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Chen L, Xie B, Yu T. [Identification of volatile compounds of hawthorn by gas chromatography/mass spectrometry (GC/MS)]. Se Pu 1997; 15:219-21. [PMID: 15739361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
The volatile compounds of three cultivars of hawthorn were studied. Changko (Crataegus pinnatifida Bge.) hawthorn fruit was harvested after ripening from Hubei Province and those of Heihong and Dajinxing were from Shandong Province. The volatile compounds of each hawthorn cultivars were obtained by SDE (simultaneous distillation-extraction) equipment, by using CH2Cl2 as extracting solvent. The volatile extract was concentrated at 40-50 degrees C under vacuum to 0. 05mL or so and was ready for GC and GC/MS analysis. A DB-Wax fused silica capillary column (50m x 0.32mm i.d.; 1microm thickness) and a flame ionization detector (FID) was employed in GC analysis. The temperature program included of a 5 min isothermal period at 40 degrees C, temperature increases of 2 degrees C/min from 40 degrees C to 240 degrees C, and a 60 min isothermal period at 240 degrees C. Mass spectra were obtained by electron impact at 70eV and a source temperature of 250 degrees C. Thirty-two volatile compounds of the hawthorn fruit were identified, which comprised 61%-68% of the volatile fraction. The ten major components were cis-3-hexenol, cis-3-hexenyl acetate, alpha-terpineol, furfural, hexanol, hexyl acetate, nonanal, citral, 3-penten-2-one and trans-2-decenal. The molecular weight range of the major volatile fraction covers from C3 to C10. Both qualitative and quantitative differences in the volatile constituents among the three cultivars were not remarkable.
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Xie B, Heald SC, Camm AJ, Rowland E, Ward DE. Radiofrequency catheter ablation of accessory atrioventricular pathways: primary failure and recurrence of conduction. Heart 1997; 77:363-8. [PMID: 9155618 PMCID: PMC484733 DOI: 10.1136/hrt.77.4.363] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE To identify possible factors associated with primary failure of radiofrequency ablation of accessory pathways or recurrence of accessory pathway conduction. PATIENTS AND METHODS Radiofrequency ablation of accessory pathways failed in 25 of 243 patients, and recurrence of accessory pathway conduction occurred in an additional 13 patients. Factors possibly related to primary failure and recurrence were analysed. RESULTS Primary failure and recurrence were less frequent in patients with left sided pathways (7% v 19%; 4% v 24%; P = 0.04). The factors that might relate to primary failure included an unstable catheter position (seven patients), a possible epicardial pathway (six patients), or misdiagnosis of accessory pathway location (two patients). The major factors for recurrence included the stability of the local atrial electrogram < or = 0.5 together with the stability of the local ventricular electrogram < or = 0.8, and prolonged time to pathway conduction block > or = 12 seconds). Thirty one patients underwent repeat ablation which was successful in 28. CONCLUSIONS Primary failure and recurrence were more frequent in patients with right sided pathways. An unstable catheter position and a possible epicardial pathway location are the main contributing factors for primary failure, while unstable local electrograms and prolonged time to block are independent predictors for recurrence.
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Yoshikawa H, Xie B, Oyamada T, Hiraga A, Yoshikawa T. Detection of bovine leukemia viruses (BLV) in mammary tissues of BLV antibody-positive cows affected by subclinical mastitis. J Vet Med Sci 1997; 59:301-2. [PMID: 9152942 DOI: 10.1292/jvms.59.301] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The mammary tissues of 6 cows with bovine leukemia virus (BLV) antibody and subclinical mastitis were investigated histopathologically, and their organ cultures were ultrastructurally observed. Numerous BLV particles, 110 to 120 nm in diameter, were seen around lymphocytes, which had infiltrated into mammary alveoli and showed blastogenesis under culture. Particles budding from the cell membrane were also found.
