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Human eosinophil adhesion and degranulation stimulated with eotaxin and RANTES in vitro: Lack of interaction with nitric oxide

Lintomen, Letícia; Franchi, Gilberto; Nowill, Alexandre; Condino-Neto, Antonio; de Nucci, Gilberto; Zanesco, Angelina; Antunes, Edson
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
35.96%
Background: Airway eosinophilia is considered a central event in the pathogenesis of asthma. The toxic components of eosinophils are thought to be important in inducing bronchial mucosal injury and dysfunction. Previous studies have suggested an interaction between nitric oxide (NO) and chemokines in modulating eosinophil functions, but this is still conflicting. In the present study, we have carried out functional assays (adhesion and degranulation) and flow cytometry analysis of adhesion molecules (VLA-4 and Mac-1 expression) to evaluate the interactions between NO and CC-chemokines (eotaxin and RANTES) in human eosinophils. Methods: Eosinophils were purified using a percoll gradient followed byimmunomagnetic cell separator. Cell adhesion and degranulation were evaluated by measuring eosinophil peroxidase (EPO) activity, whereas expression of Mac-1 and VLA-4 was detected using flow cytometry. Results: At 4 h incubation, both eotaxin (100 ng/ml) and RANTES (1000 ng/ml) increased by 133% and 131% eosinophil adhesion, respectively. L-NAME alone (but not D-NAME) also increased the eosinophil adhesion, but the co-incubation of L-NAME with eotaxin or RANTES did not further affect the increased adhesion seen with chemokines alone. In addition...

Cultura de celulas vero sobre membranas de poli(hidroxibutirato-co-hidroxivalerato) (phbv) tratadas por plasma gasoso; Vero cells culture on poly poli(hydroxybutyrate-co-hydroxyvalerate) (phbv) membranes treated by gaseous plasma

Carolina Lucchesi
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/07/2006 PT
Relevância na Pesquisa
35.93%
O copolímero Poli(hidroxibutirato-co-hidroxivalerato) (PHBV) tem sido intensamente estudado como substrato para a engenharia de tecidos, sendo conhecido como um poliéster hidrofóbico. A modificação da superfície por plasma é uma técnica efetiva e econômica para os materiais e tem ganhado crescente interesse da engenharia biomédica, por melhorar a biocompatibilidade da superfície. Neste estudo, avaliou-se as vantagens da modificação da superfície de membranas de PHBV tratadas por plasma de Oxigênio e Nitrogênio a fim de acelerar o processo de adesão e proliferação celular. O PHBV foi dissolvido em c1oreto de metileno à temperatura ambiente. Membranas de PHBV foram submetidas ao tratamento de plasma de Oxigênio e Nitrogênio, através de um gerador de plasma. As membranas foram esterilizadas por radiação UV por 30 min e colocadas em placas de 96 poços. Células Vero foram semeadas sobre as membranas, sendo determinada a proliferação celular sobre as matrizes, a citotoxicidade e adesão celular. Após 2, 24,48 e 120h de incubação, o crescimento e proliferação dos fibroblastos foram observados por microscopia eletrônica de varredura (MEV). As análises das membranas indicaram que o tratamento por plasma aumentou o ângulo de contato e a rugosidade...

Estudo da inibição do oxido nitrico sobre funções de eosinofilos humanos estimulados com eotaxina e RANTES in vitro; Study of nitric oxide inhibition in human eosinophil functions stimulated in vitro with eotaxin and RANTES

Leticia Lintomen
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/08/2008 PT
Relevância na Pesquisa
26.2%
Os eosinófilos participam da patogênese de várias doenças inflamatórias, incluindo infecções parasíticas e doenças alérgicas. Dentre as doenças alérgicas, a eosinofilia tem presença marcante na asma. Atualmente, a asma afeta 300 milhões de indivíduos no mundo, sendo considerada um problema de saúde pública mundial. A asma é uma doença inflamatória crônica que envolve interações entre fatores externos e genéticos, e tem como características principais a inflamação pulmonar e a hiperresponsividade brônquica. O recrutamento de eosinófilos para as vias aeríferas contribui para o caráter crônico da asma. A migração de eosinófilos para o tecido inflamado é um processo complexo, que é regulado por numerosos fatores, incluindo citocinas, quimiocinas, óxido nítrico (NO) e interações de moléculas de adesão. Estudos prévios investigaram as interações funcionais entre NO e CC-quimiocinas. Young e colaboradores (1999) mostraram que o número de eosinófilos no lavado broncoalveolar (LBA) de macacos desafiados está marcadamente aumentado 24 horas após o desafio, e que este aumento é acompanhado de altos níveis de NO no ar exalado e de eotaxina no LBA. Em pacientes com rinite, a eotaxina aumentou o número de eosinófilos no fluido do lavado nasal e também os níveis de NO nasal (Hanazawa et al....

