1301
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Fontanesi J, Meyer D, Xu S, Tai D. Treatment of choroidal melanoma with I-125 plaque. Int J Radiat Oncol Biol Phys 1993; 26:619-23. [PMID: 8330991 DOI: 10.1016/0360-3016(93)90278-4] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSES To evaluate efficacy of I-125 episcleral plaque therapy in patients with ocular melanoma and determine survival, eventual visual acuity, and complications. METHODS AND MATERIALS Between July 1, 1984 and January 1, 1991, 144 patients with diagnosis of ocular melanoma were treated with high activity I-125 episcleral plaques. Tumor volumes ranged from 14 to 3449 mm3. Lesion size included small (n = 15; height < 5 mm, and/or largest basal diameter of 8-16 mm) and large (n = 45; height > 8 mm, and/or largest basal diameter > 16 mm). Apical doses ranged from 74.25 to 83.66 Gy with scleral doses ranging from 41 and 160 Gy. Follow-up has ranged from 25 to 90 months (Med = 46 months). RESULTS Ocular survival was noted in 130/144. Reasons for enucleation included progressive tumor growth (n = 4), extrascleral extension (n = 4), or blind/painful eye (n = 6), 94 patients developed complications which included cataract (n = 43), optic neuropathy (n = 12), neovascular glaucoma (n = 8) and retinopathies (n = 31). Visual acuity testing pre-episcleral plaque therapy revealed 102 patients with 20/200 vision; at last follow-up 59 patients demonstrated visual acuity testing of 20/200 or better. CONCLUSION The use of episcleral I-125 plaque therapy allows for safe and effective therapy in patients with ocular melanoma of various size depending on location and probable visual acuity outcome. A total apical dose of 75 Gy given at 60-65 cGy/hour provides durable local control with acceptable complication rates.
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1302
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Beales PE, Williams AJ, Signore A, Procaccini E, Xu S, Pozzilli P. The effect of a heparin analogue, ITF-5005, on diabetes incidence and insulitis in the non-obese diabetic mouse. Diabetes Res Clin Pract 1993; 21:5-9. [PMID: 8253022 DOI: 10.1016/0168-8227(93)90090-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
It has been suggested that heparin and its analogues may have a suppressive effect on the immune response by interfering with T-lymphocyte heparinase activity, thus altering the ability of T-lymphocytes to penetrate the extracellular matrix and migrate to target tissues. We have investigated whether a heparin analogue (ITF-5005) can alter lymphocytic infiltration of the endocrine pancreas (insulitis) and/or diabetes incidence in the non-obese diabetic (NOD) mouse. Sixty-four NOD mice were divided at weaning and injected subcutaneously five times per week with either 18, 36 or 72 micrograms/kg body weight of ITF-5005 or saline as a control. At 12 weeks of age, the animals were culled and their pancreata sectioned, stained and assessed 'blind' for insulitis and insulin containing cells. Insulitis was similar in all groups as was the proportion of insulin-containing cells. To determine the effect on diabetes incidence, two groups of mice were injected with either saline or 140 micrograms/kg body weight of ITF-5005 from weaning until 30 weeks of age. No difference was found in overall diabetes incidence; however, disease onset was significantly accelerated in the treated group. We conclude that ITF-5005, at the doses employed, has no effect on insulitis or the proportion of treated group. We conclude that ITF-5005, at the doses employed, has no effect on insulitis or the proportion of insulin-containing cells found in the pancreas, but that it can accelerate the course of diabetes in the NOD mouse.
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Abstract
The dissociation constants of piperidine (PD), 1-piperidineethanol (1–PE), N-methylmorpholine (MML), 4-(2-hydroxyethyl)morpholine (4-EML), and tropine (TP) have been determined at 15.0, 25.0, 35.0, 45.0, and 60.0 °C. The standard state enthalpy changes of the dissociation reaction for these amines have been obtained from the dependence of the dissociation constants upon temperature.
