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441.
442.
We monitored the productivity of the critically endangered Madagascar Fish Eagle Haliaeetus vociferoides inside and outside of the Tsimembo-Manambolomaty Protected Area (T-M PA), western Madagascar from 2010 to 2015. We recorded 14 breeding pairs inside and 13 outside T-M PA. The T-M PA and surrounding habitat hosted respectively 10 and six breeding polyandrous pairs, composed of one adult female and two adult males. During the six-year study period, 101 eggs were laid in nests in T-M PA of which 60 hatched and 58 young fledged. We recorded 62 eggs laid in nests outside the T-M PA of which 39 hatched and 36 young fledged. Productivity was similar at both sites, inside and outside T-M PA, with 0.84 (58/69) and 0.76 (36/47) fledgling per nesting attempt and 0.69 (58/84) and 0.5 (36/72) fledglings per territorial pair, respectively. Polyandrous pairs have higher productivity compared with normal pairs. Threats to Madagascar Fish Eagles and their habitat were low due to the existence of a community-based resource management system called the Local Management Secured System (GELOSE) inside and outside the T-M PA. This system is based on strengthening local traditional customs and rules, and involving local people in managing their natural resources sustainably along with biodiversity conservation.  相似文献   
443.
The red imported fire ants, Solenopsis invicta (Buren), are generally considered pests. They have also been viewed as beneficial predators feeding on other insect pests of various agroecosystems. This study documents the foraging habits of fire ants in a sweetpotato field in Mississippi. Fire ant foraging trails connecting outside colonies to a sweetpotato field were exposed and foraging ants moving out of the field toward the direction of the colony were collected along with the solid food particles they were carrying. The food material was classified as arthropod or plant in origin. The arthropod particles were identified to orders. Fire ant foragers carried more arthropods than plant material. Coleoptera and Homoptera were the most abundant groups preyed upon. These insect orders contain various economically important pests of sweetpotato. Other major hexapod groups included the orders Hemiptera, Diptera and Collembola. The quantity of foraged material varied over the season. No damage to sweetpotato roots could be attributed to fire ant feeding. Imported fire ant foraging may reduce the number of insect pests in sweetpotato fields.  相似文献   
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445.
Nesfatin-1 and ghrelin are the two recently discovered peptide hormones involved in the control of appetite. Besides its main appetite-control function, ghrelin also has anticonvulsant effects, while nesfatin-1 causes depolarization in the paraventricular nucleus (PVN). The aims of this study, therefore, were to investigate: (i) whether there are differences in the concentrations of nesfatin-1 and ghrelin in saliva and serum samples between eplilepsy patients and normal controls and (ii) whether salivary glands produce nesfatin-1. The study included a total of 73 subjects: 8 patients who were newly diagnosed with primary generalized seizures and had recently started antiepileptic drug therapy; 21 who had primary generalized seizures and were continuing with established antiepileptic drug therapy; 24 who had partial seizures (simple: n = 12 or complex: n = 12) and were continuing with established antiepileptic drug therapy; and 20 controls. Salivary gland tissue samples were analyzed for nesfatin-1 expression by immunochemistry and ELISA. Saliva and serum ghrelin levels were measured by ELISA and RIA, and nesfatin-1 levels by ELISA. Nesfatin-1 immunoreactivity was detected in the striated and interlobular parts of the salivary glands and the ducts. The nesfatin-1 level in the brain was around 12 times higher than in the salivary gland. Before antiepileptic treatment, both saliva and serum nesfatin-1 levels were around 160-fold higher in patients who are newly diagnosed with primary generalized epilepsy (PGE) than in controls; these levels decreased with treatment but remained about 10 times higher than the control values. Saliva and serum nesfatin-1 levels from patients with PGE and partial epilepsies who were continuing antiepileptic drugs were also 10-fold higher than control values. Serum and saliva ghrelin levels were significantly (twofold) lower in epileptic patients before treatment than in controls; they recovered somewhat with treatment but remained below the control values. These results suggest that the low ghrelin and especially the dramatically elevated nesfatin-1 levels might contribute to the pathophyisology of epilepsy. Therefore, serum and saliva ghrelin and especially the remarkably increased nesfatin-1 might be candidate biomarkers for the diagnosis of epilepsy and for monitoring the response to anti-epileptic treatment.  相似文献   
446.
