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Wiehe S, Fortenberry JD, Rosenman M, Tu W. P1-S4.09 Validation of the HEDIS measure of sexual activity in adolescents. Br J Vener Dis 2011. [DOI: 10.1136/sextrans-2011-050108.153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Tu W, Batteiger B, Ofner S, Van Der Pol B, Fortenberry D. P1-S1.12 Age-specific incidence of chlamydia, gonorrhoea, and trichomoniasis infection in adolescent women. Br J Vener Dis 2011. [DOI: 10.1136/sextrans-2011-050108.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Xu C, Xu G, Tu W, Wu X, Fang X, Huang T. Heparin and prednisone-associated priapism: two case reports. Andrologia 2011; 43:68-70. [PMID: 21219386 DOI: 10.1111/j.1439-0272.2009.01006.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Priapism is a prolonged penile erection that is not associated with sexual stimulation. In this report, two patients who developed priapism 2-4 h after an oral prednisone and intravenous heparin infusion are described. Low-flow (ischaemic) priapism is usually associated with sickle cell disease, haemoglobinopathies, neoplastic syndrome, anticoagulant therapy (heparin and warfarin), psychotropic medication, sildenafil citrate (Viagra) or idiopathic causes. Here we report two cases of prolonged low-flow priapism induced by heparin and prednisone. Treatments were successfully conducted after the priapism, while the exact mechanism remains unclear.
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Ermel A, Qadadri B, Morishita A, Miyagawa I, Yamazaki G, Weaver B, Tu W, Tong Y, Randolph M, Cramer H, Brown D. Human papillomavirus detection and typing in thin prep cervical cytologic specimens comparing the Digene Hybrid Capture II Assay, the Roche Linear Array HPV Genotyping Assay, and the Kurabo GeneSquare Microarray Assay. J Virol Methods 2010; 169:154-61. [PMID: 20670658 DOI: 10.1016/j.jviromet.2010.07.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 07/13/2010] [Accepted: 07/20/2010] [Indexed: 11/30/2022]
Abstract
Three methods for the detection of HPV DNA were compared in cervical cytologic specimens: the Digene Hybrid Capture II Assay (HC), the Roche Linear Array HPV Genotyping Assay (LA) and the Kurabo GeneSquare Microarray (GS). The main goals of the study were to correlate cytology with HPV detection and to determine agreement between assay pairs for HPV detection. Thin-prep Pap smears were performed and supernates were tested by HC, LA, and GS. For specimens reacting with the HPV 52/33/35/58 probe in the LA assay, type-specific PCR was performed for HPV types 52, 33, 35, or 58. Binomial proportions and kappa coefficients were calculated for agreement between assays. Cytology results and supernatant were available for 202 subjects. HPV detection increased with worsening cytologic abnormality in all three assays. For all cytologic groups, LA and GS detected more HPV (all and oncogenic) than HC. However, for detection of oncogenic HPV types represented in all three assays, differences between assays were less pronounced. The highest agreement was between LA and GS. In four of 12 specimens reacting with the HPV 52/33/35/58 probe in the LA assay but deemed HPV 52-LA-negative using an algorithm provided by the manufacturer, the presence of HPV 52 was confirmed using type-specific HPV 52 PCR. All four of these specimens were also GS-positive for HPV 52.
