41 research outputs found
Genomic and proteomic analyses of Mycobacterium bovis BCG Mexico 1931 reveal a diverse immunogenic repertoire against tuberculosis infection
<p>Abstract</p> <p>Background</p> <p>Studies of <it>Mycobacterium bovis </it>BCG strains used in different countries and vaccination programs show clear variations in the genomes and immune protective properties of BCG strains. The aim of this study was to characterise the genomic and immune proteomic profile of the BCG 1931 strain used in Mexico.</p> <p>Results</p> <p>BCG Mexico 1931 has a circular chromosome of 4,350,386 bp with a G+C content and numbers of genes and pseudogenes similar to those of BCG Tokyo and BCG Pasteur. BCG Mexico 1931 lacks Region of Difference 1 (RD1), RD2 and N-RD18 and one copy of IS6110, indicating that BCG Mexico 1931 belongs to DU2 group IV within the BCG vaccine genealogy. In addition, this strain contains three new RDs, which are 53 (RDMex01), 655 (RDMex02) and 2,847 bp (REDMex03) long, and 55 single-nucleotide polymorphisms representing non-synonymous mutations compared to BCG Pasteur and BCG Tokyo. In a comparative proteomic analysis, the BCG Mexico 1931, Danish, Phipps and Tokyo strains showed 812, 794, 791 and 701 protein spots, respectively. The same analysis showed that BCG Mexico 1931 shares 62% of its protein spots with the BCG Danish strain, 61% with the BCG Phipps strain and only 48% with the BCG Tokyo strain. Thirty-nine reactive spots were detected in BCG Mexico 1931 using sera from subjects with active tuberculosis infections and positive tuberculin skin tests.</p> <p>Conclusions</p> <p>BCG Mexico 1931 has a smaller genome than the BCG Pasteur and BCG Tokyo strains. Two specific deletions in BCG Mexico 1931 are described (RDMex02 and RDMex03). The loss of RDMex02 (<it>fadD23</it>) is associated with enhanced macrophage binding and RDMex03 contains genes that may be involved in regulatory pathways. We also describe new antigenic proteins for the first time.</p
Resurrection and redescription of Varestrongylus alces (Nematoda; Protostrongylidae), a lungworm of the Eurasian moose (Alces alces), with report on associated pathology
Varestrongylus alces, a lungworm in Eurasian moose from Europe has been considered a
junior synonym of Varestrongylus capreoli, in European roe deer, due to a poorly detailed
morphological description and the absence of a type-series.
Methods
Specimens used in the redescription were collected from lesions in the lungs of Eurasian
moose, from Vestby, Norway. Specimens were described based on comparative morphology
and integrated approaches. Molecular identification was based on PCR, cloning and
sequencing of the ITS-2 region of the nuclear ribosomal DNA. Phylogenetic analysis
compared V. alces ITS-2 sequences to these of other Varestrongylus species and other
protostrongylids.
Results
Varestrongylus alces is resurrected for protostrongylid nematodes of Eurasian moose from
Europe. Varestrongylus alces causes firm nodular lesions that are clearly differentiated from
the adjacent lung tissue. Histologically, lesions are restricted to the parenchyma with adult,
egg and larval parasites surrounded by multinucleated giant cells, macrophages, eosinophilic
granulocytes, lymphocytes. The species is valid and distinct from others referred to
Varestrongylus, and should be separated from V. capreoli. Morphologically, V. alces can be
distinguished from other species by characters in the males that include a distally bifurcated
gubernaculum, arched denticulate crura, spicules that are equal in length and relatively short,
and a dorsal ray that is elongate and bifurcated. Females have a well-developed provagina,
and are very similar to those of V. capreoli. Morphometrics of first-stage larvae largely
overlap with those of other Varestrongylus. Sequences of the ITS-2 region strongly support
mutual independence of V. alces, V. cf. capreoli, and the yet undescribed species of
Varestrongylus from North American ungulates. These three taxa form a well-supported
crown-clade as the putative sister of V. alpenae. The association of V. alces and Alces or its
ancestors is discussed in light of host and parasite phylogeny and host historical
biogeography.
Varestrongylus alces is a valid species, and should be considered distinct from V. capreoli.
Phylogenetic relationships among Varestrongylus spp. from Eurasia and North America are
complex and consistent with faunal assembly involving recurrent events of geographic
expansion, host switching and subsequent speciation.
Cervidae, Cryptic species, Historical biogeography, ITS-2, Metastrongyloidea, Parasite
biodiversity, Varestrongylinae, Varestrongylus capreoli, Verminous pneumoniapublishedVersio
Hystricognathy vs Sciurognathy in the Rodent Jaw: A New Morphometric Assessment of Hystricognathy Applied to the Living Fossil Laonastes (Diatomyidae)
While exceptional for an intense diversification of lineages, the evolutionary history of the order Rodentia comprises only a limited number of morphological morphotypes for the mandible. This situation could partly explain the intense debates about the taxonomic position of the latest described member of this clade, the Laotian rock rat Laonastes aenigmamus (Diatomyidae). This discovery has re-launched the debate on the definition of the Hystricognathi suborder identified using the angle of the jaw relative to the plane of the incisors. Our study aims to end this ambiguity. For clarity, it became necessary to revisit the entire morphological diversity of the mandible in extant and extinct rodents. However, current and past rodent diversity brings out the limitations of the qualitative descriptive approach and highlights the need for a quantitative approach. Here, we present the first descriptive comparison of the masticatory apparatus within the Ctenohystrica clade, in combining classic comparative anatomy with morphometrical methods. First, we quantified the shape of the mandible in rodents using 3D landmarks. Then, the analysis of osteological features was compared to myological features in order to understand the biomechanical origin of this morphological diversity. Among the morphological variation observed, the mandible of Laonastes aenigmamus displays an intermediate association of features that could be considered neither as sciurognathous nor as hystricognathous
Visuospatial Integration: Paleoanthropological and Archaeological Perspectives
The visuospatial system integrates inner and outer functional processes, organizing spatial, temporal, and social interactions between the brain, body, and environment. These processes involve sensorimotor networks like the eye–hand circuit, which is especially important to primates, given their reliance on vision and touch as primary sensory modalities and the use of the hands in social and environmental interactions. At the same time, visuospatial cognition is intimately connected with memory, self-awareness, and simulation capacity. In the present article, we review issues associated with investigating visuospatial integration in extinct human groups through the use of anatomical and behavioral data gleaned from the paleontological and archaeological records. In modern humans, paleoneurological analyses have demonstrated noticeable and unique morphological changes in the parietal cortex, a region crucial to visuospatial management. Archaeological data provides information on hand–tool interaction, the spatial behavior of past populations, and their interaction with the environment. Visuospatial integration may represent a critical bridge between extended cognition, self-awareness, and social perception. As such, visuospatial functions are relevant to the hypothesis that human evolution is characterized by changes in brain–body–environment interactions and relations, which enhance integration between internal and external cognitive components through neural plasticity and the development of a specialized embodiment capacity. We therefore advocate the investigation of visuospatial functions in past populations through the paleoneurological study of anatomical elements and archaeological analysis of visuospatial behaviors
Our faces and brains
Neurological, cognitive and genetic sciences share a longstanding interest in studying the relationship between the shape of the human skull and of the brain. However, the downstream biological genetic underpinnings of such interactions, if they exist, remain largely unknown. A new genetic study now reports on a set of genes that may be involved in substantially shaping the profile of our face and the physical shape of our brain, but not so much its capabilities