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121.
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Seung-Youp Shin Sung-Jin Choi Gyu-Young Hur Kun-Hee Lee Sung-Wan Kim Joong-Saeng Cho Hae-Sim Park 《Pediatric allergy and immunology》2009,20(2):134-141
Adenoids are known as immunosecretory organs and those in atopic children present cellular and cytokine profiles different from those of non‐atopic children. We hypothesized that locally produced total IgE and allergen‐specific antibodies could be involved in the inflammatory responses in adenoid tissue. Local productions of total IgE and Dermatophagoides pteronyssinus (DP)‐specific IgE, IgA, IgG1, and IgG4 antibodies were evaluated, as well as their relationships with the markers of allergic inflammation within adenoid tissue. Eighteen atopic subjects, who were sensitized to more than one common aeroallergen, and 22 non‐atopic subjects undergoing adenotonsillectomy, were recruited. Immunoassays using adenoid tissue homogenate were performed to quantify the levels of total IgE, eosinophil cationic protein (ECP), and mast cell tryptase. DP‐specific IgE, IgA, IgG1, and IgG4 antibodies, soluble IL‐2 receptors (sIL‐2R), soluble CD23 (sCD23), and IL‐6 were measured by ELISA. All parameters measured in adenoid tissue homogenate were presented as a ratio to the albumin level found in the adenoid. Median level of total IgE in adenoid tissue homogenate was significantly higher in atopic individuals than in non‐atopic individuals. Median values of DP‐specific IgE and IgA antibodies were significantly higher in atopics than in non‐atopics (p = 0.001, p = 0.006, respectively), while no differences were seen in DP‐specific IgG1 and IgG4 antibodies. ECP and sCD23 levels in adenoid homogenate were significantly higher in atopics than in non‐atopics (p = 0.026, p = 0.048, respectively), while no significant differences were noted in tryptase, sIL‐2R, and IL‐6 levels. The levels of DP‐specific IgE, IgA, IgG1, and IgG4 antibodies in adenoid homogenate correlated significantly with ECP levels, but not with those of sIL‐2R, sCD23, and IL‐6. The presence of total IgE and DP‐specific antibodies in adenoid tissue was confirmed to be more prominent in atopics. In conclusion, locally‐produced total IgE and DP‐specific antibodies may contribute to eosinophilic inflammation in adenoid tissue in atopic children. 相似文献
123.
NU Jerath JS Newman & CJ Boes 《Cephalalgia : an international journal of headache》2009,29(10):1028-1033
The aim of this study was to review the life of Mary E. O'Sullivan and to summarize her important contributions to the study of migraine. Mary E. O'Sullivan underwent extensive training to become a neurologist at a time when only 5% of women in America were physicians. She published five papers on migraine. In a 1936 Journal of the American Medical Association article, she described a patient with ergotamine overuse headache and recommended that daily doses of oral ergotamine should be avoided. Three years later she described migraine as a 'complex' syndrome with multiple causes and multiple cures. Mary E. O'Sullivan, an ambitious female headache specialist of the 1930s, was an early advocate of the use of ergotamine to treat migraine, yet she was one of the first to report ergotamine overuse headache. Although her life was short, her research, knowledge and ambition at a time when women had limited opportunities in medicine have left a mark. 相似文献
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AAC-11 overexpression induces invasion and protects cervical cancer cells from apoptosis 总被引:3,自引:0,他引:3
Kim JW Cho HS Kim JH Hur SY Kim TE Lee JM Kim IK Namkoong SE 《Laboratory investigation; a journal of technical methods and pathology》2000,80(4):587-594
To identify the genes involved in cervical carcinogenesis, we applied the mRNA differential display (DD) method to analyze normal cervical tissue, cervical cancer, metastatic lymph node, and cervical cancer cell line. We cloned a 491-bp cDNA fragment, CC231, which was present in metastatic tissue and cervical cancer cell line, but absent in normal cervical and cervical cancer tissues. The 491 bp cDNA fragment has 98% homology to the previously published sequence, AAC-11 (antiapoptosis clone 11). The levels of AAC-11 mRNA expressions in nine normal cervical and nine primary cervical cancer tissues were low. Its expression was higher in three metastatic tissues and five cervical cancer cell lines (HeLa, CaSki, SiHa, CUMC-3, and CUMC-6). Invasion of matrigel and adhesion to laminin by AAC-11 transfected CUMC-6 cells were increased by approximately 2-fold and 4-fold, respectively. Northern blot analysis showed that matrix metalloproteinase (MMP)-2 and membrane type 1 MMP (MT1-MMP) genes were found to be expressed in high levels in AAC-11-transfected cancer cells. But MMP-2 and MT1-MMP were not expressed in cells transfected with vector alone or wild-type cells. AAC-11-transfected cells expressed an elevated level of MMP-2 protein as assessed by immunoblotting. On the contrary, tissue inhibitor of MMP (TIMP-2) expression was detectable in cells transfected with vector alone or wild-type cells, respectively. Its expression was undetectable in AAC-11 transfected cells. In cervical cancer cells transfected with AAC-11, the expression of beta-catenin was up-regulated. These suggest that overexpressions of MMP-2 and MT1-MMP, loss of TIMP-2 expression, and up-regulation of beta-catenin by AAC-11 transfection may contribute to the development of cervical cancer invasion. AAC-11 gene transfection increased cervical cancer cell colonization. The effect of AAC-11 on cultured cervical cancer cells was associated with antiapoptotic process. Approximately 50% of the AAC-11 transfected cells in serum-free medium died after 2 weeks, compared to 1 week for vector alone or wild-type cells. These results suggest that AAC-11 may serve as a candidate metastasis-related and apoptosis-inhibiting gene in human cervical cancer. 相似文献
126.
