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We describe a pericapillary organ in the rat forebrain and cerebellar cortex. It consists of series of tripartite synapses enveloped by astrocytic endfeet linked to the capillary wall by synaptic extensions. Reciprocal specializations of the pericyte-capillary blood vessel with such specialized synapses suggests a mechanoreceptor role. In Golgi impregnated and 3D reconstructions of cerebral cortex and thalamus, series of tripartite synapses appear sequentially ordered in a tributary dendrite paralleled by synaptic outgrowths termed here golf club-like extensions apposed to a longitudinal crest from the capillary basal lamina. To facilitate identification of principal cell dendrites and arriving axons to these putative mechanosensory structures, we utilized the cerebellar cortex since it has a well known organization and observed that afferent fibers and interneurons display interactions with the capillary wall. Afferent mossy fiber rosettes and ascending granule cell axons and dendrites define pericapillary on passage interactions surrounded by endfeet. The ability of such structures to modulate synaptic transmission is supported by the presence of mRNA of the mechanosensitive channel Piezo 1 in the mossy fiber rosettes, pyramidal isocortical and thalamic neurons. This suggests that ascending impulses to the cerebellar and cortical targets are presynaptically modulated by the reciprocal interaction with the mechanosensory pericapillary organ.

We surveyed a subsurface layer of saturated mobile mud and its microbial fingerprints below the desiccated bottom of a maar lake at Rincón de Parangueo (RP), Mexico. A multi-scale approach was followed using geological fieldwork, coring of the sediments, ground penetrating radar survey, physico-chemical characterization including X-ray diffraction and scanning electron microscope, and high-throughput DNA sequencing methods. The mobile mud is an organic-rich silty clay, with high values of alkalinity, volumetric water content and conductivity. Mud mobility has been attributed to overpressure caused by disequilibrium compaction of sediments related to active subsidence and pore overpressure produced by an input of groundwater and gas content in the sediments and resulted in a diverse set of structures related to mud tectonics such as injection domes and fluid seeps through fractures. Extraction and sequencing of sedimentary environmental DNA in the mud layer were performed for Bacteria and Archaea. Despite the small number of samples obtained, the microbial fingerprint from the sedimentary environmental DNA at subsurface shares similarities with the microbial communities identified on the crater surface. Additionally, we identify the DNA of specific methanogenic microorganisms in the mud, such as Bathyarchaeia, Methanomassiliicoccales, and Methanobacteriales, and we speculate on their probable role in gas production and pore overpressure in the mud layer. The underground mud at Rincón de Parangueo represents a geologically dynamic environment with conditions that are favorable for the thriving of microbial communities.

Tissue engineering has been able to develop novel decellularization-recellularization techniques, which facilitates the research for the generation of functional organs. This is based in the initial obtention of the organ's extracellular matrix (ECM). Therefore, any improvement in the decellularization process would have a positive impact in the results of the recellularization process. Nevertheless, commonly the methods and equipment employed for this process are expensive and thus limit the access of this technique to various research groups globally. To develop a decellularization technique with the exclusive use of hydrostatic pressure of detergent solutions, to have an easily accessible and low-cost technique that meets the basic requirements of acellularity and functionality of the ECM. This experimental study was performed in 10 male Wistar rats, obtaining the liver to carry out serial washes, with 1%, 2%, and 3% Triton X-100 solutions and 0.1% SDS. The washes were performed by using a gravity perfusion system (GPS), which assured us a continuous hydrostatic pressure of 7.5 mmHg. The obtained ECM was processed using stains and immunostaining to determine the residual cell content and preservation of its components. The staining showed a removal of cellular and nuclear components of approximately 97% of the acellular ECM, with an adequate three-dimensional pattern of collagen and proteoglycans. Furthermore, the acellular ECM allowed the viability of a primary hepatocyte culture. The use of the GPS decellularization technique allowed us to obtain an acellular and functional ECM, drastically reducing experimentation costs.