Avaliação dos efeitos da quercetina e hecogenina sobre a atividade farmacológica e enzimática induzida por sPLA2 isoladas de venenos crotálicos e botrópicos; Evaluation of effects of quercetin and hecogenin on the pharmacological and enzymatic activities iduced by sPLA2

Camila Aparecida Cotrim
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 21/01/2011 PT
Relevância na Pesquisa
26.27%
Nas últimas décadas, o uso de compostos naturais como flavonóides e sapogeninas tem sido largamente difundidos na indústria farmacêutica devido suas atividades antiinflamatórias, prevenção de câncer e de doenças cardiovasculares. Neste trabalho, foi avaliado o efeito da quercetina (flavonóide) e hecogenina (sapogenina), sobre as atividades catalítica e farmacológicas de uma isoforma de fosfolipase A2 secretória (sPLA2) de Crotalus durissus terrificus em duas situações: pré-incubado e co-incubado. Na préincubação, a sPLA2 pura foi incubada com os compostos e os resultados indicam modificações estruturais na estrutura secundária como evidenciada pelas análise de dicroísmo circular. Os dois compostos foram capazes de diminuir a atividade enzimática, porém, somente a quercetina foi capaz de diminuir a mionecrose. Nenhum dos compostos apresentou efeito sobre a formação de edema. Na co-incubação, três concentrações diferentes dos compostos foram misturados com sPLA2 e imediatamente testados. A coincubação mostrou uma menor ação sobre atividade catalítica quando comparado com a préincubação, sugerindo a importância da incubação dos compostos com a proteína. Entretanto, a co-incubação mostrou melhor efeito sobre as atividades farmacológicas (edema e miotoxidade). Os resultados obtidos sugerem a existência de dois sítios farmacológicos distintos...

Características estruturais e funcionais de espermatozoides bovinos recuperados do epidídimo

Cunha, Andrielle Thainar Mendes
Fonte: Universidade de Brasília Publicador: Universidade de Brasília
Tipo: Dissertação
POR
Relevância na Pesquisa
26.2%
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, 2015.; A utilização de espermatozoides do epidídimo (EP) em técnicas de reprodução assistida tem um papel importante na multiplicação e armazenamento de material genético. Entretanto, melhor conhecimento sobre o comportamento fisiológico destes espermatozoides é necessário para otimizar a sua utilização. Objetivou-se avaliar a viabilidade, resistência e longevidade de EP de sete touros da raça Gir, durante e após a criopreservação, usando os espermatozoides do ejaculado (EJ) como controle. O ejaculado foi coletado através de eletroestimulação, posteriormente os animais foram castrados e os espermatozoides da cauda do epidídimo foram coletados pelo método de extravasamento. Primeiramente, verificou-se a resistência dos EJ e EP diante à criopreservação, as células foram avaliadas logo após a recuperação, após quatro horas de refrigeração e após o descongelamento. Em uma segundo etapa, foi avaliada a longevidade após a criopreservação. Foram utilizados três grupos de espermatozoides do EJ, do EP e um grupo em que EP foram incubados com plasma seminal (EPP). Após o descongelamento amostras dos três grupos foram incubadas por zero...

Evaluation and characterization of antioxidant and antigenotoxic properties of portuguese propolis

Cruz, Márcia; Ferreira, A. M.; Cunha, Ana; Aguiar, Cristina; Oliveira, Rui Pedro Soares de
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em /12/2011 ENG
Relevância na Pesquisa
26.22%
Propolis is a substance produced by bees (Apis mellifera L.), after harvesting exsudates of plant buds and barks, and subsequent mixing with the salivary enzyme β-glucosidase. Bees use propolis in their combs as protection, to repair damage, to build aseptic locals for the eggs of the queen, and also as a thermal insulator. The composition of propolis varies geographically, with the available flora, the time of collection and the race of the bees. Different groups of compounds can be found in propolis such as polyphenols, terpenoids, steroids and amino acids. Some of these compounds have been associated with diverse biological activities: antimicrobial, antioxidant, antigenotoxic, genotoxic and antimutagenic. Portuguese propolis has recently attracted the interest of researchers because of the opportunity for its economic valorization and the need to scientifically support the biological properties commonly assigned to samples of different origins. Thus, our objective relates to the analysis and study of Portuguese propolis, particularly in what concerns its chemical characterization and the evaluation of biological activities. A propolis ethanol extract (PEE) was made from a sample provided from an apiary (Côa) in Beira Alta and tested in different assays...