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MESH Headings
- Animals
- Antibodies, Viral/analysis
- Antibodies, Viral/blood
- Cattle
- Enzootic Bovine Leukosis/complications
- Enzootic Bovine Leukosis/diagnosis
- Enzootic Bovine Leukosis/immunology
- Female
- Leukemia Virus, Bovine/immunology
- Leukemia Virus, Bovine/isolation & purification
- Leukemia Virus, Bovine/ultrastructure
- Lymphocytes/chemistry
- Lymphocytes/pathology
- Lymphocytes/virology
- Mammary Glands, Animal/chemistry
- Mammary Glands, Animal/pathology
- Mammary Glands, Animal/virology
- Mastitis, Bovine/etiology
- Mastitis, Bovine/pathology
- Mastitis, Bovine/virology
- Microscopy, Electron/veterinary
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Su WC, Kitagawa M, Xue N, Xie B, Garofalo S, Cho J, Deng C, Horton WA, Fu XY. Activation of Stat1 by mutant fibroblast growth-factor receptor in thanatophoric dysplasia type II dwarfism. Nature 1997; 386:288-92. [PMID: 9069288 DOI: 10.1038/386288a0] [Citation(s) in RCA: 255] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The achondroplasia class of chondrodysplasias comprises the most common genetic forms of dwarfism in humans and includes achondroplasia, hypochondroplasia and thanatophoric dysplasia types I and II (TDI and TDII), which are caused by different mutations in a fibroblast growth-factor receptor FGFR3 (ref. 1). The molecular mechanism and the mediators of these FGFR3-related growth abnormalities are not known. Here we show that mutant TDII FGFR3 has a constitutive tyrosine kinase activity which can specifically activate the transcription factor Stat1 (for signal transducer and activator of transcription). Furthermore, expression of TDII FGFR3 induced nuclear translocation of Stat1, expression of the cell-cycle inhibitor p21(WAF1/CIP1), and growth arrest of the cell. Thus, TDII FGFR3 may use Stat1 as a mediator of growth retardation in bone development. Consistent with this, Stat1 activation and increased p21(WAF1/CIP1) expression was found in the cartilage cells from the TDII fetus, but not in those from the normal fetus. Thus, abnormal STAT activation and p21(WAF1/CIP1) expression by the TDII mutant receptor may be responsible for this FGFR3-related bone disease.
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Xie B, Oyamada T, Yoshikawa H, Oyamada T, Yoshikawa T. Detection of proviral DNA of bovine leukaemia virus in cattle by a combination of in-situ hybridization and the polymerase chain reaction. J Comp Pathol 1997; 116:87-96. [PMID: 9076603 DOI: 10.1016/s0021-9975(97)80046-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Bovine leukaemia virus (BLV) proviral DNA was detected in lymphocytes isolated from cattle with persistent lymphocytosis (PL) by the polymerase chain reaction (PCR) and in-situ hybridization (ISH) with a biotinylated pX DNA probe. Many positive cells were observed when short-term culture and a combination of ISH with PCR were used. Immunohistochemical examination of lymphocytes isolated from the lymph node showed that BLV attached mainly to surface immunoglobulins (SIg) of positive B lymphocytes, and to a few tumour-associated antigen (TAA)-, PanT-, and CD8-positive cells and non-CD4 positive cells. Electron microscopical examination revealed colloidal gold particles within the nuclei and cytoplasm of lymphocytes. Lymphoid cells from neoplastic lymph node of enzootic bovine leukosis (EBL) cases gave particularly strong positive signals with the ISH-PCR method. The technique of combined ISH and PCR with a biotinylated pX probe may prove useful in future studies of EBL.
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181
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Danielsson B, Xie B. Thermistor-based biosensing. EXS 1997; 81:71-85. [PMID: 9002198 DOI: 10.1007/978-3-0348-9045-8_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In this review a universal thermistor-based biosensor system is described with examples from clinical chemistry, bioprocess monitoring and environmental control. The technique is based on the measurement of the small temperature changes associated with enzymatic reactions occurring in a microreactor with immobilized enzyme. The system has good operational stability and a sensitivity that permits measurements down to 1 microM concentrations. Current developments include devices constructed by micromachining for multisensing purposes and miniaturised instrumentation intended for use in portable monitoring. With use of special supports for enzyme immobilisation even untreated whole blood samples can be applied. Another current line of investigation involves hybrid biosensors, such as combinations of electrochemistry and calorimetry into bioelectrocalorimetric devices with interesting new properties.
