A novel ex vivo porcine model of acid-induced esophageal damage for preliminary functional evaluations of anti-gastroesophageal reflux disease medical devices.

AIM: The aim of the study was to set up a porcine ex vivo model of acid-induced damage and to evaluate its performance by means of multichannel intraluminal impedance and pH (MII-pH) live recording, histology, and Evans blue (EB) permeability assay. MATERIALS AND METHODS: Thirteen esophagi, collected at a slaughterhouse, were ablated of their sphincters, pinned upright on a support, and placed in a thermostatic hood at 37°C with two infusion tubes and an MII-pH probe inserted in the top end. Three esophagi (histology controls) were only left in the hood for 3.5 h before sampling, while the remaining organs underwent the experimental protocol including saline infusion and recovery recording, and acid solution infusion and recovery recording. RESULTS: MII-pH analysis highlighted a significantly stronger decrease during acid infusion when compared to saline, but a better post-infusion recovery for saline solution. At the end of the protocol, MII was still statistically lower than baseline. The acid-damaged esophagi significantly absorbed more EB dye, and histology revealed strong mucosal exfoliation. CONCLUSION: The proposed model of esophageal acid damage seems to be repeatable, reliable, and achievable using organs collected at the slaughterhouse. MII recording proved to have good sensitivity in detecting mucosal alterations also in ex vivo trials.

In Vitro Effects of Tea Tree Oil (Melaleuca Alternifolia Essential Oil) and its Principal Component Terpinen-4-ol on Swine Spermatozoa.

The growing interest towards essential oils stems from their biological capabilities that include antibacterial and antioxidant effects. Such properties may be extremely useful in the reproductive field; nonetheless essential oils show toxic effects that can lead to cell disruption. The present study aimed to evaluate and compare the effects of tea tree oil (TTO) and its principal component terpinen-4-ol (TER) on the morpho-functional parameters of swine spermatozoa. Experimental samples were prepared by suspending 15 × 107 spermatozoa in 5 mL of medium with different concentrations of the above-mentioned compounds: from 0.2 to 2 mg/mL at an interval of 0.2 for TTO, while TER concentrations were adjusted according to its presence in TTO (41.5%). After 3 h incubation at 16 °C, samples were analyzed for pH, viability, acrosome status, and objective motility. The results highlighted a concentration-dependent effect of TTO with total motility as the most sensitive parameter. TER was better tolerated, and the most sensitive parameters were related to membrane integrity, suggesting a different pattern of interaction. The study confirms the importance of evaluating the effects of natural compounds on spermatozoa before exploiting their beneficial effects. Spermatozoa seem to be good candidates for preliminary toxicological screenings in the light of their peculiar properties.

1H NMR Spectroscopy Characterization of Porcine Vitreous Humor in Physiological and Photoreceptor Degeneration Conditions.

Purpose: Qualitative and quantitative analysis of vitreous humor (VH) is important to discriminate between physiological and pathological conditions and may be particularly helpful when using animal models for ophthalmologic research. The aim of the present study was to investigate the physiological qualitative/quantitative composition of the VH of the standard pig using a metabolomics approach based on 1H nuclear magnetic resonance (NMR) spectroscopy. A secondary aim was the characterization of the VH of the porcine model of photoreceptor degeneration induced with iodoacetic acid (IAA), widely used in the biomedical field, and comparison with the physiological one. Methods: VH samples were collected from 30 pigs (17 in the physiological condition and 13 treated with IAA) upon vitrectomy and analyzed by means of 1H NMR spectroscopy for characterization. Results: On all analyzed samples, 40 molecules could be identified and quantified, with lactate being the most abundant in both physiological and photoreceptor degeneration conditions. Upon comparison, only 17 molecules showed statistical differences: In the IAA group, glucose and glutamine increased, while lactate, 4-amynobutyrate, hypoxanthine, dicarboxylic acids (succinate and fumarate), amino acids with their derivatives (creatine, alanine, valine, lysine, leucine, glycine, taurine, and isoleucine), and choline with its precursor sn-glycero-3-phosphocholine decreased. Conclusions: The results validate the metabolic impairment determined by glycolysis inhibition upon systemic IAA administration. In conclusion, this work represents the first characterization of the porcine VH metabolome in physiological conditions and provides additional information for the characterization and refinement of the IAA-induced photoreceptor degeneration model.

Hair Testosterone and Cortisol Concentrations in Pre- and Post-Rut Roe Deer Bucks: Correlations with Blood Levels and Testicular Morphometric Parameters.

The roe deer is a seasonally breeding species with a reproductive cycle regulated by endogenous rhythms and photoperiod-sensitivity. Sexually mature bucks show hormonal and testicular activation during the reproductive season, with a peak in the rut period, and following gradual involution. Hair is a good matrix for non-invasive endocrinological analyses that provide long-term information without being influenced by the hormones’ pulsating release patterns in blood. The aim of the work was to quantify hair concentrations of testosterone and cortisol in wild roe deer bucks hunted during the pre- and post-rut period, using a radioimmunoassay methodology, and to look for differences between the two periods. The secondary objective was the evaluation of possible correlations of such hair concentrations with blood and morphometric parameters of the testes. Both hormones showed statistical differences, with opposing trends, when comparing the two periods: testosterone increased while cortisol decreased. The correlation analysis was in agreement with existing literature regarding metabolism/actions of these hormones and testicular morphometric parameters. This study represents the first report of the use of radioimmunoassay techniques to quantify testosterone and cortisol in roe deer hair, and may provide interesting insights into their reproductive physiology.