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1304
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Xu S. INDUPDAT: A SAS/IML Program for Selection Index Updating. J Hered 1993. [DOI: 10.1093/oxfordjournals.jhered.a111347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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1305
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Williams AJ, Beales PE, Krug J, Procaccini E, Signore A, Xu S, Gale EA, Pozzilli P. Tolbutamide reduces the incidence of diabetes mellitus, but not insulitis, in the non-obese-diabetic mouse. Diabetologia 1993; 36:487-92. [PMID: 8335169 DOI: 10.1007/bf02743262] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The functional state of beta cells may influence the rate of their destruction in Type 1 (insulin-dependent) diabetes mellitus. We examined the effect of diazoxide, which inhibits insulin secretion, or tolbutamide, which stimulates insulin secretion, upon the incidence of diabetes in the non-obese-diabetic (NOD) mouse. Female mice were treated from 3-30 weeks of age with diet containing diazoxide 250 mg.kg-1 or tolbutamide 125 mg.kg-1. The cumulative incidence of diabetes at 35 weeks was similar in the diazoxide (16 of 24) and control (18 of 24) groups, but reduced in the tolbutamide group (10 of 23, p < 0.04 vs control group). In a second experiment, treatment was started from 9 weeks of age, by which time insulitis is already present. The cumulative incidence of diabetes at 35 weeks was 16 of 24 in controls, 15 of 24 on diazoxide and 11 of 24 on tolbutamide (p = NS vs control). A third experiment compared the effect of treatment from 3 weeks with control diet or diet containing tolbutamide 125 mg.kg-1 or 500 mg.kg-1. Diabetes was reduced by tolbutamide treatment, with a cumulative incidence of 25 of 31 in controls, 18 of 30 on tolbutamide 125 mg.kg-1 (p < 0.04) and 14 of 32 on 500 mg.kg-1 (p < 0.002), although the difference between the two treatment groups failed to reach statistical significance. A fourth experiment showed that treatment from 3-12 weeks with diazoxide 1000 mg.kg-1 increased the extent of insulitis compared with controls and animals treated with tolbutamide 500 mg.kg-1.(ABSTRACT TRUNCATED AT 250 WORDS)
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Xu S, Brenner B, Yu LC. State-dependent radial elasticity of attached cross-bridges in single skinned fibres of rabbit psoas muscle. J Physiol 1993; 465:749-65. [PMID: 7693922 PMCID: PMC1175457 DOI: 10.1113/jphysiol.1993.sp019704] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
1. In a single skinned fibre of rabbit psoas muscle, upon attachment of cross bridges to actin in the presence of ADP or pyrophosphate (PPi), the separation between the contractile filaments, as determined by equatorial X-ray diffraction, is found to decrease, suggesting that force is generated in the radial direction. 2. The single muscle fibres were subjected to compression by 0-8% of dextran T500. The changes in lattice spacings by dextran compression were compared with changes induced by cross-bridge attachment to actin. Based on this comparison, the magnitude and the direction of the radial force generated by the attached cross-bridges were estimated. The radial cross-bridge force varied with filament separation, and the magnitude of the radial cross-bridge force reached as high as the maximal axial force produced during isometric contraction. 3. One key parameter of the radial elasticity, i.e. the equilibrium spacing where the radial force is zero, was found to depend on the ligand bound to the myosin head. In the presence of ADP, the equilibrium spacing was 36 nm. In the presence of MgPPi the equilibrium spacing shifted to 35 nm and Ca2+ had little effect on the equilibrium spacing. 4. The equilibrium spacing was independent of the fraction of cross-bridges attached to actin. The fraction of cross-bridges attached in rigor was modulated from 100% to close to 0% by adding up to 10 mM of ATP gamma S in the rigor solution. The lattice spacing remained at 38 nm, the equilibrium spacing for nucleotide-free cross-bridges at mu = 170 mM. 5. Radial force generated by cross-bridges in rigor at large lattice spacings (38 nm < or = d10 < or = 46 nm) appeared to vary linearly with lattice spacing. 6. The titration of ATP gamma S to fibres in rigor provided a correlation between the radial stiffness of the nucleotide-free cross-bridges and the equatorial intensities. The relation between the equatorial intensity ratio I11/I10 and radial stiffness appeared to be approximately linear. 7. The fibres under different conditions showed a wide range of radial stiffness, which was not proportional to the apparent axial stiffness of the fibre. If the apparent axial stiffness is a measure of the fraction of cross-bridges bound to actin, it follows that the radial elastic constant is state dependent; or vice versa.(ABSTRACT TRUNCATED AT 400 WORDS)
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1307
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Yang L, Chen D, Xu S, Yang T. [Helicobacter pylori associated gastritis: a primary study of ammonia and urea in gastric juice and mucus in gastric mucosa]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1993; 24:216-8. [PMID: 8244308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The mucosa of 46 patients with histological chronic gastritis were cultured for helicobacter pylori (HP) and the ammonia and urea in their gastric juice were also determined. The results showed the average ammonia concentration (1.22 +/- 0.23 mmol/L) in HP positive patients was higher than that of HP negative patients (0.72 +/- 0.25 mmol/L), (P < 0.05). But the average urea concentration (0.45 +/- 0.29 mmol/L) in HP positive patients was lower than that of HP negative patients (2.71 +/- 1.20 mmol/L), (P < 0.05). The higher the level of ammonia stands, the more severe the gastritis is. (rs = 0.556). On the other hand, the quantity of mucus was elevated in 18 patients among 28 patients with HP eradicated by drug treatment, which was significantly different from the patients with HP not eradicated. It is suggested that the epithelium of gastric mucosa and the mucus are the chief components of the gastric mucosa barrier; the presence of HP increases ammonia, and thus damages the gastric epithelium and reduces the quantity of mucus. Consequently, the protective gastric mucosa barrier is damaged, and then comes the liability to HP-associated gastritis.