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182
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Liu JJ, Doolan LA, Xie B, Chen JR, Buxton BF. Direct vasodilator effect of milrinone, an inotropic drug, on arterial coronary bypass grafts. FANZCA . J Thorac Cardiovasc Surg 1997; 113:108-13. [PMID: 9011679 DOI: 10.1016/s0022-5223(97)70405-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Milrinone is an inotropic drug with vasodilator activity that has been shown to be useful in increasing cardiac output and decreasing wedge pressure. Despite these advantages, it is unknown whether this drug can be used for the treatment of perioperative spasm of coronary bypass grafts. This study was undertaken to investigate the in vitro vascular effect of milrinone on internal thoracic arteries obtained from patients undergoing coronary artery bypass grafting. The results showed that milrinone produced a potent, concentration-dependent, preventive effect on the norepinephrine-induced contraction of internal thoracic arteries, as well as reversing contraction of internal thoracic arteries by receptor-dependent agents, including the thromboxane A2 mimetic U46619, the vasoconstrictor peptide endothelin-1, and the alpha1-adrenal receptor agonist phenylephrine. The relaxing effect of milrinone was weaker, however, on internal thoracic arteries contracted with 25 mmol/L potassium chloride. Comparison of milrinone with other vasodilators, including papaverine, nitroprusside, and glyceryl trinitrate, showed milrinone to be more potent than papaverine but less potent than nitroprusside and glyceryl trinitrate. The inhibitory effect of milrinone on internal thoracic artery contraction appeared as a reduction in contractile force, not as an increase in the values of concentrations of the agonists causing 50% maximal contraction, which indicates that milrinone exerts its vasodilator effect directly on the smooth muscles, not on the membrane receptors. The results also showed no significant difference in relaxing effect between internal thoracic artery rings with and without endothelium. In conclusion, this study provides experimental evidence that milrinone is a potent, endothelium-independent, direct vasodilator of the human internal thoracic artery and provides the scientific rationale for a future clinical trial with this drug for the perioperative treatment of internal thoracic artery spasm in cardiac surgical patients.
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183
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Shah CP, Thakur RK, Ip JH, Xie B, Guiraudon GM. Management of mobile right atrial thrombi: a therapeutic dilemma. J Card Surg 1996; 11:428-31. [PMID: 9083870 DOI: 10.1111/j.1540-8191.1996.tb00077.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Mobile right atrial thrombus is an uncommon finding on two-dimensional (2D) echocardiography. Therapeutic alternatives include systemic heparinization, systemic or local thrombolysis, and surgical removal. We report our clinical experience in six patients over a 3-year period (6000 echocardiograms) at a tertiary care referral center. METHODS There were four men and two women with a mean age of 63 years (range: 47 to 73 years). Indications for echocardiography consisted of progressive dyspnea and chest pain in five patients and syncope with chest pain in one patient. RESULTS All were observed to have a mobile thrombus in the right atrium. Ventilation perfusion (V/Q) scanning confirmed V/Q mismatch in all patients. Subsequent echocardiography (minutes to 1 day later) in three patients demonstrated absence of the thrombus suggesting pulmonary embolization. One patient died during transesophageal echocardiography (TEE) and autopsy confirmed a large pulmonary embolization in the main pulmonary artery. Treatment consisted of heparinization in 3 patients, systemic thrombolysis in 1 patient, and surgical removal of the thrombus in 1 patient. At surgery, a long serpiginous thrombus was seen in the right atrium, tethered to a fenestrated eustachian valve. There were 3 deaths: 1 patient treated with heparin; 1 patient treated with thrombolysis; and 1 during TEE. Two of the three patients treated with heparin and one patient undergoing surgical removal survived hospitalization. CONCLUSIONS Mobile thrombus in the right atrium is an unusual echocardiographic finding. It portends a poor prognosis with death due to pulmonary embolism.
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184
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Lin SX, Xie B, Li B, Zhou M. Chromatography of hydroxysteroid dehydrogenases. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1996; 684:99-105. [PMID: 8906468 DOI: 10.1016/0378-4347(96)00180-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The structure-function study of hydroxysteoid dehydrogenases has stimulated the development of their chromatography, which in turn reveals more mechanisms of these enzymes. Due to the various membrane associations and mild hydrophobic nature of most of the enzymes studied up to now, hydrophobic interaction chromatography has played a crucial role in their purification, using media such as phenyl-Superose or Sepharose-PEG. At the same time, affinity chromatography, especially the dye-containing columns, proves very efficient for these dehydrogenases, as the latter utilizes adenylyl-containing cofactors. Elution by their specific ligand facilitates their purification. In this paper, the use of detergents in the purification of these enzymes is also reviewed. Hydroxysteroid dehydrogenase preparation is further improved by rapid purification which facilitates the elimination of protein microheterogeneity, caused in vitro by oxidation, reduction or partial proteolysis. This process was shown to increase the crystallizability of the enzymes [Lin et al., J. Cryst. Growth, 122 (1992) 242-245; Zhu et al., J. Mol. Biol., 234 (1993) 242-244]. The fast purification permitted a simpler procedure and better combination of various columns than conventional chromatography. This leads to even higher efficiency, yielding homogeneous and highly active preparations.
