubes per group) were used in this study. Test tubes in groups I and III were plated with MRC-5 and subsequently treated with media alone (controls). Test tubes in groups II and IV were plated with MRC-5 and subsequently treated with media before being introduced to copolymer samples. Cell number, as well as, biochemical markers such as protein and malondialdehyde (MDA) were determined at the end of the 24, 48 and 72-hour time periods. Representative test tubes were subjected to an H&E staining procedure for microscopic morphological evaluation. The results of this evaluation suggest that the exposure of both copolymers produced a non-cytotoxic environment with the MRC-5 cell line. Although both copolymers are non-cytotoxic, the sample having the higher MBC content is the preferred composition based upon MDA levels and morphological evaluations.
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Hughes MA, Tang C, Cherry GW. Effect of intermittent radiant warming on proliferation of human dermal endothelial cells in vitro. J Wound Care 2003; 12:135-7. [PMID: 12715485 DOI: 10.12968/jowc.2003.12.4.26487] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE This study investigated the effect of Warm-Up therapy on the proliferation of human microvascular dermal endothelial cells. METHOD Endothelial cells from an adult subject were seeded in six-well plates and placed in an incubator at 32.5 degrees C. The following day Warm-Up dressings were placed over the plates, with or without warming cards. Cards set at 38 degrees C or 42 degrees C raised the temperature in the medium to maxima of 34.5 degrees C and 37.5 degrees C respectively. Units were switched on daily for three one-hour periods. Cell numbers were counted by haemocytometer. RESULTS Maximum stimulation of endothelial cell proliferation occurred under the 38 degrees C card, with cells numbering 135-158% of the controls (p < 0.05). the 42 degrees C card also stimulated cells (110-155%) but this did not reach statistical significance. CONCLUSION The accelerated proliferation of microvascular dermal endothelial cells achieved by intermittent radiant warming may have contributed to the increase in granulation tissue reported previously in our clinic.
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Tang C, Nuruzzaman M, Rengel Z. Screening wheat genotypes for tolerance of soil acidity. ACTA ACUST UNITED AC 2003. [DOI: 10.1071/ar02116] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A soil-based screening method was used to test tolerance of wheat genotypes to acidity. Plants were grown for 6 days in an acid soil with the pH adjusted to 3.9–5.8. The number and length of roots were measured. To validate the method, 12 wheat cultivars of known acidity tolerance and one acid-sensitive barley cultivar were grown on an acid soil in the field with or without amelioration of subsoil acidity. The relative yields of these wheat genotypes on the soil with subsoil acidity ranged from 50 to 89% of yields on soil without subsoil acidity, and were correlated with root growth parameters obtained in the glasshouse. The best correlation was obtained between relative yields in the field (y) and root length per plant (x) at pH 3.9 in the glasshouse (y = –43 + 52*log x, r = 0.95) or root length per plant at pH 3.9 as a percentage of root length at pH 4.8 (y = 1.2 + 46*log x, r = 0.94). Following validation of the glasshouse screening method in the field, 115 wheat genotypes, including cultivars and breeding lines, were screened in the glasshouse. A substantial genotypic variation in acidity tolerance was found, with root length per plant at pH 3.9 ranging from 66 to > 350 mm. Many Western Australian breeding lines displayed better tolerance than existing tolerant wheat cultivars. The screening system can be instrumental in breeding wheat for increased tolerance to acid soils.
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Zhang B, Tang C, Jiang Z, Qi Y, Pang Y, Du J. Effects of adrenomedullin on vascular calcification in rats. ACTA ACUST UNITED AC 2002; 91:568-74. [PMID: 12242953 DOI: 10.1007/s00392-002-0815-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The aim of the present study was to investigate the effect of adrenomedullin (ADM) on vascular calcification. METHODS The vascular calcification model was established in rats (VND group) by using vitamin D3 (300,000 IU/kg) and nicotine (25 mg/kg, two doses). The effect of liposome-encapsulated ADM was observed. Vascular calcium content, alkaline phosphatase (ALP) activity, ADM in aortic tissue and plasma, binding ability of 125I-ADM for ADM receptor on vascular plasma membrane and content of cAMP in vessels were measured. RESULTS Compared with control rats, the aortic calcium content and vascular ALP activity in rats of the VDN group was obviously increased; in addition ADM concentrations in plasma and vessels of rats in VDN group were increased. But the maximum binding sites of 125I-ADM for ADM receptor (Bmax) on vascular plasma membrane in rats of VDN group were significantly decreased compared with control rats. The affinity of 125I-ADM for the ADM receptor was reduced, as shown by the Kd value and vascular cAMP content being reduced in rats of the VDN group compared to the control group. The in vitro response of isolated vessels to ADM incubation was weakened. Administration of empty liposome had no effect on vascular calcification. But administration of ADM significantly decreased vascular calcium content and ALP activity. The Bmax of 125I-ADM for ADM receptors on vascular plasma membrane increased by 17.7% (p < 0.01), and the value of Kd decreased by 36.2% (P < 0.01) in rats treated with ADM as compared with rats of the VDN group. In addition, the vascular cAMP content and the response to ADM in isolated aorta were markedly increased. CONCLUSION Vascular calcification induced an alteration of the vascular ADM-ADM receptor-cAMP pathway. Treatment with exogenous ADM inhibited vascular calcification by improving the vascular ADM-ADM receptor-cAMP pathway.
