Modern techniques for wound coverage of the thermally injured upper extremity

The use of flaps; synthetic, dermal analogues; cultured skin substitutes; or a combination of these may one day help return severely burned arms to normal function and appearance. The complexity and expense of these alternatives limits their use in commonplace burns. As the techniques are refined with increased experience, so also will the roles for each of these options. Fortunately, an excellent result is still possible in most situations using simple autograft. The availability of these numerous choices to acutely cover the thermally injured upper extremity should not distract us from the gold standard of split-thickness skin graft (Fig. 7).     

A new approach to determine solar potential using terrestrial images

Before installing Photovoltaic (PV) panels at a place it is important to estimate the solar potential of the place. Most approaches available in literature do not consider the presence of surrounding obstructions, thus leading to wrong estimates. Light Detection and Ranging (LiDAR) data or 3D (Geographic Information System) GIS based approaches consider obstructions but prove cost-effective only at city-wide scales. This paper presents a cost-effective, accurate, and scalable approach for this purpose. The proposed approach utilizes terrestrial images of surroundings and identifies obstructions present therein. Using the azimuth and elevation angles of the principal axes of the terrestrial images the azimuth and elevation angles of each pixel in these images are determined. Using thresholding and morphological closing the terrestrial images are segmented into sky and non-sky zones. Sun is considered visible at the point of interest if it lies in the sky zone. The position of the Sun is determined using the solar position algorithm and the irradiance reaching the Earth surface is computed using the modified radiative transfer model. Finally, the total irradiance over a chosen time period at a given location is estimated by integrating the irradiances for the duration when the Sun is visible.     

Dysregulated TGF‐β signaling alters bone microstructure in a mouse model of Loeys‐Dietz syndrome

Loeys‐Dietz syndrome (LDS) is a connective tissue disorder characterized by vascular and skeletal abnormalities resembling Marfan syndrome, including a predisposition for pathologic fracture. LDS is caused by heterozygous mutations in the genes encoding transforming growth factor‐β (TGF‐β) type 1 and type 2 receptors. In this study, we characterized the skeletal phenotype of mice carrying a mutation in the TGF‐β type 2 receptor associated with severe LDS in humans. Cortical bone in LDS mice showed significantly reduced tissue area, bone area, and cortical thickness with increased eccentricity. However, no significant differences in trabecular bone volume were observed. Dynamic histomorphometry performed in calcein‐labeled mice showed decreased mineral apposition rates in cortical and trabecular bone with normal numbers of osteoblasts and osteoclasts. Mechanical testing of femurs by three‐point bending revealed reduced femoral strength and fracture resistance. In vitro, osteoblasts from LDS mice demonstrated increased mineralization with enhanced expression of osteoblast differentiation markers compared with control cells. These changes were associated with impaired TGF‐β1–induced Smad2 and Erk1/2 phosphorylation and upregulated TGF‐β1 ligand mRNA expression, compatible with G357W as a loss‐of‐function mutation in the TGF‐β type 2 receptor. Paradoxically, phosphorylated Smad2/3 in cortical osteocytes measured by immunohistochemistry was increased relative to controls, possibly suggesting the cross‐activation of TGF‐β–related receptors. The skeletal phenotype observed in the LDS mouse closely resembles the principal structural features of bone in humans with LDS and establishes this mouse as a valid in vivo model for further investigation of TGF‐β receptor signaling in bone. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1447–1454, 2015.     

Evaluation of plasmid DNA stability against ultrasonic shear stress and its in vitro delivery efficiency using ionic liquid [Bmim][PF6]

The hydrophobic ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate [Bmim][PF₆] forms nanostructures with negatively charged plasmid DNA through electrostatic interactions. The formation of plasmid DNA/IL nanostructures was confirmed by measuring the zeta potential of plasmid DNA as well as plasmid DNA/IL nanostructures. The zeta potential of the nanostructures was positive, although plasmid DNA is negatively charged. The positive zeta potential is due to the complexation between plasmid DNA and positively charged ionic liquid [Bmim][PF₆]. The ability of ionic liquid [Bmim][PF₆] to protect plasmid DNA against ultrasonic shear stress was also investigated using an agarose gel electrophoretic assay and showed that ionic liquid stabilizes plasmid DNA against ultrasonication. The plasmid DNA and plasmid DNA/IL nanostructures were subjected to ultrasonic shear stress for different time periods and the biological functionality of pristine plasmid DNA (i.e., expression of the eGFP gene) as well as the self-assembled nanostructures was investigated in vitro using three different cell lines, COS7, HEK293 and HeLa. Ionic liquid [Bmim][PF₆] protected the plasmid DNA against ultrasonic shear stress and also enhanced gene transfection efficiency in vitro. Furthermore, the cytotoxicity of ionic liquid [Bmim][PF₆] was assayed in vitro using all three cell lines and the toxicity was very low. Therefore, the ionic liquid [Bmim][PF₆] stabilizes plasmid DNA against ultrasonic shear stress and also enhances its in vitro delivery efficiency.

The hydrophobic ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate [Bmim][PF₆] forms ultrasonically stable and functional nanostructures with negatively charged plasmid DNA through electrostatic interactions.     

