The vocal sac of Hylodidae (Amphibia, Anura): Phylogenetic and functional implications of a unique morphology

Anuran vocal sacs are elastic chambers that recycle exhaled air during vocalizations and are present in males of most species of frogs. Most knowledge of the diversity of vocal sacs relates to external morphology; detailed information on internal anatomy is available for few groups of frogs. Frogs of the family Hylodidae, which is endemic to the Atlantic Forest of Brazil and adjacent Argentina and Paraguay, have three patterns of vocal sac morphology-that is, single, subgular; paired, lateral; and absent. The submandibular musculature and structure of the vocal sac mucosa (the internal wall of the vocal sac) of exemplar species of this family and relatives were studied. In contrast to previous accounts, we found that all species of Crossodactylus and Hylodes possess paired, lateral vocal sacs, with the internal mucosa of each sac being separate from the contralateral one. Unlike all other frogs for which data are available, the mucosa of the vocal sacs in these genera is not supported externally by the mm. intermandibularis and interhyoideus. Rather, the vocal sac mucosa projects through the musculature and is free in the submandibular lymphatic sac. The presence of paired, lateral vocal sacs, the internal separation of the sac mucosae, and their projection through the m. interhyoideus are synapomorphies of the family. Furthermore, the specific configuration of the m. interhyoideus allows asymmetric inflation of paired vocal sacs, a feature only reported in species of these diurnal, stream-dwelling frogs.

Cancer vaccine characterization: from bench to clinic

BACKGROUND

The development of safe, effective, and affordable vaccines has become a global effort due to its vast impact on overall world health conditions. A brief overview of vaccine characterization techniques, especially in the area of high-resolution mass spectrometry, is presented. It is highly conceivable that the proper use of advanced technologies such as high-resolution mass spectrometry, along with the appropriate chemical and physical property evaluations, will yield tremendous in-depth scientific understanding for the characterization of vaccines in various stages of vaccine development. This work presents the physicochemical and biological characterization of cancer vaccine Racotumomab/alumina, a murine anti-idiotypic antibody that mimics N-glycolyl-GM3 gangliosides. This antibody has been tested as an anti-idiotypic cancer vaccine, adjuvated in Al(OH)3, in several clinical trials for melanoma, breast, and lung cancer.

METHODS

Racotumomab was obtained from ascites fluid, transferred to fermentation in stirred tank at 10 L and followed to a scale up to 41 L. The mass spectrometry was used for the determination of intact molecule, light and heavy chains masses; amino acids sequence analysis, N- and C-terminal, glycosylation and posttranslational modifications. Also we used the DLS for the size distribution and zeta potential analysis. The biological analyses were performed in mice and chickens.

RESULTS

We observed differences in glycosylation pattern, charge heterogeneity and structural stability between in vivo-produced and bioreactor-obtained Racotumomab products. Interestingly, these modifications had no significant impact on the immune responses elicited in two different animal models.

CONCLUSIONS

We are demonstrated that this approach could potentially be more efficient and effective for supporting vaccine research and development.

Análisis comparativo de las características neuropsicológicas de pacientes con demencia fronto-temporal, variante conductual y enfermedad de Alzheimer

Objetivo: Describir las características neuropsicológicas de pacientes con demencia frontotemporal varianteconductual (DFTvc) y compararlas con las de pacientes con enfermedad de Alzheimer (EA). Pacientes y métodos:Se evaluó una muestra de 60 controles sanos, 60 pacientes con EA y 32 pacientes con DFTvc, empleando una bateríaneuropsicológica clásica. Resultados: Los pacientes con DFTvc tienen peor rendimiento que pacientes con EA enalgunos parámetros de atención y funciones ejecutivas (FE) y menor compromiso de la memoria. La evaluaciónde atención muestra diferencia altamente significativa en el rendimiento del Trail Making Test (TMT)-A entre EAy DFTvc (t28=-2,18, p<0,001). De la misma manera, en la evaluación de FE, sólo el TMT-B (t31= -6,8, p<0,001) ylas respuestas perseverativas en el Wisconsin Card Sorting Test (WCST) (U = 30,5, p<0,001) alcanzaron diferenciaestadísticamente significativa entre los grupos EA y DFTvc. Conclusiones: Los pacientes con DFTvc en estadiosleve a moderado presentan una relativa menor afectación de memoria, lenguaje y habilidades viso-constructivas/viso-espaciales, pero con un marcado deterioro de atención y FE.

