101
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You X, Tan S. [A study on activity of beta-glucuronidase in serum and secretion from upper respiratory tract in patients with head and neck malignant tumors]. Zhonghua Er Bi Yan Hou Ke Za Zhi 1998; 31:181-4. [PMID: 9639722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Beta-glucuronidase (beta-GD) activity in serum and upper respiratory tract (URT) secretion in patients with head and neck malignant tumors (HNMT) was studied. Subjects included 40 HNMT patients, 40 healthy volunteers and 40 patients with benign tumors of the head and neck region. The results showed that there was no statistically significant difference of serum beta-GD level among the three groups. The same was true for URT secretion between the normal control and benign tumor groups. beta-GD level in URT secretion was higher in HNMT group than in other groups (P < 0.001). Using healthy subjects' average beta-GD level plus two standard difference as positive standard, the sensitivity, reliability and specificity of the test were 85.0%, 92.5% and 100% respectively. beta-GD levels were higher in patients with advanced tumors and metastases. One year follow-ups of six patients showed that beta-GD level change in URT secretion was in accordance with clinical manifestations. These results suggest that assay of beta-GD level in URT secretion can be used as a valuable supplimental parameter in early diagnosis of HNMTs, their clinical staging, evaluation of therapeutic effectiveness and detection of recurrence and metastases. In addition, this method has the advantage of easy, prompt, result specificity, sensitivity and reliability.
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Affiliation(s)
- X You
- Tongji Hospital, Tongji Medical University, Wuhan
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102
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103
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You X, Schinazi RF, Arrowood MJ, Lejkowski M, Juodawlkis AS, Mead JR. In-vitro activities of paromomycin and lasalocid evaluated in combination against Cryptosporidium parvum. J Antimicrob Chemother 1998; 41:293-6. [PMID: 9533476 DOI: 10.1093/jac/41.2.293] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Using a chemiluminescence immunoassay, paromomycin and lasalocid were shown to inhibit Cryptosporidium parvum growth in Madin-Darby canine kidney cells in a concentration-dependent manner. The median effective concentrations (EC50s) for paromomycin and lasalocid were 1184 mg/L and 0.4 mg/L, respectively. Neither drug was cytotoxic to host cells at concentrations up to five times their EC50s. Drug combination studies were conducted and the resulting data were analysed by the median-effect principle and combination index method. Statistically significant synergy was observed when combinations of paromomycin and lasalocid were used at ratios of 5000:1 and 2500:1. A possible mechanism for synergy is discussed.
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Affiliation(s)
- X You
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
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104
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Gao Q, Cui Y, You X. [Microwave operation of angiofibroma of nasopharynx under nasal endoscope]. Lin Chuang Er Bi Yan Hou Ke Za Zhi 1997; 11:505-6. [PMID: 10323020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Two patients with angiofibroma of nasopharynx were treated with microwave operation under nasal endoscope in our hospital. This operation could reduce the amount of blood less than operations by palatine apporach and nose apporach apprentently. So the blood transplantation was avoid. Meanwhile, it lessen somatopsychic pain and ecnomical burden. Because of the clean and clear operation field under nasal endoscope, the tumor could be removed completely and correctly. Then, the possibility of relapse was reduced.
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Affiliation(s)
- Q Gao
- Department of Otolaryngology, Tongji Hospital, Tongji Medical University, Wuhan
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105
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Xiao T, Jiang Y, You X. [The association of HLA-DR4 gene subtypes with Vogt-Koyanagi-Harada syndrome]. Zhonghua Yan Ke Za Zhi 1997; 33:268-71. [PMID: 10451958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
OBJECTIVE To investigate the association of HLA-DR4 subtypes with Vogt-Koyanagi-Harada (VKH) syndrome and to clarify immune genetic mechanism underlying the susceptibility/resistance to VKH syndrome. METHODS HLA-DR4 alleles of 54 patients with VKH and 106 healthy controls were amplified and subtyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS A selective amplification of the DR4 alleles of 263 bp was higher in patients with VKH than in the controls. The frequency of DR4-DRB1 alleles was 70% (38/54) in VKH group and was 19% (20/106) in the control group, relative rish (RR) = 10.21, P < 0.005. The genotyping of DR4 alleles showed that DRB1 * 0405 was more frequent in VKH group (35/38, 92%) than in the control group [6/20, 30%, RR = 27.2, P = 0.0,000,017, corrected pvalue (Pc) = 0.0,000,103]. CONCLUSIONS It is suggested that DRB1 * 0405 be a susceptible subtype to VKH and the specific amino acid residue Ser (serine) at position 57 play an important role in the development of VKH syndrome. The molecular biological technique we used may be useful in studying the immunogenetic mechanism of VKH.
