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Oliveira GV, Hawkins HK, Chinkes D, Burke A, Pasqua Tavares AL, Ramos-e-Silva M, Albrecht TB, Kitten GT, Herndon DN. Hypertrophic versus non hypertrophic scars compared by immunohistochemistry and laser confocal microscopy: type I and III collagens. Although dermal collagens appear increased in hypertrophic scars, this has not been tested in tissue samples using objective methods. We compared the expression of types I and III collagen in hypertrophic and non hypertrophic scars at 6–12 and 18–24 months after burn using a quantitative method. Among 17 patients with extensive burns, 3 patients had acute scars, 8 had hypertrophic or non hypertrophic scars at 6–12 months after burn and 6 had hypertrophic or non hypertrophic scars at 18–24 months after burn. After clinical assessment of scars using the Vancouver scale, immunohistochemistry for types I and III collagens was performed. Images were captured with a laser scanning confocal microscope and the relative amounts of types I and III collagens were determined in superficial and deep dermis. The effects of time and scar type were assessed using two-way analysis of variance (ANOVA) and Tukey's test. Collagen III scar/normal ratios were higher in hypertrophic scars at both time points ( P = 0.05). There were no differences in collagen I scar/normal ratios. Large variation was observed in scars during the acute phase regarding the expression of collagens. Easily accessed by immunohistochemistry and confocal microscopy, type III collagen deposition may help in determining scar phenotype, differentiating hypertrophic and non hypertrophic scars. [ABSTRACT FROM AUTHOR]

Background and Purpose: The present study investigated whether the pathophysiological changes induced by burn and smoke inhalation are modulated by parenteral administration of Na(2)S, a H(2)S donor.Experimental Approach: The study used a total of 16 chronically instrumented, adult female sheep. Na(2)S was administered 1 h post injury, as a bolus injection at a dose of 0.5 mg.kg(-1) and subsequently, as a continuous infusion at a rate of 0.2 mg.kg(-1).h(-1) for 24 h. Cardiopulmonary variables (mean arterial and pulmonary arterial blood pressure, cardiac output, ventricular stroke work index, vascular resistance) and arterial and mixed venous blood gases were measured. Lung wet-to-dry ratio and myeloperoxidase content and protein oxidation and nitration were also measured. In addition, lung inducible nitric oxide synthase expression and cytochrome c were measured in lung homogenates via Western blotting and enzyme-linked immunosorbent assay (elisa) respectively.Key Results: The H(2)S donor decreased mortality during the 96 h experimental period, improved pulmonary gas exchange and lowered further increase in inspiratory pressure and fluid accumulation associated with burn- and smoke-induced acute lung injury. Further, the H(2)S donor treatment reduced the presence of protein oxidation and 3-nitrotyrosine formation following burn and smoke inhalation injury.Conclusions and Implications: Parenteral administration of the H(2)S donor ameliorated the pulmonary pathophysiological changes associated with burn- and smoke-induced acute lung injury. Based on the effect of H(2)S observed in this clinically relevant model of disease, we propose that treatment with H(2)S or its donors may represent a potential therapeutic strategy in managing patients with acute lung injury. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori infection leads to gastritis, peptic ulcer, and gastric cancer, in part due to epithelial damage following bacteria binding to the epithelium. Infection with cag pathogenicity island (PAI) bearing strains of H. pylori is associated with increased gastric inflammation and a higher incidence of gastroduodenal diseases. It is now known that various effector molecules are injected into host epithelial cells via a type IV secretion apparatus, resulting in cytoskeletal changes and chemokine secretion. Whether binding of bacteria and subsequent apoptosis of gastric epithelial cells are altered by cag PAI status was examined in this study. Methods: AGS, Kato III, and N87 human gastric epithelial cell lines were incubated with cag PAI-positive or cag PAI-negative strains of H. pylori in the presence or absence of clarithromycin. Binding was evaluated by flow cytometry and scanning electron microscopy. Apoptosis was assessed by detection of DNA degradation and ELISA detection of exposed histone residues. Results: cag PAI-negative strains bound to gastric epithelial cells to the same extent as cag PAI-positive strains. Both cag PAI-positive and cag PAI-negative strains induced apoptosis. However, cag PAI-positive strains induced higher levels of DNA degradation. Incubation with clarithromycin inactivated H. pylori but did not affect binding. However, pretreatment with clarithromycin decreased infection-induced apoptosis. Conclusions: cag PAI status did not affect binding of bacteria to gastric epithelial cells but cag PAI-positive H. pylori induced apoptosis more rapidly than cag PAI-negative mutant strains, suggesting that H. pylori binding and subsequent apoptosis are differentially regulated with regard to bacterial properties. [ABSTRACT FROM AUTHOR]

