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101.
In loquat (Eriobotrya japonica Lindl.), the comparison of fruiting trees and defruited trees carried out covering a range of developmental fruit stages reveals a significant reduction in flowering due to fruit from its early stage of development, being higher when it changes color and becomes senescent, which coincides with the floral bud inductive period. This effect occurred both at the tree and at the shoot level. Furthermore, although current shoots almost always develop into panicles, those from fruiting trees develop fewer flowers, suggesting that fruit also affects at the floral bud level. In our experiment, the gibberellin concentration at the floral bud inductive period was significantly higher in bark tissues (periderm, cortex and phloem tissues) of fruiting trees, compared with defruited trees that tend to flower more. The lower concentration of IAA in the bark tissues of defruited trees also contributes to increase their flowering intensity. On the contrary, the zeatin concentration was higher. Accordingly, at bud burst, the IAA/zeatin ratio, an indication of effect on flowering, was significantly higher for fruiting trees. Some disruption in the nitrate reduction process in fruiting tree was also observed. The process of floral bud induction and differentiation was not associated with either reducing or translocating and reserve carbohydrate concentration. Hence, loquat flower intensity depends on the time the fruit is maintained on the tree. The intensity is affected indirectly, by reducing the number of shoots, and directly, by reducing the number of flowers per panicle, and these effects are linked to endogenous plant hormone contents.  相似文献   
102.
DNA methylation changes contribute to bladder carcinogenesis. Trihalomethanes (THM), a class of disinfection by-products, are associated with increased urothelial bladder cancer (UBC) risk. THM exposure in animal models produces DNA hypomethylation. We evaluated the relationship of LINE-1 5-methylcytosine levels (LINE-1%5mC) as outcome of long-term THM exposure among controls and as an effect modifier in the association between THM exposure and UBC risk. We used a case-control study of UBC conducted in Spain. We obtained personal lifetime residential THM levels and measured LINE-1%5mC by pyrosequencing in granulocyte DNA from blood samples in 548 incident cases and 559 hospital controls. Two LINE-1%5mC clusters (above and below 64%) were identified through unsupervised hierarchical cluster analysis. The association between THM levels and LINE-1%5mC was evaluated with β regression analyses and logistic regression was used to estimate odds ratios (OR) adjusting for covariables. LINE-1%5mC change between percentiles 75th and 25th of THM levels was 1.8% (95% confidence interval (CI): 0.1, 3.4%) among controls. THM levels above vs. below the median (26 μg/L) were associated with increased UBC risk, OR = 1.86 (95% CI: 1.25, 2.75), overall and among subjects with low levels of LINE-1%5mC (n = 975), OR = 2.14 (95% CI: 1.39, 3.30), but not associated with UBC risk among subjects’ high levels of LINE-1%5mC (n = 162), interaction P = 0.03. Results suggest a positive association between LINE-1%5mC and THM levels among controls, and LINE-1%5mC status may modify the association between UBC risk and THM exposure. Because reverse causation and chance cannot be ruled out, confirmation studies are warranted.  相似文献   
103.
Treatment with the resistance priming inducer hexanoic acid (Hx) protects tomato plants from Botrytis cinerea by activating defence responses. To investigate the molecular mechanisms underlying hexanoic acid‐induced resistance (Hx‐IR), we compared the expression profiles of three different conditions: Botrytis‐infected plants (Inf), Hx‐treated plants (Hx) and Hx‐treated + infected plants (Hx+Inf). The microarray analysis at 24 h post‐inoculation showed that Hx and Hx+Inf plants exhibited the differential expression and priming of many Botrytis‐induced genes. Interestingly, we found that the activation by Hx of other genes was not altered by the fungus at this time point. These genes may be considered to be specific targets of the Hx priming effect and may help to elucidate its mechanisms of action. It is noteworthy that, in Hx and Hx+Inf plants, there was up‐regulation of proteinase inhibitor genes, DNA‐binding factors, enzymes involved in plant hormone signalling and synthesis, and, remarkably, the genes involved in oxidative stress. Given the relevance of the oxidative burst occurring in plant–pathogen interactions, the effect of Hx on this process was studied in depth. We showed by specific staining that reactive oxygen species (ROS) accumulation in Hx+Inf plants was reduced and more restricted around infection sites. In addition, these plants showed higher ratios of reduced to oxidized glutathione and ascorbate, and normal levels of antioxidant activities. The results obtained indicate that Hx protects tomato plants from B. cinerea by regulating and priming Botrytis‐specific and non‐specific genes, preventing the harmful effects of oxidative stress produced by infection.  相似文献   
104.