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Affiliation(s)
- T Xiao
- Department of Ophthalmology, Second Affiliated Hospital, Hunan Medical University, Changsha
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106
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107
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Abstract
The UL5, UL8, and UL52 genes of herpes simplex virus type 1 encode a multisubunit assembly that possesses primase, DNA helicase, and DNA-dependent nucleoside triphosphatase activities. A subassembly consisting of the UL5 and UL52 gene products retains these activities. The nucleoside triphosphatase activity of the UL5/UL52 subassembly is strongly stimulated by both homo- and heteropolymeric single-stranded DNA. Double-stranded DNA has little ability to stimulate the ATPase activity. The subassembly binds both double and single-stranded DNA. Nucleotides are not required for DNA-binding. The minimum length of single-stranded DNA that is bound and that stimulates enzymatic activity is about 12 nucleotides. The kinetic parameters of the ATPase activity of the subassembly are affected by the length of the oligonucleotide coeffector. The Km decreases as the coeffector length is increased up to a length of about 20 nucleotides and then remains independent of coeffector length. The first order rate constant for ATPase activity exhibits a quasihyperbolic dependence on the length of the DNA coeffector and is maximal for coeffectors of 20 nucleotides and longer.
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Affiliation(s)
- S Healy
- Department of Biochemistry, University of Arizona, Tucson, Arizona 85721-0088, USA
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108
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Rothman N, Hayes RB, Zenser TV, DeMarini DM, Bi W, Hirvonen A, Talaska G, Bhatnagar VK, Caporaso NE, Brooks LR, Lakshmi VM, Feng P, Kashyap SK, You X, Eischen BT, Kashyap R, Shelton ML, Hsu FF, Jaeger M, Parikh DJ, Davis BB, Yin S, Bell DA. The glutathione S-transferase M1 (GSTM1) null genotype and benzidine-associated bladder cancer, urine mutagenicity, and exfoliated urothelial cell DNA adducts. Cancer Epidemiol Biomarkers Prev 1996; 5:979-83. [PMID: 8959320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Multiple studies in the general population have suggested that subjects with the glutathione S-transferase M1 (GSTM1)-null genotype, who lack functional GSTM1, are at higher risk for bladder cancer. To evaluate the impact of the GSTM1-null genotype on bladder cancer caused by occupational exposure to benzidine and to determine its influence on benzidine metabolism, we carried out three complementary investigations: a case-control study of bladder cancer among workers previously exposed to benzidine in China, a cross-sectional study of urothelial cell DNA adducts and urinary mutagenicity in workers currently exposed to benzidine in India, and a laboratory study of the ability of human GSTM1 to conjugate benzidine and its known metabolites in vitro. There was no overall increase in bladder cancer risk for the GSTM1-null genotype among 38 bladder cancer cases and 43 controls (odds ratio, 1.0; 95% confidence interval, 0.4-2.7), although there was some indication that highly exposed workers with the GSTM1-null genotype were at greater risk of bladder cancer compared to similarly exposed workers without this allele. However, the GSTM1 genotype had no impact on urothelial cell DNA adduct and urinary mutagenicity levels in workers currently exposed to benzidine. Furthermore, human GSTM1 did not conjugate benzidine or its metabolites. These results led us to conclude that the GSTM1-null genotype does not have an impact on bladder cancer caused by benzidine, providing a contrast to its association with elevated bladder cancer risk in the general population.
