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61.
Background:Allergic disorders are common health problems worldwide with significant socio-economic impacts. The best diagnostic method using allergenic extract is the skin prick test. Regarding the effects of geo-climatic factors and allergenic extract source material quality, the aim of study was to determine the safety and efficacy of some in-house-developed allergenic extracts.Methods:Forty-five different allergenic extracts, including common regional pollen, foods, and dog and cat hair, as well as positive and negative extracts, were prepared from domestic sources using optimum extraction methods. All extracts passed stability and sterility testing, and sterile final products containing 50% glycerin in 10 and 20 w/v concentrations were used. Skin prick testing was performed on volunteers and immediate or late side effects were recorded. Results:In total, 56 students (mean age: 21.2±2.3y, M/F ratio: 1.07) participated in this study. For inhalant allergens, all extracts except dog hair extract caused positive responses. Salsola kali (Russian thistle) and Fraxinus velutina (ash tree) were the most common grass and tree pollen extracts, respectively. Of 18 different food extracts, five, including egg white, tomato, fig, melon, and green pepper caused skin reactivity in only one person. No participant reported any immediate or late side effects, including large local reaction or systemic response.Conclusion:The result of the current study confirmed the safety of all our in-house-developed allergenic extracts. Regarding efficacy, almost all inhalant and five food allergens caused positive skin responses.Key Words: Allergenic extract, In-house extract, Skin prick test  相似文献   
62.
To assess the potential of Pb+2 accumulation in different parts of Acacia victoria, one year old A. victoria seedlings were exposed to Pb2+(NO3)2 in 5 different concentrations: 0, 50, 250, 500 and 1000 (mg Pb2+ L?1) for 45 days. Subsequently, Pb2+ uptake was quantified in roots, shoots and leaves of the seedlings by Atomic Absorption Spectroscopy (AAS). In addition, some physiological parameters such as biomass production, shoots and roots length, plant appearance, tissue concentrations and chlorophyll content were examined. Tissue concentrations increased as Pb2+ concentration increased for A. victoria. The visible toxicity symptoms (chlorosis and necrosis) appeared only to the highest concentration (1000 mg Pb2+ L?1), resulting in photosynthesis decrease, plant height, root length and dry biomass reduction. Almost 70% (up to 3580 mg Kg?1 of dry tissue) from the Pb2+ was accumulated in the entire plant tissues was retained in the roots in the seedlings exposed to 1000 mg Pb2+ L?1. The seedlings accumulated between 403 to 913 mg Kg?1 of Pb2+ in shoots and 286 to 650 mg Kg?1 of Pb2+ in leaves at different treatments. Bioconcentration and translocation factors were determined 5.14 and 0.255, respectively. The results show that A. victoria is suitable for lead-phytostabilization in Pb2+-contaminated soil.  相似文献   
63.
64.
During radiotherapy, ionizing irradiation interacts with biological systems to produce free radicals, which attacks various cellular components. The hematopoietic system is well-known to be radiosensitive and its damage may be life-threatening. Melatonin synergistically acts as an immunostimulator and antioxidant. In this study we used a total of 120 rats with 20 rats in each group. Group 1 did not receive melatonin or irradiation (Control group), Group 2 received only 10 mg/kg melatonin (Mel group), Group 3 exposed to dose of 2 Gy irradiation (2 Gy Rad group), Group 4 exposed to 8 Gy irradiation (8 Gy Rad group), Group 5 received 2 Gy irradiation plus 10 mg/kg melatonin (Mel +2 Gy Rad group) and Group 6 received 8 Gy irradiation plus 10 mg/kg melatonin (Mel+8 Gy Rad group). Following exposure to radiation, five rats from each group were sacrificed at 4, 24, 48 and 72 h. Exposure to different doses of irradiation resulted in a dose-dependent decline in the antioxidant enzymes activity and lymphocyte count (LC) and an increase in the nitric oxide (NO) levels of the serum. Pre-treatment with melatonin (10 mg/kg) ameliorates harmful effects of 2 and 8 Gy irradiation by increasing lymphocyte count(LC) as well as antioxidant enzymes activity and decreasing NO levels at all time-points. In conclusion 10 mg/kg melatonin is likely to be a threshold concentration for significant protection against lower dose of 2 Gy gamma irradiation compared to higher dose of 8 Gy. Therefore, it seems that radio-protective effects of melatonin are dose-dependent.  相似文献   
65.