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1308
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Gaskin F, Finley J, Fang Q, Xu S, Fu SM. Human antibodies reactive with beta-amyloid protein in Alzheimer's disease. J Exp Med 1993; 177:1181-6. [PMID: 8459212 PMCID: PMC2190957 DOI: 10.1084/jem.177.4.1181] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Four human B cell lines established by Epstein-Barr viral transformation of B cells from a patient with a clinical diagnosis of Alzheimer's disease (AD) were found to secrete antibodies that react with plaques and cerebrovascular blood vessels in AD brain in a staining profile characteristic of beta-amyloid protein (beta-AP) in AD brain. Two of these antibodies were shown to be reactive with a rare plaque in a normal brain. In these studies, immunofluorescence and avidin-biotin complex immunoperoxidase methodology were used to determine antibody reaction, and thioflavine S was used to double label amyloid and neurofibrillary tangles. The four antibodies also reacted with neurons in normal and AD brain. Absorption studies, dot immunoblots, and enzyme-linked immunosorbent assays with beta-amyloid peptides 1-28 (beta-A1-28) and 1-40 (beta-A1-40) indicate the major determinant of the reactive epitope is located in the region of amino acids 1-28 of beta-AP. However, inhibition studies demonstrate a significant contribution to the antigenic determinant by the 29-40 region of the beta-A1-40. These antibodies represent the first human autoantibodies against beta-AP. The pathological significance of these autoantibodies is discussed.
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1309
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Liu W, Su Z, Wang L, Xu S, Chen Q, Zhang Z. [The number, distribution and effects of interleukin-2 receptor and CD4 antigens in benign and malignant lymphoproliferative diseases]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1993; 24:13-17. [PMID: 8340084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
An analysis of immunophenotypes was made in benign and malignant lymphoproliferative diseases (35 cases) and short cultured lymphocytes of chronic tonsillitis (15 cases). The number, distribution and variation of interleukin-2 receptor (IL-2R, CD25) and CD4 positive cells in the above lesions were studied. The results showed that (1) there were more or less IL-2R+ and CD4+ cells presented in the tissues of benign lymphoproliferative lesions; (2) IL-2R antigen was also presented in some tumor and non-tumor cells with CD4+ reaction but it was not found in the cells with CD1+ or/and CD8+ reactions; (3) IL-2R and CD4 antigens were expressed in the proliferated lymphocytes stimulated by PHA. Although IL-2R antigen is not a specific marker to certain types of lymphocytes, it has some relations with immunophenotypes of lymphocytes. The functions and effects of IL-2, IL-2R and helper T lymphocytes were also discussed.
