Influência do tipo de parto na hematologia do cordão umbilical de cães

O sangue do cordão umbilical humano tem sido crescentemente utilizado como fonte de células-tronco. Os modelos experimentais de células-tronco da medula óssea, em cães, têm propiciado informações importantes para transplantes medulares em humanos. Vários trabalhos citam a influência do tipo de parto nas características do sangue do cordão umbilical (SCU) humano. Entretanto, não existem relatos sobre a colheita do sangue do cordão umbilical de cães. O objetivo deste ensaio é avaliar a influência do tipo de parto na hematologia do cordão umbilical de cães. No presente protocolo experimental, foram estudados 54 fetos de cães, ao final da vida intra-uterina, provenientes de parto normal (n=24) e cesariana (n=30). A colheita de sangue do cordão umbilical foi realizada com seringa de cinco mL contendo solução anticoagulante EDTA (1mg/1mL sangue). em seguida, a contagem global de hemácias, leucócitos, plaquetas, a determinação da concentração de hemoglobina, taxa de hematócrito, os índices eritrocitários foram realizados no contador automático de células. A contagem diferencial de leucócitos foi determinada em esfregaços de SCU corados com May-Grunwald-Giemsa (MGG). Com relação ao eritrograma e ao plaquetograma, não houve diferença significativa entre as amostras obtidas em cesarianas e partos normais. Os valores do leucograma do SCU colhido em partos normais foram superiores àqueles obtidos em cesarianas (P<0,05). Portanto, o tipo de parto influencia os valores hematológicos do cordão umbilical de cães.

Cardiac function in dogs with chronic Chagas cardiomyopathy undergoing autologous stem cell transplantation into the coronary arteries

This study assessed the effects of a single intracoronary injection of autologous stem cells on the cardiac function of dogs with Chagas cardiomyopathy. Bone-marrow-derived stem cells were delivered into the right and left coronary arteries of 5 mature dogs with mildly compromised cardiac function due to chronic Chagas cardiomyopathy. Blood pressure and electrocardiographic and echocardiographic parameters were recorded at monthly intervals for 6 mo in the 3 dogs that survived. Although no changes were observed in the electrocardiogram and blood pressure, there was a significant increase in peak velocity of aortic flow 3 mo after stem cell transplantation. Pre-ejection period, isovolumic relaxation time, and the Tei index of myocardial performance were reduced significantly 4 mo after the procedure. All significant changes persisted to the end of the study. The results suggest that the transplantation of autologous bone-marrow-derived stem cells into the coronary arteries of dogs with Chagas cardiomyopathy may have a beneficial effect but the small number of dogs studied was a limitation.

Viabilidade celular da fração mononuclear da medula óssea e fração vascular estromal do tecido adiposo de equinos após o processo de congelamento e descongelamento

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Molecular and serological detection of Leishmania spp. in captive wild animals from Ilha Solteira, SP, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Antimutagenic effect of Lentinula edodes (BERK.) Pegler mushroom and possible variation among lineages

This study was performed to evaluate the efficiency of four different lineages (95/01, L1, 96/22 and JABK) of Lentinula edodes (BERK.) Pegler mushroom (shiitake) for inhibiting the N-ethyl-N-nitrosourea (ENU) clastogenicity in vivo. Male Swiss mice (10 animals/group) were treated during 15 consecutive days with dried mushroom added to basal diet under three different concentrations (1, 5 and 10%). At day 15, mice were intraperitoneally injected with ENU (50 mg/kg body weight) and sacrificed 24 h later for evaluation of micronucleated bone marrow polychromatic erythrocytes (MNPCE). Negative and positive controls (10 animals each), receiving basal diet and saline or ENU ip injection, respectively, were also evaluated. Results showed that pretreatments with diets containing the lineages 95/01, L1 and 96/22 reduce the frequencies of MNPCE induced by ENU. The absence of an antimutagenic activity for the lineage JABK might be related to intrinsic differences among the lineages such as biochemical composition. Taken together, our data show that the differences in protective activities of the mushrooms need to be clarified in further studies and the mechanisms for such activities need to be investigated. (C) 2003 Elsevier B.V. Ltd. All rights reserved.

Dendritic cell are able to differentially recognize Sporothrix schenckii antigens and promote Th1/Th17 response in vitro

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mutagenicity and genotoxicity of isatin in mammalian cells in vivo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Acute, subacute toxicity and genotoxic effect of a hydroethanolic extract of the cashew (Anacardium occidentale L.)

