Cetuximab has an inhibitory effect on cell motility in SCC-4 oral squamous cell carcinoma cell line.

Cetuximab is a chimeric monoclonal antibody that acts as a competitive antagonist, by binding to EGFR. This cell signalling pathways regulates tumor progression. The oral squamous cell carcinoma undergoes to regional spreading and distant metastasis. This study aimed to evaluate the effect of treatment with Cetuximab on cell migration and invasion in OSCC cells, by using the SCC-4 cell line. Cell migration and cell invasion assay were performed and actin cytoskeleton of control and treated with Cetuximab cells were evaluated. Differences were considered significant when p<0.05.Cetuximab inhibited the migration of SCC-4 cells at three concentrations: 1 µg/mL, 50 µg/mL and 100 µg/mL (p<0.0001) in a dose-dependent manner. The number of SCC-4 treated cells with 1 µg/mL that migrated through the membrane was statistically different from 50 µg/mL (p<0.001) and 100 µg/mL (p<0.0001), and between 50 µg/mL and 100 µg/mL (p<0.01). Cetuximab 50 µg/mL inhibited cell invasion through the MatrigelTM compared with SCC-4 control cells (p<0.01). Cetuximab 50 µg/mL affected the organization of the actin cytoskeleton. Cetuximab has an inhibitory effect on actin cytoskeleton organization, cell migration and invasion, suggesting that Cetuximab treatment can be important to avoid oral squamous cell carcinoma metastasis.

Genotyping of Toxoplasma gondii Directly from Human and Animal Biological Samples: From Partial Genotypes to a New Genotype.

Genotyping of Toxoplasma gondii is traditionally performed using DNA obtained from tachyzoites after isolation by bioassay in mice. In this study, genotyping of T. gondii was performed by multiplex nested polymerase chain reaction restriction fragment length polymorphism (Mn-PCR-RFLP) in DNA obtained from the lungs of experimentally infected mice, the hearts of naturally infected free-range chickens, and human blood samples of newborns with congenital toxoplasmosis. The efficiency of Mn-PCR varied according to the marker. We obtained complete genotypes of all of the mice lung samples. In chickens, total or partial genotyping was performed on all of the 15 samples. Two complete genotypes were obtained, including one identified for the first time, and another previously described in different hosts including dogs, cats, and humans. In blood from infants, partial genotypes were obtained in 8 of the 12 samples. Mouse bioassay is the most efficient method to obtain DNA from T. gondii , but direct tissue genotyping enhances the likelihood of obtaining molecular information on T. gondii and is an effective tool as a complement to isolation in mice. In this study, we genotyped Toxoplasma gondii directly from human (blood samples of newborns with congenital toxoplasmosis) and free-range chickens (hearts) by Mn-PCR-RFLP. We present partial and complete genotypes and provide technical and scientific information about T. gondii genotyping methods.

Pitfall Traps and Mini-Winkler Extractor as Complementary Methods to Sample Soil Coleoptera.

We compared abundance, species richness, and capture efficiency with pitfall traps and mini-Winkler extractors to examine their use as complementary methods for sampling soil Coleoptera during dry (2010) and high water seasons (2011) in three areas, including inundated and non-inundated regions, in the Pantanal of Poconé, Mato Grosso, Brazil. We paired treatments with two 10 × 10 m plots in inundated and non-inundated locations that were repeated three times in each location for a total of 18 plots. In each plot, we used nine pitfall traps and collected 2 m(2) of leaf litter and surface soil samples with mini-Winkler extractors. We collected a total of 4260 adult beetles comprising 36 families, 113 genera, and 505 species. Most were caught in pitfalls (69%) and the remainder in the mini-Winkler extractors (31%). Each method provided distinct information about the beetle community: 252 species were captured only in pitfall traps, 147 using only the mini-Winkler extractors, and these methods shared another 106 species. Pitfall and mini-Winkler contribute in different ways for the sampling of the soil beetle community, and so they should be considered complementary for a more thorough assessment of community diversity.

New gentotypes of Toxoplasma gondii obtained from farm animals in Northeast Brazil.

