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排序方式: 共有6573条查询结果,搜索用时 15 毫秒
31.
Joseane C. de Castro Laila V. de Almeida Mariana Santos Cardoso Fabricio M. Silva Oliveira Denise S. Nogueira João Luis Reis-Cunha Luisa M.D. Magalhaes Bin Zhan Maria Elena Bottazzi Peter J. Hotez Lilian L. Bueno Daniella Castanheira Bartholomeu Ricardo T. Fujiwara 《Vaccine》2021,39(2):394-401
An estimated 400 million people are infected by parasites of the genus Ascaris and the existing control measures are inefficient. Vaccine development using B cell antigens is a promising strategy for increased protection against this parasite. The present study aimed at developing a chimeric protein capable of conferring protection against infection by Ascaris sp. For this purpose, we performed B-cell epitope predictions on previously described vaccine candidate proteins from Ascaris suum and the corresponding peptides were used to construct a chimeric protein. Female BALB / c mice were immunized subcutaneously in three doses at 10 day intervals with a vaccine formulation comprised of the chimeric protein together with monophosphoryl lipid A (MPLA). Control groups included protein alone, MPLA, or PBS. After challenge infection, animals vaccinated with chimeric protein plus MPLA showed a reduction of 73.54% of larval load in the lung compared to control group animals. Animals immunized with chimeric protein plus MPLA also display higher IgG response and a reduction in lung inflammation. Our study highlights how chimeric proteins containing more than one B cell epitope can enhance immune protection against helminthic infection and offer new approaches to the development of Ascaris vaccines. 相似文献
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Positive correlation of insulin-like growth factor-II with proliferating cell index in patients with colorectal neoplasia. 总被引:2,自引:0,他引:2
Ronghua Zhao Mariana Berho Juan Nogueras Dana Sands Eric Weiss Steven Wexner Francis M Giardiello Marcia Cruz-Correa 《Cancer epidemiology, biomarkers & prevention》2005,14(7):1819-1822
BACKGROUND: Insulin-like growth factor-II (IGF-II) stimulates cell proliferation and is considered a potential risk factor for colorectal cancer. Tumor levels of IGF-II seem to positively correlate with colorectal cancer cell proliferation. This investigation examined the association of circulating IGF-II to the proliferating cell index (PCI) of tumor and matched normal mucosa in patients with colorectal neoplasia. METHODS: Circulating IGF-II level (ng/mL) was determined in the peripheral blood plasma by ELISA. The proliferating cells in tumor or matched normal mucosa were immunohistochemically stained using the primary antibody against Ki-67. Computer image analysis was used and PCI was expressed as the percentage of Ki-67-positive cells/total counted cells. RESULTS: Sixty-four patients were evaluated; 45 had colorectal neoplasia (27 males/18 females; mean age, 66.8 +/- 11.8 years) and 19 had hyperplastic polyps (6 males and 13 females; mean age, 58.4 +/- 14.4 years). Among patients with colorectal neoplasia, blood IGF-II levels were positively correlated with PCI in the matched normal mucosa (r = 0.46, P < 0.05) but not in the tumor. In patients with hyperplastic polyps, blood IGF-II levels were not correlated with the PCI in the polyps. Blood IGF-II levels were higher in colorectal cancer patients with Dukes' C/D stage (P < 0.01) or with positive lymph nodes (P < 0.01). CONCLUSION: Circulating IGF-II positively correlated with PCI in normal colonic mucosa of patients with colorectal neoplasia, suggesting that IGF-II may have a role in initiating the carcinogenic pathway by stimulating cell proliferation. Blood IGF-II was increased in advanced colorectal cancer, indicating that it might enhance colorectal cancer progression and be a useful marker of poor prognosis. 相似文献
35.
