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21.
The common pistachio psylla, Agonoscena pistaciae (Hemiptera: Aphalaridae) is one of the most detrimental pests to pistachio trees. Nowadays various pesticides are used to control the common pistachio psylla, but extensive pesticide spraying against this pest over a period of several years has overpowered its natural enemies. The plant’s byproducts come as an alternative ecologically more compatible in substitution to the synthetic insecticides. This work aims to evaluate the insecticidal potential of herbal extracts of fruit peels of Citrus sinensis and Citrus reticulata, seeds of C. sinensis and Rubia tinctorum, and leaves of Lawsonia inermis against common pistachio psylla. Five concentration 40, 47, 56, 67 and 80 µl/ml, of these plant extracts were sprayed on the fifth instar nymphs of common pistachio psylla by Potter Spray Tower under laboratory conditions (26?±?2?°C, 60–70% RH and a photoperiod of 16L: 8D h). Results showed significant differences among the treatments of the plant extracts and between the concentrations. The LC50 values of C. sinensis peels, C. reticulata peels, C. sinensis seeds, R. tinctorum seeds and L. inermis leaves were 62.04, 38.84, 43.60, 59.01 and 33.99 µl/ml, respectively. Also, all extracts showed the greatest mortality effect in 80 µl/ml concentration. According to these results, these plant extracts may use as herbal pesticides chemical control programme of common pistachio psylla.  相似文献   
22.
Acute respiratory distress syndrome (ARDS) is the most common cause of death in COVID-19 patients. The cytokine storm is the main driver of the severity and magnitude of ARDS. Placenta-derived decidua stromal cells (DSCs) have a stronger immunosuppressive effect than other sources of mesenchymal stromal cells. Safety and efficacy study included 10 patients with a median age of 50 (range 14–68) years with COVID-19-induced ARDS. DSCs were administered 1–2 times at a dose of 1 × 106/kg. End points were safety and efficacy by survival, oxygenation and effects on levels of cytokines. Oxygenation levels increased from a median of 80.5% (range 69–88) to 95% (range 78–99) (p = 0.012), and pulmonary infiltrates disappeared in all patients. Levels of IL-6 decreased from a median of 69.3 (range 35.0–253.4) to 11 (range 4.0–38.3) pg/ml (p = 0.018), and CRP decreased from 69 (range 5–169) to 6 (range 2–31) mg/ml (p = 0.028). Two patients died, one of a myocardial infarction and the other of multiple organ failure, diagnosed before the DSC therapy. The other patients recovered and left the intensive care unit (ICU) within a median of 6 (range 3–12) days. DSC therapy is safe and capable of improving oxygenation, decreasing inflammatory cytokine level and clearing pulmonary infiltrates in patients with COVID-19.  相似文献   
23.
Salicyl alcohol oxidase is an extracellular enzyme that occurs in glandular reservoirs of chrysomelid leaf beetle larvae and catalyzes the formation of salicylaldehyde, a volatile deterrent used by the larvae against predators. Salicyl alcohol is the hydrolysis product of salicin, a plant-derived precursor taken up by the beetle larvae from the leaves of willow and poplar trees. The cDNA encoding salicyl alcohol oxidase from two related species Chrysomela tremulae and Chrysomela populi has been identified, cloned, and expressed in an active form in Escherichia coli. The open reading frame of 623 amino acids begins in both enzymes with an N-terminal signal peptide of 21 amino acids. Sequence comparison has revealed that salicyl alcohol oxidase belongs to the family of glucose-methanol-choline oxidoreductase-like sequences with mostly unknown function. Enzymes of this family share similar overall structure with an essentially identical FAD-binding site but possess different catalytic activities. The data suggest that salicyl alcohol oxidase, essential for the activation of the plant-derived precursor salicin, was originally recruited from an oxidase involved in the autogenous biosynthesis of iridoid monoterpenes and found in related chrysomelid leaf beetle species.  相似文献   
24.
ObjectivesTyphoid fever is caused by Salmonella enterica serovar Typhi. OmpC, OmpF and OmpA, the three major outer membrane proteins (OMPs), could serve as vaccine candidates.MethodsThe porins antigenicity was predicted in silico. The OMP genes were amplified, cloned and expressed. Sero-reactivities of the recombinant proteins purified by denaturing method were assayed by ELISA. BALB/c mice were immunized with the recombinant porins followed by bacterial challenge.ResultsBacterial challenge of the animal model brought about antibody triggering efficacy of the antigen in OmpF > OmpC > OmpA order. Experimental findings validated the in silico results. None of the antigens had synergic or antagonistic effects on each other from immune system induction points of view. Despite their high immunogenicity, none of the antigens was protective. However, administration of two or three antigens simultaneously resulted in retardation of lethal effect. Porins, in addition to their specific functions, share common functions. Hence, they can compensate for each other's functions.ConclusionsThe produced antibodies could not eliminate the pathogenicity by blockade of one or some of the antigens. Porin antigens are not suitable vaccine candidates alone or in denatured forms. Native forms of the antigens maybe studied for protective immunogenicity.  相似文献   
25.
