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Metopid armophoreans are ciliates commonly found in anaerobic environments worldwide; however, very little is known of their fine structure. In this study, the metopid Parametopidium circumlabens (Biggar and Wenrich 1932) Aescht, 1980, a common endocommensal of sea urchins, is investigated for the first time with emphasis on transmission electron microscopy, revealing several previously unknown elements of its morphology. Somatic dikinetids of P. circumlabens have a typical ribbon of transverse microtubules, an isolated microtubule near triplets 4 and 5 of the anterior kinetosome, plus two other microtubules between anterior and posterior kinetosomes, a short kinetodesmal striated fiber and long postciliary microtubules. In the dikinetids of the perizonal stripe, the kinetodesmal fiber is very pronounced, and there is a conspicuous microfibrillar network system associated with the kinetosomes. A new structure, shaped as a dense, roughly cylindrical mass surrounded by microtubules, is found associated with the posterior kinetosome of perizonal dikinetids. The paroral membrane is diplostichomonad and the adoral membranelles are of the 'paramembranelle' type. Bayesian inference and maximum-likelihood analysis of the 18S- rDNA gene unambiguously placed P. circumlabens as sister group of the cluster formed by (( Atopospira galeata, Atopospira violacea) Metopus laminarius) + Clevelandellida, corroborating its classification within the Metopida. [ABSTRACT FROM AUTHOR]

Pseudokeronopsidae Borror & Wicklow, 1983 are biotechnologically important ciliate protists which produce toxic defense substances; however, their diversity is still little known in Brazil. In the present study, Tetrakeronopsis silvanetoi, a new genus and species of marine pseudokeronopsid hypotrichs is described from samples of water with bottom sediment collected from the coast of São Paulo state. Its phylogenetic affinities to the “core urostyloids” are hypothesized based on analyses of the 18S-rDNA marker, and a new subfamily, the Nothoholostichinae subfam. nov., is erected to name the monophylum composed of pseudokeronopsids in which the anterior corona is usually formed by four frontal cirri. In addition, the new combination Monocoronella longissima comb. nov. is proposed for Nothoholosticha longissima (Dragesco & Dragesco-Kernéis, 1986) Li et al., 2009. [ABSTRACT FROM AUTHOR]

Gastric cancer is the forth malignancy in frequency in the world. In the northern Brazil is the second neoplasia most frequent in males and the third most frequent in females. Genetic and epigenetic alterations are evolved on gastric carcinogenesis and DNA methylation is the epigenetic alteration better studied. We analyzed de novo DNA methyltransferases methylation pattern and its association with RUNX3 gene methylation pattern in Brazilian samples of intestinal-type and diffuse-type of gastric cancer. PCR methylation specific was used to evaluate DNA methylation pattern. Sixty-six samples were studied in this work. Only the gene RUNX3 presented altered methylation pattern, being methylated in 38.5% of gastric cancer intestinal-type samples and in 70% of gastric cancer diffuse-type samples and, by this reason, it should be evolved in the genesis of this neoplasia. There was a statistically significant difference among diffuse-type and intestinal-type samples (p=0.0418) and among normal and tumour tissues (p<0.0001) for RUNX3 gene but not to DNMT3A, DNMT3B e DNMT3 genes on CpG islands analyzed. Alteration of RUNX3 methylation pattern is not associated to de novo alteration of DNA methyltransferases methylation pattern on studied regions. Therefore, it becomes necessary a better comprehension of this phenomenon on gastric carcinogenesis. [ABSTRACT FROM AUTHOR]

Metopid armophoreans are ciliates commonly found in anaerobic environments worldwide; however, very little is known of their fine structure. In this study, the metopid Parametopidium circumlabens (Biggar and Wenrich 1932) Aescht, 1980, a common endocommensal of sea urchins, is investigated for the first time with emphasis on transmission electron microscopy, revealing several previously unknown elements of its morphology. Somatic dikinetids of P. circumlabens have a typical ribbon of transverse microtubules, an isolated microtubule near triplets 4 and 5 of the anterior kinetosome, plus two other microtubules between anterior and posterior kinetosomes, a short kinetodesmal striated fiber and long postciliary microtubules. In the dikinetids of the perizonal stripe, the kinetodesmal fiber is very pronounced, and there is a conspicuous microfibrillar network system associated with the kinetosomes. A new structure, shaped as a dense, roughly cylindrical mass surrounded by microtubules, is found associated with the posterior kinetosome of perizonal dikinetids. The paroral membrane is diplostichomonad and the adoral membranelles are of the "paramembranelle" type. Bayesian inference and maximum-likelihood analysis of the 18S-rDNA gene unambiguously placed P. circumlabens as sister group of the cluster formed by ((Atopospira galeata, Atopospira violacea) Metopus laminarius) + Clevelandellida, corroborating its classification within the Metopida., (© 2015 The Author(s) Journal of Eukaryotic Microbiology © 2015 International Society of Protistologists.)

Unlabelled: The aim of this study was to investigate the protein expression and methylation pattern of P21(CIP1) and P27(KIP1) genes., Patients and Methods: Twenty samples of gastric tumor and non-tumoral tissues of patients from Pará state, Brazil were collected. Methylation patterns were assessed by bisulfite sequencing, and protein expression evaluated with immunohistochemical analysis., Results: None of the analyzed samples showed methylation in both genes. Immunohistochemistry analysis demonstrated mislocalization or absence of expression of P21(CIP1) and P27(KIP1) in 7/20 and 6/20 of the studied samples, respectively. No correlations regarding protein expression and clinicopathological characteristics were observed; down-regulation of expression of P21(CIP1) with low (I-II) tumor stage (p=0.0777), and older age (>50 years old) with negative or mislocalization of P27(KIP1) (p=0.0922) were of borderline the statistical significance., Conclusion: Our results suggest that hypermethylation does not contribute to P21(CIP1) and P27(KIP1) silencing in gastric cancer, and that the role of these genes in the gastric tumorigenesis pathways should be studied further in the Pará state population.

Unlabelled: The aim of this study was to verify genetic and epigenetic alterations in gastric cancer patients from Pará state, northern Brazil., Materials and Methods: Exon 11 of KIT and two promoter polymorphisms (-160 C/A and -347 G/GA) of the E-cadherin gene (CDH1), and their correlation with the promoter methylation status were analyzed., Results: No genetic alterations in KIT were found. Promoter polymorphisms revealed an increased probability of developing gastric cancer, especially of the diffuse-type, in patients carrying -160 A and -347 GA alleles. Analyses of CDH1 methylation suggested a significant difference between hypermethylated and non-hypermethylated samples, with a positive association between the -160 A allele and hypermethylation., Conclusion: Our results suggest that -160 A and -347 GA polymorphisms may increase the chance of developing gastric cancer in the studied population and that -160 A polymorphism seems to be related to the hypermethylation pattern of the promoter region of CDH1.

Piper tuberculatum is an exotic Piper from the Amazon region that shows resistance to infection by Fusarium solani f. sp. piperis, causal agent of Fusarium disease in black pepper (Piper nigrum L.). In this work we aimed to study the interaction between P. tuberculatum and F. solani f. sp. piperis at a molecular level, using suppression subtractive hybridization to identify genes potentially related to Fusarium disease resistance. Comparative sequence analysis confirmed that clones isolated here show a high identity with genes coding for proteins that have a known role in plant defense response mechanisms, such as peroxidase, hydroxyproline-rich glycoprotein and CBL-interacting protein kinase. The present study constitutes the first effort to understand the molecular basis of this plant-pathogen interaction, identifying genes which may be used in the future genetic improvement of black pepper.