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71.
BCL-2 protein is a oncoprotein considered to have an important role in the regulation of programmed cell death--apoptosis. The intracellular localization, the relation with other oncoproteins, the antioxidant function and the pathological implications are discussed. 相似文献
72.
Andrea Bonetti Marta Zaninelli Stefania Rodella Annamaria Molino Loris Sperotto Quirino Piubello Franco Bonetti Rolando Nortilli Monica Turazza Gian Luigi Cetto 《Breast cancer research and treatment》1996,38(3):289-297
Summary The relationship between tumor proliferative activity and response to first-line chemotherapy and survival was investigated in 76 advanced breast cancer patients. Proliferative activity was determined by means of Ki-67 immunohistologic staining on primary tumors (55 patients) or at the relapse site (21 patients), and was classified as low ( 25% of stained cells) or high (> 25% of stained cells). The usual WHO response criteria were used. The median duration of follow-up was 18 months (range 3–58).Forty-seven patients (62%) had tumors with low, and 29 (38%) had tumors with a high rate of proliferative activity. The two groups were well balanced in terms of important variables such as disease-free survival, performance status, age, menopausal status, and the type of first-line chemotherapy (anthracycline-based regimens versus cyclophosphamide-methotrexate-5-fluorouracil). The estrogen receptor (ER) content, measured by means of immunohistochemical assay, was markedly different in the two groups, with 27/47 tumors with low proliferative activity (57%) and 6/29 with high-proliferative activity (21%) being ER positive ( 45% of stained cells) (p = 0.003). Moreover, a significant difference in the metastatic pattern was also evident, with a higher incidence of bone and a lower incidence of soft tissue metastases in the group of patients with tumors with low proliferative activity (p = 0.004). Overall, 10/47 responses (21%: PR = 7, and CR = 3) were observed in the group with a low rate of proliferative activity, versus 14/29 (48%: PR = 9, and CR = 5) in the group with highly proliferative tumors, the difference being statistically significant (p = 0.03). When a multivariate analy-sis was performed, the only factor that retained independent prognostic significance was the predominant site of disease, particularly soft tissues (p = 0.003). Despite the difference in response rate, when survival analysis was performed according to the Kaplan-Meier method, no significant difference was observed in the two groups, but when the analysis was limited to responsive patients, the median survival observed in those with a low and those with a high rate of proliferation was 35 and 19 months respectively (p = 0.02). The same results were obtained when multivariate survival analysis was carried out using Cox's regression model. These data suggest that there is a link between tumor proliferative activity and response to chemotherapy in advanced breast cancer, and may indicate the need to use more intensive treatments in selected patients with highly proliferative tumors.Presented in part at the Annual Meeting of the American Society of Clinical Oncology, May 14–17, 1994, Dallas, TX, USA 相似文献
73.
Root bark of West African tree DIOSPYROS BATOCANA H IERN, Ebenaceae, was examined. On the basis of chromatographic and spectral analysis it was shown to contain the naphtaquinones 7-methyljuglone, 2-methylnaphthazarin, biramentaceone, rotundiquinone, mamegakinone, diospyrin, diosquinone, isodiospyrin and batocanone. This last compound proved to be the (-)-enantiomer of isodiospyrin-2', 3'-epoxide. The probable existence of beta-dihydrodiospyrin, of a batocanone isomer and of an isodiospyrin diepoxide in this material is mentioned. The partial synthesis of two isomeric isodiospyrin di-epoxides is described. 相似文献
74.
75.