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Brown CR, Leon ML, Muñoz K, Fagioni A, Amador LG, Frain B, Tu W, Qadadri B, Brown DR. Human papillomavirus infection and its association with cervical dysplasia in Ecuadorian women attending a private cancer screening clinic. Braz J Med Biol Res 2010; 42:629-36. [PMID: 19578642 DOI: 10.1590/s0100-879x2009000700007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Accepted: 05/04/2009] [Indexed: 11/22/2022] Open
Abstract
Women living in Latin American countries bear a disproportionate burden of cervical cancer, a condition caused by infection with the human papillomavirus (HPV). We performed a study in Santa Elena, Guayas (currently Santa Elena Province), Ecuador, to determine how often HPV could be detected in women attending a private cancer screening clinic. Participants underwent a Pap test, and vaginal and cervical swabs were performed for HPV testing by the polymerase chain reaction (PCR). Each participant completed a verbally administered survey. The mean age of 302 participants was 37.7 years (range 18 to 78 years). The majority of cervical and vaginal specimens contained sufficient DNA to perform PCR. Overall, 24.2% of the participants had either a cervical or vaginal swab that tested positive for HPV. In general, there was a good correlation between the HPV types detected in the cervical and vaginal swabs from the participants, but vaginal swabs were more likely to contain HPV DNA than were cervical swabs. The high-risk HPV types 16, 52, 58, and 59 and the low-risk HPV types 62, 71, 72, and 83 were the most frequently detected HPV types. The number of lifetime sexual partners was positively associated with detection of any HPV type, detection of oncogenic HPV, and abnormal Pap smears. Further studies are needed to determine if these results are representative of all Ecuadorian women and to determine if cervical cancers in Ecuadorian women are caused by the same HPV types found in the swab specimens obtained in this study.
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Murray MD, Tu W, Wu J, Morrow D, Smith F, Brater DC. Factors associated with exacerbation of heart failure include treatment adherence and health literacy skills. Clin Pharmacol Ther 2009; 85:651-8. [PMID: 19262464 DOI: 10.1038/clpt.2009.7] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We determined the factors associated with exacerbation of heart failure, using a cohort (n = 192) nested within a randomized trial at a university-affiliated ambulatory practice. Factors associated with emergency or hospital care included left ventricular ejection fraction, hematocrit and serum sodium levels, refill adherence, and the ability to read a prescription label. Refill adherence of <40% was associated with a threefold higher incidence of hospitalization for heart failure than a refill adherence of >or=80% (P = 0.002). In multivariable analysis, prescription label reading skills were associated with a lower incidence of heart failure-specific emergency care (incidence rate ratio, 0.76; 95% confidence interval (CI), 0.19-0.69), and participants with adequate health literacy had a lower risk of hospitalization for heart failure (incidence rate ratio, 0.34; 95% CI, 0.15-0.76). We conclude that inadequate treatment adherence and health literacy skills are key factors in the exacerbation of heart failure. These findings emphasize the need for careful instruction of patients about their medications.
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Theobald DE, Kroenke K, Bhatia S, Walling R, Venkatesh H, Dugan WM, Tu W, Wu J. Cancer patients report high levels of health-related psychosocial distress. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.20533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Wang Y, Tu W, Tang D. RETRACTED: A novel technology of AsS dissolving by immobilized Acidithiobacillus ferrooxidans in double stage chemobiological reactor. Process Biochem 2007. [DOI: 10.1016/j.procbio.2007.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Rosenthal SL, Zimet GD, Leichliter JS, Stanberry LR, Fife KH, Tu W, Bernstein DI. The psychosocial impact of serological diagnosis of asymptomatic herpes simplex virus type 2 infection. Sex Transm Infect 2006; 82:154-7; discussion 157-8. [PMID: 16581745 PMCID: PMC2564691 DOI: 10.1136/sti.2005.016311] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVES To evaluate the impact of a positive herpes simplex virus type 2 (HSV-2) serological test on psychosocial functioning among people with no known history of genital herpes. METHODS Individuals (age 14-30 years) without a history of genital herpes were recruited from an urban university setting and sexually transmitted diseases (STD), primary care, and adolescent clinics. Participants completed a questionnaire addressing psychological functioning, psychosocial adjustment, and perceived quality of sex and were offered free HSV-2 antibody testing. 33 HSV-2 positive people and 60 HSV-2 negative people demographically matched from the same source of recruitment were re-evaluated at a 3 month follow up visit. HSV-2 positive participants also completed a genital herpes quality of life (GHQOL) measure. RESULTS Of the 33 who were HSV-2 seropositive, four did not recall their diagnosis. In comparing those who were HSV-2 positive with those who were negative, repeated measures analysis of variance indicated there were no significant differences over time on any of the measures. None the less, many HSV-2 positive individuals indicated that the diagnosis had a notable impact on their quality of life. Also, among the HSV-2 positive people, lower GHQOL at the 3 month follow up was predicted by higher interpersonal sensitivity (r = -0.44, p<0.05), lower social support (r = 0.40, p<0.05), and quality of sex (r = 0.62, p<0.01) at baseline. CONCLUSIONS A diagnosis of asymptomatic HSV-2 infection does not appear to cause significant lasting psychological difficulties. Those for whom the diagnosis had the greatest impact were interpersonally vulnerable before the diagnosis. These results suggest that assessment of interpersonal distress may be important to include as part of pretest and post-test counselling.