A modified assay for measuring thymocyte co-stimulatory activity

Dalmau,Sergio R.; Freitas,Claudia S.; Savino,Wilson
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/1993 EN
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36.03%
The observation that murine thymocytes increase their proliferation to interleukin 1 (IL-1) in the presence of phytohemagglutinin (PHA) when pre-incubated with interleukin 2 (IL-2) allowed the introduction of a modified assay for the measurement of IL-1 or the search of thymocyte-inducing proliferative activities in biological samples. Pre-incubation of thymocytes for 24 hr with 50 u/ml IL-2, followed by washings, elicited their maximal response to IL-1 in the usual lymphocyte activating factor (LAF) assay. This suggests that sequential events lead to thymocyte activation. The responsiveness is three to five fold greater than, and the total time of assay is the same as that of the LAF assay. Interestingly, pre-incubation with IL-2 renders thymocytes more sensitive than responsive to crude monocyte conditioned media. The use of the MTT colorimetric method for the assessment of thymocyte proliferation, and of the lectin jacalin as a co-mitogen are suggested as alternatives to be used in co-stimulatory assays.

Use of sex-sorted and unsorted frozen/thawed sperm and in vitro fertilization events in bovine oocytes derived from ultrasound-guided aspiration

Ruiz López,Salvador; Souza,José Camisão de; Zaraza González,Javier; De Ondiz Sánchez,Aitor; Romero-Aguirregomezcorta,Jon; Carvalho,Rafaela Rodrigues de; Rath,Detlef
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2013 EN
Relevância na Pesquisa
46.16%
The objective was to investigate the effects of sex-sorting on early fertilization events in ovum pick up (OPU) derived oocytes fertilized in vitro with frozen-thawed sperm at different co-incubation lengths. Eighty-four OPU sessions were carried out in 18 cyclic, dry and non-stimulated Holstein Friesian and German black pied cows. Ovum pick up oocytes were matured in vitro for 24 hours and fertilized with frozen-thawed sex sorted or unsorted sperm from the same ejaculate. Fertilization was achieved by two experimental protocols: 1) short gamete co-incubation length: 4, 8 and 12 hours; and 2) long gamete co-incubation length: 18 and 24 hours. After in vitro fertilization, ova were fixed and stained to identify early fertilization events. Sperm penetration, monospermy, pronuclear formation and syngamy did not differ, whether sexed or unsexed sperm was used. Overall, the findings demonstrate similar fertilizing potential between sex-sorted and unsorted sperm.

Examination of various cell culture techniques for co-incubation of virulent Treponema pallidum (Nichols I strain) under anaerobic conditions.

Sandok, P L; Knight, S T; Jenkin, H M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1976 EN
Relevância na Pesquisa
46.08%
Treponema pallidum (Nichols virulent) was incubated with and without cells in cell culture medium reduced to -275 mV Ecal, pH 7.3, under deoxygenated conditions. Five to ten percent of the treponemes attached to cells and remained motile for at least 120 h in cell-treponeme systems of co-incubation. Virulent treponemes could be detected after 120 to 144 h in the supernatant fluids of cell-treponeme co-incubation cultures and in cell-free tubes containing medium harvested from aerobically cultivated mammalian cells. Medium supplemented with ox serum ultrafiltrate, pyruvate, and sodium thioglycolate and gas mixtures containing H2 and CO2 enhanced treponemal survival. Increases in treponemal numbers were observed using dark-field microscopy but were not substantiated using the rabbit lesion test. Continuous passage of the treponeme was not achieved in vitro.

Non-specific effects of avian retrovirus co-incubation on lymphocyte function: abrogation of antigen- and mitogen-induced proliferative responsiveness.

