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Mutations of the ras gene family appear to be an uncommon genetic alteration in SCCHN. A common region of DNA amplification on chromosome 11q13 has been identified in SCCHN. A cluster of proto-oncogenes (int-2, hst-1, bcl-1, prad-1) has been localized to the 11q13 region. Studies are needed to determine the critical genes in 11q13 whose expression drive the amplicon. Mutations of the p53 tumor suppressor gene are the most common genetic alteration in SCCHN. The hope is that dysregulated oncogenes or tumor suppressor genes may be targets for specific therapy. 相似文献
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We have undertaken a series of studies to elucidate the roles of growth factors (FGF-2, EGF, TGF-beta1) and prolactin (PRL) in lacrimal gland function during pregnancy and lactation, and to better understand the status of the immune system within the lacrimal gland during those physiological states. In this initial study, lacrimal glands of pregnant (d15, d29), lactating (9d, 22d), and adult female control rabbits, were evaluated by immunohistochemistry, Western blotting and image analysis. In control rabbits EGF, TGF-beta1, and PRL, were immunolocalized primarily in the apical cytoplasm of intralobular ductal epithelial cells, and acini demonstrated a basement membrane-associated immunopositivity for TGF-beta1. FGF-2 immunolocalized in myoepithelial cells in the basal ductal epithelium and complexed to the basement membrane enclosing ducts and acini. Cells immunopositive for immune cell markers (RTLA and CD18) were apparent primarily around interlobular ducts. In d29 pregnant rabbits immunopositivity for EGF and TGF-beta1 was increased within intralobular ducts, both apically and basally, and within some interlobular ductal epithelial cells. Immunopositivity for PRL was strongest in d29 pregnant rabbits within the apical and basal cytoplasm of intralobular ductal epithelial cells. Immunopositivity for FGF-2 in myoepithelial cells was strong in d15 and d29 pregnant rabbits, although basement membrane-associated immunopositivity around acini was often decreased. Immunostaining for EGF and TGF-beta1 in lactating rabbits was similar to that in d29 pregnant rabbits, although basement membrane-associated immunopositivity around acini was more comparable to controls. By 22d lactation immunopositivity for FGF-2 closely resembled that in controls. Image analysis of pregnant and lactating rabbits demonstrated that cells immunopositive for RTLA and CD18 were less abundant around ducts and more abundant between acini, although in 22d lactating rabbits the size of periductal foci was increased to nearly that of controls. Western blots correlated well with the immunohistochemistry. Our findings demonstrate that pregnancy and lactation are accompanied by a shift in the distributions of growth factors and PRL, suggestive of increased release both apically into the lacrimal fluid and basally into the interstitium. Additional shifts in the distributions of cells of the immune system from periductal foci to interacinar sites suggest that there is a recruitment of immune cells away from ducts and toward the connective tissue interstitium surrounding the acini, possibly as part of a heightened state of immune readiness during pregnancy and lactation. 相似文献
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Schechter BA Rand WJ Velazquez GE Williams WD Starasoler L 《American journal of ophthalmology》2002,134(2):268-270
PURPOSE: Two patients with biopsy-proven conjunctival papillomata exhibited complete resolution after treatment with topical Interferon Alfa-2b (IFNalpha2b). DESIGN: Interventional case reports. METHODS: Two patients with monocular biopsy-confirmed conjunctival papillomata were treated with IFNalpha2b, 1 million units/cc, one drop four times daily until clinical resolution was achieved. RESULTS: (Patient 1) The lesion's size was significantly reduced at 1 month. Complete resolution was noted at the 3-month visit. No recurrences were seen 40 months post-treatment. (Patient 2) The lesion completely resolved after 6 weeks of treatment. No recurrence has occurred 18 months post-treatment. No systemic or local side effect of treatment was noted. CONCLUSIONS: Two sizable conjunctival papillomata resolved using topical IFNalpha2b alone. Interferon is usually not considered effective for large solid tumors without surgical debulking. We realize that this is a limited case series, but these cases may serve as a basis for further investigation. 相似文献
75.
Zhu Z Stevenson D Ritter T Schechter JE Mircheff AK Kaslow HR Trousdale MD 《Cornea》2002,21(2):210-214
PURPOSE: To determine whether the expression of either interleukin-10 (IL-10) or tumor necrosis factor (TNF) inhibitor genes in transduced rabbit lacrimal gland epithelial cells suppresses lymphocyte proliferation in an autologous mixed cell reaction, an apparent in vitro model of autoimmune dacryoadenitis. METHODS: Purified lacrimal gland epithelial cells, transduced with an adenovirus vector carrying either viral IL-10 or TNF-inhibitor genes, were used to study their effects on the proliferation of autologous lymphocytes as monitored by 3H-thymidine incorporation in a mixed cell reaction. After transduction, both epithelial cells and lymphocytes were cultured separately for 2 days and then epithelial cells were irradiated. Equal numbers of both cell types were then cocultured together for 5 days. Cocultures were pulsed with 3H-thymidine and isotope incorporation was determined. Gene expression was detected by enzyme-linked immunosorbent assay and Western blots. RESULTS: Lymphocyte proliferation was stimulated by epithelial cells and 3H-thymidine incorporation was significantly greater in these cocultures than in controls. The proliferation was significantly diminished in the presence of transduced cells producing either IL-10 or TNF inhibitor. CONCLUSIONS: Transduction of lacrimal gland epithelial cells with adenovirus vectors encoding for either IL-10 or TNF-inhibitor proteins leads to expression of functional proteins capable of suppressing lymphocyte proliferation. Thus, lacrimal gland epithelial cells are a plausible target for gene therapy methods meant to produce immunoregulatory proteins. 相似文献
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Funding priorities for medical research 总被引:1,自引:0,他引:1
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Sivin I Mishell DR Diaz S Biswas A Alvarez F Darney P Holma P Wan L Brache V Kiriwat O Abdalla K Campodonico I Pasquale S Pavez M Schechter J 《Contraception》2000,61(3):187-194
Soft tubing Norplant(R) contraceptive implants were studied in 1210 women for 7 years to measure the duration of effectiveness and the magnitude of the pregnancy rates over that time. Mean age at enrollment was 27.4 years. Of the enrollees, 42% were US residents. One-sixth (16.1%) weighed >/=70 kg at the time of implant placement. At the end of 5 years, the cumulative pregnancy rate was 1.1/100; at the end of 7 years, it was 1.9/100. No pregnancies occurred to any of the 400 women who enrolled in the study at age >/=30 years and who weighed <100 kg. Among women aged 18-33 years, the 7-year Norplant pregnancy rates are comparable to the median pregnancy rates of tubal sterilization methods for women of the same age and duration of use. For women aged >/=34 years, without regard to weight at admission, the 7-year effectiveness of soft tubing Norplant equals or surpasses that of tubal sterilization. For continuing implant users, annual pregnancy rates <1.0/100 in years 6 and 7, together with low cumulative pregnancy rates, testify that Norplant capsule implants remain highly effective for 7 years. 相似文献