Lack of allergy to timothy grass pollen is not a passive phenomenon but associated with the allergen-specific modulation of immune reactivity.

BACKGROUND: Timothy grass (TG) pollen is a common seasonal airborne allergen associated with symptoms ranging from mild rhinitis to severe asthma. OBJECTIVE: The aim of this study was to characterize changes in TG-specific T cell responses as a function of seasonality. METHODS: Peripheral blood mononuclear cells (PBMCs) obtained from allergic individuals and non-allergic controls, either during the pollen season or out of season, were stimulated with either TG extract or a pool of previously identified immunodominant antigenic regions. RESULTS: PBMCs from allergic subjects exhibit higher IL-5 and IL-10 responses in season than when collected out of season. In the case of non-allergic subjects, as expected we observed lower IL-5 responses and robust production of IFN-γ compared to allergic individuals. Strikingly, non-allergic donors exhibited an opposing pattern, with decreased immune reactivity in season. The broad down-regulation in non-allergic donors indicates that healthy individuals are not oblivious to allergen exposure, but rather react with an active modulation of responses following the antigenic stimulus provided during the pollen season. Transcriptomic analysis of allergen-specific T cells defined genes modulated in concomitance with the allergen exposure and inhibition of responses in non-allergic donors. CONCLUSION AND CLINICAL RELEVANCE: Magnitude and functionality of T helper cell responses differ substantially in season vs. out of season in allergic and non-allergic subjects. The results indicate the specific and opposing modulation of immune responses following the antigenic stimulation during the pollen season. This seasonal modulation reflects the enactment of specific molecular programmes associated with health and allergic disease.

Exploring the characteristics of public reproductive health services in the Islamic Republic of Iran from the perspectives of unmarried women: what needs to be changed?

This qualitative study in the Islamic Republic of Iran aimed to explore facilitators and barriers to the use of reproductive health services by unmarried women. A purposive sample of unmarried women aged 25-60 years in Isfahan city were interviewed about their experiences of reproductive health services in public health centres. Content analysis of responses revealed that the favourable characteristics of reproductive health services in public centres were services that: were delivered by personnel of the same sex in a woman-friendly environment and available at a suitable price, and did not label clients. In contrast, the following characteristics made public health centres undesirable for unmarried women: not addressing single women for reproductive health services; lack of privacy; failure to maintain confidentiality; doubts about skills and scientific ability of personnel; and lack of integration of services.

PCR-based assay for the rapid and precise distinction of Pseudomonas aeruginosa from other Pseudomonas species recovered from burns patients.

BACKGROUND: Pseudomonas aeruginosa is an important lifethreatening nosocomial pathogen which plays a prominent role in wound infections in burns patients. We designed this study to identify the isolates of P. aeruginosa recovered from burns patients at the genus and species levels by means of primers targeting oprI and oprL genes. METHODS: During a 5-month period, wound samples were taken from burns patients and plated on MacConkey agar. All suspected colonies were screened for P. aeruginosa by means of a combination of phenotype tests. Specific primers for oprI and oprL genes were then used for the molecular identification of colonies. RESULTS: During the 5-month period, bacterial isolates recovered from burn wound infections were analyzed. Phenotype identification tests identified 171 (34.8%) P. aeruginosa isolates. However, molecular techniques that used species-specific primers to detect the amplicon of the oprL gene confirmed the exact identification of P. aeruginosa in only 133 cases; in the other isolates, the use of genus-specific primers detected the amplicon of the oprI gene, which confirmed the identification of fluorescent pseudomonads. CONCLUSIONS: This study indicates that molecular detection by means of an assay targeting the oprL gene is a useful technique for the rapid and precise detection of P. aeruginosa in burns patients. In addition to phenotype testing, PCR detection should be carried out in order to promptly ascertain the best aggressive antibiotic therapy for P. aeruginosa infections, thereby significantly improving clinical outcomes.

Flow-driven waves and phase-locked self-organization in quasi-one-dimensional colonies of Dictyostelium discoideum.

