Diabetic Pedal Osteomyelitis and Its Treatment

Vidyaalakshmi Venkatesan,Jayakumar Rangasamy 전남대학교 의과학연구소 2023 전남의대학술지 Vol.59 No.2

Diabetes is a fast-growing chronic metabolic disorder that is widely associated with foot ulcers. The major challenge among these ulcers is wound infections, altered inflammatory responses, and a lack of angiogenesis that can complicate limb amputation. The foot, because of its architecture, becomes the part most prone to complications and the infection rate is higher mainly between the toes due to the humid nature. Therefore, the infection rate is significantly higher. Wound healing in diabetes is a dynamic process usually delayed due to poor immune function. Diabetes-related pedal neuropathy and perfusion disturbances can lead to a loss of sensation in the foot. This neuropathy can further be a risk factor for ulcer development due to repetitive mechanical stress that later might get infected by the invasion of microorganisms extending to the bone and causing an infection called pedal osteomyelitis. This review details the pathophysiology, the biomaterials aiding in the infection cure and regeneration of bone along with their limitations, as well as their future prospects.

NANO CURCUMIN INCORPORATED ARGININE-CHITOSAN HYDROGEL FOR ENHANCED ANGIOGENESIS

Wook SUN,Annapoorna MOHANDAS,Rangasamy JAYAKUMAR,Nathaniel HWANG 한국생물공학회 2016 한국생물공학회 학술대회 Vol.2016 No.4

A multi-stimuli responsive alginate nanogel for anticancer chemo-photodynamic therapy

Shameer Pillarisetti,Veena Vijayan,Jayakumar Rangasamy,Rizia Bardhan,Saji Uthaman,In-Kyu Park 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.123 No.-

Stimuli-responsive nanosystems enable highly effective targeting and therapeutic functions, includingchemotherapy and photodynamic therapy (PDT). Traditional PDT alone cannot effectively eradicate thetumor burden; combined with chemotherapy, this combination presents a powerful treatment modalityto modulate the tumor microenvironment (TME). Herein, we report a multi-stimulus responsive alginatenanogel that responds to the change in pH and redox potential in the TME. We coupled oxidized alginatewith 4-mercapto phenylboronic acid and pheophorbide-A (a hydrophobic photosensitizer) and conjugatedwith adipic acid dihydrazide to design the nanogels. Further, we encapsulated doxorubicin, a cytotoxicagent, in the nanogel to enable chemotherapy. The alginate nanogel exhibited the pH-sensitiverelease of both pheophorbide-Aand doxorubicin and simultaneously reduced the redox potential thatenhanced PDT by increasing reactive oxygen species production. Our results demonstrate that themulti-stimuli responsive alginate nanogel enhances toxicity in breast cancer and melanoma.

Human Adipose Tissue Derivatives as a Potent Native Biomaterial for Tissue Regenerative Therapies

Siva Sankari Sharath,Janarthanan Ramu,Shantikumar Vasudevan Nair,Subramaniya Iyer,Ullas Mony,Jayakumar Rangasamy 한국조직공학과 재생의학회 2020 조직공학과 재생의학 Vol.17 No.2

Background: Human adipose tissue is a great source of translatable biomaterials owing to its ease of availability and simple processing. Reusing discardable adipose tissue for tissue regeneration helps in mimicking the exact native microenvironment of tissue. Over the past 10 years, extraction, processing, tuning and fabrication of adipose tissue have grabbed the attention owing to their native therapeutic and regenerative potential. The present work gives the overview of next generation biomaterials derived from human adipose tissue and their development with clinical relevance. Methods: Around 300 articles have been reviewed to widen the knowledge on the isolation, characterization techniques and medical applications of human adipose tissue and its derivatives from bench to bedside. The prospective applications of adipose tissue derivatives like autologous fat graft, stromal vascular fraction, stem cells, preadipocyte, adipokines and extracellular matrix, their behavioural mechanism, rational property of providing native bioenvironment, circumventing their translational abilities, recent advances in featuring them clinically have been reviewed extensively to reveal the dormant side of human adipose tissue. Results: Basic understanding about the molecular and structural aspect of human adipose tissue is necessary to employ it constructively. This review has nailed the productive usage of human adipose tissue, in a stepwise manner from exploring the methods of extracting derivatives, concerns during processing and its formulations to turning them into functional biomaterials. Their performance as functional biomaterials for skin regeneration, wound healing, soft tissue defects, stem cell and other regenerative therapies under in vitro and in vivo conditions emphasizes the translational efficiency of adipose tissue derivatives. Conclusion: In the recent years, research interest has inclination towards constructive tissue engineering and regenerative therapies. Unravelling the maximum utilization of human adipose tissue derivatives paves a way for improving existing tissue regeneration and cellular based therapies and other biomedical applications.