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Khan A, Fortenberry JD, Temkit MH, Tu W, Orr DP, Batteiger BE. Gender differences in sexual behaviours in response to genitourinary symptoms. Sex Transm Infect 2005; 81:262-6. [PMID: 15923299 PMCID: PMC1744983 DOI: 10.1136/sti.2004.010587] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE To understand gender differences in sexual behaviours in response to genitourinary symptoms. METHODS 473 (239 female and 234 male) subjects were enrolled at an STD clinic regardless of symptoms or infection status. Subjects completed a 30 day calendar recall interview of genitourinary symptoms, coital activity, sexual partners, and condom use. RESULTS Of the total of 473 participants, 261 (55%) reported symptoms (61% women and 39% men). STI prevalence was 73% and 75% for symptomatic women and men, respectively. For black women the probability of coitus was decreased in the presence of vaginal discharge (OR 0.64, 95% CI 0.47 to 0.89). No change in coital activity was seen in non-black women in the presence of vaginal discharge. Having vaginal discharge did increase the likelihood of condom use by their partners (OR 2.48, 95% CI 1.05 to 5.88), if coitus occurred. Urethral discharge was not associated with coitus or condom use in men. However, in men, dysuria was associated with increased likelihood of condom use (OR 4.25, 95% CI 1.57 to 11.56) if coitus occurred. CONCLUSION Black women altered both coital activity and condom use behaviours in response to vaginal discharge. In contrast, non-black women did not modify coital activity. Men increased condom use when having dysuria but did not alter coital activity. Changes in sexual behaviours may alter the risk of STI transmission independent of interactions with the healthcare system. STI education and prevention programmes need to better understand these gender and racial differences in developing effective strategies to reduce STI transmission.
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Maclean CH, Newberry SJ, Mojica WA, Issa A, Khanna P, Lim YW, Morton SC, Suttorp M, Tu W, Hilton LG, Garland RH, Traina SB, Shekelle PG. Effects of omega-3 fatty acids on cancer. EVIDENCE REPORT/TECHNOLOGY ASSESSMENT (SUMMARY) 2005:1-4. [PMID: 15777113 PMCID: PMC4781487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
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Shekelle PG, Morton SC, Maglione M, Suttorp M, Tu W, Li Z, Maggard M, Mojica WA, Shugarman L, Solomon V. Pharmacological and surgical treatment of obesity. EVIDENCE REPORT/TECHNOLOGY ASSESSMENT (SUMMARY) 2004:1-6. [PMID: 15526396 PMCID: PMC4781112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
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MacLean CH, Mojica WA, Morton SC, Pencharz J, Hasenfeld Garland R, Tu W, Newberry SJ, Jungvig LK, Grossman J, Khanna P, Rhodes S, Shekelle P. Effects of omega-3 fatty acids on lipids and glycemic control in type II diabetes and the metabolic syndrome and on inflammatory bowel disease, rheumatoid arthritis, renal disease, systemic lupus erythematosus, and osteoporosis. EVIDENCE REPORT/TECHNOLOGY ASSESSMENT (SUMMARY) 2004:1-4. [PMID: 15133890 PMCID: PMC4780987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