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Liang JT, Huang KC, Lai HS, Lee PH, Cheng YM, Hsu HC, Cheng AL, Hsu CH, Yeh KH, Wang SM, Tang C, Chang KJ. High-frequency microsatellite instability predicts better chemosensitivity to high-dose 5-fluorouracil plus leucovorin chemotherapy for stage IV sporadic colorectal cancer after palliative bowel resection. Int J Cancer 2002; 101:519-25. [PMID: 12237891 DOI: 10.1002/ijc.10643] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The influence of MSI on treatment outcome of colorectal cancers remains unclear and deserves further investigation. We recruited 244 patients with stage IV sporadic colorectal cancers for our study, based on appropriate eligibility criteria. Patients were nonrandomly allocated to 2 treatment groups of either with or without high-dose 5-FU plus leucovorin chemotherapy (HDFL, 5-FU 2,600 mg/m(2) leucovorin 300 mg/m(2) maximum 500 mg). Each treatment group was further divided into 2 subgroups according to high-frequency MSI (MSI-H) status. MSI-H was defined as the appearance of MSI in at least 2 of the 5 examined chromosomal loci (BAT-25, BAT-26, D5S346, D2S123, D17S250). We compared clinicopathologic parameters, p53 overexpression and overall survival between the groups. In addition, 4 subgroups were identified as follows: MSI-H(+)HDFL(+), n = 35; MSI-H(-)HDFL(+), n = 134; MSI-H(+)HDFL(-), n = 17; MSI-H(-)HDFL(-), n = 58. There was no significant difference of background clinicopathologic data between the HDFL(+) and HDFL(-) treatment groups (p > 0.05). Survival analyses indicated that the patients of subgroup MSI-H(+)HDFL(+) survived significantly longer than those of subgroup MSI-H(-)HDFL(+), with median survival times of 24 (95% CI 20.2-27.9) and 13 (95% CI 11.6-14.4) months, respectively (p = 0.0001, log-rank test). In contrast, in patients without chemotherapy, the prognosis was poor irrespective of MSI status, with median survival times of 7.0 (95% CI 4.6-9.4) and 7.0 (95% CI 6.1-7.9) months in the MSI-H(+)HDFL(-) and MSI-H(-)HDFL(-) subgroups, respectively (p = 0.8205, log-rank test). MSI-H cancers responded significantly better to HDFL (p = 0.001), with a mean response rate of 65.71% (95% CI 49.98-81.44%) in subgroup MSI-H(+)HDFL(+) compared to 35.07% (95% CI 26.99-43.15%) in subgroup MSI-H(-)HDFL(+). There appeared to be no preferential metastatic site where response to HDFL can be predicted based on the MSI status of the primary tumor. Toxicity to HDFL was similarly minimal between MSI-H(+) and MSI-H(-) patients (p > 0.05). Multivariate analysis of all patients further indicated that MSI-H and chemotherapy were independent favorable prognostic parameters (p < 0.05). Thus, the better prognosis of stage IV sporadic colorectal cancers with MSI-H may be associated with better chemosensitivity, rather than lower aggressiveness in biologic behavior.
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Wang H, Tang C, Fan X, Yang G. [Research of high precision of temperature measurement in microwave hyperthermia therapy]. ZHONGGUO YI LIAO QI XIE ZA ZHI = CHINESE JOURNAL OF MEDICAL INSTRUMENTATION 2002; 26:332-4, 341. [PMID: 16104261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
This paper describes a new method of temperature measurement in microwave field. This method resolves a series of problems such as the microwave field suppression, the linearization of the temperature sensor and the sensor exchangeability.