Angiogenesis in the bone marrow of patients with breast cancer. 总被引:3,自引:0,他引:3
Mariana Chavez-Macgregor Alejandro Aviles-Salas Dan Green Adolfo Fuentes-Alburo Celedonio Gómez-Ruiz Alvaro Aguayo 《Clinical cancer research》2005,11(15):5396-5400
PURPOSE: Pathologic angiogenesis has been correlated with tumor growth, dissemination, metastasis, and prognosis in solid tumors including breast cancer. Angiogenesis has also been implicated in the pathophysiology of, and shown to be a therapeutic target in tumors arising in the bone marrow. The status of angiogenesis in the bone marrow of breast cancer patients is unknown. The aim of this study was to estimate the extent of bone marrow angiogenesis in this subset of patients. EXPERIMENTAL DESIGN: We studied 42 women with breast cancer in whom a bone marrow biopsy was done. Bone marrow samples were sorted according to their infiltration status by breast cancer cells. In all bone marrow sections, blood vessels were highlighted by staining endothelial cells with an antibody directed against the CD34-related antigen. A hematopathologist blind to the status of infiltration of breast cancer did the bone marrow vessel count. RESULTS: Nineteen patients (45%) had bone marrow metastasis. The bone marrow microvessel density was significantly higher in patients with bone marrow metastases compared with patients without bone marrow metastases (P < 0.0005). Median bone marrow microvessel density was 2 for the negative bone marrow group, and 15 for the positive bone marrow group. An increased microvessel density was correlated with presence of disease at last follow-up. CONCLUSIONS: This is the first study showing that bone marrow microvessel density is significantly higher in breast cancer patients with bone marrow metastases, when compared with breast cancer patients without evidence of bone marrow metastatic disease. Further research is needed to shed light into the prognostic and therapeutic relevance of this finding. 相似文献
36.
Ana-Maria Prelipcean Andreea Iosageanu Alexandra Gaspar-Pintiliescu Lucia Moldovan Oana Craciunescu Ticuta Negreanu-Pirjol Bogdan Negreanu-Pirjol Raul-Augustin Mitran Mariana Marin Ugo DAmora 《Materials》2022,15(10)
Over the past years, research attention has been focusing more on waste-derived, naturally derived, and renewable materials, in the view of a more sustainable economy. In this work, different topical formulations were obtained from the valorization of marine and agro-industrial by-products and the use of Carbopol 940 as gelling agent. In particular, the combination of extracts obtained from the marine snail, Rapanosa venosa, with Cladophora vagabunda and grape pomace extracts, was investigated for wound healing purposes. Rapana venosa has demonstrated wound healing properties and antioxidant activity. Similarly, grape pomace extracts have been shown to accelerate the healing process. However, their synergic use has not been explored yet. To this aim, four different formulations were produced. Three formulations differed for the presence of a different extract of Rapana venosa: marine collagen, marine gelatin, and collagen hydrolysate, while another formulation used mammalian gelatin as further control. Physico-chemical properties of the extracts as well as of the formulations were analyzed. Furthermore, thermal stability was evaluated by thermogravimetric analysis. Antioxidant capacity and biological behavior, in terms of cytocompatibility, wound healing, and antimicrobial potential, were assessed. The results highlighted for all the formulations (i) a good conservation and thermal stability in time, (ii) a neutralizing activity against free radicals, (iii) and high degree of cytocompatibility and tissue regeneration potential. In particular, collagen, gelatin, and collagen hydrolysate obtained from the Rapana venosa marine snail represent an important, valuable alternative to mammalian products. 相似文献
37.
Konrath EL Neves BM Lunardi PS Passos Cdos S Simões-Pires A Ortega MG Gonçalves CA Cabrera JL Moreira JC Henriques AT 《Journal of ethnopharmacology》2012,139(1):58-67
Ethnopharmacological relevance
The study was aimed at evaluating medicinal and therapeutic potentials of two Lycopodiaceae species, Lycopodium clavatum (L.) and Lycopodium thyoides (Humb. & Bonpl. ex Willd), both used in South American folk medicine for central nervous system conditions. Alkaloid extracts were evaluated for chemical characterization, acetylcholinesterase and antioxidant activities.Materials and methods
The alkaloid extracts obtained by alkaline extraction were determined for each species by GC/MS examination. The evaluation of the anticholinesterase and the antioxidant activities of the extracts were tested by determining in vitro and ex vivo models. Effects on acetylcholinesterase (AChE) were tested in vitro using rat brain homogenates and ex vivo after a single administration (25, 10 and 1 mg/kg i.p.) of the alkaloid extracts in mice. The in vitro antioxidant effects were tested for the 2-deoxyribose degradation, nitric oxide (NO) interaction, 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity and total reactive antioxidant potential (TRAP). After an acute administration (25 and 10 mg/kg i.p.) of the extracts in middle-aged (12 months) mice, the antioxidant effects were estimated through the thiobarbituric acid reactive substances test (TBARS), and the antioxidant enzymes activities for catalase (CAT) and superoxide dismutase (SOD) were measured.Results
AChE activity was inhibited in vitro by the alkaloid-enriched extracts of both Lycopodium species in a dose and time-dependent manner in rat cortex, striatum and hippocampus. A significant inhibition was also observed in areas of the brain after acute administration of extracts, as well as decreased lipid peroxidation and increased CAT activity in the cortex, hippocampus and cerebellum. A moderate antioxidant activity was observed in vitro for the extracts. Chemically, the main alkaloids found for the two species were lycopodine and acetyldihidrolycopodine.Conclusion
This study showed that the biological properties of the folk medicinal plants Lycopodium clavatum and Lycopodium thyoides include AChE inhibitory activity and antioxidant effects, two possible mechanisms of action in Alzheimer's related processes. 相似文献38.
