Explore the vast range of titles available.

The inadequate therapeutic opportunities associated with carbapenem-resistant Pseudomonas aeruginosa (CRPA) clinical isolates impose a search for innovative strategies. Therefore, our study aimed to characterize and evaluate two locally isolated phages formulated in a hydrogel, both in vitro and in vivo, against CRPA clinical isolates. The two phages were characterized by genomic, microscopic, phenotypic characterization, genomic analysis, in vitro and in vivo analysis in a Pseudomonas aeruginosa-infected skin thermal injury rat model. The two siphoviruses belong to class Caudovirectes and were named vB_Pae_SMP1 and vB_Pae_SMP5. Each phage had an icosahedral head of 60 ± 5 nm and a flexible, non-contractile tail of 170 ± 5 nm long, while vB_Pae_SMP5 had an additional base plate containing a 35 nm fiber observed at the end of the tail. The hydrogel was prepared by mixing 5% w/v carboxymethylcellulose (CMC) into the CRPA propagated phage lysate containing phage titer 108 PFU/mL, pH of 7.7, and a spreadability coefficient of 25. The groups were treated with either Phage vB_Pae_SMP1, vB_Pae_SMP5, or a two-phage cocktail hydrogel cellular subepidermal granulation tissues with abundant records of fibroblastic activity and mixed inflammatory cell infiltrates and showed 17.2%, 25.8%, and 22.2% records of dermal mature collagen fibers, respectively. In conclusion, phage vB_Pae_SMP1 or vB_Pae_SMP5, or the two-phage cocktails formulated as hydrogels, were able to manage the infection of CRPA in burn wounds, and promoted healing at the injury site, as evidenced by the histopathological examination, as well as a decrease in animal mortality rate. Therefore, these phage formulae can be considered promising for clinical investigation in humans for the management of CRPA-associated skin infections.

The results of evaluating the therapeutic effectiveness of a composition based on antiradiation serum and metabolic products of bifidobacteria on laboratory animals subjected to experimental combined radiation and thermal effects are presented. In this work 124 mongrel white rats of both sexes with a live weight of 180–220 g were used as a biological model. The simulation of radiation damage to the body was carried out by a single external irradiation of animals on a Puma gamma installation with a 137 Cs radiation source with an exposure dose of 8.5 × 10 –2 A/kg in an absorbed dose of 7.5 Gy. Thermal injury was inflicted by applying a brass plate heated to 200°C with an area of 4.9 cm 2 with a retention exposure of eight seconds to the trimmed area of the upper third of the thigh, inducing a grade III burn. The effectiveness of the therapeutic drug was evaluated according to the following criteria: changes in the titer of the compliment, the concentration of radiotoxin and thermotoxin, changes in the methodological parameters of the peripheral blood, the degree of burn damage, survival, and life expectancy of fallen animals. The results of tests evaluating the therapeutic effectiveness of the tested composition showed that a single subcutaneous injection of a medicinal product at a dose of 20 mg/kg followed by application of an anti-burn ointment based on bee podmore and St. John’s wort oil at intervals of 24, 48, and 168 h accelerated the formation of a burn scab by 1.75 times ( p < 0.01), complete rejection of the burn scab increased by 1.15 times ( p < 0.05), and the complete healing of the burn wound accelerated by 1.18 times compared with the control groups, thereby increasing the survival rate to 87.5% ( p < 0.05) of animals exposed to two-factor exposure to the affected factors, while increasing the average life expectancy to 28.0 days versus 6.5 days in the control (irradiation + burn).

PurposeTransmural thermal injury (TTI), such as esophageal erosion/ulcer and periesophageal nerve injury leading to gastric hypomotility, is not rare complications associated with pulmonary vein isolation (PVI). However, the mechanism and predicting factors of TTI have not yet been fully elucidated with second-generation cryoballoon (CB) PVI.MethodsOne hundred ten consecutive patients, who underwent CB PVI for atrial fibrillation and received esophagogastroduodenoscopy 2 days later, were investigated. The relationships between TTI and both clinical and anatomical parameters were examined. We measured the following parameters based on the computed tomography data: the angle of the left atrial (LA) posterior wall to the descending aorta (Ao) (LA-Ao angle); the branching angle of the left inferior pulmonary vein (LIPV) to the coronal plane (LIPV angle); and the minimum distance between the LA posterior wall and descending Ao enclosing the esophagus (LA-Ao distance).ResultsTTIs occurred in 19 patients (esophageal erosion in 2 and gastric hypomotility in 17). The patients with TTI were significantly older than those without TTI. In the anatomical parameters, the LIPV angle was larger and the LA-Ao distance was shorter in the TTI (+) group compared to the TTI (−) group. With the multivariate logistic regression analysis, the age (odds ratio [OR] 2.148, P = 0.022) and LA-Ao distance (OR 0.430, P = 0.013) were independent predictors of TTI.ConclusionsThe occurrence of TTI in CB PVI was associated with aging, suggesting compromised periesophageal circulation, and the anatomical proximities between the LA and the descending Ao, which enclose the esophagus.