We report experiments on flow-driven waves in a microfluidic channel containing the signaling slime mold Dictyostelium discoideum. The observed cyclic adenosine monophosphate (cAMP) wave trains developed spontaneously in the presence of flow and propagated with the velocity proportional to the imposed flow velocity. The period of the wave trains was independent of the flow velocity. Perturbations of flow-driven waves via external periodic pulses of the signaling agent cAMP induced 1∶1, 2∶1, 3∶1, and 1∶2 frequency responses, reminiscent of Arnold tongues in forced oscillatory systems. We expect our observations to be generic to active media governed by reaction-diffusion-advection dynamics, where spatially bound autocatalytic processes occur under flow conditions.

Positively charged imidazolium-based ionic liquid-protected silver nanoparticles: a promising disinfectant in root canal treatment.

AIM: To synthesize and characterize silver nanoparticles (Ag NPs) with different surface charges in order to evaluate their cytotoxicity and antibacterial activity in the absence and presence of dentine compared with NaOCl and CHX. METHODOLOGY: Ag NPs with positive, negative and neutral surface charges were synthesized and characterized. The first phase of the experiment determined the minimum inhibitory concentrations (MICs) of NPs against planktonic E. faecalis and compared them with that of NaOCl and CHX. The second phase tested the elimination of E. faecalis at different contact times (5, 20 and 60 min and 4 and 24 h), and the role of dentine in their inactivation was assessed. In the third phase, the most effective Ag NP solution was selected for cytocompatibility assessment. An MTT-based cytotoxicity assay was used to evaluate the cytotoxicity of the selected NP solution in different concentrations on L929 fibroblasts compared to that of 2.5% NaOCl and 0.2% CHX. Student's t-test and repeated measures manova approach were used for statistical analyses. RESULTS: The characterization revealed synthesis of colloidal NPs in the size range of 5-10 nm in diameter. The results indicated that Ag NP with a positive surface charge had the smallest MIC against planktonic E. faecalis, and it was active in very lower concentrations compared to NaOCl, CHX and the other tested AgNPs. Positive-charged Ag NPs at 5.7 × 10(-10)  mol L(-1) completely prevented the growth of E. faecalis after 5 min of contact time, a finding comparable to 0.025% NaOCl. Dentine powder had variable inhibitory effects on all tested materials after 1 h incubation period, but after 24 h, NaOCl and the positive-charged Ag NPs were not inhibited by dentine at any concentration used. CHX was the most and the positively charged Ag NP solution was the least toxic solutions to L929 fibroblasts (P < 0.001). CONCLUSIONS: Ag NP surface charge was important in bactericidal efficacy against E. faecalis. The positively charged imidazolium-based ionic liquid-protected Ag NPs showed promising antibacterial results against E. faecalis and exhibited a high level of cytocompatibility to L929 cells.

Birth weight and risk of childhood acute leukaemia.

Studies of risk factors for acute leukaemia are inconclusive. This case-control study was done in West Azerbaijan province, Islamic Republic of Iran, to determine the relationship between birth weight and acute leukaemia in children aged under 15 years. For every patient 2 age- and sex-matched controls were selected from hospital and community populations. Of 130 cases diagnosed over the period 2003-2009,108 (83.1%) had lymphoblastic and 22 (16.9%) myloblastic type. Significantly more of them were male than female (55.4% versus 44.6%). In a multivariate logistic regression model variables significantly associated with acute leukaemia were: birth weight (OR = 2.25), birth order (OR = 2.25), birth place (OR = 7.93), history of chickenpox (OR = 0.46) and mothers' education (OR = 3.23). The risk of acute leukaemia increased significantly with increasing birth weight in the total group and among girls, but not among boys.

In vitro effects of several surface preparation methods on shear bond strength of orthodontic brackets to caries-like lesions of enamel.