Probiotics are live microorganisms that confer health benefits to their animal host by balancing the composition of its gastrointestinal microbiota and modulating its immune response. In this work, we studied bacterial consortia isolated from the rumen of 28- and 42-day-old calves to select those showing probiotic capacity. Consortia were characterized and their growth dynamics were determined in several growth media. The number of viable bacteria was larger in the Man, Rogosa and Sharpe broth (MRS) than in nutritive medium A (MNA) and the largest was for A3D42. Antibiotic susceptibility of bacterial consortia in MRS was higher than in MNA and the most susceptible samples were A1D28 and A3D42. In turn, A3D42 showed the highest tolerance to bile salts in MRS and MNA. Moreover, all bacterial consortia showed optimal growth at pH 5, 5.5, 6 and 7 in both media, while their temperature tolerance was higher in MRS. The antagonistic activity of bacterial consortia in MNA was higher than in MRS with A2D42 showing the best antagonistic activity for Pseudomona aureginosa (ATCC 9027) and Staphylococcus aureus (ATCC 6538) in MNA. Additionally, A1D42 and A2D42 in MRS and A3D42 in MNA had significant adhesion to mucins, and A1D42 in MRS had the highest. Regarding their species composition, all bacterial consortia in MRS belonged to the phylum Firmicutes, and the class Bacilli and bacterial consortia in MNA belonged to three phyla; Proteobacteria, Firmicutes, and Bacteroidetes. Lactobacillus casei, Lactobacillus rhamnosus, Lactobacillus fermentum, and Lactobacillus johnsonii were identified in all bacterial consortia in MRS broth. Based on these results, A1D42 and A3D42 grown in MRS showed the best potential as probiotics for calves, which could result in health benefits and improve their production.

Spatiotemporal regulation of cAMP within the cell is required to achieve receptor-specific responses. The mechanism through which the cell selects a specific response to newly synthesized cAMP is not fully understood. In hepatocyte plasma membranes, we identified two functional and independent cAMP-responsive signaling protein macrocomplexes that produce, use, degrade, and regulate their own nondiffusible (sequestered) cAMP pool to achieve their specific responses. Each complex responds to the stimulation of an adenosine G protein-coupled receptor (Ado-GPCR), bound to either A2A or A2B , but not simultaneously to both. Each isoprotein involved in each signaling cascade was identified by measuring changes in cAMP levels after receptor activation, and its participation was confirmed by antibody-mediated inactivation. A2A -Ado-GPCR selective stimulation activates adenylyl cyclase 6 (AC6), which is bound to AKAP79/150, to synthesize cAMP which is used by two other AKAP79/150-tethered proteins: protein kinase A (PKA) and phosphodiesterase 3A (PDE3A). In contrast, A2B -Ado-GPCR stimulation activates D-AKAP2-attached AC5 to generate cAMP, which is channeled to two other D-AKAP2-tethered proteins: guanine-nucleotide exchange factor 2 (Epac2) and PDE3B. In both cases, prior activation of PKA or Epac2 with selective cAMP analogs prevents de novo cAMP synthesis. In addition, we show that cAMP does not diffuse between these protein macrocomplexes or 'signalosomes'. Evidence of coimmunoprecipitation and colocalization of some proteins belonging to each signalosome is presented. Each signalosome constitutes a minimal functional signaling unit with its own machinery to synthesize and regulate a sequestered cAMP pool. Thus, each signalosome is devoted to ensure the transmission of a unique and unequivocal message through the cell.