Anacardium occidentale L. (Anacardiaceae), popularly known as cajueiro is a native plant to Brazil, and largely used in popular medicine to treat ulcers, hypertension and diarrhea. In the present study, acute, 30-day subacute toxicity and genotoxicity assays were carried out. The crude extract did not produce toxic symptoms in rats in doses up to 2000 mg/kg. Based on biochemical analyses of renal and hepato-biliary functions, such as the level of urea, creatinine, transaminases and alkaline phosphatase, we determined that the extract is generally tolerated by rats. This was also confirmed by hematological and histopathological exams. Genotoxicity was accessed by the Ames test in Salmonella typhimurium strains TA97, TA98, TA 100, TA 102 and by the bone marrow micronucleus test in mice. The extract was shown to induce frameshift, base pair substitution and damage to the chromosomes. However, this effect was less deleterious than the clastogenic effect of ciclophosphamide. (c) 2006 Elsevier B.V.. All rights reserved.

Comparative effects of acute and subacute lycopene administration on chromosomal aberrations induced by cisplatin in male rats

Lycopene is a natural carotenoid, free radical scavenger, and presents protective effects by inhibiting oxidative DNA damage. The objective of the current study was to investigate the cytogenetic effects of a single acute and four daily gavage administrations of lycopene, and to examine possible protective effects on chromosomal damage induced by the antitumor drug cisplatin (cDDP) in rat bone marrow cells. The animals were divided into treatment groups, with three lycopene doses in the acute treatment (2, 4, and 6 mg/kg b.w.), three lycopene doses in the subacute treatment (0.5, 1.0, and 1.5 mg/kg b.w.) with and without cDDP (5 mg/kg b.w. i.p.), and respective controls. The results indicated that lycopene is neither cytotoxic nor clastogenic when compared with the negative controls (P > 0.01). cDDP-treated animals submitted to acute and subacute treatments with different lycopene doses showed a significant reduction (p < 0.01) in the number of abnormal metaphases when compared with the animals treated only with cDDP. The protective effects of lycopene on cDDP-induced chromosomal damage may be attributed to its antioxidant activity. These results suggest that this carotenoid may prove useful in reducing some of the toxic effects associated with certain classes of chemotherapeutic agents. (c) 2006 Elsevier Ltd. All rights reserved.

Evaluation of the genotoxic potential of the isocoumarin paepalantine in in vivo and in vitro mammalian systems

Paepalantine is an isocoumarin isolated from Paepalanthus vellozioides which showed antimicrobial activity in in vitro experiments. In the present study, paepalantine was tested for possible clastogenic and cytotoxic action. Cultures from different individuals were treated with paepalantine at concentrations of 20, 40 and 80 mu g/ml. The effect of isocoumarin was also tested in an in vivo assay using Wistar rat bone marrow cells. Paepalantine was administered intraperitoneally at concentrations of 6.25, 12.5 and 25 mg/kg body weight. Under these conditions paepalantine did not have a clastogenic effect, but was significantly cytotoxic in the in vitro and in vivo mammalian cell systems tested in the present work. (C) 1999 Elsevier B.V. Ireland Ltd. All rights reserved.

Adesão de células mesenquimais da medula óssea de camundongos e do ligamento periodontal de ratos a diferentes superfícies de titânio: estudo comparativo in vitro

The present experiment used cell culture to analyze the adhesion capacity of mouse mesenchymal bone marrow cells and rat periodontal ligament to different titanium surfaces. Grade II ASTM F86 titanium discs 15mm in diameter and 1.5mm thick were used and received 2 distinct surface treatments (polished and cathodic cage plasma nitriding). The cells were isolated from the mouse bone marrow and rat periodontal ligament and cultured in α-MEM basic culture medium containing antibiotics and supplemented with 10% FBS and 5% CO2, for 72 hours at 37ºC in a humidified atmosphere. Subculture cells were cultured in a 24-well plate with a density of 1 x 104 cells per well. The titanium discs were distributed in accordance with the groups, including positive controls without titanium discs. After a 24-hour culture, the cells were counted in a Neubauer chamber. The results show that both the mouse mesenchymal bone marrow cells and rat periodontal ligament cells had better adhesion to the control surface. The number of bone marrow cells adhered to the polished Ti surface was not statistically significant when compared to the same type of cell adhered to the Ti surface treated by cathodic cage plasma nitriding. However a significant difference was found between the control and polished Ti groups. In relation to periodontal ligament cell adhesion, a significant difference was only found between the control and plasma-treated Ti surfaces. When comparing equal surfaces with different cells, no statistically significant difference was observed. We can therefore conclude that titanium is a good material for mesenchymal cell adhesion and that different material surface treatments can influence this process

