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91.
Background and AimsOrnamental flowering plant species are often used in managed greenspaces to attract and support pollinator populations. In natural systems, selection by pollinators is hypothesized to result in convergent multimodal floral phenotypes that are more attractive to specific pollinator taxa. In contrast, ornamental cultivars are bred via artificial selection by humans, and exhibit diverse and distinct phenotypes. Despite their prevalence in managed habitats, the influence of cultivar phenotypic variation on plant attractiveness to pollinator taxa is not well resolved.MethodsWe used a combination of field and behavioural assays to evaluate how variation in floral visual, chemical and nutritional traits impacted overall attractiveness and visitation by pollinator taxonomic groups and bee species to 25 cultivars of five herbaceous perennial ornamental plant genera.Key resultsDespite significant phenotypic variation, cultivars tended to attract a broad range of pollinator species. Nonetheless, at the level of insect order (bee, fly, butterfly, beetle), attraction was generally modulated by traits consistent with the pollination syndrome hypothesis. At the level of bee species, the relative influence of traits on visitation varied across plant genera, with some floral phenotypes leading to a broadening of the visitor community, and others leading to exclusion of visitation by certain bee species.ConclusionsOur results demonstrate how pollinator choice is mediated by complex multimodal floral signals. Importantly, the traits that had the greatest and most consistent effect on regulating pollinator attraction were those that are commonly selected for in cultivar development. Though variation among cultivars in floral traits may limit the pollinator community by excluding certain species, it may also encourage interactions with generalist taxa to support pollinator diversity in managed landscapes.  相似文献   
92.
BackgroundAmino acids have an important role in metabolism and may affect COVID-19-related outcomes. In our study, the amino acid serum level of hospitalized COVID19 patients was evaluated to determine a new treatment strategy.MethodsThe amino acid profile covering 43 amino acids in 68 subjects, comprising 30 (14 men and 16 women) controls and 38 (16 men and 22 women) COVID-19 patients, were examined. The amino acid profiles of the participants were screened by LC-MS/MS.ResultsCompared with the control group, serum levels of 27 amino acids increased in the patient group. Alpha-aminopimelic acid, sarcosine, and hydroxyproline amino acids were considerably higher in the control group than in the patient group (p<0.0001). There was no notable difference among control group and the case group for 13 amino acids (p≥0.05). A significant positive correlation was seen among the control and the patient groups in the mean amino acid values (r=0.937; p<0.0001).ConclusionsThese results postulated a clear picture on the serum levels of amino acid in the COVID-19 patients. Serum amino acids measured in hospitalized COVID-19 patients can explain the patient''s metabolic status during the disease.  相似文献   
93.
BackgroundAcross the world, 25-hydroxyvitamin D (25-OHD) deficiency is a major health problem associated with many chronic diseases in the geriatric population. Prior to this study, there were no data regarding 25-OHD levels among individuals over the age of 65 in Turkey. The aim of this study was to assess 25-OHD levels and seasonal variations in these values among people over the age of 65 in Turkey.MethodsThis study included vitamin D measurements taken in 2016, 2017, and 2018 from the Turkish population over the age of 65. The age, gender, and seasonal average data of the study population were defined. The study data were obtained from the database of the Ministry of Health, and a Kolmogorov-Smirnov test was used to assess the distribution of the data. Medians and interquartile ranges (IQRs) were calculated for all categories, as the data were nonparametric.ResultsThe number of vitamin D measurements taken from the geriatric individuals included in this study was 305,329 for 2016, 576,452 for 2017, and 752,837 for 2018. The medians and IQRs of the 25-OHD levels in this population were 16 μg/L (IQR 7.45-24.55 μg/L) for 2016, 16.1 μg/L (IQR 7.8-24.4 μg/L) for 2017, and 16.4 μg/L (IQR 8.95-23.85 μg/L) for 2018.ConclusionsWhile the 25-OHD levels of older men tended to increase during the period of seasonal sunlight in Turkey, this variability was observed in elderly women. This suggests that older women tend to live more sedentary lives and have insufficient sun exposure. Overall, the median 25-OHD levels of individuals over the age of 65 tended to decrease each year.  相似文献   
94.