Israel, E; Yu, M; Wainberg, M A
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1979 EN
Relevância na Pesquisa
46.03%
Peripheral blood lymphocytes from chickens bearing tumours induced by avian retroviruses can be stimulated to divide by group-specific antigens present in supernatant fluids of avian retrovirus-infected but not normal chicken embryo fibroblast (CEF) cells. Centrifugation studies revealed that the relevant antigenic activity is non-virion in nature. Indeed, the presence of avian retrovirus particles was found to be inhibitory to the capacity of sensitized lymphocytes to be stimulated in this antigen-driven blastogenesis assay. Similar results were obtained in lymphocyte mitogenesis experiments in which any of peripheral chicken lymphocytes or mouse splenic, lymph node or thymic lymphocytes were co-incubated with either concanavalin A or phytohaemagglutinin in the presence of numerous types of virus particles. This inhibitory effect was not due to infection of lymphocytes by the viruses tested, and was obtained in the case of lymphocyte-virus combinations for which the cells lacked the surface receptors required for viral entry. Virus could be added to lymphocyte cultures as late as 26 h after co-incubation with mitogen, and still inhibit the usual mitogenic response. In addition, co-addition of virus to lymphocytes in the presence of concanavalin A was found to block the capping of ligand-bound receptors which normally ensues. Pre-added virus did not...

Co-incubation of pig islet cells with spleen cells from non-obese diabetic mice causes decreased insulin release by non-T-cell- and T-cell-mediated mechanisms

You, S; Rivereau, A-S; Gouin, E; Saï, P
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Publicado em /07/2001 EN
Relevância na Pesquisa
46.24%
In vitro studies were conducted in the non-obese diabetic (NOD) mouse, prone to Type 1 autoimmune diabetes, to investigate the mechanisms involved in cell-mediated rejection of pig islet xenografts. Our previous work concerning the mechanisms of proliferation of xenogeneic lymphocytes to pig islet cells (PIC) was not indicative of PIC impairment. Consequently, a test was developed based on perifusion analysis of the alteration of basal and stimulated insulin release from adult PIC incubated with mouse splenocytes or subsets. Compared with PIC incubation alone or with syngeneic pig splenocytes, co-incubation with mouse whole spleen cells resulted in a decrease of basal and stimulated insulin release (P < 0·001). Two components of this alteration were detected separately: PIC impairment was decreased (P < 0·01) after removal of plastic-adherent cells from spleen cells, but maintained (P < 0·01) when plastic-adherent cells alone were co-incubated with PIC. The increase of murine interleukin-1β when mouse plastic-adherent spleen cells were cultured with PIC (P < 0·04) was indicative of macrophage activation. Soluble factors produced during co-incubation of mouse splenocytes or plastic-adherent cells with PIC were involved in the impairment process...

Nucleobindin Co-Localizes and Associates with Cyclooxygenase (COX)-2 in Human Neutrophils

Leclerc, Patrick; Biarc, Jordane; St-Onge, Mireille; Gilbert, Caroline; Dussault, Andrée-Anne; Laflamme, Cynthia; Pouliot, Marc
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 21/05/2008 EN
Relevância na Pesquisa
35.79%
The inducible cyclooxygenase isoform (COX-2) is associated with inflammation, tumorigenesis, as well as with physiological events. Despite efforts deployed in order to understand the biology of this multi-faceted enzyme, much remains to be understood. Nucleobindin (Nuc), a ubiquitous Ca2+-binding protein, possesses a putative COX-binding domain. In this study, we investigated its expression and subcellular localization in human neutrophils, its affinity for COX-2 as well as its possible impact on PGE2 biosynthesis. Complementary subcellular localization approaches including nitrogen cavitation coupled to Percoll fractionation, immunofluorescence, confocal and electron microscopy collectively placed Nuc, COX-2, and all of the main enzymes involved in prostanoid synthesis, in the Golgi apparatus and endoplasmic reticulum of human neutrophils. Immunoprecipitation experiments indicated a high affinity between Nuc and COX-2. Addition of human recombinant (hr) Nuc to purified hrCOX-2 dose-dependently caused an increase in PGE2 biosynthesis in response to arachidonic acid. Co-incubation of Nuc with COX-2-expressing neutrophil lysates also increased their capacity to produce PGE2. Moreover, neutrophil transfection with hrNuc specifically enhanced PGE2 biosynthesis. Together...