Temperature tolerance is critical for defining the fundamental niche of ectotherms and researchers classically use either static (exposure to a constant temperature) or dynamic (ramping temperature) assays to assess tolerance. The use of different methods complicates comparison between studies and here we present a mathematical model (and R -scripts) to reconcile thermal tolerance measures obtained from static and dynamic assays. Our model uses input data from several static or dynamic experiments and is based on the well-supported assumption that thermal injury accumulation rate increases exponentially with temperature (known as a thermal death time curve). The model also assumes thermal stress at different temperatures to be additive and using experiments with Drosophila melanogaster , we validate these central assumptions by demonstrating that heat injury attained at different heat stress intensities and durations is additive. In a separate experiment we demonstrate that our model can accurately describe injury accumulation during fluctuating temperature stress and further we validate the model by successfully converting literature data of ectotherm heat tolerance (both static and dynamic assays) to a single, comparable metric (the temperature tolerated for 1 h). The model presented here has many promising applications for the analysis of ectotherm thermal tolerance and we also discuss potential pitfalls that should be considered and avoided using this model.

Burn injury is a severe form of trauma affecting more than 2 million people in North America each year. Burn trauma is not a single pathophysiological event but a devastating injury that causes structural and functional deficits in numerous organ systems. Due to its complexity and the involvement of multiple organs, in vitro experiments cannot capture this complexity nor address the pathophysiology. In the past two decades, a number of burn animal models have been developed to replicate the various aspects of burn injury, to elucidate the pathophysiology, and to explore potential treatment interventions. Understanding the advantages and limitations of these animal models is essential for the design and development of treatments that are clinically relevant to humans. This review aims to highlight the common animal models of burn injury in order to provide investigators with a better understanding of the benefits and limitations of these models for translational applications. While many animal models of burn exist, we limit our discussion to the skin healing of mouse, rat, and pig. Additionally, we briefly explain hypermetabolic characteristics of burn injury and the animal model utilized to study this phenomena. Finally, we discuss the economic costs associated with each of these models in order to guide decisions of choosing the appropriate animal model for burn research.

The purpose of our study is to use a noninvasive tomographic imaging technique with high spatial resolution to characterize and monitor biological tissue responses associated with laser thermal injury. Optical doppler tomography (ODT) combines laser doppler flowmetry (LDF) with optical coherence tomography (OCT) to obtain high resolution tomographic velocity and structural images of static and moving constituents in highly scattering biological tissues. A SurgiLase XJ150 carbon dioxide (CO ) laser using a continuous mode of 3 watts (W) was used to create first, second or third degree burns on anesthetized Sprague-Dawley rats. Additional parameters for laser thermal injury were assessed as well. The rationale for using ODT in the evaluation of laser thermal injury offers a means of constructing a high resolution tomographic image of the structure and perfusion of laser damaged skin. In the velocity images, the blood flow is coded at 1300 μm/s and 0 velocity, 1000 μm/s and 0 velocity, 700 μm/s and 0 velocity adjacent to the first, second, and third degree injuries, respectively. ODT produces exceptional spatial resolution while having a non-invasive way of measurement, therefore, ODT is an accurate measuring method for high-resolution fluid flow velocity and structural images for biological tissue with laser thermal injury.

IntroductionPreservation of muscle layer integrity during Endoscopic Submucosal Dissection (ESD) for complex colorectal lesions mandates a high-technical skillset by the operator, particularly when endoscopic access is restricted in angulated colonic segments.MethodsThe SpeedboatTM Inject/SI 10fr Device, (Creo Medical Group, UK) incorporates innovative electrocautery properties, bipolar radiofrequency (yellow pedal, 400KHz/35W) used for tissue dissection and a microwave energy (blue pedal, 5.8GHz/10W) system for coagulation. With the Speedboat-assisted Submucosal Dissection or SSD approach a ‘clean’ cut of the mucosa and submucosal layers is achieved after full contact to avert any charring. A CO2 insufflation exchange apparatus (AirsealTM, ConMed/USA) passed via one of the Gelpoint ports facilitates SDD and we describe a new procedure; air seal - Trans-Anal Speedboat Endoscopic Resection (a-TASER). With continuous CO2 insufflation the endoscopy access is improved and a constant bowel distention is sustained without causing barotrauma.ResultsAn 86mm x 81mm cm (Lateral-Spreading-Tumour-Granular-Mixed, NICE type 2) lesion at the sigmoid-descending junction was excised using the a-TASER technique under general anaesthesia. Initially, the Air Seal device was set at 7–8mmHg to allow minimal submucosal thinning and facilitate submucosal entry. At the end of the procedure the pressure was tuned to 11–12mmHg to optimise the submucosal tension. A fundamental potential of the SSD approach is the ability of submucosal tunnelling and the lateral sweeping of the submucosa in a ‘in(tunnel)-to-out(edges)’ direction. A near bloodless dissection with no sudden arterial bleeding or recourse to haemostatic forceps or instrument exchange was achieved. Inspection of the post-resection base revealed an intact muscle layer, with no signs of thermal injury. The patient had an uneventful, full and painless and discharged the next day. Histology of the pinned-out specimen showed an R0 resection of a high grade dysplastic tubulo-villous adenoma. No immediate or delayed complications were observed. At one-year follow-up, the healed scar was free of recurrence, and was covered by ‘smooth’ normalised epithelium without stenosis.ConclusionThis new trans-anal platform combining the novel SI device/SSD approach with a CO2 pressure-controlled insufflation system (a-TASER) is technically feasible and appears to facilitate the endoscopic resection of complex left-sided colorectal lesions.