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Affiliation(s)
- N Rothman
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland 20892, USA
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109
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You X, Arrowood MJ, Lejkowski M, Xie L, Schinazi RF, Mead JR. In vitro evaluation of anticryptosporidial agents using MDCK cell culture and chemiluminescence immunoassay. J Eukaryot Microbiol 1996; 43:87S. [PMID: 8822878 DOI: 10.1111/j.1550-7408.1996.tb05013.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- X You
- Dept. of Pediatrics, Emory Univ. School of Medicine, Atlanta, GA 30322, USA
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110
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Bonafonte MT, Lloyd RM, Garmon KD, You X, Arrowood MJ, Schinazi RF, Mead JR. Cloning and expression of sporozoite and oocyst Cryptosporidium parvum recombinant proteins. J Eukaryot Microbiol 1996; 43:83S. [PMID: 8822875 DOI: 10.1111/j.1550-7408.1996.tb05010.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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112
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You X, Arrowood MJ, Lejkowski M, Xie L, Schinazi RF, Mead JR. A chemiluminescence immunoassay for evaluation of Cryptosporidium parvum growth in vitro. FEMS Microbiol Lett 1996; 136:251-6. [PMID: 8867380 DOI: 10.1111/j.1574-6968.1996.tb08057.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
A chemiluminescence immunoassay (CLIA) was developed to detect Cryptosporidium parvum growth in Madin-Darby canine kidney (MDCK) cell cultures. Optimal results were obtained when MDCK cells were plated at a density of 1 x 10(4) cells/well (96-well plate) and maintained as a monolayer for 4 days prior to infection with 2 x 10(4) parasites/well. Two compounds (paromomycin and maduramicin) were evaluated and shown to have selective activity against C. parvum in a dose-dependent manner. There was excellent correlation between CLIA and immunofluorescence assay when assessing anti-C. parvum agents in MDCK cells. CLIA offers advantages over conventional enzyme-linked immunosorbent assay and immunofluorescence assay methods in that it is more sensitive and efficient. The combination of CLIA and MDCK culture provides an efficient tool for evaluating potential anti-cryptosporidial compounds prior to testing in animal models.
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Affiliation(s)
- X You
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
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113
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Abstract
Despite the evaluation of over 100 antimicrobial drugs, the diarrheal disease cryptosporidiosis has remained refractory to treatment. We report the evaluation of five dinitroaniline herbicides including trifluralin, profluralin, nitralin, pendimethalin, and fluchloralin for anticryptosporidial activity in an in vitro cultivation model of Cryptosporidium parvum. All five compounds exhibited significant anticryptosporidial activities with no corresponding evidence of toxicity. The most active compound was pendimethalin with an IC50 of 0.19 microM while nitralin was the least active with an IC50 of 4.5 microM. These compounds should be evaluated further in an animal model of cryptosporidiosis.
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Affiliation(s)
- M J Arrowood
- National Center for Infectious Diseases, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Services, Atlanta, GA 30341-3724, USA. mja0/ciddpd2.em.cdc.gov
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114
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Zheng Y, Liu D, Feng D, Tang H, Li Y, You X. An animal study on transmission of hepatitis B virus through mosquitoes. Chin Med J (Engl) 1995; 108:895-7. [PMID: 8728939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Three gena of mosquitoes were fed with human blood infected with hepatitis B virus (HBV) artificially. When blood in the stomach was completely digested, mosquitoes were used to bite monkeys Tupaia Belangeri. A month after biting, venous blood samples were taken from the monkeys to detect serum HBsAg, HBeAg, Anti-HBs and Anti-HBc. Among 29 test monkeys, 9 were HBV infective serum markers positive. In 4 of 16 test monkey liver biopsies, acute inflammatory changes were found with Hematoxylin-Eosine staining. In the hepatic cells, HBsAg and HBcAg were detected by immunohistochemical double-labeling assays, and HBV-DNA was also positive by in situ hybridization in monkey liver sections. These results provided an evidence for the possibility of transmission of HBV through mosquitoes and suggest its epidemiological significance in mosquito infested areas.
