3D Bio-printing For Skin Tissue Regeneration: Hopes and Hurdles

Abstract:

For many years, discovering the appropriate methods for the treatment of skin irritation has been challenging for specialists and researchers. Bio-printing can be extensively applied to address the demand for proper skin substitutes to improve skin damage. Nowadays, to make more effective bio-mimicking of natural skin, many research teams have developed cell-seeded bio-inks for bioprinting of skin substitutes. These loaded cells can be single or co-cultured in these structures. The present review gives a comprehensive overview of the methods, substantial parameters of skin bioprinting, examples of in vitro and in vivo studies, and current advances and challenges for skin tissue engineering.

In Vitro Development of Mouse Preantral Follicle with Using Amniotic Membrane Extract-Loaded Hydrogels

An artificial ovary based on the alginate (ALG) hydrogel has been widely implemented to preserve prepubertal female fertility. However, this platform is not fully capable of successful an ovary microenvironment simulation for follicle development, holding great potential for its improvement. Therefore, this experimental study aimed to evaluate the effect of an amniotic membrane extract (AME) -loaded hydrogel on the mouse preantral follicles in vitro development. In order to have better follicle development, first, the impact of different concentrations of follicle-stimulating hormone (FSH) was evaluated on the mouse preantral follicles encapsulated in ALG. Later, the appropriate dose was adjusted for the follicles encapsulated in the ALG-AME hydrogel. Results demonstrated that 100 mIU/ml FSH showed a significant follicle survival rate compared with 10 mIU/ml FSH (P=0.005). According to MTT assay finding, the rate of weight loss, and rheology evaluations, ALG containing 1 mg/ml AME was identified as an optimal sample of follicle culture instead of other AME concentrations. Follicle diameter significantly increased in the ALG-AME 1 hydrogel compared with the ALG control group without AME (P=0.027). The storage modulus of ALG-AME 1 was 773 Pa and retained the follicle morphology for 13 days. No statistically substantial difference was seen in survival, antrum cavity formation, and competent oocyte in terms of the normal chromosomal arrangement and meiotic spindle rate in comparison with the control group. It can be concluded that ALG-AME 1 could not significantly impact the mouse preantral follicle.

First Proton-Induced Cross Sections on a Stored Rare Ion Beam: Measurement of ^{118}Te(p,γ) for Explosive Nucleosynthesis

We present the first nuclear cross-section measurements of (p,γ) and (p,n) reactions on ^{118}Te at energies relevant for the γ-process nucleosynthesis. Absolute cross-section values for center-of-mass energies of 6, 7 and 10 MeV are provided, together with a theoretical extrapolation to the Gamow window. This experiment marks the first time that direct proton-induced reactions have been measured on a radioactive ion beam at the Experimental Storage Ring (ESR) at GSI, Darmstadt. This paves the way for a large variety of measurements, delivering new constraints for explosive nucleosynthesis and for physics beyond nuclear stability.

Communication : A SIMPLE METHOD FOR THE DETERMINATIONOF CHLORPROMAZINE IN PHARMACEUTICALPREPARATIONS AND BLOOD SERUM

A simple rapid and accurate method is described for the analysis of chlorpromazine. The method utilises reverse phase HPLC with a methanol: water system 50:50 as mobile phase and UV detection. The same has been successfully applied on locally available pharmaceutical preparations and in blood serum after drug administration.

Production and separation of positron emitters for hadron therapy at FRS-Cave M

The FRagment Separator FRS at GSI is a versatile spectrometer and separator for experiments with relativistic in-flight separated short-lived exotic beams. One branch of the FRS is connected to the target hall where the bio-medical cave (Cave M) is located. Recently a joint activity between the experimental groups of the FRS and the biophysics at the GSI and Department of physics at LMU was started to perform biomedical experiments relevant for hadron therapy with positron emitting carbon and oxygen beams. This paper presents the new ion-optical mode and commissioning results of the FRS-Cave M branch where positron emitting ¹⁵O-ions were provided to the medical cave for the first time. An overall conversion efficiency of 2.9±0.2×10^{-4 15}O fragments per primary ¹⁶O ion accelerated in the synchrotron SIS18 was reached.

Trapezius or facial muscles: Which one is more suitable for the measurement of stress using sEMG signals?

A number of techniques have been reported to detect mental stress. Surface Electromyography (sEMG) has also been used to measure stress by acquiring the signals from various sites of the human body, however, consensus need to be established to determine the best possible site to harvest stress related information. In this study, work related mental stress using sEMG signals acquired from trapezius muscle and facial muscles were compared. BIOPAC signal acquisition system was used to acquire sEMG signals simultaneously from both trapezius and facial muscles from forty five (45) healthy volunteers. Stress was induced using different standard methods in a controlled environment. Statistical significant difference was found between the stress and rest levels of sEMG signals. The statistical test also showed that the upper trapezius muscle was a better stress detection site as compared to facial muscles.Clinical Relevance- Optimized stress detection can help in the prevention of the possible stress related physical disorders.