Role of Doppler Ultrasound in Assessing the Severity of Peripheral Arterial Diseases of the Lower Limb.

BACKGROUND: Peripheral arterial disease is defined as a clinical disorder in which there is a stenosis or occlusion of the arteries of the limbs. The most common etiology is ischemia due to occlusive disease. The objective of this study is to assess the severity of lower-limb peripheral arterial diseases based on various Doppler parameters. METHODS: This descriptive cross-sectional study comprised 55 patients with clinical signs and symptoms of lower-limb peripheral arterial disease. Both inpatients and outpatients attending the authors' institute were taken up for the study. In this study, Doppler sonography was performed using 3-12 MHz linear array and 1-7 MHz curvilinear array transducers (SAMSUNG RS80A Ultrasound System). RESULTS: Out of 55 patients, Doppler sonography demonstrated echogenic plaques in 32 patients and corkscrew collaterals in 15 patients. Monophasic waveform with peak systolic velocity ratio of >2:1 was found in 42 patients, which is consistent with significant stenoses. CONCLUSION: Our study shows that Duplex Doppler sonography aided by color Doppler sonography can accurately locate the site and severity of stenosis/occlusion. It is safe, cost-effective, repeatable, and noninvasive.

A review on recent advances and applications of fish collagen.

During the processing of the fishery resources, the significant portion is either discarded or used to produce low-value fish meal and oil. However, the discarded portion is the rich source of valuable proteins such as collagen, vitamins, minerals, and other bioactive compounds. Collagen is a vital protein in the living body as a component of a fibrous structural protein in the extracellular matrix, connective tissue and building block of bones, tendons, skin, hair, nails, cartilage and joints. In recent years, the use of fish collagen as an increasingly valuable biomaterial has drawn considerable attention from biomedical researchers, owing to its enhanced physicochemical properties, stability and mechanical strength, biocompatibility and biodegradability. This review focuses on summarizing the growing role of fish collagen for biomedical applications. Similarly, the recent advances in various biomedical applications of fish collagen, including wound healing, tissue engineering and regeneration, drug delivery, cell culture and other therapeutic applications, are discussed in detail. These applications signify the commercial importance of fish collagen for the fishing industry, food processors and biomedical sector.

Sauromatum guttatum extract promotes wound healing and tissue regeneration in a burn mouse model via up-regulation of growth factors.

Contexts: Sauromatum guttatum (Wall.) Schott (Araceae) has been traditionally used for the treatment of wounds. Objectives: This study evaluates the healing and tissue regeneration potential of S. guttatum extract in burn wounds. Materials and methods: S. guttatum extract was analysed using various chemical tests, thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Moreover, the extract was tested against burn associated bacteria and minimum inhibitory concentration (MIC) was also calculated. Wound healing and tissue regeneration potential was assessed using a thermally induced burn BALBc mouse model. S. guttatum extract (2% w/w) prepared in petroleum jelly, vehicle and positive control [silver sulfadiazine (SD)] groups was applied three times a day. The treatment was continued for 15 d and wound closure was measured and photographed on day 5, 10 and 15. The burnt tissues excised from wounds were subjected to histological and comparative gene expression analysis. Results: The results of the chemical tests indicated the presence of alkaloids, saponins, phenols, phytosterols, tannins, and flavonoids, while TLC and HPLC analysis indicated the presence of various compounds. The extract showed excellent activity against the tested pathogens. The lowest MIC (125 µg/mL) was observed against Staphylococcus aureus. A considerable decrease in wound area (72%) was observed in extract-treated group. Histological examination of extract-treated group showed good signs of wound healing with complete re-epithelialization and better tissue regeneration. Comparative gene expression analysis revealed the up-regulation of wound healing related PDGF, EGF and FGF genes. Conclusions: S. guttatum extract may be used to isolate bioactive constituents for the treatment of burn wounds.

Development of modified montmorillonite-bacterial cellulose nanocomposites as a novel substitute for burn skin and tissue regeneration.

Bacterial cellulose (BC) is a promising biopolymer with wound healing and tissue regenerative properties but lack of antimicrobial property limits its biomedical applications. Therefore, current study was proposed to combine wound healing property of BC with antimicrobial activity of montmorillonite (MMT) and modified montmorillonites (Cu-MMT, Na-MMT and Ca-MMT) to design novel artificial substitute for burns. Designed nanocomposites were characterized through Fe-SEM, FTIR and XRD. The antimicrobial activities of composites were tested against Escherichia coli, Salmonella typhimurium, Citrobacter fruendii, Pseudomonas aeruginosa, Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus. Tissue regeneration and wound healing activities of the composites were assessed in burn mice model. Physico-chemical characterization confirmed the loading of MMT onto surface and BC matrix. Modified MMTs-BC nanocomposites showed clear inhibitory zone against the tested pathogens. Animals treated with modified MMTs-BC nanocomposites exhibited enhanced wound healing activity with tissue regeneration, reepithelialization, healthy granulation and vascularization. These findings demonstrated that modified MMTs-BC nanocomposites could be used as a novel artificial skin substitute for burn patients and scaffold for skin tissue engineering.