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1.
Abstract

Red flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) is a prominent pest of stored products particularly cereal flour. Since resistance of this pest to common chemical insecticides is well documented, we were examined the synergistic/antagonistic interaction between Satureja hortensis L., Trachyspermum ammi L., Ziziphora tenuior L., Cuminum cyminum L. and Foeniculum vulgare Miller essential oils, ethanolic extracts and powders with Diatomaceous earth (DE) against T. castaneum adults under laboratory conditions at 27 ± 1 °C, 65 ± 5% RH and continuous darkness. We assayed repellency of ethanolic extracts and essential oils of mentioned plants on the pest. Results showed that DE had high toxicity to the pest. Plant essential oils and ethanolic extracts (except ziziphora) synergized the performance of DE. Nevertheless, plant powders elicited antagonistic effects (except ziziphora that exhibited synergistic effect). The most repellent EO and extract was cumin which exhibited mean repellency value on adult insect equivalent to 92.58 and 51.47%, respectively.  相似文献   
2.
In recent years, grapevine trunk diseases have gained growing attentions due to worldwide incidence of the disease. In a survey on fungal agents associated with grapevine trunk diseases in northern Iran, wood samples were collected from grapevines having the symptoms of declination. Isolation was made using routine plant pathology methods. A coelomycetous fungus with appendage-bearing conidia was recovered from symptomatic tissues. Based on morphological and cultural characteristics, the causal agent of the disease was identified as Truncatella angustata. The identity of the species was further confirmed by sequence data of internal transcribed spacer-rDNA region. A phylogeny inferred using sequence data obtained in this study, together with the sequences from GenBank, clustered our isolates together with T. angustata known from other host plant species. Pathogenicity tests performed on detached shoots of grapevines led to the same symptoms as observed in field conditions. This is first study on the pathogenicity of T. angustata on grapevine in Iran and first report on the occurrence of T. angustata on grapevine in Iran.  相似文献   
3.
A long‐standing goal for biologists and social scientists is to understand the factors that lead to the evolution and maintenance of co‐operative behaviour between conspecifics. To that end, the fruit fly, Drosophila melanogaster, is becoming an increasingly popular model species to study sociality; however, most of the research to date has focused on adult behaviours. In this study, we set out to examine group‐feeding behaviour by larvae and to determine whether the degree of relatedness between individuals mediates the expression co‐operation. In a series of assays, we manipulated the average degree of relatedness in groups of third‐instar larvae that were faced with resource scarcity, and measured the size, frequency and composition of feeding clusters, as well as the fitness benefits associated with co‐operation. Our results suggest that larval D. melanogaster are capable of kin recognition (something that has not been previously described in this species), as clusters were more numerous, larger and involved more larvae, when more closely related kin were present in the social environment. These findings are discussed in the context of the correlated fitness‐associated benefits of co‐operation, the potential mechanisms by which individuals may recognize kin, and how that kinship may play an important role in facilitating the manifestation of this co‐operative behaviour.  相似文献   
4.
The Wnt/β-catenin pathway is one of the most common pathways dysregulated in breast cancer, and may, therefore, be a potential-therapeutic target. We have investigated the effects of PNU-74654 in breast cancer, as a Wnt/β-catenin inhibitor, either alone or in combination with fluorouracil (5-FU). PNU-74654 suppressed cell growth at an IC 50 of 122 ± 0.4 μmol/L and synergistically enhanced the antiproliferative activity of gemcitabine by modulating the Wnt pathway. Using a 3D cell culture model, we found that the PNU-74654 caused tumor shrinkage. It reduced the migration of MCF-7 cells (by an 18% reduction in invasive behavior) after the treatment with PNU-74654 through perturbation of E-cadherin and MMP3/9. PNU-74654/5-FU combination enhanced the percentages of cells in S-phase and significantly increased apoptosis. Moreover, our data showed that this agent was able to inhibit the growth of tumor in a xenograft model, although this effect was more pronounced in the animals treated with PNU-74654 plus 5-FU. These data show the ability of PNU-74654 to specifically target Wnt pathway, interfere with cell proliferation, induce-apoptosis, reduce-migration, and synergistically interact with 5-FU, supporting further studies on this novel therapeutic-approach for breast cancer.  相似文献   
5.
