Allergic rhinitis is the most common allergic disease with negative impacts on patients' quality of life. The prevalence and pattern of sensitisation vary between different countries and populations. Identification of the most prevalent aeroallergens in each area has a very important role in diagnosis and treatment of allergic rhinitis. Iran is a fairly large country with different geo-climatic conditions and there are no data about the most prevalent aeroallergen in Mashhad City, which is the second largest city in Iran, with a semiarid climate. The aim of this study was to evaluate the prevalence of positive skin test to various common aeroallergens among allergic rhinitis patients in the city of Mashhad. Skin prick tests were performed with 27 common regional aeroallergens including grass, weed, tree, mite and mould in 311 patients with allergic rhinitis. The overall rate of sensitisation to any allergen was 81 %. 76 % of patients were poly-sensitised and weed and grass were the most prevalent allergens (77 % and 62 % respectively). Salsola Kali and mould were the most and the least prevalent individual allergens (72.5 % and 6.5 % respectively). Mean total IgE in patients with positive skin prick test was significantly higher than in patients without any positive skin prick test (308 vs 128 IU/mL, P = 0.016). 97 % of atopic patients were sensitised to Salsola kali and or Fraxinus americana. Our work showed the importance of weeds, especially the Amaranthaceae and Chenopodiaceae families. Diagnosis of pollen allergy can be simplified by using a combination of a few common aeroallergens.

Respiratory allergies are the most important public health issues in the world. They are caused by aeroallergens which play great role in pathogenesis of respiratory allergic diseases. The current study was conducted to evaluate the prevalence of positive skin test for various aeroallergens among allergic patients in Ahvaz, southwest Iran. 299 participants with allergic rhinitis (seasonal or perennial) were selected. Skin prick test using twenty three common allergen extracts was performed on all patients. The overall frequency of sensitization to any allergen was 85.6%. In outdoor allergens the most prevalent aeroallergen category was weeds (89%) followed by tree and grasses, and in indoor allergens, mites (43%) were the most prevalent aeroallergen. The mean and median numbers of positive test reactions among those with positive test responses were 11.5 and 13.0, respectively. 84% of patients were poly-sensitised and about 50% of them were sensitised to more than twelve different allergens. The results of the study revealed that prevalence of the skin prick reactivity to weed pollens is significant in southwest Iran and multiple sensitizations were common.

Background: The aim of this study was to evaluate the antimicrobial resistance and genetic basis for metronidazole (Mtz) and clarithromycin (Cla) resistance in strains of Helicobacter pylori, isolated from patients with gastroduodenal disorders. Patients and methods: A total of 157 H. pylori isolates (from 22 gastric cancer, 38 peptic ulcer disease, and 97 non-ulcer dyspepsia patients) were analyzed for drug susceptibility to Mtz and Cla, by gradient diffusion test (E-test, MAST). The PCR and sequence analysis of the rdxA and frxA for Mtz-resistant strains and the 23S rRNA for Cla-resistant strains were used to determine the genetic basis of drug resistance in H. pylori strains. Increased expression of TolC homologous genes (hefA) that upregulates efflux pump activity was determined in multidrug-resistant (MDR) strain of H. pylori by real-time PCR technique. Results: Among 157 H. pylori isolates, 32 (20.4%) strains were resistant to at least one of the antimicrobial agents. The highest resistance rate was attributed to Mtz (n=69, 43.94%). Among the resistant strains of H. pylori, 15 cases (9.55%) were detected as MDR. Mutations in the rdxA (85.5%) and A2143G point mutations (63.1%) in the 23S rRNA were the most common cause of resistance to Mtz and Cla in strains of H. pylori, respectively. In MDR strains, the rdxA mutation and A2143G-point mutation in the 23S rRNA were the most abundant mutations responsible for drug resistance. The relative expression of hefA in MDR strains (mean 3.706) was higher than the susceptible strains (mean 1.07). Conclusion: Mutational inactivation and efflux pump overexpression are two mechanisms that increase the resistance to H. pylori antimicrobial agents and the rate of MDR strains. In Iran, the mutations of rdxA and frxA in Mtz-resistant strains and A2143G and A2142G of the 23S rRNA in Cla-resistant strains were significant. The screening for these mutations could help to prevent antibiotic resistance, and to determine the most effective anti-H. pylori drugs.

The aim of this study was to report the characteristics and treatment strategies of all patients with acute bronchospasm who were presented to the emergency departments of Ahvaz, Iran, following the occurrence of a thunderstorm on November 2, 2013. A total of 2000 patients presenting with asthma attacks triggered by thunderstorm were interviewed and an initial questionnaire was completed for each individual. After twenty days, patients were asked to complete a supplementary questionnaire, but only 800 of them accepted to do so. The majority of subjects was aged 20–40 years (60.5%) and had no history of asthma in most cases (60.0%). The symptoms had started outdoors for 60.0% of the participants. In most patients, the onset of the condition was on November 2. Short-actingβ₂-agonist (salbutamol) and aminophylline were the most commonly prescribed medications in the emergency department. Upon the second interview, 85.3% of the patients were still symptomatic. Overall, 63.6% did not have a follow-up visit after hospital discharge, although all of them were referred to the specialist. The findings of the present study suggest that thunderstorm-associated asthma could affect young adults with no gender priority, with or without asthma history, which put a strain on emergency medical services.

Exposure to particulate matter (PM) can be considered as a factor affecting human health. The aim of this study was to investigate the concentration of PM_2.5 and heavy metals and their influence on survival of A549 human lung cells in exposure to PM_2.5 breathing air of Ahvaz city. In order to assess the levels of PM_2.5 and heavy metals, air samples were collected from 14 sampling stations positioned across Ahvaz city during both winter and summer seasons. The concentration of heavy metals was determined using ICP OES. Next, the MTT assay [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] was employed to ascertain the survival rate of A549 cells. The findings from this research demonstrated that average PM_2.5 of the study period was (149.5 μg/m³). Also, the average concentration of PM_2.5 in the urban area in winter and summer was (153.3- and 106.9 μg/m³) and in the industrial area this parameter was (191.6 and 158.3 μg/m³). The average concentration of metals (ng/m³) of urban areas against industrial, Al (493 vs. 485), Fe (536 vs. 612), Cu (198 vs. 212), Ni (128 vs. 129), Cr (48.5 vs. 54), Cd (118 vs. 124), Mn (120 vs. 119), As (51 vs. 67), Hg (37 vs. 50), Zn (302 vs. 332) and Pb (266 vs. 351) were obtained. The results of the MTT assay showed that the highest percentage of cell survival according to the exposure concentration was 25 > 50 > 100 > 200. Also, the lowest percentage of survival (58.8%) was observed in the winter season and in industrial areas with a concentration of 200 μg/ml. The carcinogenic risk assessment of heavy metals indicated that except for Cr, whose carcinogenicity was 1.32E−03, other metals were in the safe range (10^–4–10^–6) for human health. The high concentration of PM_2.5 and heavy metals can increase respiratory and cardiovascular diseases and reduce the public health level of Ahvaz citizens.