A Gelatin-Based Biomimetic Scaffold Promoting Osteogenic Differentiation of Adipose-Derived Mesenchymal Stem Cells.

Background: In bone tissue engineering segment, numerous approaches have been investigated to address critically sized bone defects via 3D scaffolds, as the amount of autologous bone grafts are limited, accompanied with complications on harvesting. Moreover, the use of bone-marrow-derived stem cells is also a limiting factor owing to the invasive procedures involved and the low yield of stem cells. Hence, research is ongoing on the search for an ideal bone graft system promoting bone growth and regeneration. Purpose of the Study: This study aims to develop a unique platform for tissue development via stem cell differentiation towards an osteogenic phenotype providing optimum biological cues for cell adhesion, differentiation and proliferation using biomimetic gelatin-based scaffolds. The use of adipose-derived mesenchymal stem cells in this study also offers an ideal approach for the development of an autologous bone graft. Methods: A gelatin-vinyl acetate-based 3D scaffold system incorporating Bioglass was developed and the osteogenic differentiation of adipose-derived mesenchymal stem cells (ADMSCs) on the highly porous freeze-dried gelatin-vinyl acetate/ Bioglass scaffold (GB) system was analyzed. The physicochemical properties, cell proliferation and viability were investigated by seeding rat adipose tissue-derived mesenchymal stem cells (ADSCs) onto the scaffolds. The osteogenic differentiation potential of the ADMSC seeded GeVAc/bioglass system was assessed using calcium deposition assay and bone-related protein and genes and comparing with the 3D Gelatin vinyl acetate coppolymer (GeVAc) constructs. Results and Conclusion: According to the findings, the 3D porous GeVAc/bioglass scaffold can be considered as a promising matrix for bone tissue regeneration and the 3D architecture supports the differentiation of the ADMSCs into osteoblast cells and enhances the production of mineralized bone matrix.

Anti-inflammatory and wound healing properties of lactic acid bacteria and its peptides.

Recent studies manifest an increase of inflammatory diseases at an alarming rate due to gut microbiota dysbiosis, genetic and other environmental factors. Lactic acid bacteria (LAB) are known for their antimicrobial properties and their extensive applications in food and pharmaceutical industries. Cyclic peptides are receiving increased attention due to their remarkable stability to withstand variations in temperature and pH. LAB produces anti-inflammatory that can inhibit lipopolysaccharide-induced production of proinflammatory cytokines in macrophages. The structural backbones of cyclic peptides offer a promising approach for the treatment of chronic inflammatory conditions. The current review aims to present the overview of anti-inflammatory and wound healing properties of LAB-derived cyclic peptides.

Colloidal Photonic Crystal-Enhanced Fluorescence of Gold Nanoclusters: A Highly Sensitive Solid-state Fluorescent Probe for Creatinine.

Gold nanoclusters (AuNCs) are an intensely pursued class of fluorophores with excellent biocompatibility, high water solubility, and ease of further conjugation. However, their low quantum yield limits their applications, such as ultra-sensitive chemical or molecular sensing. To address this problem, various strategies have been adopted for augmenting their fluorescence intensity. Herein, we report a facile and scalable approach for the fluorescence enhancement of bovine serum albumin (BSA) capped AuNCs (BSA-AuNCs) using periodic, close-packed polystyrene colloidal photonic crystals (CPCs). The slow photon effect at the bandgap edges is utilized for the increased light-matter interactions and thereby enhancing the fluorescence intensity of the BSA-AuNCs. Compared to the planar polystyrene control sample, the CPC film yielded a 14-fold enhancement in fluorescence intensity. Further, we demonstrated the as-prepared BSA-AuNCs-CPC as a solid-state platform for the highly sensitive and selective fluorescence turn-off detection of creatinine at nanomolar level.

Thyrotoxic Periodic Paralysis: An Unusual Cause of Quadriparesis.

Thyrotoxic periodic paralysis (TPP) is an uncommon disorder characterized by acute onset of hypokalemia (serum potassium level less than 3.5 mmol/L) and paralysis secondary to thyrotoxicosis. Patients can present with TPP as the first clinical manifestation of thyrotoxicosis. In patients presenting with acute episodes, the presence of hypokalemia and elevated levels of thyroid hormones with low thyroid-stimulating hormone levels (less than 0.35 µIU/mL) are important diagnostic clues. We report one case of TPP in which the acute onset of paralysis was the first clinical presentation of underlying thyrotoxicosis. After treatment with propranolol and carbimazole, the patient became symptom-free and euthyroid.

Extracranial Internal Carotid Aneurysm Manifesting With Tinnitus: A Rare Presentation.

A 19-year-old male presented with a history of pulsatile tinnitus on the left side after he underwent drainage for a tonsillar swelling. He had noticed a painless neck swelling one month ago that was associated with difficulty in swallowing. His physician had made a diagnosis of peritonsillar abscess, and drainage had been performed. After the procedure, the swelling had progressed further, leading to drooling of saliva and disabling tinnitus. When he presented to the emergency, local examination revealed a pulsatile neck swelling with peritonsillar mass. CT angiography/digital subtraction angiography (DSA) of the neck and brain revealed a large aneurysm of the distal cervical segment of the left internal carotid artery (ICA). The patient successfully underwent an urgent open repair. This case highlights the importance of a thorough history and examination in identifying a rare cause of pulsatile tinnitus. A stepwise approach to determine the reason behind tinnitus revealed an underlying ICA aneurysm of the extracranial segment.

Cyclic peptide production from lactic acid bacteria (LAB) and their diverse applications.

In recent years, cyclic peptides gave gained increasing attention owing to their pH tolerance, heat stability and resistance to enzymatic actions. The increasing outbreaks of antibiotic resistant pathogens and food spoilage have prompted researchers to search for new approaches to combat them. The increasing number of reports on novel cyclic peptides from lactic acid bacteria (LAB) is considered as a breakthrough due to their potential applications. Although an extensive investigation is required to understand the mechanism of action and range of applications, LAB cyclic peptides can be considered as potential substitutes for commercially available antibiotics and bio preservatives. This review summarizes the current updates of LAB cyclic peptides with emphasis on their structure, mode of action and applications. Recent trends in cyclic peptide applications are also discussed.