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Subramanian U, Weiner M, Gradus-Pizlo I, Wu J, Tu W, Murray MD. 60 PATIENTS' PERCEPTIONS AND PROVIDERS' ASSESSMENTS OF SEVERITY OF HEART FAILURE AS PREDICTORS OF HOSPITALIZATION. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl2-60] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Tu W. Use of electronic adherence with PK parameters to predict outcomes of older adult heart failure patients. Clin Pharmacol Ther 2004. [DOI: 10.1016/j.clpt.2003.11.289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Shekelle P, Hardy ML, Coulter I, Udani J, Spar M, Oda K, Jungvig LK, Tu W, Suttorp MJ, Valentine D, Ramirez L, Shanman R, Newberry SJ. Effect of the supplemental use of antioxidants vitamin C, vitamin E, and coenzyme Q10 for the prevention and treatment of cancer. EVIDENCE REPORT/TECHNOLOGY ASSESSMENT (SUMMARY) 2003:1-3. [PMID: 15523748 PMCID: PMC4781200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
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Shekelle P, Morton S, Atkinson S, Suttorp M, Tu W, Heidenreich P, Gubens M, Maglione M, Jungvig L, Roth E, Newberry S. Pharmacologic management of heart failure and left ventricular systolic dysfunction: effect in female, black, and diabetic patients, and cost-effectiveness. EVIDENCE REPORT/TECHNOLOGY ASSESSMENT (SUMMARY) 2003:1-6. [PMID: 14571595 PMCID: PMC4781559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
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Smilowitz HM, Coderre JA, Nawrocky MM, Tu W, Pinkerton A, Jahng GH, Gebbers N, Slatkin DN. The combination of X-ray-mediated radiosurgery and gene-mediated immunoprophylaxis for advanced intracerebral gliosarcomas in rats. J Neurooncol 2002; 57:9-18. [PMID: 12125969 DOI: 10.1023/a:1015709406449] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Rats with advanced, imminently lethal, approximately 4 mm diameter, left-sided intracerebral 9L gliosarcoma (9LGS), a well characterized malignant tumor with some similarities to human high-grade astrocytomas, were used as a therapy model 14 days post-implantation of 10(4) cells. Such tumor-bearing rats die within two weeks (median, 6 days) thereafter if untreated. However, if these tumors are exposed on day 14 to 12-25 Gy of an electron-equilibrated 6 MV photon beam (radiosurgery), survival is extended about 5-6 fold to a median of 34 days, but long-term survival (> 1 year) is increased only to approximately 18%. Multiple subcutaneous inoculations of radiation-disabled 9LGS cells post-radiosurgery (immunoprophylaxis) extended lifespan and long-term (> 1 year) survival minimally (median, 37 days; 25%, respectively). In sharp contrast, radiosurgery followed by multiple subcutaneous inoculations of radiation-disabled 9LGS cells that had been transfected with granulocyte macrophage colony stimulating factor (GMCSF), a cytokine with demonstrated immune-enhancing properties (i.e. gene-mediated immunoprophylaxis, GMIMPR) increased long-term survival to approximately 67%. To our knowledge, these results are the first to show that the combination of photon radiosurgery and GMIMPR is effective for an advanced, imminently lethal brain tumor in a mammal. These data raise the possibility that GMIMPR following radiation therapy might prove effective for the treatment of some human malignant gliomas.
