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51.
Russian Journal of Bioorganic Chemistry - A quantum chemical study was done on two compounds of proquazone and proquazone type calcilytics (6-methoxy-1-(propan-2-yl)-4-[4-(propan-2-yl)phenyl]-1,2...  相似文献   
52.
The Asian citrus psyllid (ACP, Diaphorina citri, Hemiptera: Liviidae), is the principal vector of the phloem-limited bacteria strongly associated with huanglongbing (HLB), the world’s most serious disease of citrus. Host plant resistance may provide an environmentally safe and sustainable method of controlling ACP and/or HLB. Two xCitroncirus accessions (hybrids of Poncirus trifoliata and Citrus spp.), that are relatively resistant (UN-3881) or relatively susceptible (Troyer-1459) to ACP adults with regard to adult longevity, were compared in relation to ACP feeding behavior and some structural features of the leaf midrib. The settling (putative feeding/probing) sites of ACP adults on various parts of the leaf were not influenced primarily by plant accession. However, fewer ACP stylet sheaths were found in the midrib and fewer stylet sheath termini reached the vascular bundle (phloem and/or xylem) in UN-3881 compared to Troyer-1459 plants. Furthermore, in midribs of UN-3881 leaves the fibrous ring (sclerenchyma) around the phloem was significantly wider (thicker) compared to that in midribs of Troyer-1459 leaves. Our data indicate that feeding and/or probing by ACP adults into the vascular bundle is less frequent in the more resistant (UN-3881) than in the more susceptible (Troyer-1459) accessions. Our results also suggest that the thickness of the fibrous ring may be a barrier to stylet penetration into the vascular bundle, which is important for successful ACP feeding on the phloem and for transmitting HLB-associated bacteria. These results may help in the development of citrus plants resistant to ACP, which in turn could halt or slow the spread of the HLB-associated bacteria by this vector.  相似文献   
53.
Despite the appealing hypothesis that carotenoid-based colouration signals oxidative status, evidence supporting the antioxidant function of these pigments is scarce. Recent studies have shown that lutein, the most common carotenoid used by birds, can enhance the expression of non-visual traits, such as birdsong. Nevertheless, the underlying physiological mechanisms remain unclear. In this study we hypothesized that male European starlings (Sturnus vulgaris) fed extra lutein increase their song rate as a consequence of an improved oxidative status. Although birdsong may be especially sensitive to the redox status, this has, to the best of our knowledge, never been tested. Together with the determination of circulating oxidative damage (ROMs, reactive oxygen metabolites), we quantified uric acid, albumin, total proteins, cholesterol, and testosterone, which are physiological parameters potentially sensitive to oxidation and/or related to both carotenoid functions and birdsong expression. We found that the birds fed extra lutein sang more frequently than control birds and showed an increase of albumin and cholesterol together with a decrease of oxidative damage. Moreover, we could show that song rate was associated with high levels of albumin and cholesterol and low levels of oxidative damage, independently from testosterone levels. Our study shows for the first time that song rate honestly signals the oxidative status of males and that dietary lutein is associated with the circulation of albumin and cholesterol in birds, providing a novel insight to the theoretical framework related to the honest signalling of carotenoid-based traits.  相似文献   
54.

Introduction

Endometrial cancer (EC) is associated with metabolic disturbances including obesity, diabetes and metabolic syndrome. Identifying metabolite biomarkers for EC detection has a crucial role in reducing morbidity and mortality.

Objective

To determine whether metabolomic based biomarkers can detect EC overall and early-stage EC.

Methods

We performed NMR and mass spectrometry based metabolomic analyses of serum in EC cases versus controls. A total of 46 early-stage (FIGO stages I–II) and 10 late-stage (FIGO stages III–IV) EC cases constituted the study group. A total of 60 unaffected control samples were used. Patients and controls were divided randomly into a discovery group (n?=?69) and an independent validation group (n?=?47). Predictive algorithms based on biomarkers and demographic characteristics were generated using logistic regression analysis.

Results

A total of 181 metabolites were evaluated. Extensive changes in metabolite levels were noted in the EC versus the control group. The combination of C14:2, phosphatidylcholine with acyl-alkyl residue sum C38:1 (PCae C38:1) and 3-hydroxybutyric acid had an area under the receiver operating characteristics curve (AUC) (95% CI)?=?0.826 (0.706–0.946) and a sensitivity?=?82.6%, and specificity?=?70.8% for EC overall. For early EC prediction: BMI, C14:2 and PC ae C40:1 had an AUC (95% CI)?=?0.819 (0.689–0.95) and a sensitivity?=?72.2% and specificity?=?79.2% in the validation group.

