组织科学与工程学报

The design and fabrication of bioresorbable polymeric graft substitutes and porous scaffolds for regenerative medicine are challenged by the complexities in structure and composition found in native tissues. The mimicking of complex gradations found in native tissues requires correspondingly complex gradations in bone graft substitutes and tissue engineering scaffolds. Extrusion based processing methods offer significant advantages for the fabrication of scaffolds and polymeric graft substitutes functionally-graded in various directions for porosity, composition as well as distributions of other tissue relevant properties.

At present worldwide there are more than 350 clinical trials involving human Mesenchmal Stem/Stromal Cells (MSC). These trials involve the regenerative potential of hundreds of diseases or syndromes. However, only approximately 10% of the conditions explored are investigated in more than 10 clinical trials, while most of the maladies are investigated in 3 trials or less worldwide. In addition, the MSCs used in pre-clinical studies versus those used in the clinical trials are produced by variable procedures. In the majority of conditions under investigation the outcome of the studies is therefore cumbersome to evaluate. Standardizing in vitro cell culture procedures for definition and production of MSC could help to facilitate the evaluation of these cells in the clinical context, especially in those clinical trials that are minimally addressed. We advocate consistent Good Manufacturing Practice (GMP) compliant procedures for production of MSC in the context of all pre-clinical experiments, especially since clinically, GMP-compliant production of cells is the standard anyway.

This study aimed to characterize the different parts of Carica papaya (ripe and unripe papaya, leaves and seed), through their proximate composition, total antioxidant activity, and in vitro antiproliferative activities. Both macronutrients and micronutrients were determined using standard AOAC methods of analysis, while vitamin analyses were determined by High Performance Liquid Chromatography (HPLC). Results showed that the ripe papaya had the highest antioxidant activity (84.04%) followed by unripe papaya (81.35%), leaves (78.03%) and the least was seed (75.35%).The phenolic content was in the order of leaves>unripe papaya>ripe papaya>seed. HPLC analysis showed that papaya leaves exhibited the highest ascorbic acid and β-carotene content (85.60 and 3.86 mg/100 g respectively), while the seeds had the highest Vitamin E content (4.09 mg/100 g). Results obtained from cytotoxic activities showed that MCF-7 (hormone dependent breast cancer) and MDA-MB-231 (non-hormone dependent breast cancer) cell cultures were significantly inhibited by the extract. The antioxidant and antiproliferative activities of different parts papaya extracts indicate that the consumption of the whole fruit, ripe and unripe papaya, leaves and the seed supplies the important quantities of numerous necessary nutrients for human diet which includes vitamins A, C and E.

This study presents a novel methodology for fabrication of tubular vascular tissue mimics by an automated factory using thermoresponsive polymers which have temperature-induced reversible phase transition characteristics; Poly(N-Isopropylacrylamide)-Grafted Gelatin (PNIPAM-gelatin), PNIPAM and gelatin. The custom-designed factory consists of a moving tray, a roller unit driven by rack-and-pinion mechanics, and a local temperature-control unit. PNIPAM-gelatin serves as the matrix, providing temperature-dependent adhesion and detachment of cell sheets. We describe two prototypes of vascular tissue mimics: a tubular medial tissue mimic composed of randomly oriented Smooth Muscle Cells (SMCs), and a hierarchically structured vascular tissue mimic (intimal/medical tissue mimics) composed of longitudinally oriented Endothelial Cells (ECs) on the luminal surface and circumferentially oriented multilayered SMCs in the outer layer. We observed these prototypes under electron microscopes and a Confocal Laser-Scanning Microscope (CLSM). An advanced model of our prototype factory would have the potential to produce high-quality on-demand vascular grafts without incorporating any foreign materials.

In vitro embryo-production procedures developed for sheep have tremendously been improved from decades,
but many factors influencing their efficiency still need to be investigated. The overall of this study showed the
production of the sheep embryos till blastocyst stage from the ovaries of the slaughtered ewes for IVM, IVF of the
oocytes and then IVC in the complex culture media like TCM-199, TCM-199-, TCM-199+ and CR1aa. The morula
yield was significantly higher in the wheat peptone and BSA supplemented group. The nuclear maturation rates of
ovine oocytes matured in FBS (69.15 ± 1.07) group was more compared to BSA (56.47 ± 0.73) and wheat peptone
(35.26 ± 0.79). The nuclear maturation of oocytes was significantly higher in the FBS group when compared to BSA
and wheat peptone supplemented groups. The lowest maturation rate was observed in wheat peptone supplemented
group. The development rates in 2, 4, 8, 16 and morula stages of ovine embryos produced from BSA group were high
(74.22 ± 2.56, 60.93 ± 2.55, 42.97 ± 2.20 and 24.21 ± 1.28) compared to FBS group (73.58 ± 2.92, 58.77 ± 2.01,
41.22 ± 1.68 and 20.17 ± 0.76) and wheat peptone (72.89 ± 1.09, 57.01 ± 0.76, 42.05 ± 0.36 and 24.29 ± 0.55). The
cleavage, morula and blastocyst percent in CR1aa was found significantly high compared with TCM- 199, TCM-199-
and TCM-199+. The cleavage, morula and blastocyst percent in L-Ascorbic acid at 100 μM with CR1aa is found more
significant compared with other compositions used in the experimentation.

The aim of this study was to performed to characterize three different cold isostatic pressed Y-TZP, one being
controlled manufacturing, concerning its biocompatibility in contact with cultured human gingival fibroblasts and its
crystalline structure by Micro-Raman Spectroscopy.