1,747 research outputs found

    Endothelial Progenitor Cells in Breast Cancer

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    EditorialRecent evidences demonstrated the importance of bone marrow derived Endothelial Progenitor Cells (EPC), in the contribution to postnatal physiological and pathological neovascularization, and in tumor growth and angiogenesis. These cells are recruited undifferentiated, in response to systemic or chemoatractive signals, such as Vascular Endothelial Growth Factor (VEGF), they lodge in the growing or lesioned tissue and differentiate into endothelial cells in response to local stimuli and cell-cell interactions. The extent and the significance of the EPCs contribution for the growing of most tumors, including those of the breast, are still not fully defined. We analyzed the peripheral blood of breast cancer patients and found that they have circulating EPCs. We also found an association between expression of AC133+Kdr+ and VEGF plasma levels in these patients. Strategies to impair the mobilization and incorporation of EPCs into breast tumors may contribute to halt the growth of these tumors

    Machinery for artificial emotions

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    We present a preliminary definition and theory of artificial emotion viewed as a sequential process comprising the appraisal of the agent global state, the generation of an emotion-signal, and an emotion-response. This theory distinguishes cognitive from affective appraisal on an architecture-grounded basis. Affective appraisal is performed by the affective component of the architecture; cognitive appraisal is performed by its cognitive component. A scheme for emotion classification with seven dimensions is presented. Among them, we emphasize the roles played by emotions and the way these roles are fulfilled. It is shown how emotions are generated, represented, and used in the Salt & Pepper architecture for autonomous agents (Botelho, 1997). Salt & Pepper is a specific architecture comprising an affective engine, a cognitive and behavioral engine, and an interruption manager. Most properties of the cognitive and behavioral engine rely upon a hybrid associative, schema-based long-term memory. In Salt & Pepper, emotion-signals, represented by label, object of appraisal, urgency, and valence, are generated by the affective engine through the appraisal of the agent's global state. For each emotion-signal there are several nodes stored and interconnected in long-term memory. Each of these nodes contains an emotion response that may be executed when an emotion-signal is generated. Emotion intensity relates to the activation of the node. It is shown that the Salt & Pepper architecture for autonomous agents exhibits several properties usually related to emotion: state and mood congruence, compound emotions, autonomic emotion-responses, and different emotion-responses to the same stimulus including the generation of different motives. The implementation of a concrete example is described.info:eu-repo/semantics/acceptedVersio

    The Computer question in Brazil : high technology in a developing society : papers

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    "July 1985."Includes bibliographical referencesIntroduction / Antonio Botelho and Peter H. Smith -- High Technology or Self Reliance? : Brazil Enters the Computer Age / Simon Schwartzman -- Varieties of Nationalism : The Politics of the Brazilian Computer Industry / Peter Evans -- The Brazilian Computer Industry : Performance and Perspectives / Paulo Bastos Tigr

    Bladder cancer and urinary Schistosomiasis in Angola

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    J Nephrol Res. Author manuscript; available in PMC 2015 Jul 9. Disponível em: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4497783/Schistosomiasis haematobia is among the most prevalent parasitosis in Angola. The pathology is characterized by serious and irreversible lesions in the urogenital tract induced by chronic infection with the parasite that can eventually lead to squamous cell carcinoma of the bladder. Considering the frequency and severe morbidity observed, even in younger ages, the purpose of this study was to assess the prevalence and morbidity of S. haematobium infection in Angola. A baseline survey was conducted between November 2007 and February 2008. A randomly sample of 300 inhabitants aged 15 to 75 years old participated in this study. Prevalence of S. haematobium infection was 71.7 % (215/300). Infection was higher in females (56.3 %) but no significant difference was found in prevalence and intensity between gender and age groups. The predominant selfreported symptoms were dysuria (91.2 %), hypogastralgia (88.7 %) and haematuria (87.1%) and these symptoms were strongly associated with S. haematobium infection (p<0.05). Ultrasound and cystoscopy examinations performed in a sub-sample of 29 individuals revealed pathological conditions at the urinary tract in all examined. Considering the high prevalence of S. haematobium infections in Angola and schistosomiasis-associated bladder cancer, our results indicate that this population should be targeted for follow up and implementation of measures for treatment and control of schistosomiasis

    Estrogen catechols detection as biomarkers in schistosomiasis induced cancer and infertility