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Affiliation(s)
- Y Zheng
- Second Affiliated Hospital, Hunan Medical University, Changsha
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115
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You X, Bergmanson JP, Zheng XM, MacKenzie IC, Boltz RL, Aquavella JV. Effect of Corticosteroids on Rabbit Corneal Keratocytes After Photorefractive Keratectomy. J Refract Surg 1995; 11:460-7. [PMID: 8624830 DOI: 10.3928/1081-597x-19951101-12] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND To determine the corticosteroid effect on the activity and repopulation of keratocytes after photorefractive keratectomy (PRK). METHODS A 193-nm excimer laser (VISX Twenty/Twenty) created a central ablation depth of 22 microns (diameter:5 nm) on 22 corneas of 16 albino rabbits. Two ablated eyes were examined 6 hours following PRK. Twelve eyes received no postoperative corticosteroids and eight were treated with topical fluoromethalone for 3 months. Corneas were examined 1, 3, 6, and 12 months after PRK by immunofluorescence and transmission electron microscopy. RESULTS Corticosteroids reduced haze (p=0.02), but all corneas (treated or untreated) cleared 6 months after PRK. Keratocytes were absent from the anterior 100 microns of the stroma 6 hours after PRK. However, the number and activity of keratocytes were significantly greater in this area in untreated corneas at 1 month and then gradually decreased. By 6 and 12 months, the number of keratocytes approached controls. Treated corneas had fewer keratocytes than either controls or untreated eyes (p<0.01) and by 3 months, a subepithelial acellular zone of 30 to 50 microns thickness appeared and persisted until at last 12 months after PRK. CONCLUSIONS Corticosteroids have a transient effect in reducing haze and seem to inhibit keratocyte movement, leading to an acellular subepithelial region beneath the ablated area.
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Affiliation(s)
- X You
- University of Houston, College of Optometry 77204-6052, USA
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116
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117
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Mead JR, You X, Pharr JE, Belenkaya Y, Arrowood MJ, Fallon MT, Schinazi RF. Evaluation of maduramicin and alborixin in a SCID mouse model of chronic cryptosporidiosis. Antimicrob Agents Chemother 1995; 39:854-8. [PMID: 7785984 PMCID: PMC162642 DOI: 10.1128/aac.39.4.854] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Two polyether ionophores, maduramicin and alborixin, were evaluated for anticryptosporidial activity in a severe combined immune deficient (SCID) mouse model of cryptosporidiosis. Groups of SCID mice were inoculated with 10(6) oocysts of bovine origin by oral gavage. Maduramicin or alborixin was administered beginning 4 weeks postinfection at 3 mg/kg of body weight per day. Maduramicin treatment resulted in a 96% reduction in fecal parasite load over the 3-week treatment period (P < 0.003). This reduction correlated with decreases in tissue parasite loads observed in histological sections of the small intestine (P < 0.000002) and the colon (P < 0.000006). A significant decrease in oocyst shedding was also observed after a 3-week treatment with alborixin (71% reduction, P < 0.01). Maduramicin was also evaluated in a relapsing model of cryptosporidiosis in which the infection was observed to recur after treatments were discontinued. Some toxicity, as demonstrated by weight loss, was observed with both maduramicin and alborixin. Both drugs exhibited significant anticryptosporidial activities with concomitant moderate toxicity. These polyether ionophores should be valuable as positive controls in compound evaluation studies and as lead compounds for chemical optimization (modification).
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Affiliation(s)
- J R Mead
- Department of Pediatrics, Emory University, Atlanta, Georgia 30022, USA
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118
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Mead JR, Lloyd RM, You X, Tucker-Burden C, Arrowood MJ, Schinazi RF. Isolation and partial characterization of Cryptosporidium sporozoite and oocyst wall recombinant proteins. J Eukaryot Microbiol 1994; 41:51S. [PMID: 7804255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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119
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Wang X, You X. [An analysis of the uneven prevalence of tuberculosis in various areas and regions in China]. Zhonghua Liu Xing Bing Xue Za Zhi 1994; 15:195-8. [PMID: 7834700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This article analyzed the uneven prevalence of tuberculosis in various areas and regions and its trend in China nowadays based on the data of the nationwide epidemiological sampling survey of tuberculosis in 1979 and 1990. The highest prevalence was 25-30 times higher than the lowest among provinces, municipalities and regions. The prevalence in remote areas and regions was significantly higher than that in coastal areas and municipalities. The ratios of the prevalence of pulmonary tuberculosis between cities and countryside were 1:2.4-2.8. Most of the investigation points which had a higher prevalence was located in remote and inland areas. Some minority areas which had higher prevalence resided in the northwest and southwest remote areas. The uneven tuberculosis prevalence in various areas and regions indicated that tuberculosis is still an important public health problem in China at present.