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185
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Xie B, Heald SC, Camm AJ, Rowland E, Ward DE. Successful radiofrequency ablation of accessory pathways with the first energy delivery: the anatomic and electrical characteristics. Eur Heart J 1996; 17:1072-9. [PMID: 8809526 DOI: 10.1093/oxfordjournals.eurheartj.a015004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Successful ablation of accessory pathways has been achieved at the first energy delivery site in some patients, but factors permitting success at the first site are unclear. Accessory pathway location, surface and endocardial electrogram characteristics in each location were analysed and compared between the patients with first site block (group A, 34 patients) and those in whom multiple sites (median seven sites) were required (group B, 133 patients). No patients with right free-wall pathways had first site block. In group A surface electrocardiograms were more pre-excited (QRS duration: 132 +/- 20 vs 120 +/- 17 ms, P < 0.01). For left free-wall and septal pathways, the interval from the onset of the earliest delta wave on surface electrocardiogram to local ventricular activation (QRS-V) was more negative and the local atrioventricular interval (AV) was shorter in group A; the positive predictive value of a QRS-V < or = 0 ms, an AV < or = 30 ms and the presence of a possible accessory pathway potential was 67% for left free-wall and of a QRS-V < or = -10 ms with an AV < or = 30 ms was 100% for septal pathways. During retrograde mapping of concealed left free-wall and right anteroseptal pathways (first site block was not achieved in other locations) the positive predictive value of a local ventriculoatrial interval < or = 30 ms was 55%. Accessory pathway location correlated strongly with the chances of first site block, suggesting that anatomical features are important. Maximizing pre-excitation may be of benefit in achieving first site block. Delivery of energy to a site with special endocardial electrogram features was associated with an increased likelihood of first site block.
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186
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Xie B, Heald SC, Camm AJ, Rowland E, Ward DE. Characteristics of bipolar electrograms during anterograde mapping: the importance of accessory atrioventricular pathway location. Am Heart J 1996; 131:720-3. [PMID: 8721645 DOI: 10.1016/s0002-8703(96)90277-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Local endocardial electrograms recorded at successful radiofrequency ablation sites during anterograde mapping (QRS-V interval, atrioventricular [AV] interval, AV ratio, the presence of accessory pathway potential, and stability of atrial and ventricular electrogram) were analyzed and compared according to location of accessory pathways. The mitral and tricuspid annuli were divided into 10 regions. Endocardial electrograms differed with regard to location of accessory AV pathways. The QRS-V interval was more negative in right posteroseptal, right free wall and right anteroseptal locations than the interval in other locations. The AV interval was longer in posteroseptal than the interval in left and right free wall sites. The stability of atrial and ventricular electrograms was better in left free wall sites than in posteroseptal sites and worst in right free wall and right anteroseptal sites. The variation in local electrograms at successful ablation sites with respect to pathway location may partly explain the low predictive value and the marked variation in previously suggested criteria for selecting target sites for radiofrequency energy delivery. The results also imply that the influence of accessory pathway location must be considered when attempts are made to establish electrogram-based criteria for predicting successful ablation of accessory pathways.
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187
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Seo H, Xie B, Wang S, Yoshikawa H, Oyamada T, Yoshikawa T. Ultrastructure of hepatocytes in copper-deficient Sika deer (Cervus nippon Temminck). J Comp Pathol 1996; 114:283-90. [PMID: 8762586 DOI: 10.1016/s0021-9975(96)80050-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The livers of 13 Sika deer (Cervus nippon Temminck) aged 4 to 9 years and suffering from copper deficiency (enzootic ataxia) were examined histologically, histochemically and by electron microscopy. In addition, the serum and liver copper concentrations, measured in three animals, were found to be low. Histologically, the hepatocytes exhibited cloudy swelling, and numerous haemosiderin deposits were seen in the hepatocytes and Kupffer cells. Staining with p-dimethyl amino-benzylidene-rhodamine revealed distinctly fewer copper granules than normal. Histochemically, 3,3'-diaminobenzidine-H2O2 staining revealed increased numbers of catalase-positive granules around nuclei. Electron microscopically, "giant" and bizarre-shaped mitochondria, irregular depression of the mitochondrial membrane, and fusion of cristae were noted. Disorders of copper-containing enzymes, including cytochrome oxidase, caeruloplasmin and monoamine oxidase, may have been responsible for the mitochondrial abnormalities.
