In the present study, a mixture of ammonium-bicarbonate (NH(4)HCO(3)) and sodium-chloride (NaCl) particles was used as a porogen additive to fabricate highly macroporous biodegradable poly(lactic-co-glycolic acid) (PLGA) scaffolds. A two-step salt-leaching process was performed after the sample had become semisolidified. Compared to the standard solvent-casting/particulate-leaching (SC/PL) technique, the processing time of this approach was significantly shorter: Instead of several days, only half a day was required. In addition, the polymer/salts/solvent mixture can be easily handled and molded into scaffolds of any specific shape-for example, thin sheet, cylindrical, or bone-shaped-for special applications in tissue engineering. Our results demonstrate that these scaffolds have a highly interconnected open-pore structure as well as greater mechanical properties than those made using the standard SC/PL technique. Primary rat osteoblasts seeded into the scaffolds exhibited good seeding efficiency. The method presented here is a promising approach for fabricating scaffolds for tissue engineering applications.

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Soft tissue adhesives made from natural hydrogel are attractive in clinical applications due to their excellent properties, such as high water content, good biocompatibility, low immune, good biodegradability. Hydrogels derived from natural polysaccharides and proteins are ideal components for soft tissue adhesive since they resemble the extracellular matrices of the tissue composed of various sugar and amino acids-based macromolecules. In this paper, a series of novel tissue adhesives mixed by aldehyde sodium alginate (ASA) with amino gelatin (AG) were developed and characterized. The effect of aldehyde content in ASA and amino group content in AG on the properties of ASA/AG cross-linked hydrogel was measured. The results showed the gelling time, swelling behavior and the bonding strength of the hydrogel can be tuned by varying the content of aldehyde groups in ASA and the content of amino groups in AG. The gelation time could be controlled within 4-18 min. When the aldehyde content of ASA is 75.24% and the amino content of AG is 0.61 mmol/g, the hydrogel almost has the adhesive strength equal to the commercially available adhesive fibrin glue. So, this tunable ASA/AG hydrogels in this study could be a promising candidate as soft tissue adhesive and have a wide range of biomedical applications.

Fanconi anemia (FA) is a rare genetic disorder associated with bone-marrow failure, genome instability and cancer predisposition. Recently, we and others have demonstrated dysfunctional mitochondria with morphological alterations in FA cells accompanied by high reactive oxygen species (ROS) levels. Mitochondrial morphology is regulated by continuous fusion and fission events and the misbalance between these two is often accompanied by autophagy. Here, we provide evidence of impaired autophagy in FA. We demonstrate that FA cells have increased number of autophagic (presumably mitophagic) events and accumulate dysfunctional mitochondria due to an impaired ability to degrade them. Moreover, mitochondrial fission accompanied by oxidative stress (OS) is a prerequisite condition for mitophagy in FA and blocking this pathway may release autophagic machinery to clear dysfunctional mitochondria.

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