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Katz BP, Fortenberry JD, Tu W, Harezlak J, Orr DP. Sexual behavior among adolescent women at high risk for sexually transmitted infections. Sex Transm Dis 2002; 28:247-51. [PMID: 11354261 DOI: 10.1097/00007435-200105000-00001] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The temporal pattern of partners and sexual encounters may be key factors in the acquisition and transmission of sexually transmitted diseases (STDs). Behavior among adolescent women is of particular interest because they frequently have the highest prevalence and incidence of infection. GOAL To examine coital diary data collected during a 7-month longitudinal study of young women at high risk of STDs and to describe their sexual behaviors, with particular attention to issues of partner sequence and overlap. STUDY DESIGN A 7-month longitudinal study of young women infected with or having a sexual contact infected with Neisseria gonorrhoeae, Chlamydia trachomatis, or Trichomonas vaginalis attending the STD clinic or one of four neighborhood adolescent health clinics. Data were collected at enrollment and at 1, 3, 5, and 7-month follow-up visits. Coital diaries were kept between visits. RESULTS The average frequency of coital events was 0.94 per week. The median number of sexual partners during the follow-up period was one, and overlapping of partnerships was an uncommon occurrence. The number of days between the last coital event of a current relationship and the first encounter of a new relationship differed for those choosing a new partner (mean, 20.6 days) and those who returned to a previous partner (mean, 7.9 days; P < 0.001). CONCLUSION Although at high risk for STDs, high-risk behavior was not common among the study population. Partner choice and the behavior of these partners may be more important elements than personal high-risk behavior in accounting for the high prevalence of sexually transmitted infections among inner-city adolescent women.
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Tu W, Chen J, Xiao G. [Effects of quinacrine on gut-origin bacteria/endotoxin translocation in rats with gut ischemia/reperfusion injury]. ZHONGHUA SHAO SHANG ZA ZHI = ZHONGHUA SHAOSHANG ZAZHI = CHINESE JOURNAL OF BURNS 2001; 17:301-3. [PMID: 11774821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To explore the influence of quinacrine, which is an inhibitor of phospholipase A2, on gut-origin bacteria/endotoxin translocation in rats with gut ischemia/reperfusion injury. METHODS Forty-two Wistar rats were randomly divided into normal control (C, n = 6), gut ischemia/reperfusion injury control (IC, n = 12), quinacrine use at 3 hours after the injury(3 h, n = 12), and quinacrine use at 12 hours after the injury (12 h, n = 12) groups. The contents of blood endotoxin and TNF alpha in venae cavae and portal vein were measured in all groups. At the same time, tissue samples from mesenteric lymph nodes, liver, lungs and kidneys were harvested for bacterial culture. RESULTS Plasma contents of endotoxin and TNF alpha were lowered in both quinacrine treatment groups (P < 0.01). The incidence of bacterial/endotoxin translocation was decreased by quinacrine use in mesenteric lymph nodes, lungs, liver and kidneys after the injury (P < 0.05 approximately 0.01). CONCLUSION Early application of quinacrine in Wistar rats inflicted by gut ischemia reperfusion injury could obviously lower bacterial/endotoxin translocation and ameliorate the release of pro-inflammatory mediators and cytokines, thus attenuating injury to remote organs.
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Liu E, Tu W, Law HK, Lau YL. Changes of CD14 and CD1a expression in response to IL-4 and granulocyte-macrophage colony-stimulating factor are different in cord blood and adult blood monocytes. Pediatr Res 2001; 50:184-9. [PMID: 11477201 DOI: 10.1203/00006450-200108000-00004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Neonates are relatively immature in their immune response; thus, to further clarify the differences of monocyte function and differentiation between neonates and adults, we investigated their CD14(+)CD4(+) and CD14(+)CD16(+) monocyte subpopulations, production of IL-1beta and tumor necrosis factor-alpha induced by lipopolysaccharide, and their CD14 and CD1a phenotypic changes in response to IL-4 and granulocyte-macrophage colony-stimulating factor. Our results showed that 1) the expression of CD14 in cord blood monocytes was significantly lower than that in adult peripheral blood monocytes; 2) both the percentages of CD14(+)CD4(+) cells and CD14(+)CD16(+) cells among CD14(+) monocytes were also significantly lower in cord blood; 3) after stimulation by lipopolysaccharide for 72 h, production of both IL-1beta and tumor necrosis factor-alpha was lower in cord blood than that in adult peripheral blood; and 4) in response to IL-4 or GM-CSF, the phenotype development of CD14 and CD1a in cord blood and adult peripheral blood was different. Down-regulation of CD14 expression in response to IL-4 and GM-CSF was slower in cord blood monocytes than that in adult peripheral blood monocytes. After 9 d of culture in the presence of IL-4 and GM-CSF, the percentage of CD1a(+) monocytes was significantly more increased in cord blood than that in adult peripheral blood. The reduced expression of CD14 and other mature phenotype markers such as CD16 and CD4 as well as the reduced IL-1beta and tumor necrosis factor-alpha production may contribute to the impaired immune response of neonates. Slower down-regulation of CD14 by IL-4 and GM-CSF suggests that differential properties of cord blood monocytes in response to cellular stress signals take a longer time than those of adult peripheral blood monocytes.
