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551.
Idelevich E Mozes M Ben-Baruch N Huszar M Kruglikova A Katsnelson R Shani A 《American journal of clinical oncology》2003,26(3):259-261
The objective of this study was to assess the degree of expression and prognostic significance of c-erbB-2, p53, and bcl-2 in male breast cancer (MBC). Thirty male patients with the diagnosis of adenocarcinoma of the breast were studied retrospectively. All patients underwent surgery; c-erbB-2, p53, and bcl-2 were immunohistochemically stained on sections from formalin-fixed, paraffin-embedded tissues. Seventeen (56.7%) of the 30 cases of MBC were bcl-2 positive. Few specimens were found positive for c-erbB-2 (6.7%) and p53 (6.7%). The 5-year survival rate was marginally better for those patients with tumors staining positively for bcl-2 (p = 0.05). It was impossible to estimate the association between survival rate and p53 and c-erbB-2 expression because of the small number of positively stained specimens. In this study, only bcl-2 showed marginal association to other tumor parameters and a trend toward a better 5-year survival rate. At present there is inadequate evidence to support the use of molecular markers as independent prognostic markers in MBC. 相似文献
552.
Dremencov E Newman ME Kinor N Blatman-Jan G Schindler CJ Overstreet DH Yadid G 《Neuropharmacology》2005,48(1):34-42
Dopamine release in the nucleus accumbens mediates motivation and reward, making it a likely candidate to be involved in anhedonia, one of the major symptoms of depression. In the current study, alterations in basal extracellular dopamine levels and 5HT2C receptor-mediated inhibition of accumbal dopamine release in Flinders Sensitive Line (FSL) rats, an animal model of depression, were investigated. We found that FSL rats have decreased extracellular dopamine levels in the nucleus accumbens and an increased inhibitory-like effect of 5HT2C receptors on accumbal dopamine release. However, neither basal 5HT levels nor the accumbal 5HT response to the local 5HT2C receptor antagonist (RS 102221) differed between Sprague-Dawley and FSL rats. Seven-day treatment with the nefazodone (a serotonin/noradrenaline reuptake inhibitor and 5HT2C antagonist) as well as 7-day and 14-day treatments with a tricyclic antidepressant desipramine increased extracellular dopamine levels in the nucleus accumbens of FSL rats. However, only 14-day treatment with desipramine or 7-day treatment with nefazodone, but not 7-day treatment with desipramine, decreased 5HT2C receptor-mediated inhibition of accumbal dopamine release. Based on a possible correlation between the onset of 5HT2C receptor-mediated inhibition and the behavioral effects of desipramine and nefazodone treatment that was described in our previous studies, we suggest that 5HT2C receptor activation may be important for the onset of the behavioral effects of antidepressant treatment. 相似文献
553.
Gámez R Alemán CL Más R Noa M Rodeiro I García H Hernández C Menéndez R Aguilar C 《Journal of medicinal food》2001,4(2):57-65
Policosanol is a cholesterol-lowering drug purified from sugar cane. Previous toxicological studies have not demonstrated any policosanol-related toxicity, even with long-term oral administration at 500 mg/kg, a dose 1,724 times larger than the maximal therapeutic dose (20 mg/day) recommended to date. The present study was undertaken to investigate the oral toxicity of policosanol administered for 6 months in doses up to 5,000 mg/kg to Sprague-Dawley rats. Animals were randomly distributed in five groups (15 animals per dose per sex): a control and four groups given oral policosanol (50, 500, 2,500, or 5,000 mg/kg). Eight treated rats (6 males, 2 females) died during the study, five of them (4 males, 1 female) from among those receiving the highest dose (5,000 mg/kg). According to necropsy, all deaths were related to gavage manipulation of higher doses. Although the differences were not significant, body weight gain and food consumption in the groups receiving 2,500 or 5,000 mg/kg tended to be lower than in the control group. Nevertheless, no drug-related toxicity symptoms were detected. Analysis of blood biochemistry, hematology, organ weight ratios, and histopathological findings did not show significant differences compared with controls, nor any tendency with the dose. Therefore, the present study did not show any new evidence of oral toxicity of policosanol, and the findings observed were a consequence of long-term administration by gastric gavage of the highly concentrated suspensions needed to reach the higher doses. It is concluded that policosanol chronically administered by the oral route is safe and that no drug-related toxicity was demonstrated. 相似文献
554.
