Assessment and Modeling of Plasmonic Photothermal Therapy Delivered via a Fiberoptic Microneedle Device Ex Vivo

Plasmonic photothermal therapy (PPTT) has potential as a superior treatment method for pancreatic cancer, a disease with high mortality partially attributable to the currently non-selective treatment options. PPTT utilizes gold nanoparticles infused into a targeted tissue volume and exposed to a specific light wavelength to induce selective hyperthermia. The current study focuses on developing this approach within an ex vivo porcine pancreas model via an innovative fiberoptic microneedle device (FMD) for co-delivering light and gold nanoparticles. The effects of laser wavelengths (808 vs. 1064 nm), irradiances (20–50 mW·mm−2), and gold nanorod (GNR) concentrations (0.1–3 nM) on tissue temperature profiles were evaluated to assess and control hyperthermic generation. The GNRs had a peak absorbance at ~800 nm. Results showed that, at 808 nm, photon absorption and subsequent heat generation within tissue without GNRs was 65% less than 1064 nm. The combination of GNRs and 808 nm resulted in a 200% higher temperature rise than the 1064 nm under similar conditions. A computational model was developed to predict the temperature shift and was validated against experimental results with a deviation of <5%. These results show promise for both a predictive model and spatially selective, tunable treatment modality for pancreatic cancer.

The Activation Energies and Optimum Temperatures of Olive Oil Hydrolysis By Lipase Porcine Pancreas

Lipase activity is a perfect indicator for the monitoring of processes of bioremediation of degraded soils. Lipase is also used in the processes of oil hydrolysis in wastewater treatment. To be able to predict and model processes with used lipase in environmental operations, knowledge of the kinetic parameters of the process are required. The paper presents the determined values of activation energies and optimum temperatures for porcine pancreas lipase. The parameters were estimated based on the literature of the activity curves vs. temperature for hydrolysis of olive oil by lipase. It was noticed that concentration of gum arabic added as an emulsifier during lipase activity measurements influences on the obtained values of determined parameters. A mathematical model describing the effect of temperature on porcine pancreas lipase activity was used. Based on the comparison analysis, the optimum temperature Topt were obtained in the range from 313.30 ±0.56 to 319.62 ±0.96 K, activation energies Ea were from 51 ±10 to 82.6 ±9.9 kJ/mol, and values of deactivation energies Ed were in the range from 122.7 ±4.0 to 150.9 ±5.8 kJ/mol.

Saline extraction as a method of obtaining a mixture of biologically active compounds of protein nature from a porcine pancreas

A relevant solution to the problem of processing meat industry waste in Russia is to obtain useful biologically active compounds from abundant organs. The aim of this study was to examine the effectiveness of the saline extraction as a method for extracting a mixture of promising biologically active compounds from the porcine pancreas, as well as to determine the optimal time for the process. The study consisted of extraction of the porcine pancreas with 0,9% sodium chloride solution for 5 h 30 min with further determination of the total protein concentration and proteomic profile of the samples taken throughout the process. Based on the analysis of the dependence of the total protein content in the extractant on time, the optimal extraction time was determined to be 135–150 minutes. When studying the results of electrophoresis and the data of their processing, the optimal extraction time for the targeted isolation of the low-molecular fraction of compounds was also determined to be 90 min. At the same time, 13 protein bands with a molecular weight of 52 kDa and below were found on the electropherograms. Saline should be considered applicable for obtaining extracts rich in biologically active substances, incl. hormones, enzymes and other physiologically active compounds.

Determination of Activation Energies and the Optimum Temperatures of Hydrolysis of Starch by α-Amylase from Porcine Pancreas

The present paper reports the determination of the activation energies and the optimum temperatures of starch hydrolysis by porcine pancreas α-amylase. The parameters were estimated based on the literature data on the activity curves versus temperature for starch hydrolysis by α-amylase from porcine pancreas. It was assumed that both the hydrolysis reaction process and the deactivation process of α-amylase were first-order reactions by the enzyme concentration. A mathematical model describing the effect of temperature on porcine pancreas α-amylase activity was used. The determine deactivation energies Ea were from 19.82 ± 7.22 kJ/mol to 128.80 ± 9.27 kJ/mol, the obtained optimum temperatures Topt were in the range from 311.06 ± 1.10 K to 326.52 ± 1.75 K. In turn, the values of deactivation energies Ed has been noted in the range from 123.57 ± 14.17 kJ/mol to 209.37 ± 5.17 kJ/mol. The present study is related to the starch hydrolysis by α-amylase. In the industry, the obtained results the values Ea, Ed, Topt can be used to design and optimize starch hydrolysis by α-amylase porcine pancreas. The obtained results might also find application in research on the pharmaceutical preparations used to treat pancreatic insufficiency or prognosis of pancreatic cancer.

A novel approach to trypsin inhibition by flavonoids

Trypsin is a key protease related to digestion and absorption of proteins, which its inhibition must be studied when natural compounds, such as flavonoids, are used as part of alternative treatments for obesity and diabetes mellitus type 2, since trypsin and together with other pancreatic enzymes worked at small intestine. Considering that flavonoids are good lipase and amylase inhibitors, trypsin-flavonoids interactions were analyzed through UV-Vis, intrinsic and extrinsic fluorescence spectroscopies, circular dichroism, and molecular docking. The interaction between porcine pancreas trypsin and five flavonoids: hesperetin (HES), luteolin (LUT), quercetin (QUE), catechin (CAT), and rutin (RUT) was evaluated. Most of them exhibited a mixed-type mode. LUT was the best trypsin inhibitor (e.g., lower IC50, 45.20±1.00 µM). All flavonoids-trypsin complexes showed static quenching, and QUE and LUT exhibited higher affinity (higher Ka values, 0.90±0.10 and 1.60±0.20·10-1 mM-1, respectively). Hydrophobic interactions between trypsin and flavonoids were predominant.

Impact of Porcine Pancreas Decellularization Conditions on the Quality of Obtained dECM

Due to the limited number of organ donors, 3D printing of organs is a promising technique. Tissue engineering is increasingly using xenogeneic material for this purpose. This study was aimed at assessing the safety of decellularized porcine pancreas, together with the analysis of the risk of an undesirable immune response. We tested eight variants of the decellularization process. We determined the following impacts: rinsing agents (PBS/NH3·H2O), temperature conditions (4 °C/24 °C), and the grinding method of native material (ground/cut). To assess the quality of the extracellular matrix after the completed decellularization process, analyses of the following were performed: DNA concentration, fat content, microscopic evaluation, proteolysis, material cytotoxicity, and most importantly, the Triton X-100 content. Our analyses showed that we obtained a product with an extremely low detergent content with negligible residual DNA content. The obtained results confirmed the performed histological and immuno-fluorescence staining. Moreover, the TEM microscopic analysis proved that the correct collagen structure was preserved after the decellularization process. Based on the obtained results, we chose the most favorable variant in terms of quality and biology. The method we chose is an effective and safe method that gives a chance for the development of transplant and regenerative medicine.