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188
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Ward DE, Xie B, Rowland E. Ablation of atrial flutter using the anatomical method: results and long-term follow-up. J Interv Cardiol 1995; 8:697-700. [PMID: 10159761 DOI: 10.1111/j.1540-8183.1995.tb00920.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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189
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Dinney CP, Fishbeck R, Singh RK, Eve B, Pathak S, Brown N, Xie B, Fan D, Bucana CD, Fidler IJ. Isolation and characterization of metastatic variants from human transitional cell carcinoma passaged by orthotopic implantation in athymic nude mice. J Urol 1995. [PMID: 7658585 DOI: 10.1016/s0022-5347(01)66923-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSE These studies were designed to develop an orthotopic model for human bladder cancer and to isolate variant metastatic cell lines. MATERIALS AND METHODS The human bladder cancer cell line 253J was implanted into the muscular wall of the bladder of athymic nude mice. By in vivo recycling, we selected for 2 variant cell lines: 253J B-V, a bladder line isolated after 5 serial passages in the bladder, and 253J lung-IV, established from a lung tumor nodule that was recycled through the bladder. RESULTS These 2 cell lines showed enhanced tumorigenicity, as measured by a decreased latent period, and rapid growth as compared with the parental cell line. Moreover, orthotopic implantation of these cell lines resulted in metastasis to the lungs. These in vivo-selected, metastatic cell lines exhibited unique karyotypic alterations, increased anchorage-independent growth, overexpression of basic fibroblast growth factor, altered expression of adhesion molecules and the ability to migrate through Matrigel. CONCLUSIONS This reproducible model of human bladder cancer offers the opportunity to study cellular properties associated with tumor progression and metastasis and is suitable for the evaluation of new therapeutic strategies for invasive bladder cancer.
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190
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Amine A, Digua K, Xie B, Danielsson B. A Microdialysis Probe Coupled with A Miniaturized Thermal Glucose Sensor for In Vivo Monitoring. ANAL LETT 1995. [DOI: 10.1080/00032719508000371] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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191
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Liu JJ, Xie B, Thurlow PJ, Wiley JS, Chen JR. Various cells release a stable small molecule that inhibits endothelium-dependent relaxation. THE AMERICAN JOURNAL OF PHYSIOLOGY 1995; 269:H1303-11. [PMID: 7485562 DOI: 10.1152/ajpheart.1995.269.4.h1303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Previous studies have shown that neutrophils release a stable factor that inhibits endothelium-dependent relaxation. In the present studies, the effects of supernatants derived from various cells on endothelium-dependent relaxation were studied. Cells were obtained from seven sources: human hematopoietic cells including mononuclear leukocytes (MONO), polymorphonuclear leukocytes (PMNs), and chronic lymphocytic leukemia (CLL) cells; cells of the cardiovascular system including human endothelial cell line ECV304, human smooth muscle cells, and rat myocardial cells; and the tumor cell line HPB. These isolated or cultured cells were incubated for 1 h in Krebs solution to release the factor. The results showed that the supernatants from 10(5) cells/ml of all cells except the tumor cell line HPB produced a potent inhibitory effect on endothelium-dependent relaxation of rat aortic rings in response to acetylcholine and Ca2+ ionophores A23187 and ionomycin but not on endothelium-independent relaxation to nitroprusside and glyceryl trinitrate. When the concentration increased to 10(6) cell/ml, the supernatants from the tumor cell line HPB also slightly but significantly inhibited endothelium-dependent relaxation. The potency order was PMNs = MONO = CLL cells > cardiac cells > smooth muscle cells > the endothelial cell line ECV304 > the tumor cell line HPB. It seems that the hematopoietic cells and the cardiac cells are more active in release of the factor. The effect of this factor was rapid in onset and hard to wash out. A cyclooxygenase inhibitor or a thromboxane A2-prostaglandin H2 receptor antagonist partially but significantly reduced the effect of the factor.(ABSTRACT TRUNCATED AT 250 WORDS)
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192
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Dinney CP, Fishbeck R, Singh RK, Eve B, Pathak S, Brown N, Xie B, Fan D, Bucana CD, Fidler IJ. Isolation and characterization of metastatic variants from human transitional cell carcinoma passaged by orthotopic implantation in athymic nude mice. J Urol 1995; 154:1532-8. [PMID: 7658585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