Trends in mechanobiology guided tissue engineering and tools to study cell-substrate interactions: A brief review

Arun Kumar Rajendran,Deepthi Sankar,Sivashanmugam Amirthalingam,김환,Jayakumar Rangasamy,Nathaniel S. Hwang 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Sensing the mechanical properties of the substrates or the matrix by the cells and the tissues, the subsequent downstream responses at the cellular, nuclear and epigenetic levels and the outcomes are beginning to get unraveled more recently. There have been various instances where researchers have established the underlying connection between the cellular mechanosignalling pathways and cellular physiology, cellular differentiation, and also tissue pathology. It has been now accepted that mechanosignalling, alone or in combination with classical pathways, could play a significant role in fate determination, development, and organization of cells and tissues. Furthermore, as mechanobiology is gaining traction, so do the various techniques to ponder and gain insights into the still unraveled pathways. This review would briefly discuss some of the interesting works wherein it has been shown that specific alteration of the mechanical properties of the substrates would lead to fate determination of stem cells into various differentiated cells such as osteoblasts, adipocytes, tenocytes, cardiomyocytes, and neurons, and how these properties are being utilized for the development of organoids. This review would also cover various techniques that have been developed and employed to explore the effects of mechanosignalling, including imaging of mechanosensing proteins, atomic force microscopy (AFM), quartz crystal microbalance with dissipation measurements (QCMD), traction force microscopy (TFM), microdevice arrays, Spatio-temporal image analysis, optical tweezer force measurements, mechanoscanning ion conductance microscopy (mSICM), acoustofluidic interferometric device (AID) and so forth. This review would provide insights to the researchers who work on exploiting various mechanical properties of substrates to control the cellular and tissue functions for tissue engineering and regenerative applications, and also will shed light on the advancements of various techniques that could be utilized to unravel the unknown in the field of cellular mechanobiology.

In vivo evaluation of cetuximab-conjugated poly(γ-glutamic acid)-docetaxel nanomedicines in EGFR-overexpressing gastric cancer xenografts

Sreeranganathan, Maya,Uthaman, Saji,Sarmento, Bruno,Mohan, Chethampadi Gopi,Park, In-Kyu,Jayakumar, Rangasamy DOVE MEDICAL PRESS 2017 INTERNATIONAL JOURNAL OF NANOMEDICINE Vol.12 No.-

<P>Epidermal growth factor receptor (EGFR), upregulated in gastric cancer patients, is an oncogene of interest in the development of targeted cancer nanomedicines. This study demonstrates in silico modeling of monoclonal antibody cetuximab (CET MAb)-conjugated docetaxel (DOCT)-loaded poly(γ-glutamic acid) (γ-PGA) nanoparticles (Nps) and evaluates the in vitro/in vivo effects on EGFR-overexpressing gastric cancer cells (MKN-28). Nontargeted DOCT-γ-PGA Nps (NT Nps: 110±40 nm) and targeted CET MAb-DOCT-γ-PGA Nps (T Nps: 200±20 nm) were prepared using ionic gelation followed by 1-Ethyl-3-(3-dimethyl aminopropyl)carbodiimide–N-Hydoxysuccinimide (EDC–NSH) chemistry. Increased uptake correlated with enhanced cytotoxicity induced by targeted Nps to EGFR +ve MKN-28 compared with nontargeted Nps as evident from MTT and flow cytometric assays. Nanoformulated DOCT showed a superior pharmacokinetic profile to that of free DOCT in Swiss albino mice, indicating the possibility of improved therapeutic effect in the disease model. Qualitative in vivo imaging showed early and enhanced tumor targeted accumulation of CET MAb-DOCT-γ-PGA Nps in EGFR +ve MKN-28–based gastric cancer xenograft, which exhibited efficient arrest of tumor growth compared with nontargeted Nps and free DOCT. Thus, actively targeted CET MAb-DOCT-γ-PGA Nps could be developed as a substitute to conventional nonspecific chemotherapy, and hence could become a feasible strategy for cancer therapy for EGFR-overexpressing gastric tumors.</P>

Biomimetic Materials and Fabrication Approaches for Bone Tissue Engineering

Kim, Hwan D.,Amirthalingam, Sivashanmugam,Kim, Seunghyun L.,Lee, Seunghun S.,Rangasamy, Jayakumar,Hwang, Nathaniel S. Wiley (John WileySons) 2017 Advanced healthcare materials Vol.6 No.23