An experiment was conducted to study seasonal variations of thyroidal activity, serum testosterone concentration and seminal characteristics of two breeds of Iranian fat-tailed sheep. Eight 3 to 4-year-old rams of Ghezel and Mehraban breeds (4 rams/breed) were randomly selected from a flock of fertile rams. Semen was collected by using an artificial vagina, and blood samples were obtained via jugular vein. Seminal characteristics, scrotal length, width, and circumference, and blood parameters were measured at 3-week intervals. Time of the year significantly (P < 0.05) affected the volume of semen, sperm concentration, percent live sperm, percent normal sperm, total sperm number, seminal pH, seminal lactate dehydrogenase (LDH) concentration, scrotal circumference, scrotal width, and serum levels of testosterone, cholesterol, triiodothyronine (T(3)), tetraiodothyronine (T(4)), free T(4) index (FT(4)I), and TSH. Scrotal length was not affected by the time of sampling (P > 0.05). The effect of breed on the serum concentrations of hormones and cholesterol was not significant. Volume of semen, percent normal sperm, and total number of normal sperm were significantly (P < 0.05) higher in Mehraban but scrotal circumference, scrotal width and scrotal length were greater in Ghezel rams. Breedxtime interaction effect was significant for T(4), FT(4)I, sperm concentration, and total sperm number. The largest values for TSH, T(4), FT(4)I, testosterone, total sperm number, percent normal sperm, percent live sperm, sperm concentration, volume of semen and scrotal circumference were found from early summer to winter and the lowest values were recorded at the end of spring and in early summer. In both breeds, high and negative correlations (r = -0.7 to -0.8) were found between LDH levels in semen and percent live sperm, percent normal sperm and total sperm number (P < 0.01). It is unlikely that such variations in seminal quality would affect the fertility under natural mating.  相似文献   
6.
Behaviors are often influenced by both ecology and genetics. Perez et al. tested whether display patterns and the ecology of different species of fiddler crabs influence synchronous waving and whether this a phylogenetic phenomenon. They found that there was no phylogenetic signal in wave display synchronicity, and suggested that signal structure, microhabitat complexity, and different mating systems might instead be the cause. These results support the non-phylogenetic nature of synchronicity that can be observed across animal taxa.  相似文献   
7.
IntroductionThe relationship between demographic and biochemical characteristics, including several established coronary risk factors, and serum copper and zinc was assessed in a large Iranian population sample.Materials and methodsA group of 2233 individuals, 15–65 years of age [1106 (49.5%) males and 1127 (50.5%) females] was recruited from residents of the Greater Khorasan province in northeast of Iran. Demographic data were collected using questionnaires. Coronary risk factors were determined using standard protocols, and trace elements were measured in serum using atomic absorption spectroscopy.ResultsDegree of glucose tolerance and smoking habit were not associated with serum zinc and copper levels. Serum copper levels were significantly higher in obese and hypertensive than in normal subjects (p<0.001). In the whole group and for the female subgroup, serum zinc (p<0.01) and copper (p<0.001) were both significantly lower in individuals with normal versus high levels of low-density lipoprotein cholesterol.A strong positive correlation was found between serum copper and body mass index (BMI) (r=0.85, p<0.001). Weaker positive associations were found between serum copper and calculated 10 years’ coronary risk (r=0.11, p<0.001). Serum zinc/copper ratio was strongly inversely associated with calculated 10 years’ coronary risk (r=?0.10, p<0.001). The partial Eta squared (PES) values for factors determining serum zinc were hypertension (0.007, p=0.01) and BMI (0.004, p=0.01); and for serum copper, they were gender (0.02, p=0.001), hypertension (0.004, p=0.009), and 10 years’ coronary risk for men (0.003, p=0.03) and women (0.002, p=0.07).ConclusionSignificant associations between serum trace element concentrations and several coronary risk factors, including calculated 10 years’ coronary risk scores, were found.  相似文献   
8.
9.
Polygonatum odoratum (Mill.) Druce (Angular Solomon's seal) is a well‐known ornamental plant and herbal drug, which is used in traditional medicine. Severe leaf spots were observed in wild Angular Solomon's seal plants in a public park in Trento, Italy. A combination of morphological and molecular characteristics, including sequence data of ITS‐rDNA, large subunit (LSU), beta tubulin (TUB) and glyceraldehyde 3‐phosphate dehydrogenase (GAPDH) led to identification of two species, namely Phoma odoratissimi and Colletotrichum dematium s. str., isolated from these leaf spots. Pathogenicity of the isolates was confirmed on wounded leaves of Po. odoratum; indeed, both species induced leaf spot symptoms on inoculated leaves within 10 days of inoculation. This is the first report of leaf spot disease caused by Ph. odoratissimi and C. dematium s. str. on Po. odoratum, which can be considered a new host for both the species examined in this study. In addition, isolation of Ph. odoratissimi represents a new record for the mycobiota of Italy.  相似文献   
10.
Hypospadias is among the most common congenital malformations in male neonates. It results from abnormal penile and urethral development, but is a multifactorial disorder that is highly heterogeneous, with several genetic and environmental determinants. Monogenic and chromosomal abnormalities are present in approximately 30% of cases, although the genetic factors contributing to hypospadias remain unknown in 70% of cases. While defects in androgen synthesis can lead to this malformation, mutational analyses have shown several genes, such as sonic hedgehog, fibroblast growth factors, bone morphogenetic proteins, homeobox genes, and the Wnt family, are involved in the normal development of male external genitalia. Mutations in the genes of penile development (e.g., HOX, FGF, Shh) and testicular determination (e.g., WT1, SRY), luteinizing hormone receptor, and androgen receptor have also been proposed to be implicated in hypospadias. Here we review the recent advances in this field and discuss the potential genes that could determine the risk of hypospadias.  相似文献   
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