Different growth factors can regulate stem cell differentiation. We used keratinocyte growth factor (KGF) to direct adipose‐derived stem cells (ASCs) differentiation into keratinocytes. To enhance KGF bioavailability, we targeted KGF for collagen by fusing it to collagen‐binding domain from Vibrio mimicus metalloprotease (vibrioCBD‐KGF). KGF and vibrioCBD‐KGF were expressed in Escherichia coli and purified to homogeneity. Both proteins displayed comparable activities in stimulating proliferation of HEK‐293 and MCF‐7 cells. vibrioCBD‐KGF demonstrated enhanced collagen‐binding affinity in immunofluorescence and ELISA. KGF and vibrioCBD‐KGF at different concentrations (2, 10, and 20 ng/ml) were applied for 21 days on ASCs cultured on collagen‐coated plates. Keratinocyte differentiation was assessed based on morphological changes, the expression of keratinocyte markers (Keratin‐10 and Involucrin), and stem cell markers (Collagen‐I and Vimentin) by real‐time PCR or immunofluorescence. Our results indicated that the expression of keratinocyte markers was substantially increased at all concentrations of vibrioCBD‐KGF, while it was observed for KGF only at 20 ng/ml. Immunofluorescence staining approved this finding. Moreover, down‐regulation of Collagen‐I, an indicator of differentiation commitment, was more significant in samples treated with vibrioCBD‐KGF. The present study showed that vibrioCBD‐KGF is more potent in inducing the ASCs differentiation into keratinocytes compared to KGF. Our results have important implications for effective skin regeneration using collagen‐based biomaterials.  相似文献   
95.
Background:Bronchial asthma has a complicated genetic history. Changes in gene expression may be caused by gene polymorphism, cytokines play a central role. IL-13 is an interleukin that has been shown to play a role in the disease''s immunopathogenesis. The current study investigated the relationship between rs20541 of the IL-13 gene and Bronchial asthma in Iraqi patients.Methods:Seventy-five patient and fifty healthy individuals as a control. The DNA was extracted from blood samples. Detection of genotype IL-13SNP (rs20541) were achieved by RFLP-PCR.Results:indicated a highly significant the levels of the IgE, and IL-13 in the patients compared to control at (p value≤ 0.01), (456.45±290.106 vs. 30.08±24.414), (59.5980±20.93750 vs.6.7034±4.10547) pg/ml respectively. Result shows no significant differences in the frequency distributions of IL-13 SNP (rs20541) for all genotypes in cases and controls. A protective role of asthma, (OR: 0.62; CI.95%: 0.23 - 1.6) and (OR 0.89; CI.95%:0.42 - 1.89) were observed for wild type homozygous and heterozygous genotype respectively. Whereas the AA genotype (42.7%) in cases and (34.0%) in control, that (OR:1.44; CI.95%:( 0.66 - 3.07) mutant homozygous were risk factors of asthma among individuals. The genotypes of IL-13 rs20541 (GG, AG, AA) among patients and controls were significantly correlated with IgE and IL-13 results at (p≤ 0.05).Conclusion:AA genotype in case and control mutant homozygous were risk factors of asthma among individuals. It’s possible that this has a predisposing impact on the development of asthma.Key Words: Bronchial Asthma, RFLP, IL-13, SNP  相似文献   
96.
