Cryptic Speciation in Brazilian Epiperipatus (Onychophora: Peripatidae) Reveals an Underestimated Diversity among the Peripatid Velvet Worms

Taxonomical studies of the neotropical Peripatidae (Onychophora, velvet worms) have proven difficult, due to intraspecific variation and uniformity of morphological characters across this onychophoran subgroup. We therefore used molecular approaches, in addition to morphological methods, to explore the diversity of Epiperipatus from the Minas Gerais State of Brazil.Our analyses revealed three new species. While Epiperipatus diadenoproctussp. nov. can be distinguished from E. adenocryptussp. nov. and E. paurognostussp. nov. based on morphology and specific nucleotide positions in the mitochondrial cytochrome c oxidase subunit I (COI) and small ribosomal subunit RNA gene sequences (12S rRNA), anatomical differences between the two latter species are not evident. However, our phylogenetic analyses of molecular data suggest that they are cryptic species, with high Bayesian posterior probabilities and bootstrap and Bremer support values for each species clade. The sister group relationship of E. adenocryptussp. nov. and E. paurognostussp. nov. in our analyses correlates with the remarkable morphological similarity of these two species. To assess the species status of the new species, we performed a statistical parsimony network analysis based on 582 base pairs of the COI gene in our specimens, with the connection probability set to 95%. Our findings revealed no connections between groups of haplotypes, which have been recognized as allopatric lineages in our phylogenetic analyses, thus supporting our suggestion that they are separate species.Our findings suggest high cryptic species diversity and endemism among the neotropical Peripatidae and demonstrate that the combination of morphological and molecular approaches is helpful for clarifying the taxonomy and species diversity of this apparently large and diverse onychophoran group

The relationship between humidity, light and the activity pattern of a velvet worm, Epiperipatus sp. (Onychophora: Peripatidae), from Bahía Drake, South Pacific of Costa Rica

<div><p>Abstract Even though the Onychophora represent a whole phylum, observations of their activity pattern in nature are almost non-existent. Here we report on the relationship between humidity and light and activity pattern of a new species of velvet worm, genus Epiperipatus, from four years of field observations in the South Pacific of Costa Rica. We found that most activity occurs during the driest and darkest nights of the year, in contrast with theoretical predictions.</p></div

Helicobacter pylori in a Costa Rican dyspeptic patient population

Artículo científico -- Universidad de Costa Rica, Instituto de Investigaciones en Salud. 1994. Este documento es privado debido a limitaciones de derechos de autor.Gastric biopsies from 65 Costa Rican dyspeptic patients were investigated for the presence ofHelicobacter pylori DNA by polymerase chain reaction (PCR) amplification of 16S rRNA sequences. Both frozen and paraffin-embedded samples were used, and the results were compared with bacterial culture and histological examination.Helicobacter pylori DNA was detected by PCR in 60 (92 %) of the patients, andHelicobacter pylori strains confirmed by PCR could be isolated from 37 of them. Altogether, 59 patients were shown to be infected using the combination of culture and histology as the reference method. The sensitivity of PCR analysis of frozen material was 98 % (58/59). The PCR analysis of paraffin-embedded samples seemed less reliable than that of frozen biopsy material.Universidad de Costa Rica. Instituto de Investigaciones en SaludUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA

Composition and Gene Expression of the cag Pathogenicity Island in Helicobacter pylori Strains Isolated from Gastric Carcinoma and Gastritis Patients in Costa Rica

The composition and in vitro expression of the cag pathogenicity island genes in a group of Helicobacter pylori strains obtained from patients suffering from chronic gastritis-associated dyspepsia (n = 26) or gastric carcinoma (n = 17) were analyzed. No significant difference in the distribution of the 10 studied regions was found between the cases and the controls. Nine strains did not harbor any of the selected regions: eight (30.8%) isolated from patients with gastritis only and one (5.9%) from a patient with gastric carcinoma. No association was found between the number of repeated sequences at the 3′ end of the cagA gene or the presence of tyrosine phosphorylation motifs and the clinical origin of the strains. The virB10 homolog gene was the sole gene studied to be significantly expressed more often in cancer strains than in gastritis strains (P = 0.03)

Comparative animal mucomics: inspiration for functional materials from ubiquitous and understudied biopolymers

The functions of secreted animal mucuses are remarkably diverse and include lubricants, wet adhesives, protective barriers, and mineralizing agents. Although present in all animals, many open questions related to the hierarchical architectures, material properties, and genetics of mucus remain. Here, we summarize what is known about secreted mucus structure, describe the work of research groups throughout the world who are investigating various animal mucuses, and relate how these studies are revealing new mucus properties and the relationships between mucus hierarchical structure and hydrogel function. Finally, we call for a more systematic approach to studying animal mucuses so that data sets can be compared, omics-style, to address unanswered questions in the emerging field of mucomics. One major result that we anticipate from these efforts is design rules for creating new materials that are inspired by the structures and functions of animal mucuses