Purpose This study compared the efficacy of heat insulation between 5% dextrose and 0.9% saline in radiofrequency ablation (RFA). Accordingly, temperature variations and maximum temperatures were assessed at identical distances and heat field distributions. Methods Cubes of porcine liver tissue, measuring 10 mm across, were selected to precisely align the ablation boundary with the tissue boundary. An 18-gauge electrode with a 7-mm tip was inserted into each cube (10 per group) in a stainless-steel cup containing 40 mL of 5% dextrose or 0.9% saline. Fixed ablation was performed for 3 minutes using continuous mode at 30 W, simulating the typical thermal environment during thyroid RFA. Real-time temperature measurements were recorded by sensors positioned 0, 1, 3, and 5 mm from the cube’s edge. A comparative analysis was conducted to assess the maximum temperature, temperature variation, and duration of temperatures exceeding 42℃. Results In both groups, the temperature curve declined with increasing distance from the edge of the ablated tissue. However, 0.9% saline exhibited higher maximum temperatures at 1, 3, and 5 mm compared to 5% dextrose (1 mm: 44.55°C±5.25°C vs. 34.68°C±3.07°C; 3 mm: 39.64°C±2.53°C vs. 29.22°C±2.21°C; 5 mm: 38.86°C±2.14°C vs. 28.74°C±2.51°C; all P<0.001). Considering a nerve injury threshold of 42°C, the 0.9% saline also displayed a greater proportion of samples reaching this temperature and a longer duration of temperatures exceeding it (P<0.05). Conclusion The heat insulation efficacy of 5% dextrose at 1-5 mm exceeds that of 0.9% saline at identical distances and in a common thermal environment during thyroid RFA.

Soft, wireless physiological sensors that gently adhere to the skin are capable of continuous clinical-grade health monitoring in hospital and/or home settings, of particular value to critically ill infants and other vulnerable patients, but they present risks for injury upon thermal failure. This paper introduces an active materials approach that automatically minimizes such risks, to complement traditional schemes that rely on integrated sensors and electronic control circuits. The strategy exploits thin, flexible bladders that contain small volumes of liquid with boiling points a few degrees above body temperature. When the heat exceeds the safe range, vaporization rapidly forms highly effective, thermally insulating structures and delaminates the device from the skin, thereby eliminating any danger to the skin. Experimental and computational thermomechanical studies and demonstrations in a skin-interfaced mechano-acoustic sensor illustrate the effectiveness of this simple thermal safety system and suggest its applicability to nearly any class of skin-integrated device technology. Minimizing patient risk to thermal failure in wearable electronics typically requires complex circuit control, sensors, or passive materials. Here, Yoo et al. present an active materials system with a self-inflating bladder that delaminates upon excessive heat, mitigating the risk of thermal injury.

Although accumulated evidence supports the notion that mesenchymal stem cells (MSCs) act in a paracrine manner, the mechanisms are still not fully understood. Recently, MSC-derived exosomes (MSC-Exos), a type of microvesicle released from MSCs, were thought to carry functional proteins and RNAs to recipient cells and play therapeutic roles. In the present study, we intravitreally injected MSCs derived from either mouse adipose tissue or human umbilical cord and their exosomes to observe and compare their functions in a mouse model of laser-induced retinal injury. We found that both MSCs and their exosomes reduced damage, inhibited apoptosis and suppressed inflammatory responses to obtain better visual function to nearly the same extent in vivo . Obvious down-regulation of monocyte chemotactic protein (MCP)-1 in the retina was found after MSC-Exos injection. In vitro , MSC-Exos also down-regulated MCP-1 mRNA expression in primarily cultured retinal cells after thermal injury. It was further demonstrated that intravitreal injection of an MCP-1-neutralizing antibody promoted the recovery of retinal laser injury, whereas the therapeutic effect of exosomes was abolished when MSC-Exos and MCP-1 were administrated simultaneously. Collectively, these results suggest that MSC-Exos ameliorate laser-induced retinal injury partially through down-regulation of MCP-1.