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81.
Two new species are described from the tropical forest of Belize: Coptotriche singularis (host-plant unknown) and C. forsteroniae (leaf-miner on Forsteronia myriantha, Apocynaceae). The external features and male genitalia are figured and described for both species. A checklist of Coptotriche species comprising 31 species currently known from the Americas is given. Most of the species are known from mainland USA and Canada, and only a few from the Neotropics (the Caribbean and Belize).  相似文献   
82.
The development of a simple, efficient and cost-effective system for generation of measles virus nucleoprotein might help to upgrade reagents for measles serology. The gene encoding measles nucleoprotein was successfully expressed in two different yeast genera, Pichia pastoris and Saccharomyces cerevisiae, respectively. Both yeast genera synthesized a high level of nucleoprotein, up to 29 and 18% of total cell protein, in P. pastoris and S. cerevisiae, respectively. This protein is one of most abundantly expressed in yeast. After purification nucleocapsid-like particles (NLPs) derived from both yeast genera appeared to be similar to those detected in mammalian cells infected with measles virus. A spontaneous assembly of nucleoprotein into nucleocapsid-like particles in the absence of the viral leader RNA or viral proteins has been shown. Compartmentalisation of recombinant protein into large compact inclusions in the cytoplasm of yeast S. cerevisiae by green fluorescence protein (GFP) fusion has been demonstrated. Sera from measles patients reacted with the recombinant protein expressed in both yeast genera and a simple diagnostic assay to detect measles IgM could be designed on this basis.  相似文献   
83.
Mitochondrial medicine was established more than 50 years ago after discovery of the very first pathology caused by impaired mitochondria. Since then, more than 100 mitochondrial pathologies have been discovered. However, the number may be significantly higher if we interpret the term “mitochondrial medicine” more widely and include in these pathologies not only those determined by the genetic apparatus of the nucleus and mitochondria, but also acquired mitochondrial defects of non-genetic nature. Now the main problems of mitochondriology arise from methodology, this being due to studies of mitochondrial activities under different models and conditions that are far from the functioning of mitochondria in a cell, organ, or organism. Controversial behavior of mitochondria (“friends and foes”) to some extent might be explained by their bacterial origin with possible preservation of “egoistic” features peculiar to bacteria. Apparently, for normal mitochondrial functioning it is essential to maintain homeostasis of a number of mitochondrial elements such as mitochondrial DNA structure, membrane potential, and the system of mitochondrial quality control. Abrogation of these elements can cause a number of pathologies that have become subjects of mitochondrial medicine. Some approaches to therapy of mitochondrial pathologies are discussed.  相似文献   
84.
In this study an on-line electrochemical method was developed to examine the one-step growth cycle (OSGC) of the bacteriophage Bam35. The on-line conditions for monitoring the OSGC and the effect of aeration on the duration of the OSGC were defined. The data indicate that binding of phenyldicarbaundecaborane anions to Bacillus thuringiensis cells infected with Bam35 can be used as a sensitive indicator of cell lysis.  相似文献   
85.
For many decades pharmacological drugs based on lithium salts have been successfully used in psychiatry to treat bipolar disorder, and they remain the “gold standard” of pharmacological therapy of patients with this disease. At the same time, over recent years in experiments in vitro and in vivo a plethora of evidence has accumulated on a positive effect of lithium ions in other areas including their neuro-, cardio-, and nephroprotective properties, regulation of stem cells functions, regulation of inflammation, and others. Numerous studies have shown that the effect of lithium ions involves several mechanisms; however, one of its main targets in the implementation of most of the effects is glycogen synthase kinase 3β, a key enzyme in various pathological and protective signaling pathways in cells. However, one of the main limitations of the use of lithium salts in clinics is their narrow therapeutic window, and the risk of toxic side effects. This review presents the diversity of effects of lithium ions on the organism emphasizing their potential clinical applications with minimal undesirable side effects. In the end, we present a schematic “Lithiometer”, comparing the range of Li+ concentrations that might be used for the treatment of acute pathologies with possible toxic effects of Li+.  相似文献   
86.
β3-Adrenergic receptor (β3-AR) is expressed in human atrial and ventricular tissues. Recently, we have demonstrated that it was involved in the activation of L-type Ca2+ current (I Ca,L) in human atrial myocytes and the force of contraction of human atrial trabeculae. In the present study, we examined the effect of β3-AR agonist CGP12177 which also is a β1-AR/β2-AR antagonist on I Ca,L in human ventricular myocytes (HVMs) and the force of contraction of human ventricular trabeculae. CGP12177 stimulated I Ca,L in HVMs with high potency but much lower efficacy than isoprenaline. The β3-AR antagonist L-748,337 inhibited the effect of CGP12177. CGP12177 and L748,337 competed selectively on β3-ARs because L748,337 had no effect on isoprenaline-induced stimulation of I Ca,L, while CGP12177 completely blocked the effect of isoprenaline. The activation of β3-ARs by CGP12177 does not involve the activation of Gi proteins because CGP12177 had no effect on forskolin-induced stimulation of I Ca,L. CGP12177 had no effect on the force of contraction of human ventricular trabeculae. L-NMMA, an inhibitor of NO synthase, and IBMX, a nonselective inhibitor of phosphodiesterases, did not potentiate the effect of CGP12177 either on contraction of human ventricular trabeculae or on I Ca,L in HVMs. We conclude that in human ventricles β3-AR activation has no inotropic effect, while it slightly increases I Ca,L. In contrast to human atrium, the activation of β3-ARs in human ventricle is not accompanied by increased activity of phosphodiesterases.  相似文献   
87.
Sruoga V  Puplesis R 《Zoological science》2003,20(10):1273-1277
Stephensia armata sp. n., a remarkable species is described from Belize (Central America). The external features and genitalia of the male are figured and described in detail. A distribution map for all six Elachistidae species, currently recorded from tropical America, is given: Perittia smaragdophanes (Meyrick), P. punatensis Kaila, Elachista albisquamella Zeller, E. saccharella (Busck), E. vasrana Kaila and Stephensia armata Sruoga, sp. n.  相似文献   
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