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Cernik R, Bushnell-Wye G, Tang C, Dent A, Terril N, Diakun G, Barnes P, Greaves GN, Rayment T, Ryan A. A new facility for the study of materials processing on the SRS, Daresbury. Acta Crystallogr A 2002. [DOI: 10.1107/s0108767302087718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Feng G, Zhang FS, Li XL, Tian CY, Tang C, Rengel Z. Improved tolerance of maize plants to salt stress by arbuscular mycorrhiza is related to higher accumulation of soluble sugars in roots. MYCORRHIZA 2002; 12:185-90. [PMID: 12189473 DOI: 10.1007/s00572-002-0170-0] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2001] [Accepted: 02/21/2002] [Indexed: 05/19/2023]
Abstract
The effect of colonization with the arbuscular mycorrhizal (AM) fungus Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe on the growth and physiology of NaCl-stressed maize plants ( Zea mays L. cv. Yedan 13) was examined in the greenhouse. Maize plants were grown in sand with 0 or 100 mM NaCl and at two phosphorus (P) (0.05 and 0.1 mM) levels for 34 days, following 34 days of non-saline pre-treatment. Mycorrhizal plants maintained higher root and shoot dry weights. Concentrations of chlorophyll, P and soluble sugars were higher than in non-mycorrhizal plants under given NaCl and P levels. Sodium concentration in roots or shoots was similar in mycorrhizal and non-mycorrhizal plants. Mycorrhizal plants had higher electrolyte concentrations in roots and lower electrolyte leakage from roots than non-mycorrhizal plants under given NaCl and P levels. Although plants in the low P plus AM fungus treatment and those with high P minus AM fungus had similar P concentrations, the mycorrhizal plants still had higher dry weights, soluble sugars and electrolyte concentrations in roots. Similar relationships were observed regardless of the presence or absence of salt stress. Higher soluble sugars and electrolyte concentrations in mycorrhizal plants suggested a higher osmoregulating capacity of these plants. Alleviation of salt stress of a host plant by AM colonization appears not to be a specific effect. Furthermore, higher requirement for carbohydrates by AM fungi induces higher soluble sugar accumulation in host root tissues, which is independent of improvement in plant P status and enhances resistance to salt-induced osmotic stress in the mycorrhizal plant.
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Xu C, Tang C. [Discrimination of black inks by FT-Raman spectrometry]. FA YI XUE ZA ZHI 2002; 14:146-8, 191. [PMID: 11938888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Six brands of black inks on paper were examined by FT-Raman spectrometry. The results showed that the black inks could be discriminated by FT-Raman spectrometry. As the method is easy, quick and undestructive to samples, it is useful in black ink examination.
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Eisenmenger W, Du XX, Tang C, Zhao S, Wang Y, Rong F, Dai D, Guan M, Qi A. The first clinical results of "wide-focus and low-pressure" ESWL. ULTRASOUND IN MEDICINE & BIOLOGY 2002; 28:769-774. [PMID: 12113789 DOI: 10.1016/s0301-5629(02)00507-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A clinical study of the concept "wide-focus and low-pressure" extracorporal shock-wave lithotripsy (ESWL) was performed in a scientific cooperation between the Physical Institute of the University of Stuttgart and the Xixin Medical Instruments Co. Ltd. in Wuxian-Suzhou, China. In this cooperation, self-focusing electromagnetic shock-wave generator systems from the University of Stuttgart were integrated into Xixin lithotripters and installed in seven hospitals in China. A total of 297 detailed patient protocols revealed an average of 1532 shock pulses for successful treatment with no necessity for pain medication and auxiliary measures, and a stone-free rate of 86% after a follow-up of 3 months. These results are discussed in terms of the wide-focus low-pressure conditions and the mechanism of binary fragmentation by squeezing.