Plasticidade de células tronco mesenquimais de medula óssea de ratos na presença de meio condicionado do nervo facial e do fator de crescimento fibroblástico 2

A number of evidences show the influence of the growth of injured nerve fibers in Peripheral Nervous System (PNS) as well as potential implant stem cells (SCs) to make it more suitable for nerve regeneration medium. In this perspective, this study aimed to evaluate the plasticity of mesenchymal stem cells from bone marrow of mice in the presence of culture medium conditioned with facial nerve explants (D-10) and fibroblast growth factor-2 (FGF-2). In this perspective, the cells were cultivated only with DMEM (group 1), only with D-10(group 2), only with FGF-2(group 3) or with D-10 and FGF-2(group 4). The growth and morphology were assessed over 72 hours. Quantitative phenotypic analysis was taken from the immunocytochemistry for GFAP, OX-42, MAP-2, β-tubulin III, NeuN and NF-200 on the fourth day of cultivation. Cells cultured with conditioned medium alone or combined with FGF-2 showed distinct morphological features similar apparent at certain times with neurons and glial cells and a significant proliferative activity in groups 2 and 4 throughout the days. Cells cultived only with conditioned medium acquired a glial phenotype. Cells cultured with FGF-2 and conditioned medium expressed GFAP, OX-42, MAP-2, β-tubulin III, NeuN and NF-200. On average, area and perimeter fo the group of cells positive for GFAP and the área of the cells immunostained for OX-42 were higher than those of the group 4. This study enabled the plasticity of mesenchymal cells (MCs) in neuronal and glial nineage and opened prospects for the search with cell therapy and transdifferentiation

Estudo da descelularização tecidual na produção de arcabouços biológicos para enxertos

The regeneration of bone defects with loss of substance remains as a therapeutic challenge in the medical field. There are basically four types of grafts: autologous, allogenic, xenogenic and isogenic. It is a consensus that autologous bone is the most suitable material for this purpose, but there are limitations to its use, especially the insufficient amount in the donor. Surveys show that the components of the extracellular matrix (ECM) are generally conserved between different species and are well tolerated even in xenogenic recipient. Thus, several studies have been conducted in the search for a replacement for autogenous bone scaffold using the technique of decellularization. To obtain these scaffolds, tissue must undergo a process of cell removal that causes minimal adverse effects on the composition, biological activity and mechanical integrity of the remaining extracellular matrix. There is not, however, a conformity among researchers about the best protocol for decellularization, since each of these treatments interfere differently in biochemical composition, ultrastructure and mechanical properties of the extracellular matrix, affecting the type of immune response to the material. Further down the arsenal of research involving decellularization bone tissue represents another obstacle to the arrival of a consensus protocol. The present study aimed to evaluate the influence of decellularization methods in the production of biological scaffolds from skeletal organs of mice, for their use for grafting. This was a laboratory study, sequenced in two distinct stages. In the first phase 12 mice hemi-calvariae were evaluated, divided into three groups (n = 4) and submitted to three different decellularization protocols (SDS [group I], trypsin [Group II], Triton X-100 [Group III]). We tried to identify the one that promotes most efficient cell removal, simultaneously to the best structural preservation of the bone extracellular matrix. Therefore, we performed quantitative analysis of the number of remaining cells and descriptive analysis of the scaffolds, made possible by microscopy. In the second stage, a study was conducted to evaluate the in vitro adhesion of mice bone marrow mesenchymal cells, cultured on these scaffolds, previously decellularized. Through manual counting of cells on scaffolds there was a complete cell removal in Group II, Group I showed a practically complete cell removal, and Group III displayed cell remains. The findings allowed us to observe a significant difference only between Groups II and III (p = 0.042). Better maintenance of the collagen structure was obtained with Triton X-100, whereas the decellularization with Trypsin was responsible for the major structural changes in the scaffolds. After culture, the adhesion of mesenchymal cells was only observed in specimens deccelularized with Trypsin. Due to the potential for total removal of cells and the ability to allow adherence of these, the protocol based on the use of Trypsin (Group II) was considered the most suitable for use in future experiments involving bone grafting decellularized scaffolds

Genotoxicity assessment of Garcinia achachairu Rusby (Clusiaceae) extract in mammalian cells in vivo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

In vivo genotoxicity assessment of nerolidol

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)