AIM: The aim of this study was to evaluate the efficiency of several surface preparation methods for improving shear bond strength of brackets to demineralised enamel. STUDY DESIGN: in vitro study. Eighty premolars were selected and divided into 5 groups. Group 1 served as the control, while the remaining 4 groups were immersed in a demineralising solution (pH 4.8) for 12 weeks. In groups 1 (control) and 2 (demineralised/control) conventional acid etching was used. In group 3, a solution of 5% sodium hypochlorite (NaOCl) was applied on enamel surface for one minute after acid etching. The brackets in group 4 were bonded with Transbond Plus self-etching primer, and group 5 underwent treatment with a 2% sodium fluoride (NaF) gel, which was applied on the enamel surface for 4 minutes before etching. Shear bond strength (SBS) and adhesive remnant index (ARI) were determined in all groups, and surface morphology was examined under scanning electron microscope (SEM). RESULTS: The mean SBS of acid-etched demineralised enamel was significantly lower than that of acid-etched sound enamel (p<0.05). Treatment of caries-like lesions with 5% NaOCl or self-etching primer failed to improve the bond strength. After NaF treatment and acid etching of demineralised enamel, both type 1 and type 2 etching patterns were observed and the resulting SBS was comparable to that of sound enamel (p>0.05). CONCLUSION: The application of 2% NaF on enamel caries before bracket bonding is an effective way for enhancing the bond strength.

Fabrication and Characterization of a Nanofast Cement for Dental Restorations.

This study was aimed at fabricating and evaluating the physical and bioproperties of nanofast cement (NFC) as a replacement of the MTA. The cement particles were decreased in nanoscale, and zirconium oxide was used as a radiopacifier. The setting time and radiopacity were investigated according to ISO recommendations. Analysis of color, bioactivity, and cytotoxicity was performed using spectroscopy, simulated body fluid (SBF), and MTT assay. The setting time of cement pastes significantly dropped from 65 to 15 min when the particle sizes decreased from 2723 nm to 322 nm. Nanoparticles provide large surface areas and nucleation sites and thereby a higher hydration rate, so they reduced the setting time. Based on the resulting spectroscopy, the specimens did not exhibit clinically noticeable discoloration. Resistance to discoloration may be due to the resistance of zirconium oxide to decomposition. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and infrared spectroscopy (FTIR) examinations of the immersed SBF samples showed apatite formation that was a reason for its suitable bioactivity. The results of cell culture revealed that NFC is nontoxic. This study showed that NFC was more beneficial than MTA in dental restorations.

Tomato (Lycopersicon esculentum L.) nutrient and lead uptake affected by zeolite and DTPA in a lead-polluted soil.

Development of alleviation strategies, which enhance plant growth under heavy metal stress, is important. Inorganic (zeolite) and organic (diethylene triamine penta-acetic acid, DTPA) amendments affecting the alleviation of lead (Pb) stress in a calcareous soil were tested by investigating leaf nutrient uptake of tomato (Lycopersicon esculentum L.) plants. Experimental quantities of lead (Pb) at 0, 50, 100 and 150 mg·kg-1 soil, zeolite (clinoptilolite) at 0%, 0.5% and 1%, and DTPA at 0, 50 and 100 mg·kg-1 soil were tested in a factorial experiment with three plant replicates. According to the anova, Pb, zeolite, DTPA and their interactions significantly affected plant concentrations of nitrogen (N), potassium (K), iron (Fe), zinc (Zn), copper (Cu), manganese (Mn) and lead (Pb). With increasing DTPA concentration at different levels of zeolite and Pb, plant concentrations of macro- and micronutrients significantly increased. Increasing soil Pb increased leaf Pb concentration and decreased the uptake of N, K, Fe, Zn, Cu and Mn. Although with increasing Pb concentration the uptake of macro- and micronutrients decreased in tomato, the use of zeolite and DTPA alleviated this stress by increasing nutrient uptake compared to the control. Interestingly, however, increased levels of zeolite and DTPA led to a decreased uptake of nutrients by plants (compared with control), indicating the absorption of such nutrients by the two amendments and their partial release for further plant use. Zeolite and DTPA may alleviate the negative effects of soil Pb on tomato growth by decreasing nutrient leaching and increasing plant nutrient uptake.

Association of vitamin D with the modulation of the disease severity in COVID-19.

In late 2019, SARS-CoV-2 started to spread throughout the world causing the COVID-19 that has taken a considerable number of lives. Results obtained from several investigations have explained the virus origin, pathogenicity, and transmission. Similar to SARS coronavirus, the pulmonary angiotensin converting enzyme (ACE) 2 was introduced as the virus receptor for entering the cell. An increased body of epidemiological and clinical evidences has shown modulating effects of vitamin D in lung injuries through several mechanisms. Several clinical symptoms as well as molecular factors have shown to be related to the disease transmission and severity. In this study, vitamin D, ACE concentrations, and neutrophil to lymphocyte ratio (NLR) were measured in patients with confirmed COVID-19 in comparison with control group. Results demonstrated significant alterations in vitamin D and ACE levels as well as NLR in the patients' group. Contribution of those factors with the prognosis and severity of the disease has been shown.

