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71.
Semaphorin-3F is an inhibitor of tumor angiogenesis 总被引:15,自引:0,他引:15
Kessler O Shraga-Heled N Lange T Gutmann-Raviv N Sabo E Baruch L Machluf M Neufeld G 《Cancer research》2004,64(3):1008-1015
The neuropilin-1 (np1) and neuropilin-2 (np2) receptors form complexes with type-A plexins. These complexes serve as signaling receptors for specific class-3 semaphorins. Np1 and np2 function in addition as receptors for heparin-binding forms of vascular endothelial growth factor (VEGF), such as VEGF(165). Human umbilical vein endothelial cells (HUVEC) express tyrosine-kinase receptors for VEGF and basic fibroblast growth factor (bFGF), as well as np1, np2, and several type-A plexins. We have found that semaphorin-3F (s3f), a semaphorin which signals through the np2 receptor, was able to inhibit VEGF(165), as well as bFGF-induced proliferation of HUVECs. Furthermore, s3f inhibited VEGF as well as bFGF-induced phosphorylation of extracellular signal-regulated kinase-1/2. Our experiments indicate that bFGF does not bind to neuropilins, nor does s3f inhibit the binding of bFGF to FGF receptors. It is therefore possible that s3f inhibits the activity of bFGF by a mechanism that requires active s3f signal transduction rather than by inhibition of bFGF binding to FGF receptors. s3f also inhibited VEGF(165), as well as bFGF-induced in vivo angiogenesis as determined by the alginate micro-encapsulation and Matrigel plug assays. Overexpression of s3f in tumorigenic human HEK293 cells inhibited their tumor-forming ability but not their proliferation in cell culture. The tumors that did develop from s3f-expressing HEK293 cells developed at a much slower rate and had a significantly lower concentration of tumor-associated blood vessels, indicating that s3f is an inhibitor of tumor angiogenesis. 相似文献
72.
Ghadirian P Lubinski J Lynch H Neuhausen SL Weber B Isaacs C Baruch RG Randall S Ainsworth P Friedman E Freidman E Horsman D Tonin P Foulkes WD Tung N Sun P Narod SA 《International journal of cancer. Journal international du cancer》2004,110(3):413-416
The effect of cigarette smoking on the risk of breast cancer is controversial, although most studies show little or no effect. It has been suggested that smoking may reduce the risk of developing hereditary breast cancer. We completed a case-control study on 1,097 women with breast cancer who were BRCA1 or BRCA2 mutation carriers and 1,097 age-matched controls with a mutation in the same gene but without breast cancer. There were no statistically significant differences between the cases and controls in terms of the number of current and ex-smokers (41.2% and 40.4%, respectively) or the age at smoking commencement (18.2 years and 18.5 years, respectively). There were no statistically significant differences between cases and controls regarding beginning smoking within 5 years of menarche (OR = 1.03; 95% CI 0.83 to l.28) or before the first pregnancy (OR = 1.09; 95% CI = 0.90 to 1.33). In conclusion, contrary to our previous report, smoking does not appear to be a risk factor for breast cancer among carriers of BRCA mutations. 相似文献
73.
74.
Kotler M Strous RD Reznik I Shwartz S Weizman A Spivak B 《International clinical psychopharmacology》2004,19(1):23-26
Several recent studies, albeit limited in sample number, design and generalizability, have suggested that augmentation of atypical antipsychotic medication (such as clozapine and olanzapine) with sulpiride, a substituted benzamide antipsychotic medication, may play a role in the management of treatment-resistant psychotic conditions. The objective of this study was to investigate any change in clinical symptomatology or side-effect profile in treatment-resistant schizophrenia patients receiving sulpiride in addition to olanzapine. Seventeen patients with treatment-resistant chronic schizophrenia, who were receiving olanzapine monotherapy for at least 6 months before study commencement, were randomized in a 1:1 fashion to receive either adjunctive treatment with sulpiride (study group) or to continue their pre-study treatment with olanzapine with no medication augmentation (control group), each for a period of 8 weeks. Changes in measures of positive and negative symptoms, anxiety, depression and extrapyramidal symptoms were assessed at baseline and at 8 weeks. Study observations indicated no significant differences in the changes in positive or negative symptomatology between patients receiving a combined regimen of olanzapine with sulpiride (600 mg/ day) augmentation and controls. However, a significantly greater improvement of depressive symptomatology (P < 0.05; as assessed by the Hamilton Scale for Depression) was noted in the sulpiride augmentation group. These data indicate improvement in depressive symptomatology with sulpiride augmentation of olanzapine in treatment-resistant chronic schizophrenia patients. 相似文献
75.
