A Morphological and Ultrastructural Study of the Anterior Digestive Tract of Adult Nile Tilapia Oreochromis niloticus.

Among the most-used fish species in aquaculture is the Nile tilapia, due to its rapid growth rate and its adaptation to a wide range of farming conditions. A careful description of the morphology of the digestive tract, particularly the esophagus and stomach, allows a better understanding of the relationship between structure and function. Combining scanning and light microscopy we highlighted the presence of five different zones in the stomach (1: esophagus-gastric lumen passage; 2: descending glandular portion; 3: fundic portion; 4: ascending glandular portion; 5: gastric-pyloric transition portion). Histochemical investigation showed a secretion of carboxylates mucopolysaccharides along the esophagus and sulphated complex carbohydrates in the stomach. These results suggest that mucins play a protective role of the epithelial lining, which is essential for a correct digestive process. Finally, the characterization of the main cellular structures may be inspiring for more advanced studies aiming to decipher the role of specific molecules, such as neuropeptides, involved in the physiological digestive process.

Integration of micro-CT and histology data for vasculature morpho-functional analysis in tissue regeneration.

The demand for artificial or bioartificial engineered tissues is increasing today in regenerative medicine techniques to replace and restore the physiological function of damaged tissues. Such engineered constructs hold different properties depending on the tissue to be replicated. As for vascularized tissues, complex biocompatible structures, namely scaffolds, play a key role in supporting oxygen and nutrient supply, thus sustaining tissue neoformation and integration with the host. Scaffold architecture significantly impacts its regenerative potential, while preclinical trials are essential to define scaffold-host interactions. In compliance with the 3 R principle, there is a clear need to optimize both the procedures to evaluate scaffold performance and the analysis methodology decreasing the number of animals required to gain consistent data. In parallel, current technologies used in preclinical research generate huge amounts of data that need to be elaborated and interpreted correctly. Therefore, we designed this study to evaluate the results of scaffold integration with the host tissue after implantation in a mouse subcutaneous pocket model. We evaluated the angiogenic response developed by the host and the degree of scaffold integration by using a combined morphometric approach based on both histological and micro-CT analyses. Six-layer scaffolds, made of polycaprolactone (PCL) microspheres, with an ordered structure were produced by thermal sintering. Scaffolds were then implanted in BALB/c mice and retrieved 21 days post-implantation when the animals were deeply anesthetized and perfused with Microfil, a contrast agent for micro-CT. Here, we describe a method to extract quantitative data from micro-CT reconstructions such as (i) total vessel volume; (ii)% of vessel penetration; (iii) distribution of vessel diameters. The general principle of this approach is the refinement of the region of interest (ROI), thus producing a volume of interest (VOI) that matches scaffold volume. This VOI serves as a dataset from which to extract volumetric information. Then VOIs are divided into three identical parts, proximal, median, and distal, to follow the vessel progression into the scaffold, thus obtaining their depth of penetration (DoP). By this methodology, we observed in mean, among the analyzed samples, a vessel invasion for 1,38 mm3 corresponding to the 1,53% of the scaffold volume. We then looked at the diameter distribution being this value a key indicator of vessel maturity, highlighting that 55% of vessels fall into the range from 5,99-53.99 µm while the remaining 45% are distributed into intervals from 54 to 136 µm. In parallel, to evaluate tissue integration in detail, histological and immunofluorescent analyses were performed to look at vessel distribution and collagen synthesis. Histological results strongly correlate with the micro-CT data providing, however, an overview of the ingrowth tissues. In addition, by immunofluorescent analysis we demonstrate that newly formed vessels are mature at the considered time point and tissue collagen deposition is widespread within the scaffolds. Collectively, we propose a new method to track vessel formation by using a multi-modal approach posing the basis for: i) the fabrication of novel scaffolds for Tissue Engineering; ii) the integration of detailed information for a wide range of morphological and functional analyses.

The fate of cigarette butts in different environments: Decay rate, chemical changes and ecotoxicity revealed by a 5-years decomposition experiment.