The Middle East and Eastern Europe rabies Expert Bureau (MEEREB) third meeting: Lyon-France (7-8 April, 2015).

MEEREB is an inter-regional network of countries from North Africa, Europe, the Middle East and Central Asia that work together with the aim of improving rabies control and prevention at local, regional and global level. MEEREB members met for the third time in 2015 in France (Lyon) to review the current rabies situation within the network and to discuss the way forward the prospect of a One Health approach against rabies. Dogs were the main vector of transmission in all MEEREB countries except for Croatia and Serbia where foxes represented the primary source. The number of rabies animal cases reported in 2014 varied substantially between countries with Ukraine reporting the highest number of animal cases. Human cases still occur in North Africa and all Middle East and Eurasian countries while no cases of human rabies were reported in Croatia, Serbia and Romania, although cases of rabies were identified in both dogs and foxes in 2014. Participants concluded that MEEREB can act as a think-tank where countries can share data, information, experiences and best practices to jointly address challenges in rabies control and prevention. They called for elimination of dog-transmitted rabies through vaccine and rabies immunoglobulin stockpiles and implementation of a One Health approach to achieve rabies's eradication.

Improved microstructure and mechanical properties in gas tungsten arc welded aluminum joints by using graphene nanosheets/aluminum composite filler wires.

In the present study, different amounts of graphene nanosheets (GNSs) were added to the 4043 aluminum alloy powders by using the mechanical alloying method to produce the composite filler wires. With each of the produced composite filler wires, one all-weld metal coupon was welded using the gas tungsten arc (GTA) welding process. The microstructure, mechanical properties and fracture surface morphology of the weld metals have been evaluated and the results are compared. As the amount of GNSs in the composition of filler wire is increased, the microstructure of weld metal was changed from the dendritic structure to fine equiaxed grains. Furthermore, the tensile strength and microhardness of weld metal was improved, and is attributed to the augmented nucleation and retarded growth. From the results, it was seen that the GNSs/Al composite filler wire can be used to improve the microstructure and mechanical properties of GTA weld metals of aluminum and its alloys.

Screening plant growth promoting rhizobacteria for improving seed germination, seedling growth and yield of maize.

The effect of Plant Growth-Promoting Rhizobacteria (PGPR) on seed germination, seedling growth and yield of field grown maize were evaluated in three experiments. In these experiments six bacterial strains include P. putida strain R-168, P. fluorescens strain R-93, P. fluorescens DSM 50090, P. putida DSM291, A. lipoferum DSM 1691 and A. brasilense DSM 1690 were used. Results of first study showed seed inoculation significantly enhanced seed germination and seedling vigour of maize. In second experiment, leaf and shoot dry weight and also leaf surface area significantly were increased by bacterial inoculation in both sterile and non-sterile soil. The results showed that inoculation with bacterial treatments had a more stimulating effect on growth and development of plants in nonsterile than sterile soil. In the third experiment, Inoculation of maize seeds with all bacterial strains significantly increased plant height, 100 seed weight, number of seed per ear and leaf area. The results also showed significant increase in ear and shoot dry weight of maize.

Effect of sulphur fertilization on breadmaking quality of three winter wheat varieties.

For study of the effect of sulphur and nitrogen on breadmaking quality of three varieties of wheat, four field experiments were carried out at four sites in north and northeast of Iran. This research carried out as factorial experiment based on randomized complete block design with three factors and four replications. Factors to be studied were, wheat varieties of Tajan, Falat, Sardari and sulphur at the rate of 0, 20 and 80 kg ha(-1) in the form of gypsum and nitrogen at two rate of 180 and 230 kg ha(-1) in the form of urea. Results showed that sulphur increased the loaf volume significantly and decreased the N:S ratio in grain. Grain S concentration had high correlation coefficient with grain protein percent. Sulphur increment caused increase in loaf volume, better breadmaking quality, which may be due to gluten in protein. Nitrogen fertilizer application increased protein concentration of grain, but it had no significant effect on loaf volume.

