Development and Optimization of Freeze-Dried Eye Drops Derived from Plasma Rich in Growth Factors Technology

Purpose: To investigate whether plasma rich in growth factors (PRGF) eye drops maintain their biological potential after a freeze drying process. The addition of a lyopro-tectant like trehalose was also evaluated. Methods: Blood from three healthy donors was collected to obtain eye drops by PRGF technology. The resultant eye drops were divided in four groups: PRGF, freeze-dried PRGF (PRGF lyo), and PRGF lyophilized mixed with 2,5% trehalose (PRGF lyo+2.5T) or 5% trehalose (PRGF lyof+5T). Chemical and biological characteristics were evaluated. Photorefractive keratectomy was performed on C57BL/6 mice which were divided in three treatment groups: control, PRGF, and PRGF lyo. Corneal wound healing and haze formationwere evaluated macroscopically. Eyeswere collected at 1, 2, 3, and 7 days after surgery, and were processed for histologic studies. Results: The pH values of PRGF samples increased significantly after the lyophilization process. Osmolarity levels increased significantly in PRGF samplesmixed with trehalose in comparison with PRGF samples without protectants. The freeze drying process maintained growth factors levels as well as the biological properties of PRGF eye drops even without the use of lyoprotectants. PRGF lyo treatment significantly decreased the re-epithelialization time and haze formation in photorefractive keratectomy-treated corneas regarding PRGF and control groups. Furthermore, the PRGF lyo group significantly decreased the number of smooth muscle actin-positive cells in comparison with the control group at each time of the study and at days 2 and 3 in the PRGF group. Conclusions: The freeze drying process preserves the protein and growth factor content as well as the biological properties of PRGF eye drops, even without the use of protectants. Freeze-dried PRGF eye drops accelerate corneal tissue regeneration after photorefractive keratectomy in comparison with the control group. Translational Relevance: Our study shows the feasibility to preserve the biological capability of PRGF eye drops as freeze-dried formulation, avoiding the addition of protectants.This study received funding from the Basque Country Government, within the Elkartek program, phase I. Support program for collaborative research in strategic area, within the project named SINET (reference KK-2018/00048

Differential profile of protein expression on human keratocytes treated with autologous serum and plasma rich in growth factors (PRGF)

Purpose The main objective of this study is to compare the protein expression of human keratocytes treated with Plasma rich in growth factors (PRGF) or autologous serum (AS) and previously induced to myofibroblast by TGF-beta 1 treatment. Methods Blood from healthy donor was collected and processed to obtain AS and PRGF eye drops. Blood derivates were aliquoted and stored at-80 degrees C until use. Keratocyte cells were pretreated for 60 minutes with 2.5 ng/ml TGF-beta 1. After that, cells were treated with PRGF, AS or with TGF-beta 1 (control). To characterize the proteins deregulated after PRGF and AS treatment, a proteomic approach that combines 1D-SDS-PAGE approach followed by LC-MS/MS was carried out. Results Results show a catalogue of key proteins in close contact with a myofibroblastic differentiated phenotype in AS treated-cells, whereas PRGF-treated cells show attenuation on this phenotype. The number of proteins downregulated after PRGF treatment or upregulated in AS-treated cells suggest a close relationship between AS-treated cells and cytoskeletal functions. On the other hand, proteins upregulated after PRGF-treatment or downregulated in AS-treated cells reveal a greater association with processes such as protein synthesis, proliferation and cellular motility. Conclusion This proteomic analysis helps to understand the molecular events underlying AS and PRGF-driven tissue regeneration processes, providing new evidence that comes along with the modulation of TGF-beta 1 activity and the reversion of the myofibroblastic phenotype by PRGF.This study was fully supported by BTI Biotechnology Institute, a dental implant company that investigates in the fields of oral implantology and PRGF-Endoret technology. MF and FM received a salary as scientists from BTI Biotechnology Institute. EA is the Scientific Director and president of BTI Biotechnology Institute. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Plasma Rich in Growth Factors Membrane as Coadjuvant Treatment in the Surgery of Ocular Surface Disorders

