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1.
A new tortoise beetle species, Cyrtonota abrili, is described from the Antioquia and Caldas departments in Colombia. New faunistic data are provided for 87 species, including 16 new additions to the country’s fauna. A checklist of the known 238 species of tortoise beetles recorded from Colombia is given.  相似文献   
2.
The accurate determination of DNA concentration is essential for many processes in molecular biology and physiology and includes both gel- and cuvette-based methods. The recently introduced fluorescent dye, PicoGreen, has several advantages over other methods because it is sensitive and specific for double-stranded DNA (dsDNA). The dye is excited at 480 nm and emits at 520 nm when bound to dsDNA. This report describes the construction and use of PicoGmeter, a simple, inexpensive, fixed-wavelength fluorometer suitable for measuring PicoGreen fluorescence. PicoGmeter employs a blue light emitting diode (LED) for excitation and a photodiode to measure fluorescence. When compared to a commercially available instrument, PTI DeltaScan, the PicoGmeter performed admirably. Calibration curves for both instruments were superimposeable. Moreover, there was no significant difference between concentrations of DNA estimated by both instruments. A Bland and Altman analysis revealed that the PicoGmeter was equivalent to the PTI DeltaScan for estimating dsDNA concentration by the PicoGreen method. This simple, inexpensive, battery-operated fluorometer will allow investigators to employ the PicoGreen method without incurring the cost of purchasing a spectrofluorometer.  相似文献   
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Damage to cardiac contractile proteins during ischemia followed by reperfusion is mediated by reactive oxygen species such as peroxynitrite (ONOO), resulting in impairment of cardiac systolic function. However, the pathophysiology of systolic dysfunction during ischemia only, before reperfusion, remains unclear. We suggest that increased ONOO generation during ischemia leads to nitration/nitrosylation of myosin light chain 1 (MLC1) and its increased degradation by matrix metalloproteinase-2 (MMP-2), which leads to impairment of cardiomyocyte contractility. We also postulate that inhibition of ONOO action by use of a ONOO scavenger results in improved recovery from ischemic injury. Isolated rat cardiomyocytes were subjected to 15 and 60 min. of simulated ischemia. Intact MLC1 levels, measured by 2D gel electrophoresis and immunoblot, were shown to decrease with increasing duration of ischemia, which correlated with increasing levels of nitrotyrosine and nitrite/nitrate. In vitro degradation of human recombinant MLC1 by MMP-2 increased after ONOO exposure of MLC1 in a concentration-dependent manner. Mass spectrometry analysis of ischemic rat cardiomyocyte MLC1 showed nitration of tyrosines 78 and 190, as well as of corresponding tyrosines 73 and 185 within recombinant human cardiac MLC1 treated with ONOO. Recombinant human cardiac MLC1 was additionally nitrosylated at cysteine 67 and 76 corresponding to cysteine 81 of rat MLC1. Here we show that increased ONOO production during ischemia induces MLC1 nitration/nitrosylation leading to its increased degradation by MMP-2. Inhibition of MLC1 nitration/nitrosylation during ischemia by the ONOO scavenger FeTPPS (5,10,15,20-tetrakis-[4-sulfonatophenyl]-porphyrinato-iron[III]), or inhition of MMP-2 activity with phenanthroline, provides an effective protection of cardiomyocyte contractility.  相似文献   
5.
Enzymes in Bast Fibrous Plant Processing   总被引:7,自引:0,他引:7  
The program COST Action 847 Textile Quality and Biotechnology (2000–2005) has given an excellent chance to review the possibilities of the research, aiming at development of the industrial application of enzymes for bast fibrous plant degumming and primary processing. The recent advancements in enzymatic processing of bast fibrous plants (flax, hemp, jute, ramie and alike plants) and related textiles are given. The performance of enzymes in degumming, modification of bast fibres, roving, yarn, related fabrics as well as enzymatic bonding of lignocellulosic composites is provided.  相似文献   
6.
In this study, we examined the response of glioma C6 cells to 2′,3′-O-(4-benzoylbenzoyl)-ATP (BzATP) and showed that the BzATP-induced calcium signaling does not involve the P2X7 receptor activity. We show here that in the absence of extracellular Ca2+, BzATP-generated increase in [Ca2+]i via Ca2+ release from intracellular stores. In the presence of calcium ions, BzATP established a biphasic Ca2+ response, in a manner typical for P2Y receptors. Brilliant Blue G, a selective antagonist of the rat P2X7 receptor, did not reduce any of the two components of the Ca2+ response elicited by BzATP. Periodate-oxidized ATP blocked not only BzATP- but also UTP-induced Ca2+ elevation. Moreover, BzATP did not open large transmembrane pores. What is more, a cross-desensitization between UTP and BzATP occurred, which clearly shows that in glioma C6 cells BzATP activates most likely the P2Y2 but not the P2X7 receptors.  相似文献   
7.
Staphylokinase is a 135 amino acid protein produced by certain strains of Staphylococcus aureus. It belongs to fibrin-specific plasminogen activator. Staphylokinase converts plasminogen--the inactive proenzyme--to the plasmin, which dissolves the fibrin of a blood clots. This review will focus on the biochemical and thrombolytic properties of staphylokinase and its derivatives, which would make use of treatment in acute myocardial infarction and other cardiovascular diseases.  相似文献   
8.
A series of 5-aryl-4-(5-substituted-2,4-dihydroxyphenyl)-1,2,3-thiadiazoles were synthesized and their binding to several constructs of human Hsp90 chaperone measured by isothermal titration calorimetry (ITC). The most potent compound bound Hsp90 with the dissociation constant of about 5 nM.  相似文献   
9.
Recombinant human erythropoietin (rhEPO) has been used clinically to alleviate cancer- and chemotherapy-related anemia. However, recent clinical trials have reported that rhEPO also may adversely impact disease progression and survival. The expression of functional EPO receptors (EPOR) has been demonstrated in many human cancer cells where, at least in vitro, rhEPO can stimulate cell growth and survival and may induce resistance to selected therapies.  相似文献   
10.
Rat brain proteome in morphine dependence   总被引:4,自引:0,他引:4  
The aim of this study was to reveal potential markers associated with drug dependence, using the proteomic approach. Gels containing samples derived from morphine-treated and control animals were compared and analyzed. Inspection of protein profiles, following TCA/acetone precipitation and the use of nano-scale liquid chromatography coupled to tandem mass spectrometry, allowed for identification of eleven potential dependence markers, mainly cytoplasmic and mitochondrial enzymes, e.g. proteins that belong to GTPase and GST superfamilies, ATPase, asparaginase or proteasome subunit p27 families.  相似文献   
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