Improving wheat grain yield under water stress by stem hydrocarbon reserve utilization.

Current assimilation and remobilization of dry matter during grain filling in wheat subjected to different levels of water deficit during phenological growth stage. The experiment was conducted as split plot. Time of water stress and levels considered as main and sub plots, respectively. water stress treatments exposed at jointing, anthesis and seed filling stage and levels of water stress include, Full Irrigation (FI), Low Water Stress (LWS), Moderate Water Stress (MWS) and High Water Stress (HWS). Grain yield and dry matter accumulation and remobilization were negatively affected by water stress. The lowest grain yield was obtained from HWS and when water stress occurred at anthesis. Dry matter accumulation at LWS was 4.87%, at MWS was 14.86% and at HWS was 26.55% lower than FI, respectively. Spike density and the number of kernel per spike were affected similarly and decreased with water deficit increased. The decrease in the number of spikes per unit area due to LWS, MWS and HWS was 13, 23 and 30% compared to FI, respectively. As the water stress was imposed at jointing stage, the lowest number of spikes per unit area and when imposed at anthesis, the lowest number of kernel per spike was obtained. With increase in water stress intensity, the contribution of mobilized DM (DMRC) to grain yield increased. The highest DMRC value obtained from HWS with 25.37%.

The effect of lidocaine and sufentanil in preventing intraocular pressure increase due to succinylcholine and endotracheal intubation.

BACKGROUND AND OBJECTIVE: Succinylcholine administration, laryngoscopy and tracheal intubation are followed by increased intraocular pressure. Various premedications have been advocated for preventing increases in intraocular pressure, especially in patients undergoing surgical repair of open globe due to penetrating eye trauma. Results of studies in this area have been controversial. METHODS: In this double-blind study, three groups of 70 patients receiving sufentanil, lidocaine and placebo 90 s prior to intubation were evaluated and compared for intraocular pressure changes following succinylcholine administration, laryngoscopy and tracheal intubation. RESULTS: Mean intraocular pressure measured 2 and 3 min after succinylcholine administration in groups receiving sufentanil and lidocaine was significantly lower than in the placebo group. Mean intraocular pressure changes in the three groups were -1.84, -2.03 and +2.82 mmHg, respectively in minute 2; -4.78, -4.73 and +1.35 mmHg, respectively in minute 5. There was a significant intraocular pressure decrease in the sufentanil and lidocaine groups, compared to the placebo group. The eye surgeons' satisfaction was also significantly higher with the sufentanil and lidocaine groups. CONCLUSION: Previous studies have yielded controversial results as to the effect of sufentanil and lidocaine in preventing intraocular pressure following succinylcholine administration, laryngoscopy and tracheal intubation. The present study affirms the preventive effect of these drugs on intraocular pressure increase.

Determination of very low levels of dissolved mercury(II) and methylmercury in river waters by continuous flow with on-line UV decomposition and cold-vapor atomic fluorescence spectrometry after pre-concentration on a silica gel-2-mercaptobenzimidazol sorbent.

A new, simple and sensitive method for the simultaneous determination of mercury(II) and methylmercury chloride at sub-ng l(-1) levels in river waters is described. Inorganic and organic mercury were preconcentrated from fresh water samples simultaneously on a laboratory-made column containing 2-mercaptobenzimidazol loaded on silica gel and then quantitatively eluted with 0.05 M KCN solution and 2.0 M HCl to desorp inorganic and methylmercury species, respectively. After irradiation with an intensive UV source, MeHg(+) was decomposed and mercury vapours were generated from inorganic and organic mercury using an acidic SnCl(2) solution in a continuous flow system and were subsequently determined with a cold vapour atomic fluorescence (CV-AFS) spectrometer. Detection limits (3sigma) were 0.07 and 0.05 ng l(-1) (as Hg) for mercury(II) chloride and methylmercury chloride, respectively. Relative standard deviations of method (%R.S.D.) were 8.8 and 10 for inorganic and organomercuric species in the river water, respectively. The analysis of real samples, taken from different rivers, showed that inorganic mercury levels ranged from 4.0+/-0.6 to 12+/-1 ng l(-1) (as Hg and 95% confidence limit) and methylmercury levels at 0.2+/-0.02 ng l(-1)(as Hg).