Protein delivery into live cells by incubation with an endosomolytic agent

Erazo-Oliveras, Alfredo; Najjar, Kristina; Dayani, Laila; Wang, Ting-Yi; Johnson, Gregory A.; Pellois, Jean-Philippe
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
35.84%
We report on how a dimer of the cell-penetrating peptide TAT, dfTAT, penetrates live cells by escaping from endosomes with a particularly high efficiency. By mediating endosomal leakage, dfTAT also delivers proteins into cultured cells after a simple co-incubation procedure. Cytosolic delivery is achieved in most cells in a culture and only a relatively small amount of material remains trapped inside endosomes. Delivery does not require binding interactions between dfTAT and a protein, multiple molecules can be delivered at once, and delivery can be repeated. Remarkably, dfTAT-mediated delivery does not noticeably impact cell viability, proliferation, or gene expression. This new delivery strategy should be extremely useful for cell-based assays, cellular imaging applications, and the ex vivo manipulation of cells.

Histone deacetylase inhibitor-temozolomide co-treatment inhibits melanoma growth through suppression of Chemokine (C-C motif) ligand 2-driven signals

Gatti, Laura; Sevko, Alexandra; Cesare, Michelandrea De; Arrighetti, Noemi; Manenti, Giacomo; Ciusani, Emilio; Verderio, Paolo; Ciniselli, Chiara M.; Cominetti, Denis; Carenini, Nives; Corna, Elisabetta; Zaffaroni, Nadia; Rodolfo, Monica; Rivoltini, Licia
Fonte: Impact Journals LLC Publicador: Impact Journals LLC
Tipo: Artigo de Revista Científica
Publicado em 06/06/2014 EN
Relevância na Pesquisa
35.79%
Target-specific agents used in melanoma are not curative, and chemokines are being implicated in drug-resistance to target-specific agents. Thus, the use of conventional agents in rationale combinations may result in optimization of therapy. Because histone deacetylases participate in tumor development and progression, the combination of the pan-inhibitor SAHA and temozolomide might provide a therapeutic advantage. Here, we show synergism between the two drugs in mutant BRAF cell lines, in association with decreased phosphorylation of cell survival proteins (e.g., C-Jun-N-terminal-kinase, JNK). In the spontaneous ret transgenic mouse melanoma model, combination therapy produced a significant disease onset delay and down-regulation of Chemokine (C-C motif) ligand 2 (CCL2), JNK, and of Myeloid-derived suppressor cell recruitment. Co-incubation with a CCL2-blocking-antibody enhanced in vitro cell sensitivity to temozolomide. Conversely, recombinant CCL2 activated JNK in human tumor melanoma cells. In keeping with these results, the combination of a JNK-inhibitor with temozolomide was synergistic. By showing that down-regulation of CCL2-driven signals by SAHA and temozolomide via JNK contributes to reduce melanoma growth, we provide a rationale for the therapeutic advantage of the drug combination. This combination strategy may be effective because of interference both with tumor cell and tumor microenvironment.

Conserva??o do s?men e liquefa??o do co?gulo seminal de macaco-prego (Cebus apella) em ?gua de coco em p? (ACP-118?), em diferentes temperaturas

OLIVEIRA, Karol Guimar?es; CASTRO, Paulo Henrique Gomes de; MUNIZ, Jos? Augusto Pereira Carneiro; DOMINGUES, Sheyla Farhayldes Souza
Fonte: Universidade Federal do Pará Publicador: Universidade Federal do Pará
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
36.06%
O objetivo do estudo foi avaliar a ?gua de coco em p? (ACP) na conserva??o do s?men e liquefa??o do co?gulo seminal de Cebus apella. O s?men de seis machos adultos foi coletado por eletroejacula??o (EEJ), dilu?do em solu??o ? base de ACP-118? e submetido ? incuba??o em banho-maria a 33, 35 e 37?C, por 24 horas. Avaliou-se a integridade esperm?tica por meio da colora??o eosina-nigrosina a cada uma hora durante as seis horas iniciais e ap?s 24 horas de incuba??o. Os volumes m?dios e as concentra??es esperm?ticas das fra??es coagulada e l?quida foram de 0,20?0,02 e 0,20?0,10mL; 1,1?0,3x108 e 1,3?0,9x107 espermatozoides mL-1, respectivamente. Somente em uma amostra da fra??o l?quida foram verificados espermatozoides com motilidade (20%) e vigor (4), perdurando por 40 minutos. A maior parte do co?gulo liquefez em ACP-118? ap?s 12 horas de incuba??o. O melhor tratamento observado foi sob 33?C, por manter at? 47?12,8% de espermatozoides vivos ap?s 24 horas. Conclui-se que o diluente ? base de ACP ? eficiente na liquefa??o do co?gulo seminal e na manuten??o da integridade esperm?tica at? 24 horas ap?s a EEJ, nas temperaturas de 33, 35 e 37?C.; ABSTRACT: The aim of this study was to evaluate the powdered coconut water (PCW) in the semen conservation and seminal clot liquefaction. The semen of six adult male Cebus apella was collected by electroejaculation (EEJ)...

