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11.
Two different pre-sowing techniques have been investigated for their influence in an important industrial plant, namely cotton. Priming methods are very useful for agricultural practices because they improve crop seedling establishment, especially when environmental conditions are not optimum. Pulsed electromagnetic fields have been found to promote germination and improve early growth characteristics of cotton seedlings. Such priming techniques are especially valuable in organic cultivation, where chemical compounds are prohibited. PEG treatment showed an enhancement in some measurements, however in some cases the results were not statistically different compared to control plants. In addition, PEG treatment is a sophisticated method that is far from agricultural practices and farmers. In this research, two different ages of seeds were used (1- and 2-year-old) in order to investigate the promotory effects of priming techniques. Magnetic field treatment of 15?min was found to stimulate germination percentage and to promote seeds, resulting in 85% higher values than control seeds under real field conditions. Furthermore, seeds that were treated with magnetic field performed better in terms of early-stage measurements and root characteristics.  相似文献   
12.
Glucuronidation, mediated by the UDP-glucuronosyltransferase 1A1 (UGT1A1) enzyme, is an important metabolic process during which steroids are converted to more easily excreted compounds in steroid target tissues, such as the prostate. The aim of our study was to investigate the possible correlation between UGT1A1 promoter gene polymorphism and benign prostatic hyperplasia. 421 blood samples were obtained from 138 consecutive patients diagnosed with benign prostatic hypeplasia (BPH group) and 283 healthy volunteers (control group). A(TA)6TAA promoter polymorphism of UGT1A1 gene was studied using the Fragment Analysis Software of an automated DNA sequencer and three genotypes (homozygous 7/7, heterozygous 6/7 and normal homozygous 6/6) were identified. No significant differences were observed between the BPH group and controls regarding the genotyping distribution of the three UGT1A1 promoter genotypes (P = 0.39). Also, no association was found between overall disease risk and the presence of the polymorphic homozygous genotype (TA(7)/TA)7) vs. TA(6)/TA(7) + TA(6)/TA(6)) (P = 0.31). Our data suggest that the TA repeat polymorphism of UGT1A1 is not associated with increased BPH risk susceptibility in Caucasian men.  相似文献   
13.
BACKGROUND AND AIMS: Depending on cultivar, surfaces of young leaves of Vitis vinifera may be glabrous-green ('Soultanina') or transiently have anthocyanins ('Siriki') or pubescence ('Athiri'). A test is made of the hypothesis that anthocyanins and pubescence act as light screens affording a photoprotective advantage to the corresponding leaves, and an assessment is made of the magnitude of their effect. METHODS: Measurements were made on young leaves of the three cultivars in spring under field conditions. Photosynthetic gas-exchange and in vivo chlorophyll fluorescence were measured. Photosynthetic and photoprotective pigments were analysed by HPLC. KEY RESULTS: Compared with glabrous-green leaves, both anthocyanic and pubescent leaves had greater dark-adapted PSII photochemical efficiency and net photosynthesis. In leaves possessing either anthocyanins or pubescence, the ratio of xanthophyll cycle components to total chlorophyll, and mid-day de-epoxidation state of the xanthophyll cycle were considerably smaller, than in glabrous-green leaves. These differences were more evident in pubescent leaves, probably indicating that trichomes were more effective in decreasing light stress than anthocyanins in the epidermis. CONCLUSIONS: Light screens, especially in the form of pubescence, decrease the risk of photoinhibition whilst allowing leaves to maintain a smaller content of xanthophyll cycle components and depend less on xanthophyll cycle energy dissipation. This combination of photoprotective features, i.e. decreased photon flux to the photosynthetic apparatus and lower xanthophyll cycle utilization rates may be particularly advantageous under stressful conditions.  相似文献   
14.
 The 1q21 to 25 region of human chromosome 1 contains genes which encode proteins with immune- and inflammation-associated functions. These include the pentraxin genes, for C-reactive protein (CRP), serum amyloid P (SAP) protein (APCS), and a CRP pseudogene (CRPP1). The region of chromosome 1 containing this cluster is syntenic with distal mouse chromosome 1. We constructed an approximately 1.4 megabase yeast artificial chromosome (YAC) contig with the pentraxin genes at its core. This four-YAC contig includes other genes with immune functions including the FCER1A gene, which encodes the α-subunit of the IgE high-affinity Fc receptor and the IFI-16 gene, an interferon-γ-induced gene. In addition, it contains the histone H3F2 and H4F2 genes and the gene for erythroid α-spectrin (SPTA1). The gene order is cen.-SPTA1-H4F2-H3F2-IFI-16-CRP-CRPP1-APCS-FCER1A- tel. The contig thus consists of a cluster of genes whose products either have immunological importance, bind DNA, or both. Received: 13 December 1995 / 6 February 1996  相似文献   
15.
Osteoarthritis (OA) is an age-related degenerative disease comprising the main reason of handicap in the Western world. Interestingly, to date, there are neither available biomarkers for early diagnosis of the disease nor any effective therapy other than symptomatic treatment and joint replacement surgery. OA has long been associated with obesity, mainly due to mechanical overload exerted on the joints. Recent studies however, point to the direction that OA is a metabolic disease, as it also involves non-weight bearing joints. In fact, altered lipid metabolism may be the underlying cause. First, adipokines have been shown to be key regulators of OA pathogenesis. Second, epidemiological studies have shown serum cholesterol to be a risk factor for OA development. Third, lipid deposition in the joint is observed at the early stages of OA before the occurrence of histological changes. Fourth, proteomic analyses have shown an important connection between OA and lipid metabolism. Finally, recent gene expression studies reveal a deregulation of cholesterol influx and efflux and in the expression of lipid metabolism-related genes. Interestingly, lipids and lipid metabolism are known to be implicated in the development and progression of another age-related degenerative disease, atherosclerosis (ATH). Thus, although it is tempting to speculate that the osteoarthritic chondrocyte has been transformed to foam cell, it has not been proven yet. However, this may be an intriguing theory linking ATH and OA, which may open new avenues to novel therapeutic interventions for OA taking advantage of previous knowledge from ATH.  相似文献   
16.
To test the hypothesis that sex determination in the European sea bass (Dicentrarchus labrax L.) Can be affected by the incubating temperature during the very early developmental stages, eggs from the same batch of spontaneously spawned broodstock were divided at the stage of half-epiboly into three groups according to rearing temperature: G13 = 13 degrees C, G15 = 15 degrees C, and G20 = 20 degrees C. Temperature treatment lasted until the middle of metamorphosis (17-18 mm total length, [TL]), and, with the exclusion of water temperature, all biotic and abiotic conditions were identical for the three experimental groups. The on-growing phase was performed under ambient photoperiod and temperature conditions for all groups. Sex proportions were determined by histological examination of the gonads of fish at 308, 467, and 568 days posthatch (DPH). At 308 DPH (TL: 135-201 mm), 100% of the specimens had differentiated into males and females. A significantly higher (P < 0.01) proportion of females was found in groups G13 (72-74%) and G15 (67-73%) than in group G20 (24-28%). At the final sampling there was no statistically significant difference in body weight between the experimental groups. However, in all groups, female fish were larger than males (P < 0.001). Results provide for the first time clear evidence that temperature during the very early developmental stages is the crucial factor affecting the process of sex differentiation of the sea bass, with low rearing temperatures (13 or 15 degrees C) resulting in sex proportions consistently skewed in favor of females.  相似文献   
17.
18.
Cachexia is a multifactorial syndrome characterized by skeletal muscle loss, with or without adipose atrophy, irreversible through nutritional support, in the context of systemic inflammation and metabolic disorders. It is mediated by inflammatory reaction and affects almost 50% of all cancer patients, due to prominent systemic inflammation associated with the disease. The comprehension of the molecular mechanisms that are implicated in cancer cachexia sheds light on its pathogenesis and lays the foundations for the discovery of new therapeutic targets and biomarkers. Recently, ncRNAs, like microRNAs as well as lncRNAs and circRNAs seem to regulate pathways that are implicated in cancer cachexia pathogenesis, as it has been observed in animal models and in cancer cachexia patients, highlighting their therapeutic potential. Moreover, increasing evidence highlights the involvement of circulating and exosomal ncRNAs in the activation and maintenance of systemic inflammation in cancer and cancer-associated cachexia. In that context, the present review focuses on the clinical significance of ncRNAs in cancer-associated cachexia.  相似文献   
19.
The yeast flora associated with healthy and Botrytis-infected grapes was assessed. Molecular identification methods assigned isolates to six genera and nine species. For the first time Hanseniaspora opuntiae was encountered as an inhabitant of the grape ecosystem. By using DraI, an informative restriction fragment length polymorphism pattern was generated to distinguish H. opuntiae from the closely related organism Hanseniaspora guilliermondii. Botrytis infection resulted in a larger population and greater diversity of yeasts enriched with fermentative or spoilage species.  相似文献   
20.