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1310
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Zhang S, Liu W, Li G, Xu S, Bu H, Qin Z, Li F, Lei L. [A clinicopathological and immunohistochemical study of 49 cases of necrotizing lymphadenitis]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1993; 24:23-6. [PMID: 8340086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A clinicopathological and immunohistiochemical study of 49 cases of necrotizing lymphadenitis was made. Twenty-four patients were male and twenty-five female with the M:F ratio of 0.96:1. The patients ranged in age from 9 to 62 years with a mean of 26. Forty-nine patients had superficial lymphadenopathy, and twenty-two were accompanied by fever. The results also showed that there was multifoci necrosis present in the involved lymph nodes, particularly in the cortex or/and paracortex, with variable numbers of small lymphocytes, immunoblasts, histocytes and phagocytes, the latter with phagocytized nuclear debris derived from necrotizing T lymphocytes. However, granulocytes and plasmacytes were generally absent, and B lymphocytes rare. The pathogenesis of this disease remains unknown and the pathogen has not been found by Gram, Giemsa, PAS, Ziehl-Neelsen and Warthin-Starry stain. The diagnosis, differential diagnosis and etiology of this disease are discussed. We support the suggestion that this entity be called "Kikuchi-Fujimoto's disease" rather than "Histiocytic necrotizing lymphadenitis".
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1311
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Xu S, Shi F, Shen W, Lin J, Wang Y, Lin B, Qian C, Ye P, Fu L, Shi Y. Vaccination of bovines against Schistosomiasis japonica with cryopreserved-irradiated and freeze-thaw schistosomula. Vet Parasitol 1993; 47:37-50. [PMID: 8493766 DOI: 10.1016/0304-4017(93)90174-l] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Four laboratory tests and one field trial with cryopreserved irradiated (CI) schistosomula vaccine and a freeze-thaw (F/T) vaccine against bovine Schistosomiasis japonica were carried out in 1979 and 1980 with the following results: (1) Single intradermal vaccination in buffalo calves each with 10,000 20 krad CI Schistosomula plus 1 ml BCG gave 62% worm reduction (P < 0.05). Using the same protocol 55% worm reduction (P < 0.01) was obtained in cattle. (2) Buffalo calves immunized twice, at a 1.5 month interval, with 10,000 and 20,000 CI schistosomula, respectively, resulted in a worm reduction 65%. (3) In a preliminary field trial with 10,000 CI schistosomula plus 1 ml BCG resulted in a worm reduction of 53% in buffalo calves. (4) Intradermal vaccination of 30,000 F/T schistosomula with 1 ml BCG was also tried in cattle and revealed a worm reduction of 57% but increasing the number of vaccinations did not improve the protective effect. (5) Evidence regarding the effects of immunization with CI vaccine in buffaloes and F/T vaccine in cattle, on the number of eggs and miracidia and that of female worms themselves was obtained. (6) Immune responses, cellular and humoral, elicited in buffaloes vaccinated with CI schistosomula were detected by means of Lymphocyte Transformation Assay and Enzyme Linked Immunosorbent Assay.
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Resnick D, Freedman NJ, Xu S, Krieger M. Secreted extracellular domains of macrophage scavenger receptors form elongated trimers which specifically bind crocidolite asbestos. J Biol Chem 1993; 268:3538-45. [PMID: 8381434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Macrophage scavenger receptors, which have been implicated in the development of atherosclerosis and other macrophage-mediated events, are trimeric integral membrane glycoproteins whose extracellular domains have been predicted to include alpha-helical coiled-coil, collagenous and globular structures. To elucidate further the structural and functional properties of these receptors, we generated transfected Chinese hamster ovary cells which express secreted extracellular domains of the type I and type II bovine scavenger receptors and developed a solid-phase bead-binding assay to assess their ligand-binding properties. The secreted receptors exhibited the distinctive high-affinity, broad polyanionic ligand-binding specificity and the pH dependence of binding which characterize the membrane-anchored cell-surface forms of the receptors. Both the type I and type II secreted receptors were trimeric glycoproteins comprising disulfide-linked dimers and noncovalently associated monomers. Gel filtration and glycerol-gradient centrifugation established that the type II trimers were highly elongated and did not associate into higher order oligomers at the low concentrations used in these experiments. Crocilodite asbestos, which is phagocytosed by alveolar macrophages and can cause asbestosis and mesothelioma, bound efficiently to secreted type I receptors and less well to the type II receptors. This binding was specific in that it was competed by a variety of well established scavenger receptor ligands but not by negative controls. These studies have identified a new type of insoluble scavenger receptor ligand, and have raised the possibility that scavenger receptors may play a role in mediating the physiological and pathological interactions of inspired particles with alveolar macrophages.