Background

Patients with chronic obstructive pulmonary disease (COPD) often suffer concomitant disorders that worsen significantly their health status and vital prognosis. The pathogenic mechanisms underlying COPD multimorbidities are not completely understood, thus the exploration of potential molecular and biological linkages between COPD and their associated diseases is of great interest.

Methods

We developed a novel, unbiased, integrative network medicine approach for the analysis of the diseasome, interactome, the biological pathways and tobacco smoke exposome, which has been applied to the study of 16 prevalent COPD multimorbidities identified by clinical experts.

Results

Our analyses indicate that all COPD multimorbidities studied here are related at the molecular and biological level, sharing genes, proteins and biological pathways. By inspecting the connections of COPD with their associated diseases in more detail, we identified known biological pathways involved in COPD, such as inflammation, endothelial dysfunction or apoptosis, serving as a proof of concept of the methodology. More interestingly, we found previously overlooked biological pathways that might contribute to explain COPD multimorbidities, such as hemostasis in COPD multimorbidities other than cardiovascular disorders, and cell cycle pathway in the association of COPD with depression. Moreover, we also observed similarities between COPD multimorbidities at the pathway level, suggesting common biological mechanisms for different COPD multimorbidities. Finally, chemicals contained in the tobacco smoke target an average of 69% of the identified proteins participating in COPD multimorbidities.