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Tan Z, Tu W, Schreiber SS. Downregulation of free ubiquitin: a novel mechanism of p53 stabilization and neuronal cell death. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2001; 91:179-88. [PMID: 11457508 DOI: 10.1016/s0169-328x(01)00117-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Neuronal death through activation of the p53 stress response pathway has been implicated in the pathogenesis of neurodegenerative disorders. The mechanisms regulating p53 accumulation and function in neurons are poorly understood. Recent evidence has demonstrated that Mdm2 is a major inhibitor of p53 that binds to and targets p53 for ubiquitin-mediated degradation. Here we demonstrate increased expression and co-localization of p53 and Mdm2 in the nuclei of degenerating neurons following treatment with either the excitotoxin, kainic acid, or the topoisomerase I inhibitor, camptothecin. Co-immunoprecipitation studies showed that p53-Mdm2 complexes were present in neuronal lysates. Dual immunofluorescence microscopy demonstrated that these complexes accumulated in neurons with a striking decrease in free ubiquitin levels. Exogenous ubiquitin restored p53 degradation to extracts from injured neurons confirming that Mdm2 function was intact. Finally, antisense-mediated downregulation of ubiquitin in cultured hippocampal neurons resulted in p53 and Mdm2 accumulation as well as apoptotic death. These results point to a novel mechanism to stabilize p53 and promote neuronal cell death in the central nervous system.
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Kaibori M, Inoue T, Tu W, Oda M, Kwon AH, Kamiyama Y, Okumura T. FK506, but not cyclosporin A, prevents mitochondrial dysfunction during hypoxia in rat hepatocytes. Life Sci 2001; 69:17-26. [PMID: 11411802 DOI: 10.1016/s0024-3205(01)01098-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hepatic ischemia/reperfusion injury occurs in the clinical situations including liver transplantation. FK506 and cyclosporin A (CsA) are reported to be hepatotrophic agents in addition to being a powerful immunosuppressive agent. Studies were performed to determine whether the drugs influence a mitochondrial dysfunction under the hypoxic conditions in primary culture model of rat hepatocytes. The Anaeropack system was used for cell culture to create a hypoxia. Cells were treated with FK506 or CsA under the normoxic and hypoxic conditions. Hypoxia markedly decreased intracellular adenosine 5'-triphosphate (ATP) contents and the ketone body ratio (KBR, acetoacetate/beta-hydroxybutyrate) in culture medium as compared with normoxia. FK506 prevented the decreases of ATP contents and the KBR. In contrast, CsA had no effect on either ATP contents or the KBR. FK506, but not CsA, increased the KBR under the normoxic conditions. Under the hypoxic conditions, heat shock protein 70 (Hsp70) was detected after reoxygenation. FK506 enhanced the induction of Hsp70, but CsA again had no effect on Hsp70 induction. These results indicate that FK506 protects the hypoxia injury in part by preventing the mitochondrial dysfunction in concert with the enhancement of heat shock response in hepatocytes.
