The Use of an Autologous Cell Harvesting and Processing Device to Decrease Surgical Procedures and Expedite Healing in Two Pediatric Burn Patients.

INTRODUCTION: Autologous cell harvesting and processing devices are designed to facilitate the harvesting of cells using enzymatic and physical disruption techniques to immediately apply non-cultured autologous cell suspension (ACS) to the wound area. OBJECTIVE: This case report evaluates clinical outcomes following application of cellular suspension with split-thickness skin grafts (STSGs) as an adjunct for definitive closure of burn injuries and donor sites in 2 pediatric patients. MATERIALS AND METHODS: The cases were performed under a humanitarian use protocol following institutional review board approval at St. Christopher's Hospital for Children (Philadelphia, PA). RESULTS: The first patient was a 4-year-old girl with partial- and full-thickness (32% total body surface area) burn injuries of her head, trunk, flank, arms, thighs, and feet. The patient was discharged 19 days following ACS treatment. The second patient was an 18-month-old girl with partial- and full-thickness (21% total body surface area) burns involving the bilateral lower extremities. She was discharged 22 days after ACS treatment with widely meshed autograft. Neither patient required additional surgical interventions. All treatment and donor areas for both patients remained uninfected and neither patient experienced any unexpected treatment-related adverse events. CONCLUSIONS: These cases are the first of their kind reported in the pediatric population and suggest ACS in conjunction with STSGs can help decrease surgical procedures and expedite healing in pediatric patients with large surface burns.

Drug-induced Liver Fibrosis: Testing Nevirapine in a Viral-like Liver Setting Using Histopathology, MALDI IMS, and Gene Expression.

Nevirapine (NVP) is associated with hepatotoxicity in 1-5% of patients. In rodent studies, NVP has been shown to cause hepatic enzyme induction, centrilobular hypertrophy, and skin rash in various rat strains but not liver toxicity. In an effort to understand whether NVP is metabolized differently in a transiently inflamed liver and whether a heightened immune response alters NVP-induced hepatic responses, female brown Norway rats were dosed with either vehicle or NVP alone (75 mg/kg/day for 15 days) or galactosamine alone (single intraperitoneal [ip] injection on day 7 to mimic viral hepatitis) or a combination of NVP (75/100/150 mg/kg/day for 15 days) and galactosamine (single 750 mg/kg ip on day 7). Livers were collected at necropsy for histopathology, matrix-assisted laser desorption/ionization imaging mass spectrometry and gene expression. Eight days after galactosamine, hepatic fibrosis was noted in rats dosed with the combination of NVP and galactosamine. No fibrosis occurred with NVP alone or galactosamine alone. Gene expression data suggested a viral-like response initiated by galactosamine via RNA sensors leading to apoptosis, toll-like receptor, and dendritic cell responses. These were exacerbated by NVP-induced growth factor, retinol, apoptosis, and periostin effects. This finding supports clinical reports warning against exacerbation of fibrosis by NVP in patients with hepatitis C.

Cardiolipin profiles as a potential biomarker of mitochondrial health in diet-induced obese mice subjected to exercise, diet-restriction and ephedrine treatment.

Cardiolipin (CL) is crucial for mitochondrial energy metabolism and structural integrity. Alterations in CL quantity or CL species have been associated with mitochondrial dysfunction in several pathological conditions and diseases, including mitochondrial dysfunction-related compound attrition and post-market withdrawal of promising drugs. Here we report alterations in the CL profiles in conjunction with morphology of soleus muscle (SM) and brown adipose tissue (BAT) in diet-induced obese (DIO) mice, subjected to ephedrine treatment (EPH: 200 mg kg(-1) day(-1) orally), treadmill exercise (EX: 10 meters per min, 1 h per day), or dietary restriction (DR: 25% less of mean food consumed by the EX group) for 7 days. Mice from the DR and EPH groups had a significant decrease in percent body weight and reduced fat mass compared with DIO controls. Morphologic alterations in the BAT included brown adipocytes with reduced cytoplasmic lipid droplets and increased cytoplasmic eosinophilia in the EX, DR and EPH groups. Increased cytoplasmic eosinophilia in the BAT was ultrastructurally manifested by increased mitochondrial cristae, fenestration of mitochondrial cristae, increased electron density of mitochondrial matrix, and increased complexity of shape and elongation of mitochondria. Mitochondrial ultrastructural alterations in the SM of the EX and DR groups included increased mitochondrial cristae, cup-shaped mitochondria and mitochondrial degeneration. All four CL species (tri-linoleoyl-mono-docosahexaenoyl, tetralinoleoyl, tri-linoleoyl-mono-oleoyl, and di-linoleoyl-di-oleoyl) were increased in the BAT of the DR and EPH groups and in the SM of the EPH and EX groups. In conclusion, cardiolipin profiling supported standard methods for assessing mitochondrial biogenesis and health, and may serve as a potential marker of mitochondrial dysfunction in preclinical toxicity studies.