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    Urogenital schistosomiasis is a chronic infection caused by the human blood fluke Schistosoma haematobium. Schistosomiasis haematobium is a known risk factor for cancer leading to squamous cell carcinoma of the urinary bladder (SCC). This is a neglected tropical disease endemic in many countries of Africa and the Middle East. Schistosome eggs produce catechol-estrogens. These molecules are metabolized to active quinones that cause alterations in DNA (leading in other contexts to breast or thyroid cancer). Our group have shown that schistosome egg associated catechol estrogens induce tumor-like phenotypes in urothelial cells, originated from parasite estrogen-host cell chromosomal DNA adducts and mutations. Here we review recent findings on the role of estrogen-DNA adducts and how their shedding in urine may be prognostic of schistosome infection and/or represent potential biomarkers for urogenital schistosomiasis associated bladder cancer and infertility.This work was financed by FEDER - Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 - Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through FCT - Fundação para a Ciência e a Tecnologia/ Ministério da Ciência, Tecnologia e Inovação in the framework of the project "Institute for Research and Innovation in Health Sciences" (POCI-01-0145-FEDER-007274).info:eu-repo/semantics/publishedVersio

    Progesterone in breast cancer angiogenesis

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    The involvement of steroid hormones in breast carcinogenesis is well established. Recent evidence suggests that angiogenesis can be regulated by hormones. Both oestrogen and progesterone have been implicated in the angiogenic process of hormone-dependent cancers, such as breast cancer. Vascular Endothelial Growth Factor (VEGF) is a growth factor involved in angiogenesis in breast cancer that is up-regulated by estrogens. In our study we evaluated the role of progesterone in the expression of this angiogenic growth factor commonly up-regulated in breast cancer. Our findings indicate that progesterone activates an angiogenic pathway involving VEGF stimulation. The elucidation of specific angiogenic pathways promoted by progesterone can raise new therapeutic targets at least in a subset of breast cancers responsive to progesterone

    Schistosoma mansoni infection impairs reproduction in mice

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    AIM: To study the effect of S. mansoni infection in fertility using a mouse model. BACKGROUND: - Our group is listed in the Top 10 most publishing authors in the field of schistosomiasis as a cause of infertility; - Estrogen-like molecules produced by schistosomes haematobia and mansoni induce hormonal imbalances in infected persons; - These estrogenic metabolites down-regulate Estrogen Receptor in an in vitro model; - We have identified these estrogenic metabolites as catechol-estrogens (oxidative metabolites derived from estrogens); - These catechol-estrogens were found to be associated with infertility in women infected with S. haematobium.N/

    Epidemiology and pathology of bovine schistosomiasis in Mozambique

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    AIM: To study the epidemiology and pathology of bovine schistosomiasis in Mozambique. BACKGROUND: - Bovine schistosomiasis is of great importance in Africa. It is caused by Schistosoma bovis; - In bovines the symptoms are similar to humans, mainly intestinal, hepato-splenic, vesical and genital; - It has been shown to be endemic through all Africa and in some Mediterranean countries (Portugal, Spain, Italy, Iraque and Israel); - Hybrids of S. haematobium and S. bovis are known to infect humans.N/

    Anti-cancer potential of Fasciola hepatica extracts

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    Fascioliasis is a food borne disease caused by infection with a liver fluke termed Fasciola (F.) hepatica. Fascioliasis, as a neglected tropical disease, commonly affects poor people from developing countries. It has been estimated that at least 2.6 million people are infected with fascioliasis worldwide. According to the International Agency for Research on Cancer, two other liver flukes Opistorchis viverrini and Clonorchis sinensis) have been recognized as definitive causes of cancer (IARC, 2012). On the other hand even long-lasting and/ or repeated F. hepatica infections have not been associated with cancer, so far. There are any known causative associations between this parasite and cholangiocarcinoma or liver cancer.N/

    Could Estradiol be used as a biomarker of infection in Schistosoma haematobium infected patients?

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    Urogenital schistosomiasis is a chronic infection caused by the human blood fluke Schistosoma haematobium. Schistosomiasis haematobia is a known risk factor for cancer leading to squamous cell carcinoma of the urinary bladder (SCC). This is a neglected tropical disease endemic in many countries of Africa and the Middle East. Schistosome eggs produce catechol-estrogens. These estrogenic molecules are metabolized to active quinones that cause alterations in DNA (leading in other contexts to breast or thyroid cancer). Our group has shown that schistosome egg associated catechol estrogens induce tumor-like phenotypes in urothelial cells, originated from parasite estrogen-host cell chromosomal DNA adducts and mutations. Also we have demonstrated that these molecules are detected as Estradiol in sera of infected patients.N/
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