Frogs and toads of the Pedra Azul–Forno Grande Biodiversity Corridor, southeastern Brazil

We conducted a long-term amphibian survey at the biodiversity corridor Pedra Azul-Forno Grande, in the mountain region of the state of Espírito Santo, Brazil. Sampling was conducted from April 2004 to October 2009 and we registered 43 species. Two species (Dendropsophus ruschii and Megaelosia apuana) are included in the state list of threatened species and Scinax belloni is included in the IUCN/GAA list. We provide color photographs for most species found in the region.

Characterization of Mucor pusillus rennin expressed in Pichia pastoris: enzymic, spectroscopic and calorimetric studies

The aspartic proteinase gene of Mucor pusillus rennin expressed in Pichia pastoris was characterized in terms of structural and conformational stability induced by temperature. This enzyme is 12% glycosylated, with a similar specific activity to the native fungal enzyme. The secondary structure determined by CD is mainly due to beta-sheet structures with an important contribution of aromatic components. The calorimetric studies were carried out in the temperature range in which the enzyme is most stable. The enzyme undergoes an irreversible, highly scan-rate-dependent thermal denaturation under all the experimental conditions investigated. Between pH 3.0 and 7.0, only one endotherm characterized the thermal denaturation of enzyme. At pH 5.0, the most stable condition found, the denaturation can be fitted to the two-state irreversible model. Thus the kinetic constant and activation parameters of the denaturation process could be obtained. Upon reaching pH 7.5, the denaturation is characterized by two endotherms. This evidence indicates the complex tridimensional structure of this enzyme. Finally, taking into account the conservative tertiary structure of the aspartic proteinase family we comment on our results with reference to the crystallographic structure of M. pusillus pepsin [Newman, Watson, Roychowdhury, Badasso, Cleasby, Wood, Tickle and Blundell (1993) J. Mol. Biol. 221, 1295-1309].

Invertase secretion in Hansenula polymorpha under the AOX1 promoter from Pichia pastoris

A DNA fragment containing a transcription regulating region of the alcohol oxidase (AOX1) gene from the methylotrophic yeast Pichia pastoris was used in the construction of a vector for the expression of heterologous proteins in the methylotrophic yeast Hansenula polymorpha. We used this vector to clone the SUC2 gene from Saccharomyces cerevisiae into H. polymorpha yeast. The culture conditions for invertase production using a fed-batch culture were studied. More than 1.5 x 10(3) U/ml of biologically active invertase (1 g/l) were secreted to the cellular periplasmic space. The fermentative process was scaled up to 50 l. Invertase produced from H. polymorpha was glycosylated, but it contained significantly less carbohydrate than protein produced by S. cerevisiae. Using the Western-blot technique, it was observed that invertase secreted from H. polymorpha and invertase secreted from S. cerevisiae showed common antigenic determinants.

High level expression of the B. microplus Bm86 antigen in the yeast Pichia pastoris forming highly immunogenic particles for cattle

Recently, a gene coding for the Bm86 tick gut glycoprotein was cloned, expressed in Escherichia coli and shown to induce an immunological response in cattle to damage ticks engorging on these animals (Rand et al., 1989). We report here the increased expression of the Bm86 antigen from the cattle tick Boophilus microplus in the methylotrophic yeast Pichia pastoris. The recombinant protein was obtained with a purity higher than 95% by a procedure with a high yield. The conducted biochemical studies demonstrated the antigen to be glycosylated and found to form particles of around 17 to 45 nm in diameter with enhanced immunogenic properties. Ticks engorging on vaccinated cattle were significantly damaged as a result of the immune response against the recombinant antigen. This system permits the obtainment in a high yield of the tick Bm86 antigen, in a glycosylated and particulated form.