Cohen CJ Hoffmann N Farago M Hoogenboom HR Eisenbach L Reiter Y 《Cancer research》2002,62(20):5835-5844
The recent characterization of MHC-displayed tumor-associated antigens that recognize effector cells of the immune system has created new perspectives for cancer therapy. Antibodies that recognize these tumor-associated MHC-peptide complexes with the same specificity as the T-cell antigen receptor will therefore be valuable tools for immunotherapy, as well as for studying antigen presentation in human cancers. Most tumor-associated antigens are expressed in only one or a few tumor types; however, specific T-cell epitopes derived from the Mucin-1 tumor-associated antigen (MUC1) that are widely expressed in many cancers were identified and shown to be recognized by CTLs. We selected a large nonimmune repertoire of phage Fab antibodies on recombinant human class I HLA-A2 complexes displaying an antigenic T-cell epitope derived from MUC1. High frequency of anti-MHC-peptide binders was observed (84%), and surprisingly, a high percentage (80%) of antibodies was fully specific for the MUC1 epitope. We isolated a surprisingly large panel of 16 different high-affinity human recombinant Fab antibodies that exhibited peptide-specific, MHC-restricted binding characteristics of T cells. The analyzed Fabs not only recognize the cognate MHC-peptide complex in a recombinant soluble form but also the native complex as displayed on the surface of antigen-presenting cells and breast tumor cells. Therefore, these findings demonstrate the ability to transform the unique fine specificity but low intrinsic affinity of T-cell receptors on T cells into high-affinity soluble antibody molecules endowed with a T-cell antigen receptor-like specificity. These molecules may prove to be very important and widely applicable for monitoring the expression of specific MHC-peptide complexes on the surface of tumor and immune cells for structure-function studies of T-cell receptor-peptide-MHC interactions, as well as for developing new targeting agents for immunotherapy. 相似文献
555.
D-003 is a mixture of very high molecular weight aliphatic primary acids purified from sugar cane (Saccharum officinarum, L.) wax, in which octacosanoic acid is the most abundant component. Previous experimental studies have shown that D-003 not only shows cholesterol-lowering and antiplatelet effects, but also offers strong protection against plasma lipoprotein oxidation. Acute hepatotoxicity induced by CCL4 in rats has been related to an increased rate of lipid peroxidation, and different antioxidant compounds have been revealed to be effective in this model. The aim of this study was to investigate the effects of D-003 in acute hepatotoxicity induced by CCL4 in rats. Male Sprague Dawley rats were randomly distributed in four experimental groups as follows: group 1: negative control rats; group 2: positive control rats (CCL4-treated); groups 3 and 4 rats with liver damage induced by CCL4 and treated with D-003 at 25 and 100 mg/kg, respectively. Acute liver injury was induced by CCL4 suspended in olive oil and intraperitoneally administered at 1 ml/kg. Eighteen hours after CCL4 dosing, the rats were anesthetized with ether and their livers were removed for histopathological studies. D-003 at 25 and 100 mg/kg significantly (p < 0.01) decreased the percentage of ballooned cells and hepatocytes with lipidic inclusions and increased the percentage of normal hepatocytes compared with that in positive controls in a dose-dependent manner. The percent inhibitions of the occurrence of ballooned cells and hepatocytes with lipids were marked (75% and 50%, respectively) with the high dose (100 mg/kg). The percent of turgent hepatocytes was also significantly reduced compared with that in positive controls, but this effect was not dose-dependent. No histological alterations in the liver sections of negative controls were found. Necrotic areas and inflammatory infiltrate were observed in the liver of 7/8 (87.5%) of positive controls. In turn, D-003 dramatically reduced both necrotic areas and inflammatory infiltrate and was present in only 1/8 (12.5%) animals treated with D-003 25 mg/kg and in none (0%) of the animals treated with 100 mg/kg. D-003 protected against the histological changes characteristic of CCL4-induced hepatic injury in rats, in which the process of lipid peroxidation plays the main role. The relationship between this protective action of D-003 on this experimental model and its antioxidant effects needs to be further investigated before definitive conclusions are drawn. 相似文献
556.
