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Colorectal cancer can develop through molecular, chromosomal, and epigenetic cumulative changes that transform the normal intestinal epithelium into the colorectal polyps, called conventional adenomas (CAs) or serrated polyps (SPs), recognized as precursors of invasive colorectal neoplasia. These benign lesions need to explore the morphology, histological diagnosis, and biomarkers profile to accurately characterize lesions with potential for evolution to cancer. This study aimed to correlate the immunohistochemical expression of Parkin and Adenomatous Polyposis Coli (APC; tumor suppressors), Human Apurinic/Apyrimidinic endonuclease 1 (APE1), and B-cell lymphoma-extra-large (Bcl-xL; oncogenic proteins) in sporadic colorectal polyps with clinical, endoscopic, and diagnostic data. Immunohistochemical analysis was performed on tissue microarray samples of 306 polyps. Based on the Allred score, the expressions were graduated in the cytoplasm and nucleus of superficial and cryptic cells. There was higher Parkin nuclear expression (p=0.006 and 0.010) and APC cytoplasmic expression in cryptic cells (p<0.001) in SPs. CAs, APE1 (p<0.001) and Bcl-xL (p<0.001) were more expressed in the nuclei and cytoplasms, respectively. These results are related to the biological role proposed for these proteins in cellular functions. They can contribute to the diagnosis criteria for polyps and improve the knowledge of biomarkers that could predict cancer development:  相似文献   
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Length–weight relationships (TW = a TLb) were estimated for fish species caught by bottom shrimp trawl north of Santa Catarina Island (Brazil) from October 2003 to September 2004. For three of the species this is the first LWR data in Brazil.  相似文献   
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Oseltamivir phosphate is a widely used anti-influenza sialidase inhibitor. Sialylation, governed by sialyltransferases and sialidases, is strongly implicated in the oncogenesis and progression of breast cancer. In this study we evaluated the biological behavior of canine mammary tumor cells upon oseltamivir phosphate treatment (a sialidase inhibitor) in vitro and in vivo. Our in vitro results showed that oseltamivir phosphate impairs sialidase activity leading to increased sialylation in CMA07 and CMT-U27 canine mammary cancer cells. Surprisingly, oseltamivir phosphate stimulated, CMT-U27 cell migration and invasion capacity in vitro, in a dose-dependent manner. CMT-U27 tumors xenograft of oseltamivir phosphate-treated nude mice showed increased sialylation, namely α2,6 terminal structures and SLe(x) expression. Remarkably, a trend towards increased lung metastases was observed in oseltamivir phosphate-treated nude mice. Taken together, our findings revealed that oseltamivir impairs canine mammary cancer cell sialidase activity, altering the sialylation pattern of canine mammary tumors, and leading, surprisingly, to in vitro and in vivo increased mammary tumor aggressiveness.  相似文献   
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Cryptococcal meningitis (CM) remains as common life-threatening AIDS-defining illness mainly in resource-limited settings. Previous reports suggested that baseline cytokine profiles can be associated to fungal burden and clinical outcome. This study aimed to evaluate the baseline cytokine profiles in AIDS patients with CM and its relation with the outcome at weeks 2 and 10. Thirty AIDS patients with CM diagnosed by cerebrospinal fluid (CSF) Cryptococcus neoformans positive culture, India ink stain and cryptococcal antigen test were prospectively evaluated. As controls, 56 HIV-infected patients without CM and 48 non-HIV individuals were included. Baseline CSF and sera levels of IL-2, IL-4, IL-8, IL-10, IL-12p40, IL-17A, INF-γ and TNF-α were measured by ELISA. Of 30 CM patients, 24 (80%) were male, median age of 38.1. The baseline CSF high fungal burden and positive blood culture were associated with a positive CSF culture at week 2 (p = 0.043 and 0.029). Most CSF and sera cytokines presented higher levels in CM patients than control subjects (p < 0.05). CSF levels of IL-8, IL-12p40, IL-17A, TNF-α, INF-γ and sera TNF-α were significantly higher among survivors at weeks 2 and 10 (p < 0.05). Patients with increased intracranial pression exhibited CSF IL-10 high levels and poor outcome at week 10 (p = 0.032). Otherwise, baseline CSF log10 IFN-γ and IL-17A were negatively correlated with fungal burden (r = -0.47 and -0.50; p = 0.0175 and 0.0094, respectively). The mortality rate was 33% (10/30) at week 2 and 57% (17/30) at week 10. The severity of CM and the advanced immunodeficiency at admission were related to a poor outcome in these patients. Otherwise, the predominant Th1 cytokines profile among survivors confirms its pivotal role to infection control and would be a prognostic marker in cryptococcal meningitis.  相似文献   
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Cashew apple is a tropical pseudofruit consumed as juice due to its excellent nutritional and sensory properties. In spite of being well known for its important antioxidant properties, the cashew apple has not been thoroughly investigated for its therapeutic potential. Thereby, this study evaluated the antioxidant capacity, anti-inflammatory, and wound-healing activities of cashew apple juice. Juices from ripe and immature cashew apples were analyzed for antioxidant, anti-inflammatory, and wound-healing properties. Those were evaluated in murine models of xylene-induced ear edema and wound excision. Swiss mice were treated with cashew juice by gavage. Edema thickness was measured and skin lesions were analyzed by planimetry and histology. Both antioxidant content and total antioxidant activity were higher in ripe cashew apple juice (RCAJ) than in unripe cashew apple juice (UNCAJ). The UNCAJ presented the main anti-inflammatory activity by a significant inhibition of ear edema (66.5%) when compared to RCAJ (10%). Moreover, UNCAJ also showed the best result for wound contraction (86.31%) compared to RCAJ (67.54%). Despite of higher antioxidant capacity, RCAJ did not promote better anti-inflammatory, and healing responses, which may be explained by the fact that treatment increased antioxidants level leading to a redox “imbalance” turning down the inflammatory response modulation exerted by reactive oxygen species (ROS). The results suggest that UNCAJ presents a greater therapeutic activity due to a synergistic effect of its phytochemical components, which improve the immunological mechanisms as well as an optimal balance between ROS and antioxidants leading to a better wound healing process.  相似文献   
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Crude extract from the sponge Cinachyrella apion showed cross-reactivity with the polyclonal antibody IgG anti-CvL (Cliona varians lectin) and also a strong haemagglutinating activity towards human erythrocytes of all ABO groups. Thus, it was submitted to acetone fractionation, IgG anti-deglycosylated CvL Sepharose affinity chromatography, and Fast Protein Liquid Chromatography (FPLC-AKTA Purifier) gel filtration on a Superose 6 10/300 column to purify a novel lectin. C. apion lectin (CaL) agglutinated all types of human erythrocytes with preference for papainized type A erythrocytes. The haemagglutinating activity is independent of Ca2+, Mg2+ and Mn2+ ions, and it was strongly inhibited by the disaccharide lactose, up to a minimum concentration of 6.25 mM. CaL molecular mass, determined by FPLC-gel filtration on a Superose 12 10/300 column and SDS gel electrophoresis, was approximately 124 kDa, consisting of eight subunits of 15.5 kDa, assembled by hydrophobic interactions. The lectin was heat-stable between 0 and 60 °C and pH-stable. The N-terminal amino acid sequence of CaL was also determined and a blast search on amino acid sequences revealed that the protein showed similarity only with a silicatein. Leishmania chagasi promastigotes were agglutinated by CaL and this activity was abolished by lactose, indicating that lactose receptors could be presented in this parasite stage. These findings are indicative of the potential biotechnological application of CaL as diagnostic of pathogenic protozoa.  相似文献   
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