The Irano-Turanian floristic region is a major center of endemism in the Holarctic of Eurasia. The Alborz Mountains of northern Iran are a complex and heterogeneous environmental system with rich water resources and great habitat diversity. We have investigated steppe plant communities along an altitudinal gradient ranging from approximately 1,000 m a.s.l. in the semi-desert steppes near Tehran to a height of 3,966 m a.s.l. at the summit of Mount Tochal. Our two-way indicator species analysis of 1,069 vegetation samples resulted in classification of five major vegetation zones: (1) a semi-desert Artemisia steppe near Tehran, (2) a Stipa grassland in the alluvial undulating hills north and west of Tehran, (3) a submontane and steppe zone, (4) a subalpine cushion formation zone and (5) an alpine meadow and subnival zone of Mount Tochal. Annuals and ephemerals in the semi-desert vegetation decline as altitude increases and almost disappear in the alpine zone. Past human impacts of ancient Persian civilization and a traditional pastoral economy have affected the physiognomy of plant communities; thorny dwarf shrubs now dominate the treeless vegetation of the region. Lower competition for space, different phenology and the presence of edaphic and hydrological layers associated with anthropogenic impacts are major reasons for entanglement of different plant communities in the arid- and semi-arid steppe. The phytogeography of the region changes from omni-Irano-Turanian and Saharo-Sindian transgressive species at lower altitudes to a more limited range of western Irano-Turanian species and local endemics at higher altitudes.  相似文献   
66.
Protein antigens have drawn a lot of attention from investigators working on tuberculosis vaccines. These proteins can be used to improve the immunogenicity of the new generation BCG vaccines or even replace them completely. Recombinant technology is used to insure the production of pure mycobacterial antigens in high quantities. Mycolyl transferase 85B (Ag85B) is a potent, mycobacterial antigen that significantly stimulates immune responses. Since Ag85B is an apolar protein, production of the water-soluble antigen is of interest. In this work, we report a systematic optimization strategy concerning cloning systems and purification methods, aiming at increasing the yield of recombinant Ag85B. Our optimized method resulted in a yield of 8 mg of recombinant Ag85B from 1 liter of induced culture (400 μg/ml) by using pET32a(+), Escherichia coli Rosseta-gami?(DE3) pLysS and a Ni–NTA agarose-based procedure and on-column re-solubilization. The purified recombinant Ag85B showed strong immunostimulating properties by inducing high levels of TNF-α, IFN-γ, IL-12, and IgG2a in immunized mice, therefore it can effectively be applied in TB vaccine researches.  相似文献   
67.
The non-integrin laminin receptor (LAMR1/RPSA) and galectin-3 (Gal-3) are multi-functional host molecules with roles in diverse pathological processes, particularly of infectious or oncogenic origins. Using bimolecular fluorescence complementation and confocal imaging, we demonstrate that the two proteins homo- and heterodimerize, and that each isotype forms a distinct cell surface population. We present evidence that the 37 kDa form of LAMR1 (37LRP) is the precursor of the previously described 67 kDa laminin receptor (67LR), whereas the heterodimer represents an entity that is distinct from this molecule. Site-directed mutagenesis confirmed that the single cysteine (C173) of Gal-3 or lysine (K166) of LAMR1 are critical for heterodimerization. Recombinant Gal-3, expressed in normally Gal-3-deficient N2a cells, dimerized with endogenous LAMR1 and led to a significantly increased number of internalized bacteria (Neisseria meningitidis), confirming the role of Gal-3 in bacterial invasion. Contact-dependent cross-linking determined that, in common with LAMR1, Gal-3 binds the meningococcal secretin PilQ, in addition to the major pilin PilE. This study adds significant new mechanistic insights into the bacterial–host cell interaction by clarifying the nature, role and bacterial ligands of LAMR1 and Gal-3 isotypes during colonization.  相似文献   
68.