Genotyping of Toxoplasma gondii in different regions of Brazil has shown high diversity and high frequency of virulent genotypes among Brazilian animals. The aim of the study was to characterize samples of T. gondii isolates obtained from naturally infected sheep, goats, pigs and free-range chickens slaughtered for human consumption in Rio Grande do Norte, Northeast Brazil. Nineteen T. gondii samples (isolated from 1 goat, 5 pigs and 13 free-range chickens) were genotyped. Six different genotypes were identified, including two novel genotypes. The archetype genotypes, i.e., types I, II and III, were not found. In mice, seventeen isolates (89.5%) were classified as virulent, and only two (10.5%) were classified as avirulent. This study displays the genotypic variability of the parasite in Northeast Brazil.

Seroprevalence and risk factors of caprine toxoplasmosis in Minas Gerais, Brazil.

The objective of this work was to carry out a study on caprine toxoplasmosis in the state of Minas Gerais, Brazil. To determine the prevalence of toxoplasmosis in goats in Minas Gerais, 767 sera from goats were tested by ELISA (enzyme-linked immunosorbent assay) and IFAT (indirect fluorescence antibody test). The prevalence of antibodies to Toxoplasma gondii was 43.0% and 46.0% by ELISA and IFAT, respectively. It was observed that 26.8% of the goats show low-avidity IgG to T. gondii. These results suggest the presence of animals in recent phase of toxoplasmosis in Minas Gerais. The risk factors for toxoplasmosis in goats were: age over 36 months (OR=1.21; IC 95% 1.02-1.44), use of pen (OR=1.83; IC 95%1.01-3.31) and pure breed animals (OR=2.49; IC 95% 1.11-5.59).

[Standardization of a double antibody radioimmunoassay technic for the determination of growth hormone in the rat plasma and pituitary]. / Padronizacão da técnica de radioimunoensaio com duplo anticorpo para determinacão do hormonio de crescimento en plasma e hipófise de rato.

Bioassay techniques are not sufficiently sensitive to measure plasma growth hormone nor are they entirely specific for the growth hormone molecule. All these requirements are fulfilled by the radioimmunoassay technique. Successful performance of the GH radioimmunoassay technique is dependent upon the good quality of the protein reagents (antibodies) used and the great care taken in handling both the reagents and the labelled hormone. The described method is based on displacement of the radioiodinated (125I) hormone bound to the first antibody (Ab1 = monkey serum anti-rat's GH) by the sample hormone. The hormone Ab1 complex is precipitated by the Ab2 (rabbit serum anti-monkey gammaglobulin). The radiation of the insoluble precipitate is then counted and the hormone quantitated through a standard curve. In the present paper we dealt with Ab2 obtention, hormone radiolabelling, and the purification of the radioiodinated hormone. The accomplished specific tests showed values of 70% for the hormonal radioiodination efficiency, with 88.7% of the processed hormone being recovered in the pure state. The highest precipitability value of the system was 84.6% whereas using optimal dilutions of the labelled-hormone (1:250) and Ab1 (1:4x10(4)) this value achieved 26.9%. These results are very much in agreement with those notified in the literature. Applying the present protocol to the analysis of plasma-and anterior-pituitary-gland-GH content from young-adult Wistar male rats kept on normal feeding schedule and rest conditions the values obtained were 82 +/- 28 ng/ml (plasma) and 63 +/- 15 ng/mg (pituitary), respectively.

The supracloacal chromolipoid body of the black vulture (Coragyps atratus): anatomical, histological and histochemical considerations.

During histological and physiological investigations of black vultures (Coragyps atratus) dissection revealed the presence of an "organ", the supracloacal chromolipoid body, which has no counterpart among other warm blooded animals. The organ occurs in both sexes and in birds of different ages. It is located in the median sagittal plane dorsal to the cloaca. It is enveloped by a smooth muscle-connective tissue capsule and has a rich blood supply. The supracloacal body is yellow-brown in color being composed chiefly of islands of pigment cells.Histochemically, the pigment is a chromolipoid as defined by Ciaccio.