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31.
A female specimen of the slender sunfish Ranzania laevis of 600 mm total length was recorded for the first time from the Red Sea after being stranded on a shallow sandy bay at Hurghada beach (27° 06′ 16″ N; 33° 50′ 01″ E) on 13 May 2012. Ranzania laevis is believed to have migrated from the Indian Ocean as the nearest area where it was found is coastal waters of Oman.  相似文献   
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Malondialdehyde (MDA) is one of the most commonly reported biomarkers of lipid peroxidation in clinical studies. The reaction of thiobarbituric acid (TBA) with MDA to yield a pink chromogen attributable to an MDA-TBA2 adduct is a common assay approach with products being quantified by ultraviolet-Vis assay as nonspecific TBA-reactive substances (TBARS) or chromatographically as MDA. The specificity of the TBARS assay was compared with both chromatographic assays for total plasma MDA. The levels of total plasma MDA were significantly lower than the plasma TBARS in each of the samples examined, and interestingly, the interindividual variation apparent in the level of plasma MDA was not evident in the plasma TBARS assay. Each of the four online chromatographic detectors yielded a precise, sensitive, and accurate determination of total plasma MDA, and selected-ion monitoring was the most-accurate assay (101.3%, n = 4). The online diode array detectors provided good assay specificity (peak purity index of 999), sensitivity, precision, and accuracy. This research demonstrates the inaccuracy that is inherent in plasma TBARS assays, which claim to quantify MDA, and it is proposed that the TBARS approach may limit the likelihood of detecting true differences in the level of lipid peroxidation in clinical studies.  相似文献   
33.
Gibberellin (GA) plays versatile roles in the regulation of plant growth and development and therefore is widely used as a regulator in agriculture. We performed a chemical library screening and identified a chemical, named 67D, as a stimulator of seed germination that was suppressed by paclobutrazol (PAC), a GA biosynthesis inhibitor. In vitro binding assays indicated that 67D binds to the GID1 receptor. Further studies on the structure–activity relationship identified a chemical, named chemical 6, that strongly promoted seed germination suppressed by PAC. Chemical 6 was further confirmed to promote the degradation of RGA (for repressor of ga1-3), a DELLA protein, and suppress the expression levels of GA3ox1 in the same manner as GA does. 67D and its analogs are supposed to be agonists of GID1 and are expected to be utilized in agriculture and basic research as an alternative to GA.  相似文献   
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Applied Biochemistry and Microbiology - Vit v 1 as a lipid-transfer protein is a major allergen of grapes (Vitis vinifera) that elicits food allergy in many patients in Iran. Todays, recombinant...  相似文献   
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Nucleases play important roles in DNA synthesis, recombination and repair. We have previously shown that human exonuclease 1 (hEXO1) is phosphorylated in response to agents stalling DNA replication and that hEXO1 consequently undergoes ubiquitination and degradation in a proteasome-dependent manner. In the present study, we have addressed the identity of the pathway transducing stalled-replication signals to hEXO1. Using chemical inhibitors, RNA interference, ATM- and ATR-deficient cell lines we have concluded that hEXO1 phosphorylation is ATR-dependent. By means of mass spectrometry, we have identified the sites of phosphorylation in hEXO1 in undamaged cells and in cells treated with hydroxyurea (HU). hEXO1 is phosphorylated at nine basal sites and three additional sites are induced by HU treatment. Analysis of single- and multiple-point mutants revealed that mutation to Ala of the three HU-induced sites of phosphorylation partially rescued HU-dependent degradation of hEXO1 and additionally stabilized the protein in non-treated cells. We have raised an antibody to pS714, an HU-induced site of the S/T-Q type, and we provide evidence that S714 is phosphorylated upon HU but not IR treatment. The antibody may be a useful tool to monitor signal transduction events triggered by stalled DNA replication.  相似文献   
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Present study probes the role of peroxynitrite (ONOO-)-modified thymidine-5′-monophosphate (TMP) in SLE patients with different disease activity scores according to the SLE Disease Activity Index (SLEDAI). Serum analysis showed significant increased number of subjects positive for anti-ONOO--TMP-protein antibodies in SLE patients with different SLEDAI scores. Interestingly, the levels of these antibodies were significantly higher among SLE patients, whose SLEDAI scores were ≥20. In addition, a significant correlation was observed between the levels of anti-ONOO--TMP-protein antibodies and the SLEDAI score (r = 0.595, p < 0.0001). In short, this study shows a positive association between anti-ONOO--TMP-protein antibodies and SLEDAI. The stronger response observed in patients with higher SLEDAI scores suggests that anti-ONOO--TMP-protein antibodies may be useful in evaluating the progression of SLE and in elucidating the mechanisms of disease pathogenesis.  相似文献   
39.
Aiming to identify new sources of bioactive secondary metabolites, we isolated 82 endophytic fungi from stems and barks of the native Brazilian tree Caesalpinia echinata Lam. (Fabaceae). We tested their ethyl acetate extracts in several in vitro assays. The organic extracts from three isolates showed antibacterial activity against Staphylococcus aureus and Escherichia coli [minimal inhibitory concentration (MIC) 32-64 μg/mL]. One isolate inhibited the growth of Salmonella typhimurium (MIC 64 μg/mL) and two isolates inhibited the growth of Klebsiella oxytoca (MIC 64 μg/mL), Candida albicans and Candida tropicalis (MIC 64-128 μg/mL). Fourteen extracts at a concentration of 20 μg/mL showed antitumour activities against human breast cancer and human renal cancer cells, while two isolates showed anti-tumour activities against human melanoma cancer cells. Six extracts were able to reduce the proliferation of human peripheral blood mononuclear cells, indicating some degree of selective toxicity. Four isolates were able to inhibit Leishmania (Leishmania) amazonensis and one isolate inhibited Trypanosoma cruzi by at least 40% at 20 μg/mL. The trypanocidal extract obtained from Fusarium sp. [KF611679] culture was subjected to bioguided fractionation, which revealed beauvericin as the compound responsible for the observed toxicity of Fusarium sp. to T. cruzi. This depsipeptide showed a half maximal inhibitory concentration of 1.9 μg/mL (2.43 μM) in a T. cruzi cellular culture assay.  相似文献   
40.
The aim of the present study was to analyse the usefulness of the 6-20 rating of perceived exertion (RPE) scale for prescribing and self-regulating high-intensity interval training (HIT) in young individuals. Eight healthy young subjects (age = 27.5±6.7 years) performed maximal graded exercise testing to determine their maximal and reserve heart rate (HR). Subjects then performed two HIT sessions (20 min on a treadmill) prescribed and regulated by their HR (HR: 1 min at 50% alternated with 1 min at 85% of reserve HR) or RPE (RPE: 1 minute at the 9-11 level [very light-fairly light] alternated with 1 minute at the 15-17 level [hard-very hard]) in random order. HR response and walking/running speed during the 20 min of exercise were compared between sessions. No significant difference between sessions was observed in HR during low- (HR: 135±15 bpm; RPE: 138±20 bpm) and high-intensity intervals (HR: 168±15 bpm; RPE: 170±18 bpm). Walking/running speed during low- (HR: 5.7±1.2 km · h−1; RPE: 5.7±1.3 km · h−1) and high-intensity intervals (HR: 7.8±1.9 km · h−1; RPE: 8.2±1.7 km · h−1) was also not different between sessions. No significant differences were observed in HR response and walking/running speed between HIT sessions prescribed and regulated by HR or RPE. This finding suggests that the 6-20 RPE scale may be a useful tool for prescribing and self-regulating HIT in young subjects.  相似文献   
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