Gal I Gershoni Baruch R Haber D Dagan E Eisenberg-Barzilai S Zidan J Friedman E 《Familial cancer》2004,3(1):11-14
Few mutations have been described in BRCA1 and BRCA2 in high-risk non-Ashkenazi Jews. In a Libyan family the 1100delAT BRCA1 mutation was detected and the 8765delAG BRCA2 mutation was previously described in two Jewish-Yemenite-families. In this study, the rate of these mutations in high-risk Jews of North African and Yemenite origin was assessed, and the BRCA1 -linked haplotype of Jewish and non-Jewish 1100delAT mutation carriers were compared. Genotyping included 64 high-risk Yemenite women (tested only for the BRCA 2 mutation) and 147 high-risk North African women, tested for both mutations. PCR amplification was followed by either restriction enzyme digestion or DGGE or dHPLC analyses and direct sequencing. For haplotyping, 5 BRCA1 -linked markers were used. Neither the 1100delAT BRCA1 nor the 8765delAG BRCA2 mutations were detected in any non-Ashkenazi individual. The haplotype of the non-Jewish 1100delAG mutation carrier differed from that of the Jewish-Libyan mutation carriers. We conclude that both1100delAT BRCA1 and 8765delAG BRCA2 mutations occur rarely in high-risk non-Ashkenazi Jews, and while the latter seems to be a founder mutation in some populations, the former occurs on a different background in ethnically diverse families. 相似文献
76.
77.
Evans MI Wapner RJ Ayoub MA Shalhoub AG Feldman B Yaron Y 《Fetal diagnosis and therapy》2002,17(6):343-346
Multifetal pregnancy reduction (MFPR) has clearly improved the outcomes of multifetal gestations. Several recent reports have also suggested improved outcomes in nonreduced cases, but there have been methodologic concerns about the denominators, i.e. have all cases been included and is there a 'hidden mortality' of unknown lost cases. Here we assessed the outcome of patients telephoning to discuss MFPR, but who chose not to have the procedure. Over a 3-year period, 446 patients had MFPR by one operator. Nineteen patients chose not to have the procedure. There were 11 preterm births, 1 term delivery, and 5 spontaneous losses (7 of 17) prior to 24 weeks, a loss rate of 35%. Two patients delivering triplets had a loss of 1 fetus/neonate. These data suggest that the loss rates of nonreduced pregnancies may be higher than generally thought, making the improvements with MFPR even bigger than generally realized. 相似文献
78.
79.
Two commonly accepted metabolic theories of aging interpret senescence either in terms of the rate of living, where a fixed total metabolic potential is consumed over an expected lifetime (after which the organism wears out and dies) or, in terms of accumulative oxidative damage resulting in progressive and irreversible changes in metabolic pathways. Protocols based on restricted diets, chronically administered anti-oxidants and the use of established lines of organisms resistant to free radical damage support the metabolic theories of aging by revealing, in many cases, significant extensions of life spans or dramatic anti-aging effects. To test the universality of these metabolic hypotheses of aging, we acutely treated ramets (clonal replicates) from old, long-lived colonies of the urochordate Botryllus schlosseri with lethal doses of the anti-oxidant butylated hydroxytoluene (BHT). This group of organisms has a weekly cyclical and highly synchronized developmental process (blastogenesis), during which all existing zooids are removed by massive apoptosis and phagocytosis processes. In animals treated with BHT, blastogenesis was completely arrested and colonies deteriorated to a morphologically chaotic state. Rescued ramets resorbed BHT treated zooids, regenerated entirely new sets of zooids and then revealed: (1) rejuvenescence and enhanced growth rates and in many cases, (2) up to 4.6 times extension of post-treatment life expectancy. Both metabolic theories for senescence were therefore falsified in B. schlosseri. The possible existence of an aging clock that can be set by the environment is suggested. 相似文献
80.
Umbilical granulomas are common inflammatory reactions to the resolving umbilical stump. The double-ligature technique is simple to perform and provides good cosmetic and functional results with only minor complications. The granuloma becomes necrotic and drops off within seven to 14 days. The double-ligature is a preferable alternative to multiple topical applications of silver nitrate for the treatment of pedunculated umbilical granulomas in children. 相似文献