Indigenous plant based coagulants/disinfectants and sand filter media for surface water treatment in Bamenda, Cameroon

Yongabi, K.; Lewis, D.; Harris, P.
Fonte: Academic Journals Publicador: Academic Journals
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
Relevância na Pesquisa
26.18%
The antioxidant potency of acetone, chloroform and methanol extracts of Argemone mexicana was investigated by employing in vitro systems like nitroblue tetrazolium (NBT) and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay whereas antimutagenic activity was determined by Maron and Ames assay usingSalmonella typhimurium TA100 tester strain against sodium azide. In this study, dried fruits of A. mexicana were extracted with different solvents by maceration method in order of increasing polarity. It was observed that, acetone extracts were comparatively more effective than the other extracts in both the assays. The maximum inhibitory activities noticed were 79.0 and 71.0% in NBT and DPPH assay, respectively, at the maximum concentration tested. The inhibitory potential was compared with standard antioxidant (L-ascorbic acid). The IC50 value of the acetone extract of the fruit of A. mexicana was more than that of L-ascorbic acid showing the maximum inhibitory effect. Among the different extracts, the antimutagenic effect of methanol extract was found to be more followed by acetone and chloroform extracts. The methanol extract showed maximum inhibition of 80.5% at doses of 1.00×103 in co-incubation and 0.10×103 µg/ml in pre-incubation modes of the experiments...

Improved function of rat islets upon co-microencapsulation with Sertoli's cells in alginate/poly-L-ornithine

Luca, Giovanni; Calafiore, Riccardo; Basta, Giuseppe; Ricci, Maurizio; Calvitti, Mario; Neri, Luca; Nastruzzi, Claudio; Becchetti, Ennio; Capitani, Silvano; Brunetti, Paolo; Rossi, Carlo
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
Publicado em 26/08/2001 EN
Relevância na Pesquisa
36.06%
The purpose of this study was to assess whether Sertolis cells would improve functional performance of homologous pancreatic islets within microcapsules. Purified rat Sertoli's cells were co-enveloped with islets in microcapsules that had been fabricated with alginic acid and poly-L-ornithine Confocal laser microscopy was used to determine any mitogenic effects of Sertoli's cells on islets ß-cells. Insulin secretion from islets, with or without Sertoli's cells, was examined and grafts of Sertoli's cells with islets in microcapsules into diabetic mice were carried out. Co-incubation of Sertoli's cells with islets resulted in a significant increase in the islet ß-cell mitotic rate, which was coupled with significantly higher insulin release under glucose stimulation, as compared to controls. Grafts of co-microencapsulated Sertoli's cells with islets resulted in prolongation of the achieved normoglycemia in the animals receiving Sertoli's cells with islets as compared to controls that received islets only. Sertoli's cells do promote mitogenic activities upon in vitro co-incubation with islets, whose in vitro functional and in vivo post-transplant consequences were evident. Sertoli's cells could, therefore, be comicroencapsulated with islets for transplantation in diabetic recipients.

Patients with inflammatory bowel disease (IBD) reveal increased induction capacity of intracellular interferon-gamma (IFN-γ) in peripheral CD8+ lymphocytes co-cultured with intestinal epithelial cells