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1313
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Resnick D, Freedman N, Xu S, Krieger M. Secreted extracellular domains of macrophage scavenger receptors form elongated trimers which specifically bind crocidolite asbestos. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)53728-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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1314
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Huang Z, Chen S, Zhang G, Xu S, Huang W, Han Y, Du X. Protective effects of berberine and phentolamine on myocardial reoxygenation damage. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1992; 7:221-5. [PMID: 1364032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
The protective effects of berberine and phentolamine against anoxia and reoxygenation damage in isolated rat hearts have been investigated. Incorporation of berberine (24.5 mumol/L) in both anoxic and aerobic perfusion media resulted in a significant reduction of CPK release during the reoxygenation period, and the ultrastructural damage was reduced as compared with the control group; the myocytes in the berberine-treated group displayed mild intracellular edema, well-registered myofibrils without contracted bands, and swollen mitochondria with partially broken cristae but without dense bodies. Berberine did not inhibit calcium and sodium accumulation or magnesium and potassium loss. Treatment with phentolamine (6.6 mumol/L), an alpha-adrenoceptor antagonist, had similar effects, though the CPK release profile was shifted to the right and downwards. These results suggest that although berberine and phentolamine have some beneficial effects on myocardial reoxygenation injury, they may not abolish the injury. Therefore alpha-adrenoceptor stimulation may not be the major mechanism behind the injury.
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1315
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Russell DG, Xu S, Chakraborty P. Intracellular trafficking and the parasitophorous vacuole of Leishmania mexicana-infected macrophages. J Cell Sci 1992; 103 ( Pt 4):1193-210. [PMID: 1487496 DOI: 10.1242/jcs.103.4.1193] [Citation(s) in RCA: 130] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The continued success of Leishmania as an intramacrophage parasite is dependent on its ability to survive within an acidic intracellular compartment, resist degradation by lysosomal hydrolases, exploit the host cell as a source of nutrients, and avoid the macrophage's antigen-presenting capabilities. All these requirements are dependent on the properties of the parasitophorous vacuole in which Leishmania resides. This study shows that the vacuole possesses membrane proteins characteristic of a lysosome, and has MHC class II molecules. The trafficking of a variety of endocytic markers supports this finding. However, a temporal study up to 14 days post-infection indicates that, as it matures, the vacuole gains mannose 6-phosphate receptor, and becomes more accessible to endocytosed ligand, suggesting that the vacuole has functionally translocated from a lysosomal to late endosomal compartment. Endocytosed material was detected in the flagellar pocket and inside the amastigote, demonstrating parasite uptake of intra-vacuolar material. Careful analysis of amastigotes suggests that they avoid antigen presentation by their host cell by limiting the release of potential antigens. These findings significantly extend our understanding of the mechanisms employed by Leishmania to ensure its survival in the macrophage.
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Huang M, Yao J, Xu S, Meng C. E.p.r. evidence of the unusual coordinational environment for Mo5+ in SAPO-5 molecular sieves. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0144-2449(92)90054-s] [Citation(s) in RCA: 13] [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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Abstract
Because of their short dynamical lifetimes, the population of near-Earth asteroids (NEAs) must be resupplied. Two sources have been hypothesized: main-belt asteroids and extinct comet nuclei. The difficulty of making physical measurements for similar sized (diameter D less than 5 kilometers) main-belt asteroids and comet nuclei has limited comparative tests for distinguishing between these alternatives. A new survey of physical properties for D < 5 kilometers main-belt asteroids reveals that their spin rate and shape distributions are similar to those of NEAs, as is fully consistent with a main-belt origin for most NEAs. Physical data on comet nuclei are limited. If the existing sample is representative of the comet population, analysis of the asteroid and comet samples constrains the fraction of comet nuclei to between 0 and 40 percent of the total NEA population.