Background

Osteoarthritis is a multifactorial disease characterized by destruction of the articular cartilage due to genetic, mechanical and environmental components affecting more than 100 million individuals all over the world. Despite the high prevalence of the disease, the absence of large-scale molecular studies limits our ability to understand the molecular pathobiology of osteoathritis and identify targets for drug development.

Methodology/Principal Findings

In this study we integrated genetic, bioinformatic and proteomic approaches in order to identify new genes and their collaborative networks involved in osteoarthritis pathogenesis. MicroRNA profiling of patient-derived osteoarthritic cartilage in comparison to normal cartilage, revealed a 16 microRNA osteoarthritis gene signature. Using reverse-phase protein arrays in the same tissues we detected 76 differentially expressed proteins between osteoarthritic and normal chondrocytes. Proteins such as SOX11, FGF23, KLF6, WWOX and GDF15 not implicated previously in the genesis of osteoarthritis were identified. Integration of microRNA and proteomic data with microRNA gene-target prediction algorithms, generated a potential “interactome” network consisting of 11 microRNAs and 58 proteins linked by 414 potential functional associations. Comparison of the molecular and clinical data, revealed specific microRNAs (miR-22, miR-103) and proteins (PPARA, BMP7, IL1B) to be highly correlated with Body Mass Index (BMI). Experimental validation revealed that miR-22 regulated PPARA and BMP7 expression and its inhibition blocked inflammatory and catabolic changes in osteoarthritic chondrocytes.

Conclusions/Significance

Our findings indicate that obesity and inflammation are related to osteoarthritis, a metabolic disease affected by microRNA deregulation. Gene network approaches provide new insights for elucidating the complexity of diseases such as osteoarthritis. The integration of microRNA, proteomic and clinical data provides a detailed picture of how a network state is correlated with disease and furthermore leads to the development of new treatments. This strategy will help to improve the understanding of the pathogenesis of multifactorial diseases such as osteoarthritis and provide possible novel therapeutic targets.  相似文献   
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