PURPOSE These studies were designed to develop an orthotopic model for human bladder cancer and to isolate variant metastatic cell lines. MATERIALS AND METHODS The human bladder cancer cell line 253J was implanted into the muscular wall of the bladder of athymic nude mice. By in vivo recycling, we selected for 2 variant cell lines: 253J B-V, a bladder line isolated after 5 serial passages in the bladder, and 253J lung-IV, established from a lung tumor nodule that was recycled through the bladder. RESULTS These 2 cell lines showed enhanced tumorigenicity, as measured by a decreased latent period, and rapid growth as compared with the parental cell line. Moreover, orthotopic implantation of these cell lines resulted in metastasis to the lungs. These in vivo-selected, metastatic cell lines exhibited unique karyotypic alterations, increased anchorage-independent growth, overexpression of basic fibroblast growth factor, altered expression of adhesion molecules and the ability to migrate through Matrigel. CONCLUSIONS This reproducible model of human bladder cancer offers the opportunity to study cellular properties associated with tumor progression and metastasis and is suitable for the evaluation of new therapeutic strategies for invasive bladder cancer.
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193
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Murgatroyd FD, Xie B, Copie X, Blankoff I, Camm AJ, Malik M. Identification of atrial fibrillation episodes in ambulatory electrocardiographic recordings: validation of a method for obtaining labeled R-R interval files. Pacing Clin Electrophysiol 1995; 18:1315-20. [PMID: 7659586 DOI: 10.1111/j.1540-8159.1995.tb06972.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Current systems for analyzing ambulatory electrocardiograms (ECGs) are unable to distinguish precisely between sinus rhythm and atrial fibrillation (AF) episodes, and are unable to produce RR interval listings that distinguish AF from sinus rhythm on a beat-to-beat basis. We describe a method for obtaining such a computerized listing ("Composite Rhythm" file) from ambulatory recordings containing episodes of AF. The file lists the rhythm of each beat, its real time, and the QRS complex morphology. A visual inspection is made of a full printout of the recording to identify the precise time of onset and termination of each episode of AF. These times are entered into a computer and identified with the corresponding beats on a conventional RR interval file generated by Holter analysis. The method was validated using 1-hour segments from 20 ambulatory ECGs containing 145 episodes of AF. These were visually identified by four independent observers with a mean sensitivity of 99.1%. The first beat of AF was identified concordantly in 96% of episodes, with a discrepancy of < or = 3 beats in the other episodes. The times of 200 selected QRS complexes were then entered into the computer by each observer; 91.1% of these complexes were identified exactly and 100% were identified to within one beat. The Composite Rhythm files have several potential applications for testing AF detection algorithms and studying the mode of onset of AF.
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194
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Xie B, Harborn U, Mecklenburg M, Danielsson B. Urea and lactate determined in 1-microL whole-blood samples with a miniaturized thermal biosensor. Clin Chem 1994; 40:2282-7. [PMID: 7988016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A miniaturized flow-injected thermal biosensor was developed for the determination of urea and L-lactate in undiluted blood in 1-microL samples. The sensor employed a small enzyme column constructed of stainless steel tubing and microbead thermistors. Urease and lactate oxidase/catalase were separately immobilized onto controlled-pore glass beads, which, in turn, were charged into the enzyme column. With a flow rate of 70 microL/min, linear analytical ranges from 0.2 to at least 50 mmol/L and 0.2 to 14 mmol/L were obtained for urea and lactate, respectively. The relative standard deviations (CVs) for measurements of analyte in buffer were 0.91% for urea and 1.84% for lactate. For urea in whole blood, the CV for 50 determinations was 4.1%. Contrived samples containing various concentrations of urea and L-lactate in whole blood were determined with this sensor and with a spectrophotometric method. Comparisons of the results gave correlation coefficients of 0.989 and 0.984 for 30 blood urea and 30 blood lactate assays in concentrations ranging from 4 to 20.9 mmol/L and from 1.7 to 12.7 mmol/L, respectively.