To evaluate the safety and efficacy of the surgical use of plasma rich in growth factors fibrin membrane (mPRGF) in different ocular surface pathologies.Fifteen patients with different corneal and conjunctival diseases were included in the study. Patients were grouped according to the use of mPRGF as graft (corneal and/or conjunctival) or dressing; they were also grouped according to the surgical subgroup of intervention (persistent corneal ulcer [PCU], keratoplasty, superficial keratectomy, corneal perforation, and pterygium). Best corrected visual acuity, intraocular pressure (IOP), inflammation control time (ICT), mPRGF AT (PRGF membrane absorption time), and the healing time of the epithelial defect (HTED) were evaluated throughout the clinical follow-up time. Safety assessment was also performed reporting all adverse events.mPRGF showed a total closure of the defect in 13 of 15 patients (86.7%) and a partial closure in 2 patients (13.3%). The mean follow-up time was 11.14.2 (4.8-22.8) months, the mean ICT was 2.5 +/- 1.1 (1.0-4.0) months, the mean mPRGF AT was 12.4 +/- 2.0 (10.0-16.0) days, and for the global HTED the mean was 2.9 +/- 1.2 (1-4.8) months. Results showed an improvement in BCVA in all patients, with an overall improvement of 2.9 in Vision Lines. The BCVA significantly improved (P.05) throughout the clinical follow-up time. No adverse events were reported after mPRGF use.The mPRGF is effective and safe as coadjuvant treatment in surgeries related with ocular surface disorders, being an alternative to the use of amniotic membrane. The mPRGF accelerates tissue regeneration after ocular surface surgery thus minimizing inflammation and fibrosis.This study received funding from the Ministry of Economy and Competitiveness of the Spanish Government, within the project denominated SURFEYE (reference RTC-2014-2375-1)

SRF Cavity Simulator For LLRF Algorithms Debugging

The availability of niobium superconducting cavities, either due to a lack of a real cavity or due to the time needed for the experiment set up vacuum, cryogenics, cabling, etc. , is limited, and thus it can block or delay the development of new algorithms such as low level RF control. Hardware in the loop simulations, where an actual cavity is replaced by an electronics system, can help to solve this issue. In this paper we present a Cavity Simulator implemented in a National Instruments PXI equipped with an FPGA module. This module operates with one intermediate frequency input which is IQ demodulated and fed to the electrical cavity s model, where the transmitted and reflected voltages are calculated and IQ modulated to generate two intermediate frequency outputs. Some more advanced features such as mechanical vibration modes driven by Lorentz force detuning or external microphonics have also been implemented. This Cavity Simulator is planned to be connected to an mTCA chassis to close the loop with a LLRF control syste

Virtual SRF Cavity Testing SRF Cavity Support Systems Without the Hassle of Liquid Helium and Klystrons

Setting up and debugging SRF support systems, such as LLRF control, quench detection, microphonics and Lorentz force detuning control, etc., often requires extensive time spent operating the cavities. This results in time consuming and costly operation. Early into the development stages the actual cavity system may not even be available. It is therefore highly desirable to pre evaluate these systems under realistic conditions prior to final testing with the SRF cavities. We devised an FPGA based virtual cavity that takes a regular low level RF input and generates the signals for RF power reflection, transmission and detuning that mimic the response of a real cavity system. As far as the user is concerned, the response is the same as for a real cavity. This black box model includes mechanical modes, Lorentz force detuning, a field depended quality factor, quenches and variable input coupling and is currently being expanded. We present the model and show some applications for operating the quench detection, LLRF and microphonics control for 1.3 GHz bERLinPro cavities. The same system can be used for other cavity types, including normal conducting cavitie

Superconducting Radio frequency Virtual Cavity for Control Algorithms Debugging

Superconducting radio frequency cavities are one of the most important elements in modern particle accel erators as they are used for beam acceleration, bunch manipulation, bunch focusing and defocusing, etc. Nevertheless, the availability of these complex structures prior to their installation in the accelerator is lim ited, either due to a lack of a real cavity or due to the time needed for the experiment set up vacuum, cryogenics, cabling, etc. , and thus it can block or delay the development of new algorithms such as low level RF control, quench detection, etc. In this paper, we present a hardware virtual cavity to be used in hardware in the loop simulations. The system implements a cavity electrical model for the transmitted and re ected voltages and more advanced features such as mechanical vibration modes driven by Lorentz force detuning or external microphonics, hard quenches and Q slope. As viewed from the RF input and output, this virtual cavity acts like a real superconducting radio frequency SRF cavity and can replace such a system in early stage debugging and operation of ancillary control system