Habrobracon hebetor Say is one of the most important ectoparasitoids of the larval stage of many invasive agricultural pests such as noctuid and pyralid moths. Lethal and sublethal effects of carbaryl and abamectin were assessed on the ectoparasitoid H. hebetor in laboratory conditions. Dose–response bioassays were carried out on immature and adult stages by using dipping and contact residue methods, respectively. LC50 (lethal concentration for 50%) values of carbaryl and abamectin were 31.19 and 4.16 mg a.i. l−1 on larval stage and 12.6 and 4.42 mg a.i. l−1 on adults, respectively. In order to assess the sublethal effects, adult wasps were exposed to an LC30 of each insecticide and then the demographic parameters of live wasps were studied. The results showed that the intrinsic rate of increase (r m ), finite rate of increase (λ), net reproductive rate (R0) and gross reproductive rate (GRR) were significantly affected by the insecticides. The highest and the lowest r m values were 0.23 and 0.17 in control and carbaryl-treated insects, respectively. The sex ratio of H. hebetor offspring was not significantly affected by either insecticide. The results showed that carbaryl had more adverse effects on population parameters of the parasitoid compared to abamectin. Field studies are needed to determine the total effects of the pesticides on H. hebetor.  相似文献   
69.
Given the conflicting results about the positive effects of magnesium and l-carnitine and as there is no report concerning concurrent supplementation of magnesium and l-carnitine on migraine prophylaxis, the effects of magnesium, l-carnitine, and concurrent magnesium?Cl-carnitine supplementation on migraine indicators were assessed. In this clinical trial, 133 migrainous patients were randomly assigned into three intervention groups: magnesium oxide (500?mg/day), l-carnitine (500?mg/day), and Mg?Cl-carnitine (500?mg/day magnesium and 500?mg/day?l-carnitine), and a control group. After 12?weeks of supplementation, the checklist of migraine indicators including migraine attacks/month, migraine days/month, and headache severity was completed, and serum concentrations of magnesium and l-carnitine were measured by atomic absorption spectrophotometry and enzymatic UV test, respectively. The results showed a significant reduction in all migraine indicators in all studied groups (p?<?0.05). The ANOVA results showed a significant reduction in migraine frequency across various supplemented and control groups (p?=?0.008). By separating the effects of magnesium supplementation from other confounding factors such as routine treatments using the repeated measures and nested model, it was clarified that magnesium supplementation had a significant effect on all migraine indicators. Oral supplementation with magnesium oxide and l-carnitine and concurrent supplementation of Mg?Cl-carnitine besides routine treatments could be effective in migraine prophylaxis; however, larger trials are needed to confirm these preliminary findings.  相似文献   
70.
Here, we report a structure-based virtual screening of the ZINC database (containing about five million compounds) by computational docking and the analysis of docking energy calculations followed by in vitro screening against H. pylori urease enzyme. One of the compounds selected showed urease inhibition in the low micromolar range. Barbituric acid and compounds 1a, 1d, 1e, 1f, 1g, 1h were found to be more potent urease inhibitors than the standard inhibitor hydroxyurea, yielding IC(50) values of 41.6, 83.3, 66.6, 50, 58.8, and 60 μM, respectively (IC(50) of hydroxyurea = 100 μM). 5-Benzylidene barbituric acid has enhanced biological activities compared to barbituric acid. Furthermore, the results indicated that among the substituted 5-benzylidene barbiturates, those with para substitution have higher urease inhibitor activities. This may be because the barbituric acid moiety is closer to the bimetallic nickel center in unsubstituted or para-substituted than in ortho- or meta-substituted analogs, so it has greater chelating ability.  相似文献   
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