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195
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Xie B, Harborn U, Mecklenburg M, Danielsson B. Urea and lactate determined in 1-microL whole-blood samples with a miniaturized thermal biosensor. Clin Chem 1994. [DOI: 10.1093/clinchem/40.12.2282] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
A miniaturized flow-injected thermal biosensor was developed for the determination of urea and L-lactate in undiluted blood in 1-microL samples. The sensor employed a small enzyme column constructed of stainless steel tubing and microbead thermistors. Urease and lactate oxidase/catalase were separately immobilized onto controlled-pore glass beads, which, in turn, were charged into the enzyme column. With a flow rate of 70 microL/min, linear analytical ranges from 0.2 to at least 50 mmol/L and 0.2 to 14 mmol/L were obtained for urea and lactate, respectively. The relative standard deviations (CVs) for measurements of analyte in buffer were 0.91% for urea and 1.84% for lactate. For urea in whole blood, the CV for 50 determinations was 4.1%. Contrived samples containing various concentrations of urea and L-lactate in whole blood were determined with this sensor and with a spectrophotometric method. Comparisons of the results gave correlation coefficients of 0.989 and 0.984 for 30 blood urea and 30 blood lactate assays in concentrations ranging from 4 to 20.9 mmol/L and from 1.7 to 12.7 mmol/L, respectively.
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Xie B, Murgatroyd FD, Heald SC, Camm AJ, Rowland E, Ward DE. Late follow-up of catheter ablation of atrial flutter using low-energy direct current. Am J Cardiol 1994; 74:947-51. [PMID: 7977129 DOI: 10.1016/0002-9149(94)90594-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Xie B, Heald SC, Bashir Y, Camm AJ, Ward DE. Radiofrequency catheter ablation of septal accessory atrioventricular pathways. Heart 1994; 72:281-4. [PMID: 7946782 PMCID: PMC1025518 DOI: 10.1136/hrt.72.3.281] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVE Septal accessory atrioventricular pathways are recognised as being more difficult to ablate than pathways in other locations. This paper describes an experience of 48 consecutive patients with septal accessory pathways who had catheter ablation with radiofrequency current. PATIENTS AND METHODS There were 28 male and 20 female patients, mean (SD) age 35 (17). 43 patients had a single accessory pathway and 5 patients had multiple accessory pathways. Pre-excitation was present in 37 patients, and 11 patients had concealed accessory pathways. 21 patients had had a previous electrophysiological study. Catheter ablation was undertaken with radiofrequency current delivered by a standard unipolar technique or by delivery of current across the septum (the bipolar technique). RESULTS The median total procedure time was 167 (83) minutes including a 30-40 minute observation period after the abolition of conduction by the accessory pathway. The median total fluoroscopic time was 56 (30) minutes. 42 (88%) out of 48 patients had successful ablation of the pathway during the first session. In the six patients in whom the procedure failed, five had a midseptal pathway and one had a right anteroseptal pathway. A second attempt at ablation was made in two patients and succeeded in both. In total, 49 accessory pathways were successfully ablated in 44 (92%) out of 48 patients. The bipolar technique was used in 11 patients and succeeded in 10 patients. Standard unipolar current delivery had previously failed in seven of the 11 patients. Complications developed in two patients with a mid septal pathway (one with complete atrioventricular block and the other with a small pericardial effusion). CONCLUSION Radiofrequency catheter ablation of septal accessory pathways is efficacious and safe. The procedure time can be shortened and success rate can be increased after improvement of the technique--that is, consideration of a bipolar approach for energy delivery in difficult cases.