We have observed previously that the reactions catalyzed by hypoxanthine/guanine phosphoribosyltransferase (HGPRTase) are activated by Mg(II), Mn(II), and Co(II), and we have defined the mechanism by which these activations proceed [Biochemistry 22, 3419-3424 (1983)]. A more extensive survey of the kinds of metal ions that will activate the HGPRTase catalysis now has been completed through the use of an HPLC assay procedure. Although Fe(II) and Ca(II) are unable to activate this reaction, a significant activation was achieved with the addition of spectroscopically pure Zn(II) to the assay solution. In addition some IMP synthesis resulted from the addition of Ni(II) to the assay mixture. Both the Zn(II) and Ni(II) kinetic effects on HGPRTase over a limited metal ion concentration range have been analyzed through the use of curve-fitting exercises. These results, in addition to the similar pH profiles for the activations by Mg(II), Mn(II), Co(II), and Zn(II), suggest that all of these metal ions activate the HGPRTase-catalyzed synthesis of IMP by way of the same mechanism [model II as defined by London and Steck, Biochemistry 8, 1767-1779 (1969)], during which two divalent ions bind to the HGPRTase active site per molecule of PRibPP.  相似文献   
97.
98.
Between 2018 and 2020, 696 fish belonging to two species of sharks from the Family Triakidae (Mustelus mustelus and M. punctulatus) were collected from the coasts of Tunisia and inspected for parasites. Six copepod taxa (Perissopus dentatus Steenstrup & Lütken, 1861, Eudactylinella alba Wilson, 1932, Kroyeria lineata Van Beneden, 1853, Nesippus orientalis Heller, 1865 and Lernaeopoda galei Krøyer, 1837, Kroyeria sp.), four isopod species (Anilocra physodes (Linnaeus, 1758), Emetha audouini (H. Milne Edwards, 1840), Ceratothoa parallela (Otto, 1828) and Ceratothoa oestroides (Risso, 1816)) and two monogenean species (Erpocotyle sp1. And Erpocotyle sp2) were collected. A large number of global host records was reported, including the occurrence of E. audouini on M. mustelus and of Erpocotyle sp.2 on M. punctulatus. The study of the diversity of parasites per host species revealed that M. mustelus had a higher parasitic richness compared to M. punctulatus. In this study, it was provided for the first records on ectoparasites on Triakidae sharks from Tunisian coasts and their infection indices.  相似文献   
99.
The enhanced understanding of chloroplast genomics would facilitate various biotechnology applications; however, the chloroplast (cp) genome / plastome characteristics of plants like Fagonia indica Burm.f. (family Zygophyllaceae), which have the capability to grow in extremely hot sand desert, have been rarely understood. The de novo genome sequence of F. indica using the Illumina high-throughput sequencing technology determined 128,379 bp long cp genome, encode 115 unique coding genes. The present study added the evidence of the loss of a copy of the IR in the cp genome of the taxa capable to grow in the hot sand desert. The maximum likelihood analysis revealed two distinct sub-clades i.e. Krameriaceae and Zygophyllaceae of the order Zygophyllales, nested within fabids.  相似文献   
100.
Bio-fertilization is a sustainable agricultural practice that includes using bio-fertilizers to increase soil nutrient content resulting in higher productivity. Soil micro-flora has been exposed to improve soil fertility and increase biomass productivity and identified as a correct environmentally friendly bio-based fertilizer for pollution-free agricultural applies. The majority of cyanobacteria can fix nitrogen from the atmosphere and several species including Anabaena sp., Nostoc sp., and Oscillatoria angustissima is known to be effective cyanobacterial based bio fertilizers. Acutodesmus dimorphus, Spirulina platensis Chlorella vulgaris, Scenedesmus dimorphus, Anabaena azolla, and Nostoc sp. are some of the green microalgae and cyanobacteria species that have been successfully used as bio fertilizers to boost crop growth. Also, Chlorella vulgaris is one of the most commonly used microalgae in bio fertilizer studies. The addition of seaweed species that are Sargassum sp. and Gracilaria verrucosa leads to chemical changes as a soil fertility indicator on clay and sandy soils, and the addition of seaweed conditioner to soil can improve its organic content, return pH to normal, and reduce C/N ratio in both sandy and clay soil. This review provides an effective approach to increase soil fertility via environmentally friendly bio-based fertilizer using micro and macro algae. Instead of the usage of inorganic and organic fertilizers that have polluted impacts to soil as aggregation of heavy metals, in addition to there their human carcinogenic effects.  相似文献   
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