To analyze the suitability of Gateway® vectors for transformation of chloroplasts, we converted a standard plastid transformation vector into a Gateway® destination vector containing the necessary recombination sites attR1 and attR2. Insertion of the green fluorescent protein (GFP) coding sequence with associated T7g10 ribosome binding site into this destination vector created the expression vector for transformation of tobacco chloroplasts with the biolistic method. Correct integration of the transgene into the plastid genome was verified by PCR and the homoplasmic nature of the transformed plants was confirmed by Southern Blot analysis. Expression of the GFP reporter protein was monitored by confocal laser scanning microscopy (CLSM) and quantification by western blot analysis showed a GFP accumulation level of 3 % total soluble protein (TSP). The presented results clearly demonstrate that the Gateway® recombination sites are compatible with all steps of plastid transformation, from generation of transplastomic plants to expression of GFP. This is the first report of a plastid transformation vector made by the Gateway® recombinant cloning technology, which proves the suitability of this system for use in chloroplasts.  相似文献   
447.
We discuss the problem of the evolution of the cellular communication system from the RNA world to progenote to the modern cell. Our method analyses syntactical structure of molecular fossils in the non-coding regions of DNA within the information-processing gene model developed earlier. We concluded that sequence-specific binding is an ancient communication process with its origin in the RNA world. Moreover, we illustrate our viewpoint using four evolution snapshots from the first RNA segments, some 4.1 billion years ago, to the first cell, 3.8 billion years ago.  相似文献   
448.
Glutathione transferase (GST) activity towards racemic as well as the resolved enantiomers of 7 beta,8 alpha-dihydroxy-9 alpha,10 alpha-epoxy-7,8,9,10-tetrahydrobenzo[a] pyrene (anti-BPDE) and 1-chloro-2,4-dinitrobenzene (CDNB) was measured in post-microsomal supernatants (PMS) obtained from eight human skin samples. All preparations showed significant activity towards anti-BPDE and an almost exclusive preference for the more tumourigenic (+)-enantiomer. The specific activity towards (+)-anti-BPDE varied about five-fold between different PMS (range 147-781 pmol/min per mg protein) whereas the variation in specific activities towards CDNB was about two-fold (range 30-71 nmol/min per mg protein). The activities obtained with PMS at saturating concentrations of racemic anti-BPDE were about half of the activity towards the (+)-enantiomer indicating that (-)-anti-BPDE competitively inhibits conjugation of the (+)-form. No correlation was evident between the activities towards (+)-anti-BPDE and CDNB implying that different classes of GST isoenzymes participated in the two different reactions. Immunoblot analysis revealed the presence of Class Alpha and Pi isoenzymes whereas Class Mu isoenzymes seemed to be absent in the human skin samples analyzed. Quantitatively, the Class Pi isoenzyme(s) predominated in all skin samples and the amount of enzyme was about 1-3 micrograms GST Pi/mg PMS protein. The almost exclusive conjugation of (+)-anti-BPDE by PMS and previous results with GST Pi enzymes from human placenta suggested that this type of enzymes catalysed the conjugation reaction. The five-fold variation in specific activity towards (+)-anti-BPDE observed among the different PMS may be explained by individual differences in GST Pi content or by the presence of endogenous modifiers of GST activity towards the diol-epoxide.  相似文献   
449.
Probiotics and Antimicrobial Proteins - The objective of this work was to explore the effect of two encapsulating polysaccharides (sodium alginate and carrageenan) on the viability of probiotic...  相似文献   
450.
Abstract

Glucansucrases (GTFs) catalyzes the synthesis of α-glucans from sucrose and oligosaccharides in the presence of an acceptor sugar by transferring glucosyl units to the acceptor molecule with different linkages. The acceptor reactions can be affected by several parameters and this study aimed to determine the optimal reaction parameters for the production of glucansucrase-based oligosaccharides using sucrose and maltose as the donor and acceptor sugars, respectively via a hybrid technique of Response Surface Method (RSM) and Particle Swarm Optimization (PSO). The experimental design was performed using Central Composite Design and the tested parameters were enzyme concentration, acceptor:donor ratio and the reaction period. The optimization studies showed that enzyme concentration was the most effective parameter for the final oligosaccharides yields. The optimal values of the significant parameters determined for enzyme concentration and acceptor:donor ratio were 3.45?U and 0.62, respectively. Even the response surface plots for input parameters verified the PSO results, an experimental validation study was performed for the reverification. The experimental verification results obtained were also consistent with the PSO results. These findings will help our understanding in the role of different parameters for the production of oligosaccharides in the acceptor reactions of GTFs.  相似文献   
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