Mast cell density in gastric biopsies of pediatric age group and its relation to inflammation and presence of Helicobacter pylori

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to investigate the relationship between mast cell density, histological severity of gastritis, and presence of Helicobacter pylori (H. pylori) in the antral mucosa of pediatric patients.</p> <p>Methods</p> <p>The study included 352 (192 male and 160 female, < 14 years old) patients. All cases underwent endoscopy, and biopsies were obtained for histopathological examination and evaluation of Helicobacter pylori. All biopsies were evaluated according to the Sydney system and mast cell density in the antral mucosa was analyzed by Giemsa stain. Spearman's correlation test was used to determine the relationship between mast cell density and other histopathological parameters. The comparison of mast cell density between H. pylori positive and negative groups was analyzed by Mann Whitney U test.</p> <p>Results</p> <p>Mast cell density was 12.6 ± 0.87 in 0.25 mm²(0–81). Means of severity of gastric inflammation in H. pylori-positive and negative patients were 1.7 ± 0.6 and 0.6 ± 0.7, respectively, which was statistically significant (p = 0.0001). Mast cell density was not correlated with presence and degree of inflammation, activity, presence and score of H. pylori in the antrum (p > 0.05). There was no significant correlation between mast cell density and allergy.</p> <p>Discussion</p> <p>We concluded that there may be some other ways for contribution of mast cells in pathologic processes involving gastrointestinal tract in children.</p

Advances in antimicrobial photodynamic inactivation at the nanoscale

The alarming worldwide increase in antibiotic resistance amongst microbial pathogens necessitates a search for new antimicrobial techniques, which will not be affected by, or indeed cause resistance themselves. Light-mediated photoinactivation is one such technique that takes advantage of the whole spectrum of light to destroy a broad spectrum of pathogens. Many of these photoinactivation techniques rely on the participation of a diverse range of nanoparticles and nanostructures that have dimensions very similar to the wavelength of light. Photodynamic inactivation relies on the photochemical production of singlet oxygen from photosensitizing dyes (type II pathway) that can benefit remarkably from formulation in nanoparticle-based drug delivery vehicles. Fullerenes are a closed-cage carbon allotrope nanoparticle with a high absorption coefficient and triplet yield. Their photochemistry is highly dependent on microenvironment, and can be type II in organic solvents and type I (hydroxyl radicals) in a biological milieu. Titanium dioxide nanoparticles act as a large band-gap semiconductor that can carry out photo-induced electron transfer under ultraviolet A light and can also produce reactive oxygen species that kill microbial cells. We discuss some recent studies in which quite remarkable potentiation of microbial killing (up to six logs) can be obtained by the addition of simple inorganic salts such as the non-toxic sodium/potassium iodide, bromide, nitrite, and even the toxic sodium azide. Interesting mechanistic insights were obtained to explain this increased killing

Breastfeeding and Helicobacter Pylori Infection in Children with Digestive Symptoms

Objective: This study aims to evaluate the role of breastfeeding in the acquisition of Helicobacter Pylori (H. pylori) infection in Iran and to compare the histopathologic changes occurring in children feeding on breast milk with those in infants feeding on formula. Methods: In a case-control study parents of children with and without H. pylori infection who had undergone endoscopic survey and gastric biopsy in the Children's Medical Center, Tehran, were asked about their feeding practices during the first 6 months after birth, the duration of breastfeeding period, the symptoms, and the duration of symptoms and concomitant diseases. Findings: A total of 154 children were included in this study. From this sample, 77 children formed the case group and 77 children formed the control group. A significant difference was found between H. pylori infection and feeding with formula (P=0.045). In case group, a significant difference was found between breastfeeding and age of the infected child (P=0.034), shorter duration of symptoms (P=0.016), and finally degree of H. pylori colonization (P=0.021). Conclusion: It appears that breastfeeding in the first 6 months after birth can decrease the degree of H. pylori colonization, postpone infection until older age, shorten the duration of symptoms, and be concomitant with milder gastritis

Application of fnbA gene as new target for the species-specific and quantitative detection of Staphylococcus aureus directly from lower respiratory tract specimens by real time PCR

Staphylococcus aureus is a significant cause of hospital-acquired pneumonia (HAP), particularly in mechanically ventilated patients. We used the fibronectin-binding protein A gene (fnbA) for the species-specific and quantitative detection of S. aureus directly from lower respiratory tract (LRT) specimens by a Taq Man real time PCR. For this reason, a total of 269 lower respiratory tract (LRT) specimens collected from patients with hospital-acquired pneumonia were assayed. Amplification of fnbA in serial dilutions ranged from 10 9 CFU/ ml to 10 2 CFU/ml. Standard curve of triplicate every dilution had slope 3.34 ± 0.1 and R 2 > 0.99 with SD 0.1. Based on these data, the sensitivity and specificity of the newly developed real time PCR targeting the fnbA gene were both 100%. The Cohen′s Kappa test showed the Kappa value of 1.0. The fnbA gene is a potential marker for the species-specific detection of S. aureus and can be used to detect this bacterium in any clinical specimens by real time PCR. Moreover, this method reduces the time needed for quantitative detection of Staphylococcus aureus from LRT specimens to nearly 2 hours compared to 1 to 4 days for culture and provided sensitivity equal to or greater than culture