Mariana Fernndez-Lizrraga Julieta García-Lpez Sandra E. Rodil Rosa María Ribas-Aparicio Phaedra Silva-Bermudez 《Materials》2022,15(15)
Biomaterials with adequate properties to direct a biological response are essential for orthopedic and dental implants. The surface properties are responsible for the biological response; thus, coatings with biologically relevant properties such as osteoinduction are exciting options to tailor the surface of different bulk materials. Metal oxide coatings such as TiO2, ZrO2, Nb2O5 and Ta2O5 have been suggested as promising for orthopedic and dental implants. However, a comparative study among them is still missing to select the most promising for bone-growth-related applications. In this work, using magnetron sputtering, TiO2, ZrO2, Ta2O5, and Nb2O5 thin films were deposited on Si (100) substrates. The coatings were characterized by Optical Profilometry, Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, X-ray Photoelectron Spectroscopy, X-ray Diffraction, Water Contact Angle measurements, and Surface Free Energy calculations. The cell adhesion, viability, proliferation, and differentiation toward the osteoblastic phenotype of mesenchymal stem cells plated on the coatings were measured to define the biological response. Results confirmed that all coatings were biocompatible. However, a more significant number of cells and proliferative cells were observed on Nb2O5 and Ta2O5 compared to TiO2 and ZrO2. Nevertheless, Nb2O5 and Ta2O5 seemed to induce cell differentiation toward the osteoblastic phenotype in a longer cell culture time than TiO2 and ZrO2. 相似文献
39.
Frutuoso C Henriques I Pazos I Abraul E Pego A Belo J Campos O Gervásio H de Oliveira C 《European journal of gynaecological oncology》2007,28(6):447-450
Primary chemotherapy is increasingly used in patients with large operable breast cancer. Docetaxel and epirubicin are the most active agents in breast cancer treatment. PURPOSE: To evaluate clinical response rate, breast conserving surgery and pathological response rate in patients with large operable breast cancer treated with docetaxel followed by docetaxel and epirubicin as primary chemotherapy. PATIENTS AND METHODS: Patients with operable breast cancer more than 3 cm in the longest diameter with T2N0, T2N1 and T3N0 disease were enrolled. Patients were treated with three cycles of docetaxel 100 mg/m2 followed by three cycles of docetaxel 75 mg/m2 and epirubicin 90 mg/m2 prior to surgery. RESULTS: Sixty-five patients were enrolled between 09/2002 and 12/2005. The median age was 48.9 years and 72.3% were premenopausal. Median tumour size was 4.26 cm, 10.8% were T3 tumours and 38.5% had clinical positive lymph nodes. Of the tumours 58.5% were grade 1/2, 33.9% ER positive and 21.5% c-erb negative. All six cycles were administered to 62 patients; six cycles were delayed and five had dose reductions. Complete clinical response occurred in 41.5% of patients and partial response in 49.2%. Breast conserving surgery was performed in 30% of patients however it was feasible in 57%. Complete pathological response occurred in both primary tumour and nodes in 28%, and in 34% just in the primary tumour. Nine percent of cases had neutropenia and 7.7% febrile neutropenia, and two cases had a hypersensitivity reaction to docetaxel. One associated treatment death occurred. CONCLUSION: Docetaxel followed by epirubicin and docetaxel as primary chemotherapy results in a high clinical and pathological response rate. The majority of adverse events were predictable and manageable. 相似文献