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1318
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Xu S, Roychowdhury S, Gaskin F, Epstein DL. Ethacrynic acid inhibition of microtubule assembly in Vitro. Arch Biochem Biophys 1992; 296:462-7. [PMID: 1352959 DOI: 10.1016/0003-9861(92)90598-q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Ethacrynic acid (ECA) is a sulfhydryl reactive diuretic drug. Recent studies show that ocular administration of ECA may have potential efficacy for treatment of glaucoma. ECA affects cell shape in cultured cells from the eye outflow pathway and the microtubule system is disrupted. We have studied the effect of ECA on microtubule protein (MTP) (tubulin and microtubule-associated proteins) and purified tubulin assembly. Fifty percent inhibition of MTP (1.8 mg/ml) assembly was found at 70 microM ECA in buffer and 410 microM ECA in 30% glycerol in buffer. If all sulfhydryl groups were attributed to tubulin, then approximately two sulfhydryls were blocked at 50% inhibition. Tubulin (2 mg/ml) assembly showed 50% inhibition at 175 microM ECA and approximately 2 sulfhydryl groups were lost. Increasing ECA preincubation times (0-60 min) with tubulin showed that the longer the preincubation time, the longer the lag time, and the slower the rate of assembly and that the percentage of inhibition was proportional to the ECA preincubation time. The number of blocked sulfhydryls also increased with preincubation time. Approximately two sulfhydryls were blocked at 50% inhibition of assembly. The critical concentration for assembly increased twofold when tubulin was preincubated with 0.1 mM ECA, suggesting a loss of active tubulin. Fifty percent inhibition of taxol-induced MTP and tubulin assembly occurred at 190 and 280 microM ECA, respectively, with 3.6 to 3.8 sulfhydryls blocked, respectively. Taxol protects microtubules from disassembly by ECA, suggesting that the ECA binding key sulfhydryls are blocked in the microtubule. These results suggest that ECA reacts slowly with tubulin and blocks sulfhydryl groups important for assembly. Microtubule-associated proteins and glycerol protect the sulfhydryls and so more ECA is necessary to inhibit assembly. Since the number of blocked sulfhydryls is greater at 50% inhibition for taxol-induced microtubules, sulfhydryl blocked tubulin incompetent to assemble under normal conditions may be induced to do so with taxol.
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Jia Y, Li T, Li X, Xu S, Pan M. [Thin layer chromatography for identification of 9 species of traditional Chinese medicine in baihe gujin tang granules]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1992; 17:410-1, 445. [PMID: 1445644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Baihe Gujin Tang granules are mainly composed of nine species of traditional Chinese medicine and other admixtures, so the composition is very complex. In order to confirm the presence of each traditional Chinese medicine in the preparation, a thin layer chromatographic method was developed successfully for analysis of Scrophulariae, Platycodon, Paeoniae and Glycyrrhizae.
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Xu S. Application of the slotted quartz tube in flow-injection flame atomic-absorption spectrometry. Talanta 1992; 39:581-7. [DOI: 10.1016/0039-9140(92)80064-k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/1991] [Revised: 11/19/1991] [Accepted: 11/19/1991] [Indexed: 10/18/2022]
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1321
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Muir W, Nyquist WE, Xu S. Alternative partitioning of the genotype-by-environment interaction. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 1992; 84:193-200. [PMID: 24203047 DOI: 10.1007/bf00224000] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/1991] [Accepted: 10/17/1991] [Indexed: 05/25/2023]
Abstract
Alternative methods for partitioning the genotype-by-environment interaction, for an arbitrary number of genotypes or environments, were examined. Partitioning of the interaction is important in order to determine the nature of the interaction. Two methods of partitioning were examined; both separated the interaction into two types: (1) due to heterogeneous variances or (2) due to imperfect correlations. Method 1 was based on heterogeneity among environments in the scaling of differences among genotypes. Method 2 was based on heterogeneity among genotypes in the scaling of differences among environments. Any remaining interaction arises from deviations from the perfect positive correlation of genotypic rankings among environments (Method 1) or of environmental rankings among genotypes (Method 2). Method 1 is more appropriate for random genotypes that are to be tested in either fixed or random environments. With Method 1, the interactions that arise mainly from heterogeneity of genotypic scaling among environments are generally unimportant. However, if environments are fixed and interactions are mainly due to imperfect correlations of rankings, specialized lines may be indicated for each environment. Method 2 is more useful in evaluating fixed genotypes for sensitivity to random environments. A partitioning of the interaction into that due to the type of interaction within each genotype was shown to be useful in that situation.