Sexual development in the filamentous model ascomycete Trichoderma reesei (syn. Hypocrea jecorina) was described only a few years ago. In this study, we show a novel role for VELVET in fungi, which links light response, development and secondary metabolism. Vel1 is required for mating in darkness, normal growth and conidiation. In light, vel1 was dispensable for male fertility but essential for female fertility in both mating types. VEL1 impacted regulation of the pheromone system (hpr1, hpr2, hpp1, ppg1) in a mating type‐dependent manner and depending on the mating partner of a given strain. These partner effects only occurred for hpp1 and hpr2, the pheromone precursor and receptor genes associated with the MAT1‐2 mating type and for the mating type gene mat1‐2‐1. Analysis of secondary metabolite patterns secreted by wild type and mutants under asexual and sexual conditions revealed that even in the wild type, the patterns change upon encounter of a mating partner, with again distinct differences for wild type and vel1 mutants. Hence, T. reesei applies a language of pheromones and secondary metabolites to communicate with mating partners and that this communication is at least in part mediated by VEL1.  相似文献   
26.
A new Nipergasilus species is described from the gills of the grey mullet Valamugil cunnesius from several localities in India and Pakistan. The new species is closely related to Nipergasilus bora (Yamaguti, 1939) which is also recorded here on three species of grey mullet. The genus Nipergasilus is redefined in order to accommodate the second species.  相似文献   
27.
A novel candidate metastasis modifier, ribosomal RNA processing 1 homolog B (Rrp1b), was identified through two independent approaches. First, yeast two-hybrid, immunoprecipitation, and functional assays demonstrated a physical and functional interaction between Rrp1b and the previous identified metastasis modifier Sipa1. In parallel, using mouse and human metastasis gene expression data it was observed that extracellular matrix (ECM) genes are common components of metastasis predictive signatures, suggesting that ECM genes are either important markers or causal factors in metastasis. To investigate the relationship between ECM genes and poor prognosis in breast cancer, expression quantitative trait locus analysis of polyoma middle-T transgene-induced mammary tumor was performed. ECM gene expression was found to be consistently associated with Rrp1b expression. In vitro expression of Rrp1b significantly altered ECM gene expression, tumor growth, and dissemination in metastasis assays. Furthermore, a gene signature induced by ectopic expression of Rrp1b in tumor cells predicted survival in a human breast cancer gene expression dataset. Finally, constitutional polymorphism within RRP1B was found to be significantly associated with tumor progression in two independent breast cancer cohorts. These data suggest that RRP1B may be a novel susceptibility gene for breast cancer progression and metastasis.  相似文献   
28.
We explored how often journal articles reporting HIV research sponsored by a developed country, but conducted in a developing country, mention research ethics committee (REC) approval from both countries, and what factors are involved. Of all such 2007 articles on Medline conducted in one of four developing countries (N = 154), only 52% mentioned such dual approval. Mention of dual vs. single approval was more likely among articles with ≥ 50% sponsor country authors, and the United States as the sponsor country. Also, dual approval was more likely among articles that mentioned informed consent and funding, had ≥ 50% sponsor country authors, were biomedical (vs. psychosocial), and appeared in journals adopting International Committee Medical Journal Editors (ICMJE) guidelines. Dual approval was thus obtained in only half of the articles and was associated with ethical and logistic issues, indicating the need for clearer and more universally accepted guidelines.  相似文献   
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30.
A twelve-month survey for mosquito predators was conducted in Townsville, Queensland, Australia, which is located in the arid tropics. The survey revealed the presence of five predaceous insects but only Anisops sp. (backswimmers) and Diplonychus sp. were common. Predatorial capacity and factors influencing this capacity were then assessed for adult Anisops sp. and adult and nymph stages of Diplonychus sp. against Culex annulirostris mosquito immatures under laboratory conditions. Predatorial capacity bioassays showed that adult Diplonychus sp. preyed upon both larval and pupal stages of Cx. annulirostris quite successfully. Nymphs of Diplonychus sp. proved to be more successful with smaller prey immatures, and Anisops sp adults did not prey successfully on any prey pupae. Increasing the foraging area and introducing aquatic vegetation significantly reduced the predatorial capacity of Diplonychus sp. nymphs, while only vegetation and not foraging area had a significant effect on adult Diplonychus sp. predation capacity. Overall, adult Diplonychus sp. proved to be a more efficient predator than Anisops sp., and field trials are now recommended to further assess the potential of Diplonychus sp. as a biocontrol agent.  相似文献   
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