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Affiliation(s)
- X Wang
- Tuberculosis Control Centre, Ministry of Public Health, Beijing
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120
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You X, Mulchinski EA, Agarwal AK. Protection of carbon tetrachloride hepatotoxicity by cinchona alkaloids. Res Commun Chem Pathol Pharmacol 1994; 84:223-32. [PMID: 8091007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Elevated serum enzymes were observed due to all four cinchona alkaloids in male Sprague-Dawley rats after four day treatment. Only a slight effect on bile flow and excretion of phenolphthalein glucuronide in bile was noted. Animals treated with cinchona alkaloid for four days and then receiving CCl4 showed a partial protection against CCl4 induced hepatotoxicity. The levels of serum enzymes were lowered as compared to animals treated with CCl4 alone. Bile flow and excretion of phenolphthalein glucuronide in bile showed a trend of restoration towards control levels. All four cinchona alkaloids probably inhibit microsomal enzymes, thereby, inhibiting the bioactivation of CCl4 and hence reducing the toxicity.
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Affiliation(s)
- X You
- Department of Sciences, John Jay College of CUNY, NY 10019
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121
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Abstract
Cryptosporidial infections in severe combined immune deficient (SCID) mice produce a chronic disease state which in the later stages leads to extraintestinal involvement and hepatic dysfunction. To further characterize the infection dynamics in this model and monitor the changes in the hepatic system, a dose titration of the oocyst inoculum was performed and alkaline phosphatase levels in the sera were assayed. Ten SCID mice per dose were inoculated with 10(3), 10(4), 10(5), 10(6), or 10(7) oocysts. Oocyst shedding in the feces was quantified by microscopic enumeration. Mice inoculated with 10(6) oocysts and those inoculated with 10(7) oocysts demonstrated similar oocyst shedding patterns, but the 10(7)-oocyst group exhibited signs of distress (e.g., weight loss and icterus) earlier. The intensity of the infection increased markedly approximately 14 days postinoculation (p.i.) and continued to increase steadily over the next 6 weeks. Inoculation with lower oocyst doses produced a delay in patency (e.g., it occurred 7 days later with the 10(5)-oocyst inoculum and 14 days later with the 10(4)-oocyst inoculum). Mean serum alkaline phosphatase levels in the 10(7)-oocyst group were more than twice control values at 5 weeks p.i. and continued to increase over the next 8 weeks. Oocyst doses and alkaline phosphatase levels were positively correlated with hepatobiliary colonization (r = 0.71) and liver necrosis (r = 0.65) at 13 weeks p.i. A strong positive correlation between hepatobiliary colonization and liver necrosis at 13 weeks p.i. (r = 0.87) was observed.
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Affiliation(s)
- J R Mead
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia 30022
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122
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Rothman N, Hayes RB, Bi W, Caporaso N, Broly F, Woosley RL, Yin S, Feng P, You X, Meyer UA. Correlation between N-acetyltransferase activity and NAT2 genotype in Chinese males. Pharmacogenetics 1993; 3:250-5. [PMID: 8287063 DOI: 10.1097/00008571-199310000-00004] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Eighty-four healthy Chinese male control subjects derived from an occupation-based case-control study of bladder cancer were evaluated for hepatic N-acetyltransferase activity by dapsone and for NAT2 genotype using allele-specific amplification of peripheral leukocyte DNA by the polymerase chain reaction. Fifty-nine percent of the overall variation in acetylation activity was explained by genotype (p < 0.0001). The remaining variation in acetylation was not associated with dapsone N-hydroxylation activity, age, current smoking status, or weight in the study population, or within any genotype subgroup. Although acetylation activity in the homozygous mutant group did not overlap with the other genotype categories, there was moderate overlap in acetylation between the heterozygous mutant and wildtype groups, and substantial variation in acetylation within them. Considering all subjects with the identical NAT2 genotype as phenotypically similar and all subjects with differing NAT2 genotypes as phenotypically distinct may result in misclassification of metabolic risk factors in epidemiological investigations. As such, it would seem prudent, where possible, to collect both acetylation phenotype and NAT2 genotype data, since the advantages and limitations of these two sources of information complement, and serve to assess the accuracy of each other.