Cigarette butts (CBs) are the most common litter item on Earth but no long-term studies evaluate their fate and ecological effects. Here, the role of nitrogen (N) availability and microbiome composition on CBs decomposition were investigated by a 5-years experiment carried out without soil, in park grassland and sand dune. During decomposition, CBs chemical changes was assessed by both 13C CPMAS NMR and LC-MS, physical structure by scanning electron microscope and ecotoxicity by Aliivibrio fischeri and Raphidocelis subcapitata. Microbiota was investigated by high-throughput sequencing of bacterial and eukaryotic rRNA gene markers. CBs followed a three-step decomposition process: at the early stage (∼30 days) CBs lost ∼15.2% of their mass. During the subsequent two years CBs decomposed very slowly, taking thereafter different trajectories depending on N availability and microbiome composition. Without soil CBs showed minor chemical and morphological changes. Over grassland soil a consistent N transfer occurs that, after de-acetylation, promote CBs transformation into an amorphous material rich in aliphatic compounds. In sand dune we found a rich fungal microbiota able to decompose CBs, even before the occurrence of de-acetylation. CBs ecotoxicity was highest immediately after smoking. However, for R. subcapitata toxicity remained high after two and five years of decomposition.

Biochars from olive mill waste have contrasting effects on plants, fungi and phytoparasitic nematodes.

Olive mill waste (OMW), a byproduct from the extraction of olive oil, causes serious environmental problems for its disposal, and extensive efforts have been made to find cost-effective solutions for its management. Biochars produced from OMW were applied as soil amendment and found in many cases to successfully increase plant productivity and suppress diseases. This work aims to characterize biochars obtained by pyrolysis of OMW at 300 °C to 1000 °C using 13C NMR spectroscopy, LC-ESI-Q-TOF-MS and SEM (Scanning Electron Microscopy). Chemical characterization revealed that biochar composition varied according to the increase of pyrolysis temperature (PT). Thermal treated materials showed a progressive reduction of alkyl C fractions coupled to the enrichment in aromatic C products. In addition, numerous compounds present in the organic feedstock (fatty acids, phenolic compounds, triterpene acids) reduced (PT = 300 °C) or completely disappeared (PT ≥ 500 °C) in biochars as compared to untreated OMW. PT also affected surface morphology of biochars by increasing porosity and heterogeneity of pore size. The effects of biochars extracts on the growth of different organisms (two plants, one nematode and four fungal species) were also evaluated. When tested on different living organisms, biochars and OMW showed opposite effects. The root growth of Lepidium sativum and Brassica rapa, as well as the survival of the nematode Meloidogyne incognita, were inhibited by the untreated material or biochar produced at 300 °C, but toxicity decreased at higher PTs. Conversely, growth of Aspergillus, Fusarium, Rhizoctonia and Trichoderma fungi was stimulated by organic feedstock, while being inhibited by thermally treated biochars. Our findings showed a pattern of association between specific biochar chemical traits and its biological effects that, once mechanistically explained and tested in field conditions, may lead to effective applications in agriculture.

Lactoferrin Adsorbed onto Biomimetic Hydroxyapatite Nanocrystals Controlling - In Vivo - the Helicobacter pylori Infection.

BACKGROUND: The resistance of Helicobacter pylori to the antibiotic therapy poses the problem to discover new therapeutic approaches. Recently it has been stated that antibacterial, immunomodulatory, and antioxidant properties of lactoferrin are increased when this protein is surface-linked to biomimetic hydroxyapatite nanocrystals. OBJECTIVE: Based on these knowledge, the aim of the study was to investigate the efficacy of lactoferrin delivered by biomimetic hydroxyapatite nanoparticles with cell free supernatant from probiotic Lactobacillus paracasei as an alternative therapy against Helicobacter pylori infection. METHODS: Antibacterial and antinflammatory properties, humoral antibody induction, histopathological analysis and absence of side effects were evaluated in both in vitro and in vivo studies. RESULTS: The tests carried out have been demonstrated better performance of lactoferrin delivered by biomimetic hydroxyapatite nanoparticles combined with cell free supernatant from probiotic Lactobacillus paracasei compared to both lactoferrin and probiotic alone or pooled. CONCLUSION: These findings indicate the effectiveness and safety of our proposed therapy as alternative treatment for Helicobacter pylori infection.

Epistatic interaction between MyD88 and TIRAP against Helicobacter pylori.

The genes MyD88 and TIRAP encode the adaptor proteins MyD88 and TIRAP. TIRAP plays the crucial role of activating the MyD88-dependent pathway, which in turn controls the immune response (innate and adaptive) to Helicobacter pylori. We looked for an association of MyD88 and TIRAP with H. pylori infection. Cases and controls were genotyped at the polymorphic sites MyD88 rs6853 and TIRAP rs8177374 by real-time PCR. When the genes were analyzed separately, only TIRAP was associated with infection. When the genes were analyzed concurrently, certain combinations of MyD88 and TIRAP protected the host against H. pylori colonization more efficiently than could be done by TIRAP alone.