Conclusions

The network medicine approach presented here allowed the identification of plausible molecular links between COPD and comorbid diseases, and showed that many of them are targets of the tobacco exposome, proposing new areas of research for understanding the molecular underpinning of COPD multimorbidities.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-014-0111-4) contains supplementary material, which is available to authorized users.  相似文献   
105.
106.
Cattle ticks are distributed worldwide and affect animal health and livestock production. White tailed deer (WTD) sustain and spread cattle tick populations. The aim of this study was to model the efficacy of anti-tick vaccination of WTD to control tick infestations in the absence of cattle vaccination in a territory where both host species coexist and sustain cattle tick populations. Agent-based models that included land cover/landscape properties (patch size, distances to patches) and climatic conditions were built in a GIS environment to simulate WTD vaccine effectiveness under conditions where unvaccinated cattle shared the landscape. Published and validated information on tick life cycle was used to build models describing tick mortality and developmental rates. Data from simulations were applied to a large territory in northeastern Mexico where cattle ticks are endemic and WTD and cattle share substantial portions of the habitat. WTD movements were simulated together with tick population dynamics considering the actual landscape and climatic features. The size of the vegetation patches and the distance between patches were critical for the successful control of tick infestations after WTD vaccination. The presence of well-connected, large vegetation patches proved essential for tick control, since the tick could persist in areas of highly fragmented habitat. The continued application of one yearly vaccination on days 1-70 for three years reduced tick abundance/animal/patch by a factor of 40 and 60 for R. annulatus and R. microplus, respectively when compared to non-vaccinated controls. The study showed that vaccination of WTD alone during three consecutive years could result in the reduction of cattle tick populations in northeastern Mexico. Furthermore, the results of the simulations suggested the possibility of using vaccines to prevent the spread and thus the re-introduction of cattle ticks into tick-free areas.  相似文献   
107.
Thymic alterations in EphA4-deficient mice   总被引:2,自引:0,他引:2  
In the present work, we have demonstrated in vivo an altered maturation of the thymic epithelium that results in defective T cell development which increases with age, in the thymus of Eph A4-deficient mice. The deficient thymi are hypocellular and show decreased proportions of double-positive (CD4+CD8+) cells which reach minimal numbers in 4-wk-old thymi. The EphA4 (-/-) phenotype correlates with an early block of T cell precursor differentiation that results in accumulation of CD44-CD25+ triple-negative cells and, sometimes, of CD44+CD25- triple-negative thymocytes as well as with increased numbers of apoptotic cells and an important reduction in the numbers of cycling thymocytes. Various approaches support a key role of the thymic epithelial cells in the observed phenotype. Thymic cytoarchitecture undergoes profound changes earlier than those found in the thymocyte maturation. Thymic cortex is extremely reduced and consists of densely packed thymic epithelial cells. Presumably the lack of forward Eph A4 signaling in the Eph A4 -/- epithelial cells affects their development and finally results in altered T cell development.  相似文献   
108.
During mycobacterial infection, macroautophagy/autophagy, a process modulated by cytokines, is essential for mounting successful host responses. Autophagy collaborates with human immune responses against Mycobacterium tuberculosis (Mt) in association with specific IFNG secreted against the pathogen. However, IFNG alone is not sufficient to the complete bacterial eradication, and other cytokines might be required. Actually, induction of Th1 and Th17 immune responses are required for protection against Mt. Accordingly, we showed that IL17A and IFNG expression in lymphocytes from tuberculosis patients correlates with disease severity. Here we investigate the role of IFNG and IL17A during autophagy in monocytes infected with Mt H37Rv or the mutant MtΔRD1. Patients with active disease were classified as high responder (HR) or low responder (LR) according to their T cell responses against Mt. IL17A augmented autophagy in infected monocytes from HR patients through a mechanism that activated MAPK1/ERK2-MAPK3/ERK1 but, during infection of monocytes from LR patients, IL17A had no effect on the autophagic response. In contrast, addition of IFNG to infected monocytes, increased autophagy by activating MAPK14/p38 α both in HR and LR patients. Interestingly, proteins codified in the RD1 region did not interfere with IFNG and IL17A autophagy induction. Therefore, in severe tuberculosis patients' monocytes, IL17A was unable to augment autophagy because of a defect in the MAPK1/3 signaling pathway. In contrast, both IFNG and IL17A increased autophagy levels in patients with strong immunity to Mt, promoting mycobacterial killing. Our findings might contribute to recognize new targets for the development of novel therapeutic tools to fight the pathogen.  相似文献   
109.
The effects of boron (B) deficiency on carbohydrate concentrations and the pattern of phenolic compounds were studied in leaves of tobacco plants (Nicotiana tabacum L.). Plants grown under B deficiency showed a notable increase in leaf carbohydrates and total phenolic compounds when compared to controls. The qualitative composition of phenolics was analyzed by HPLC-mass spectrometry. The level of caffeate conjugates (i.e., chlorogenic acid) increased in B-deficient plants. In addition, the accumulation of two caffeic acid amides (N-caffeoylputrescine and putative dicaffeoylspermidine) was observed.  相似文献   
110.
Human tourists share space with, touch, feed, and otherwise interact with Macaca at multiple locations. Across Asia and stretching to Gibraltar and Northern Africa, macaques form a substantial tourist attraction as their ranges become increasingly coincident with human use zones. Residing in or as tourist attractions, macaques frequently generate economic benefits to local humans and compete with them for habitat and specific resources. In addition, health conflicts may emerge from increased overlap and interactions between humans and macaques. There is only a handful of studies on the impact, structure, context, and cultural ecology of macaque tourist sites. We provide a general overview of 2 macaque tourist sites, one in Padangtegal, Bali, Indonesia and one in Gibraltar. Qualitative assessment reveals variability in behavioral, ecological, economic, and politically relevant facets of macaque tourism. Specifically, differences in aggression during interactions, potential health dangers, economic factors, and local human perceptions between Padangtegal and Gibraltar suggest that qualitative assessments can assist in our construction of broader models and conceptualizations of the interaction context.  相似文献   
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