Ferri-De-Barros JE Veiga JC Priante AV Cardoso CA Alves FL Ferri-De-Barros M Turrini RM Oliveira SD Fontana Junior S 《Arquivos de neuro-psiquiatria》2000,58(1):128-135
INTRODUCTION: Knowledge accumulation is overfilling the thematic content of medical graduation. Medical Schools must be alert to define a minimal content related with the most frequent disturbs. We intent to suggest topics for the minimal content, to the program of Neurology in medical graduation. METHOD: 1. To identify the places where young doctors are working outside the School Hospital (SH): we analysed the answers of the letters sent to 6415 resident - doctors (RD) in S?o Paulo's State and we made personal interview with 201 RD. 2. To verify the most frequent neuropsychiatric disturbs (ND) in the population: we made the analysis of the patient's diagnostic records in emergency room of three institutions: Municipal of Taubaté-SP, Municipal of S?o José dos Campos-SP and Faculty of Medicine of S?o Paulo Santa Casa de Misericórdia. RESULTS: 1. The RD are young and, outside the SH, they work in other emergency services. 2. The most frequent diagnosis in institutions were listed: alcoholism, cerebrovascular disease, coma, cranial trauma, dementia, dizziness, epilepsy, facial paralysis, faint, headache, hemiplegia or paraplegia, meningitis, others paralysis, periferical neuropathy and psychiatric disorders. CONCLUSIONS: Those diagnostics most frequent are relevant topics of the programmatic content to the program of Neurology in medical graduation. 相似文献
76.
Sialyl-Tn antigen (STn) is a mucin-type carbohydrate normally present in goblet cells of small and large bowel. STn expression has been demonstrated to occur in complete and incomplete intestinal metaplasia as well as in many carcinomas but in no normal gastric cell. The aim of our present study was to evaluate the distribution of STn in Helicobacter pylori chronic gastritis (HpCG) of pediatric patients. Eighteen gastric biopsies from 15 children (mean age: 11.5 years) with HpCG, 9 gastric biopsies from 9 children without H. pylori infection, and 1 heterotopic gastric mucosa in Meckel's diverticulum were immunostained using the anti-STn antibody STn1 (18/18), NCL-MUC-1 (7/18), and NCL-MUC-2 (18/18) antibodies. Also, sulfated mucosubstances were investigated with the Alcian Blue-Periodic Acid Schiff (AB-PAS), pH 1.0 stain. Although with different intensity (weak in 5/18, moderate 9/18, and intense 4/18) all cases with HpCG exhibited STn immunoreactivity. The expression of STn was found to be located mainly to the supranuclear region of the epithelial cells at the foveolae and glandular necks, with occasional cells showing diffuse cytoplasmic staining. When reactivity was intense, it was for the most part found in the cells at the neck of the glands. The mucus out of the luminal border above the positive cells was usually also stained. MUC-1 was negative (2/7) or weakly positive (5/7) in a few surface mucous cells. MUC-2 was negative (16/18) or occasionally detected in some foveolar and surface cells (2/18). AB-PAS pH 1.0 revealed the presence of sulfomucins in the cytoplasm of isolated cells of gastric pits and glands of most cases (11/15). None of these findings was observed in the control group. We conclude that STn can be identified in gastric cells of pediatric patients with HpCG and that this does not correlate with other mucosubtances markers. Thefindings could indicate that minimal intestinal metaplasia takes place in children with HpCG. 相似文献
77.
Fernanda B Nunes Cássio M Graziottin José Carlos F Alves Filho Adroaldo Lunardelli Melissa G S Pires Paulo H W?chter Jarbas R De Oliveira 《Pharmacological research》2003,47(1):35-41
Tissue lesion mechanisms provoked by sepsis include the infectious process, inflammation, and cellular energy deficit. We chose to test fructose-1,6-bisphosphate (FBP) because of its possible anti-inflammatory and antimicrobial actions. Wistar rats were used and divided into three experimental groups: a control group (n=10), in which a capsule was introduced into the peritoneum of the animals; a septic group (n=10), in which a capsule containing non-sterile fecal matter was introduced together with Escherichia coli (1.5 x 10(9)CFU); and a septic group treated with FBP 500 mg/kg (n=10). The blood cell tests revealed that levels of leukocytes increased significantly in the septic group when compared to both the septic group treated with FBP and the control group. The blood cultures were 100% positive in both the septic group and the septic group treated with bisphosphorylated sugar. The antibiogram only revealed an inhibitory halo in the case of the antibiotic ampicillin, there was no such indication for FBP. The anti-inflammatory power of FBP remained at 60% for 5 h in the rats that received the carrageenan injection. What is more, the sugar reduced the levels of ionic calcium in relation to the control group. This data proves the validity of using FBP in the treatment of sepsis, possibly due to its anti-inflammatory rather than antimicrobial action. 相似文献
78.
