Antiproliferative effects of lectins from Canavalia ensiformis and Canavalia brasiliensis in human leukemia cell lines

AbstractThe antiproliferative activity of lectins Canavalia ensiformis (ConA) and Canavalia brasiliensis (ConBr) were studied using human leukemia MOLT-4 and HL-60 cell lines. It was revealed that both ConA and ConBr were markedly cytotoxic to cells using MTT and NAC assays. The IC50 values were approximately 3 and 20μg/mL for ConA and ConBr, respectively, for both MOLT-4 and HL-60 cells. However, in normal human peripheral blood lymphocytes, the lectins were not cytotoxic, even when tested at concentrations as high as 200μg/ml. Using comet assay, the lectins produced a rate of DNA damage exceeding 80% in MOLT-4 and HL-60 cells. Fluorescence analysis revealed the morphology characteristic of apoptosis, with low concentrations of apoptotic bodies and fragmented DNA (5μg/ml). Flow cytometric analysis demonstrated an accumulation of cells in the sub-G1 cell cycle that is characteristic of DNA fragmentation, and a decrease in membrane integrity at high concentrations. Lastly, we evaluated the alterations in mitochondrial potential that reduced after treatment with lectins. Our results indicate that ConA and ConBr inhibited cell proliferation selectively in tumor cells and that apoptosis was the main death mechanism. Therefore, lectins can be considered a class of molecules with a high antitumor activity potential

Development of an active orthosis prototype for lower limbs

ARAUJO, Márcio V. ; ALSINA, Pablo J. ; MEDEIROS, Adelardo A. D. ; PEREIRA, Jonathan P.P. ; DOMINGOS, Elber C. ; ARAÚJO, Fábio M.U. ; SILVA, Jáder S. . Development of an Active Orthosis Prototype for Lower Limbs. In: INTERNATIONAL CONGRESS OF MECHANICAL ENGINEERING, 20., 2009, Gramado, RS. Proceedings… Gramado, RS: [s. n.], 2009This paper presents the development of a prototype of an active orthosis for lower limbs. The proposed orthosis is an orthopedical device with the main objective of providing walking capacity to people with partial or total loss of limbs movements. In order to design the kinematics, dynamics and the mechanical characteristics of the prototype, the biomechanics of the human body was analized. The orthosis was projected to reproduce the movements of human gait. The movements of the joints of the orthosis are controlled by DC motors equipped with mechanical reductions, whose purpose is to reduce rotational speed and increase the torque, thus generating smooth movements. An embedded electronic system for sensory data acquisition and motor control was projected. The gait movements of the orthosis will be controlled by high level commands from a human-machine interface based on processings of electroencephalogram signals, speech recognition or joystic

Latex peptidases of Calotropis procera for dehairing of leather as an alternative to environmentally toxic sodium sulfide treatment

Dehairing of crude leather is a critical stage performed at the beginning of its processing to obtain industrially useful pieces. Tanneries traditionally apply a chemical process based on sodium sulfide. Since this chemical reactive is environmentally toxic and inefficiently recycled, innovative protocols for reducing or eliminating its use in leather depilation are welcomed. Therefore, latex peptidases from Calotropis procera (CpLP) and Cryptostegia grandiflora (CgLP) were assayed for this purpose. Enzyme activity on substrates representative of skin such as hide powder azure (UHPA), elastin (UE), azocollagen (UAZOCOL), keratin (UK), and epidermis (UEP) was determined, while depilation activity was assayed on cow hide. Only CpLP was active against keratin (13.4 UK) and only CgLP was active against elastin (0.12 UE). CpLP (93.0 UHPA, 403.6 UAZOCOL, 36.3 UEP) showed higher activity against the other substrates than CgLP (47.6 UHPA, 261.5 UAZOCOL, 8.5 UEP). In pilot assays, CpLP (0.05% w/v with sodium sulfite 0.6% w/v as activator) released hairs from cow hide pieces. Macroscopic and microscopic analyses of the hide revealed that the dehairing process was complete and the leather structure was preserved. The proteolytic system of C. procera is a suitable bioresources to be exploited by tanneries.Fil: Lopez, Laura Maria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Viana, Carolina A.. Universidade Estadual Do Ceara; BrasilFil: Errasti, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Garro, María Laura. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Martegani, José Eduardo. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Mazzilli, German Ariel. Instituto Nacional de Tecnología Industrial. Centro de Investigación y Desarrollo del Cuero. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Centíficas. Centro de Investigación y Desarrollo del Cuero; ArgentinaFil: Freitas, Cléverson D. T.. Universidade Estadual Do Ceara; BrasilFil: Araújo, Ídila M. S.. EMBRAPA Agrotropical; BrasilFil: da Silva, Rafaela O.. Universidade Estadual Do Ceara; BrasilFil: Ramos, Márcio V.. Universidade Estadual Do Ceara; Brasi

Immunophenotypic features of tumor infiltrating lymphocytes from mammary carcinomas in female dogs associated with prognostic factors and survival rates

<p>Abstract</p> <p>Background</p> <p>The immune system plays an important role in the multifactorial biologic system during the development of neoplasias. However, the involvement of the inflammatory response in the promotion/control of malignant cells is still controversial, and the cell subsets and the mechanisms involved are poorly investigated. The goal of this study was to characterize the clinical-pathological status and the immunophenotyping profile of tumor infiltrating lymphocytes and their association with the animal survival rates in canine mammary carcinomas.</p> <p>Methods</p> <p>Fifty-one animals with mammary carcinomas, classified as carcinomas in mixed tumors-MC-BMT = 31 and carcinomas-MC = 20 were submitted to systematic clinical-pathological analysis (tumor size; presence of lymph node and pulmonary metastasis; clinical stage; histological grade; inflammatory distribution and intensity as well as the lymphocytic infiltrate intensity) and survival rates. Twenty-four animals (MC-BMT = 16 and MC = 8) were elected to the immunophenotypic study performed by flow cytometry.</p> <p>Results</p> <p>Data analysis demonstrated that clinical stage II-IV and histological grade was I more frequent in MC-BMT as compared to MC. Univariate analysis demonstrated that the intensity of inflammation (moderate/intense) and the proportion of CD4⁺(≥ 66.7%) or CD8⁺T-cells (<33.3%) were not associated with worse survival rate. Multivariate analysis demonstrated that only lymphocytic infiltrate intensity ≥ 600 (<it>P </it>= 0.02) remained as independent prognostic factor. Despite the clinical manifestation, the lymphocytes represented the predominant cell type in the tumor infiltrate. The percentage of T-cells was higher in animals with MC-BMT without metastasis, while the percentage of B-lymphocytes was greater in animals with metastasized MC-BMT (<it>P </it>< 0.05). The relative percentage of CD4⁺T-cells was significantly greater in metastasized tumors (both MC-BMT and MC), (<it>P </it>< 0.05) while the proportion of CD8⁺T-cells was higher in MC-BMT without metastasis. Consequently, the CD4⁺/CD8⁺ratio was significantly increased in both groups with metastasis. Regardless of the tumor type, the animals with high proportions of CD4⁺and low CD8⁺T-cells had decreased survival rates.</p> <p>Conclusion</p> <p>The intensity of lymphocytic infiltrate and probably the relative abundance of the CD4⁺and CD8⁺T-lymphocytes may represent important survival prognostic biomarkers for canine mammary carcinomas.</p