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Liu JJ, Chen JR, Bradley CJ, Xie B, Johnston CI, Buxton BF. Autologous neutrophil derived supernatants inhibit endothelium dependent relaxation in human coronary bypass graft. Cardiovasc Res 1994; 28:1353-9. [PMID: 7954645 DOI: 10.1093/cvr/28.9.1353] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVE Spasm of internal mammary artery is a problem during coronary artery bypass grafting. The mechanism is unknown. The aim of this study was to determine whether supernatants derived from neutrophils affected endothelium dependent relaxation of human internal mammary artery. METHODS The studies involved use of an organ chamber, measurement of cytosolic Ca2+, electron microscopy, and chemical characterisation. RESULTS Autologous neutrophils and internal mammary artery were obtained from patients undergoing the bypass grafting. Supernatants derived from the neutrophils were used to treat the patients' internal mammary artery rings. The results showed that the supernatants derived from 1 x 10(3)-5 x 10(6) cells.ml-1 neutrophils produced a potent concentration dependent inhibition of the endothelium dependent relaxation to ATP, acetylcholine, and the calcium ionophore A23187, but not the endothelium independent relaxation to sodium nitroprusside. In cultured human endothelial cells, the neutrophil derived supernatants induced an increase in cytosolic calcium ([Ca2+]i), caused calcium oscillations, and desensitised the ATP induced increase in [Ca2+]i. The increased [Ca2+]i resulted from a calcium influx. The supernatants also induced an increase in vesicle formation and possibly exocytosis in the internal mammary artery endothelium. Chemical characterisation showed that the effect of the supernatants was caused by a factor that is stable to heat, extreme pH and protease, is negatively charged and weakly hydrophobic, and has a molecular weight under 500 Dalton. CONCLUSIONS Autologous neutrophils release a stable non-protein small molecule that disturbs internal mammary artery endothelial function. Since it raises [Ca2+]i and causes possible exocytosis, it may have functions beyond its inhibition of vascular relaxation. This factor could be one of the contributors to internal mammary artery spasm and late atherosclerosis.
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Xie B, Heald SC, Bashir Y, Katritsis D, Murgatroyd FD, Camm AJ, Rowland E, Ward DE. Localization of accessory pathways from the 12-lead electrocardiogram using a new algorithm. Am J Cardiol 1994; 74:161-5. [PMID: 8023781 DOI: 10.1016/0002-9149(94)90090-6] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A new algorithm (St. George's algorithm), based on the polarity and morphology of QRS complexes rather than delta waves, was developed for localizing accessory pathways to 1 of 9 sites on the atrioventricular annuli. This was compared with algorithms previously proposed by Skeberis et al (localizing to 1 of 7 sites) and Milstein et al (localizing to 1 of 4 sites). The preexcited 12-lead electrocardiograms recorded during sinus rhythm in 106 consecutive patients (including 60 retrospectively analyzed patients and 46 prospectively analyzed patients) who underwent successful radiofrequency catheter ablation of a single accessory pathway were analyzed by 3 blinded observers using all 3 algorithms. The results were compared with the actual localization of accessory pathways as derived from endocardial mapping during catheter ablation. In all 106 patients, the accuracy of the 3 algorithms for 4 sites on the atrioventricular annuli (as considered by Milstein's method) was 72%, 79%, and 92% for Milstein's, Skeberis', and St. George's algorithms, respectively. For 7 sites (as considered by Skeberis' method), the accuracy was 65% (Skeberis' algorithm) and 88% (St. George's algorithm), and for 9 sites (as considered by our method) the accuracy was 86% (St. George's algorithm). In 46 prospectively analyzed patients, the accuracy of the 3 algorithms for 4 sites was 70% (Milstein's), 67% (Skeberis'), and 87% (St. George's); for 7 sites the accuracy was 61% (Skeberis') and 85% (St. George's), and for 9 sites the accuracy was 85% (St. George's). The reproducibility of St. George's and Skeberis' methods was better than that of Milstein's method.(ABSTRACT TRUNCATED AT 250 WORDS)
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Liu JJ, Xie B, Smith IL, Johnston CI, Buxton BF. A stable leukocyte-derived factor inhibits platelet aggregation. Biochem Biophys Res Commun 1994; 201:878-82. [PMID: 8003026 DOI: 10.1006/bbrc.1994.1783] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The effect of human polymorphonuclear leukocyte (PMN)-derived supernatants on platelet aggregation was studied. The results showed that the supernatants produced a concentration-dependent inhibition of the platelet aggregation in response to thrombin. The effect was mainly on the second phase of the aggregation, suggesting that the secretory mechanisms of the platelets are disturbed. The activity of the supernatants was not reduced after treatment with heat (95 degrees C for 30 minutes), extreme pH (pH 12 or pH 2) or protease. In conclusion, human PMNs release a stable non-protein factor that inhibits platelet aggregation.
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