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111.
The silverleaf whitefly is one of the most important pests found commonly in Iran and in the world. The development of alternative methods instead of chemical applications is necessary in pest management for human health and environment protection. The objective of this research was to assess the effects of extracts of two medicinal plant species: Calotropis procera and Allium sativum, and a formulation containing azadirachtin on fecundity and fertility of the silverleaf whitefly, grown on greenhouse tomato plants. The effects were compared to that of pymetrozine, a synthetic insecticide. According to the results, there was a significant difference among treatments for all reproductive parameters. Gross fecundity rates for pesticides control, herbal extract control, C. procera extract, A. sativum extract, azadirachtin and pymetrozine were 184.75, 146.72, 80.11, 82.18, 63.06 and 55.96 eggs, respectively. These herbal extracts were effective against this pest and they can be the suitable choices for replacing these chemical insecticides.  相似文献   
112.
Dubas bug, Ommatissus lybicus is one of the major sucking pests of date palm. Data palm is the most important economic crop in Iran. In this research, we isolated the pathogenic strain KB 201, KB 206, KB 211, KB 215, KB 220 and KB 512, of entomopathogenic fungi Beauveria bassiana from soil and insects, which produced aerial and submerged conidia and blastospores in the laboratory conditions. We investigated the best conditions for the production and utilisation of the spore suspension to spray the nymph of O. lybicus, which is one of the important pests in Kerman province (Iran). A total of 180 isolates that naturally infected by O. lybicus were collected from date palm in Kerman province during spring and summer seasons 2010–2011. The pathogen city test was carried out with direct spray. To bioassay the isolates, three concentrations of the spore suspension were prepared as follows: 1?×?106, 1?×?107 and 1?×?108?conidia/ml. The pests were sprayed by aerial conidial suspension, which was prepared by 0.01% Tween 80 in distilled water, and the controls were sprayed by 0.01% Tween 80in distilled water. After spraying the pests, the plates were incubated at 25?±?1?°C and 80% of relative humidity. Then, the treated pests were monitored every day for the fungal growth and mortality.  相似文献   
113.
The first purpose of our study was to determine culturable indoor airborne fungi in different places in Ahvaz during normal and dust event days. Ahvaz is the biggest city in southwest of Iran which has suffered from dust storms in recent decade. To minimize personal exposure to polluted air, governmental and private sectors excluding critical places such as hospitals, fire department and security organization are closed during dust event days. Therefore, the second objective of this survey was to see whether this plan (forced shutdown) is in place. Samples were collected from July 2010 to March 2011 by using quick take 30 equipped with a single-stage sampler. Fungal population was measured in school, university and hospital during normal and dust event days. Five dominant fungi genera in three sampling stations were Cladosporium, Alternaria, Aspergillus, Penicillium and Rhizopus the concentrations (CFU/m3) of which were higher during dust events than normal days. Airborne fungi such as Aspergillus, Mucor and Rhizopus are opportunistic fungi which can cause aspergillusis and mucormycosis infections in immunodeficiency individuals, vulnerable groups as well as healthy people. The results of this study confirmed the measure of forced shutdown in Ahvaz city due to increased concentration of fungi during dust event days.  相似文献   
114.
Cytokines play an important role in the pathophysiology of traumatic brain injury (TBI). This study was designed to determine the effects of administering progesterone (P) and estrogen (E), alone and in combination, on brain water content, blood-brain barrier (BBB) disturbance, and brain level of cytokines following diffuse TBI. Ovariectomized rats were divided into 9 groups, treated with vehicle, E1, E2, P1, P2, E1+P1, E1+P2, E2+P1, and E2+P2. Levels of BBB disruption (5 h), cytokines, and water content (24 h) were evaluated after TBI induced by the Marmarou method. Physiological (E1 and P1) and pharmacological (E2 and P2) doses of estrogen and progesterone were administered 30 min after TBI. Water content in the E1+P2-treated group was higher than in the E1-treated group. The inhibitory effect of E2 on water content was reduced by adding progesterone. The inhibitory effect of E1 and E2 on Evans blue content was reduced by treatment with E1+P1 and E2+P2, respectively. The brain level of IL-1β was reduced in E1 and E2, after TBI. In the E2+P2-treated group, this level was higher than in the E2-treated group. The brain level of TGF-β was also elevated by the administration of progesterone and estrogen alone, and reduced when the hormones were administered in combination. In conclusion, a combined administration of progesterone and estrogen inhibited the decreasing effects of administration of progesterone and estrogen alone on water content and BBB disruption that mediated to change the proinflammatory cytokines.  相似文献   
115.