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Affiliation(s)
- N Rothman
- Epidemiology and Biostatistics Program, National Cancer Institute, Bethesda, MD 20892
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123
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Hayes RB, Bi W, Rothman N, Broly F, Caporaso N, Feng P, You X, Yin S, Woosley RL, Meyer UA. N-acetylation phenotype and genotype and risk of bladder cancer in benzidine-exposed workers. Carcinogenesis 1993; 14:675-8. [PMID: 8472331 DOI: 10.1093/carcin/14.4.675] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Several studies in subjects occupationally exposed to arylamine carcinogens have shown increased risks for bladder cancer associated with the slow acetylator phenotype. To follow up these reports, a case-control study of N-acetylation and bladder cancer risk was carried out among subjects occupationally exposed to benzidine, in benzidine dye production and use facilities in China. Thirty-eight bladder cancer cases and 43 controls from these factories were included for study of acetylation phenotype, by dapsone administration, and for polymorphisms in the NAT2 gene, by a polymerase chain reaction (PCR)-based test. In contrast to previous studies, no increase in bladder cancer risk was found for the slow N-acetylation phenotype (OR = 0.3; 95% CI = 0.1-1.3) or for slow N-acetylation-associated double mutations in NAT2 (OR = 0.5; 95% CI = 0.1-1.8). Examination of specific mutations and adjustment for age, weight, city and tobacco use did not alter the results. When examined by level of benzidine exposure in the cases, the bladder cancer risks associated with low (OR = 0.3, 95% CI = 0.0-2.2), medium (OR = 0.7, 95% CI = 0.1-4.5) and high (OR = 0.6, 95% CI = 0.1-3.5) exposure showed no interaction between genotype and benzidine exposure, within the range of exposures experienced by subjects in this study. This study, which is the first to incorporate phenotypic and genotypic analyses, provides evidence that the NAT2-related slow N-acetylation polymorphism is not associated with an increased risk of bladder cancer in workers exposed to benzidine, and may have a protective effect.
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Affiliation(s)
- R B Hayes
- Environmental Epidemiology Branch, National Cancer Institute, Bethesda, MD
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124
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Bi W, Hayes RB, Feng P, Qi Y, You X, Zhen J, Zhang M, Qu B, Fu Z, Chen M. Mortality and incidence of bladder cancer in benzidine-exposed workers in China. Am J Ind Med 1992; 21:481-9. [PMID: 1580253 DOI: 10.1002/ajim.4700210404] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We examined bladder cancer mortality and incidence to 1981 in 1,972 workers employed in benzidine-exposed jobs in Tianjin, Shanghai, and Jilin, China, between 1972 and 1977, and in 1,974 unexposed workers employed during the same time period. In comparison to general population rates, in the benzidine-exposed group the ratio of observed to expected deaths (SMR) was 17.5 (95% C.I.: 7.5-34.5) and the ratio of observed to expected incident cases (SIR) was 25.0 (95% C.I.: 16.9-35.7). No excess was noted in the unexposed group. The 25-fold increase in bladder cancer incidence in the exposed group was related to level of exposure, with the SIR rising from 4.8 for low exposure to 36.2 for medium exposure, and 158.4 for high exposure. Risks were elevated both for producers of benzidine (SIR = 45.7; 95% C.I.: 20.9-86.8) and for users (SIR = 20.9; 95% C.I.: 12.9-32.0) of benzidine dyes. Benzidine-exposed workers who smoked tobacco had a 31-fold risk (95% C.I.: 20.4-46.4), while non-smoking workers had an 11-fold risk (95% C.I.: 3.6-25.8), suggestive of a multiplicative relationship between these two carcinogens.
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Affiliation(s)
- W Bi
- Institute of Occupational Medicine, Chinese Academy of Preventive Medicine, Beijing
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Alyea EC, Liu S, Li B, Xu Z, You X. Structure of a potentially heptadentate tripodal ligand, tris[4-(2-thienyl)-3-aza-3-butenyl]amine. Acta Crystallogr C 1989. [DOI: 10.1107/s0108270189002283] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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