Bisping, G; Lügering, N; Lütke-Brintrup, S; Pauels, H -G; Schürmann, G; Domschke, W; Kucharzik, T
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Publicado em /01/2001 EN
Relevância na Pesquisa
36.14%
Intestinal epithelial cells seem to play a key role during IBD. The network of cellular interactions between epithelial cells and lamina propria mononuclear cells is still incompletely understood. In the following co-culture model we investigated the influence of intestinal epithelial cells on cytokine expression of T cytotoxic and T helper cells from patients with IBD and healthy controls. Peripheral blood mononuclear cells (PBMC) were purified by a Ficoll–Hypaque gradient followed by co-incubation with epithelial cells in multiwell cell culture insert plates in direct contact as well as separated by transwell filters. We used Caco-2 cells as well as freshly isolated colonic epithelia obtained from surgical specimens. Three-colour immunofluorescence flow cytometry was performed after collection, stimulation and staining of PBMC with anti-CD4, anti-CD8, anti-IFN-γ and anti-IL-4. Patients with IBD (Crohn's disease (CD), n = 12; ulcerative colitis (UC), n = 16) and healthy controls (n = 10) were included in the study. After 24 h of co-incubation with Caco-2 cells we found a significant increase of IFN-γ-producing CD8+ lymphocytes in patients with IBD. In contrast, healthy controls did not respond to the epithelial stimulus. No significant differences could be found between CD and UC or active and inactive disease. A significant increase of IFN-γ+/CD8+ lymphocytes in patients with UC was also seen after direct co-incubation with primary cultures of colonic crypt cells. The observed epithelial–lymphocyte interaction seems to be MHC I-restricted. No significant epithelial cell-mediated effects on cytokine expression were detected in the PBMC CD4+ subsets. Patients with IBD—even in an inactive state of disease—exert an increased capacity for IFN-γ induction in CD8+ lymphocytes mediated by intestinal epithelial cells. This mechanism may be important during chronic intestinal inflammation...

In vitro penetration of swine oocytes by homologous spermatozoa: Distinct systems for gamete’s co-incubation and oocyte’s cryopreservation

Macedo Júnior, Milton C.; Lucia Júnior, Thomaz; Rambo, Gissele; Ferreira Filho, E. B.; Rosa, A. P.; Fabiane, C.; Cabral, M.; Deschamps, João Carlos
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
EN_US
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In vitro penetration (IVP) of swine oocytes by homologous spermatozoa was evaluated in two experiments using four boars as semen donors. In experiment 1, the IVP rate and the number of penetrating spermatozoa (PSP) were compared using three co-incubation systems for vitrified oocytes and fresh sperm: (1) 35mL petri dishes in a CO2 incubator, (2) 35mL petri dishes in bags (submarine system) and (3) glass flasks partially submerged in water bath with the same gas mixture used for the bag system. Mean PSPwas 8.2±10.1 and the IVP ratewas 90.5%. The PSP differed across all systems (P = 0.0006): 15.5±0.5 for flasks, 6.3±0.4 for CO2, and 3.9±0.4 for bags. The IVP rate for flasks (95.0%) was greater (P = 0.01) than for CO2 and bags (90.8% and 85.0%, respectively), but it did not differ between flasks and CO2 for three boars (P > 0.05). In experiment 2, co-incubation was done as described for glass flasks in experiment 1. The IVP rate and PSP were compared for cryopreserved oocytes: either vitrified in open pulled straws (OPS), or frozen in cryotubes. Mean PSP was 5.4±6.5 and IVP ratewas 89.6%. Both PSP and IVP ratewere greater (P < 0.0001) for oocytes frozen in cryotubes (7.0±0.3% and 95.8%, respectively) than those frozen in OPS (3.7±0.3% and 83.4%...

Effects of Aeromonas caviae co-cultured in mouse small intestine

Longa-Briceño,Aurora; Peña-Contreras,Zulma; Dávila-Vera,Delsy; Mendoza-Briceño,Rosa Virginia; Palacios-Prü,Ernesto
Fonte: ASOCIACIÓN INTERCIENCIA Publicador: ASOCIACIÓN INTERCIENCIA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2006 EN
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The ultrastructural aspects generated by the interaction between two strains of Aeromonas caviae with mouse intestinal mucosa are described. One of the strains was isolated from an asymptomatic patient and the other one from a patient with diarrhea. Both strains were separately inoculated in closed cylinders of mouse small intestine and the whole preparations were incubated in Eagle’s culture medium. The intestinal cylinders were divided into two groups, one was incubated for 24h and the other for 48h. Samples of the co-cultures were processed for analysis using high resolution light microscopy and transmission electron microscopy. The strain isolated from the asymptomatic patient showed variable alterations in the intestinal mucosa, according to the different periods of incubation, whereas the one obtained from the patient with diarrhea always produced severe enteropathogenic effects