Marta Ruiz Hiroya Kobayashi Juan José Lasarte Jesús Prieto Francisco Borrás-Cuesta Esteban Celis Pablo Sarobe 《Clinical cancer research》2004,10(8):2860-2867
PURPOSE: The purpose of this research was to identify promiscuous T-helper cell determinants (THd) from carcinoembryonic antigen (CEA) to be used to prime T-cell help for cancer therapy. CEA was selected because this antigen is expressed in an important variety of carcinomas. EXPERIMENTAL DESIGN: Potential promiscuous THd from CEA were predicted using available computer algorithms. Predicted peptides were synthesized and tested in binding experiments to different HLA-DR molecules. Binder peptides were then used to prime T-cell responses both in vitro and in vivo. RESULTS: Twenty 15-mer peptides from CEA were predicted to bind to different HLA-DR molecules. The promiscuous character of these peptides was demonstrated in binding experiments. Fifteen of 20 peptides tested were able to bind to HLA-DR4, but only CEA (625-639) was shown to be presented after processing of recombinant CEA. CEA (625-639) was also found to be presented by HLA-DR53. Moreover, immunization of HLA-DR4 transgenic mice with CEA (625-639) in conjunction with class I epitope OVA (257-264), induced a CTL response specific of OVA (257-264). CONCLUSIONS: CEA (625-639) might be a relevant promiscuous THd peptide for cancer therapy. 相似文献
79.
Tania Crombet Marta Osorio Teresa Cruz Carlos Roca Ramón del Castillo Rosa Mon Normando Iznaga-Escobar René Figueredo James Koropatnick Enrique Renginfo Eduardo Fernández Daniel Alvárez Olga Torres Mayra Ramos Idrissa Leonard Rolando Pérez Agustín Lage 《Journal of clinical oncology》2004,22(9):1646-1654
PURPOSE: To evaluate safety and preliminary efficacy of the humanized anti-epidermal growth factor receptor monoclonal antibody h-R3 in combination with radiotherapy (RT) in unresectable head and neck cancer patients. Secondary end points were the measurement of h-R3 serum levels and the assessment of the potential mechanisms of antitumor effect on patient biopsies. Anti-idiotypic response to h-R3 was assessed. To predict pharmacologic effect, a mathematical model for antibodies recognizing antigens expressed in tumors and normal tissues was built. PATIENTS AND METHODS: Twenty-four patients with advanced carcinomas of the head and neck received six once-weekly infusions of h-R3 at four dose levels in combination with RT. Pretreatment tumor biopsies were obtained to evaluate epidermal growth factor receptor expression as an enrollment criterion. Second biopsies were taken to evaluate the proliferative activity and angiogenesis in comparison with the pretreatment samples. Patient serum samples were collected to measure h-R3 levels and anti-idiotypic response. RESULTS: The combination of h-R3 and RT was well tolerated. Antibody-related adverse events consisted in infusion reactions. No skin or allergic toxicity appeared. Overall survival significantly increased after the use of the higher antibody doses. Immunohistochemistry studies of tumor specimens before and after treatment revealed that antitumor response correlated with antiproliferative and antiangiogenic effect. One patient developed antibodies to h-R3. The mathematical model predicted that the maximum difference between the area under the curve in tumors and normal tissues is reached when the antibody has intermediate affinity. CONCLUSION: h-R3 is a well-tolerated drug that may enhance radiocurability of unresectable head and neck neoplasms. 相似文献
80.