557.
Armarnik Sharon Mimouni Michael Goldenberg Dafna Segev Fani Meshi Amit Segal Ori Geffen Noa 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2019,257(6):1247-1252
Graefe's Archive for Clinical and Experimental Ophthalmology - The purpose of the study was to describe findings demonstrated by anterior segment spectral domain optical coherence tomography... 相似文献
558.
559.
Noa P. Yee Saman Kashani Thomas Mailhot Talib Omer 《The American journal of emergency medicine》2019,37(1):177.e1-177.e4
Optic neuritis (ON) is an inflammatory condition that causes demyelination and thickening of the optic nerve leading to acute/subacute vision loss. It is frequently associated with other conditions like multiple sclerosis, but is often misdiagnosed, which can lead to a suboptimal prognosis.Ultrasound is rarely utilized to help make this diagnosis, even though it can easily detect a thickened retrobulbar optic nerve sheath diameter.We describe four cases in which ultrasonographic measurement of the optic nerve sheath diameter aided in the diagnosis of ON. 相似文献
560.
Joshua Mangerel Aryeh Price Pedro Castelo-Branco Jack Brzezinski Pawel Buczkowicz Patricia Rakopoulos Diana Merino Berivan Baskin Jonathan Wasserman Matthew Mistry Mark Barszczyk Daniel Picard Stephen Mack Marc Remke Hava Starkman Cynthia Elizabeth Cindy Zhang Noa Alon Jodi Lees Irene L. Andrulis Jay S. Wunder Nada Jabado Donna L. Johnston James T. Rutka Peter B. Dirks Eric Bouffet Michael D. Taylor Annie Huang David Malkin Cynthia Hawkins Uri Tabori 《Acta neuropathologica》2014,128(6):853-862
Although telomeres are maintained in most cancers by telomerase activation, a subset of tumors utilize alternative lengthening of telomeres (ALT) to sustain self-renewal capacity. In order to study the prevalence and significance of ALT in childhood brain tumors we screened 517 pediatric brain tumors using the novel C-circle assay. We examined the association of ALT with alterations in genes found to segregate with specific histological phenotypes and with clinical outcome. ALT was detected almost exclusively in malignant tumors (p = 0.001). ALT was highly enriched in primitive neuroectodermal tumors (12 %), choroid plexus carcinomas (23 %) and high-grade gliomas (22 %). Furthermore, in contrast to adult gliomas, pediatric low grade gliomas which progressed to high-grade tumors did not exhibit the ALT phenotype. Somatic but not germline TP53 mutations were highly associated with ALT (p = 1.01 × 10?8). Of the other alterations examined, only ATRX point mutations and reduced expression were associated with the ALT phenotype (p = 0.0005). Interestingly, ALT attenuated the poor outcome conferred by TP53 mutations in specific pediatric brain tumors. Due to very poor prognosis, one year overall survival was quantified in malignant gliomas, while in children with choroid plexus carcinoma, five year overall survival was investigated. For children with TP53 mutant malignant gliomas, one year overall survival was 63 ± 12 and 23 ± 10 % for ALT positive and negative tumors, respectively (p = 0.03), while for children with TP53 mutant choroid plexus carcinomas, 5 years overall survival was 67 ± 19 and 27 ± 13 % for ALT positive and negative tumors, respectively (p = 0.07). These observations suggest that the presence of ALT is limited to a specific group of childhood brain cancers which harbor somatic TP53 mutations and may influence the outcome of these patients. Analysis of ALT may contribute to risk stratification and targeted therapies to improve outcome for these children. 相似文献