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1322
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Lin G, Xu S. [A new method of enveloping volatile oils in Chinese medicinal herbs with beta-cyclodextrin]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1992; 17:283-5, 320-inside backcover. [PMID: 1418563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A comparison has been made of the enveloping rate of volatile oil by three different methods with beta-cyclodextrin. The result indicates that the saturated water solution enveloping method is very close to the gas-liquid enveloping method, P greater than 0.05, but the liquid-liquid enveloping method is apparently higher than the saturated water solution enveloping method, P less than 0.01.
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Feng F, Xu S. [Optimization of preparing technology for qiju dihuang oral liquid by orthogonal method]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1992; 17:282-3, 320. [PMID: 1418562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
L9(3)4 orthogonal experiment was performed to improve the clarity of Qiju Dihuang Oral Liquid. The result shows that the optimum pretreatment technology for the liquid includes alcohol concentration 75%, liquid pH 4.2 freezing temperature 3 degrees C and freezing time 48 hours.
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Xu S, Arbeit RD, Lee JC. Phagocytic killing of encapsulated and microencapsulated Staphylococcus aureus by human polymorphonuclear leukocytes. Infect Immun 1992; 60:1358-62. [PMID: 1548061 PMCID: PMC257004 DOI: 10.1128/iai.60.4.1358-1362.1992] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Phagocytosis by human polymorphonuclear leukocytes (PMNs) is an important host defense against infections caused by Staphylococcus aureus. Using an in vitro assay, we compared the opsonic requirements for phagocytic killing of prototype strains of encapsulated (type 1) and microencapsulated (type 5 and type 8) S. aureus by human PMNs. More than 85% of broth-grown, logarithmic-phase type 5 and 8 S. aureus organisms were killed by PMNs incubated with fresh normal human, rabbit, or guinea pig serum with complement activity. Under similar conditions, the highly encapsulated type 1 strain was not killed. Both encapsulated and microencapsulated strains were opsonized for phagocytosis by heat-inactivated serum raised in rabbits to killed bacteria. Opsonization by homologous serum was required for phagocytosis of the type 1 strain. In contrast, microencapsulated type 5 and 8 S. aureus organisms were killed by heat-inactivated rabbit serum raised to type 5, type 8, or nonencapsulated isolates; this result suggested that antibodies to the capsule or to cell wall components other than the capsule could opsonize these organisms for phagocytosis. The specificity of the assay was confirmed with capsule type 5-specific monoclonal antibodies, which were opsonic only for the type 5 S. aureus isolate. These studies indicate that, unlike the highly encapsulated type 1 strain, broth-grown microencapsulated S. aureus strains do not resist opsonophagocytic killing in vitro by normal serum.
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Xu S, Muir WM. Selection index updating. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 1992; 83:451-458. [PMID: 24202591 DOI: 10.1007/bf00226533] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/1990] [Accepted: 07/18/1991] [Indexed: 06/02/2023]
Abstract
When traits become evident at different ages or there are large differences in the costs of measuring various traits, selection by independent culling levels may give a higher aggregate economic return than index selection because not all traits need to be measured on all individuals. The problems with optimum independent culling selection is that general solutions are not possible and numerical integration is needed for specific cases. Recently, Xu and Muir (1991) developed a new independent culling level procedure by use of orthogonal transformation of the original characters. With their procedure, explicit solutions for optimum truncation points are possible without numerical integration. As such, the procedure is proficient for any number of stages, and generalized theoretical comparisons of alternative breeding strategies are possible. However, their procedure was limited to the case where selection is for one character at each stage. In this paper, our previous results are extended to the general case of multi-stage index selection, called selection index updating. This procedure is called selection index updating because as traits become available in latter stages, each subsequent index contains all of the traits available up to that stage.The procedure is to develop sequential indices for each stage such that correlations among indices at different stages are zero. Optimum culling points are obtained for the updating procedure by using Xu and Muir's (1991) iterative equations. Due to the property of orthogonality of the updated indices, aggregate gain can be partitioned into gains due to various stages of selection. Partitioning of aggregate economic gain is useful to breeders who desire to adjust individual trait selection intensity based on facilities available at that stage. Methods are discussed to modify the procedure to obtain maximum aggregate economic return per unit of cost associated with obtaining measures on each trait. An application of multi-stage selection is demonstrated using a set of data for Rhode Island Red layer type chickens. A second example demonstrates the use of multi-stage selection optimized with respect to aggregate economic gain and costs associated with obtaining measurements.
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