Mental retardation (MR) has a worldwide prevalence of around 2% and is a frequent cause of severe disability. Significant excess of MR in the progeny of consanguineous matings as well as functional considerations suggest that autosomal recessive forms of MR (ARMR) must be relatively common. To shed more light on the causes of autosomal recessive MR (ARMR), we have set out in 2003 to perform systematic clinical studies and autozygosity mapping in large consanguineous Iranian families with non-syndromic ARMR (NS-ARMR). As previously reported (Najmabadi et al. in Hum Genet 121:43-48, 2007), this led us to the identification of 12 novel ARMR loci, 8 of which had a significant LOD score (OMIM: MRT5-12). In the meantime, we and others have found causative gene defects in two of these intervals. Moreover, as reported here, tripling the size of our cohort has enabled us to identify 27 additional unrelated families with NS-ARMR and single-linkage intervals; 14 of these define novel loci for non-syndromic ARMR. Altogether, 13 out of 39 single linkage intervals observed in our cohort were found to cluster at 6 different loci on chromosomes, i.e., 1p34, 4q27, 5p15, 9q34, 11p11-q13 and 19q13, respectively. Five of these clusters consist of two significantly overlapping linkage intervals, and on chr 1p34, three single linkage intervals coincide, including the previously described MRT12 locus. The probability for this distribution to be due to chance is only 1.14 × 10(-5), as shown by Monte Carlo simulation. Thus, in contrast to our previous conclusions, these novel data indicate that common molecular causes of NS-ARMR do exist, and in the Iranian population, the most frequent ones may well account for several percent of the patients. These findings will be instrumental in the identification of the underlying genes.  相似文献   
116.
Molecular Biology Reports - The underlying mechanism involved in the onset of many diseases such as diabetes is oxidative stress. Zataria multiflora has a very high antioxidant power that can be...  相似文献   
117.
Cancer is one of main health public problems worldwide. Several factors are involved in beginning and development of cancer. Genetic and internal/external environmental factors can be as important agents that effect on emerging and development of several cancers. Diet and nutrition may be as one of important factors in prevention or treatment of various cancers. A large number studies indicated that suitable dietary patterns may help to cancer prevention or could inhibit development of tumor in cancer patients. Moreover, a large numbers studies indicated that a variety of dietary compounds such as curcumin, green tea, folat, selenium, and soy isoflavones show a wide range anti‐cancer properties. It has been showed that these compounds via targeting a sequence of cellular and molecular pathways could be used as suitable options for cancer chemoprevention and cancer therapy. Recently, dietary microRNAs and exosomes have been emerged as attractive players in cancer prevention and cancer therapy. These molecules could change behavior of cancer cells via targeting various cellular and molecular pathways involved in cancer pathogenesis. Hence, the utilization of dietary compounds which are associated with powerful molecules such as microRNAs and exosomes and put them in dietary patterns could contribute to prevention or treatment of various cancers. Here, we summarized various studies that assessed effect of dietary patterns on cancer prevention shortly. Moreover, we highlighted the utilization of dietary compounds, dietary microRNAs, and dietary exosomes and their cellular and molecular pathways in cancer chemoprevention.  相似文献   
118.
DNA binding studies of flavonoids are needed to understand the reaction mechanism and improve drugs that target DNA. Quercetin (Q) is one of the most common flavonoids that can chelate metal ions and interact with double-stranded DNA. In the present work, UV absorption spectrophotometry, viscosimetry, circular dichroism, and fluorescence spectroscopic techniques were employed to study the interaction of water-soluble quercetin--molybdenum(VI) complex [Q-Mo(VI)] with calf thymus DNA. The binding constants (K(b)) for the complex with DNA were estimated to be 2.9?×?10(3) through spectroscopic titrations. Upon addition of the complex, significant decreases were observed in the viscosity of calf thymus DNA. Circular dichroic spectra indicated that there are certain detectable conformational changes in the DNA double helix when complex was added. Further, competitive methylene blue binding studies with fluorescence spectroscopy have shown that the complex can bind to DNA through nonintercalative mode. The experimental results suggest that Q-Mo(VI) binds to DNA via an outside binding mode.  相似文献   
119.
EGFR signaling plays a very important role in NSCLC. It activates Ras/ERK, PI3K/Akt and STAT activation pathways. These are the main pathways for cell proliferation and survival. We have developed two mathematical models to relate to the different EGFR signaling in NSCLC and normal cells in the presence or absence of EGFR and PTEN mutations. The dynamics of downstream signaling pathways vary in the disease state and activation of some factors can be indicative of drug resistance. Our simulation denotes the effect of EGFR mutations and increased expression of certain factors in NSCLC EGFR signaling on each of the three pathways where levels of pERK, pSTAT and pAkt are increased. Over activation of ERK, Akt and STAT3 which are the main cell proliferation and survival factors act as promoting factors for tumor progression in NSCLC. In case of loss of PTEN, Akt activity level is considerably increased. Our simulation results show that in the presence of erlotinib, downstream factors i.e. pAkt, pSTAT3 and pERK are inhibited. However, in case of loss of PTEN expression in the presence of erlotinib, pAkt level would not decrease which demonstrates that these cells are resistant to erlotinib.  相似文献   
120.
A 1.6 kb gene encoding a cholesterol oxidase (choR) from a local isolate, Rhodococcus sp. PTCC 1633 was cloned into pET23a and the highly expressed recombinant enzyme was purified from the cell lysate of IPTG-induced Escherichia coli BL21(DE3)pLysS with one-step absorption on cholesterol. The purified protein had a molecular mass of 55 kDa, isoelectric point at about pH 9.0 and absorption peaks at 280, 380 and 460 nm, indicating that the enzyme is a flavoprotein. The optimum pH and temperature for the recombinant enzyme were 7.0 and 50°C, respectively. Steady-state kinetic revealed that the cholesterol oxidase had a K m of 32 μM. This study is the first report concerning expression and one-step purification of a gene encoding cholesterol oxidase from Rhodococcus spp. This study revealed that this enzyme is a type II cholesterol oxidase.  相似文献   
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