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Lin DP, Falkenberg C, Payne DA, Thakkar J, Tang C, Elly C. Kinetics of purging for the priority volatile organic compounds in water. Anal Chem 2002. [DOI: 10.1021/ac00056a009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Prueksaritanont T, Meng Y, Ma B, Leppert P, Hochman J, Tang C, Perkins J, Zrada M, Meissner R, Duggan ME, Lin JH. Differences in the absorption, metabolism and biliary excretion of a diastereomeric pair of alphavbeta3-antagonists in rat: limited role of P-glycoprotein. Xenobiotica 2002; 32:207-20. [PMID: 11958560 DOI: 10.1080/00498250110094403] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
1. The study investigated mechanisms underlying the pharmacokinetic differences of two zwitterionic diastereomers ((3S)-3-[(3R or 3S)-2-oxo-3-[3-(5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl)propyl]pyrrolidin-1-yl]-3-quinolin-3-ylpropanoic acid) with different lipophilicities using a combination of in vivo and in vitro approaches. 2. In rat, both isomers possessed comparable plasma clearances (CL). However, the more lipophilic diastereomer I exhibited a higher metabolic clearance (>2-fold higher than II), whereas the hydrophilic zwitterion II exhibited a higher biliary clearance (approximately 5-fold higher than I). Following oral administration, the bioavailability (F) of I (17%) was much higher than that of II (1%). 3. Consistent with these in vivo observations and the expectation based on their lipophilicity differences, the metabolism in rat liver microsomes was faster and the permeability in Caco-2 and LLC-PK1 cells and in situ rat intestinal loop was better for I than for II. 4. Only the absorption of the more lipophilic diastereomer I was subjected to an efflux system in the Caco-2 and in situ rat intestinal loop models. I was a good substrate for P-glycoprotein (P-gp) in both the human MDR1 and mouse mdr1a transfected cell lines, and in the wild-type mdr1a (-/-) mouse when compared with the P-gp-deficient mdr1a (-/-) mouse. Concomitant administration of I with verapamil in rat caused significant increases in oral AUC, F and Cmax of I without affecting its CL, further supporting the effect of P-gp in limiting the intestinal absorption of I in vivo in this animal model. 5. Since the findings that the lipophilic diastereomer I, but not II, was a good P-gp substrate were not in line with the observations that I was excreted to bile much slower than II and that I was absorbed better than II, the results suggested that P-gp played a minor role to the observed differences in the biliary excretion and intestinal absorption of the diastereomers I and II in rat.
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299
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Helling R, Li H, Mélin R, Miller J, Wingreen N, Zeng C, Tang C. The designability of protein structures. J Mol Graph Model 2002; 19:157-67. [PMID: 11381527 DOI: 10.1016/s1093-3263(00)00137-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
It has been noted that natural proteins adapt only a limited number of folds. Several researchers have investigated why and how nature has selected this small number of folds. Using simple models of protein folding, we demonstrate systematically that there is a "designability principle" behind nature's selection of protein folds. The designability of a structure (fold) is measured by the number of sequences that can design the structure--that is, sequences that possess the structure as their unique ground state. Structures differ drastically in terms of their designability. A small number of highly designable structures emerge with a number of associated sequences much larger than the average. These highly designable structures possess proteinlike secondary structures, motifs, and even tertiary symmetries. In addition, they are thermodynamically more stable and fold faster than other structures. These results suggest that protein structures are selected in nature because they are readily designed and stable against mutations, and that such a selection simultaneously leads to thermodynamic stability.
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Chen Y, Zhao M, Liu X, Yao W, Yang J, Zhang Z, Tang C. Urotensin II receptor in the rat airway smooth muscle and its effect on the rat airway smooth muscle cells proliferation. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 2001; 16:231-5. [PMID: 12903763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
OBJECTIVE To investigate the characteristics of urotensin II (U-II) receptor in the rat airway smooth muscle and the effect and signal transduction pathway of U-II on the proliferation of airway smooth muscle cells. METHODS Using 125I-UII binding assay to measure the Bmax and Kd of U-II receptor. Using the 3H-TdR incorporation to determine the effect of U-II on the proliferation of airway smooth muscle cells and its signal transduction pathway. Using Fura-2/AM to measure the effect of U-1I on the cytosolic free calcium concentration. RESULTS 1. 125I-UII binding increased with the time and reached saturation at 45 min. The B(max0 was (11.36 +/- 0.37)fmol/mg pr and Kd was (4.46 +/- 0.61) nmol/L. 2. U-II increased 3H-TdR incorporation of the airway smooth muscle cells in a dose-dependent manner. 3. H7, PD98059 and nicardipine, inhibitors of PKC, MAPK, calcium channel, respectively, significantly inhibited U-II-stimulated 3H-TdR incorporation of airway smooth muscle cells. W7, inhibitor of CaM-PK, had no effect. 4. Cyclosporin A, inhibitor of CaN, inhibited 3H-TdR incorporation of the airway smooth muscle cells induced by U-II in a dose-dependent manner. 5. U-II promoted cytosolic free calcium concentration increase by 18%. CONCLUSIONS 1. There was U-II receptor in the rat airway smooth muscle. 2. The effect of U-II-stimulated 3H-TdR incorporation of airway smooth muscle cells was mediated by such signal transduction pathway as Ca2+, PKC, MAPK and CaN, etc.
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