R Abir I Zusman H Ben Hur P Yaffe A Ornoy 《Acta obstetricia et gynecologica Scandinavica》1990,69(1):27-33
It is generally believed that some human miscarriages result from embryotoxic factors existing in the sera. To study the embryotoxicity of such sera, 3.5-day-old mouse blastocysts were cultured for 72 h on 80% sera from different groups of women. After 72 h there was no blastocystic development in 53.2% of the cases grown on sera from women after two or more miscarriages, and none in 33.6% of the blastocysts grown on sera from women after one miscarriage, as compared with 8.2% and 12% respectively on control sera. Sera from women with miscarriages were divided into 'high risk' (50% or more embryotoxicity) and 'low risk' (less than 50% embryotoxicity) sera. The 'high risk' sera from two or more miscarriages caused an average of 72.1% undevelopment, while the 'low risk' sera (less than 50% embryotoxicity) from the same group caused 33.6% undevelopment. The 'high risk' sera from one miscarriage were embryotoxic to 55.8% of the blastocysts and the 'low risk' sera from the same group caused only 8.7% undevelopment. No significant differences were found in the mean serum concentrations of folic acid, zinc and copper of many of the experimental groups, in comparison with controls. The embryotoxic factor/s which exist in the 'high risk' sera from women with miscarriages are still not known. 相似文献
127.
Comparison of formation of reactive conformers for the SN2 displacements by CH3CO2- in water and by Asp124-CO2- in a haloalkane dehalogenase 总被引:1,自引:0,他引:1 下载免费PDF全文
Hur S Kahn K Bruice TC 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(5):2215-2219
The S(N)2 displacement of Cl(-) from 1,2-dichloroethane by acetate (CH(3)CO(2)(-)) in water and by the carboxylate of the active site aspartate in the haloalkane dehalogenase of Xanthobacter autothropicus have been compared by using molecular dynamics simulations. In aqueous solution, six families of contact-pair structures (I-VI) were identified, and their relative concentrations and dissociation rate constants were determined. The near attack conformers (NACs) required for the S(N)2 displacement reaction are members of the IV (CH(3)COO(-)...CH(2)(Cl)CH(2)Cl) family and are formed in the sequence II-->III-->IV-->NAC. The NAC subclass is defined by the COO(-)...CCl contact distance of < or = 3.41 A and the COO(-)...CCl angle of 157-180 degrees. The mole percentage of NACs is 0.16%, based on the 1 M standard state. This result may be compared with 13.4 mole percentage of NACs in the Michaelis complex in the enzyme. It follows that NAC formation in the enzyme is favored by 2.6 kcal/mol. Because reaction coordinates from S to TS, both in water and in the enzyme, pass via NAC (i.e., S --> NAC --> TS), the reduction in the S --> NAC barrier by 2.6 kcal/mol accounts for approximately 25% of the reduction of total barrier in the S --> TS (10.7 kcal/mol). The remaining 75% of the advantage of the enzymatic reaction revolves around the efficiency of NAC --> TS step. This process, based on previous studies, is discussed briefly. 相似文献
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130.
Corman JM Penson DF Hur K Khuri SF Daley J Henderson W Krieger JN 《BJU international》2000,86(7):782-789
OBJECTIVE: To determine whether radical nephrectomy causes less morbidity, less mortality and is associated with a shorter hospital stay than is partial nephrectomy. PATIENTS AND METHODS: A total of 1885 nephrectomies (1373 radical and 512 partial) conducted between 1991 and 1998 in the Department of Veterans Affairs (VA) National Surgical Quality Improvement Program were evaluated. Using multivariate analyses, outcomes were risk-adjusted based on 45 preoperative variables to compare mortality and morbidity rates. RESULTS: The unadjusted 30-day mortality was 2.0% for radical and 1.6% for partial nephrectomy (P = 0.58). Risk-adjusting the two groups did not result in a statistically significant difference in mortality. The 30-day overall morbidity rate was 15% for radical and 16.2% for partial nephrectomy (P = 0.52); risk-adjusted morbidity rates were not statistically different. There were no statistically significant differences in the rates of postoperative progressive renal failure, acute renal failure, urinary tract infection, prolonged ileus, transfusion requirement, deep wound infection, or extended length of stay. CONCLUSIONS: Partial nephrectomy carried out in the VA program has low morbidity and mortality rates, comparable with the complication rates after radical nephrectomy. 相似文献