A novel approach to formulation factor of aceclofenac eye drops efficiency evaluation based on physicochemical characteristics of in vitro and in vivo permeation

The purpose of the present study was to evaluate aceclofenac eye drop through excised goat cornea. Raising pH of the formulation from 6.0 to 8.0, effect of different preservatives or effect of viscosity enhancer decreases apparent permeability coefficient. Topical ophthalmic NSAID are used to treat ocular surface and anterior segment inflammation as well as post operative management of pain and inflammation. Aceclofenac’s unique chemical structure makes it both a potent anti inflammatory drug and lipophilic molecule that penetrates ocular tissue, ensuring relief of pain in cataract and refractive surgery and corneal abrasion. The octanol/water partition coefficient of aceclofenac drug is 1.86 ± 0.75. Permeation characteristics of the drug were evaluated by putting 1 ml formulation on freshly excised goat cornea fixed between donor and receptor compartments of an all-glass modified Franz diffusion cell and measuring the drug permeated in the receptor by spectrophotometry at 275 nm, after 120 min. The results suggest that aceclofenac ophthalmic solution (pH 7) containing BAC provides increased in vitro ocular availability through goat corneas. The combination of methyl paraben and propyl paraben MP–PP preservative in aceclofenac ophthalmic eye drop 0.1% formulated in phosphate buffer increases transcorneal permeation. The developed formulations were evaluated for their pharmacodynamics in albino rabbits, by measuring in-vivo study and were compared to a marketed voltrane ophthalmic solution.     

Melatonin protects against experimental reflux esophagitis

Abstract:  Reflux esophagitis (RE), a major gastrointestinal disorder results from excess exposure of the esophageal mucosa to acidic gastric juice or bile-containing duodenal contents refluxed via an incompetent lower esophageal sphincter. Recent studies implicated oxygen derived free radicals in RE induced esophageal mucosal damage resulting in mucosal inflammation. Thus, control over free radical generation and modulation of inflammatory responses might offer better therapeutic effects to counteract the severity of RE. In this context we investigated the effect of melatonin against experimental RE in rats. Melatonin pretreatment significantly reduced the haemorrhagic lesions and decreased esophageal lipid peroxidation aggravated by RE. Moreover, the depleted levels of superoxide dismutase and glutathione observed in RE were replenished by melatonin signifying its free radical scavenging properties and antioxidant effects resulting in the improvement of esophageal defense mechanism. Further melatonin repressed the upregulated levels of expression of proinflammatory cytokines like, TNF-α, IL-1β and IL-6 in RE. However, increased levels of the anti-inflammatory cytokine IL-10 remained unaltered after melatonin administration signifying its immunomodulatory effect through suppression of Th1-mediated immune responses. The involvement of receptor dependent actions of melatonin against RE were also investigated with MT2 receptor antagonist, luzindole (LUZ). LUZ failed to antagonize melatonin's protective effects against RE indicating that melatonin mediated these beneficial effects in a receptor-independent fashion. Thus, esophageal mucosal protection elicited by melatonin against experimental RE is not only dependent on its free radical scavenging activity but also mediated in part through its effect on the associated inflammatory events in a receptor-independent manner.     

Arylalkyl ketones, benzophenones, desoxybenzoins and chalcones inhibit TNF-α induced expression of ICAM-1: structure-activity analysis

The interaction between leukocytes and the vascular endothelial cells (EC) via cellular adhesion molecules plays an important role in the pathogenesis of various inflammatory and autoimmune diseases. Small molecules that block these interactions have been targeted as potential therapeutic agents against acute and chronic inflammatory diseases. In an effort to identify potent intercellular cell adhesion molecule-1 (ICAM-1) inhibitors, a large number of arylalkyl ketones, benzophenones, desoxybenzoins and chalcones and their analogs (54 in total) have been synthesized and screened for their ICAM-1 inhibitory activity. The structure-activity relationship studies of these compounds identified three potent chalcone derivatives and also demonstrated the possible mechanism for their ICAM-1 inhibitory activities. The most active compound was found to be 79.     

Search of antimycobacterial activities in hybrid molecules with benzopyran skeleton

A series of hybrid molecules (7–9, 12, 13, and 14–18) consisting of chromans and pyrolidines or cyclic amines were prepared either by (3 + 2) cycloaddition of nitrostyrenes and azomethine ylide or by three component reactions of chromanyl aldehydes, acetylenes, and cyclic amines. All the synthesized compounds were evaluated against both avirulent (H37Ra) and virulent (H37Rv) strains of Mycobacterium tuberculosis. Out of all the compounds screened, compounds 16, 17, and 18 were found to be active against the virulent strain M. tubercolosis H37Rv displaying MIC in the range of 6.25–1.56 μg/ml against.     

Transnasal Fixation of NOE Fracture: Minimally Invasive Approach

Purpose  

Nasal fractures may occur in association with other facial injuries like Le-forte II and III and also severe comminuted midface fractures or by themselves. Bony fractures of the nose may involve one or both nasal bones, the frontal process of the maxilla, the bony septum, and in severe trauma the nasal–orbital–ethmoid complex. Treatment of these fractures range from closed reduction and support to open reduction and miniplate osteosynthesis. Purpose of this article is to describe a technique of managing nasal bone fractures associated with midface fractures.