Conclusions

EC is characterized by significant perturbations in important cellular metabolites. Metabolites accurately detected early-stage EC cases and EC overall which could lead to the development of non-invasive biomarkers for earlier detection of EC and for monitoring disease recurrence.
  相似文献   
55.
Journal of Plant Growth Regulation - Plants face different types of biotic and abiotic stresses during their life span. Heavy metal (HM) stress is considered as one of the most challenging and...  相似文献   
56.
Whether cell-free human immunodeficiency virus type 1 (HIV-1) can productively infect placental trophoblasts (which in turn could transmit the virus into the fetal circulation) is controversial but essential to know for the evaluation of alternative routes (such as cell-mediated infection or trophoblast damage). We have addressed infection factors such as cell purity, source, culture methods, and activation states as well as virus variant and detection methods to conclusively determine the outcome of trophoblast challenge by free virus. Pure (> 99.98%) populations of trophoblasts from 11 different placentas were challenged at a multiplicity of infection (MOI) as high as 6 with five different HIV-1 variants, three of which are non-syncytium-forming, macrophage-tropic isolates from infected infants, with and without coinfection with cytomegalovirus; these preparations were monitored for productive infection for up to 3 weeks after challenge by five different criteria, the most sensitive of which were cocultivation with target cells that can detect virus at an MOI of 10(-7) and HIV DNA PCR that detects 30 virus copies per 10(5) cells. Infection was never detected. However, molecularly cloned T-cell (pNL4-3)- and macrophage (pNLAD8)-tropic provirus plasmids, when transfected into primary trophoblasts, yielded productive infections, indicating that trophoblasts do not suppress late-stage virus replication and assembly. Because of the purity of the trophoblast preparations, the extended length of the infection culture period, the number of trophoblast preparations and virus types examined, the sensitivity of the bioassays and molecular detection assays, and the observations that trophoblasts can support virus replication from provirus, the results of this study strongly argue that free virus cannot infect primary villous trophoblasts.  相似文献   
57.
Apis mellifera syriaca exhibits a high degree of tolerance to pests and pathogens including varroa mites. This native honey bee subspecies of Jordan expresses behavioral adaptations to high temperature and dry seasons typical of the region. However, persistent honey bee imports of commercial breeder lines are endangering local honey bee population. This study reports the use of next‐generation sequencing (NGS) technology to study the A. m. syriaca genome and to identify genetic factors possibly contributing toward mite resistance and other favorable traits. We obtained a total of 46.2 million raw reads by applying the NGS to sequence A. m. syriaca and used extensive bioinformatics approach to identify several candidate genes for Varroa mite resistance, behavioral and immune responses characteristic for these bees. As a part of characterizing the functional regulation of molecular genetic pathway, we have mapped the pathway genes potentially involved using information from Drosophila melanogaster and present possible functional changes implicated in responses to Varroa destructor mite infestation toward this. We performed in‐depth functional annotation methods to identify ~600 candidates that are relevant, genes involved in pathways such as microbial recognition and phagocytosis, peptidoglycan recognition protein family, Gram negative binding protein family, phagocytosis receptors, serpins, Toll signaling pathway, Imd pathway, Tnf, JAK‐STAT and MAPK pathway, heamatopioesis and cellular response pathways, antiviral, RNAi pathway, stress factors, etc. were selected. Finally, we have cataloged function‐specific polymorphisms between A. mellifera and A. m. syriaca that could give better understanding of varroa mite resistance mechanisms and assist in breeding. We have identified immune related embryonic development (Cactus, Relish, dorsal, Ank2, baz), Varroa hygiene (NorpA2, Zasp, LanA, gasp, impl3) and Varroa resistance (Pug, pcmt, elk, elf3‐s10, Dscam2, Dhc64C, gro, futsch) functional variations genes between A. mellifera and A. m. syriaca that could be used to develop an effective molecular tool for bee conservation and breeding programs to improve locally adapted strains such as syriaca and utilize their advantageous traits for the benefit of apiculture industry.  相似文献   
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