Rincon de Parangueo is a maar where a perennial lake was present until the 1980s. A conspicuous feature of the lake’s sediments is the presence of bioherms and organo-sedimentary deposits produced by microbial communities. The gradual lake desiccation during the last 40 years has produced dramatic environmental changes inside the maar basin, which resulted in the formation of a highly saline-alkaline system with extant microorganisms. In this paper we succinctly describe the geologic setting where the microbial communities have developed inside of the maar crater and the results obtained from high-throughput sequencing methods to characterize the microbial component (Bacteria, Eukarya and Archaea) in endolithic mats of calcareous sediments, and microbial mats and free-living microorganisms in the soda ponds. The studied sites displayed different microbial communities with a diverse number of phylotypes belonging to Bacteria and Eukarya, contrasting with a much less diverse component in Archaea. The sequences here detected were related to environmental sequences from sites with extreme life conditions such as high alkalinity (alkaliphiles), high salinity (halophiles) and high temperature (thermophiles). Moreover, our results indicate an important unexplored endemic microbial biodiversity in the vestiges of the former lake that need to be studied.

Stereotypic cell migrations in the developing brain are fundamental for the proper patterning of brain regions and formation of neural networks. In this work, we uncovered in the developing rat, a population of neurons expressing tyrosine hydroxylase (TH) that migrates posteriorly from the alar plate of the midbrain, in neurophilic interaction with axons of the mesencephalic nucleus of the trigeminal nerve. A fraction of this population was also shown to traverse the mid-hindbrain boundary, reaching the vicinity of the locus coeruleus (LC) in rhombomere 1 (r1). This migratory population, however, does not have a noradrenergic (NA) phenotype and, in keeping with its midbrain origin, expresses Otx2 which is down regulated upon migration into the hindbrain. The interaction with the trigeminal mesencephalic axons is necessary for the arrangement and distribution of migratory cells as these aspects are dramatically altered in whole embryo cultures upon disruption of trigeminal axon projection by interfering with DCC function. Moreover, in mouse embryos in an equivalent developmental stage, we detected a cell population that also migrates caudally within the midbrain apposed to mesencephalic trigeminal axons but that does not express TH; a fraction of this population expresses calbindin instead. Overall, our work identified TH-expressing neurons from the rat midbrain alar plate that migrate tangentially over long distances within the midbrain and into the hindbrain by means of a close interaction with trigeminal mesencephalic axons. A different migratory population in this region and also in mouse embryos revealed diversity among the cells that follow this descending migratory pathway.

Purpose: The aim of this work was to evaluate the effect of PPAR agonists on the differentiation and metabolic features of porcine mesenchymal stem cells induced to the adipogenic or myogenic lineages. Methods: Bone marrow MSCs from neonate pigs were isolated and identified by cell proliferation, cell surface markers or the gene expression of stem cells (CD44, CD90, CD105 or Oct4 and Nanog, respectively). Cells were differentiated into adipose or muscle cells and treated with the PPAR agonists; adipogenic and myogenic differentiation was promoted by adding these compounds. The expression of PPARγ (an adipose marker) and MyoD1 and MyHC (muscle markers), metabolic changes and expression levels of metabolic enzymes involved in glycolysis, lipogenesis, lipolysis and the pentose phosphate pathway were tested by qPCR. Results: MSCs from neonate pigs exhibited high proliferation and were positive for CD44, CD90 and CD105 markers and Oct4 and Nanog expression. The treatment that promoted the highest expression of PPARγ was 50 µM of conjugated linoleic acid (CLA) c9 t11 (6.44 ± 0.69-fold, p ≤ 0.0001) in the adipose differentiation, and upregulation of HX2, ACCAα, ATGL, LPL and G6DP (p ≤ 0.0001) and downregulation of PFK and ACCAβ (p ≤ 0.0001) were found. For muscle differentiation, the best treatment was 50 µM of CLA c10 t12 (59.72 ± 4.72-fold, p ≤ 0.0001), and metabolic changes were upregulation of PFK, ACCAβ, G6DP, CPT1 and PPARβ/δ (p ≤ 0.0001), but no effect was observed with HX2 and ACCAα (p ≥ 0.05). Conclusions: Our results suggest that differentiated cells exhibit a typical cell lineage metabolism and higher efficiencies both in anabolism and catabolism.