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Liu E, Tu W, Law HK, Lau YL. Decreased yield, phenotypic expression and function of immature monocyte-derived dendritic cells in cord blood. Br J Haematol 2001; 113:240-6. [PMID: 11328307 DOI: 10.1046/j.1365-2141.2001.02720.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Dendritic cells are critical for the induction of both primary immune responses and immunological tolerance, as well as for the regulation of T-helper 1 (Th1) and 2 (Th2) immune responses. As neonates are notably deficient in Th1 response and cord blood transplantation is noted to result in less graft-versus-host disease (GvHD), we compared the phenotypic and functional characteristics of monocyte-derived dendritic cells (DCs) that favour Th1 development from cord blood and adult peripheral blood to understand the underlying mechanisms of these observations. Our results showed that: (1) after culture for 7 d with interleukin (IL)-4 and granulocyte--macrophage colony-stimulating factor (GM-CSF), cord blood monocytes generated less CD1a(+) cells than adult peripheral blood monocytes, and the CD1a+ cell percentage decreased thereafter; (2) compared with adult blood DCs, cord blood DCs had reduced intensity of expression of CD1a and MHC class II molecules, but the expression levels of CD11c and CD86 were similar; (3) the endocytotic ability of cord blood DCs was reduced compared with adult blood DCs, and this function was related to reduced mannose receptor (MR)-positive cells; (4) furthermore, the ability of cord blood DCs to stimulate CD3(+) T cells in an allogeneic mixed lymphocyte reaction was significantly lower than that of adult blood DCs. These results suggested that the dysfunction of cord blood monocytes in differentiating into professional DCs will affect the activation of naive T cells, especially Th1 development, and may be related to the susceptibility to different infections in the neonates, as well as the lower incidence of GvHD in cord blood transplantation.
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Smilowitz HM, Joel DD, Slatkin DN, Micca PL, Nawrocky MM, Youngs K, Tu W, Coderre JA. Long-term immunological memory in the resistance of rats to transplanted intracerebral 9L gliosarcoma (9LGS) following subcutaneous immunization with 9LGS cells. J Neurooncol 2001; 46:193-203. [PMID: 10902851 DOI: 10.1023/a:1006488301412] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Glioblastoma multiforme (GBM) is the most common primary human brain tumor. About 7000 new cases are diagnosed yearly in the USA. Despite current neurosurgical and postoperative radiotherapeutic tumor cytoreduction methods, in most cases occult foci of tumor cells infiltrate surrounding edematous brain tissues and cause recurrent disease within one year. GBM is almost invariably fatal within a few years after it is diagnosed. Our goal is to achieve long-term control of GBM by combining immunoprophylaxis with a radiation-based technique, such as boron neutron-capture therapy (BNCT), potentially capable of specifically targeting the infiltrating tumor cells while sparing the surrounding normal brain tissue. It has long been known that the subcutaneous (sc) injection of irradiated cells or untreated cultured cells (and the removal of the resulting tumors) derived from the well characterized, highly immunogenic 9L gliosarcoma (9LGS) rat model into young isogenic rats can prevent tumor growth after subsequent sc or intracranial (ic) injection of untreated, otherwise lethal 9LGS cells. In this study we have confirmed, quantified and extended those findings to study the efficacy of such immunological memory in normal aging rats and in aging rats previously treated for ic 9LGS tumors by BNCT. (1) The sc injection of 5,000,000 untreated 9LGS cells and the surgical removal of the resulting tumors (method A) protected 80% of normal young rats from an ic challenge with 10,000 untreated 9LGS cells, and a single sc injection of 5,000,000 lethally X-irradiated 9LGS cells (method B) protected 66% of them, but multiple sc injections with a crude particulate fraction prepared from 9LGS cells were not protective. Protection is long-lasting since contralateral ic rechallenge of six-month survivors with an injection of 10,000 viable 9LGS cells resulted in 100% survival. (2) Normal one-year-old rats were only slightly less protected than were normal young rats, approximately 70% rather than approximately 80% (method A) and approximately 60% rather than approximately 66% (method B). (3) BNCT treatment alone resulted in partial immunological protection, as 30% of one-year post-BNCT survivors of ic 9LGS tumors prevailed after contralateral ic rechallenge with 10,000 viable 9LGS cells. Moreover a single sc immunization with 5,000,000 untreated 9LGS cells prior to ic rechallenge boosted survival from 30% to 100%. The relevance of these observations to strategies of preclinical experimentation for immunoprophylaxis of malignant gliomas is discussed.
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