Brief communication: intraperitoneal galactosamine misdosing as a possible interpretation for responder/nonresponder phenotypes.

Previous reports investigating the mechanisms of galactosamine toxicity have discussed the presence of responders and nonresponders after intraperitoneal (IP) administration of a toxic dose. The incidence of nonresponders has been reported to be as high as 47%. To rule out inadvertent intestinal, solid organ, or subcutaneous injection as at least a partial cause for the variability, we performed midline incisions and dosed 10 rats via a flexible catheter, with a toxic dose of galactosamine. Results were compared to a previous range finding study with IP-injected rats. As opposed to the IP-injected rats that had a roughly 50% response rate (based on serum alanine aminotransferase [ALT] elevation) and 100% of the midline incision catheter-instilled rats had elevations in ALT. Saline controls had no elevations. Histopathologic examination of livers from 5 midline-incisioned rats euthanized 48 hr after dosing with the lowest ALT responses revealed portal eosinophilic infiltrates and biliary hypertrophy/hyperplasia contiguous with areas of necrosis. Examination of 5 rats with the highest ALT elevations euthanized 10 days post dose revealed similar lesions to be resolving. We conclude that a significant contribution to variability in response to IP-injected galactosamine and possibly other investigative drugs is inadvertent misinjection of all or part of the dose.

5-hydroxytryptamine (5HT)-induced valvulopathy: compositional valvular alterations are associated with 5HT2B receptor and 5HT transporter transcript changes in Sprague-Dawley rats.

Several drugs have been linked to valvulopathy in humans, including therapeutic agents for obesity, Parkinson's disease and migraine. There is increasing evidence that the 5-hydroxytryptamine 2B receptor (5HT2BR) activation and/or increased circulating 5HT (5-hydroxytryptamine) may play a significant role in the pathogenesis of drug-induced valvulopathy. In the present study, we investigated whether 7-day 5HT subcutaneous injections led to structural and compositional abnormalities in conjunction with transcriptomic modulation of 5HT2BR and 5HT transporter (5HTT) genes in the aortic and mitral valves of Sprague-Dawley (SD) rats. Subcutaneous injections of 5HT for 7 days resulted in thickening and compositional alteration of aortic and mitral valves in SD rats. More specifically, valve-leaflets from 5HT-treated rats had greater valve thickness, a higher amount of glycosaminoglycans (GAGs) and a lower amount of collagen. The compositional alteration was associated with up-regulation and down-regulation of 5HT2BR and 5HTT genes, respectively. The present study strongly suggests that the activation of 5HT2BR and inhibition of 5HTT played a significant role in the pathogenesis of 5HT-induced valvulopathy in SD rats. Thus, these findings further highlight the necessity and/or utilization of animal models to screen potential valvular effects of serotonergic compounds.

5-Hydroxytryptamine (5HT) receptors in the heart valves of cynomolgus monkeys and Sprague-Dawley rats.

5-Hydroxytryptamine-2B receptor (5HT2BR) stimulation is known to cause fibroblast mitogenesis, and the mitogenic effect has been proposed to trigger valvular heart disease in humans. In this study, we used real-time polymerase chain reaction (TaqMan) to quantify transcript levels of 5HT2B, 5HT2C, and 5HT1B receptors and immunohistochemistry (IHC) to detect the tissue localization of these receptors in the normal heart valves of cynomolgus (CM) monkeys and Sprague-Dawley (S-D) rats. In both species, positive immunostaining was noted for 5HT1B and 5HT2B receptors in mitral, tricuspid, aortic, and pulmonary valves, and the cell types showing positive staining were interstitial cells and endothelial cells lining the valve leaflet. In CM monkeys, 5HT2CR was expressed only in the endothelial cells lining the leaflet, whereas S-D valves were negative for this receptor. IHC results were correlated with 5HT2B and 5HT1B receptor transcripts for all four valves. However, 5HT2C receptor transcripts were lower than 5HT2B or 5HT1B in all CM monkey valves, whereas 5HT2C transcripts were below the level of detection in any of the S-D rat valves. Our data showed the expression of 5HT2B, 5HT1B, and 5HT2C receptors in the normal heart valves of CM monkeys and S-D rats, and IHC and TaqMan techniques may be used to study the potential mechanism of compounds with 5HT2BR agonist activity.