The hypercatabolism after massive pediatric burns has been effectively treated with recombinant human growth hormone, an anabolic agent that stimulates protein synthesis and abrogates growth arrest. While experimental studies have shown increased potential for fibrosis induced by growth hormone therapy, adverse effects on human scars have not been investigated. Our aim was to evaluate hypertrophic scar formation in 62 patients randomized to receive injections of 0.05 mg/kg/day of recombinant human growth hormone or placebo, from discharge until 1 year after burn. Scar scales were used to evaluate scar-severity at discharge, 6, 9, 12, and 18–24 months after burn, by three observers blinded to treatment. Computer-assisted planimetry allowed quantification of percentage of hypertrophic scar formation. Types I and III collagens were localized and quantified in scars and normal skin of patients from both groups, using immunohistochemistry with confocal laser microscopy analysis. Insulin-like growth factor-1 blood levels helped assess compliance. Statistical analysis showed that scar hypertrophy significantly increased from 6 to 12 months after injury in both groups, while decreasing at 18–24 months postburn. Types I and III collagens were statistically increased in the reticular layer of scars from both groups when compared to paired normal skin. Insulin-like growth factor-1 was significantly increased in the recombinant human growth factor-treated group. No differences were seen when recombinant human growth factor and control groups were compared using the scar scales, planimetry, or immunohistochemistry. We concluded that recombinant human growth hormone therapy did not adversely affect scar formation and should not contraindicate the administration of recombinant human growth hormone as a therapeutic approach to severely burned children. [ABSTRACT FROM AUTHOR]

Objective To develop a cost-effective protocol for diagnosing primary ciliary dyskinesia (PCD). Study Design Retrospective chart review in a tertiary care academic medical center. Methods A review of the electron microscopy logbook identified all patients who had a suspected diagnosis of PCD. Biopsy of respiratory tract mucosa was performed using a cytology brush or a cup forceps in the outpatient clinic or operating room (OR). Outcome measures were to determine the diagnostic adequacy of cytological evaluation compared with tissue biopsy and to determine whether an adequate nasal mucosa sample can be collected in the outpatient clinic setting as compared with the OR and the use of general anesthesia. Results Twenty-seven patients underwent 31 biopsies. Fifteen specimens were collected with a cup forceps, and 16 with a cytology brush. The sampling sites were nasal mucosa in 28 cases and trachea in the rest. Twelve specimens (39%) were collected in the clinic; the rest were obtained in the OR in conjunction with another procedure. Neither method of specimen collection nor mode of anesthesia made a significant difference in the probability of obtaining an adequate specimen. Ten samples were nondiagnostic: cytological evaluation, 31% (n = 16); tissue biopsy, 27% (n = 15); clinic, 42% (n = 12); and OR, 31% (n = 16). The cost of evaluating ciliary motion at our institution was $150, with an additional charge of $1297 for electron microscopic evaluation. The nonprofessional fee for an outpatient nasal biopsy was $98; in the OR the cost of anesthesia supplies, surgical suite, recovery room, and day-surgery bed was at least $1860. Conclusion Our results suggest that the optimal method for diagnosis of PCD is in the outpatient clinic with specimen collection by means of either a cup forceps or a cytology brush. [ABSTRACT FROM AUTHOR]

Background: Excessive production of nitric oxide (NO) by neuronal NO synthase (nNOS, NOS-1) is critically involved in acute lung injury and systemic inflammation after burn and smoke inhalation. We hypothesized that 7-nitroindazole (7-NI), a selective nNOS inhibitor, blocks molecular mechanisms contributing to ovine lung injury. Methods: Ewes (n=11) were surgically prepared for study and randomly allocated to an injured (40% total body surface area flame burn and 48 breaths of cotton smoke) untreated control group (n=6) or an injury group treated with 7-NI (1mg/kg/h, n=5), infused over the 24-h study period, starting 1 h post injury. Results: The double hit injury was associated with systemic inflammation and oxidative stress, as evidenced by a 2.5-fold increase in plasma nitrite/nitrate (NOx) levels, as well as 6-fold, 2-fold and 3-fold increases in interleukin-8 (IL-8), myeloperoxidase (MPO) and malondialdehyde (MDA) lung tissue concentrations, respectively. These molecular changes were linked to severe pulmonary dysfunction. Compared to untreated controls, 7-NI significantly reduced NOx plasma levels (8.4±1 vs. 26±10 µmol/L) and decreased IL-8, MPO (3.9±0.2 vs. 5.8±0.7 U/g tissue) and MDA lung tissue content (2.7±0.3 vs. 6.6±1.1 nmol/mg protein), thereby improving PaO2/FiO2 ratio (456±40 vs. 313±56, each p<0.05). Conclusion: These data show that nNOS-derived NO plays a pivotal role in combined burn and smoke injury and suggest selective nNOS inhibition as a useful approach to attenuate pulmonary injury. [ABSTRACT FROM AUTHOR]